Merge bk://linux.bkbits.net/linux-2.5 into cam.ac.uk:/home/aia21/tng

Documentation/filesystems/ntfs.txt

 NTFS Overview
 =============
 
-Legato Systems, Inc. (http://www.legato.com) have sponsored Anton Altaparmakov
-to develop NTFS on Linux since June 2001.
-
-To mount an NTFS volume, use the filesystem type 'ntfs'. The driver
-currently works only in read-only mode, with no fault-tolerance supported.
-
-If you enable the dangerous(!) write support, make sure you can recover
-from a complete loss of data. Also, download the Linux-NTFS project
-distribution from Sourceforge at http://sourceforge.net/projects/linux-ntfs/
-and always run the included ntfsfix utility after performing a write to an
-NTFS partition from Linux to fix some of the damage done by the Linux NTFS
-driver and to schedule an automatic chkdsk when Windows reboots. You should
-run ntfsfix _after_ unmounting the partition in Linux but _before_ rebooting
-into Windows. During the next reboot into Windows, chkdsk will be run
-automatically fixing the remaining damage. If no errors are found it is a
-good indication that the driver + ntfsfix together worked to full
-satisfaction. (-;
-
-Please note that the experimental write support is limited to Windows NT4 and
-earlier versions at the moment.
-
-If you think you have discovered a bug please have look at the "Known bugs"
-section below to see whether it isn't known already.
+To mount an NTFS 1.2/3.x (Windows NT4/2000/XP) volume, use the filesystem
+type 'ntfs'. The driver currently works only in read-only mode, with no
+fault-tolerance supported.
 
 For ftdisk support, limited success was reported with volume sets on top of
 the md driver, although mirror and stripe sets should work as well - if the
@@ -34,35 +14,85 @@ number of sectors.
 Supported mount options
 =======================
 
-iocharset=name		Character set to use when returning file names.
+nls=name		Character set to use when returning file names.
 			Unlike VFAT, NTFS suppresses names that contain
 			unconvertible characters. Note that most character
 			sets contain insufficient characters to represent all
 			possible Unicode characters that can exist on NTFS. To
 			be sure you are not missing any files, you are advised
-			to use the iocharset=utf8 which should be capable of
-			representing all Unicode characters.
-
-utf8=<bool>		Use UTF-8 for converting file names. - It is preferable
-			to use iocharset=utf8 instead, but if the utf8 NLS is
-			not available, you can use this utf8 option, which
-			enables the driver's builtin utf8 conversion functions.
+			to use nls=utf8 which is capable of representing all
+			Unicode characters.
 
 uid=
 gid=
-umask=			These options work as documented in mount(8).
-			By default, the files are owned by root and
-			not readable by anyone else.
-
-posix=<bool>		If enabled, the file system distinguishes between
-			upper and lower case. The 8.3 alias names are presented
-			as hard links instead of being suppressed.
-
-show_sys_files=<bool>	If enabled, show all system files as normal files. Note
-			that $MFT does not appear unless specifically
-			requested. For example in bash, use: "ls -l \$MFT".
-			Be careful not to write anything to them or you could
-			crash the kernel and/or corrupt your file system!
+umask=			Provide default owner, group, and access mode mask.
+			These options work as documented in mount(8). By
+			default, the files are owned by root and are not
+			readable by anyone else.
+
+fmask=
+dmask=			Instead of specifying umask which applies both to
+			files and directories, fmask applies only to files and
+			dmask only to directories.
+
+sloppy=<BOOL>		If sloppy is specified, ignore unknown mount options.
+			Otherwise the default behaviour is to abort mount if
+			any unknown options are found.
+
+errors=opt		What to do when critical file system errors are found.
+			Following values can be used for "opt":
+			  continue: DEFAULT, try to clean-up as much as
+				    possible, e.g. marking a corrupt inode as
+				    bad so it is no longer accessed, and then
+				    continue.
+			  recover:  At present only supported is recovery of
+				    the boot sector from the backup copy. If a
+				    read-only mount, the recovery is done in
+				    memory only and not written to disk.
+			Note that the options are additive, i.e. specifying:
+			   errors=continue,errors=recover
+			This means the driver will attempt to recover and if
+			that fails it will clean-up as much as possible and
+			continue.
+
+show_inodes=opt		Allows choice of which types of inode names readdir()
+			returns, i.e. this affects what "ls" shows. Following
+			values can be used for "opt":
+			   system: show system files
+			   win32:  long file names (includes POSIX) [DEFAULT]
+			   long:   same as win32
+			   dos:    short file names only (excludes POSIX)
+			   short:  same as dos
+			   posix:  same as both win32 and dos
+			   all:    all file names
+			Note that the options are additive, i.e. specifying:
+			   show_inodes=system,show_inodes=win32,show_inodes=dos
+			is the same as specifying:
+			   show_inodes=all
+			Note that the "posix" and "all" options will show all
+			directory names, BUT the link count on each directory
+			inode entry is set to 1, due to Linux not supporting
+			directory hard links. This may well confuse some
+			userspace applications, since the directory names will
+			have the same inode numbers. Thus it is NOT advisable
+			to use the "posix" and "all" options. We provide them
+			only for completeness sake.
+			Further, note that the "system" option will not show
+			"$MFT" due to bugs/mis-features in glibc. Even though
+			it does not show, you can specifically "ls" it:
+				ls -l \$MFT
+			And of course you can stat it, too.
+			Further, note that irrespective of what show_inodes
+			option(s) you use, all files are accessible when you
+			specify the correct name, even though they may not be
+			shown in a normal "ls", i.e. you can always access the
+			system files and both the short and long file names of
+			files and directories.
+			Finally, note that win32 and dos file names are not
+			case sensitive and can be accessed using any
+			combination of lower and upper case, while POSIX file
+			names are case sensitive and they can only be accessed
+			given the correct case.
 
 mft_zone_multiplier=	Set the MFT zone multiplier for the volume (this
 			setting is not persistent across mounts and can be
@@ -82,173 +112,27 @@ mft_zone_multiplier=	Set the MFT zone multiplier for the volume (this
 				2		25%
 				3		37.5%
 				4		50%
+			Note this option is irrelevant for read-only mounts.
+
+Features
+========
+
+- Implementation of NTFS read support functionally equivalent to the old ntfs
+  driver.
 
 Known bugs and (mis-)features
 =============================
 
-- Do not use the driver for writing as it corrupts the file system. If you do
-  use it, get the Linux-NTFS tools and use the ntfsfix utility after
-  dismounting a partition you wrote to.
-
-- Writing of extension records is not supported properly.
+- None
 
-Please send bug reports/comments/feed back/abuse to the Linux-NTFS development
+Please send bug reports/comments/feedback/abuse to the Linux-NTFS development
 list at sourceforge: linux-ntfs-dev@lists.sourceforge.net
 
 ChangeLog
 =========
 
-NTFS 1.1.21:
-	- Fixed bug with reading $MFT where we try to read higher mft records
-	  before having read the $DATA attribute of $MFT. (Note this is only a
-	  partial solution which will only work in the case that the attribute
-	  list is resident or non-resident but $DATA is in the first 1024
-	  bytes. But this should be enough in the majority of cases. I am not
-	  going to bother fixing the general case until someone finds this to
-	  be a problem for them, which I doubt very much will ever happen...)
-	- Fixed bogus BUG() call in readdir().
-
-NTFS 1.1.20:
-	- Fixed two bugs in ntfs_readwrite_attr(). Thanks to Jan Kara for
-	  spotting the out of bounds one.
-	- Check return value of set_blocksize() in ntfs_read_super() and make
-	  use of get_hardsect_size() to determine the minimum block size.
-	- Fix return values of ntfs_vcn_to_lcn(). This should stop
-	  peoples start of partition being overwritten at random.
-
-NTFS 1.1.19:
-	- Fixed ntfs_getdir_unsorted(), ntfs_readdir() and ntfs_printcb() to
-	  cope with arbitrary cluster sizes. Very important for Win2k+. Also,
-	  make them detect directories which are too large and truncate the
-	  enumeration pretending end of directory was reached. Detect more
-	  error conditions and overflows. All this fixes the problem where the
-	  driver could end up in an infinite loop under certain circumstances.
-	- Fixed potential memory leaks in Unicode conversion functions and
-	  setup correct NULL return values.
-
-NTFS 1.1.18:
-
-	- Enhanced & bug fixed cluster deallocation (race fixes, etc.)
-	- Complete rewrite of cluster allocation, now race free.
-	- Fixed several bugs in the attribute modification codepaths.
-	- Hopefully fixed bug where the first sectors of some people's
-	  partitions would be overwritten by the mft. And in general fixed up
-	  mft extension code a bit (still incomplete though).
-	- Introduce splice_runlist() to allow generic splicing of two run
-	  lists into one.
-	- MFT zone is now implemented. [Stage 2 of 3; only lack dynamic
-	  growing of mft zone but that is AFAIK not even done by Windows, and
-	  the overhead would be so large that it is probably not worth doing
-	  at all, so Stage 3 might never happen...]
-	- Complete rewrite of $MFT extension and ntfs inode allocation code.
-	- Made the NTFS driver initialization string show the compile options
-	  used (i.e. whether read-only or read-write, whether a module, and
-	  whether with debug support).
-	- Modify ntfs_fill_mft_header() to set all fields and to accept more
-	  arguments.
-	- Get rid of superfluous add_mft_header().
-	- Get rid of some unused code.
-	- Fixed several bugs in and generally cleaned up ntfs_readdir,
-	  ntfs_getdir_unsorted(), and ntfs_printcb. Now they spew out huge
-	  amounts of debug output if debugging is enabled. This will be
-	  removed once I know that this works for everyone.
-	- ntfs_readdir now shows hidden files. The only files that are now
-	  hidden are the first 16 inodes (i.e. the hard coded system files),
-	  which is consistent with Windows NT4. Using the show_sys_files mount
-	  option, these files are then shown, too.
-	- Fixed the displaying of the "." and ".." directories. We still cannot
-	  cope with more than 65536 files in a directory index block which is
-	  not a problem and we now cannot cope with more than 32766 directory
-	  index blocks which should not be a problem unless you have a
-	  directory with an insanely large number of files in it. The exact
-	  number depends on the length of the file names of the directory
-	  entries and on the size of the dircetory index blocks.
-	- Fixed all problems with the last file in a directory (e.g. the last
-	  file should no longer disappear and tab completion should work). If
-	  there are still disappearing files or any other problems with the
-	  last file in a directory, please report them! Thanks.
-	- Rewrote ntfs_extend_attr() to use the new cluster allocator and the
-	  freshly introduced splice_runlists() function. This simplified
-	  ntfs_extend_attr() a lot which in turn seems to have removed one or
-	  more bugs from it.
-	- Probably other things I have forgotten... (-;
-	- Removed dollar signs from the names in the system file enumeration.
-	  Apparently gcc doesn't support dollar signs on PPC architecture.
-	  (Andrzej Krzysztofowicz)
-
-NTFS 1.1.17:
-
-	- Fixed system file handling. No longer need to use show_sys_files
-	  option for driver to work fine. System files are now always treated
-	  the same, but without the option, they are made invisible to
-	  directory listings. As a result system files can once again be opened
-	  even without the show_sys_files option. This is important for the
-	  statfs system call to work properly, for example.
-	- Implemented MFT zone including mount parameter to tune it (just like
-	  in Windows via the registry, only we make it per mount rather than
-	  global for the whole driver, so we are better but we have no way of
-	  storing the value as we don't have a registry so either specify on
-	  each mount or put it in /etc/fstab). [Stage 1 of 3, mount parameter
-	  handling.]
-	- Fixed fixup functions to handle corruption cases and to return error
-	  codes to the caller.
-	- Made fixup functions apply hotfixes where sensible. [Stage 1 of 2+,
-	  in memory only.]
-	- Fixed ommission of "NTFS: " string in ntfs_error() output.
-	- Fixed stupid if statement bug in unistr.c. Thanks to Yann E. Morin
-	  for spotting it. 
-	- Get rid of all uses of max and min macros. This actually allowed for
-	  optimizing the code in several places so it was a Good Thing(TM).
-	- Make ntfs use generic_file_open to enforce the O_LARGEFILE flag.
-	- Detect encrypted files and refuse to access them (return EACCES
-	  error code to user space).
-	- Fix handling of encrypted & compressed files so that an encrypted
-	  file no longer is considered to be compressed (this was causing
-	  kernel segmentation faults).
-
-NTFS 1.1.16:
-
-	- Removed non-functional uni_xlate mount options.
-	- Clarified the semantics of the utf8 and iocharset mount options.
-	- Threw out the non-functional mount options for using hard coded
-	  character set conversion. Only kept utf8 one.
-	- Fixed handling of mount options and proper handling of faulty mount
-	  options on remount.
-	- Cleaned up character conversion which basically became simplified a
-	  lot due to the removal of the above mentioned mount options.
-	- Made character conversion to be always consistent. Previously we
-	  could output to the VFS file names which we would then not accept
-	  back from the VFS so in effect we were generating ghost entries in
-	  the directory listings which could not be accessed by any means.
-	- Simplified time conversion functions drastically without sacrificing
-	  accuracy. (-8
-	- Fixed a use of a pointer before the check for the pointer being
-	  NULL, reported by the Stanford checker.
-	- Fixed several missing error checks, reported by the Stanford
-	  checker and fixed by Rasmus Andersen.
-
-NTFS 1.1.15 (changes since kernel 2.4.4's NTFS driver):
-
-	- New mount option show_sys_files=<bool> to show all system files as
-	  normal files.
-	- Support for files and in general any attributes up to the full 2TiB
-	  size supported by the NTFS filesystem. Note we only support up to
-	  32-bits worth of inodes/clusters at this point.
-	- Support for more than 128kiB sized runlists (using vmalloc_32()
-	  instead of kmalloc()).
-	- Fixed races in allocation of clusters and mft records.
-	- Fixed major bugs in attribute handling / searching / collation.
-	- Fixed major bugs in compressing a run list into a mapping pairs array.
-	- Fixed major bugs in inode allocation. Especially file create and
-	  mkdir.
-	- Fixed memory leaks.
-	- Fixed major bug in inode layout assignment of sequence numbers.
-	- Lots of other bug fixes I can't think of right now...
-	- Fixed NULL bug found by the Stanford checker in ntfs_dupuni2map().
-	- Convert large stack variable to dynamically allocated one in
-	  ntfs_get_free_cluster_count() (found by Stanford checker).
-
-Kernel 2.4.4:
+Note that a technical ChangeLog aimed at kernel hackers is in fs/ntfs/ChangeLog.
 
+TNG-0.0.8:
 	- Started ChangeLog.
 

fs/Config.help

@@ -581,33 +581,36 @@ CONFIG_HPFS_FS
   say N.
 
 CONFIG_NTFS_FS
-  NTFS is the file system of Microsoft Windows NT. Say Y if you want
-  to get read access to files on NTFS partitions of your hard drive.
-  The Linux NTFS driver supports most of the mount options of the VFAT
-  driver, see <file:Documentation/filesystems/ntfs.txt>. Saying Y here
-  will give you read-only access to NTFS partitions.
+  NTFS is the file system of Microsoft Windows NT/2000/XP. For more
+  information see <file:Documentation/filesystems/ntfs.txt>. Saying Y
+  here would allow you to read from NTFS partitions.
 
-  This code is also available as a module ( = code which can be
+  This file system is also available as a module ( = code which can be
   inserted in and removed from the running kernel whenever you want).
   The module will be called ntfs.o. If you want to compile it as a
   module, say M here and read <file:Documentation/modules.txt>.
 
-CONFIG_NTFS_RW
-  If you say Y here, you will (maybe) be able to write to NTFS file
-  systems as well as read from them. The read-write support in NTFS
-  is far from being complete and is not well tested. If you say Y
-  here, back up your NTFS volume first, since it will probably get
-  damaged. Also, download the Linux-NTFS project distribution from
-  Sourceforge at <http://linux-ntfs.sf.net/> and always run the
-  included ntfsfix utility after writing to an NTFS partition from
-  Linux to fix some of the damage done by the driver. You should run
-  ntfsfix _after_ unmounting the partition in Linux but _before_
-  rebooting into Windows. When Windows next boots, chkdsk will be
-  run automatically to fix the remaining damage.
-  Please note that write support is limited to Windows NT4 and
-  earlier versions.
-
-  If unsure, say N.
+  If you are not using Windows NT/2000/XP in addition to Linux on your
+  computer it is safe to say N.
+
+CONFIG_NTFS_DEBUG
+  If you are experiencing any problems with the NTFS file system, say
+  Y here. This will result in additional consistency checks to be
+  performed by the driver as well as additional debugging messages to
+  be written to the system log. Note that debugging messages are
+  disabled by default. To enable them, supply the option debug_msgs=1
+  at the kernel command line when booting the kernel or as an option
+  to insmod when loading the ntfs module. Once the driver is active,
+  you can enable debugging messages by doing (as root):
+    echo 1 > /proc/sys/fs/ntfs-debug
+  Replacing the "1" with "0" would disable debug messages.
+
+  If you leave debugging messages disabled, this results in little
+  overhead, but enabling debug messages results in very significant
+  slowdown of the system.
+
+  When reporting bugs, please try to have available a full dump of
+  debugging messages while the misbehaviour was occurring.
 
 CONFIG_SYSV_FS
   SCO, Xenix and Coherent are commercial Unix systems for Intel

fs/Config.in

@@ -62,8 +62,9 @@ dep_mbool '  JFS statistics' CONFIG_JFS_STATISTICS $CONFIG_JFS_FS
 tristate 'Minix fs support' CONFIG_MINIX_FS
 
 tristate 'FreeVxFS file system support (VERITAS VxFS(TM) compatible)' CONFIG_VXFS_FS
+
 tristate 'NTFS file system support (read only)' CONFIG_NTFS_FS
-dep_mbool '  NTFS write support (DANGEROUS)' CONFIG_NTFS_RW $CONFIG_NTFS_FS $CONFIG_EXPERIMENTAL
+dep_mbool '  NTFS debugging support' CONFIG_NTFS_DEBUG $CONFIG_NTFS_FS
 
 tristate 'OS/2 HPFS file system support' CONFIG_HPFS_FS
 

fs/ntfs/ChangeLog

+ToDo:
+	- Audit for allocated_size vs initialized_size vs data_size (i.e.
+	  i_size) in whole driver.
+	  Need to enforce limits and zeroes need to be written when overflow is
+	  detected. We CANNOT use block_read_full_page() at all anywhere! This
+	  is because initialized_size can lie within a block and ntfs_get_block
+	  has no way to tell block_read_full_page about it. So our readpage
+	  functions need to clone block_read_full_page and modify it to cope
+	  with the significance of the different attribute sizes.
+	  Still need to go through:
+		aops.c, attrib.c, compress.c, dir.c, mft.c
+	- Find and fix bugs.
+	- W.r.t. s_maxbytes still need to be careful on reading/truncating as
+	  there are dragons lurking in the details, e.g. read_inode() currently
+	  does no checks for file size wrt s_maxbytes. So what happens when a
+	  user open()s a file with i_size > s_maxbytes? Should read_inode()
+	  truncate the visible i_size? Will the user just get -E2BIG (or
+	  whatever) on open()? Or will (s)he be able to open() but lseek() and
+	  read() will fail when s_maxbytes is reached? -> Investigate this!
+	- Perhaps don't bother getting the run list in ntfs_read_inode() at
+	  all. But we do have to find the data/index root attribute to get the
+	  inode size so we might want to decompress the mapping pairs of the
+	  first extent in there anyway. -> Ponder this. Directory listings
+	  would have significant speedups but the first access to each file/dir
+	  would have a small speed penalty.
+	- Implement/allow non-resident index bitmaps in ntfs_readdir().
+	- vcn_to_lcn() should somehow return the correct pointer within the
+	  ->run_list so we can get at the lcns for the following vcns, this is
+	  strictly a speed optimization. Obviously need to keep the ->run_list
+	  locked or RACE. load_attribute_list() which we call without any locks
+	  held already performs such an optimization but that is no longer
+	  possible when using the spinlock on the run lists as this would sleep
+	  in between. Either need different type of optimization as above or
+	  need to change the read/write spinlock to a read/write semaphore.
+
+tng-0.0.9 - Work in progress
+
+	- Add kill_super, just keeping up with the vfs changes in the kernel.
+
+tng-0.0.8 - 08/03/2002 - BitKeeper ChangeSet 1.386
+
+	- Replace bdevname(sb->s_dev) with sb->s_id.
+	- Remove now superfluous new-line characters in all callers of
+	  ntfs_debug().
+	- Apply kludge in ntfs_read_inode(), setting i_nlink to 1 for
+	  directories. Without this the "find" utility gets very upset which is
+	  fair enough as Linux/Unix do not support directory hard links.
+	- Further run list merging work. (Richard Russon)
+	- Backwards compatibility for gcc-2.95. (Richard Russon)
+	- Update to kernel 2.5.5-pre1 and rediff the now tiny patch.
+	- Convert to new file system declaration using ->ntfs_get_sb() and
+	  replacing ntfs_read_super() with ntfs_fill_super().
+	- Set s_maxbytes to MAX_LFS_FILESIZE to avoid page cache page index
+	  overflow on 32-bit architectures.
+	- Cleanup upcase loading code to use ntfs_(un)map_page().
+	- Disable/reenable preemtion in critical sections of compession engine.
+	- Replace device size determination in ntfs_fill_super() with
+	  sb->s_bdev->bd_inode->i_size (in bytes) and remove now superfluous
+	  function super.c::get_nr_blocks().
+	- Implement a mount time option (show_inodes) allowing choice of which
+	  types of inode names readdir() returns and modify ntfs_filldir()
+	  accordingly. There are several parameters to show_inodes:
+		system:	system files
+	  	win32:	long file names (including POSIX file names) [DEFAULT]
+		long:	same as win32
+	  	dos:	short file names only (excluding POSIX file names)
+		short:	same as dos
+		posix:	same as both win32 and dos
+	  	all:	all file names
+	  Note that the options are additive, i.e. specifying:
+		-o show_inodes=system,show_inodes=win32,show_inodes=dos
+	  is the same as specifying:
+		-o show_inodes=all
+	  Note that the "posix" and "all" options will show all directory
+	  names, BUT the link count on each directory inode entry is set to 1,
+	  due to Linux not supporting directory hard links. This may well
+	  confuse some userspace applications, since the directory names will
+	  have the same inode numbers. Thus it is NOT advisable to use the
+	  "posix" or "all" options. We provide them only for completeness sake.
+	- Add copies of allocated_size, initialized_size, and compressed_size to
+	  the ntfs inode structure and set them up in
+	  inode.c::ntfs_read_inode(). These reflect the unnamed data attribute
+	  for files and the index allocation attribute for directories.
+	- Add copies of allocated_size and initialized_size to ntfs inode for
+	  $BITMAP attribute of large directories and set them up in
+	  inode.c::ntfs_read_inode().
+	- Add copies of allocated_size and initialized_size to ntfs volume for
+	  $BITMAP attribute of $MFT and set them up in
+	  super.c::load_system_files().
+	- Parse deprecated ntfs driver options (iocharset, show_sys_files,
+	  posix, and utf8) and tell user what the new options to use are. Note
+	  we still do support them but they will be removed with kernel 2.7.x.
+	- Change all occurences of integer long long printf formatting to hex
+	  as printk() will not support long long integer format if/when the
+	  div64 patch goes into the kernel.
+	- Make slab caches have stable names and change the names to what they
+	  were intended to be. These changes are required/made possible by the
+	  new slab cache name handling which removes the length limitation by
+	  requiring the caller of kmem_cache_create() to supply a stable name
+	  which is then referenced but not copied.
+	- Rename run_list structure to run_list_element and create a new
+	  run_list structure containing a pointer to a run_list_element
+	  structure and a read/write spinlock. Adapt all usesrs of run lists
+	  to new scheme and take and release the lock as needed. This fixes a
+	  nasty race as the run_list changes even when inodes are locked for
+	  reading and even when the inode isn't locked at all, so we really
+	  needed the serialization.
+	- Cleanup read_inode() removing all code checking for lowest_vcn != 0.
+	  This can never happen due to the nature of lookup_attr() and how we
+	  support attribute lists. If it did happen it would imply the inode
+	  being corrupt.
+	- Check for lowest_vcn != 0 in ntfs_read_inode() and mark the inode as
+	  bad if found.
+	- Update to 2.5.6-pre2 changes in struct address_space.
+	- Import Sourceforge CVS repository into BitKeeper repository:
+		http://linux-ntfs.bkbits.net/ntfs-tng-2.5
+	- Update fs/Makefile, fs/Config.help, fs/Config.in, and
+	  Documentation/filesystems/ntfs.txt for NTFS TNG.
+	- Create kernel configuration option controlling whether debugging
+	  is enabled or not.
+	- Add the required export of end_buffer_io_sync() from the patches
+	  directory to the kernel code.
+	- Update inode.c::ntfs_show_options() with show_inodes mount option.
+	- Update errors mount option.
+
+tng-0.0.7 - 13/02/2002 - The driver is now feature complete for read-only!
+
+	- Cleanup mft.c and it's debug/error output in particular. Fix a minor
+	  bug in mapping of extent inodes. Update all the comments to fit all
+	  the recent code changes.
+	- Modify vcn_to_lcn() to cope with entirely unmapped run lists.
+	- Cleanups in compress.c, mostly comments and folding help.
+	- Implement attrib.c::map_run_list() as a generic helper.
+	- Make compress.c::ntfs_file_read_compressed_block() use map_run_list()
+	  thus making code shorter and enabling attribute list support.
+	- Cleanup incorrect use of [su]64 with %L printf format specifier in
+	  all source files. Type casts to [unsigned] long long added to correct
+	  the mismatches (important for architectures which have long long not
+	  being 64 bits).
+	- Merge async io completion handlers for directory indexes and $MFT
+	  data into one by setting the index_block_size{_bits} of the ntfs
+	  inode for $MFT to the mft_record_size{_bits} of the ntfs_volume.
+	- Cleanup aops.c, update comments.
+	- Make ntfs_file_get_block() use map_run_list() so all files now
+	  support attribute lists.
+	- Make ntfs_dir_readpage() almost verbatim copy of
+	  block_read_full_page() by using ntfs_file_get_block() with only real
+	  difference being the use of our own async io completion handler
+	  rather than the default one, thus reducing the amount of code and
+	  automatically enabling attribute list support for directory indices.
+	- Fix bug in load_attribute_list() - forgot to call brelse in error
+	  code path.
+	- Change parameters to find_attr() and lookup_attr(). We no longer
+	  pass in the upcase table and its length. These can be gotten from
+	  ctx->ntfs_ino->vol->upcase{_len}. Update all callers.
+	- Cleanups in attrib.c. 
+	- Implement merging of run lists, attrib.c::merge_run_lists() and its
+	  helpers. (Richard Russon)
+	- Attribute lists part 2, attribute extents and multi part run lists:
+	  enable proper support for LCN_RL_NOT_MAPPED and automatic mapping of
+	  further run list parts via attrib.c::map_run_list().
+	- Tiny endianness bug fix in decompress_mapping_pairs().
+
+tng-0.0.6 - Encrypted directories, bug fixes, cleanups, debugging enhancements.
+
+	- Enable encrypted directories. (Their index root is marked encrypted
+	  to indicate that new files in that directory should be created
+	  encrypted.)
+	- Fix bug in NInoBmpNonResident() macro. (Cut and paste error.)
+	- Enable $Extend system directory. Most (if not all) extended system
+	  files do not have unnamed data attributes so ntfs_read_inode() had to
+	  special case them but that is ok, as the special casing recovery
+	  happens inside an error code path so there is zero slow down in the
+	  normal fast path. The special casing is done by introducing a new
+	  function inode.c::ntfs_is_extended_system_file() which checks if any
+	  of the hard links in the inode point to $Extend as being their parent
+	  directory and if they do we assume this is an extended system file.
+	- Create a sysctl/proc interface to allow {dis,en}abling of debug output
+	  when compiled with -DDEBUG. Default is debug messages to be disabled.
+	  To enable them, one writes a non-zero value to /proc/sys/fs/ntfs-debug
+	  (if /proc is enabled) or uses sysctl(2) to effect the same (if sysctl
+	  interface is enabled). Inspired by old ntfs driver.
+	- Add debug_msgs insmod/kernel boot parameter to set whether debug
+	  messages are {dis,en}abled. This is useful to enable debug messages
+	  during ntfs initialization and is the only way to activate debugging
+	  when the sysctl interface is not enabled.
+	- Cleanup debug output in various places.
+	- Remove all dollar signs ($) from the source (except comments) to
+	  enable compilation on architectures whose gcc compiler does not
+	  support dollar signs in the names of variables/constants. Attribute
+	  types now start with AT_ instead of $ and $I30 is now just I30.
+	- Cleanup ntfs_lookup() and add consistency check of sequence numbers.
+	- Load complete run list for $MFT/$BITMAP during mount and cleanup
+	  access functions. This means we now cope with $MFT/$BITMAP being
+	  spread accross several mft records.
+	- Disable modification of mft_zone_multiplier on remount. We can always
+	  reenable this later on if we really want to, but we will need to make
+	  sure we readjust the mft_zone size / layout accordingly.
+
+tng-0.0.5 - Modernize for 2.5.x and further in line-ing with Al Viro's comments.
+
+	- Use sb_set_blocksize() instead of set_blocksize() and verify the
+	  return value.
+	- Use sb_bread() instead of bread() throughout.
+	- Add index_vcn_size{_bits} to ntfs_inode structure to store the size
+	  of a directory index block vcn. Apply resulting simplifications in
+	  dir.c everywhere.
+	- Fix a small bug somewhere (but forgot what it was).
+	- Change ntfs_{debug,error,warning} to enable gcc to do type checking
+	  on the printf-format parameter list and fix bugs reported by gcc
+	  as a result. (Richard Russon)
+	- Move inode allocation strategy to Al's new stuff but maintain the
+	  divorce of ntfs_inode from struct inode. To achieve this we have two
+	  separate slab caches, one for big ntfs inodes containing a struct
+	  inode and pure ntfs inodes and at the same time fix some faulty
+	  error code paths in ntfs_read_inode().
+	- Show mount options in proc (inode.c::ntfs_show_options()).
+
+tng-0.0.4 - Big changes, getting in line with Al Viro's comments.
+
+	- Modified (un)map_mft_record functions to be common for read and write
+	  case. To specify which is which, added extra parameter at front of
+	  parameter list. Pass either READ or WRITE to this, each has the
+	  obvious meaning.
+	- General cleanups to allow for easier folding in vi.
+	- attrib.c::decompress_mapping_pairs() now accepts the old run list
+	  argument, and invokes attrib.c::merge_run_lists() to merge the old
+	  and the new run lists.
+	- Removed attrib.c::find_first_attr().
+	- Implemented loading of attribute list and complete run list for $MFT.
+	  This means we now cope with $MFT being spread across several mft
+	  records.
+	- Adapt to 2.5.2-pre9 and the changed create_empty_buffers() syntax.
+	- Adapt major/minor/kdev_t/[bk]devname stuff to new 2.5.x kernels.
+	- Make ntfs_volume be allocated via kmalloc() instead of using a slab
+	  cache. There are too little ntfs_volume structures at any one time
+	  to justify a private slab cache.
+	- Fix bogus kmap() use in async io completion. Now use kmap_atomic().
+	  Use KM_BIO_IRQ on advice from IRC/kernel...
+	- Use ntfs_map_page() in map_mft_record() and create ->readpage method
+	  for reading $MFT (ntfs_mft_readpage). In the process create dedicated
+	  address space operations (ntfs_mft_aops) for $MFT inode mapping. Also
+	  removed the now superfluous exports from the kernel core patch.
+	- Fix a bug where kfree() was used insted of ntfs_free().
+	- Change map_mft_record() to take ntfs_inode as argument instead of
+	  vfs inode. Dito for unmap_mft_record(). Adapt all callers.
+	- Add pointer to ntfs_volume to ntfs_inode.
+	- Add mft record number and sequence number to ntfs_inode. Stop using
+	  i_ino and i_generation for in-driver purposes.
+	- Implement attrib.c::merge_run_lists(). (Richard Russon)
+	- Remove use of proper inodes by extent inodes. Move i_ino and
+	  i_generation to ntfs_inode to do this. Apply simplifications that
+	  result and remove iget_no_wait(), etc.
+	- Pass ntfs_inode everywhere in the driver (used to be struct inode).
+	- Add reference counting in ntfs_inode for the ntfs inode itself and
+	  for the mapped mft record.
+	- Extend mft record mapping so we can (un)map extent mft records (new
+	  functions (un)map_extent_mft_record), and so mappings are reference
+	  counted and don't have to happen twice if already mapped - just ref
+	  count increases.
+	- Add -o iocharset as alias to -o nls for backwards compatibility.
+	- The latest core patch is now tiny. In fact just a single additional
+	  export is necessary over the base kernel.
+
+tng-0.0.3 - Cleanups, enhancements, bug fixes.
+
+	- Work on attrib.c::decompress_mapping_pairs() to detect base extents
+	  and setup the run list appropriately using knowledge provided by the
+	  sizes in the base attribute record.
+	- Balance the get_/put_attr_search_ctx() calls so we don't leak memory
+	  any more.
+	- Introduce ntfs_malloc_nofs() and ntfs_free() to allocate/free a single
+	  page or use vmalloc depending on the amount of memory requested.
+	- Cleanup error output. The __FUNCTION__ "(): " is now added
+	  automatically. Introduced a new header file debug.h to support this
+	  and also moved ntfs_debug() function into it.
+	- Make reading of compressed files more intelligent and especially get
+	  rid of the vmalloc_nofs() from readpage(). This now uses per CPU
+	  buffers (allocated at first mount with cluster size <= 4kiB and
+	  deallocated on last umount with cluster size <= 4kiB), and
+	  asynchronous io for the compressed data using a list of buffer heads.
+	  Er, we use synchronous io as async io only works on whole pages
+	  covered by buffers and not on individual buffer heads...
+	- Bug fix for reading compressed files with sparse compression blocks.
+
+tng-0.0.2 - Now handles larger/fragmented/compressed volumes/files/dirs.
+
+	- Fixed handling of directories when cluster size exceeds index block
+	  size.
+	- Hide DOS only name space directory entries from readdir() but allow
+	  them in lookup(). This should fix the problem that Linux doesn't
+	  support directory hard links, while still allowing access to entries
+	  via their short file name. This also has the benefit of mimicking
+	  what Windows users are used to, so it is the ideal solution.
+	- Implemented sync_page everywhere so no more hangs in D state when
+	  waiting for a page.
+	- Stop using bforget() in favour of brelse().
+	- Stop locking buffers unnecessarily.
+	- Implemented compressed files (inode->mapping contains uncompressed
+	  data, raw compressed data is currently bread() into a vmalloc()ed
+	  memory buffer).
+	- Enable compressed directories. (Their index root is marked compressed
+	  to indicate that new files in that directory should be created
+	  compressed.)
+	- Use vsnprintf rather than vsprintf in the ntfs_error and ntfs_warning
+	  functions. (Thanks to Will Dyson for pointing this out.)
+	- Moved the ntfs_inode and ntfs_volume (the former ntfs_inode_info and
+	  ntfs_sb_info) out of the common inode and super_block structures and
+	  started using the generic_ip and generic_sbp pointers instead. This
+	  makes ntfs entirely private with respect to the kernel tree.
+	- Detect compiler version and abort with error message if gcc less than
+	  2.96 is used.
+	- Fix bug in name comparison function in unistr.c.
+	- Implement attribute lists part 1, the infrastructure: search contexts
+	  and operations, find_external_attr(), lookup_attr()) and make the
+	  code use the infrastructure.
+	- Fix stupid buffer overflow bug that became apparent on larger run
+	  list containing attributes.
+	- Fix bugs in readdir() that became apparent on larger directories.
+
+	The driver is now really useful and survives the test
+		find . -type f -exec md5sum "{}" \;
+	without any error messages on a over 1GiB sized partition with >16k
+	files on it, including compressed files and directories and many files
+	and directories with attribute lists.
+
+tng-0.0.1 - The first useful version.
+
+	- Added ntfs_lookup().
+	- Added default upcase generation and handling.
+	- Added compile options to be shown on module init.
+	- Many bug fixes that were "hidden" before.
+	- Update to latest kernel.
+	- Added ntfs_readdir().
+	- Added file operations for mmap(), read(), open() and llseek(). We just
+	  use the generic ones. The whole point of going through implementing
+	  readpage() methods and where possible get_block() call backs is that
+	  this allows us to make use of the generic high level methods provided
+	  by the kernel.
+
+	The driver is now actually useful! Yey. (-: It undoubtedly has got bugs
+	though and it doesn't implement accesssing compressed files yet. Also,
+	accessing files with attribute list attributes is not implemented yet
+	either. But for small or simple file systems it should work and allow
+	you to list directories, use stat on directory entries and the file
+	system, open, read, mmap and llseek around in files. A big mile stone
+	has been reached!
+
+tng-0.0.0 - Initial version tag.
+
+	Initial driver implementation. The driver can mount and umount simple
+	NTFS file systems (i.e. ones without attribute lists in the system
+	files). If the mount fails there might be problems in the error handling
+	code paths, so be warned. Otherwise it seems to be loading the system
+	files nicely and the mft record read mapping/unmapping seems to be
+	working nicely, too. Proof of inode metadata in the page cache and non-
+	resident file unnamed stream data in the page cache concepts is thus
+	complete.
+

fs/ntfs/Makefile

-# Rules for making the NTFS driver
+# Rules for making the NTFS TNG driver.
 
 O_TARGET := ntfs.o
 
-obj-y   := fs.o sysctl.o support.o util.o inode.o dir.o super.o attr.o unistr.o
+obj-y   := time.o unistr.o inode.o file.o mft.o super.o debug.o aops.o \
+		attrib.o dir.o namei.o mst.o upcase.o compress.o sysctl.o
+
 obj-m   := $(O_TARGET)
-# New version format started 3 February 2001.
-EXTRA_CFLAGS = -DNTFS_VERSION=\"1.1.21\" #-DDEBUG
+
+EXTRA_CFLAGS = -DNTFS_VERSION=\"TNG-0.0.9-WIP\"
+
+ifeq ($(CONFIG_NTFS_DEBUG),y)
+EXTRA_CFLAGS += -DDEBUG
+endif
 
 include $(TOPDIR)/Rules.make
 

fs/ntfs/aops.c

+/*
+ * aops.c - NTFS kernel address space operations and page cache handling.
+ * 	    Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/swap.h>
+#include <linux/locks.h>
+
+#include "ntfs.h"
+
+/**
+ * ntfs_file_get_block - read/create inode @ino block @blk into buffer head @bh
+ * @ino:	inode to read/create block from/onto
+ * @blk:	block number to read/create
+ * @bh:		buffer in which to return the read/created block
+ * @create:	if not zero, create the block if it doesn't exist already
+ * 
+ * ntfs_file_get_block() remaps the block number @blk of the inode @ino from
+ * file offset into disk block position and returns the result in the buffer
+ * head @bh. If the block doesn't exist and create is not zero,
+ * ntfs_file_get_block() creates the block before returning it. @blk is the
+ * file offset divided by the file system block size, as defined by the field
+ * s_blocksize in the super block reachable by @ino->i_sb.
+ *
+ * If the block doesn't exist, create is true, and the inode is marked
+ * for synchronous I/O, then we will wait for creation to complete before
+ * returning the created block (which will be zeroed). Otherwise we only
+ * schedule creation and return. - FIXME: Need to have a think whether this is
+ * really necessary. What would happen if we didn't actually write the block to
+ * disk at this stage? We would just save writing a block full of zeroes to the
+ * device. - We can always write it synchronously when the user actually writes
+ * some data into it. - But this might result in random data being returned
+ * should the computer crash. - Hmmm. - This requires more thought.
+ *
+ * Obviously the block is only created if the file system super block flag
+ * MS_RDONLY is not set and only if NTFS write support is compiled in.
+ */
+int ntfs_file_get_block(struct inode *vi, const sector_t blk,
+		struct buffer_head *bh, const int create)
+{
+	ntfs_inode *ni = NTFS_I(vi);
+	ntfs_volume *vol = ni->vol;
+	VCN vcn;
+	LCN lcn;
+	int ofs;
+	BOOL is_retry = FALSE;
+
+	//ntfs_debug("Entering for blk 0x%lx.", blk);
+	//printk(KERN_DEBUG "NTFS: " __FUNCTION__ "(): Entering for blk "
+	//		"0x%lx.\n", blk);
+
+	bh->b_dev = vi->i_dev;
+	bh->b_blocknr = -1;
+	bh->b_state &= ~(1UL << BH_Mapped);
+
+	/* Convert @blk into a virtual cluster number (vcn) and offset. */
+	vcn = (VCN)blk << vol->sb->s_blocksize_bits >> vol->cluster_size_bits;
+	ofs = ((VCN)blk << vol->sb->s_blocksize_bits) & vol->cluster_size_mask;
+
+	/* Check for initialized size overflow. */
+	if ((vcn << vol->cluster_size_bits) + ofs >= ni->initialized_size)
+		return 0;
+	/*
+	 * Further, we need to be checking i_size and be just doing the
+	 * following if it is zero or we are out of bounds:
+	 * 	bh->b_blocknr = -1UL;
+	 * 	raturn 0;
+	 * Also, we need to deal with attr->initialized_size.
+	 * Also, we need to deal with the case where the last block is
+	 * requested but it is not initialized fully, i.e. it is a partial
+	 * block. We then need to read it synchronously and fill the remainder
+	 * with zero. Can't do it other way round as reading from the block
+	 * device would result in our pre-zeroed data to be overwritten as the
+	 * whole block is loaded from disk.
+	 * Also, need to lock run_list in inode so we don't have someone
+	 * reading it at the same time as someone else writing it.
+	 */
+
+retry_remap:
+
+	/* Convert the vcn to the corresponding logical cluster number (lcn). */
+	read_lock(&ni->run_list.lock);
+	lcn = vcn_to_lcn(ni->run_list.rl, vcn);
+	read_unlock(&ni->run_list.lock);
+	/* Successful remap. */
+	if (lcn >= 0) {
+		/* Setup the buffer head to describe the correct block. */
+#if 0
+		/* Already the case when we are called. */
+		bh->b_dev = vfs_ino->i_dev;
+#endif
+		bh->b_blocknr = ((lcn << vol->cluster_size_bits) + ofs) >>
+				vol->sb->s_blocksize_bits;
+		bh->b_state |= (1UL << BH_Mapped);
+		return 0;
+	}
+	/* It is a hole. */
+	if (lcn == LCN_HOLE) {
+		if (create)
+			/* FIXME: We should instantiate the hole. */
+			return -EROFS;
+		/*
+		 * Hole. Set the block number to -1 (it is ignored but
+		 * just in case and might help with debugging).
+		 */
+		bh->b_blocknr = -1UL;
+		bh->b_state &= ~(1UL << BH_Mapped);
+		return 0;
+	}
+	/* If on first try and the run list was not mapped, map it and retry. */
+	if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
+		int err = map_run_list(ni, vcn);
+		if (!err) {
+			is_retry = TRUE;
+			goto retry_remap;
+		}
+		return err;
+	}
+	if (create)
+		/* FIXME: We might need to extend the attribute. */
+		return -EROFS;
+	/* Error. */
+	return -EIO;
+
+}
+
+/**
+ * ntfs_file_readpage - fill a @page of a @file with data from the device
+ * @file:	open file to which the page @page belongs or NULL
+ * @page:	page cache page to fill with data
+ *
+ * For non-resident attributes, ntfs_file_readpage() fills the @page of the open
+ * file @file by calling the generic block_read_full_page() function provided by
+ * the kernel which in turn invokes our ntfs_file_get_block() callback in order
+ * to create and read in the buffers associated with the page asynchronously.
+ *
+ * For resident attributes, OTOH, ntfs_file_readpage() fills @page by copying
+ * the data from the mft record (which at this stage is most likely in memory)
+ * and fills the remainder with zeroes. Thus, in this case I/O is synchronous,
+ * as even if the mft record is not cached at this point in time, we need to
+ * wait for it to be read in before we can do the copy.
+ *
+ * Return zero on success or -errno on error.
+ */
+static int ntfs_file_readpage(struct file *file, struct page *page)
+{
+	s64 attr_pos;
+	struct inode *vi;
+	ntfs_inode *ni;
+	char *page_addr;
+	u32 attr_len;
+	int err = 0;
+	attr_search_context *ctx;
+	MFT_RECORD *mrec;
+
+	//ntfs_debug("Entering for index 0x%lx.", page->index);
+	/* The page must be locked. */
+	if (!PageLocked(page))
+		PAGE_BUG(page);
+	/*
+	 * Get the VFS and ntfs inodes associated with the page. This could
+	 * be achieved by looking at f->f_dentry->d_inode, too, unless the
+	 * dentry is negative, but could it really be negative considering we
+	 * are reading from the opened file? - NOTE: We can't get it from file,
+	 * because we can use ntfs_file_readpage on inodes not representing
+	 * open files!!! So basically we never ever touch file or at least we
+	 * must check it is not NULL before doing so.
+	 */
+	vi = page->mapping->host;
+	ni = NTFS_I(vi);
+
+	/* Is the unnamed $DATA attribute resident? */
+	if (test_bit(NI_NonResident, &ni->state)) {
+		/* Attribute is not resident. */
+
+		/* If the file is encrypted, we deny access, just like NT4. */
+		if (test_bit(NI_Encrypted, &ni->state)) {
+			err = -EACCES;
+			goto unl_err_out;
+		}
+		if (!test_bit(NI_Compressed, &ni->state))
+			/* Normal data stream, use generic functionality. */
+			return block_read_full_page(page, ntfs_file_get_block);
+		/* Compressed data stream. Handled in compress.c. */
+		return ntfs_file_read_compressed_block(page);
+	}
+	/* Attribute is resident, implying it is not compressed or encrypted. */
+
+	/*
+	 * Make sure the inode doesn't disappear under us. - Shouldn't be
+	 * needed as the page is locked.
+	 */
+	// atomic_inc(&vfs_ino->i_count);
+
+	/* Map, pin and lock the mft record for reading. */
+	mrec = map_mft_record(READ, ni);
+	if (IS_ERR(mrec)) {
+		err = PTR_ERR(mrec);
+		goto dec_unl_err_out;
+	}
+
+	err = get_attr_search_ctx(&ctx, ni, mrec);
+	if (err)
+		goto unm_dec_unl_err_out;
+
+	/* Find the data attribute in the mft record. */
+	if (!lookup_attr(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx)) {
+		err = -ENOENT;
+		goto put_unm_dec_unl_err_out;
+	}
+
+	/* Starting position of the page within the attribute value. */
+	attr_pos = page->index << PAGE_CACHE_SHIFT;
+
+	/* The total length of the attribute value. */
+	attr_len = le32_to_cpu(ctx->attr->_ARA(value_length));
+
+	/* Map the page so we can access it. */
+	page_addr = kmap(page);
+	/*
+	 * TODO: Find out whether we really need to zero the page. If it is
+	 * initialized to zero already we could skip this.
+	 */
+	/* 
+	 * If we are asking for any in bounds data, copy it over, zeroing the
+	 * remainder of the page if necessary. Otherwise just zero the page.
+	 */
+	if (attr_pos < attr_len) {
+		u32 bytes = attr_len - attr_pos;
+		if (bytes > PAGE_CACHE_SIZE)
+			bytes = PAGE_CACHE_SIZE;
+		else if (bytes < PAGE_CACHE_SIZE)
+			memset(page_addr + bytes, 0, PAGE_CACHE_SIZE - bytes);
+		/* Copy the data to the page. */
+		memcpy(page_addr, attr_pos + (char*)ctx->attr +
+				le16_to_cpu(ctx->attr->_ARA(value_offset)), bytes);
+	} else
+		memset(page_addr, 0, PAGE_CACHE_SIZE);
+	kunmap(page);
+	/* We are done. */
+	SetPageUptodate(page);
+put_unm_dec_unl_err_out:
+	put_attr_search_ctx(ctx);
+unm_dec_unl_err_out:
+	/* Unlock, unpin and release the mft record. */
+	unmap_mft_record(READ, ni);
+dec_unl_err_out:
+	/* Release the inode. - Shouldn't be needed as the page is locked. */
+	// atomic_dec(&vfs_ino->i_count);
+unl_err_out:
+	UnlockPage(page);
+	return err;
+}
+
+/*
+ * Specialized get block for reading the mft bitmap. Adapted from
+ * ntfs_file_get_block.
+ */
+static int ntfs_mftbmp_get_block(ntfs_volume *vol, const sector_t blk,
+		struct buffer_head *bh)
+{
+	VCN vcn = (VCN)blk << vol->sb->s_blocksize_bits >>
+			vol->cluster_size_bits;
+	int ofs = (blk << vol->sb->s_blocksize_bits) &
+			vol->cluster_size_mask;
+	LCN lcn;
+
+	ntfs_debug("Entering for blk = 0x%lx, vcn = 0x%Lx, ofs = 0x%x.",
+			blk, (long long)vcn, ofs);
+	bh->b_dev = vol->mft_ino->i_dev;
+	bh->b_state &= ~(1UL << BH_Mapped);
+	bh->b_blocknr = -1;
+	/* Check for initialized size overflow. */
+	if ((vcn << vol->cluster_size_bits) + ofs >=
+			vol->mftbmp_initialized_size) {
+		ntfs_debug("Done.");
+		return 0;
+	}
+	read_lock(&vol->mftbmp_rl.lock);
+	lcn = vcn_to_lcn(vol->mftbmp_rl.rl, vcn);
+	read_unlock(&vol->mftbmp_rl.lock);
+	ntfs_debug("lcn = 0x%Lx.", (long long)lcn);
+	if (lcn < 0LL) {
+		ntfs_error(vol->sb, "Returning -EIO, lcn = 0x%Lx.",
+				(long long)lcn);
+		return -EIO;
+	}
+	/* Setup the buffer head to describe the correct block. */
+	bh->b_blocknr = ((lcn << vol->cluster_size_bits) + ofs) >>
+			vol->sb->s_blocksize_bits;
+	bh->b_state |= (1UL << BH_Mapped);
+	ntfs_debug("Done, bh->b_blocknr = 0x%lx.", bh->b_blocknr);
+	return 0;
+}
+
+#define MAX_BUF_PER_PAGE (PAGE_CACHE_SIZE / 512)
+
+/*
+ * Specialized readpage for accessing mft bitmap. Adapted from
+ * block_read_full_page().
+ */
+static int ntfs_mftbmp_readpage(ntfs_volume *vol, struct page *page)
+{
+	sector_t iblock, lblock;
+	struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
+	unsigned int blocksize, blocks;
+	int nr, i;
+	unsigned char blocksize_bits;
+
+	ntfs_debug("Entering for index 0x%lx.", page->index);
+	if (!PageLocked(page))
+		PAGE_BUG(page);
+	blocksize = vol->sb->s_blocksize;
+	blocksize_bits = vol->sb->s_blocksize_bits;
+	if (!page->buffers)
+		create_empty_buffers(page, blocksize);
+	head = page->buffers;
+	if (!head) {
+		ntfs_error(vol->sb, "Creation of empty buffers failed, cannot "
+				"read page.");
+		return -EINVAL;
+	}
+	blocks = PAGE_CACHE_SIZE >> blocksize_bits;
+	iblock = page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
+	lblock = (((vol->_VMM(nr_mft_records) + 7) >> 3) + blocksize - 1) >>
+			blocksize_bits;
+	ntfs_debug("blocks = 0x%x, iblock = 0x%lx, lblock = 0x%lx.", blocks,
+			iblock, lblock);
+	bh = head;
+	nr = i = 0;
+	do {
+		ntfs_debug("In do loop, i = 0x%x, iblock = 0x%lx.", i,
+				iblock);
+		if (buffer_uptodate(bh)) {
+			ntfs_debug("Buffer is already uptodate.");
+			continue;
+		}
+		if (!buffer_mapped(bh)) {
+			if (iblock < lblock) {
+				if (ntfs_mftbmp_get_block(vol, iblock, bh))
+					continue;
+			}
+			if (!buffer_mapped(bh)) {
+				ntfs_debug("Buffer is not mapped, setting "
+						"uptodate.");
+				memset(kmap(page) + i*blocksize, 0, blocksize);
+				flush_dcache_page(page);
+				kunmap(page);
+				set_bit(BH_Uptodate, &bh->b_state);
+				continue;
+			}
+			/*
+			 * ntfs_mftbmp_get_block() might have updated the
+			 * buffer synchronously.
+			 */
+			if (buffer_uptodate(bh)) {
+				ntfs_debug("Buffer is now uptodate.");
+				continue;
+			}
+		}
+		arr[nr++] = bh;
+	} while (i++, iblock++, (bh = bh->b_this_page) != head);
+	ntfs_debug("After do loop, i = 0x%x, iblock = 0x%lx, nr = 0x%x.", i,
+			iblock, nr);
+	if (!nr) {
+		/* All buffers are uptodate - set the page uptodate as well. */
+		ntfs_debug("All buffers are uptodate, returning 0.");
+		SetPageUptodate(page);
+		UnlockPage(page);
+		return 0;
+	}
+	/* Stage two: lock the buffers */
+	ntfs_debug("Locking buffers.");
+	for (i = 0; i < nr; i++) {
+		struct buffer_head *bh = arr[i];
+		lock_buffer(bh);
+		set_buffer_async_io(bh);
+	}
+	/* Stage 3: start the IO */
+	ntfs_debug("Starting IO on buffers.");
+	for (i = 0; i < nr; i++)
+		submit_bh(READ, arr[i]);
+	ntfs_debug("Done.");
+	return 0;
+}
+
+/**
+ * end_buffer_read_index_async - async io completion for reading index records
+ * @bh:		buffer head on which io is completed
+ * @uptodate:	whether @bh is now uptodate or not
+ *
+ * Asynchronous I/O completion handler for reading pages belogning to the
+ * index allocation attribute address space of directory inodes.
+ *
+ * Perform the post read mst fixups when all IO on the page has been completed
+ * and marks the page uptodate or sets the error bit on the page.
+ *
+ * Adapted from fs/buffer.c.
+ *
+ * NOTE: We use this function as async io completion handler for reading pages
+ * belonging to the mft data attribute address space, too as this saves
+ * duplicating an almost identical function. We do this by cheating a little
+ * bit in setting the index_block_size in the mft ntfs_inode to the mft record
+ * size of the volume (vol->mft_record_size), and index_block_size_bits to
+ * mft_record_size_bits, respectively.
+ */
+void end_buffer_read_index_async(struct buffer_head *bh, int uptodate)
+{
+	static spinlock_t page_uptodate_lock = SPIN_LOCK_UNLOCKED;
+	unsigned long flags;
+	struct buffer_head *tmp;
+	struct page *page;
+
+	mark_buffer_uptodate(bh, uptodate);
+
+	/* This is a temporary buffer used for page I/O. */
+	page = bh->b_page;
+	if (!uptodate)
+		SetPageError(page);
+	/*
+	 * Be _very_ careful from here on. Bad things can happen if
+	 * two buffer heads end IO at almost the same time and both
+	 * decide that the page is now completely done.
+	 *
+	 * Async buffer_heads are here only as labels for IO, and get
+	 * thrown away once the IO for this page is complete.  IO is
+	 * deemed complete once all buffers have been visited
+	 * (b_count==0) and are now unlocked. We must make sure that
+	 * only the _last_ buffer that decrements its count is the one
+	 * that unlock the page..
+	 */
+	spin_lock_irqsave(&page_uptodate_lock, flags);
+	mark_buffer_async(bh, 0);
+	unlock_buffer(bh);
+
+	tmp = bh->b_this_page;
+	while (tmp != bh) {
+		if (buffer_async(tmp) && buffer_locked(tmp))
+			goto still_busy;
+		tmp = tmp->b_this_page;
+	}
+	/* OK, the async IO on this page is complete. */
+	spin_unlock_irqrestore(&page_uptodate_lock, flags);
+	/*
+	 * If none of the buffers had errors then we can set the page uptodate,
+	 * but we first have to perform the post read mst fixups.
+	 */
+	if (!PageError(page)) {
+		char *addr;
+		unsigned int i, recs, nr_err = 0;
+		u32 rec_size;
+		ntfs_inode *ni = NTFS_I(page->mapping->host);
+
+		addr = kmap_atomic(page, KM_BIO_IRQ);
+		rec_size = ni->_IDM(index_block_size);
+		recs = PAGE_CACHE_SIZE / rec_size;
+		for (i = 0; i < recs; i++) {
+			if (!post_read_mst_fixup((NTFS_RECORD*)(addr +
+					i * rec_size), rec_size))
+				continue;
+			nr_err++;
+			ntfs_error(ni->vol->sb, "post_read_mst_fixup() failed, "
+					"corrupt %s record 0x%Lx. Run chkdsk.",
+					ni->mft_no ? "index" : "mft",
+					(long long)((page->index <<
+					PAGE_CACHE_SHIFT >>
+					ni->_IDM(index_block_size_bits)) + i));
+		}
+		kunmap_atomic(addr, KM_BIO_IRQ);
+		if (!nr_err && recs)
+			SetPageUptodate(page);
+		else {
+			ntfs_error(ni->vol->sb, "Setting page error, index "
+					"0x%lx.", page->index);
+			SetPageError(page);
+		}
+	}
+	UnlockPage(page);
+	return;
+still_busy:
+	spin_unlock_irqrestore(&page_uptodate_lock, flags);
+	return;
+}
+
+/**
+ * ntfs_dir_readpage - fill a @page of a directory with data from the device
+ * @dir:	open directory to which the page @page belongs
+ * @page:	page cache page to fill with data
+ *
+ * Fill the page @page of the open directory @dir. We read each buffer
+ * asynchronously and when all buffers are read in our io completion
+ * handler end_buffer_read_index_block_async() automatically applies the mst
+ * fixups to the page before finally marking it uptodate and unlocking it.
+ *
+ * Contains an adapted version of fs/buffer.c::block_read_full_page(), a
+ * generic "read page" function for block devices that have the normal
+ * get_block functionality. This is most of the block device filesystems.
+ * Reads the page asynchronously --- the unlock_buffer() and
+ * mark_buffer_uptodate() functions propagate buffer state into the
+ * page struct once IO has completed.
+ */
+static int ntfs_dir_readpage(struct file *dir, struct page *page)
+{
+	struct inode *vi;
+	struct super_block *sb;
+	struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
+	sector_t iblock, lblock;
+	unsigned int blocksize, blocks, nr_bu;
+	int nr, i;
+	unsigned char blocksize_bits;
+
+	/* The page must be locked. */
+	if (!PageLocked(page))
+		PAGE_BUG(page);
+	/*
+	 * Get the VFS/ntfs inodes, the super block and ntfs volume associated
+	 * with the page.
+	 */
+	vi = page->mapping->host;
+	sb = vi->i_sb;
+
+	/* We need to create buffers for the page so we can do low level io. */
+	blocksize = sb->s_blocksize;
+	blocksize_bits = sb->s_blocksize_bits;
+
+	if (!page->buffers)
+		create_empty_buffers(page, blocksize);
+	else
+		ntfs_error(sb, "Page (index 0x%lx) already has buffers.",
+				page->index);
+
+	nr_bu = blocks = PAGE_CACHE_SIZE >> blocksize_bits;
+	iblock = page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
+	lblock = (vi->i_size + blocksize - 1) >> blocksize_bits;
+
+	bh = head = page->buffers;
+	BUG_ON(!bh);
+
+	/* Loop through all the buffers in the page. */
+	i = nr = 0;
+	do {
+		if (buffer_uptodate(bh)) {
+			nr_bu--;
+			continue;
+		}
+		if (!buffer_mapped(bh)) {
+			/* Is the block within the allowed limits? */
+			if (iblock < lblock) {
+				/* Remap the inode offset to its disk block. */
+				if (ntfs_file_get_block(vi, iblock, bh, 0))
+					continue;
+			}
+			if (!buffer_mapped(bh)) {
+				/*
+				 * Error. Zero this portion of the page and set
+				 * the buffer uptodate.
+				 */
+				memset(kmap(page) + i * blocksize, 0,
+						blocksize);
+				flush_dcache_page(page);
+				kunmap(page);
+				set_bit(BH_Uptodate, &bh->b_state);
+				continue;
+			}
+			/* The buffer might have been updated synchronousle. */
+			if (buffer_uptodate(bh))
+				continue;
+		}
+		arr[nr++] = bh;
+	} while (i++, iblock++, (bh = bh->b_this_page) != head);
+
+	/* Check we have at least one buffer ready for io. */
+	if (nr) {
+		/* Lock the buffers. */
+		for (i = 0; i < nr; i++) {
+			struct buffer_head *tbh = arr[i];
+			lock_buffer(tbh);
+			tbh->b_end_io = end_buffer_read_index_async;
+			mark_buffer_async(tbh, 1);
+		}
+		/* Finally, start io on the buffers. */
+		for (i = 0; i < nr; i++)
+			submit_bh(READ, arr[i]);
+		/* We are done. */
+		return 0;
+	}
+	if (!nr_bu) {
+		ntfs_debug("All buffers in the page were already uptodate, "
+				"assuming mst fixups were already applied.");
+		SetPageUptodate(page);
+		UnlockPage(page);
+		return 0;
+	}
+	ntfs_error(sb, "No io was scheduled on any of the buffers in the page, "
+			"but buffers were not all uptodate to start with. "
+			"Setting page error flag and returning io error.");
+	SetPageError(page);
+	UnlockPage(page);
+	return -EIO;
+}
+
+/* Address space operations for accessing normal file data. */
+struct address_space_operations ntfs_file_aops = {
+	writepage:	NULL,			/* Write dirty page to disk. */
+	readpage:	ntfs_file_readpage,	/* Fill page with data. */
+	sync_page:	block_sync_page,	/* Currently, just unplugs the
+						   disk request queue. */
+	prepare_write:	NULL,			/* . */
+	commit_write:	NULL,			/* . */
+	//truncatepage:	NULL,			/* . */
+};
+
+typedef int readpage_t(struct file *, struct page *);
+
+/* FIXME: Kludge: Address space operations for accessing mftbmp. */
+struct address_space_operations ntfs_mftbmp_aops = {
+	writepage:	NULL,			/* Write dirty page to disk. */
+	readpage:	(readpage_t*)ntfs_mftbmp_readpage, /* Fill page with
+							      data. */
+	sync_page:	block_sync_page,	/* Currently, just unplugs the
+						   disk request queue. */
+	prepare_write:	NULL,			/* . */
+	commit_write:	NULL,			/* . */
+	//truncatepage:	NULL,			/* . */
+};
+
+/*
+ * Address space operations for accessing normal directory data (i.e. index
+ * allocation attribute). We can't just use the same operations as for files
+ * because 1) the attribute is different and even more importantly 2) the index
+ * records have to be multi sector transfer deprotected (i.e. fixed-up).
+ */
+struct address_space_operations ntfs_dir_aops = {
+	writepage:	NULL,			/* Write dirty page to disk. */
+	readpage:	ntfs_dir_readpage,	/* Fill page with data. */
+	sync_page:	block_sync_page,	/* Currently, just unplugs the
+						   disk request queue. */
+	prepare_write:	NULL,			/* . */
+	commit_write:	NULL,			/* . */
+	//truncatepage:	NULL,			/* . */
+};
+

fs/ntfs/attr.c

-/*
- * attr.c
- *
- * Copyright (C) 1996-1999 Martin von Lwis
- * Copyright (C) 1996-1997 Rgis Duchesne
- * Copyright (C) 1998 Joseph Malicki
- * Copyright (C) 1999 Steve Dodd
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
- */
-
-#include "ntfstypes.h"
-#include "struct.h"
-#include "attr.h"
-
-#include <linux/errno.h>
-#include <linux/ntfs_fs.h>
-#include "macros.h"
-#include "support.h"
-#include "util.h"
-#include "super.h"
-#include "inode.h"
-#include "unistr.h"
-
-/**
- * ntfs_find_attr_in_mft_rec - find attribute in mft record
- * @vol:	volume on which attr resides
- * @m:		mft record to search
- * @type:	attribute type to find
- * @name:	attribute name to find (optional, i.e. NULL means don't care)
- * @name_len:	attribute name length (only needed if @name present)
- * @ic:		ignore case if 1 or case sensitive if 0 (ignored if @name NULL)
- * @instance:	instance number to find
- *
- * Only search the specified mft record and it ignores the presence of an
- * attribute list attribute (unless it is the one being searched for,
- * obviously, in which case it is returned).
- */
-ntfs_u8* ntfs_find_attr_in_mft_rec(ntfs_volume *vol, ntfs_u8 *m, __u32 type,
-		wchar_t *name, __u32 name_len, int ic, __u16 instance)
-{
-	ntfs_u8 *a;
-	
-	/* Iterate over attributes in mft record @m. */
-	a = m + NTFS_GETU16(m + 20);	/* attrs_offset */
-	for (; a >= m && a <= m + vol->mft_record_size;
-				a += NTFS_GETU32(a + 4 /* length */)) {
-		/* We catch $END with this more general check, too... */
-		if (NTFS_GETU32(a + 0 /* type */) > type)
-			return NULL;
-		if (!NTFS_GETU32(a + 4 /* length */))
-			break;
-		if (NTFS_GETU32(a + 0 /* type */) != type)
-			continue;
-		/* If @name is present, compare the two names. */
-		if (name && !ntfs_are_names_equal(name, name_len, (wchar_t*)
-				(a + NTFS_GETU16(a + 10 /* name_offset */)),
-				a[9] /* name_length */, ic, vol->upcase,
-				vol->upcase_length)) {
-			register int rc;
-			
-			rc = ntfs_collate_names(vol->upcase, vol->upcase_length,
-					name, name_len, (wchar_t*)(a +
-					NTFS_GETU16(a + 10 /* name_offset */)),
-					a[9] /* name_length */, 1, 1);
-			/*
-			 * If @name collates before a->name, there is no
-			 * matching attribute.
-			 */
-			if (rc == -1)
-				return NULL;
-			/* If the strings are not equal, continue search. */
-			if (rc)
-	 			continue;
-			rc = ntfs_collate_names(vol->upcase, vol->upcase_length,
-					name, name_len, (wchar_t*)(a +
-					NTFS_GETU16(a + 10 /* name_offset */)),
-					a[9] /* name_length */, 0, 1);
-			if (rc == -1)
-				return NULL;
-			if (rc)
-				continue;
-		}
-		/*
-		 * The names match or @name not present. Check instance number.
-		 * and if it matches we have found the attribute and are done.
-		 */
-		if (instance != NTFS_GETU16(a + 14 /* instance */))
-			continue;
-		ntfs_debug(DEBUG_FILE3, "ntfs_find_attr_in_mft_record: found: "
-			"attr type 0x%x, instance number = 0x%x.\n",
-			NTFS_GETU32(a + 0), instance);
-		return a;
-	}
-	ntfs_error("ntfs_find_attr_in_mft_record: mft record 0x%x is corrupt"
-			". Run chkdsk.\n", m);
-	return NULL;
-}
-
-/* Look if an attribute already exists in the inode, and if not, create it. */
-int ntfs_new_attr(ntfs_inode *ino, int type, void *name, int namelen,
-		  void *value, int value_len, int *pos, int *found)
-{
-	int do_insert = 0;
-	int i, m;
-	ntfs_attribute *a;
-
-	for (i = 0; i < ino->attr_count; i++)
-	{
-		a = ino->attrs + i;
-		if (a->type < type)
-			continue;
-		if (a->type > type) {
-			do_insert = 1;
-			break;
-		}
-		/* If @name is present, compare the two names. */
-		if (namelen && !ntfs_are_names_equal((wchar_t*)name, namelen,
-				a->name, a->namelen /* name_length */,
-				1 /* ignore case*/, ino->vol->upcase,
-				ino->vol->upcase_length)) {
-			register int rc;
-
-			rc = ntfs_collate_names(ino->vol->upcase,
-					ino->vol->upcase_length, a->name,
-					a->namelen, (wchar_t*)name, namelen,
-					1 /* ignore case */, 1);
-			if (rc == -1)
-				continue;
-			if (rc == 1) {
-	 			do_insert = 1;
-				break;
-			}
-			rc = ntfs_collate_names(ino->vol->upcase,
-					ino->vol->upcase_length, a->name,
-					a->namelen, (wchar_t*)name, namelen,
-					0 /* case sensitive */, 1);
-			if (rc == -1)
-				continue;
-			if (rc == 1) {
-				do_insert = 1;
-				break;
-			}
-		}
-		/* Names are equal or no name was asked for. */
-		/* If a value was specified compare the values. */
-		if (value_len && a->resident) {
-			if (!a->resident) {
-				ntfs_error("ntfs_new_attr: Value specified but "
-					"attribute non-resident. Bug!\n");
-				return -EINVAL;
-			}
-			m = value_len;
-			if (m > a->size)
-				m = a->size;
-			m = memcmp(value, a->d.data, m);
-			if (m > 0)
-				continue;
-			if (m < 0) {
-				do_insert = 1;
-				break;
-			}
-			/* Values match until min of value lengths. */
-			if (value_len > a->size)
-				continue;
-			if (value_len < a->size) {
-				do_insert = 1;
-				break;
-			}
-		}
-		/* Full match! */
-		*found = 1;
-		*pos = i;
-		return 0;
-	}
-	/* Re-allocate space. */
-	if (ino->attr_count % 8 == 0)
-	{
-		ntfs_attribute* new;
-		new = (ntfs_attribute*)ntfs_malloc((ino->attr_count + 8) *
-							sizeof(ntfs_attribute));
-		if (!new)
-			return -ENOMEM;
-		if (ino->attrs) {
-			ntfs_memcpy(new, ino->attrs, ino->attr_count *
-							sizeof(ntfs_attribute));
-			ntfs_free(ino->attrs);
-		}
-		ino->attrs = new;
-	}
-	if (do_insert)
-		ntfs_memmove(ino->attrs + i + 1, ino->attrs + i,
-			     (ino->attr_count - i) * sizeof(ntfs_attribute));
-	ino->attr_count++;
-	ino->attrs[i].type = type;
-	ino->attrs[i].namelen = namelen;
-	ino->attrs[i].name = name;
-	*pos = i;
-	*found = 0;
-	return 0;
-}
-
-int ntfs_make_attr_resident(ntfs_inode *ino, ntfs_attribute *attr)
-{
-	__s64 size = attr->size;
-	if (size > 0) {
-		/* FIXME: read data, free clusters */
-		return -EOPNOTSUPP;
-	}
-	attr->resident = 1;
-	return 0;
-}
-
-/* Store in the inode readable information about a run. */
-int ntfs_insert_run(ntfs_attribute *attr, int cnum, ntfs_cluster_t cluster,
-		     int len)
-{
-	/* (re-)allocate space if necessary. */
-	if ((attr->d.r.len * sizeof(ntfs_runlist)) % PAGE_SIZE == 0) {
-		ntfs_runlist* new;
-		unsigned long new_size;
-
-		ntfs_debug(DEBUG_MALLOC, "ntfs_insert_run: re-allocating "
-				"space: old attr->d.r.len = 0x%x\n",
-				attr->d.r.len);
-		new_size = attr->d.r.len * sizeof(ntfs_runlist) + PAGE_SIZE;
-		if ((new_size >> PAGE_SHIFT) > num_physpages) {
-			ntfs_error("ntfs_insert_run: attempted to allocate "
-					"more pages than num_physpages."
-					"This might be a bug or a corrupt"
-					"file system.\n");
-			return -1;
-		}
-		new = ntfs_vmalloc(new_size);
-		if (!new) {
-			ntfs_error("ntfs_insert_run: ntfs_vmalloc(new_size = "
-					"0x%x) failed\n", new_size);
-			return -1;
-		}
-		if (attr->d.r.runlist) {
-			ntfs_memcpy(new, attr->d.r.runlist, attr->d.r.len
-					* sizeof(ntfs_runlist));
-			ntfs_vfree(attr->d.r.runlist);
-		}
-		attr->d.r.runlist = new;
-	}
-	if (attr->d.r.len > cnum)
-		ntfs_memmove(attr->d.r.runlist + cnum + 1,
-			     attr->d.r.runlist + cnum,
-			     (attr->d.r.len - cnum) * sizeof(ntfs_runlist));
-	attr->d.r.runlist[cnum].lcn = cluster;
-	attr->d.r.runlist[cnum].len = len;
-	attr->d.r.len++;
-	return 0;
-}
-
-/**
- * ntfs_extend_attr - extend allocated size of an attribute
- * @ino:	ntfs inode containing the attribute to extend
- * @attr:	attribute which to extend
- * @len:	desired new length for @attr (_not_ the amount to extend by)
- *
- * Extends an attribute. Allocate clusters on the volume which @ino belongs to.
- * Extends the run list accordingly, preferably by extending the last run of
- * the existing run list, first.
- *
- * Only modifies attr->allocated, i.e. doesn't touch attr->size, nor
- * attr->initialized.
- */
-int ntfs_extend_attr(ntfs_inode *ino, ntfs_attribute *attr, const __s64 len)
-{
-	int rlen, rl2_len, err = 0;
-	ntfs_cluster_t cluster, clen;
-	ntfs_runlist *rl, *rl2;
-
-	if ((attr->flags & (ATTR_IS_COMPRESSED | ATTR_IS_ENCRYPTED)) ||
-			ino->record_count > 1)
-		return -EOPNOTSUPP;
-	/*
-	 * FIXME: Don't make non-resident if the attribute type is not right.
-	 * For example cannot make index attribute non-resident! (AIA)
-	 */
-	if (attr->resident) {
-		err = ntfs_make_attr_nonresident(ino, attr);
-		if (err)
-			return err;
-	}
-	if (len <= attr->allocated)
-		return 0;	/* Truly stupid things do sometimes happen. */
-	rl = attr->d.r.runlist;
-	rlen = attr->d.r.len;
-	if (rlen > 0)
-		cluster = rl[rlen - 1].lcn + rl[rlen - 1].len;
-	else
-		/* No preference for allocation space. */
-		cluster = (ntfs_cluster_t)-1;
-	/*
-	 * Calculate the extra space we need, and round up to multiple of
-	 * cluster size to get number of new clusters needed.
-	 */
-	clen = (len - attr->allocated + ino->vol->cluster_size - 1) >>
-			ino->vol->cluster_size_bits;
-	if (!clen)
-		return 0;
-	err = ntfs_allocate_clusters(ino->vol, &cluster, &clen, &rl2,
-			&rl2_len, DATA_ZONE);
-	if (err)
-		return err;
-	attr->allocated += (__s64)clen << ino->vol->cluster_size_bits;
-	if (rlen > 0) {
-		err = splice_runlists(&rl, &rlen, rl2, rl2_len);
-		ntfs_vfree(rl2);
-		if (err)
-			return err;
-	} else {
-		if (rl)
-			ntfs_vfree(rl);
-		rl = rl2;
-		rlen = rl2_len;
-	}
-	attr->d.r.runlist = rl;
-	attr->d.r.len = rlen;
-	return 0;
-}
-
-int ntfs_make_attr_nonresident(ntfs_inode *ino, ntfs_attribute *attr)
-{
-	int error;
-	ntfs_io io;
-	void *data = attr->d.data;
-	__s64 len = attr->size;
-
-	attr->d.r.len = 0;
-	attr->d.r.runlist = NULL;
-	attr->resident = 0;
-	/*
-	 * ->allocated is updated by ntfs_extend_attr(), while ->initialized
-	 * and ->size are updated by ntfs_readwrite_attr(). (AIA)
-	 */
-	attr->allocated = attr->initialized = 0;
-	error = ntfs_extend_attr(ino, attr, len);
-	if (error)
-		return error; /* FIXME: On error, restore old values. */
-	io.fn_put = ntfs_put;
-	io.fn_get = ntfs_get;
-	io.param = data;
-	io.size = len;
-	io.do_read = 0;
-	return ntfs_readwrite_attr(ino, attr, 0, &io);
-}
-
-int ntfs_attr_allnonresident(ntfs_inode *ino)
-{
-	int i, error = 0;
-        ntfs_volume *vol = ino->vol;
-
-	for (i = 0; !error && i < ino->attr_count; i++)
-	{
-		if (ino->attrs[i].type != vol->at_security_descriptor &&
-		    ino->attrs[i].type != vol->at_data)
-			continue;
-		error = ntfs_make_attr_nonresident(ino, ino->attrs + i);
-	}
-	return error;
-}
-
-/*
- * Resize the attribute to a newsize. attr->allocated and attr->size are
- * updated, but attr->initialized is not changed unless it becomes bigger than
- * attr->size, in which case it is set to attr->size.
- */
-int ntfs_resize_attr(ntfs_inode *ino, ntfs_attribute *attr, __s64 newsize)
-{
-	int error = 0;
-	__s64 oldsize = attr->size;
-	int clustersizebits = ino->vol->cluster_size_bits;
-	int i, count, newcount;
-	ntfs_runlist *rl, *rlt;
-
-	if (newsize == oldsize)
-		return 0;
-	if (attr->flags & (ATTR_IS_COMPRESSED | ATTR_IS_ENCRYPTED))
-		return -EOPNOTSUPP;
-	if (attr->resident) {
-		void *v;
-		if (newsize > ino->vol->mft_record_size) {
-			error = ntfs_make_attr_nonresident(ino, attr);
-			if (error)
-				return error;
-			return ntfs_resize_attr(ino, attr, newsize);
-		}
-		v = attr->d.data;
-		if (newsize) {
-			__s64 minsize = newsize;
-			attr->d.data = ntfs_malloc(newsize);
-			if (!attr->d.data) {
-				ntfs_free(v);
-				return -ENOMEM;
-			}
-			if (newsize > oldsize) {
-				minsize = oldsize;
-				ntfs_bzero((char*)attr->d.data + oldsize,
-					   newsize - oldsize);
-			}
-			ntfs_memcpy((char*)attr->d.data, v, minsize);
-		} else
-			attr->d.data = 0;
-		ntfs_free(v);
-		attr->size = newsize;
-		return 0;
-	}
-	/* Non-resident attribute. */
-	rl = attr->d.r.runlist;
-	if (newsize < oldsize) {
-		int rl_size;
-		/*
-		 * FIXME: We might be going awfully wrong for newsize = 0,
-		 * possibly even leaking memory really badly. But considering
-		 * in that case there is more breakage due to -EOPNOTSUPP stuff
-		 * further down the code path, who cares for the moment... (AIA)
-		 */
-		for (i = 0, count = 0; i < attr->d.r.len; i++) {
-			if ((__s64)(count + rl[i].len) << clustersizebits >
-					newsize) {
-				i++;
-				break;
-			}
-			count += (int)rl[i].len;
-		}
-		newcount = count;
-		/* Free unused clusters in current run, unless sparse. */
-		if (rl[--i].lcn != (ntfs_cluster_t)-1) {
-			ntfs_cluster_t rounded = newsize - ((__s64)count <<
-					clustersizebits);
-			rounded = (rounded + ino->vol->cluster_size - 1) >>
-					clustersizebits;
-			error = ntfs_deallocate_cluster_run(ino->vol, 
-					rl[i].lcn + rounded,
-					rl[i].len - rounded);
-			if (error)
-				return error; /* FIXME: Incomplete operation. */
-			rl[i].len = rounded;
-			newcount = count + rounded;
-		}
-		/* Free all other runs. */
-		i++;
-		error = ntfs_deallocate_clusters(ino->vol, rl + i,
-				attr->d.r.len - i);
-		if (error)
-			return error; /* FIXME: Incomplete operation. */
-		/*
-		 * Free space for extra runs in memory if enough memory left
-		 * to do so. FIXME: Only do it if it would free memory. (AIA)
-		 */
-		rl_size = ((i + 1) * sizeof(ntfs_runlist) + PAGE_SIZE - 1) &
-				PAGE_MASK;
-		if (rl_size < ((attr->d.r.len * sizeof(ntfs_runlist) +
-				PAGE_SIZE - 1) & PAGE_MASK)) {
-			rlt = ntfs_vmalloc(rl_size);
-			if (rlt) {
-				ntfs_memcpy(rlt, rl, i * sizeof(ntfs_runlist));
-				ntfs_vfree(rl);
-				attr->d.r.runlist = rl = rlt;
-			}
-		}
-		rl[i].lcn = (ntfs_cluster_t)-1;
-		rl[i].len = (ntfs_cluster_t)0;
-		attr->d.r.len = i;
-	} else {
-		error = ntfs_extend_attr(ino, attr, newsize);
-		if (error)
-			return error; /* FIXME: Incomplete operation. */
-		newcount = (newsize + ino->vol->cluster_size - 1) >>
-				clustersizebits;
-	}
-	/* Fill in new sizes. */
-	attr->allocated = (__s64)newcount << clustersizebits;
-	attr->size = newsize;
-	if (attr->initialized > newsize)
-		attr->initialized = newsize;
-	if (!newsize)
-		error = ntfs_make_attr_resident(ino, attr);
-	return error;
-}
-
-int ntfs_create_attr(ntfs_inode *ino, int anum, char *aname, void *data,
-		int dsize, ntfs_attribute **rattr)
-{
-	void *name;
-	int namelen;
-	int found, i;
-	int error;
-	ntfs_attribute *attr;
-	
-	if (dsize > ino->vol->mft_record_size)
-		/* FIXME: Non-resident attributes. */
-		return -EOPNOTSUPP;
-	if (aname) {
-		namelen = strlen(aname);
-		name = ntfs_malloc(2 * namelen);
-		if (!name)
-			return -ENOMEM;
-		ntfs_ascii2uni(name, aname, namelen);
-	} else {
-		name = 0;
-		namelen = 0;
-	}
-	error = ntfs_new_attr(ino, anum, name, namelen, data, dsize, &i,
-			&found);
-	if (error || found) {
-		ntfs_free(name);
-		return error ? error : -EEXIST;
-	}
-	*rattr = attr = ino->attrs + i;
-	/* Allocate a new number.
-	 * FIXME: Should this happen on inode writeback?
-	 * FIXME: Extension records not supported. */
-	error = ntfs_allocate_attr_number(ino, &i);
-	if (error)
-		return error;
-	attr->attrno = i;
-	if (attr->attrno + 1 != NTFS_GETU16(ino->attr + 0x28))
-		ntfs_error("UH OH! attr->attrno (%i) != NTFS_GETU16(ino->attr "
-				"+ 0x28) (%i)\n", attr->attrno,
-				NTFS_GETU16(ino->attr + 0x28));
-	attr->resident = 1;
-	attr->flags = 0;
-	attr->cengine = 0;
-	attr->size = attr->allocated = attr->initialized = dsize;
-
-	/* FIXME: INDEXED information should come from $AttrDef
-	 * Currently, only file names are indexed. As of NTFS v3.0 (Win2k),
-	 * this is no longer true. Different attributes can be indexed now. */
-	if (anum == ino->vol->at_file_name)
-		attr->indexed = 1;
-	else
-		attr->indexed = 0;
-	attr->d.data = ntfs_malloc(dsize);
-	if (!attr->d.data)
-		return -ENOMEM;
-	ntfs_memcpy(attr->d.data, data, dsize);
-	return 0;
-}
-
-/*
- * Non-resident attributes are stored in runs (intervals of clusters).
- *
- * This function stores in the inode readable information about a non-resident
- * attribute.
- */
-static int ntfs_process_runs(ntfs_inode *ino, ntfs_attribute* attr,
-		unsigned char *data)
-{
-	int startvcn, endvcn;
-	int vcn, cnum;
-	ntfs_cluster_t cluster;
-	int len, ctype;
-	int er = 0;
-	startvcn = NTFS_GETS64(data + 0x10);
-	endvcn = NTFS_GETS64(data + 0x18);
-
-	/* Check whether this chunk really belongs to the end. Problem with
-	 * this: this functions can get called on the last extent first, before
-	 * it is called on the other extents in sequence. This happens when the
-	 * base mft record contains the last extent instead of the first one
-	 * and the first extent is stored, like any intermediate extents in
-	 * extension mft records. This would be difficult to allow the way the
-	 * runlist is stored in memory. Thus we fix elsewhere by causing the
-	 * attribute list attribute to be processed immediately when found. The
-	 * extents will then be processed starting with the first one. */
-	for (cnum = 0, vcn = 0; cnum < attr->d.r.len; cnum++)
-		vcn += attr->d.r.runlist[cnum].len;
-	if (vcn != startvcn) {
-		ntfs_debug(DEBUG_FILE3, "ntfs_process_runs: ino = 0x%x, "
-			"attr->type = 0x%x, startvcn = 0x%x, endvcn = 0x%x, "
-			"vcn = 0x%x, cnum = 0x%x\n", ino->i_number, attr->type,
-			startvcn, endvcn, vcn, cnum);
-		if (vcn < startvcn) {
-			ntfs_error("Problem with runlist in extended record\n");
-			return -1;
-		}
-		/* Tried to insert an already inserted runlist. */
-		return 0;
-	}
-	if (!endvcn) {
-		if (!startvcn) {
-			/* Allocated length. */
-			endvcn = NTFS_GETS64(data + 0x28) - 1;
-			endvcn >>= ino->vol->cluster_size_bits;
-		} else {
-			/* This is an extent. Allocated length is not defined!
-			 * Extents must have an endvcn though so this is an
-			 * error. */
-			ntfs_error("Corrupt attribute extent. (endvcn is "
-				"missing)\n");
-			return -1;
-		}
-	}
-	data = data + NTFS_GETU16(data + 0x20);
-	cnum = attr->d.r.len;
-	cluster = 0;
-	for (vcn = startvcn; vcn <= endvcn; vcn += len)	{
-		if (ntfs_decompress_run(&data, &len, &cluster, &ctype)) {
-			ntfs_debug(DEBUG_FILE3, "ntfs_process_runs: "
-				"ntfs_decompress_run failed. i_number = 0x%x\n",
-				ino->i_number);
-			return -1;
-		}
-		if (ctype)
-			er = ntfs_insert_run(attr, cnum, -1, len);
-		else
-			er = ntfs_insert_run(attr, cnum, cluster, len);
-		if (er)
-			break;
-		cnum++;
-	}
-	if (er)
-		ntfs_error("ntfs_process_runs: ntfs_insert_run failed\n");
-	ntfs_debug(DEBUG_FILE3, "ntfs_process_runs: startvcn = 0x%x, vcn = 0x%x"
-				", endvcn = 0x%x, cnum = %i\n", startvcn, vcn,
-				endvcn, cnum);
-	return er;
-}
-  
-/* Insert the attribute starting at attr in the inode ino. */
-int ntfs_insert_attribute(ntfs_inode *ino, unsigned char *attrdata)
-{
-	int i, found;
-	int type;
-	short int *name;
-	int namelen;
-	void *data;
-	ntfs_attribute *attr;
-	int error;
-
-	type = NTFS_GETU32(attrdata);
-	namelen = NTFS_GETU8(attrdata + 9);
-	ntfs_debug(DEBUG_FILE3, "ntfs_insert_attribute: ino->i_number 0x%x, "
-			"attr type 0x%x\n", ino->i_number, type);
-	/* Read the attribute's name if it has one. */
-	if (!namelen)
-		name = 0;
-	else {
-		/* 1 Unicode character fits in 2 bytes. */
-		name = ntfs_malloc(2 * namelen);
-		if (!name)
-			return -ENOMEM;
-		ntfs_memcpy(name, attrdata + NTFS_GETU16(attrdata + 10),
-			    2 * namelen);
-	}
-	/* If resident look for value, too. */
-	if (NTFS_GETU8(attrdata + 8) == 0)
-		error = ntfs_new_attr(ino, type, name, namelen,
-				attrdata + NTFS_GETU16(attrdata + 0x14),
-				NTFS_GETU16(attrdata + 0x10), &i, &found);
-	else
-		error = ntfs_new_attr(ino, type, name, namelen, NULL, 0, &i,
-				&found);
-	if (error) {
-		ntfs_debug(DEBUG_FILE3, "ntfs_insert_attribute: ntfs_new_attr "
-				"failed.\n");
-		if (name)
-			ntfs_free(name);
-		return error;
-	}
-	if (found) {
-		/* It's already there, if not resident just process the runs. */
-		if (!ino->attrs[i].resident) {
-			ntfs_debug(DEBUG_FILE3, "ntfs_insert_attribute:"
-						" processing runs 1.\n");
-			/* FIXME: Check error code! (AIA) */
-			ntfs_process_runs(ino, ino->attrs + i, attrdata);
-		}
-		return 0;
-	}
-	attr = ino->attrs + i;
-	attr->resident = NTFS_GETU8(attrdata + 8) == 0;
-	attr->flags = *(__u16*)(attrdata + 0xC);
-	attr->attrno = NTFS_GETU16(attrdata + 0xE);
-  
-	if (attr->resident) {
-		attr->size = NTFS_GETU16(attrdata + 0x10);
-		data = attrdata + NTFS_GETU16(attrdata + 0x14);
-		attr->d.data = (void*)ntfs_malloc(attr->size);
-		if (!attr->d.data)
-			return -ENOMEM;
-		ntfs_memcpy(attr->d.data, data, attr->size);
-		attr->indexed = NTFS_GETU8(attrdata + 0x16);
-	} else {
-		attr->allocated = NTFS_GETS64(attrdata + 0x28);
-		attr->size = NTFS_GETS64(attrdata + 0x30);
-		attr->initialized = NTFS_GETS64(attrdata + 0x38);
-		attr->cengine = NTFS_GETU16(attrdata + 0x22);
-		if (attr->flags & ATTR_IS_COMPRESSED)
-			attr->compsize = NTFS_GETS64(attrdata + 0x40);
-		ntfs_debug(DEBUG_FILE3, "ntfs_insert_attribute: "
-			"attr->allocated = 0x%Lx, attr->size = 0x%Lx, "
-			"attr->initialized = 0x%Lx\n", attr->allocated,
-			attr->size, attr->initialized);
-		ino->attrs[i].d.r.runlist = 0;
-		ino->attrs[i].d.r.len = 0;
-		ntfs_debug(DEBUG_FILE3, "ntfs_insert_attribute: processing "
-				"runs 2.\n");
-		/* FIXME: Check error code! (AIA) */
-		ntfs_process_runs(ino, attr, attrdata);
-	}
-	return 0;
-}
-
-int ntfs_read_zero(ntfs_io *dest, int size)
-{
-	int i;
-	char *sparse = ntfs_calloc(512);
-	if (!sparse)
-		return -ENOMEM;
-	i = 512;
-	while (size) {
-		if (i > size)
-			i = size;
-		dest->fn_put(dest, sparse, i);
-		size -= i;
-	}
-	ntfs_free(sparse);
-	return 0;
-}
-
-/* Process compressed attributes. */
-int ntfs_read_compressed(ntfs_inode *ino, ntfs_attribute *attr, __s64 offset,
-			 ntfs_io *dest)
-{
-	int error = 0;
-	int clustersizebits;
-	int s_vcn, rnum, vcn, got, l1;
-	__s64 copied, len, chunk, offs1, l, chunk2;
-	ntfs_cluster_t cluster, cl1;
-	char *comp = 0, *comp1;
-	char *decomp = 0;
-	ntfs_io io;
-	ntfs_runlist *rl;
-
-	l = dest->size;
-	clustersizebits = ino->vol->cluster_size_bits;
-	/* Starting cluster of potential chunk. There are three situations:
-	   a) In a large uncompressible or sparse chunk, s_vcn is in the middle
-	      of a run.
-	   b) s_vcn is right on a run border.
-	   c) When several runs make a chunk, s_vcn is before the chunks. */
-	s_vcn = offset >> clustersizebits;
-	/* Round down to multiple of 16. */
-	s_vcn &= ~15;
-	rl = attr->d.r.runlist;
-	for (rnum = vcn = 0; rnum < attr->d.r.len && vcn + rl->len <= s_vcn;
-								rnum++, rl++)
-		vcn += rl->len;
-	if (rnum == attr->d.r.len) {
-		/* Beyond end of file. */
-		/* FIXME: Check allocated / initialized. */
-		dest->size = 0;
-		return 0;
-	}
-	io.do_read = 1;
-	io.fn_put = ntfs_put;
-	io.fn_get = 0;
-	cluster = rl->lcn;
-	len = rl->len;
-	copied = 0;
-	while (l) {
-		chunk = 0;
-		if (cluster == (ntfs_cluster_t)-1) {
-			/* Sparse cluster. */
-			__s64 ll;
-
-			if ((len - (s_vcn - vcn)) & 15)
-				ntfs_error("Unexpected sparse chunk size.");
-			ll = ((__s64)(vcn + len) << clustersizebits) - offset;
-			if (ll > l)
-				ll = l;
-			chunk = ll;
-			error = ntfs_read_zero(dest, ll);
-			if (error)
-				goto out;
-		} else if (dest->do_read) {
-			if (!comp) {
-				comp = ntfs_malloc(16 << clustersizebits);
-				if (!comp) {
-					error = -ENOMEM;
-					goto out;
-				}
-			}
-			got = 0;
-			/* We might need to start in the middle of a run. */
-			cl1 = cluster + s_vcn - vcn;
-			comp1 = comp;
-			do {
-				int delta;
-
-				io.param = comp1;
-				delta = s_vcn - vcn;
-				if (delta < 0)
-					delta = 0;
-				l1 = len - delta;
-				if (l1 > 16 - got)
-					l1 = 16 - got;
-				io.size = (__s64)l1 << clustersizebits;
-				error = ntfs_getput_clusters(ino->vol, cl1, 0,
-					       		     &io);
-				if (error)
-					goto out;
-				if (l1 + delta == len) {
-					rnum++;
-					rl++;
-					vcn += len;
-					cluster = cl1 = rl->lcn;
-					len = rl->len;
-				}
-				got += l1;
-				comp1 += (__s64)l1 << clustersizebits;
-			} while (cluster != (ntfs_cluster_t)-1 && got < 16);
-							/* Until empty run. */
-			chunk = 16 << clustersizebits;
-			if (cluster != (ntfs_cluster_t)-1 || got == 16)
-				/* Uncompressible */
-				comp1 = comp;
-			else {
-				if (!decomp) {
-					decomp = ntfs_malloc(16 << 
-							clustersizebits);
-					if (!decomp) {
-						error = -ENOMEM;
-						goto out;
-					}
-				}
-				/* Make sure there are null bytes after the
-				 * last block. */
-				*(ntfs_u32*)comp1 = 0;
-				ntfs_decompress(decomp, comp, chunk);
-				comp1 = decomp;
-			}
-			offs1 = offset - ((__s64)s_vcn << clustersizebits);
-			chunk2 = (16 << clustersizebits) - offs1;
-			if (chunk2 > l)
-				chunk2 = l;
-			if (chunk > chunk2)
-				chunk = chunk2;
-			dest->fn_put(dest, comp1 + offs1, chunk);
-		}
-		l -= chunk;
-		copied += chunk;
-		offset += chunk;
-		s_vcn = (offset >> clustersizebits) & ~15;
-		if (l && offset >= ((__s64)(vcn + len) << clustersizebits)) {
-			rnum++;
-			rl++;
-			vcn += len;
-			cluster = rl->lcn;
-			len = rl->len;
-		}
-	}
-out:
-	if (comp)
-		ntfs_free(comp);
-	if (decomp)
-		ntfs_free(decomp);
-	dest->size = copied;
-	return error;
-}
-
-int ntfs_write_compressed(ntfs_inode *ino, ntfs_attribute *attr, __s64 offset,
-		ntfs_io *dest)
-{
-	return -EOPNOTSUPP;
-}
-

fs/ntfs/attr.h

-/*
- * attr.h -  Header file for attr.c
- *
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (c) 2001 Anton Altaparmakov (AIA)
- */
-#include <linux/nls.h>
-
-ntfs_u8* ntfs_find_attr_in_mft_rec(ntfs_volume *vol, ntfs_u8 *m, __u32 type,
-			wchar_t *name, __u32 name_len, int ic, __u16 instance);
-
-int ntfs_extend_attr(ntfs_inode *ino, ntfs_attribute *attr, const __s64 len);
-
-int ntfs_resize_attr(ntfs_inode *ino, ntfs_attribute *attr, __s64 newsize);
-
-int ntfs_insert_attribute(ntfs_inode *ino, unsigned char* attrdata);
-
-int ntfs_read_compressed(ntfs_inode *ino, ntfs_attribute *attr, __s64 offset,
-			 ntfs_io *dest);
-
-int ntfs_write_compressed(ntfs_inode *ino, ntfs_attribute *attr, __s64 offset,
-			  ntfs_io *dest);
-
-int ntfs_create_attr(ntfs_inode *ino, int anum, char *aname, void *data,
-		     int dsize, ntfs_attribute **rattr);
-
-int ntfs_read_zero(ntfs_io *dest, int size);
-
-int ntfs_make_attr_nonresident(ntfs_inode *ino, ntfs_attribute *attr);
-
-int ntfs_attr_allnonresident(ntfs_inode *ino);
-
-int ntfs_new_attr(ntfs_inode *ino, int type, void *name, int namelen,
-		  void *value, int value_len, int *pos, int *found);
-
-int ntfs_insert_run(ntfs_attribute *attr, int cnum, ntfs_cluster_t cluster,
-		     int len);
-

fs/ntfs/attraops.c

+#include "ntfs.h"
+
+/*
+ * We need to define the attribute object structure. FIXME: Move these to
+ * ntfs.h.
+ */
+typedef struct {
+	ntfs_inode *a_ni;
+	ntfs_volume *a_vol;
+	atomic_t a_count;
+	s64 a_size;
+	struct rw_semaphore a_sem;
+	struct address_space a_mapping;
+	unsigned long a_flags;
+} attr_obj;
+
+/**
+ * ntfs_attr_readpage - fill a page @page of an attribute object @aobj with data
+ * @aobj:	attribute object to which the page @page belongs
+ * @page:	page cache page to fill with data
+ *
+ */
+//static int ntfs_attr_readpage(attr_obj *aobj, struct page *page)
+static int ntfs_attr_readpage(struct file *aobj, struct page *page)
+{
+	return -EOPNOTSUPP;
+}
+
+/*
+ * Address space operations for accessing attributes. Note that these functions
+ * do not accept an inode as the first parameter but an attribute object. We
+ * use this to implement a generic interface that is not bound to inodes in
+ * order to support multiple named streams per file, multiple bitmaps per file
+ * and directory, etc. Basically, this gives access to any attribute within an
+ * mft record.
+ *
+ * We make use of a slab cache for attribute object allocations.
+ */
+struct address_space_operations ntfs_attr_aops = {
+	writepage:	NULL,			/* Write dirty page to disk. */
+	readpage:	ntfs_attr_readpage,	/* Fill page with data. */
+	sync_page:	block_sync_page,	/* Currently, just unplugs the
+						   disk request queue. */
+	prepare_write:	NULL,			/* . */
+	commit_write:	NULL,			/* . */
+	//truncatepage:	NULL,			/* . */
+};
+

fs/ntfs/attrib.c

+/**
+ * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "ntfs.h"
+
+/* Temporary helper functions -- might become macros */
+
+/**
+ * rl_mm - run_list memmove
+ *
+ * It is up to the caller to serialize access to the run list @base.
+ */
+static inline void rl_mm(run_list_element *base, int dst, int src, int size)
+{
+	if ((dst != src) && (size > 0))
+		memmove (base + dst, base + src, size * sizeof (*base));
+}
+
+/**
+ * rl_mc - run_list memory copy
+ *
+ * It is up to the caller to serialize access to the run lists @dstbase and
+ * @srcbase.
+ */
+static inline void rl_mc(run_list_element *dstbase, int dst,
+		run_list_element *srcbase, int src, int size)
+{
+	if (size > 0)
+		memcpy (dstbase+dst, srcbase+src, size * sizeof (*dstbase));
+}
+
+/**
+ * ntfs_rl_realloc - Reallocate memory for run_lists
+ * @orig:  The original memory allocation
+ * @old:   The number of run_lists in the original
+ * @new:   The number of run_lists we need space for
+ *
+ * As the run_lists grow, more memory will be required.  To prevent the
+ * kernel having to allocate and reallocate large numbers of small bits of
+ * memory, this function returns and entire page of memory.
+ *
+ * It is up to the caller to serialize access to the run list @orig.
+ *
+ * N.B.  If the new allocation doesn't require a different number of pages in
+ *       memory, the function will return the original pointer.
+ *
+ * Return: Pointer  The newly allocated, or recycled,  memory.
+ *
+ * Errors: -ENOMEM, Not enough memory to allocate run list array.
+ *         -EINVAL, Invalid parameters were passed in.
+ */
+static inline run_list_element *ntfs_rl_realloc(run_list_element *orig,
+		int old, int new)
+{
+	run_list_element *nrl;
+
+	old = PAGE_ALIGN (old * sizeof (*orig));
+	new = PAGE_ALIGN (new * sizeof (*orig));
+	if (old == new)
+		return orig;
+
+	nrl = ntfs_malloc_nofs (new);
+	if (!nrl)
+		return ERR_PTR (-ENOMEM);
+
+	if (orig) {
+		memcpy (nrl, orig, min (old, new));
+		ntfs_free (orig);
+	}
+	return nrl;
+}
+
+/**
+ * ntfs_rl_merge - Join together two run_lists
+ * @one:  The first run_list and destination
+ * @two:  The second run_list
+ *
+ * If possible merge together two run_lists.  For this, their VCNs and LCNs
+ * must be adjacent.
+ *
+ * It is up to the caller to serialize access to the run lists @one and @two.
+ *
+ * Return: TRUE   Success, the run_lists were merged
+ *         FALSE  Failure, the run_lists were not merged
+ */
+static inline BOOL ntfs_rl_merge(run_list_element *one, run_list_element *two)
+{
+	BUG_ON (!one || !two);
+
+	if ((one->lcn < 0) || (two->lcn < 0))     /* Are we merging holes? */
+		return FALSE;
+	if ((one->lcn + one->length) != two->lcn) /* Are the runs contiguous? */
+		return FALSE;
+	if ((one->vcn + one->length) != two->vcn) /* Are the runs misaligned? */
+		return FALSE;
+
+	one->length += two->length;
+	return TRUE;
+}
+
+/**
+ * ntfs_rl_append - Append a run_list after the given element
+ * @orig:   The original run_list to be worked on.
+ * @osize:  The number of elements in @orig (including end marker).
+ * @new:    The run_list to be inserted.
+ * @nsize:  The number of elements in @new (excluding end marker).
+ * @loc:    Append the new run_list after this element in @orig.
+ *
+ * Append a run_list after element @loc in @orig.  Merge the right end of
+ * the new run_list, if necessary.  Adjust the size of the hole before the
+ * appended run_list.
+ *
+ * It is up to the caller to serialize access to the run lists @orig and @new.
+ *
+ * Return: Pointer, The new, combined, run_list
+ *
+ * Errors: -ENOMEM, Not enough memory to allocate run list array.
+ *         -EINVAL, Invalid parameters were passed in.
+ */
+static inline run_list_element *ntfs_rl_append(run_list_element *orig,
+		int osize, run_list_element *new, int nsize, int loc)
+{
+	run_list_element *res;
+	BOOL right;
+
+	BUG_ON (!orig || !new);
+
+	/* First, merge the right hand end, if necessary. */
+	right = ntfs_rl_merge (new + nsize - 1, orig + loc + 1);
+
+	/* Space required: Orig size + New size, less one if we merged. */
+	res = ntfs_rl_realloc (orig, osize, osize + nsize - right);
+	if (IS_ERR (res))
+		return res;
+
+	/* Move the tail of Orig out of the way, then copy in New. */
+	rl_mm (res, loc + 1 + nsize, loc + 1 + right, osize - loc - 1 - right);
+	rl_mc (res, loc + 1, new, 0, nsize);
+
+	/* Adjust the size of the preceding hole. */
+	res[loc].length = res[loc+1].vcn - res[loc].vcn;
+
+	/* We may have changed the length of the file, so fix the end marker */
+	if (res[loc+nsize+1].lcn == LCN_ENOENT)
+		res[loc+nsize+1].vcn = res[loc+nsize].vcn + res[loc+nsize].length;
+
+	return res;
+}
+
+/**
+ * ntfs_rl_insert - Insert a run_list into another
+ * @orig:   The original run_list to be worked on.
+ * @osize:  The number of elements in @orig (including end marker).
+ * @new:    The run_list to be inserted.
+ * @nsize:  The number of elements in @new (excluding end marker).
+ * @loc:    Insert the new run_list before this element in @orig.
+ *
+ * Insert a run_list before element @loc in @orig.  Merge the left end of
+ * the new run_list, if necessary.  Adjust the size of the hole after the
+ * inserted run_list.
+ *
+ * It is up to the caller to serialize access to the run lists @orig and @new.
+ *
+ * Return: Pointer, The new, combined, run_list
+ *
+ * Errors: -ENOMEM, Not enough memory to allocate run list array.
+ *         -EINVAL, Invalid parameters were passed in.
+ */
+static inline run_list_element *ntfs_rl_insert(run_list_element *orig,
+		int osize, run_list_element *new, int nsize, int loc)
+{
+	run_list_element *res;
+	BOOL left = FALSE;
+	BOOL disc = FALSE;	/* Discontinuity */
+	BOOL hole = FALSE;	/* Following a hole */
+
+	BUG_ON (!orig || !new);
+
+	/* disc => Discontinuity between the end of Orig and the start of New.
+	 *         This means we might need to insert a hole.
+	 * hole => Orig ends with a hole or an unmapped region which we can
+	 *         extend to match the discontinuity. */
+	if (loc == 0) {
+		disc = (new[0].vcn > 0);
+	} else {
+		left = ntfs_rl_merge (orig + loc - 1, new);
+
+		disc = (new[0].vcn > (orig[loc-1].vcn + orig[loc-1].length));
+		if (disc)
+			hole = (orig[loc-1].lcn == LCN_HOLE);
+	}
+
+	/* Space required: Orig size + New size, less one if we merged,
+	 * plus one if there was a discontinuity, less one for a trailing hole */
+	res = ntfs_rl_realloc (orig, osize, osize + nsize - left + disc - hole);
+	if (IS_ERR (res))
+		return res;
+
+	/* Move the tail of Orig out of the way, then copy in New. */
+	rl_mm (res, loc + nsize - left + disc - hole, loc, osize - loc);
+	rl_mc (res, loc + disc - hole, new, left, nsize - left);
+
+	/* Adjust the VCN of the last run ... */
+	if (res[loc+nsize-left+disc-hole].lcn <= LCN_HOLE) {
+		res[loc+nsize-left+disc-hole].vcn =
+			res[loc+nsize-left+disc-hole-1].vcn +
+			res[loc+nsize-left+disc-hole-1].length;
+	}
+	/* ... and the length. */
+	if ((res[loc+nsize-left+disc-hole].lcn == LCN_HOLE) ||
+	    (res[loc+nsize-left+disc-hole].lcn == LCN_RL_NOT_MAPPED)) {
+		res[loc+nsize-left+disc-hole].length =
+			res[loc+nsize-left+disc-hole+1].vcn -
+			res[loc+nsize-left+disc-hole].vcn;
+	}
+
+	/* Writing beyond the end of the file and there's a discontinuity. */
+	if (disc) {
+		if (hole) {
+			res[loc-1].length = res[loc].vcn - res[loc-1].vcn;
+		} else {
+			if (loc > 0) {
+				res[loc].vcn = res[loc-1].vcn +
+					res[loc-1].length;
+				res[loc].length = res[loc+1].vcn - res[loc].vcn;
+			} else {
+				res[loc].vcn = 0;
+				res[loc].length = res[loc+1].vcn;
+			}
+			res[loc].lcn = LCN_RL_NOT_MAPPED;
+		}
+
+		if (res[loc+nsize-left+disc].lcn == LCN_ENOENT)
+			res[loc+nsize-left+disc].vcn = res[loc+nsize-left+disc-1].vcn +
+				res[loc+nsize-left+disc-1].length;
+	}
+
+	return res;
+}
+
+/**
+ * ntfs_rl_replace - Overwrite a run_list element with another run_list
+ * @orig:   The original run_list to be worked on.
+ * @osize:  The number of elements in @orig (including end marker).
+ * @new:    The run_list to be inserted.
+ * @nsize:  The number of elements in @new (excluding end marker).
+ * @loc:    Index of run_list @orig to overwrite with @new.
+ *
+ * Replace the run_list at @loc with @new.  Merge the left and right ends of
+ * the inserted run_list, if necessary.
+ *
+ * It is up to the caller to serialize access to the run lists @orig and @new.
+ *
+ * Return: Pointer, The new, combined, run_list
+ *
+ * Errors: -ENOMEM, Not enough memory to allocate run list array.
+ *         -EINVAL, Invalid parameters were passed in.
+ */
+static inline run_list_element *ntfs_rl_replace(run_list_element *orig,
+		int osize, run_list_element *new, int nsize, int loc)
+{
+	run_list_element *res;
+	BOOL left = FALSE;
+	BOOL right;
+
+	BUG_ON (!orig || !new);
+
+	/* First, merge the left and right ends, if necessary. */
+	right = ntfs_rl_merge (new + nsize - 1, orig + loc + 1);
+	if (loc > 0)
+		left = ntfs_rl_merge (orig + loc - 1, new);
+
+	/* Allocate some space.  We'll need less if the left, right
+	 * or both ends were merged. */
+	res = ntfs_rl_realloc (orig, osize, osize + nsize - left - right);
+	if (IS_ERR (res))
+		return res;
+
+	/* Move the tail of Orig out of the way, then copy in New. */
+	rl_mm (res, loc + nsize - left, loc + right + 1,
+		osize - loc - right - 1);
+	rl_mc (res, loc, new, left, nsize - left);
+
+	/* We may have changed the length of the file, so fix the end marker */
+	if (res[loc+nsize-left].lcn == LCN_ENOENT)
+		res[loc+nsize-left].vcn = res[loc+nsize-left-1].vcn +
+					  res[loc+nsize-left-1].length;
+	return res;
+}
+
+/**
+ * ntfs_rl_split - Insert a run_list into the centre of a hole
+ * @orig:   The original run_list to be worked on.
+ * @osize:  The number of elements in @orig (including end marker).
+ * @new:    The run_list to be inserted.
+ * @nsize:  The number of elements in @new (excluding end marker).
+ * @loc:    Index of run_list in @orig to split with @new.
+ *
+ * Split the run_list at @loc into two and insert @new.  No merging of
+ * run_lists is necessary.  Adjust the size of the holes either side.
+ *
+ * It is up to the caller to serialize access to the run lists @orig and @new.
+ *
+ * Return: Pointer, The new, combined, run_list
+ *
+ * Errors: -ENOMEM, Not enough memory to allocate run list array.
+ *         -EINVAL, Invalid parameters were passed in.
+ */
+static inline run_list_element *ntfs_rl_split(run_list_element *orig, int osize,
+		run_list_element *new, int nsize, int loc)
+{
+	run_list_element *res;
+
+	BUG_ON (!orig || !new);
+
+	/* Space required: Orig size + New size + One new hole. */
+	res = ntfs_rl_realloc (orig, osize, osize + nsize + 1);
+	if (IS_ERR (res))
+		return res;
+
+	/* Move the tail of Orig out of the way, then copy in New. */
+	rl_mm (res, loc + 1 + nsize, loc, osize - loc);
+	rl_mc (res, loc + 1, new, 0, nsize);
+
+	/* Adjust the size of the holes either size of New. */
+	res[loc].length         = res[loc+1].vcn       - res[loc].vcn;
+	res[loc+nsize+1].vcn    = res[loc+nsize].vcn   + res[loc+nsize].length;
+	res[loc+nsize+1].length = res[loc+nsize+2].vcn - res[loc+nsize+1].vcn;
+
+	return res;
+}
+
+/**
+ * merge_run_lists - merge two run_lists into one
+ * @drl:  The original run_list.
+ * @srl:  The new run_list to be merge into @drl.
+ *
+ * First we sanity check the two run_lists to make sure that they are sensible
+ * and can be merged.  The @srl run_list must be either after the @drl run_list
+ * or completely within a hole in @drl.
+ *
+ * It is up to the caller to serialize access to the run lists @drl and @srl.
+ *
+ * Merging of run lists is necessary in two cases:
+ *   1. When attribute lists are used and a further extent is being mapped.
+ *   2. When new clusters are allocated to fill a hole or extend a file.
+ *
+ * There are four possible ways @srl can be merged.  It can be inserted at
+ * the beginning of a hole; split the hole in two; appended at the end of
+ * a hole; replace the whole hole.  It can also be appended to the end of
+ * the run_list, which is just a variant of the insert case.
+ *
+ * N.B.  Either, or both, of the input pointers may be freed if the function
+ *       is successful.  Only the returned pointer may be used.
+ *
+ *       If the function fails, neither of the input run_lists may be safe.
+ *
+ * Return: Pointer, The resultant merged run_list.
+ *
+ * Errors: -ENOMEM, Not enough memory to allocate run list array.
+ *         -EINVAL, Invalid parameters were passed in.
+ *         -ERANGE, The run_lists overlap and cannot be merged.
+ */
+run_list_element *merge_run_lists(run_list_element *drl, run_list_element *srl)
+{
+	run_list_element *nrl;	/* New run list. */
+	int di, si;		/* Current index into @[ds]rl. */
+	int sstart;		/* First index with lcn > LCN_RL_NOT_MAPPED. */
+	int dins;		/* Index into @drl at which to insert @srl. */
+	int dend, send;		/* Last index into @[ds]rl. */
+	int dfinal, sfinal;	/* The last index into @[ds]rl with
+				   lcn >= LCN_HOLE. */
+	int marker = 0;
+
+#if 1
+	ntfs_debug ("dst:");
+	ntfs_debug_dump_runlist (drl);
+	ntfs_debug ("src:");
+	ntfs_debug_dump_runlist (srl);
+#endif
+
+ 	/* Check for silly calling... */
+	if (unlikely (!srl))
+		return drl;
+	if (unlikely (IS_ERR (srl) || IS_ERR (drl)))
+		return ERR_PTR (-EINVAL);
+
+	/* Check for the case where the first mapping is being done now. */
+	if (unlikely (!drl)) {
+		nrl = srl;
+
+		/* Complete the source run list if necessary. */
+		if (unlikely (srl[0].vcn)) {
+			/* Scan to the end of the source run list. */
+			for (send = 0; likely (srl[send].length); send++)
+				;
+			nrl = ntfs_rl_realloc (srl, send, send + 1);
+			if (!nrl)
+				return ERR_PTR (-ENOMEM);
+
+			rl_mm (nrl, 1, 0, send);
+			nrl[0].vcn = 0;			/* Add start element. */
+			nrl[0].lcn = LCN_RL_NOT_MAPPED;
+			nrl[0].length = nrl[1].vcn;
+		}
+		goto finished;
+	}
+
+	si = di = 0;
+
+	/* Skip the unmapped start element(s) in each run_list if present. */
+	while (srl[si].length && srl[si].lcn < (LCN)LCN_HOLE)
+		si++;
+
+	/* Can't have an entirely unmapped srl run_list. */
+	BUG_ON (!srl[si].length);
+
+	/* Record the starting points. */
+	sstart = si;
+
+	/*
+	 * Skip forward in @drl until we reach the position where @srl needs to
+	 * be inserted. If we reach the end of @drl, @srl just needs to be
+	 * appended to @drl.
+	 */
+	for (; drl[di].length; di++) {
+		if ((drl[di].vcn + drl[di].length) > srl[sstart].vcn)
+			break;
+	}
+	dins = di;
+
+	/* Sanity check for illegal overlaps. */
+	if ((drl[di].vcn == srl[si].vcn) &&
+	    (drl[di].lcn >= 0) &&
+	    (srl[si].lcn >= 0)) {
+		ntfs_error (NULL, "Run lists overlap. Cannot merge! Returning "
+				"ERANGE.");
+		nrl = ERR_PTR (-ERANGE);
+		goto exit;
+	}
+
+	/* Scan to the end of both run lists in order to know their sizes. */
+	for (send = si; srl[send].length; send++)
+		;
+	for (dend = di; drl[dend].length; dend++)
+		;
+
+	if (srl[send].lcn == LCN_ENOENT) {
+		marker = send;
+	}
+
+	/* Scan to the last element with lcn >= LCN_HOLE. */
+	for (sfinal = send; sfinal >= 0 && srl[sfinal].lcn < LCN_HOLE; sfinal--)
+		;
+	for (dfinal = dend; dfinal >= 0 && drl[dfinal].lcn < LCN_HOLE; dfinal--)
+		;
+
+	{
+	BOOL start;
+	BOOL finish;
+	int ds = dend   + 1;		/* Number of elements in drl & srl */
+	int ss = sfinal - sstart + 1;
+
+	start  = ((drl[dins].lcn <  LCN_RL_NOT_MAPPED) ||    /* End of file   */
+		  (drl[dins].vcn == srl[sstart].vcn));	     /* Start of hole */
+	finish = ((drl[dins].lcn >= LCN_RL_NOT_MAPPED) &&    /* End of file   */
+		 ((drl[dins].vcn + drl[dins].length) <=      /* End of hole   */
+		  (srl[send-1].vcn + srl[send-1].length)));
+		  //srl[send-1].vcn));
+
+	/* Or we'll lose an end marker */
+	if (start && finish && (drl[dins].length == 0))
+		ss++;
+	if (marker && (drl[dins].vcn + drl[dins].length > srl[send-1].vcn))
+		finish = FALSE;
+
+#if 0
+	ntfs_debug("dfinal = %i, dend = %i", dfinal, dend);
+	ntfs_debug("sstart = %i, sfinal = %i, send = %i", sstart, sfinal, send);
+	ntfs_debug("start = %i, finish = %i", start, finish);
+	ntfs_debug("ds = %i, ss = %i, dins = %i", ds, ss, dins);
+#endif
+	if (start)
+		if (finish)
+			nrl = ntfs_rl_replace (drl, ds, srl + sstart, ss, dins);
+		else
+			nrl = ntfs_rl_insert  (drl, ds, srl + sstart, ss, dins);
+	else
+		if (finish)
+			nrl = ntfs_rl_append  (drl, ds, srl + sstart, ss, dins);
+		else
+			nrl = ntfs_rl_split   (drl, ds, srl + sstart, ss, dins);
+
+	if (marker) {
+		for (ds = 0; nrl[ds].lcn; ds++) ;
+		nrl = ntfs_rl_insert (nrl, ds+1, srl + marker, 1, ds-1);
+	}
+	}
+
+	if (likely (!IS_ERR (nrl))) {
+		/* The merge was completed successfully. */
+finished:
+		if (nrl != srl)
+			ntfs_free (srl);
+		/*ntfs_debug ("Done.");*/
+		/*ntfs_debug ("Merged run list:");*/
+
+#if 1
+		ntfs_debug ("res:");
+		ntfs_debug_dump_runlist (nrl);
+#endif
+	} else {
+		ntfs_error (NULL, "Merge failed, returning error code %ld.",
+				-PTR_ERR (nrl));
+	}
+exit:
+	return nrl;
+}
+
+/**
+ * decompress_mapping_pairs - convert mapping pairs array to run list
+ * @vol:	ntfs volume on which the attribute resides
+ * @attr:	attribute record whose mapping pairs array to decompress
+ * @run_list:	optional run list in which to insert @attr's run list
+ *
+ * Decompress the attribute @attr's mapping pairs array into a run_list and
+ * return the run list or -errno on error. If @run_list is not NULL then
+ * the mapping pairs array of @attr is decompressed and the run list inserted
+ * into the appropriate place in @run_list. If this is the case and the
+ * function returns success, the original pointer passed into @run_list is no
+ * longer valid.
+ *
+ * It is up to the caller to serialize access to the run list @old_rl.
+ *
+ * Check the return value for error with IS_ERR(ret_val). If this is FALSE,
+ * the function was successful, the return value is the new run list, and if
+ * an existing run list pointer was passed in, this is no longer valid.
+ * If IS_ERR(ret_val) returns true, there was an error, the return value is not
+ * a run_list pointer and the existing run list pointer if one was passed in
+ * has not been touched. In this case use PTR_ERR(ret_val) to obtain the error
+ * code. Following error codes are defined:
+ * 	-ENOMEM		Not enough memory to allocate run list array.
+ * 	-EIO		Corrupt run list.
+ * 	-EINVAL		Invalid parameters were passed in.
+ * 	-ERANGE		The two run lists overlap.
+ *
+ * FIXME: For now we take the conceptionally simplest approach of creating the
+ * new run list disregarding the already existing one and then splicing the
+ * two into one if that is possible (we check for overlap and discard the new
+ * run list if overlap present and return error).
+ */
+run_list_element *decompress_mapping_pairs(const ntfs_volume *vol,
+		const ATTR_RECORD *attr, run_list_element *old_rl)
+{
+	VCN vcn;		/* Current vcn. */
+	LCN lcn; 		/* Current lcn. */
+	s64 deltaxcn;		/* Change in [vl]cn. */
+	run_list_element *rl = NULL;	/* The output run_list. */
+	run_list_element *rl2;	/* Temporary run_list. */
+	u8 *buf;		/* Current position in mapping pairs array. */
+	u8 *attr_end;		/* End of attribute. */
+	int rlsize;		/* Size of run_list buffer. */
+	int rlpos;		/* Current run_list position. */
+	u8 b;			/* Current byte offset in buf. */
+
+#ifdef DEBUG
+	/* Make sure attr exists and is non-resident. */
+	if (!attr || !attr->non_resident ||
+			sle64_to_cpu(attr->_ANR(lowest_vcn)) < (VCN)0) {
+		ntfs_error(vol->sb, "Invalid arguments.");
+		return ERR_PTR(-EINVAL);
+	}
+#endif
+	/* Start at vcn = lowest_vcn and lcn 0. */
+	vcn = sle64_to_cpu(attr->_ANR(lowest_vcn));
+	lcn = 0;
+	/* Get start of the mapping pairs array. */
+	buf = (u8*)attr + le16_to_cpu(attr->_ANR(mapping_pairs_offset));
+	attr_end = (u8*)attr + le32_to_cpu(attr->length);
+	if (unlikely(buf < (u8*)attr || buf > attr_end)) {
+		ntfs_error(vol->sb, "Corrupt attribute.");
+		return ERR_PTR(-EIO);
+	}
+	/* Current position in run_list array. */
+	rlpos = 0;
+	/* Allocate first page. */
+	rl = ntfs_malloc_nofs(PAGE_SIZE);
+	if (unlikely(!rl))
+		return ERR_PTR(-ENOMEM);
+	/* Current run_list buffer size in bytes. */
+	rlsize = PAGE_SIZE;
+	/* Insert unmapped starting element if necessary. */
+	if (vcn) {
+		rl->vcn = (VCN)0;
+		rl->lcn = (LCN)LCN_RL_NOT_MAPPED;
+		rl->length = vcn;
+		rlpos++;
+	}
+	while (buf < attr_end && *buf) {
+		/*
+		 * Allocate more memory if needed, including space for the
+		 * not-mapped and terminator elements. ntfs_malloc_nofs()
+		 * operates on whole pages only.
+		 */
+		if (((rlpos + 3) * sizeof(*old_rl)) > rlsize) {
+			rl2 = ntfs_malloc_nofs(rlsize + (int)PAGE_SIZE);
+			if (unlikely(!rl2)) {
+				ntfs_free(rl);
+				return ERR_PTR(-ENOMEM);
+			}
+			memmove(rl2, rl, rlsize);
+			ntfs_free(rl);
+			rl = rl2;
+			rlsize += PAGE_SIZE;
+		}
+		/* Enter the current vcn into the current run_list element. */
+		(rl + rlpos)->vcn = vcn;
+		/*
+		 * Get the change in vcn, i.e. the run length in clusters.
+		 * Doing it this way ensures that we signextend negative values.
+		 * A negative run length doesn't make any sense, but hey, I
+		 * didn't make up the NTFS specs and Windows NT4 treats the run
+		 * length as a signed value so that's how it is...
+		 */
+		b = *buf & 0xf;
+		if (b) {
+			if (unlikely(buf + b > attr_end))
+				goto io_error;
+			for (deltaxcn = (s8)buf[b--]; b; b--)
+				deltaxcn = (deltaxcn << 8) + buf[b];
+		} else { /* The length entry is compulsory. */
+			ntfs_error(vol->sb, "Missing length entry in mapping "
+					"pairs array.");
+			deltaxcn = (s64)-1;
+		}
+		/*
+		 * Assume a negative length to indicate data corruption and
+		 * hence clean-up and return NULL.
+		 */
+		if (unlikely(deltaxcn < 0)) {
+			ntfs_error(vol->sb, "Invalid length in mapping pairs "
+					"array.");
+			goto err_out;
+		}
+		/*
+		 * Enter the current run length into the current run_list
+		 * element.
+		 */
+		(rl + rlpos)->length = deltaxcn;
+		/* Increment the current vcn by the current run length. */
+		vcn += deltaxcn;
+		/*
+		 * There might be no lcn change at all, as is the case for
+		 * sparse clusters on NTFS 3.0+, in which case we set the lcn
+		 * to LCN_HOLE.
+		 */
+		if (!(*buf & 0xf0))
+			(rl + rlpos)->lcn = (LCN)LCN_HOLE;
+		else {
+			/* Get the lcn change which really can be negative. */
+			u8 b2 = *buf & 0xf;
+			b = b2 + ((*buf >> 4) & 0xf);
+			if (buf + b > attr_end)
+				goto io_error;
+			for (deltaxcn = (s8)buf[b--]; b > b2; b--)
+				deltaxcn = (deltaxcn << 8) + buf[b];
+			/* Change the current lcn to it's new value. */
+			lcn += deltaxcn;
+#ifdef DEBUG
+			/*
+			 * On NTFS 1.2-, apparently can have lcn == -1 to
+			 * indicate a hole. But we haven't verified ourselves
+			 * whether it is really the lcn or the deltaxcn that is
+			 * -1. So if either is found give us a message so we
+			 * can investigate it further!
+			 */
+			if (vol->major_ver < 3) {
+				if (unlikely(deltaxcn == (LCN)-1))
+					ntfs_error(vol->sb, "lcn delta == -1");
+				if (unlikely(lcn == (LCN)-1))
+					ntfs_error(vol->sb, "lcn == -1");
+			}
+#endif
+			/* Check lcn is not below -1. */
+			if (unlikely(lcn < (LCN)-1)) {
+				ntfs_error(vol->sb, "Invalid LCN < -1 in "
+						"mapping pairs array.");
+				goto err_out;
+			}
+			/* Enter the current lcn into the run_list element. */
+			(rl + rlpos)->lcn = lcn;
+		}
+		/* Get to the next run_list element. */
+		rlpos++;
+		/* Increment the buffer position to the next mapping pair. */
+		buf += (*buf & 0xf) + ((*buf >> 4) & 0xf) + 1;
+	}
+	if (unlikely(buf >= attr_end))
+		goto io_error;
+	/*
+	 * If there is a highest_vcn specified, it must be equal to the final
+	 * vcn in the run list - 1, or something has gone badly wrong.
+	 */
+	deltaxcn = sle64_to_cpu(attr->_ANR(highest_vcn));
+	if (unlikely(deltaxcn && vcn - 1 != deltaxcn)) {
+mpa_err:
+		ntfs_error(vol->sb, "Corrupt mapping pairs array in "
+				"non-resident attribute.");
+		goto err_out;
+	}
+	/* Setup not mapped run_list element if this is the base extent. */
+	if (!attr->_ANR(lowest_vcn)) {
+		VCN max_cluster;
+
+		max_cluster = (sle64_to_cpu(attr->_ANR(allocated_size)) +
+				vol->cluster_size - 1) >>
+				vol->cluster_size_bits;
+		/*
+		 * If there is a difference between the highest_vcn and the
+		 * highest cluster, the run list is either corrupt or, more
+		 * likely, there are more extents following this one.
+		 */
+		if (deltaxcn < --max_cluster) {
+			//RAR ntfs_debug("More extents to follow; deltaxcn = 0x%Lx, "
+					//RAR "max_cluster = 0x%Lx",
+					//RAR (long long)deltaxcn,
+					//RAR (long long)max_cluster);
+			(rl + rlpos)->vcn = vcn;
+			vcn += (rl + rlpos)->length = max_cluster - deltaxcn;
+			(rl + rlpos)->lcn = (LCN)LCN_RL_NOT_MAPPED;
+			rlpos++;
+		} else if (unlikely(deltaxcn > max_cluster)) {
+			ntfs_error(vol->sb, "Corrupt attribute. deltaxcn = "
+					"0x%Lx, max_cluster = 0x%Lx",
+					(long long)deltaxcn,
+					(long long)max_cluster);
+			goto mpa_err;
+		}
+		(rl + rlpos)->lcn = (LCN)LCN_ENOENT;
+	} else /* Not the base extent. There may be more extents to follow. */
+		(rl + rlpos)->lcn = (LCN)LCN_RL_NOT_MAPPED;
+
+	/* Setup terminating run_list element. */
+	(rl + rlpos)->vcn = vcn;
+	(rl + rlpos)->length = (s64)0;
+	//RAR ntfs_debug("Mapping pairs array successfully decompressed.");
+	//RAR ntfs_debug_dump_runlist(rl);
+	/* If no existing run list was specified, we are done. */
+	if (!old_rl)
+		return rl;
+	/* Now combine the new and old run lists checking for overlaps. */
+	rl2 = merge_run_lists(old_rl, rl);
+	if (likely(!IS_ERR(rl2)))
+		return rl2;
+	ntfs_free(rl);
+	ntfs_error(vol->sb, "Failed to merge run lists.");
+	return rl2;
+io_error:
+	ntfs_error(vol->sb, "Corrupt attribute.");
+err_out:
+	ntfs_free(rl);
+	return ERR_PTR(-EIO);
+}
+
+/**
+ * map_run_list - map (a part of) a run list of an ntfs inode
+ * @ni:		ntfs inode for which to map (part of) a run list 
+ * @vcn:	map run list part containing this vcn
+ *
+ * Map the part of a run list containing the @vcn of an the ntfs inode @ni.
+ *
+ * Return 0 on success and -errno on error.
+ */
+int map_run_list(ntfs_inode *ni, VCN vcn)
+{
+	attr_search_context *ctx;
+	MFT_RECORD *mrec;
+	const uchar_t *name;
+	u32 name_len;
+	ATTR_TYPES at;
+	int err;
+	
+	ntfs_debug("Mapping run list part containing vcn 0x%Lx.",
+			(long long)vcn);
+
+	/* Map, pin and lock the mft record for reading. */
+	mrec = map_mft_record(READ, ni);
+	if (IS_ERR(mrec))
+		return PTR_ERR(mrec);
+
+	err = get_attr_search_ctx(&ctx, ni, mrec);
+	if (err)
+		goto unm_err_out;
+
+	/* The attribute type is determined from the inode type. */
+	if (S_ISDIR(VFS_I(ni)->i_mode)) {
+		at = AT_INDEX_ALLOCATION;
+		name = I30;
+		name_len = 4;
+	} else {
+		at = AT_DATA;
+		name = NULL;
+		name_len = 0;
+	}
+
+	/* Find the attribute in the mft record. */
+	if (!lookup_attr(at, name, name_len, CASE_SENSITIVE, vcn, NULL, 0,
+			ctx)) {
+		put_attr_search_ctx(ctx);
+		err = -ENOENT;
+		goto unm_err_out;
+	}
+
+	/* Lock the run list. */
+	write_lock(&ni->run_list.lock);
+
+	/* Make sure someone else didn't do the work while we were spinning. */
+	if (likely(vcn_to_lcn(ni->run_list.rl, vcn) <= LCN_RL_NOT_MAPPED)) {
+		run_list_element *rl;
+
+		/* Decode the run list. */
+		rl = decompress_mapping_pairs(ni->vol, ctx->attr,
+				ni->run_list.rl);
+
+		/* Flag any errors or set the run list if successful. */
+		if (unlikely(IS_ERR(rl)))
+			err = PTR_ERR(rl);
+		else
+			ni->run_list.rl = rl;
+	}
+
+	/* Unlock the run list. */
+	write_unlock(&ni->run_list.lock);
+	
+	put_attr_search_ctx(ctx);
+
+	/* Unlock, unpin and release the mft record. */
+	unmap_mft_record(READ, ni);
+
+	/* If an error occured, return it. */
+	ntfs_debug("Done.");
+	return err;
+
+unm_err_out:
+	unmap_mft_record(READ, ni);
+	return err;
+}
+
+/**
+ * vcn_to_lcn - convert a vcn into a lcn given a run list
+ * @rl:		run list to use for conversion
+ * @vcn:	vcn to convert
+ *
+ * Convert the virtual cluster number @vcn of an attribute into a logical
+ * cluster number (lcn) of a device using the run list @rl to map vcns to their
+ * corresponding lcns.
+ *
+ * It is up to the caller to serialize access to the run list @rl.
+ *
+ * Since lcns must be >= 0, we use negative return values with special meaning:
+ *
+ * Return value			Meaning / Description
+ * ==================================================
+ *  -1 = LCN_HOLE		Hole / not allocated on disk.
+ *  -2 = LCN_RL_NOT_MAPPED	This is part of the run list which has not been
+ *				inserted into the run list yet.
+ *  -3 = LCN_ENOENT		There is no such vcn in the data attribute.
+ *  -4 = LCN_EINVAL		Input parameter error (if debug enabled).
+ */
+LCN vcn_to_lcn(const run_list_element *rl, const VCN vcn)
+{
+	int i;
+
+#ifdef DEBUG
+	if (vcn < (VCN)0)
+		return (LCN)LCN_EINVAL;
+#endif
+	/*
+	 * If rl is NULL, assume that we have found an unmapped run list. The
+	 * caller can then attempt to map it and fail appropriately if
+	 * necessary.
+	 */
+	if (unlikely(!rl))
+		return (LCN)LCN_RL_NOT_MAPPED;
+
+	/* Catch out of lower bounds vcn. */
+	if (unlikely(vcn < rl[0].vcn))
+		return (LCN)LCN_ENOENT;
+
+	for (i = 0; likely(rl[i].length); i++) {
+		if (unlikely(vcn < rl[i+1].vcn)) {
+			if (likely(rl[i].lcn >= (LCN)0))
+				return rl[i].lcn + (vcn - rl[i].vcn);
+			return rl[i].lcn;
+		}
+	}
+	/*
+	 * The terminator element is setup to the correct value, i.e. one of
+	 * LCN_HOLE, LCN_RL_NOT_MAPPED, or LCN_ENOENT.
+	 */
+	if (likely(rl[i].lcn < (LCN)0))
+		return rl[i].lcn;
+	/* Just in case... We could replace this with BUG() some day. */
+	return (LCN)LCN_ENOENT;
+}
+
+/**
+ * find_attr - find (next) attribute in mft record
+ * @type:	attribute type to find
+ * @name:	attribute name to find (optional, i.e. NULL means don't care)
+ * @name_len:	attribute name length (only needed if @name present)
+ * @ic:		IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
+ * @val:	attribute value to find (optional, resident attributes only)
+ * @val_len:	attribute value length
+ * @ctx:	search context with mft record and attribute to search from
+ *
+ * You shouldn't need to call this function directly. Use lookup_attr() instead.
+ *
+ * find_attr() takes a search context @ctx as parameter and searches the mft
+ * record specified by @ctx->mrec, beginning at @ctx->attr, for an attribute of
+ * @type, optionally @name and @val. If found, find_attr() returns TRUE and
+ * @ctx->attr will point to the found attribute. If not found, find_attr()
+ * returns FALSE and @ctx->attr is undefined (i.e. do not rely on it not
+ * changing).
+ *
+ * If @ctx->is_first is TRUE, the search begins with @ctx->attr itself. If it
+ * is FALSE, the search begins after @ctx->attr.
+ *
+ * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and
+ * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record
+ * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at
+ * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case
+ * sensitive. When @name is present, @name_len is the @name length in Unicode
+ * characters.
+ *
+ * If @name is not present (NULL), we assume that the unnamed attribute is
+ * being searched for.
+ *
+ * Finally, the resident attribute value @val is looked for, if present. If @val
+ * is not present (NULL), @val_len is ignored.
+ *
+ * find_attr() only searches the specified mft record and it ignores the
+ * presence of an attribute list attribute (unless it is the one being searched
+ * for, obviously). If you need to take attribute lists into consideration, use
+ * lookup_attr() instead (see below). This also means that you cannot use
+ * find_attr() to search for extent records of non-resident attributes, as
+ * extents with lowest_vcn != 0 are usually described by the attribute list
+ * attribute only. - Note that it is possible that the first extent is only in
+ * the attribute list while the last extent is in the base mft record, so don't
+ * rely on being able to find the first extent in the base mft record.
+ *
+ * Warning: Never use @val when looking for attribute types which can be
+ *	    non-resident as this most likely will result in a crash!
+ */
+BOOL find_attr(const ATTR_TYPES type, const uchar_t *name, const u32 name_len,
+		const IGNORE_CASE_BOOL ic, const u8 *val, const u32 val_len,
+		attr_search_context *ctx)
+{
+	ATTR_RECORD *a;
+	ntfs_volume *vol;
+	uchar_t *upcase;
+	u32 upcase_len;
+
+	if (ic == IGNORE_CASE) {
+		vol = ctx->ntfs_ino->vol;
+		upcase = vol->upcase;
+		upcase_len = vol->upcase_len;
+	} else {
+		vol = NULL;
+		upcase = NULL;
+		upcase_len = 0;
+	}
+	/*
+	 * Iterate over attributes in mft record starting at @ctx->attr, or the
+	 * attribute following that, if @ctx->is_first is TRUE.
+	 */
+	if (ctx->is_first) {
+		a = ctx->attr;
+		ctx->is_first = FALSE;
+	} else
+		a = (ATTR_RECORD*)((u8*)ctx->attr +
+				le32_to_cpu(ctx->attr->length));
+	for (;;	a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length))) {
+		if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
+				le32_to_cpu(ctx->mrec->bytes_allocated))
+			break;
+		ctx->attr = a;
+		/* We catch $END with this more general check, too... */
+		if (le32_to_cpu(a->type) > le32_to_cpu(type))
+			return FALSE;
+		if (unlikely(!a->length))
+			break;
+		if (a->type != type)
+			continue;
+		/* 
+		 * If @name is present, compare the two names. If @name is
+		 * missing, assume we want an unnamed attribute.
+		 */
+		if (!name) {
+			/* The search failed if the found attribute is named. */
+			if (a->name_length)
+				return FALSE;
+		} else if (!ntfs_are_names_equal(name, name_len,
+			    (uchar_t*)((u8*)a + le16_to_cpu(a->name_offset)),
+			    a->name_length, ic, upcase, upcase_len)) {
+			register int rc;
+			
+			rc = ntfs_collate_names(name, name_len,
+					(uchar_t*)((u8*)a +
+						le16_to_cpu(a->name_offset)),
+					a->name_length, 1, IGNORE_CASE,
+					upcase, upcase_len);
+			/*
+			 * If @name collates before a->name, there is no
+			 * matching attribute.
+			 */
+			if (rc == -1)
+				return FALSE;
+			/* If the strings are not equal, continue search. */
+			if (rc)
+	 			continue;
+			rc = ntfs_collate_names(name, name_len,
+					(uchar_t*)((u8*)a +
+						le16_to_cpu(a->name_offset)),
+					a->name_length, 1, CASE_SENSITIVE,
+					upcase, upcase_len);
+			if (rc == -1)
+				return FALSE;
+			if (rc)
+				continue;
+		}
+		/*
+		 * The names match or @name not present and attribute is
+		 * unnamed. If no @val specified, we have found the attribute
+		 * and are done.
+		 */
+		if (!val)
+			return TRUE;
+		/* @val is present; compare values. */
+		else {
+			register int rc;
+			
+			rc = memcmp(val, (u8*)a +le16_to_cpu(a->_ARA(value_offset)),
+				min(val_len, le32_to_cpu(a->_ARA(value_length))));
+			/*
+			 * If @val collates before the current attribute's
+			 * value, there is no matching attribute.
+			 */
+			if (!rc) {
+				register u32 avl;
+				avl = le32_to_cpu(a->_ARA(value_length));
+				if (val_len == avl)
+					return TRUE;
+				if (val_len < avl)
+					return FALSE;
+			} else if (rc < 0)
+				return FALSE;
+		}
+	}
+	ntfs_error(NULL, "Inode is corrupt. Run chkdsk.");
+	return FALSE;
+}
+
+/**
+ * load_attribute_list - load an attribute list into memory
+ * @vol:	ntfs volume from which to read
+ * @rl:		run list of the attribute list
+ * @al:		destination buffer
+ * @size:	size of the destination buffer in bytes
+ *
+ * Walk the run list @rl and load all clusters from it copying them into the
+ * linear buffer @al. The maximum number of bytes copied to @al is @size bytes.
+ * Note, @size does not need to be a multiple of the cluster size.
+ *
+ * It is up to the caller to serialize access to the run list @rl.
+ *
+ * Return 0 on success or -errno on error.
+ */
+int load_attribute_list(ntfs_volume *vol, run_list_element *rl, u8 *al,
+		const s64 size)
+{
+	LCN lcn;
+	u8 *al_end = al + size;
+	struct buffer_head *bh;
+	struct super_block *sb = vol->sb;
+	unsigned long block_size = sb->s_blocksize;
+	unsigned long block, max_block;
+	unsigned char block_size_bits = sb->s_blocksize_bits;
+
+	ntfs_debug("Entering.");
+#ifdef DEBUG
+	if (!vol || !rl || !al || size <= 0)
+		return -EINVAL;
+#endif
+	/* Read all clusters specified by the run list one run at a time. */
+	while (rl->length) {
+		lcn = vcn_to_lcn(rl, rl->vcn);
+		ntfs_debug("Reading vcn = 0x%Lx, lcn = 0x%Lx.",
+				(long long)rl->vcn, (long long)lcn);
+		/* The attribute list cannot be sparse. */
+		if (lcn < 0) {
+			ntfs_error(sb, "vcn_to_lcn() failed. Cannot read "
+					"attribute list.");
+			return -EIO;;
+		}
+		block = lcn << vol->cluster_size_bits >> block_size_bits;
+		/* Read the run from device in chunks of block_size bytes. */
+		max_block = block + (rl->length << vol->cluster_size_bits >>
+				block_size_bits);
+		ntfs_debug("max_block = 0x%lx.", max_block);
+		do {
+			ntfs_debug("Reading block = 0x%lx.", block);
+			bh = sb_bread(sb, block);
+			if (!bh)
+				goto bread_err;
+			if (al + block_size > al_end)
+				goto do_partial;
+			memcpy(al, bh->b_data, block_size);
+			brelse(bh);
+			al += block_size;
+		} while (++block < max_block);
+		rl++;
+	}
+	return 0;
+do_partial:
+	if (al < al_end) {
+		/* Partial block. */
+		memcpy(al, bh->b_data, al_end - al);
+		brelse(bh);
+		/* If the final lcn is partial all is fine. */
+		if (((s64)(block - (lcn << vol->cluster_size_bits >>
+				block_size_bits)) << block_size_bits >>
+				vol->cluster_size_bits) == rl->length - 1) {
+			if (!(rl + 1)->length)
+				return 0;
+			if ((rl + 1)->lcn == LCN_RL_NOT_MAPPED &&
+					!(rl + 2)->length)
+				return 0;
+		}
+	} else
+		brelse(bh);
+	/* Real overflow! */
+	ntfs_error(sb, "Attribute list buffer overflow. Read attribute list "
+			"is truncated.");
+err_out:
+	return -EIO;
+bread_err:
+	ntfs_error(sb, "sb_bread() failed. Cannot read attribute list.");
+	goto err_out;
+}
+
+/**
+ * find_external_attr - find an attribute in the attribute list of an ntfs inode
+ * @type:	attribute type to find
+ * @name:	attribute name to find (optional, i.e. NULL means don't care)
+ * @name_len:	attribute name length (only needed if @name present)
+ * @ic:		IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
+ * @lowest_vcn:	lowest vcn to find (optional, non-resident attributes only)
+ * @val:	attribute value to find (optional, resident attributes only)
+ * @val_len:	attribute value length
+ * @ctx:	search context with mft record and attribute to search from
+ *
+ * You shouldn't need to call this function directly. Use lookup_attr() instead.
+ *
+ * Find an attribute by searching the attribute list for the corresponding
+ * attribute list entry. Having found the entry, map the mft record for read
+ * if the attribute is in a different mft record/inode, find_attr the attribute
+ * in there and return it.
+ *
+ * On first search @ctx->ntfs_ino must be the base mft record and @ctx must
+ * have been obtained from a call to get_attr_search_ctx(). On subsequent calls
+ * @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is then the
+ * base inode).
+ *
+ * After finishing with the attribute/mft record you need to call
+ * release_attr_search_ctx() to cleanup the search context (unmapping any
+ * mapped inodes, etc).
+ *
+ * Return TRUE if the search was successful and FALSE if not. When TRUE,
+ * @ctx->attr is the found attribute and it is in mft record @ctx->mrec. When
+ * FALSE, @ctx->attr is the attribute which collates just after the attribute
+ * being searched for in the base ntfs inode, i.e. if one wants to add the
+ * attribute to the mft record this is the correct place to insert it into
+ * and if there is not enough space, the attribute should be placed in an
+ * extent mft record.
+ */
+static BOOL find_external_attr(const ATTR_TYPES type, const uchar_t *name,
+		const u32 name_len, const IGNORE_CASE_BOOL ic,
+		const VCN lowest_vcn, const u8 *val, const u32 val_len,
+		attr_search_context *ctx)
+{
+	ntfs_inode *base_ni, *ni;
+	ntfs_volume *vol;
+	ATTR_LIST_ENTRY *al_entry, *next_al_entry;
+	u8 *al_start, *al_end;
+	ATTR_RECORD *a;
+	uchar_t *al_name;
+	u32 al_name_len;
+
+	ni = ctx->ntfs_ino;
+	base_ni = ctx->base_ntfs_ino;
+	ntfs_debug("Entering for inode 0x%Lx, type 0x%x.",
+			(unsigned long long)ni->mft_no, type);
+	if (!base_ni) {
+		/* First call happens with the base mft record. */
+		base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino;
+		ctx->base_mrec = ctx->mrec;
+	}
+	if (ni == base_ni)
+		ctx->base_attr = ctx->attr;
+	vol = base_ni->vol;
+	al_start = base_ni->attr_list;
+	al_end = al_start + base_ni->attr_list_size;
+	if (!ctx->al_entry)
+		ctx->al_entry = (ATTR_LIST_ENTRY*)al_start;
+	/*
+	 * Iterate over entries in attribute list starting at @ctx->al_entry,
+	 * or the entry following that, if @ctx->is_first is TRUE.
+	 */
+	if (ctx->is_first) {
+		al_entry = ctx->al_entry;
+		ctx->is_first = FALSE;
+	} else
+		al_entry = (ATTR_LIST_ENTRY*)((u8*)ctx->al_entry +
+				le16_to_cpu(ctx->al_entry->length));
+	for (;; al_entry = next_al_entry) {
+		/* Out of bounds check. */
+		if ((u8*)al_entry < base_ni->attr_list ||
+				(u8*)al_entry > al_end)
+			break;	/* Inode is corrupt. */
+		ctx->al_entry = al_entry;
+		/* Catch the end of the attribute list. */
+		if ((u8*)al_entry == al_end)
+			goto not_found;
+		if (!al_entry->length)
+			break;
+		if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
+				le16_to_cpu(al_entry->length) > al_end)
+			break;
+		next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
+				le16_to_cpu(al_entry->length));
+		if (le32_to_cpu(al_entry->type) > le32_to_cpu(type))
+			goto not_found;
+		if (type != al_entry->type)
+			continue;
+		/*
+		 * If @name is present, compare the two names. If @name is
+		 * missing, assume we want an unnamed attribute.
+		 */
+		al_name_len = al_entry->name_length;
+		al_name = (uchar_t*)((u8*)al_entry + al_entry->name_offset);
+		if (!name) {
+			if (al_name_len)
+				goto not_found;
+		} else if (!ntfs_are_names_equal(al_name, al_name_len, name,
+				name_len, ic, vol->upcase, vol->upcase_len)) {
+			register int rc;
+
+			rc = ntfs_collate_names(name, name_len, al_name,
+					al_name_len, 1, IGNORE_CASE,
+					vol->upcase, vol->upcase_len);
+			/*
+			 * If @name collates before al_name, there is no
+			 * matching attribute.
+			 */
+			if (rc == -1)
+				goto not_found;
+			/* If the strings are not equal, continue search. */
+			if (rc)
+				continue;
+			/*
+			 * FIXME: Reverse engineering showed 0, IGNORE_CASE but
+			 * that is inconsistent with find_attr(). The subsequent
+			 * rc checks were also different. Perhaps I made a
+			 * mistake in one of the two. Need to recheck which is
+			 * correct or at least see what is going on... (AIA)
+			 */
+			rc = ntfs_collate_names(name, name_len, al_name,
+					al_name_len, 1, CASE_SENSITIVE,
+					vol->upcase, vol->upcase_len);
+			if (rc == -1)
+				goto not_found;
+			if (rc)
+				continue;
+		}
+		/*
+		 * The names match or @name not present and attribute is
+		 * unnamed. Now check @lowest_vcn. Continue search if the
+		 * next attribute list entry still fits @lowest_vcn. Otherwise
+		 * we have reached the right one or the search has failed.
+		 */
+		if (lowest_vcn && (u8*)next_al_entry >= al_start	    &&
+				(u8*)next_al_entry + 6 < al_end		    &&
+				(u8*)next_al_entry + le16_to_cpu(
+					next_al_entry->length) <= al_end    &&	
+				sle64_to_cpu(next_al_entry->lowest_vcn) <=
+					sle64_to_cpu(lowest_vcn)	    &&
+				next_al_entry->type == al_entry->type	    &&
+				next_al_entry->name_length == al_name_len   &&
+				ntfs_are_names_equal((uchar_t*)((u8*)
+					next_al_entry +
+					next_al_entry->name_offset),
+					next_al_entry->name_length,
+					al_name, al_name_len, CASE_SENSITIVE,
+					vol->upcase, vol->upcase_len))
+			continue;
+		if (MREF_LE(al_entry->mft_reference) == ni->mft_no) {
+			if (MSEQNO_LE(al_entry->mft_reference) != ni->seq_no) {
+				ntfs_error(vol->sb, "Found stale mft "
+						"reference in attribute list!");
+				break;
+			}
+		} else { /* Mft references do not match. */
+			/* If there is a mapped record unmap it first. */
+			if (ni != base_ni)
+				unmap_extent_mft_record(ni);
+			/* Do we want the base record back? */
+			if (MREF_LE(al_entry->mft_reference) ==
+					base_ni->mft_no) {
+				ni = ctx->ntfs_ino = base_ni;
+				ctx->mrec = ctx->base_mrec;
+			} else {
+				/* We want an extent record. */
+				ctx->mrec = map_extent_mft_record(base_ni,
+						al_entry->mft_reference, &ni);
+				ctx->ntfs_ino = ni;
+				if (IS_ERR(ctx->mrec)) {
+					ntfs_error(vol->sb, "Failed to map mft "
+							"record, error code "
+							"%ld.",
+							-PTR_ERR(ctx->mrec));
+					break;
+				}
+			}
+			ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
+					le16_to_cpu(ctx->mrec->attrs_offset));
+		}
+		/*
+		 * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the
+		 * mft record containing the attribute represented by the
+		 * current al_entry.
+		 */
+		/*
+		 * We could call into find_attr() to find the right attribute
+		 * in this mft record but this would be less efficient and not
+		 * quite accurate as find_attr() ignores the attribute instance
+		 * numbers for example which become important when one plays
+		 * with attribute lists. Also, because a proper match has been
+		 * found in the attribute list entry above, the comparison can
+		 * now be optimized. So it is worth re-implementing a
+		 * simplified find_attr() here.
+		 */
+		a = ctx->attr;
+		/*
+		 * Use a manual loop so we can still use break and continue
+		 * with the same meanings as above.
+		 */
+do_next_attr_loop:
+		if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
+				le32_to_cpu(ctx->mrec->bytes_allocated))
+			break;
+		if (a->type == AT_END)
+			continue;
+		if (!a->length)
+			break;
+		if (al_entry->instance != a->instance)
+			goto do_next_attr;
+		if (al_entry->type != a->type)
+			continue;
+		if (name) {
+			if (a->name_length != al_name_len)
+				continue;
+			if (!ntfs_are_names_equal((uchar_t*)((u8*)a +
+					le16_to_cpu(a->name_offset)),
+					a->name_length, al_name, al_name_len,
+					CASE_SENSITIVE, vol->upcase,
+					vol->upcase_len))
+				continue;
+		}
+		ctx->attr = a;
+		/*
+		 * If no @val specified or @val specified and it matches, we
+		 * have found it!
+		 */
+		if (!val || (!a->non_resident && le32_to_cpu(a->_ARA(value_length))
+				== val_len && !memcmp((u8*)a +
+				le16_to_cpu(a->_ARA(value_offset)), val, val_len))) {
+			ntfs_debug("Done, found.");
+			return TRUE;
+		}
+do_next_attr:
+		/* Proceed to the next attribute in the current mft record. */
+		a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length));
+		goto do_next_attr_loop;
+	}
+	ntfs_error(base_ni->vol->sb, "Inode contains corrupt attribute list "
+			"attribute.\n");
+	if (ni != base_ni) {
+		unmap_extent_mft_record(ni);
+		ctx->ntfs_ino = base_ni;
+		ctx->mrec = ctx->base_mrec;
+		ctx->attr = ctx->base_attr;
+	}
+	/*
+	 * FIXME: We absolutely have to return ERROR status instead of just
+	 * false or we will blow up or even worse cause corruption when we add
+	 * write support and we reach this code path!
+	 */
+	printk(KERN_CRIT "NTFS: FIXME: Hit unfinished error code path!!!\n");
+	return FALSE;
+not_found:
+	/*
+	 * Seek to the end of the base mft record, i.e. when we return false,
+	 * ctx->mrec and ctx->attr indicate where the attribute should be
+	 * inserted into the attribute record.
+	 * And of course ctx->al_entry points to the end of the attribute
+	 * list inside NTFS_I(ctx->base_vfs_ino)->attr_list.
+	 *
+	 * FIXME: Do we really want to do this here? Think about it... (AIA)
+	 */
+	reinit_attr_search_ctx(ctx);
+	find_attr(type, name, name_len, ic, val, val_len, ctx);
+	ntfs_debug("Done, not found.");
+	return FALSE;
+}
+
+/**
+ * lookup_attr - find an attribute in an ntfs inode
+ * @type:	attribute type to find
+ * @name:	attribute name to find (optional, i.e. NULL means don't care)
+ * @name_len:	attribute name length (only needed if @name present)
+ * @ic:		IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
+ * @lowest_vcn:	lowest vcn to find (optional, non-resident attributes only)
+ * @val:	attribute value to find (optional, resident attributes only)
+ * @val_len:	attribute value length
+ * @ctx:	search context with mft record and attribute to search from
+ *
+ * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must
+ * be the base mft record and @ctx must have been obtained from a call to
+ * get_attr_search_ctx().
+ *
+ * This function transparently handles attribute lists and @ctx is used to
+ * continue searches where they were left off at.
+ *
+ * After finishing with the attribute/mft record you need to call
+ * release_attr_search_ctx() to cleanup the search context (unmapping any
+ * mapped inodes, etc).
+ *
+ * Return TRUE if the search was successful and FALSE if not. When TRUE,
+ * @ctx->attr is the found attribute and it is in mft record @ctx->mrec. When
+ * FALSE, @ctx->attr is the attribute which collates just after the attribute
+ * being searched for, i.e. if one wants to add the attribute to the mft
+ * record this is the correct place to insert it into.
+ */
+BOOL lookup_attr(const ATTR_TYPES type, const uchar_t *name, const u32 name_len,
+		const IGNORE_CASE_BOOL ic, const VCN lowest_vcn, const u8 *val,
+		const u32 val_len, attr_search_context *ctx)
+{
+	ntfs_inode *base_ni;
+
+	ntfs_debug("Entering.");
+	if (ctx->base_ntfs_ino)
+		base_ni = ctx->base_ntfs_ino;
+	else
+		base_ni = ctx->ntfs_ino;
+	/* Sanity check, just for debugging really. */
+	BUG_ON(!base_ni);
+	if (!NInoAttrList(base_ni))
+		return find_attr(type, name, name_len, ic, val, val_len, ctx);
+	return find_external_attr(type, name, name_len, ic, lowest_vcn, val,
+			val_len, ctx);
+}
+
+/**
+ * init_attr_search_ctx - initialize an attribute search context
+ * @ctx:	attribute search context to initialize
+ * @ni:		ntfs inode with which to initialize the search context
+ * @mrec:	mft record with which to initialize the search context
+ *
+ * Initialize the attribute search context @ctx with @ni and @mrec.
+ */
+static inline void init_attr_search_ctx(attr_search_context *ctx,
+		ntfs_inode *ni, MFT_RECORD *mrec)
+{
+	ctx->mrec = mrec;
+	/* Sanity checks are performed elsewhere. */
+	ctx->attr = (ATTR_RECORD*)((u8*)mrec + le16_to_cpu(mrec->attrs_offset));
+	ctx->is_first = TRUE;
+	ctx->ntfs_ino = ni;
+	ctx->al_entry = NULL;
+	ctx->base_ntfs_ino = NULL;
+	ctx->base_mrec = NULL;
+	ctx->base_attr = NULL;
+}
+
+/**
+ * reinit_attr_search_ctx - reinitialize an attribute search context
+ * @ctx:	attribute search context to reinitialize
+ *
+ * Reinitialize the attribute search context @ctx, unmapping an associated
+ * extent mft record if present, and initialize the search context again.
+ *
+ * This is used when a search for a new attribute is being started to reset
+ * the search context to the beginning.
+ */
+void reinit_attr_search_ctx(attr_search_context *ctx)
+{
+	if (likely(!ctx->base_ntfs_ino)) {
+		/* No attribute list. */
+		ctx->is_first = TRUE;
+		/* Sanity checks are performed elsewhere. */
+		ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
+				le16_to_cpu(ctx->mrec->attrs_offset));
+		return;
+	} /* Attribute list. */
+	if (ctx->ntfs_ino != ctx->base_ntfs_ino)
+		unmap_mft_record(READ, ctx->ntfs_ino);
+	init_attr_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec);
+	return;
+}
+
+/**
+ * get_attr_search_ctx - allocate and initialize a new attribute search context
+ * @ctx:	address of pointer in which to return the new search context
+ * @ni:		ntfs inode with which to initialize the search context
+ * @mrec:	mft record with which to initialize the search context
+ *
+ * Allocate a new attribute search context, initialize it with @ni and @mrec,
+ * and return it in *@ctx. Return 0 on success or -ENOMEM if allocation failed.
+ */
+int get_attr_search_ctx(attr_search_context **ctx, ntfs_inode *ni,
+		MFT_RECORD *mrec)
+{
+	*ctx = kmem_cache_alloc(ntfs_attr_ctx_cache, SLAB_NOFS);
+	if (unlikely(!*ctx))
+		return -ENOMEM;
+	init_attr_search_ctx(*ctx, ni, mrec);
+	return 0;
+}
+
+/**
+ * put_attr_search_ctx - release an attribute search context
+ * @ctx:	attribute search context to free
+ *
+ * Release the attribute search context @ctx, unmapping an associated extent
+ * mft record if prseent.
+ */
+void put_attr_search_ctx(attr_search_context *ctx)
+{
+	if (ctx->base_ntfs_ino && ctx->ntfs_ino != ctx->base_ntfs_ino)
+		unmap_mft_record(READ, ctx->ntfs_ino);
+	kmem_cache_free(ntfs_attr_ctx_cache, ctx);
+	return;
+}
+

fs/ntfs/attrib.h

+/*
+ * attrib.h - Defines for attribute handling in NTFS Linux kernel driver.
+ *	      Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_ATTRIB_H
+#define _LINUX_NTFS_ATTRIB_H
+
+#include <linux/fs.h>
+
+#include "endian.h"
+#include "types.h"
+#include "layout.h"
+
+typedef enum {
+	LCN_HOLE		= -1,	/* Keep this as highest value or die! */
+	LCN_RL_NOT_MAPPED	= -2,
+	LCN_ENOENT		= -3,
+	LCN_EINVAL		= -4,
+} LCN_SPECIAL_VALUES;
+
+/**
+ * attr_search_context - used in attribute search functions
+ * @mrec:	buffer containing mft record to search
+ * @attr:	attribute record in @mrec where to begin/continue search
+ * @is_first:	if true lookup_attr() begins search with @attr, else after @attr
+ *
+ * Structure must be initialized to zero before the first call to one of the
+ * attribute search functions. Initialize @mrec to point to the mft record to
+ * search, and @attr to point to the first attribute within @mrec (not necessary
+ * if calling the _first() functions), and set @is_first to TRUE (not necessary
+ * if calling the _first() functions).
+ *
+ * If @is_first is TRUE, the search begins with @attr. If @is_first is FALSE,
+ * the search begins after @attr. This is so that, after the first call to one
+ * of the search attribute functions, we can call the function again, without
+ * any modification of the search context, to automagically get the next
+ * matching attribute.
+ */
+typedef struct {
+	MFT_RECORD *mrec;
+	ATTR_RECORD *attr;
+	BOOL is_first;
+	ntfs_inode *ntfs_ino;
+	ATTR_LIST_ENTRY *al_entry;
+	ntfs_inode *base_ntfs_ino;
+	MFT_RECORD *base_mrec;
+	ATTR_RECORD *base_attr;
+} attr_search_context;
+
+extern run_list_element *decompress_mapping_pairs(const ntfs_volume *vol,
+		const ATTR_RECORD *attr, run_list_element *old_rl);
+
+extern int map_run_list(ntfs_inode *ni, VCN vcn);
+
+extern LCN vcn_to_lcn(const run_list_element *rl, const VCN vcn);
+
+extern BOOL find_attr(const ATTR_TYPES type, const uchar_t *name,
+		const u32 name_len, const IGNORE_CASE_BOOL ic, const u8 *val,
+		const u32 val_len, attr_search_context *ctx);
+
+BOOL lookup_attr(const ATTR_TYPES type, const uchar_t *name, const u32 name_len,
+		const IGNORE_CASE_BOOL ic, const VCN lowest_vcn, const u8 *val,
+		const u32 val_len, attr_search_context *ctx);
+
+extern int load_attribute_list(ntfs_volume *vol, run_list_element *rl, u8 *al,
+		const s64 size);
+
+static inline s64 attribute_value_length(const ATTR_RECORD *a)
+{
+	if (!a->non_resident)
+		return (s64)le32_to_cpu(a->_ARA(value_length));
+	return sle64_to_cpu(a->_ANR(data_size));
+}
+
+extern void reinit_attr_search_ctx(attr_search_context *ctx);
+extern int get_attr_search_ctx(attr_search_context **ctx, ntfs_inode *ni,
+		MFT_RECORD *mrec);
+extern void put_attr_search_ctx(attr_search_context *ctx);
+
+#endif /* _LINUX_NTFS_ATTRIB_H */
+

fs/ntfs/compress.c

+/**
+ * compress.c - NTFS kernel compressed attributes handling.
+ *		Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/locks.h>
+#include <linux/fs.h>
+
+#include "ntfs.h"
+
+/**
+ * ntfs_compression_constants - enum of constants used in the compression code
+ */
+typedef enum {
+	/* Token types and access mask. */
+	NTFS_SYMBOL_TOKEN	=	0,
+	NTFS_PHRASE_TOKEN	=	1,
+	NTFS_TOKEN_MASK		=	1,
+
+	/* Compression sub-block constants. */
+	NTFS_SB_SIZE_MASK	=	0x0fff,
+	NTFS_SB_SIZE		=	0x1000,
+	NTFS_SB_IS_COMPRESSED	=	0x8000,
+
+	/*
+	 * The maximum compression block size is by definition 16 * the cluster
+	 * size, with the maximum supported cluster size being 4kiB. Thus the
+	 * maximum compression buffer size is 64kiB, so we use this when
+	 * initializing the per-CPU buffers.
+	 */
+	NTFS_MAX_CB_SIZE	= 64 * 1024,
+} ntfs_compression_constants;
+
+/**
+ * ntfs_compression_buffers - per-CPU buffers for the decompression engine.
+ */
+static u8 **ntfs_compression_buffers = NULL;
+
+/**
+ * allocate_compression_buffers - allocate the per-CPU decompression buffers
+ *
+ * Allocate the per-CPU buffers for the decompression engine.
+ *
+ * Caller has to hold the ntfs_lock semaphore.
+ *
+ * Return 0 on success or -ENOMEM if the allocations failed.
+ */
+int allocate_compression_buffers(void)
+{
+	int i, j;
+
+	BUG_ON(ntfs_compression_buffers);
+
+	ntfs_compression_buffers =  (u8**)kmalloc(smp_num_cpus * sizeof(u8 *),
+			GFP_KERNEL);
+	if (!ntfs_compression_buffers)
+		return -ENOMEM;
+	for (i = 0; i < smp_num_cpus; i++) {
+		ntfs_compression_buffers[i] = (u8*)vmalloc(NTFS_MAX_CB_SIZE);
+		if (!ntfs_compression_buffers[i])
+			break;
+	}
+	if (i == smp_num_cpus)
+		return 0;
+	/* Allocation failed, cleanup and return error. */
+	for (j = 0; i < j; j++)
+		vfree(ntfs_compression_buffers[j]);
+	kfree(ntfs_compression_buffers);
+	return -ENOMEM;
+}
+
+/**
+ * free_compression_buffers - free the per-CPU decompression buffers
+ *
+ * Free the per-CPU buffers used by the decompression engine.
+ *
+ * Caller has to hold the ntfs_lock semaphore.
+ */
+void free_compression_buffers(void)
+{
+	int i;
+
+	BUG_ON(!ntfs_compression_buffers);
+
+	for (i = 0; i < smp_num_cpus; i++)
+		vfree(ntfs_compression_buffers[i]);
+	kfree(ntfs_compression_buffers);
+	ntfs_compression_buffers = NULL;
+}
+
+/**
+ * ntfs_decompress - decompress a compression block into an array of pages
+ * @dest_pages:		destination array of pages
+ * @dest_index:		current index into @dest_pages (IN/OUT)
+ * @dest_ofs:		current offset within @dest_pages[@dest_index] (IN/OUT)
+ * @dest_max_index:	maximum index into @dest_pages (IN)
+ * @dest_max_ofs:	maximum offset within @dest_pages[@dest_max_index] (IN)
+ * @xpage:		the target page (-1 if none) (IN)
+ * @xpage_done:		set to 1 if xpage was completed successfully (IN/OUT)
+ * @cb_start:		compression block to decompress (IN)
+ * @cb_size:		size of compression block @cb_start in bytes (IN)
+ *
+ * The caller must have disabled preemption. ntfs_decompress() reenables it when
+ * the critical section is finished.
+ *
+ * This decompresses the compression block @cb_start into the array of
+ * destination pages @dest_pages starting at index @dest_index into @dest_pages
+ * and at offset @dest_pos into the page @dest_pages[@dest_index].
+ *
+ * When the page @dest_pages[@xpage] is completed, @xpage_done is set to 1.
+ * If xpage is -1 or @xpage has not been completed, @xpage_done is not modified.
+ *
+ * @cb_start is a pointer to the compression block which needs decompressing
+ * and @cb_size is the size of @cb_start in bytes (8-64kiB).
+ *
+ * Return 0 if success or -EOVERFLOW on error in the compressed stream.
+ * @xpage_done indicates whether the target page (@dest_pages[@xpage]) was
+ * completed during the decompression of the compression block (@cb_start).
+ *
+ * Warning: This function *REQUIRES* PAGE_CACHE_SIZE >= 4096 or it will blow up
+ * unpredicatbly! You have been warned!
+ *
+ * Note to hackers: This function may not sleep until it has finished accessing
+ * the compression block @cb_start as it is a per-CPU buffer.
+ */
+static int ntfs_decompress(struct page *dest_pages[], int *dest_index,
+		int *dest_ofs, const int dest_max_index, const int dest_max_ofs,
+		const int xpage, char *xpage_done, u8 *const cb_start,
+		const u32 cb_size)
+{
+	/*
+	 * Pointers into the compressed data, i.e. the compression block (cb),
+	 * and the therein contained sub-blocks (sb).
+	 */
+	u8 *cb_end = cb_start + cb_size; /* End of cb. */
+	u8 *cb = cb_start;	/* Current position in cb. */
+	u8 *cb_sb_start = cb;	/* Beginning of the current sb in the cb. */
+	u8 *cb_sb_end;		/* End of current sb / beginning of next sb. */
+
+	/* Variables for uncompressed data / destination. */
+	struct page *dp;	/* Current destination page being worked on. */
+	u8 *dp_addr;		/* Current pointer into dp. */
+	u8 *dp_sb_start;	/* Start of current sub-block in dp. */
+	u8 *dp_sb_end;		/* End of current sb in dp (dp_sb_start +
+				   NTFS_SB_SIZE). */
+	u16 do_sb_start;	/* @dest_ofs when starting this sub-block. */
+	u16 do_sb_end;		/* @dest_ofs of end of this sb (do_sb_start +
+				   NTFS_SB_SIZE). */
+
+	/* Variables for tag and token parsing. */
+	u8 tag;			/* Current tag. */
+	int token;		/* Loop counter for the eight tokens in tag. */
+
+	/* Need this because we can't sleep, so need two stages. */
+	int completed_pages[dest_max_index - *dest_index + 1];
+	int nr_completed_pages = 0;
+
+	/* Default error code. */
+	int err = -EOVERFLOW;
+	
+	ntfs_debug("Entering, cb_size = 0x%x.", cb_size);
+do_next_sb:
+	ntfs_debug("Beginning sub-block at offset = 0x%x in the cb.",
+			cb - cb_start);
+
+	/* Have we reached the end of the compression block? */
+	if (cb == cb_end || !le16_to_cpup(cb)) {
+		int i;
+
+		ntfs_debug("Completed. Returning success (0).");
+		err = 0;
+return_error:
+		/* We can sleep from now on, so we reenable preemption. */
+		preempt_enable();
+		/* Second stage: finalize completed pages. */
+		for (i = 0; i < nr_completed_pages; i++) {
+			int di = completed_pages[i];
+
+			dp = dest_pages[di];
+			flush_dcache_page(dp);
+			kunmap(dp);
+			SetPageUptodate(dp);
+			UnlockPage(dp);
+			if (di == xpage)
+				*xpage_done = 1;
+			else
+				page_cache_release(dp);
+			dest_pages[di] = NULL;
+		}
+		return err;
+	}
+
+	/* Setup offsets for the current sub-block destination. */
+	do_sb_start = *dest_ofs;
+	do_sb_end = do_sb_start + NTFS_SB_SIZE;
+	
+	/* Check that we are still within allowed boundaries. */
+	if (*dest_index == dest_max_index && do_sb_end > dest_max_ofs)
+		goto return_overflow;
+
+	/* Does the minimum size of a compressed sb overflow valid range? */
+	if (cb + 6 > cb_end)
+		goto return_overflow;
+
+	/* Setup the current sub-block source pointers and validate range. */
+	cb_sb_start = cb;
+	cb_sb_end = cb_sb_start + (le16_to_cpup(cb) & NTFS_SB_SIZE_MASK) + 3;
+	if (cb_sb_end > cb_end)
+		goto return_overflow;
+
+	/* Get the current destination page. */
+	dp = dest_pages[*dest_index];
+	if (!dp) {
+		/* No page present. Skip decompression of this sub-block. */
+		cb = cb_sb_end;
+
+		/* Advance destination position to next sub-block. */
+		*dest_ofs = (*dest_ofs + NTFS_SB_SIZE) & ~PAGE_CACHE_MASK;
+		if (!*dest_ofs && (++*dest_index > dest_max_index))
+			goto return_overflow;
+		goto do_next_sb;
+	}
+
+	/* We have a valid destination page. Setup the destination pointers. */
+	dp_addr = (u8*)page_address(dp) + do_sb_start;
+
+	/* Now, we are ready to process the current sub-block (sb). */
+	if (!(le16_to_cpup(cb) & NTFS_SB_IS_COMPRESSED)) {
+		ntfs_debug("Found uncompressed sub-block.");
+		/* This sb is not compressed, just copy it into destination. */
+
+		/* Advance source position to first data byte. */
+		cb += 2;
+
+		/* An uncompressed sb must be full size. */
+		if (cb_sb_end - cb != NTFS_SB_SIZE)
+			goto return_overflow;
+
+		/* Copy the block and advance the source position. */
+		memcpy(dp_addr, cb, NTFS_SB_SIZE);
+		cb += NTFS_SB_SIZE;
+
+		/* Advance destination position to next sub-block. */
+		*dest_ofs += NTFS_SB_SIZE;
+		if (!(*dest_ofs &= ~PAGE_CACHE_MASK)) {
+finalize_page:
+			/*
+			 * First stage: add current page index to array of
+			 * completed pages.
+			 */
+			completed_pages[nr_completed_pages++] = *dest_index;
+			if (++*dest_index > dest_max_index)
+				goto return_overflow;
+		}
+		goto do_next_sb;
+	}
+	ntfs_debug("Found compressed sub-block.");
+	/* This sb is compressed, decompress it into destination. */
+
+	/* Setup destination pointers. */
+	dp_sb_start = dp_addr;
+	dp_sb_end = dp_sb_start + NTFS_SB_SIZE;
+
+	/* Forward to the first tag in the sub-block. */
+	cb += 2;
+do_next_tag:
+	if (cb == cb_sb_end) {
+		/* Check if the decompressed sub-block was not full-length. */
+		if (dp_addr < dp_sb_end) {
+			int nr_bytes = do_sb_end - *dest_ofs;
+
+			ntfs_debug("Filling incomplete sub-block with "
+					"zeroes.");
+			/* Zero remainder and update destination position. */
+			memset(dp_addr, 0, nr_bytes);
+			*dest_ofs += nr_bytes;
+		}
+		/* We have finished the current sub-block. */
+		if (!(*dest_ofs &= ~PAGE_CACHE_MASK))
+			goto finalize_page;
+		goto do_next_sb;
+	}
+
+	/* Check we are still in range. */
+	if (cb > cb_sb_end || dp_addr > dp_sb_end)
+		goto return_overflow;
+
+	/* Get the next tag and advance to first token. */
+	tag = *cb++;
+	//ntfs_debug("Found tag = 0x%x.", tag);
+
+	/* Parse the eight tokens described by the tag. */
+	for (token = 0; token < 8; token++, tag >>= 1) {
+		u16 lg, pt, length, max_non_overlap;
+		register u16 i;
+		u8 *dp_back_addr;
+
+		/* Check if we are done / still in range. */
+		if (cb >= cb_sb_end || dp_addr > dp_sb_end)
+			break;
+
+		/* Determine token type and parse appropriately.*/
+		if ((tag & NTFS_TOKEN_MASK) == NTFS_SYMBOL_TOKEN) {
+			//ntfs_debug("Found symbol token = %c (0x%x).", *cb,
+			//		*cb);
+			/*
+			 * We have a symbol token, copy the symbol across, and
+			 * advance the source and destination positions.
+			 */
+			*dp_addr++ = *cb++;
+			++*dest_ofs;
+
+			/* Continue with the next token. */
+			continue;
+		}
+
+		//ntfs_debug("Found phrase token = 0x%x.", le16_to_cpup(cb));
+		/* 
+		 * We have a phrase token. Make sure it is not the first tag in
+		 * the sb as this is illegal and would confuse the code below.
+		 */
+		if (dp_addr == dp_sb_start)
+			goto return_overflow;
+
+		/*
+		 * Determine the number of bytes to go back (p) and the number
+		 * of bytes to copy (l). We use an optimized algorithm in which
+		 * we first calculate log2(current destination position in sb),
+		 * which allows determination of l and p in O(1) rather than
+		 * O(n). We just need an arch-optimized log2() function now.
+		 */
+		lg = 0;
+		for (i = *dest_ofs - do_sb_start - 1; i >= 0x10; i >>= 1)
+			lg++;
+
+		/* Get the phrase token into i. */
+		pt = le16_to_cpup(cb);
+
+		/*
+		 * Calculate starting position of the byte sequence in
+		 * the destination using the fact that p = (pt >> (12 - lg)) + 1
+		 * and make sure we don't go too far back.
+		 */
+		dp_back_addr = dp_addr - (pt >> (12 - lg)) - 1;
+		if (dp_back_addr < dp_sb_start)
+			goto return_overflow;
+
+		/* Now calculate the length of the byte sequence. */
+		length = (pt & (0xfff >> lg)) + 3;
+#if 0
+		ntfs_debug("starting position = 0x%x, back pointer = 0x%x, "
+				"length = 0x%x.", *dest_ofs - do_sb_start -
+				1, (pt >> (12 - lg)) + 1, length);
+#endif
+		/* Advance destination position and verify it is in range. */
+		*dest_ofs += length;
+		if (*dest_ofs > do_sb_end)
+			goto return_overflow;
+
+		/* The number of non-overlapping bytes. */
+		max_non_overlap = dp_addr - dp_back_addr;
+
+		if (length <= max_non_overlap) {
+			//ntfs_debug("Found non-overlapping byte sequence.");
+			/* The byte sequence doesn't overlap, just copy it. */
+			memcpy(dp_addr, dp_back_addr, length);
+
+			/* Advance destination pointer. */
+			dp_addr += length;
+		} else {
+			//ntfs_debug("Found overlapping byte sequence.");
+			/*
+			 * The byte sequence does overlap, copy non-overlapping
+			 * part and then do a slow byte by byte copy for the
+			 * overlapping part. Also, advance the destination
+			 * pointer.
+			 */
+			memcpy(dp_addr, dp_back_addr, max_non_overlap);
+			dp_addr += max_non_overlap;
+			dp_back_addr += max_non_overlap;
+			length -= max_non_overlap;
+			while (length--)
+				*dp_addr++ = *dp_back_addr++;
+		}
+
+		/* Advance source position and continue with the next token. */
+		cb += 2;
+	}
+
+	/* No tokens left in the current tag. Continue with the next tag. */
+	goto do_next_tag;
+
+return_overflow:
+	ntfs_error(NULL, "Failed. Returning -EOVERFLOW.\n");
+	goto return_error;
+}
+
+/**
+ * ntfs_file_read_compressed_block - read a compressed block into the page cache
+ * @page:	locked page in the compression block(s) we need to read
+ *
+ * When we are called the page has already been verified to be locked and the
+ * attribute is known to be non-resident, not encrypted, but compressed.
+ *
+ * 1. Determine which compression block(s) @page is in.
+ * 2. Get hold of all pages corresponding to this/these compression block(s).
+ * 3. Read the (first) compression block.
+ * 4. Decompress it into the corresponding pages.
+ * 5. Throw the compressed data away and proceed to 3. for the next compression
+ *    block or return success if no more compression blocks left.
+ *
+ * Warning: We have to be careful what we do about existing pages. They might
+ * have been written to so that we would lose data if we were to just overwrite
+ * them with the out-of-date uncompressed data.
+ *
+ * FIXME: For PAGE_CACHE_SIZE > cb_size we are not doing the Right Thing(TM) at
+ * the end of the file I think. We need to detect this case and zero the out
+ * of bounds remainder of the page in question and mark it as handled. At the
+ * moment we would just return -EIO on such a page. This bug will only become
+ * apparent if pages are above 8kiB and the NTFS volume only uses 512 byte
+ * clusters so is probably not going to be seen by anyone. Still this should
+ * be fixed. (AIA)
+ *
+ * FIXME: Again for PAGE_CACHE_SIZE > cb_size we are screwing up both in
+ * handling sparse and compressed cbs. (AIA)
+ */
+int ntfs_file_read_compressed_block(struct page *page)
+{
+	struct address_space *mapping = page->mapping;
+	ntfs_inode *ni = NTFS_I(mapping->host);
+	ntfs_volume *vol = ni->vol;
+	kdev_t dev = vol->sb->s_dev;
+	unsigned long block_size = vol->sb->s_blocksize;
+	unsigned char block_size_bits = vol->sb->s_blocksize_bits;
+	u8 *cb, *cb_pos, *cb_end;
+	struct buffer_head **bhs;
+	unsigned long offset, index = page->index;
+	u32 cb_size = ni->_ICF(compression_block_size);
+	u64 cb_size_mask = cb_size - 1UL;
+	VCN vcn;
+	LCN lcn;
+	/* The first wanted vcn (minimum alignment is PAGE_CACHE_SIZE). */
+	VCN start_vcn = (((s64)index << PAGE_CACHE_SHIFT) & ~cb_size_mask) >>
+			vol->cluster_size_bits;
+	/*
+	 * The first vcn after the last wanted vcn (minumum alignment is again
+	 * PAGE_CACHE_SIZE.
+	 */
+	VCN end_vcn = ((((s64)(index + 1UL) << PAGE_CACHE_SHIFT) + cb_size - 1)
+			& ~cb_size_mask) >> vol->cluster_size_bits;
+	/* Number of compression blocks (cbs) in the wanted vcn range. */
+	unsigned int nr_cbs = (end_vcn - start_vcn) << vol->cluster_size_bits
+			>> ni->_ICF(compression_block_size_bits);
+	/*
+	 * Number of pages required to store the uncompressed data from all
+	 * compression blocks (cbs) overlapping @page. Due to alignment
+	 * guarantees of start_vcn and end_vcn, no need to round up here.
+	 */
+	unsigned int nr_pages = (end_vcn - start_vcn) <<
+			vol->cluster_size_bits >> PAGE_CACHE_SHIFT;
+	unsigned int xpage, max_page, cur_page, cur_ofs, i;
+	unsigned int cb_clusters, cb_max_ofs;
+	int block, max_block, cb_max_page, bhs_size, nr_bhs, err = 0;
+	struct page **pages;
+	unsigned char xpage_done = 0;
+
+	ntfs_debug("Entering, page->index = 0x%lx, cb_size = 0x%x, nr_pages = "
+			"%i.", index, cb_size, nr_pages);
+
+	/*
+	 * Uncommenting the below line results in the compressed data being
+	 * read without any decompression. Compression blocks are padded with
+	 * zeroes in order to give them in their proper alignments. I am
+	 * leaving this here as it is a handy debugging / studying tool for
+	 * compressed data.
+	 */
+#if 0
+	return block_read_full_page(page, ntfs_file_get_block);
+#endif
+	pages = kmalloc(nr_pages * sizeof(struct page *), GFP_NOFS);
+
+	/* Allocate memory to store the buffer heads we need. */
+	bhs_size = cb_size / block_size * sizeof(struct buffer_head *);
+	bhs = kmalloc(bhs_size, GFP_NOFS);
+
+	if (unlikely(!pages || !bhs)) {
+		kfree(bhs);
+		kfree(pages);
+		SetPageError(page);
+		UnlockPage(page);
+		ntfs_error(vol->sb, "Failed to allocate internal buffers.");
+		return -ENOMEM;
+	}
+
+	/*
+	 * We have already been given one page, this is the one we must do.
+	 * Once again, the alignment guarantees keep it simple.
+	 */
+	offset = start_vcn << vol->cluster_size_bits >> PAGE_CACHE_SHIFT;
+	xpage = index - offset;
+	pages[xpage] = page;
+	/*
+	 * The remaining pages need to be allocated and inserted into the page
+	 * cache, alignment guarantees keep all the below much simpler. (-8
+	 */
+	max_page = ((VFS_I(ni)->i_size + PAGE_CACHE_SIZE - 1) >>
+			PAGE_CACHE_SHIFT) - offset;
+	if (nr_pages < max_page)
+		max_page = nr_pages;
+	for (i = 0; i < max_page; i++, offset++) {
+		if (i != xpage)
+			pages[i] = grab_cache_page_nowait(mapping, offset);
+		page = pages[i];
+		if (page) {
+			/*
+			 * We only (re)read the page if it isn't already read
+			 * in and/or dirty or we would be losing data or at
+			 * least wasting our time.
+			 */
+			if (!PageDirty(page) && (!Page_Uptodate(page) ||
+					PageError(page))) {
+				ClearPageError(page);
+				kmap(page);
+				continue;
+			}
+			UnlockPage(page);
+			page_cache_release(page);
+			pages[i] = NULL;
+		}
+	}
+
+	/*
+	 * We have the run list, and all the destination pages we need to fill.
+	 * Now read the first compression block.
+	 */
+	cur_page = 0;
+	cur_ofs = 0;
+	cb_clusters = ni->_ICF(compression_block_clusters);
+do_next_cb:
+	nr_cbs--;
+	nr_bhs = 0;
+
+	/* Read all cb buffer heads one cluster run at a time. */
+	for (vcn = start_vcn, start_vcn += cb_clusters; vcn < start_vcn;
+			vcn++) {
+		BOOL is_retry = FALSE;
+retry_remap:
+		/* Make sure we are not overflowing the file limits. */
+		if (vcn << vol->cluster_size_bits >= ni->initialized_size) {
+			/* Overflow, just zero this region. */
+			// TODO: AIA
+		}
+		/* Find lcn of vcn and convert it into blocks. */
+		read_lock(&ni->run_list.lock);
+		lcn = vcn_to_lcn(ni->run_list.rl, vcn);
+		read_unlock(&ni->run_list.lock);
+		ntfs_debug("Reading vcn = 0x%Lx, lcn = 0x%Lx.",
+				(long long)vcn, (long long)lcn);
+		if (lcn < 0) {
+			/*
+			 * When we reach the first sparse cluster we have
+			 * finished with the cb.
+			 */
+			if (lcn == LCN_HOLE)
+				break;
+			if (is_retry || lcn != LCN_RL_NOT_MAPPED)
+				goto rl_err;
+			is_retry = TRUE;
+			/* Map run list of current extent and retry. */
+			if (!map_run_list(ni, vcn))
+				goto retry_remap;
+			goto map_rl_err;
+		}
+		block = lcn << vol->cluster_size_bits >> block_size_bits;
+		/* Read the lcn from device in chunks of block_size bytes. */
+		max_block = block + (vol->cluster_size >> block_size_bits);
+		do {
+			// TODO: Need overflow checks here, too! (AIA)
+			ntfs_debug("block = 0x%x.", block);
+			if (unlikely(!(bhs[nr_bhs] = getblk(dev, block,
+					block_size))))
+				goto getblk_err;
+			nr_bhs++;
+		} while (++block < max_block);
+	}
+
+	/* Setup and initiate io on all buffer heads. */
+	for (i = 0; i < nr_bhs; i++) {
+		struct buffer_head *tbh = bhs[i];
+
+		if (buffer_uptodate(tbh))
+			continue;
+
+		lock_buffer(tbh);
+		get_bh(tbh);
+		tbh->b_end_io = end_buffer_io_sync;
+		submit_bh(READ, tbh);
+	}
+
+	/* Wait for io completion on all buffer heads. */
+	for (i = 0; i < nr_bhs; i++) {
+		struct buffer_head *tbh = bhs[i];
+
+		if (buffer_uptodate(tbh))
+			continue;
+
+		wait_on_buffer(tbh);
+		if (!buffer_uptodate(tbh))
+			goto read_err;
+	}
+
+	/*
+	 * Get the compression buffer corresponding to the current CPU. We must
+	 * not sleep any more until we are finished with the compression buffer.
+	 * If on a preemptible kernel, now disable preemption.
+	 */
+	preempt_disable();
+	cb = ntfs_compression_buffers[smp_processor_id()];
+
+	BUG_ON(!cb);
+
+	cb_pos = cb;
+	cb_end = cb + cb_size;
+
+	/* Copy the buffer heads into the contiguous buffer. */
+	for (i = 0; i < nr_bhs; i++) {
+		memcpy(cb_pos, bhs[i]->b_data, block_size);
+		cb_pos += block_size;
+	}
+
+	/* Just a precaution. */
+	if (cb_pos + 2 <= cb + cb_size)
+		*(u16*)cb_pos = 0;
+
+	/* Reset cb_pos back to the beginning. */
+	cb_pos = cb;
+
+	/* We now have both source (if present) and destination. */
+	ntfs_debug("Successfully read the compression block.");
+
+	/* The last page and maximum offset within it for the current cb. */
+	cb_max_page = (cur_page << PAGE_CACHE_SHIFT) + cur_ofs + cb_size;
+	cb_max_ofs = cb_max_page & ~PAGE_CACHE_MASK;
+	cb_max_page >>= PAGE_CACHE_SHIFT;
+
+	/* Catch end of file inside a compression block. */
+	if (cb_max_page > max_page)
+		cb_max_page = max_page;
+
+	if (vcn == start_vcn - cb_clusters) {
+		/* Sparse cb, zero out page range overlapping the cb. */
+		ntfs_debug("Found sparse compression block.");
+		/* We can sleep from now on, so we reenable preemption. */
+		preempt_enable();
+		if (cb_max_ofs)
+			cb_max_page--;
+		for (; cur_page < cb_max_page; cur_page++) {
+			page = pages[cur_page];
+			if (page) {
+				/*
+				 * FIXME: Using clear_page() will become wrong
+				 * when we get PAGE_CACHE_SIZE != PAGE_SIZE but
+				 * for now there is no problem.
+				 */
+				if (likely(!cur_ofs))
+					clear_page(page_address(page));
+				else
+					memset(page_address(page) + cur_ofs, 0,
+							PAGE_CACHE_SIZE -
+							cur_ofs);
+				flush_dcache_page(page);
+				kunmap(page);
+				SetPageUptodate(page);
+				UnlockPage(page);
+				if (cur_page == xpage)
+					xpage_done = 1;
+				else
+					page_cache_release(page);
+				pages[cur_page] = NULL;
+			}
+			cb_pos += PAGE_CACHE_SIZE - cur_ofs;
+			cur_ofs = 0;
+			if (cb_pos >= cb_end)
+				break;
+		}
+		/* If we have a partial final page, deal with it now. */
+		if (cb_max_ofs && cb_pos < cb_end) {
+			page = pages[cur_page];
+			if (page)
+				memset(page_address(page) + cur_ofs, 0,
+						cb_max_ofs - cur_ofs);
+			cb_pos += cb_max_ofs - cur_ofs;
+			cur_ofs = cb_max_ofs;
+		}
+	} else if (vcn == start_vcn) {
+		/* We can't sleep so we need two stages. */
+		unsigned int cur2_page = cur_page;
+		unsigned int cur_ofs2 = cur_ofs;
+		u8 *cb_pos2 = cb_pos;
+
+		ntfs_debug("Found uncompressed compression block.");
+		/* Uncompressed cb, copy it to the destination pages. */
+		/*
+		 * TODO: As a big optimization, we could detect this case
+		 * before we read all the pages and use block_read_full_page()
+		 * on all full pages instead (we still have to treat partial
+		 * pages especially but at least we are getting rid of the
+		 * synchronous io for the majority of pages.
+		 * Or if we choose not to do the read-ahead/-behind stuff, we
+		 * could just return block_read_full_page(pages[xpage]) as long
+		 * as PAGE_CACHE_SIZE <= cb_size.
+		 */
+		if (cb_max_ofs)
+			cb_max_page--;
+		/* First stage: copy data into destination pages. */
+		for (; cur_page < cb_max_page; cur_page++) {
+			page = pages[cur_page];
+			if (page)
+				memcpy(page_address(page) + cur_ofs, cb_pos,
+						PAGE_CACHE_SIZE - cur_ofs);
+			cb_pos += PAGE_CACHE_SIZE - cur_ofs;
+			cur_ofs = 0;
+			if (cb_pos >= cb_end)
+				break;
+		}
+		/* If we have a partial final page, deal with it now. */
+		if (cb_max_ofs && cb_pos < cb_end) {
+			page = pages[cur_page];
+			if (page)
+				memcpy(page_address(page) + cur_ofs, cb_pos,
+						cb_max_ofs - cur_ofs);
+			cb_pos += cb_max_ofs - cur_ofs;
+			cur_ofs = cb_max_ofs;
+		}
+		/* We can sleep from now on, so we reenable preemption. */
+		preempt_enable();
+		/* Second stage: finalize pages. */
+		for (; cur2_page < cb_max_page; cur2_page++) {
+			page = pages[cur2_page];
+			if (page) {
+				flush_dcache_page(page);
+				kunmap(page);
+				SetPageUptodate(page);
+				UnlockPage(page);
+				if (cur2_page == xpage)
+					xpage_done = 1;
+				else
+					page_cache_release(page);
+				pages[cur2_page] = NULL;
+			}
+			cb_pos2 += PAGE_CACHE_SIZE - cur_ofs2;
+			cur_ofs2 = 0;
+			if (cb_pos2 >= cb_end)
+				break;
+		}
+	} else {
+		/* Compressed cb, decompress it into the destination page(s). */
+		unsigned int prev_cur_page = cur_page;
+
+		ntfs_debug("Found compressed compression block.");
+		err = ntfs_decompress(pages, &cur_page, &cur_ofs,
+				cb_max_page, cb_max_ofs, xpage, &xpage_done,
+				cb_pos,	cb_size - (cb_pos - cb));
+		/*
+		 * We can sleep from now on, preemption already reenabled by
+		 * ntfs_decompess.
+		 */
+		if (err) {
+			ntfs_error(vol->sb, "ntfs_decompress() failed with "
+					"error code %i. Skipping this "
+					"compression block.\n", -err);
+			/* Release the unfinished pages. */
+			for (; prev_cur_page < cur_page; prev_cur_page++) {
+				page = pages[prev_cur_page];
+				if (page) {
+					if (prev_cur_page == xpage &&
+							!xpage_done)
+						SetPageError(page);
+					flush_dcache_page(page);
+					kunmap(page);
+					UnlockPage(page);
+					if (prev_cur_page != xpage)
+						page_cache_release(page);
+					pages[prev_cur_page] = NULL;
+				}
+			}
+		}
+	}
+
+	/* Release the buffer heads. */
+	for (i = 0; i < nr_bhs; i++)
+		brelse(bhs[i]);
+
+	/* Do we have more work to do? */
+	if (nr_cbs)
+		goto do_next_cb;
+
+	/* We no longer need the list of buffer heads. */
+	kfree(bhs);
+
+	/* Clean up if we have any pages left. Should never happen. */
+	for (cur_page = 0; cur_page < max_page; cur_page++) {
+		page = pages[cur_page];
+		if (page) {
+			ntfs_error(vol->sb, "Still have pages left! "
+					"Terminating them with extreme "
+					"prejudice.");
+			if (cur_page == xpage && !xpage_done)
+				SetPageError(page);
+			flush_dcache_page(page);
+			kunmap(page);
+			UnlockPage(page);
+			if (cur_page != xpage)
+				page_cache_release(page);
+			pages[cur_page] = NULL;
+		}
+	}
+
+	/* If we have completed the requested page, we return success. */
+	if (likely(xpage_done))
+		return 0;
+
+	ntfs_debug("Failed. Returning error code %s.", err == -EOVERFLOW ?
+			"EOVERFLOW" : (!err ? "EIO" : "unkown error"));
+	return err < 0 ? err : -EIO;
+
+read_err:
+	ntfs_error(vol->sb, "IO error while reading compressed data.");
+	/* Release the buffer heads. */
+	for (i = 0; i < nr_bhs; i++)
+		brelse(bhs[i]);
+	goto err_out;
+
+map_rl_err:
+	ntfs_error(vol->sb, "map_run_list() failed. Cannot read compression "
+			"block.");
+	goto err_out;
+
+rl_err:
+	ntfs_error(vol->sb, "vcn_to_lcn() failed. Cannot read compression "
+			"block.");
+	goto err_out;
+
+getblk_err:
+	ntfs_error(vol->sb, "getblk() failed. Cannot read compression block.");
+
+err_out:
+	kfree(bhs);
+	for (i = cur_page; i < max_page; i++) {
+		page = pages[i];
+		if (page) {
+			if (i == xpage && !xpage_done)
+				SetPageError(page);
+			flush_dcache_page(page);
+			kunmap(page);
+			UnlockPage(page);
+			if (i != xpage)
+				page_cache_release(page);
+		}
+	}
+	return -EIO;
+}
+

fs/ntfs/debug.c

+/*
+ * debug.c - NTFS kernel debug support. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "debug.h"
+
+/*
+ * A static buffer to hold the error string being displayed and a spinlock
+ * to protect concurrent accesses to it.
+ */
+static char err_buf[1024];
+static spinlock_t err_buf_lock = SPIN_LOCK_UNLOCKED;
+
+/**
+ * __ntfs_warning - output a warning to the syslog
+ * @function:	name of function outputting the warning
+ * @sb:		super block of mounted ntfs filesystem
+ * @fmt:	warning string containing format specifications
+ * @...:	a variable number of arguments specified in @fmt
+ *
+ * Outputs a warning to the syslog for the mounted ntfs filesystem described
+ * by @sb.
+ *
+ * @fmt and the corresponding @... is printf style format string containing
+ * the warning string and the corresponding format arguments, respectively.
+ *
+ * @function is the name of the function from which __ntfs_warning is being
+ * called.
+ *
+ * Note, you should be using debug.h::ntfs_warning(@sb, @fmt, @...) instead
+ * as this provides the @function parameter automatically.
+ */
+void __ntfs_warning(const char *function, const struct super_block *sb,
+		const char *fmt, ...)
+{
+	va_list args;
+	int flen = 0;
+
+	if (function)
+		flen = strlen(function);
+	spin_lock(&err_buf_lock);
+	va_start(args, fmt);
+	vsnprintf(err_buf, sizeof(err_buf), fmt, args);
+	va_end(args);
+	if (sb)
+		printk(KERN_ERR "NTFS-fs warning (device %s): %s(): %s\n",
+				sb->s_id, flen ? function : "", err_buf);
+	else
+		printk(KERN_ERR "NTFS-fs warning: %s(): %s\n",
+				flen ? function : "", err_buf);
+	spin_unlock(&err_buf_lock);
+}
+
+/**
+ * __ntfs_error - output an error to the syslog
+ * @function:	name of function outputting the error
+ * @sb:		super block of mounted ntfs filesystem
+ * @fmt:	error string containing format specifications
+ * @...:	a variable number of arguments specified in @fmt
+ *
+ * Outputs an error to the syslog for the mounted ntfs filesystem described
+ * by @sb.
+ *
+ * @fmt and the corresponding @... is printf style format string containing
+ * the error string and the corresponding format arguments, respectively.
+ *
+ * @function is the name of the function from which __ntfs_error is being
+ * called.
+ *
+ * Note, you should be using debug.h::ntfs_error(@sb, @fmt, @...) instead
+ * as this provides the @function parameter automatically.
+ */
+void __ntfs_error(const char *function, const struct super_block *sb,
+		const char *fmt, ...)
+{
+	va_list args;
+	int flen = 0;
+
+	if (function)
+		flen = strlen(function);
+	spin_lock(&err_buf_lock);
+	va_start(args, fmt);
+	vsnprintf(err_buf, sizeof(err_buf), fmt, args);
+	va_end(args);
+	if (sb)
+		printk(KERN_ERR "NTFS-fs error (device %s): %s(): %s\n",
+				sb->s_id, flen ? function : "", err_buf);
+	else
+		printk(KERN_ERR "NTFS-fs error: %s(): %s\n",
+				flen ? function : "", err_buf);
+	spin_unlock(&err_buf_lock);
+}
+
+#ifdef DEBUG
+
+/* If 1, output debug messages, and if 0, don't. */
+int debug_msgs = 0;
+
+void __ntfs_debug (const char *file, int line, const char *function,
+		const char *fmt, ...)
+{
+	va_list args;
+	int flen = 0;
+
+	if (!debug_msgs)
+		return;
+	if (function)
+		flen = strlen(function);
+	spin_lock(&err_buf_lock);
+	va_start(args, fmt);
+	vsnprintf(err_buf, sizeof(err_buf), fmt, args);
+	va_end(args);
+	printk(KERN_DEBUG "NTFS-fs DEBUG (%s, %d): %s: %s\n",
+		file, line, flen ? function : "", err_buf);
+	spin_unlock(&err_buf_lock);
+}
+
+/* Dump a run list. Caller has to provide synchronisation for @rl. */
+void ntfs_debug_dump_runlist(const run_list_element *rl)
+{
+	int i;
+	const char *lcn_str[5] = { "LCN_HOLE         ", "LCN_RL_NOT_MAPPED",
+				   "LCN_ENOENT       ", "LCN_EINVAL       ",
+				   "LCN_unknown      " };
+
+	if (!debug_msgs)
+		return;
+	printk(KERN_DEBUG "NTFS-fs DEBUG: Dumping run list (values "
+			"in hex):\n");
+	if (!rl) {
+		printk(KERN_DEBUG "Run list not present.\n");
+		return;
+	}
+	printk(KERN_DEBUG "VCN              LCN               Run length\n");
+	for (i = 0; ; i++) {
+		LCN lcn = (rl + i)->lcn;
+
+		if (lcn < (LCN)0) {
+			int index = -lcn - 1;
+
+			if (index > -LCN_EINVAL - 1)
+				index = 4;
+			printk(KERN_DEBUG "%-16Lx %s %-16Lx%s\n",
+				(rl + i)->vcn, lcn_str[index],
+				(rl + i)->length, (rl + i)->length ?
+				"" : " (run list end)");
+		} else
+			printk(KERN_DEBUG "%-16Lx %-16Lx  %-16Lx%s\n",
+				(rl + i)->vcn, (rl + i)->lcn,
+				(rl + i)->length, (rl + i)->length ?
+				"" : " (run list end)");
+		if (!(rl + i)->length)
+			break;
+	}
+}
+
+#endif
+

fs/ntfs/debug.h

+/*
+ * debug.h - NTFS kernel debug support. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_DEBUG_H
+#define _LINUX_NTFS_DEBUG_H
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/fs.h>
+
+#include "inode.h"
+#include "attrib.h"
+
+#ifdef DEBUG
+
+extern int debug_msgs;
+
+#if 0 /* Fool kernel-doc since it doesn't do macros yet */
+/**
+ * ntfs_debug - write a debug level message to syslog
+ * @f:		a printf format string containing the message
+ * @...:	the variables to substitute into @f
+ *
+ * ntfs_debug() writes a DEBUG level message to the syslog but only if the
+ * driver was compiled with -DDEBUG. Otherwise, the call turns into a NOP.
+ */
+static void ntfs_debug(const char *f, ...);
+#endif
+
+extern void __ntfs_debug (const char *file, int line, const char *function,
+	const char *format, ...) __attribute__ ((format (printf, 4, 5)));
+#define ntfs_debug(f, a...)						\
+	__ntfs_debug(__FILE__, __LINE__, __FUNCTION__, f, ##a)
+
+extern void ntfs_debug_dump_runlist(const run_list_element *rl);
+
+#else	/* !DEBUG */
+
+#define ntfs_debug(f, a...)		do {} while (0)
+#define ntfs_debug_dump_runlist(rl)	do {} while (0)
+
+#endif	/* !DEBUG */
+
+extern void __ntfs_warning(const char *function, const struct super_block *sb,
+		const char *fmt, ...) __attribute__ ((format (printf, 3, 4)));
+#define ntfs_warning(sb, f, a...)	__ntfs_warning(__FUNCTION__, sb, f, ##a)
+
+extern void __ntfs_error(const char *function, const struct super_block *sb,
+		const char *fmt, ...) __attribute__ ((format (printf, 3, 4)));
+#define ntfs_error(sb, f, a...)		__ntfs_error(__FUNCTION__, sb, f, ##a)
+
+#endif /* _LINUX_NTFS_DEBUG_H */
+

fs/ntfs/dir.c

-/*
- * dir.c
+/**
+ * dir.c - NTFS kernel directory operations. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
- * Copyright (C) 1995-1997, 1999 Martin von Lwis
- * Copyright (C) 1999 Steve Dodd
- * Copyright (C) 1999 Joseph Malicki
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#include "ntfstypes.h"
-#include "struct.h"
-#include "dir.h"
-#include "macros.h"
-
-#include <linux/errno.h>
-#include "super.h"
-#include "inode.h"
-#include "attr.h"
-#include "support.h"
-#include "util.h"
-#include <linux/smp_lock.h>
-#include <linux/bitops.h>
-
-static char I30[] = "$I30";
-
-/* An index record should start with INDX, and the last word in each block
- * should contain the check value. If it passes, the original values need to
- * be restored. */
-int ntfs_check_index_record(ntfs_inode *ino, char *record)
-{
-	return ntfs_fixup_record(record, "INDX", ino->u.index.recordsize);
-}
-
-static inline int ntfs_is_top(ntfs_u64 stack)
-{
-	return stack == 14;
-}
+#include "ntfs.h"
 
-static int ntfs_pop(ntfs_u64 *stack)
+/**
+ * The little endian Unicode string $I30 as a global constant.
+ */
+const uchar_t I30[5] = { const_cpu_to_le16('$'), const_cpu_to_le16('I'),
+		const_cpu_to_le16('3'),	const_cpu_to_le16('0'),
+		const_cpu_to_le16(0) };
+
+/**
+ * ntfs_lookup_inode_by_name - find an inode in a directory given its name
+ * @dir_ni:	ntfs inode of the directory in which to search for the name
+ * @uname:	Unicode name for which to search in the directory
+ * @uname_len:	length of the name @uname in Unicode characters
+ *
+ * Look for an inode with name @uname in the directory with inode @dir_ni.
+ * ntfs_lookup_inode_by_name() walks the contents of the directory looking for
+ * the Unicode name. If the name is found in the directory, the corresponding
+ * inode number (>= 0) is returned as a mft reference in cpu format, i.e. it
+ * is a 64-bit number containing the sequence number.
+ *
+ * On error, a negative value is returned corresponding to the error code. In
+ * particular if the inode is not found -ENOENT is returned. Note that you
+ * can't just check the return value for being negative, you have to check the
+ * inode number for being negative which you can extract using MREC(return
+ * value).
+ *
+ * Note, @uname_len does not include the (optional) terminating NULL character.
+ */
+u64 ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const uchar_t *uname,
+		const int uname_len)
 {
-	static int width[16] = {1,2,1,3,1,2,1,4,1,2,1,3,1,2,1,-1};
-	int res = -1;
-	
-	switch (width[*stack & 15]) {
-	case 1:
-		res = (int)((*stack & 15) >> 1);
-		*stack >>= 4;
-		break;
-	case 2:
-		res = (int)(((*stack & 63) >> 2) + 7);
-		*stack >>= 6;
-		break;
-	case 3:
-		res = (int)(((*stack & 255) >> 3) + 23);
-		*stack >>= 8;
-		break;
-	case 4:
-		res = (int)(((*stack & 1023) >> 4) + 55);
-		*stack >>= 10;
+	ntfs_volume *vol = dir_ni->vol;
+	struct super_block *sb = vol->sb;
+	MFT_RECORD *m;
+	INDEX_ROOT *ir;
+	INDEX_ENTRY *ie;
+	INDEX_ALLOCATION *ia;
+	u8 *index_end;
+	u64 mref;
+	attr_search_context *ctx;
+	int err, rc;
+	IGNORE_CASE_BOOL ic;
+	VCN vcn, old_vcn;
+	struct address_space *ia_mapping;
+	struct page *page;
+	u8 *kaddr;
+
+	/* Get hold of the mft record for the directory. */
+	m = map_mft_record(READ, dir_ni);
+	if (IS_ERR(m))
+		goto map_err_out;
+
+	err = get_attr_search_ctx(&ctx, dir_ni, m);
+	if (err)
+		goto unm_err_out;
+
+	/* Find the index root attribute in the mft record. */
+	if (!lookup_attr(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, 0,
+			ctx)) {
+		ntfs_error(sb, "Index root attribute missing in directory "
+				"inode 0x%Lx.",
+				(unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto put_unm_err_out;
+	}
+	/* Get to the index root value (it's been verified in read_inode). */
+	ir = (INDEX_ROOT*)((u8*)ctx->attr +
+			le16_to_cpu(ctx->attr->_ARA(value_offset)));
+	index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
+	/* The first index entry. */
+	ie = (INDEX_ENTRY*)((u8*)&ir->index +
+			le32_to_cpu(ir->index.entries_offset));
+	/*
+	 * Loop until we exceed valid memory (corruption case) or until we
+	 * reach the last entry.
+	 */
+	for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->_IEH(length)))) {
+		/* Bounds checks. */
+		if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie +
+				sizeof(INDEX_ENTRY_HEADER) > index_end ||
+				(u8*)ie + le16_to_cpu(ie->_IEH(key_length)) >
+				index_end)
+			goto dir_err_out;
+		/*
+		 * The last entry cannot contain a name. It can however contain
+		 * a pointer to a child node in the B+tree so we just break out.
+		 */
+		if (ie->_IEH(flags) & INDEX_ENTRY_END)
 			break;
-	default:
-		ntfs_error("Unknown encoding\n");
-	}
-	return res;
-}
-
-static inline unsigned int ntfs_top(void)
-{
-	return 14;
-}
-
-static ntfs_u64 ntfs_push(ntfs_u64 stack, int i)
-{
-	if (i < 7)
-		return (stack << 4) | (i << 1);
-	if (i < 23)
-		return (stack << 6) | ((i - 7) << 2) | 1;
-	if (i < 55)
-		return (stack << 8) | ((i - 23) << 3) | 3;
-	if (i < 120)
-		return (stack << 10) | ((i - 55) << 4) | 7;
-	ntfs_error("Too many entries\n");
-	return ~((ntfs_u64)0);
-}
-
-#if 0
-static void ntfs_display_stack(ntfs_u64 stack)
-{
-	while(!ntfs_is_top(stack))
-	{
-		printf("%d ", ntfs_pop(&stack));
-	}
-	printf("\n");
-}
-#endif
-
-/* True if the entry points to another block of entries. */
-static inline int ntfs_entry_has_subnodes(char *entry)
-{
-	return (NTFS_GETU16(entry + 0xc) & 1);
-}
-
-/* True if it is not the 'end of dir' entry. */
-static inline int ntfs_entry_is_used(char *entry)
-{
-	return !(NTFS_GETU16(entry + 0xc) & 2);
-}
-
-/*
- * Removed RACE for allocating index blocks. But stil not too happy.
- * There might be more races afterwards. (AIA)
+		/*
+		 * If the current entry has a name type of POSIX, the name is
+		 * case sensitive and not otherwise. This has the effect of us
+		 * not being able to access any POSIX file names which collate
+		 * after the non-POSIX one when they only differ in case, but
+		 * anyone doing screwy stuff like that deserves to burn in
+		 * hell... Doing that kind of stuff on NT4 actually causes
+		 * corruption on the partition even when using SP6a and Linux
+		 * is not involved at all.
 		 */
-static int ntfs_allocate_index_block(ntfs_iterate_s *walk)
-{
-	ntfs_attribute *allocation, *bitmap = 0;
-	int error, size, i, bit;
-	ntfs_u8 *bmap;
-	ntfs_io io;
-	ntfs_volume *vol = walk->dir->vol;
-
-	/* Check for allocation attribute. */
-	allocation = ntfs_find_attr(walk->dir, vol->at_index_allocation, I30);
-	if (!allocation) {
-		ntfs_u8 bmp[8];
-		/* Create index allocation attribute. */
-		error = ntfs_create_attr(walk->dir, vol->at_index_allocation,
-					 I30, 0, 0, &allocation);
-		if (error)
-			goto err_ret;
-		ntfs_bzero(bmp, sizeof(bmp));
-		error = ntfs_create_attr(walk->dir, vol->at_bitmap, I30, bmp,
-					 sizeof(bmp), &bitmap);
-		if (error)
-			goto err_ret;
-	} else
-		bitmap = ntfs_find_attr(walk->dir, vol->at_bitmap, I30);
-	if (!bitmap) {
-		ntfs_error("Directory w/o bitmap\n");
-		error = -EINVAL;
-		goto err_ret;
-	}
-	size = bitmap->size;
-	bmap = ntfs_malloc(size);
-	if (!bmap) {
-		error = -ENOMEM;
-		goto err_ret;
+		ic = ie->key.file_name.file_name_type ? IGNORE_CASE :
+				CASE_SENSITIVE;
+		/*
+		 * If the names match perfectly, we are done and return the
+		 * mft reference of the inode (i.e. the inode number together
+		 * with the sequence number for consistency checking. We
+		 * convert it to cpu format before returning.
+		 */
+		if (ntfs_are_names_equal(uname, uname_len,
+				(uchar_t*)&ie->key.file_name.file_name,
+				ie->key.file_name.file_name_length, ic,
+				vol->upcase, vol->upcase_len)) {
+found_it:
+			mref = le64_to_cpu(ie->_IIF(indexed_file));
+			put_attr_search_ctx(ctx);
+			unmap_mft_record(READ, dir_ni);
+			return mref;
 		}
-	io.fn_put = ntfs_put;
-	io.fn_get = ntfs_get;
-try_again:
-	io.param = bmap;
-	io.size = size;
-	error = ntfs_read_attr(walk->dir, vol->at_bitmap, I30, 0, &io);
-	if (error || (io.size != size && (error = -EIO, 1)))
-		goto err_fb_out;
-	/* Allocate a bit. */
-	for (bit = i = 0; i < size; i++) {
-		if (bmap[i] == 0xFF)
+		/*
+		 * Not a perfect match, need to do full blown collation so we
+		 * know which way in the B+tree we have to go.
+		 */
+		rc = ntfs_collate_names(uname, uname_len,
+				(uchar_t*)&ie->key.file_name.file_name,
+				ie->key.file_name.file_name_length, 1,
+				IGNORE_CASE, vol->upcase, vol->upcase_len);
+		/*
+		 * If uname collates before the name of the current entry, there
+		 * is definitely no such name in this index but we might need to
+		 * descend into the B+tree so we just break out of the loop.
+		 */
+		if (rc == -1)
+			break;
+		/* The names are not equal, continue the search. */
+		if (rc)
 			continue;
-		bit = ffz(bmap[i]);
-		if (bit < 8)
+		/*
+		 * Names match with case insensitive comparison, now try the
+		 * case sensitive comparison, which is required for proper
+		 * collation.
+		 */
+		rc = ntfs_collate_names(uname, uname_len,
+				(uchar_t*)&ie->key.file_name.file_name,
+				ie->key.file_name.file_name_length, 1,
+				CASE_SENSITIVE, vol->upcase, vol->upcase_len);
+		if (rc == -1)
 			break;
+		if (rc)
+			continue;
+		/*
+		 * Perfect match, this will never happen as the
+		 * ntfs_are_names_equal() call will have gotten a match but we
+		 * still treat it correctly.
+		 */
+		goto found_it;
 	}
-	if (i >= size) {
-		/* FIXME: Extend bitmap. */
-		error = -EOPNOTSUPP;
-		goto err_fb_out;
-	}
-	/* Get the byte containing our bit again, now taking the BKL. */
-	io.param = bmap;
-	io.size = 1;
-	lock_kernel();
-	error = ntfs_read_attr(walk->dir, vol->at_bitmap, I30, i, &io);
-	if (error || (io.size != 1 && (error = -EIO, 1)))
-		goto err_unl_out;
-	if (ntfs_test_and_set_bit(bmap, bit)) {
-		unlock_kernel();
-		/* Give other process(es) a chance to finish. */
-		schedule();
-		goto try_again;
-	}
-	walk->newblock = (i * 8 + bit) * walk->dir->u.index.clusters_per_record;
-	io.param = bmap;
-	error = ntfs_write_attr(walk->dir, vol->at_bitmap, I30, i, &io);
-	if (error || (io.size != size && (error = -EIO, 1)))
-		goto err_unl_out;
-	/* Change inode on disk, required when bitmap is resident. */
-	error = ntfs_update_inode(walk->dir);
-	if (error)
-		goto err_unl_out;
-	unlock_kernel();
-	ntfs_free(bmap);
-	/* Check whether record is out of allocated range. */
-	size = allocation->size;
-	if (walk->newblock * vol->cluster_size >= size) {
-		/* Build index record. */
-		int hsize;
-		int s1 = walk->dir->u.index.recordsize;
-		int nr_fix = (s1 >> vol->sector_size) + 1;
-		char *record = ntfs_malloc(s1);
-		if (!record) {
-			error = -ENOMEM;
-			goto err_ret;
-		}
-		ntfs_bzero(record, s1);
-		/* Magic */
-		ntfs_memcpy(record, "INDX", 4);
-		/* Offset to fixups */
-		NTFS_PUTU16(record + 4, 0x28);
-		/* Number of fixups. */
-		NTFS_PUTU16(record + 6, nr_fix);
-		/* Log file sequence number - We don't do journalling so we
-		 * just set it to zero which should be the Right Thing. (AIA) */
-		NTFS_PUTU64(record + 8, 0);
-		/* VCN of buffer */
-		NTFS_PUTU64(record + 0x10, walk->newblock);
-		/* Header size. */
-		hsize = 0x10 + 2 * nr_fix;
-		hsize = (hsize + 7) & ~7; /* Align. */
-		NTFS_PUTU16(record + 0x18, hsize);
-		/* Total size of record. */
-		NTFS_PUTU32(record + 0x20, s1 - 0x18);
-		/* Writing the data will extend the attribute. */
-		io.param = record;
-		io.size = s1;
-		io.do_read = 0;
-		error = ntfs_readwrite_attr(walk->dir, allocation, size, &io);
-		ntfs_free(record);
-		if (error || (io.size != s1 && (error = -EIO, 1)))
-			goto err_ret;
-		error = ntfs_update_inode(walk->dir);
-		if (error)
-			goto err_ret;
-	}
-	return 0;
-err_unl_out:
-	unlock_kernel();
-err_fb_out:
-	ntfs_free(bmap);
-err_ret:
-	return error;
-}
-
-/* Write an index block (root or allocation) back to storage.
- * Used is the total number of bytes in buf, including all headers. */
-static int ntfs_index_writeback(ntfs_iterate_s *walk, ntfs_u8 *buf, int block,
-				int used)
-{
-	ntfs_io io;
-	int error;
-	ntfs_attribute *a;
-	ntfs_volume *vol = walk->dir->vol;
-	
-	io.fn_put = 0;
-	io.fn_get = ntfs_get;
-	io.param = buf;
-	if (block == -1) {	/* Index root. */
-		NTFS_PUTU16(buf + 0x14, used - 0x10);
-		/* 0x18 is a copy thereof. */
-		NTFS_PUTU16(buf + 0x18, used - 0x10);
-		io.size = used;
-		error = ntfs_write_attr(walk->dir, vol->at_index_root, I30, 0,
-					&io);
-		if (error || (io.size != used && (error = -EIO, 1)))
-			return error;
-		/* Shrink if necessary. */
-		a = ntfs_find_attr(walk->dir, vol->at_index_root, I30);
-		ntfs_resize_attr(walk->dir, a, used);
-	} else {
-		NTFS_PUTU16(buf + 0x1C, used - 0x18);
-		io.size = walk->dir->u.index.recordsize;
-		error = ntfs_insert_fixups(buf, io.size);
-		if (error) {
-			printk(KERN_ALERT "NTFS: ntfs_index_writeback() caught "
-					"corrupt index record ntfs record "
-					"header. Refusing to write corrupt "
-					"data to disk. Unmount and run chkdsk "
-					"immediately!\n");
-			return -EIO;
-		}
-		error = ntfs_write_attr(walk->dir, vol->at_index_allocation,
-				I30, (__s64)block << vol->cluster_size_bits,
-				&io);
-		if (error || (io.size != walk->dir->u.index.recordsize &&
-				(error = -EIO, 1)))
-			return error;
-	}
-	return 0;
-}
-
-static int ntfs_split_record(ntfs_iterate_s *walk, char *start, int bsize,
-			     int usize)
-{
-	char *entry, *prev;
-	ntfs_u8 *newbuf = 0, *middle = 0;
-	int error, othersize, mlen;
-	ntfs_io io;
-	ntfs_volume *vol = walk->dir->vol;
-	int oldblock;
-
-	error = ntfs_allocate_index_block(walk);
-	if (error)
-		return error;
-	/* This should not happen. */
-	if (walk->block == -1) {
-		ntfs_error("Trying to split root");
-		return -EOPNOTSUPP;
-	}
-	entry = start + NTFS_GETU16(start + 0x18) + 0x18; 
-	for (prev = entry; entry - start < usize / 2; 
-					       entry += NTFS_GETU16(entry + 8))
-		prev = entry;
-	newbuf = ntfs_malloc(vol->index_record_size);
-	if (!newbuf)
-		return -ENOMEM;
-	io.fn_put = ntfs_put;
-	io.fn_get = ntfs_get;
-	io.param = newbuf;
-	io.size = vol->index_record_size;
-	/* Read in old header. FIXME: Reading everything is overkill. */
-	error = ntfs_read_attr(walk->dir, vol->at_index_allocation, I30,
-			(__s64)walk->newblock << vol->cluster_size_bits, &io);
-	if (error)
-		goto out;
-	if (io.size != vol->index_record_size) {
-		error = -EIO;
-		goto out;
-	}
-	/* FIXME: Adjust header. */
-	/* Copy everything from entry to new block. */
-	othersize = usize - (entry - start);
-	ntfs_memcpy(newbuf + NTFS_GETU16(newbuf + 0x18) + 0x18, entry,
-								    othersize);
-	/* Copy flags. */
-	NTFS_PUTU32(newbuf + 0x24, NTFS_GETU32(start + 0x24));
-	error = ntfs_index_writeback(walk, newbuf, walk->newblock,
-				othersize + NTFS_GETU16(newbuf + 0x18) + 0x18);
-	if (error)
-		goto out;
-	/* Move prev to walk. */
-	mlen = NTFS_GETU16(prev + 0x8);
-	/* Remember old child node. */
-	if (ntfs_entry_has_subnodes(prev))
-		oldblock = NTFS_GETU32(prev + mlen - 8);
-	else
-		oldblock = -1;
-	/* Allow for pointer to subnode. */
-	middle = ntfs_malloc(ntfs_entry_has_subnodes(prev) ? mlen : mlen + 8);
-	if (!middle){
-		error = -ENOMEM;
-		goto out;
-	}
-	ntfs_memcpy(middle, prev, mlen);
-	/* Set has_subnodes flag. */
-	NTFS_PUTU8(middle + 0xC, NTFS_GETU8(middle + 0xC) | 1);
-	/* Middle entry points to block, parent entry will point to newblock. */
-	NTFS_PUTU64(middle + mlen - 8, walk->block);
-	if (walk->new_entry)
-		ntfs_error("Entry not reset");
-	walk->new_entry = middle;
-	walk->u.flags |= ITERATE_SPLIT_DONE;
-	/* Terminate old block. */
-	othersize = usize - (prev-start);
-	NTFS_PUTU64(prev, 0);
-	if (oldblock == -1) {
-		NTFS_PUTU32(prev + 8, 0x10);
-		NTFS_PUTU32(prev + 0xC, 2);
-		othersize += 0x10;
-	} else {
-		NTFS_PUTU32(prev + 8, 0x18);
-		NTFS_PUTU32(prev + 0xC, 3);
-		NTFS_PUTU64(prev + 0x10, oldblock);
-		othersize += 0x18;
-	}
-	/* Write back original block. */
-	error = ntfs_index_writeback(walk, start, walk->block, othersize);
- out:
-	if (newbuf)
-		ntfs_free(newbuf);
-	if (middle)
-		ntfs_free(middle);
-	return error;
-}
-
-static int ntfs_dir_insert(ntfs_iterate_s *walk, char *start, char* entry)
-{
-	int blocksize, usedsize, error, offset;
-	int do_split = 0;
-	offset = entry - start;
-	if (walk->block == -1) { /* index root */
-		blocksize = walk->dir->vol->mft_record_size;
-		usedsize = NTFS_GETU16(start + 0x14) + 0x10;
-	} else {
-		blocksize = walk->dir->u.index.recordsize;
-		usedsize = NTFS_GETU16(start + 0x1C) + 0x18;
-	}
-	if (usedsize + walk->new_entry_size > blocksize) {
-		char* s1 = ntfs_malloc(blocksize + walk->new_entry_size);
-		if (!s1)
-			return -ENOMEM;
-		ntfs_memcpy(s1, start, usedsize);
-		do_split = 1;
-		/* Adjust entry to s1. */
-		entry = s1 + (entry - start);
-		start = s1;
-	}
-	ntfs_memmove(entry + walk->new_entry_size, entry, usedsize - offset);
-	ntfs_memcpy(entry, walk->new_entry, walk->new_entry_size);
-	usedsize += walk->new_entry_size;
-	ntfs_free(walk->new_entry);
-	walk->new_entry = 0;
-	if (do_split) {
-		error = ntfs_split_record(walk, start, blocksize, usedsize);
-		ntfs_free(start);
-	} else {
-		error = ntfs_index_writeback(walk, start, walk->block,usedsize);
-		if (error)
-			return error;
+	/*
+	 * We have finished with this index without success. Check for the
+	 * presence of a child node.
+	 */
+	if (!(ie->_IEH(flags) & INDEX_ENTRY_NODE)) {
+		/* No child node, return -ENOENT. */
+		err = -ENOENT;
+		goto put_unm_err_out;
+	} /* Child node present, descend into it. */
+	/* Consistency check: Verify that an index allocation exists. */
+	if (!NInoIndexAllocPresent(dir_ni)) {
+		ntfs_error(sb, "No index allocation attribute but index entry "
+				"requires one. Directory inode 0x%Lx is "
+				"corrupt or driver bug.",
+				(unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto put_unm_err_out;
 	}
-	return 0;
-}
-
-/* Try to split INDEX_ROOT attributes. Return -E2BIG if nothing changed. */
-int ntfs_split_indexroot(ntfs_inode *ino)
-{
-	ntfs_attribute *ra;
-	ntfs_u8 *root = 0, *index = 0;
-	ntfs_io io;
-	int error, off, i, bsize, isize;
-	ntfs_iterate_s walk;
-
-	ra = ntfs_find_attr(ino, ino->vol->at_index_root, I30);
-	if (!ra)
-		return -ENOTDIR;
-	bsize = ino->vol->mft_record_size;
-	root = ntfs_malloc(bsize);
-	if (!root)
-		return -E2BIG;
-	io.fn_put = ntfs_put;
-	io.param = root;
-	io.size = bsize;
-	error = ntfs_read_attr(ino, ino->vol->at_index_root, I30, 0, &io);
-	if (error)
-		goto out;
-	off = 0x20;
-	/* Count number of entries. */
-	for (i = 0; ntfs_entry_is_used(root + off); i++)
-		off += NTFS_GETU16(root + off + 8);
-	if (i <= 2) {
-		/* We don't split small index roots. */
-		error = -E2BIG;
-		goto out;
+	/* Get the starting vcn of the index_block holding the child node. */
+	vcn = sle64_to_cpup((u8*)ie + le16_to_cpu(ie->_IEH(length)) - 8);
+	ia_mapping = VFS_I(dir_ni)->i_mapping;
+descend_into_child_node:
+	/*
+	 * Convert vcn to index into the index allocation attribute in units
+	 * of PAGE_CACHE_SIZE and map the page cache page, reading it from
+	 * disk if necessary.
+	 */
+	page = ntfs_map_page(ia_mapping, vcn << dir_ni->_IDM(index_vcn_size_bits)
+			>> PAGE_CACHE_SHIFT);
+	if (IS_ERR(page)) {
+		ntfs_error(sb, "Failed to map directory index page, error %ld.",
+				-PTR_ERR(page));
+		goto put_unm_err_out;
+	}
+	kaddr = (u8*)page_address(page);
+fast_descend_into_child_node:
+	/* Get to the index allocation block. */
+	ia = (INDEX_ALLOCATION*)(kaddr + ((vcn << dir_ni->_IDM(index_vcn_size_bits)) &
+			~PAGE_CACHE_MASK));
+	/* Bounds checks. */
+	if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) {
+		ntfs_error(sb, "Out of bounds check failed. Corrupt directory "
+				"inode 0x%Lx or driver bug.",
+				(unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto unm_unm_err_out;
+	}
+	if (sle64_to_cpu(ia->index_block_vcn) != vcn) {
+		ntfs_error(sb, "Actual VCN (0x%Lx) of index buffer is "
+				"different from expected VCN (0x%Lx). "
+				"Directory inode 0x%Lx is corrupt or driver "
+				"bug.",
+				(long long)sle64_to_cpu(ia->index_block_vcn),
+				(long long)vcn,
+				(unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto unm_unm_err_out;
+	}
+	if (le32_to_cpu(ia->index.allocated_size) + 0x18 !=
+			dir_ni->_IDM(index_block_size)) {
+		ntfs_error(sb, "Index buffer (VCN 0x%Lx) of directory inode "
+				"0x%Lx has a size (%u) differing from the "
+				"directory specified size (%u). Directory "
+				"inode is corrupt or driver bug.",
+				(long long)vcn,
+				(unsigned long long)dir_ni->mft_no,
+				le32_to_cpu(ia->index.allocated_size) + 0x18,
+				dir_ni->_IDM(index_block_size));
+		err = -EIO;
+		goto unm_unm_err_out;
+	}
+	index_end = (u8*)ia + dir_ni->_IDM(index_block_size);
+	if (index_end > kaddr + PAGE_CACHE_SIZE) {
+		ntfs_error(sb, "Index buffer (VCN 0x%Lx) of directory inode "
+				"0x%Lx crosses page boundary. Impossible! "
+				"Cannot access! This is probably a bug in the "
+				"driver.", (long long)vcn,
+				(unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto unm_unm_err_out;
+	}
+	index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
+	if (index_end > (u8*)ia + dir_ni->_IDM(index_block_size)) {
+		ntfs_error(sb, "Size of index buffer (VCN 0x%Lx) of directory "
+				"inode 0x%Lx exceeds maximum size.",
+				(long long)vcn,
+				(unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto unm_unm_err_out;
 	}
-	index = ntfs_malloc(ino->vol->index_record_size);
-	if (!index) {
-		error = -ENOMEM;
-		goto out;
+	/* The first index entry. */
+	ie = (INDEX_ENTRY*)((u8*)&ia->index +
+			le32_to_cpu(ia->index.entries_offset));
+	/*
+	 * Iterate similar to above big loop but applied to index buffer, thus
+	 * loop until we exceed valid memory (corruption case) or until we
+	 * reach the last entry.
+	 */
+	for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->_IEH(length)))) {
+		/* Bounds check. */
+		if ((u8*)ie < (u8*)ia || (u8*)ie +
+				sizeof(INDEX_ENTRY_HEADER) > index_end ||
+				(u8*)ie + le16_to_cpu(ie->_IEH(key_length)) >
+				index_end) {
+			ntfs_error(sb, "Index entry out of bounds in "
+					"directory inode 0x%Lx.",
+					(unsigned long long)dir_ni->mft_no);
+			err = -EIO;
+			goto unm_unm_err_out;
 		}
-	walk.dir = ino;
-	walk.block = -1;
-	walk.result = walk.new_entry = 0;
-	walk.name = 0;
-	error = ntfs_allocate_index_block(&walk);
-	if (error)
-		goto out;
-	/* Write old root to new index block. */
-	io.param = index;
-	io.size = ino->vol->index_record_size;
-	error = ntfs_read_attr(ino, ino->vol->at_index_allocation, I30,
-		(__s64)walk.newblock << ino->vol->cluster_size_bits, &io);
-	if (error)
-		goto out;
-	isize = NTFS_GETU16(root + 0x18) - 0x10;
-	ntfs_memcpy(index + NTFS_GETU16(index + 0x18) + 0x18, root+0x20, isize);
-	/* Copy flags. */
-	NTFS_PUTU32(index + 0x24, NTFS_GETU32(root + 0x1C));
-	error = ntfs_index_writeback(&walk, index, walk.newblock, 
-				     isize + NTFS_GETU16(index + 0x18) + 0x18);
-	if (error)
-		goto out;
-	/* Mark root as split. */
-	NTFS_PUTU32(root + 0x1C, 1);
-	/* Truncate index root. */
-	NTFS_PUTU64(root + 0x20, 0);
-	NTFS_PUTU32(root + 0x28, 0x18);
-	NTFS_PUTU32(root + 0x2C, 3);
-	NTFS_PUTU64(root + 0x30, walk.newblock);
-	error = ntfs_index_writeback(&walk, root, -1, 0x38);
- out:
-	ntfs_free(root);
-	ntfs_free(index);
-	return error;
-}
-
-/* The entry has been found. Copy the result in the caller's buffer */
-static int ntfs_copyresult(char *dest, char *source)
-{
-	int length = NTFS_GETU16(source + 8);
-	ntfs_memcpy(dest, source, length);
-	return 1;
-}
-
-/* Use $UpCase some day. */
-static inline unsigned short ntfs_my_toupper(ntfs_volume *vol, ntfs_u16 x)
-{
-	/* We should read any pending rest of $UpCase here. */
-	if (x >= vol->upcase_length)
-		return x;
-	return vol->upcase[x];
-}
-
-/* Everything passed in walk and entry. */
-static int ntfs_my_strcmp(ntfs_iterate_s *walk, const unsigned char *entry)
-{
-	int lu = *(entry + 0x50);
-	int i;
-
-	ntfs_u16* name = (ntfs_u16*)(entry + 0x52);
-	ntfs_volume *vol = walk->dir->vol;
-	for (i = 0; i < lu && i < walk->namelen; i++)
-		if (ntfs_my_toupper(vol, NTFS_GETU16(name + i)) != 
-			     ntfs_my_toupper(vol, NTFS_GETU16(walk->name + i)))
+		/*
+		 * The last entry cannot contain a name. It can however contain
+		 * a pointer to a child node in the B+tree so we just break out.
+		 */
+		if (ie->_IEH(flags) & INDEX_ENTRY_END)
 			break;
-	if (i == lu && i == walk->namelen)
-		return 0;
-	if (i == lu)
-		return 1;
-	if (i == walk->namelen)
-		return -1;
-	if (ntfs_my_toupper(vol, NTFS_GETU16(name + i)) < 
-			    ntfs_my_toupper(vol, NTFS_GETU16(walk->name + i)))
-		return 1;
-	return -1;
-}
-
-/* Necessary forward declaration. */
-static int ntfs_getdir_iterate(ntfs_iterate_s *walk, char *start, char *entry);
-
-/* Parse a block of entries. Load the block, fix it up, and iterate over the
- * entries. The block is given as virtual cluster number. */
-static int ntfs_getdir_record(ntfs_iterate_s *walk, int block)
-{
-	int length = walk->dir->u.index.recordsize;
-	char *record = (char*)ntfs_malloc(length);
-	char *offset;
-	int retval,error;
-	int oldblock;
-	ntfs_io io;
-
-	if (!record)
-		return -ENOMEM;
-	io.fn_put = ntfs_put;
-	io.param = record;
-	io.size = length;
-	/* Read the block from the index allocation attribute. */
-	error = ntfs_read_attr(walk->dir, walk->dir->vol->at_index_allocation,
-		I30, (__s64)block << walk->dir->vol->cluster_size_bits, &io);
-	if (error || io.size != length) {
-		ntfs_error("read failed\n");
-		ntfs_free(record);
-		return 0;
+		/*
+		 * If the current entry has a name type of POSIX, the name is
+		 * case sensitive and not otherwise. This has the effect of us
+		 * not being able to access any POSIX file names which collate
+		 * after the non-POSIX one when they only differ in case, but
+		 * anyone doing screwy stuff like that deserves to burn in
+		 * hell... Doing that kind of stuff on NT4 actually causes
+		 * corruption on the partition even when using SP6a and Linux
+		 * is not involved at all.
+		 */
+		ic = ie->key.file_name.file_name_type ? IGNORE_CASE :
+				CASE_SENSITIVE;
+		/*
+		 * If the names match perfectly, we are done and return the
+		 * mft reference of the inode (i.e. the inode number together
+		 * with the sequence number for consistency checking. We
+		 * convert it to cpu format before returning.
+		 */
+		if (ntfs_are_names_equal(uname, uname_len,
+				(uchar_t*)&ie->key.file_name.file_name,
+				ie->key.file_name.file_name_length, ic,
+				vol->upcase, vol->upcase_len)) {
+found_it2:
+			mref = le64_to_cpu(ie->_IIF(indexed_file));
+			ntfs_unmap_page(page);
+			put_attr_search_ctx(ctx);
+			unmap_mft_record(READ, dir_ni);
+			return mref;
 		}
-	if (!ntfs_check_index_record(walk->dir, record)) {
-		ntfs_error("%x is not an index record\n", block);
-		ntfs_free(record);
-		return 0;
+		/*
+		 * Not a perfect match, need to do full blown collation so we
+		 * know which way in the B+tree we have to go.
+		 */
+		rc = ntfs_collate_names(uname, uname_len,
+				(uchar_t*)&ie->key.file_name.file_name,
+				ie->key.file_name.file_name_length, 1,
+				IGNORE_CASE, vol->upcase, vol->upcase_len);
+		/*
+		 * If uname collates before the name of the current entry, there
+		 * is definitely no such name in this index but we might need to
+		 * descend into the B+tree so we just break out of the loop.
+		 */
+		if (rc == -1)
+			break;
+		/* The names are not equal, continue the search. */
+		if (rc)
+			continue;
+		/*
+		 * Names match with case insensitive comparison, now try the
+		 * case sensitive comparison, which is required for proper
+		 * collation.
+		 */
+		rc = ntfs_collate_names(uname, uname_len,
+				(uchar_t*)&ie->key.file_name.file_name,
+				ie->key.file_name.file_name_length, 1,
+				CASE_SENSITIVE, vol->upcase, vol->upcase_len);
+		if (rc == -1)
+			break;
+		if (rc)
+			continue;
+		/*
+		 * Perfect match, this will never happen as the
+		 * ntfs_are_names_equal() call will have gotten a match but we
+		 * still treat it correctly.
+		 */
+		goto found_it2;
 	}
-	offset = record + NTFS_GETU16(record + 0x18) + 0x18;
-	oldblock = walk->block;
-	walk->block = block;
-	retval = ntfs_getdir_iterate(walk, record, offset);
-	walk->block = oldblock;
-	ntfs_free(record);
-	return retval;
+	/*
+	 * We have finished with this index buffer without success. Check for
+	 * the presence of a child node.
+	 */
+	if (ie->_IEH(flags) & INDEX_ENTRY_NODE) {
+		if ((ia->index.flags & NODE_MASK) == LEAF_NODE) {
+			ntfs_error(sb, "Index entry with child node found in "
+					"a leaf node in directory inode 0x%Lx.",
+					(unsigned long long)dir_ni->mft_no);
+			err = -EIO;
+			goto unm_unm_err_out;
+		}
+		/* Child node present, descend into it. */
+		old_vcn = vcn;
+		vcn = sle64_to_cpup((u8*)ie + le16_to_cpu(ie->_IEH(length)) - 8);
+		if (vcn >= 0) {
+			/* If vcn is in the same page cache page as old_vcn we
+			 * recycle the mapped page. */
+			if (old_vcn << vol->cluster_size_bits >>
+					PAGE_CACHE_SHIFT == vcn <<
+					vol->cluster_size_bits >>
+					PAGE_CACHE_SHIFT)
+				goto fast_descend_into_child_node;
+			ntfs_unmap_page(page);
+			goto descend_into_child_node;
+		}
+		ntfs_error(sb, "Negative child node vcn in directory inode "
+				"0x%Lx.", (unsigned long long)dir_ni->mft_no);
+		err = -EIO;
+		goto unm_unm_err_out;
+	}
+	/* No child node, return -ENOENT. */
+	ntfs_debug("Entry not found.");
+	err = -ENOENT;
+unm_unm_err_out:
+	ntfs_unmap_page(page);
+put_unm_err_out:
+	put_attr_search_ctx(ctx);
+unm_err_out:
+	unmap_mft_record(READ, dir_ni);
+	return ERR_MREF(err);
+map_err_out:
+	ntfs_error(sb, "map_mft_record(READ) failed with error code %ld.",
+			-PTR_ERR(m));
+	return ERR_MREF(PTR_ERR(m));
+dir_err_out:
+	ntfs_error(sb, "Corrupt directory. Aborting lookup.");
+	err = -EIO;
+	goto put_unm_err_out;
 }
 
-/* Go down to the next block of entries. These collate before the current
- * entry. */
-static int ntfs_descend(ntfs_iterate_s *walk, ntfs_u8 *start, ntfs_u8 *entry)
+typedef union {
+	INDEX_ROOT *ir;
+	INDEX_ALLOCATION *ia;
+} index_union __attribute__ ((__transparent_union__));
+
+typedef enum {
+	INDEX_TYPE_ROOT,	/* index root */
+	INDEX_TYPE_ALLOCATION,	/* index allocation */
+} INDEX_TYPE;
+
+/**
+ * ntfs_filldir - ntfs specific filldir method
+ * @vol:	current ntfs volume
+ * @filp:	open file descriptor for the current directory
+ * @ndir:	ntfs inode of current directory
+ * @index_type:	specifies whether @iu is an index root or an index allocation
+ * @iu:		index root or index allocation attribute to which @ie belongs
+ * @ie:		current index entry
+ * @name:	buffer to use for the converted name
+ * @dirent:	vfs filldir callback context
+ * filldir:	vfs filldir callback
+ *
+ * Convert the Unicode name to the loaded NLS and pass it to
+ * the filldir callback.
+ */
+static inline int ntfs_filldir(ntfs_volume *vol, struct file *filp,
+		ntfs_inode *ndir, const INDEX_TYPE index_type,
+		index_union iu, INDEX_ENTRY *ie, u8 *name,
+		void *dirent, filldir_t filldir)
 {
-	int length = NTFS_GETU16(entry + 8);
-	int nextblock = NTFS_GETU32(entry + length - 8);
-	int error;
-
-	if (!ntfs_entry_has_subnodes(entry)) {
-		ntfs_error("illegal ntfs_descend call\n");
+	int name_len;
+	unsigned dt_type;
+	FILE_NAME_TYPE_FLAGS name_type;
+	READDIR_OPTIONS readdir_opts;
+
+	/* Advance the position even if going to skip the entry. */
+	if (index_type == INDEX_TYPE_ALLOCATION)
+		filp->f_pos = (u8*)ie - (u8*)iu.ia +
+				(sle64_to_cpu(iu.ia->index_block_vcn) <<
+				ndir->_IDM(index_vcn_size_bits)) +
+				vol->mft_record_size;
+	else /* if (index_type == INDEX_TYPE_ROOT) */
+		filp->f_pos = (u8*)ie - (u8*)iu.ir;
+	readdir_opts = vol->readdir_opts;
+	name_type = ie->key.file_name.file_name_type;
+	if (name_type == FILE_NAME_DOS && RHideDosNames(readdir_opts)) {
+		ntfs_debug("Skipping DOS name space entry.");
 		return 0;
 	}
-	error = ntfs_getdir_record(walk, nextblock);
-	if (!error && walk->type == DIR_INSERT && 
-	    (walk->u.flags & ITERATE_SPLIT_DONE)) {
-		/* Split has occurred. Adjust entry, insert new_entry. */
-		NTFS_PUTU32(entry + length - 8, walk->newblock);
-		/* Reset flags, as the current block might be split again. */
-		walk->u.flags &= ~ITERATE_SPLIT_DONE;
-		error = ntfs_dir_insert(walk, start, entry);
-	}
-	return error;
-}
-
-static int ntfs_getdir_iterate_byposition(ntfs_iterate_s *walk, char* start,
-					  char *entry)
-{
-	int retval = 0;
-	int curpos = 0, destpos = 0;
-	int length;
-	if (walk->u.pos != 0) {
-		if (ntfs_is_top(walk->u.pos))
+	if (RHideLongNames(readdir_opts)) {
+		if (name_type == FILE_NAME_WIN32 ||
+				name_type == FILE_NAME_POSIX) {
+			ntfs_debug("Skipping WIN32/POSIX name space entry.");
 			return 0;
-		destpos = ntfs_pop(&walk->u.pos);
-	}
-	while (1) {
-		if (walk->u.pos == 0) {
-			if (ntfs_entry_has_subnodes(entry))
-				ntfs_descend(walk, start, entry);
-			else
-				walk->u.pos = ntfs_top();
-			if (ntfs_is_top(walk->u.pos) && 
-			    !ntfs_entry_is_used(entry))
-				return 1;
-			walk->u.pos = ntfs_push(walk->u.pos, curpos);
-			return 1;
 		}
-		if (curpos == destpos) {
-			if (!ntfs_is_top(walk->u.pos) && 
-			    ntfs_entry_has_subnodes(entry)) {
-				retval = ntfs_descend(walk, start, entry);
-				if (retval) {
-					walk->u.pos = ntfs_push(walk->u.pos,
-								curpos);
-					return retval;
 	}
-				if (!ntfs_entry_is_used(entry))
+	if (MREF_LE(ie->_IIF(indexed_file)) == FILE_root) {
+		ntfs_debug("Skipping root directory self reference entry.");
 		return 0;
-				walk->u.pos = 0;
 	}
-			if (ntfs_entry_is_used(entry)) {
-				retval = ntfs_copyresult(walk->result, entry);
-				walk->u.pos = 0;
-			} else {
-				walk->u.pos = ntfs_top();
+	if (MREF_LE(ie->_IIF(indexed_file)) < FILE_first_user &&
+			RHideSystemFiles(readdir_opts)) {
+		ntfs_debug("Skipping system file.");
 		return 0;
 	}
-		}
-		curpos++;
-		if (!ntfs_entry_is_used(entry))
-			break;
-		length = NTFS_GETU16(entry + 8);
-		if (!length) {
-			ntfs_error("infinite loop\n");
-			break;
-		}
-		entry += length;
-	}
-	return -1;
-}
-	
-/* Iterate over a list of entries, either from an index block, or from the
- * index root.
- * If searching BY_POSITION, pop the top index from the position. If the
- * position stack is empty then, return the item at the index and set the
- * position to the next entry. If the position stack is not empty, 
- * recursively proceed for subnodes. If the entry at the position is the
- * 'end of dir' entry, return 'not found' and the empty stack.
- * If searching BY_NAME, walk through the items until found or until
- * one item is collated after the requested item. In the former case, return
- * the result. In the latter case, recursively proceed to the subnodes.
- * If 'end of dir' is reached, the name is not in the directory */
-static int ntfs_getdir_iterate(ntfs_iterate_s *walk, char *start, char *entry)
-{
-	int length;
-	int cmp;
-
-	if (walk->type == BY_POSITION)
-		return ntfs_getdir_iterate_byposition(walk, start, entry);
-	do {
-		/* If the current entry is a real one, compare with the
-		 * requested item. If the current entry is the last item, it
-		 * is always larger than the requested item. */
-		cmp = ntfs_entry_is_used(entry) ? 
-						ntfs_my_strcmp(walk,entry) : -1;
-		switch (walk->type) {
-		case BY_NAME:
-			switch (cmp) {
-			case -1:
-				return ntfs_entry_has_subnodes(entry) ?
-					ntfs_descend(walk, start, entry) : 0;
-			case  0:
-				return ntfs_copyresult(walk->result, entry);
-			case  1:
-				break;
-			}
-			break;
-		case DIR_INSERT:
-			switch (cmp) {
-			case -1:
-				return ntfs_entry_has_subnodes(entry) ?
-					ntfs_descend(walk, start, entry) :
-					ntfs_dir_insert(walk, start, entry);
-			case  0:
-				return -EEXIST;
-			case  1:
-				break;
-			}
-			break;
-		default:
-			ntfs_error("TODO\n"); /* FIXME: ? */
-		}
-		if (!ntfs_entry_is_used(entry))
-			break;
-		length = NTFS_GETU16(entry + 8);
-		if (!length) {
-			ntfs_error("infinite loop\n");
-			break;
-		}
-		entry += length;
-	} while (1);
-	return 0;
-}
-
-/*  Tree walking is done using position numbers. The following numbers have a
- *  special meaning:
- *       0   start (.)
- *      -1   no more entries
- *      -2   ..
- *  All other numbers encode sequences of indices. The sequence a, b, c is 
- *  encoded as <stop><c><b><a>, where <foo> is the encoding of foo. The
- *  first few integers are encoded as follows:
- *      0:    0000    1:    0010    2:    0100    3:    0110
- *      4:    1000    5:    1010    6:    1100 stop:    1110
- *      7:  000001    8:  000101    9:  001001   10:  001101
- *  The least significant bits give the width of this encoding, the other bits
- *  encode the value, starting from the first value of the interval.
- *   tag     width  first value  last value
- *   0       3      0            6
- *   01      4      7            22
- *   011     5      23           54
- *   0111    6      55           119
- *   More values are hopefully not needed, as the file position has currently
- *   64 bits in total. */
-
-/* Find an entry in the directory. Return 0 if not found, otherwise copy the
- * entry to the result buffer. */
-int ntfs_getdir(ntfs_iterate_s *walk)
-{
-	int length = walk->dir->vol->mft_record_size;
-	int retval, error;
-	/* Start at the index root. */
-	char *root = ntfs_malloc(length);
-	ntfs_io io;
-
-	if (!root)
-		return -ENOMEM;
-	io.fn_put = ntfs_put;
-	io.param = root;
-	io.size = length;
-	error = ntfs_read_attr(walk->dir, walk->dir->vol->at_index_root, I30,
-			       0, &io);
-	if (error) {
-		ntfs_error("Not a directory\n");
+	name_len = ntfs_ucstonls(vol, (uchar_t*)&ie->key.file_name.file_name,
+			ie->key.file_name.file_name_length, &name,
+			NTFS_MAX_NAME_LEN * 3 + 1);
+	if (name_len <= 0) {
+		ntfs_debug("Skipping unrepresentable file.");
 		return 0;
 	}
-	walk->block = -1;
-	/* FIXME: Move these to walk. */
-	walk->dir->u.index.recordsize = NTFS_GETU32(root + 0x8);
-	walk->dir->u.index.clusters_per_record = NTFS_GETU32(root + 0xC);
-	/* FIXME: Consistency check. */
-	/* Skip header. */
-	retval = ntfs_getdir_iterate(walk, root, root + 0x20);
-	ntfs_free(root);
-	return retval;
-}
-
-/* Find an entry in the directory by its position stack. Iteration starts
- * if the stack is 0, in which case the position is set to the first item
- * in the directory. If the position is nonzero, return the item at the
- * position and change the position to the next item. The position is -1
- * if there are no more items. */
-int ntfs_getdir_byposition(ntfs_iterate_s *walk)
-{
-	walk->type = BY_POSITION;
-	return ntfs_getdir(walk);
-}
-
-/* Find an entry in the directory by its name. Return 0 if not found. */
-int ntfs_getdir_byname(ntfs_iterate_s *walk)
-{
-	walk->type = BY_NAME;
-	return ntfs_getdir(walk);
+	if (ie->key.file_name.file_attributes &
+			FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT)
+		dt_type = DT_DIR;
+	else
+		dt_type = DT_REG;
+	ntfs_debug("Calling filldir for %s with len %i, f_pos 0x%Lx, inode "
+			"0x%Lx, DT_%s.", name, name_len, filp->f_pos,
+			(unsigned long long)MREF_LE(ie->_IIF(indexed_file)),
+			dt_type == DT_DIR ? "DIR" : "REG");
+	return filldir(dirent, name, name_len, filp->f_pos,
+			(unsigned long)MREF_LE(ie->_IIF(indexed_file)), dt_type);
 }
 
-int ntfs_getdir_unsorted(ntfs_inode *ino, u32 *p_high, u32 *p_low,
-		int (*cb)(ntfs_u8 *, void *), void *param)
+/*
+ * VFS calls readdir with BKL held so no possible RACE conditions.
+ * We use the same basic approach as the old NTFS driver, i.e. we parse the
+ * index root entries and then the index allocation entries that are marked
+ * as in use in the index bitmap.
+ * While this will return the names in random order this doesn't matter for
+ * readdir but OTOH results in faster readdir.
+ */
+static int ntfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 {
-	s64 ib_ofs;
-	char *buf = 0, *entry = 0;
-	ntfs_attribute *attr;
-	ntfs_volume *vol;
-	int byte, bit, err = 0;
-	u32 start, finish, ibs, max_size;
-	ntfs_io io;
-	u8 ibs_bits;
+	s64 ia_pos, ia_start, prev_ia_pos;
+	struct inode *vdir = filp->f_dentry->d_inode;
+	struct super_block *sb = vdir->i_sb;
+	ntfs_inode *ndir = NTFS_I(vdir);
+	ntfs_volume *vol = NTFS_SB(sb);
+	MFT_RECORD *m;
+	INDEX_ROOT *ir;
+	INDEX_ENTRY *ie;
+	INDEX_ALLOCATION *ia;
+	u8 *name;
+	int rc, err, ir_pos, bmp_pos;
+	struct address_space *ia_mapping;
+	struct page *page;
+	u8 *kaddr, *bmp, *index_end;
+	attr_search_context *ctx;
+
+	ntfs_debug("Entering for inode 0x%Lx, f_pos 0x%Lx.",
+			(unsigned long long)ndir->mft_no, filp->f_pos);
+	rc = err = 0;
+	/* Are we at end of dir yet? */
+	if (filp->f_pos >= vdir->i_size + vol->mft_record_size)
+		goto done;
+	/* Emulate . and .. for all directories. */
+	if (!filp->f_pos) {
+		ntfs_debug("Calling filldir for . with len 1, f_pos 0x0, "
+				"inode 0x%Lx, DT_DIR.",
+				(unsigned long long)ndir->mft_no);
+		rc = filldir(dirent, ".", 1, filp->f_pos, vdir->i_ino, DT_DIR);
+		if (rc)
+			goto done;
+		filp->f_pos++;
+	}
+	if (filp->f_pos == 1) {
+		ntfs_debug("Calling filldir for .. with len 2, f_pos 0x1, "
+				"inode 0x%Lx, DT_DIR.",
+				(unsigned long long)NTFS_I(
+				filp->f_dentry->d_parent->d_inode)->mft_no);
+		rc = filldir(dirent, "..", 2, filp->f_pos,
+				filp->f_dentry->d_parent->d_inode->i_ino,
+				DT_DIR);
+		if (rc)
+			goto done;
+		filp->f_pos++;
+	}
+	/* Get hold of the mft record for the directory. */
+	m = map_mft_record(READ, ndir);
+	if (IS_ERR(m)) {
+		err = PTR_ERR(m);
+		goto err_out;
+	}
+
+	err = get_attr_search_ctx(&ctx, ndir, m);
+	if (err)
+		goto unm_err_out;
 
-	if (!ino) {
-		ntfs_error(__FUNCTION__ "(): No inode! Returning -EINVAL.\n");
-		return -EINVAL;
-	}
-	vol = ino->vol;
-	if (!vol) {
-		ntfs_error(__FUNCTION__ "(): Inode 0x%lx has no volume. "
-				"Returning -EINVAL.\n", ino->i_number);
-		return -EINVAL;
-	}
-	ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 1: Entering for "
-			"inode 0x%lx, p_high = 0x%x, p_low = 0x%x.\n",
-			ino->i_number, *p_high, *p_low);
-	if (!*p_high) {
-		/* We are still in the index root. */
-		buf = ntfs_malloc(io.size = vol->mft_record_size);
-		if (!buf)
-			return -ENOMEM;
-		io.fn_put = ntfs_put;
-		io.param = buf;
-		err = ntfs_read_attr(ino, vol->at_index_root, I30, 0, &io);
-		if (err || !io.size)
-			goto read_err_ret;
-		ino->u.index.recordsize = ibs = NTFS_GETU32(buf + 0x8);
-		ino->u.index.clusters_per_record = NTFS_GETU32(buf + 0xC);
-		entry = buf + 0x20;
-		ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 2: In index "
-				"root.\n");
-		ibs_bits = ffs(ibs) - 1;
-		/* Compensate for faked "." and "..". */
-		start = 2;
-	} else { /* We are in an index record. */
-		io.size = ibs = ino->u.index.recordsize;
-		buf = ntfs_malloc(ibs);
-		if (!buf)
-			return -ENOMEM;
-		ibs_bits = ffs(ibs) - 1;
-		io.fn_put = ntfs_put;
-		io.param = buf;
 	/*
-		 * 0 is index root, index allocation starts at 1 and works in
-		 * units of index block size (ibs).
+	 * Allocate a buffer to store the current name being processed
+	 * converted to format determined by current NLS.
 	 */
-		ib_ofs = (s64)(*p_high - 1) << ibs_bits;
-		err = ntfs_read_attr(ino, vol->at_index_allocation, I30, ib_ofs,
-				&io);
-		if (err || io.size != ibs)
-			goto read_err_ret;
-		if (!ntfs_check_index_record(ino, buf)) {
-			ntfs_error(__FUNCTION__ "(): Index block 0x%x is not "
-					"an index record. Returning "
-					"-ENOTDIR.\n", *p_high - 1);
-			ntfs_free(buf);
-			return -ENOTDIR;
-		}
-		entry = buf + 0x18 + NTFS_GETU16(buf + 0x18);
-		ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 3: In index "
-				"allocation.\n");
-		start = 0;
-	}
-	/* Process the entries. */
-	finish = *p_low;
-	for (; entry < (buf + ibs) && ntfs_entry_is_used(entry);
-			entry += NTFS_GETU16(entry + 8)) {
-		if (start < finish) {
-			/* Skip entries that were already processed. */
-			ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 4: "
-					"Skipping already processed entry "
-					"p_high 0x%x, p_low 0x%x.\n", *p_high,
-					start);
-			start++;
+	name = (u8*)kmalloc(NTFS_MAX_NAME_LEN * 3 + 1, GFP_NOFS);
+	if (!name) {
+		err = -ENOMEM;
+		goto put_unm_err_out;
+	}
+	/* Are we jumping straight into the index allocation attribute? */
+	if (filp->f_pos >= vol->mft_record_size)
+		goto skip_index_root;
+	/* Get the offset into the index root attribute. */
+	ir_pos = (s64)filp->f_pos;
+	/* Find the index root attribute in the mft record. */
+	if (!lookup_attr(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, 0,
+			ctx)) {
+		ntfs_error(sb, "Index root attribute missing in directory "
+				"inode 0x%Lx.",
+				(unsigned long long)ndir->mft_no);
+		err = -EIO;
+		goto kf_unm_err_out;
+	}
+	/* Get to the index root value (it's been verified in read_inode). */
+	ir = (INDEX_ROOT*)((u8*)ctx->attr +
+			le16_to_cpu(ctx->attr->_ARA(value_offset)));
+	index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
+	/* The first index entry. */
+	ie = (INDEX_ENTRY*)((u8*)&ir->index +
+			le32_to_cpu(ir->index.entries_offset));
+	/*
+	 * Loop until we exceed valid memory (corruption case) or until we
+	 * reach the last entry or until filldir tells us it has had enough
+	 * or signals an error (both covered by the rc test).
+	 */
+	for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->_IEH(length)))) {
+		ntfs_debug("In index root, offset 0x%x.", (u8*)ie - (u8*)ir);
+		/* Bounds checks. */
+		if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie +
+				sizeof(INDEX_ENTRY_HEADER) > index_end ||
+				(u8*)ie + le16_to_cpu(ie->_IEH(key_length)) >
+				index_end)
+			goto dir_err_out;
+		/* The last entry cannot contain a name. */
+		if (ie->_IEH(flags) & INDEX_ENTRY_END)
+			break;
+		/* Skip index root entry if continuing previous readdir. */
+		if (ir_pos > (u8*)ie - (u8*)ir)
 			continue;
+		/* Submit the name to the filldir callback. */
+		rc = ntfs_filldir(vol, filp, ndir, INDEX_TYPE_ROOT, ir, ie,
+				name, dirent, filldir);
+		if (rc)
+			goto abort;
+	}
+	/* If there is no index allocation attribute we are finished. */
+	if (!NInoIndexAllocPresent(ndir))
+		goto EOD;
+	/* Advance f_pos to the beginning of the index allocation. */
+	filp->f_pos = vol->mft_record_size;
+	/* Reinitialize the search context. */
+	reinit_attr_search_ctx(ctx);
+skip_index_root:
+	if (NInoBmpNonResident(ndir)) {
+		/*
+		 * Read the page of the bitmap that contains the current index
+		 * block.
+		 */
+		// TODO: FIXME: Implement this!
+		ntfs_error(sb, "Index bitmap is non-resident, which is not "
+				"supported yet. Pretending that end of "
+				"directory has been reached.\n");
+		goto EOD;
+	} else {
+		/* Find the index bitmap attribute in the mft record. */
+		if (!lookup_attr(AT_BITMAP, I30, 4, CASE_SENSITIVE, 0, NULL, 0,
+				ctx)) {
+			ntfs_error(sb, "Index bitmap attribute missing in "
+					"directory inode 0x%Lx.",
+					(unsigned long long)ndir->mft_no);
+			err = -EIO;
+			goto kf_unm_err_out;
+		}
+		bmp = (u8*)ctx->attr + le16_to_cpu(ctx->attr->_ARA(value_offset));
+	}
+	/* Get the offset into the index allocation attribute. */
+	ia_pos = (s64)filp->f_pos - vol->mft_record_size;
+	ia_mapping = vdir->i_mapping;
+	/* If the index block is not in use find the next one that is. */
+	bmp_pos = ia_pos >> ndir->_IDM(index_block_size_bits);
+	page = NULL;
+	kaddr = NULL;
+	prev_ia_pos = -1LL;
+	if (bmp_pos >> 3 >= ndir->_IDM(bmp_size)) {
+		ntfs_error(sb, "Current index allocation position exceeds "
+				"index bitmap size.");
+		goto kf_unm_err_out;
+	}
+	while (!(bmp[bmp_pos >> 3] & (1 << (bmp_pos & 7)))) {
+find_next_index_buffer:
+		bmp_pos++;
+		/* If we have reached the end of the bitmap, we are done. */
+		if (bmp_pos >> 3 >= ndir->_IDM(bmp_size))
+			goto EOD;
+		ia_pos = (s64)bmp_pos << ndir->_IDM(index_block_size_bits);
+	}
+	ntfs_debug("Handling index buffer 0x%x.", bmp_pos);
+	/* If the current index buffer is in the same page we reuse the page. */
+	if ((prev_ia_pos & PAGE_CACHE_MASK) != (ia_pos & PAGE_CACHE_MASK)) {
+		prev_ia_pos = ia_pos;
+		if (page)
+			ntfs_unmap_page(page);
+		/*
+		 * Map the page cache page containing the current ia_pos,
+		 * reading it from disk if necessary.
+		 */
+		page = ntfs_map_page(ia_mapping, ia_pos >> PAGE_CACHE_SHIFT);
+		if (IS_ERR(page))
+			goto map_page_err_out;
+		kaddr = (u8*)page_address(page);
+	}
+	/* Get the current index buffer. */
+	ia = (INDEX_ALLOCATION*)(kaddr + (ia_pos & ~PAGE_CACHE_MASK &
+			~(s64)(ndir->_IDM(index_block_size) - 1)));
+	/* Bounds checks. */
+	if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) {
+		ntfs_error(sb, "Out of bounds check failed. Corrupt directory "
+				"inode 0x%Lx or driver bug.",
+				(unsigned long long)ndir->mft_no);
+		err = -EIO;
+		goto unm_dir_err_out;
+	}
+	if (sle64_to_cpu(ia->index_block_vcn) != (ia_pos &
+			~(s64)(ndir->_IDM(index_block_size) - 1)) >>
+			ndir->_IDM(index_vcn_size_bits)) {
+		ntfs_error(sb, "Actual VCN (0x%Lx) of index buffer is "
+				"different from expected VCN (0x%Lx). "
+				"Directory inode 0x%Lx is corrupt or driver "
+				"bug. ",
+				(long long)sle64_to_cpu(ia->index_block_vcn),
+				(long long)ia_pos >> ndir->_IDM(index_vcn_size_bits),
+				(unsigned long long)ndir->mft_no);
+		err = -EIO;
+		goto unm_dir_err_out;
+	}
+	if (le32_to_cpu(ia->index.allocated_size) + 0x18 !=
+			ndir->_IDM(index_block_size)) {
+		ntfs_error(sb, "Index buffer (VCN 0x%Lx) of directory inode "
+				"0x%Lx has a size (%u) differing from the "
+				"directory specified size (%u). Directory "
+				"inode is corrupt or driver bug.",
+				(long long)ia_pos >> ndir->_IDM(index_vcn_size_bits),
+				(unsigned long long)ndir->mft_no,
+				le32_to_cpu(ia->index.allocated_size) + 0x18,
+				ndir->_IDM(index_block_size));
+		err = -EIO;
+		goto unm_dir_err_out;
+	}
+	index_end = (u8*)ia + ndir->_IDM(index_block_size);
+	if (index_end > kaddr + PAGE_CACHE_SIZE) {
+		ntfs_error(sb, "Index buffer (VCN 0x%Lx) of directory inode "
+				"0x%Lx crosses page boundary. Impossible! "
+				"Cannot access! This is probably a bug in the "
+				"driver.", (long long)ia_pos >>
+				ndir->_IDM(index_vcn_size_bits),
+				(unsigned long long)ndir->mft_no);
+		err = -EIO;
+		goto unm_dir_err_out;
+	}
+	ia_start = ia_pos & ~(s64)(ndir->_IDM(index_block_size) - 1);
+	index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
+	if (index_end > (u8*)ia + ndir->_IDM(index_block_size)) {
+		ntfs_error(sb, "Size of index buffer (VCN 0x%Lx) of directory "
+				"inode 0x%Lx exceeds maximum size.",
+				(long long)ia_pos >> ndir->_IDM(index_vcn_size_bits),
+				(unsigned long long)ndir->mft_no);
+		err = -EIO;
+		goto unm_dir_err_out;
 	}
-		ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 5: "
-				"Processing entry p_high 0x%x, p_low 0x%x.\n",
-				*p_high, *p_low);
-		if ((err = cb(entry, param))) {
-			/* filldir signalled us to stop. */
-			ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): "
-					"Unsorted 6: cb returned %i, "
-					"returning 0, p_high 0x%x, p_low 0x%x."
-					"\n", *p_high, *p_low);
-			ntfs_free(buf);
-			return 0;
-		}
-		++*p_low;
-	}
-	ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 7: After processing "
-			"entries, p_high 0x%x, p_low 0x%x.\n", *p_high, *p_low);
-	/* We have to locate the next record. */
-	ntfs_free(buf);
-	buf = 0;
-	*p_low = 0;
-	attr = ntfs_find_attr(ino, vol->at_bitmap, I30);
-	if (!attr) {
-		/* Directory does not have index bitmap and index allocation. */
-		*p_high = 0x7fff;
-		ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 8: No index "
-				"allocation. Returning 0, p_high 0x7fff, "
-				"p_low 0x0.\n");
-		return 0;
-	}
-	max_size = attr->size;
-	if (max_size > 0x7fff >> 3) {
-		ntfs_error(__FUNCTION__ "(): Directory too large. Visible "
-				"length is truncated.\n");
-		max_size = 0x7fff >> 3;
-	}
-	buf = ntfs_malloc(max_size);
-	if (!buf)
-		return -ENOMEM;
-	io.param = buf;
-	io.size = max_size;
-	err = ntfs_read_attr(ino, vol->at_bitmap, I30, 0, &io);
-	if (err || io.size != max_size)
-		goto read_err_ret;
-	attr = ntfs_find_attr(ino, vol->at_index_allocation, I30);
-	if (!attr) {
-		ntfs_free(buf);
-		ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 9: Find "
-				"attr failed. Returning -EIO.\n");
-		return -EIO;
-	}
-	if (attr->resident) {
-		ntfs_free(buf);
-		ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 9.5: IA is "
-				"resident. Not allowed. Returning EINVAL.\n");
-		return -EINVAL;
-	}
-	/* Loop while going through non-allocated index records. */
-	max_size <<= 3;
-	while (1) {
-		if (++*p_high >= 0x7fff) {
-			ntfs_error(__FUNCTION__ "(): Unsorted 10: Directory "
-					"inode 0x%lx overflowed the maximum "
-					"number of index allocation buffers "
-					"the driver can cope with. Pretending "
-					"to be at end of directory.\n",
-					ino->i_number);
-			goto fake_eod;
-		}
-		if (*p_high > max_size || (s64)*p_high << ibs_bits >
-				attr->initialized) {
-fake_eod:
-			/* No more index records. */
-			*p_high = 0x7fff;
-			*p_low = 0;
-			ntfs_free(buf);
-			ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted "
-					"10.5: No more index records. "
-					"Returning 0, p_high 0x7fff, p_low "
-					"0.\n");
-			return 0;
-		}
-		byte = (ntfs_cluster_t)(*p_high - 1);
-		bit = 1 << (byte & 7);
-		byte >>= 3;
-		if ((buf[byte] & bit))
+	/* The first index entry in this index buffer. */
+	ie = (INDEX_ENTRY*)((u8*)&ia->index +
+			le32_to_cpu(ia->index.entries_offset));
+	/*
+	 * Loop until we exceed valid memory (corruption case) or until we
+	 * reach the last entry or until filldir tells us it has had enough
+	 * or signals an error (both covered by the rc test).
+	 */
+	for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->_IEH(length)))) {
+		ntfs_debug("In index allocation, offset 0x%Lx.",
+				(long long)ia_start + ((u8*)ie - (u8*)ia));
+		/* Bounds checks. */
+		if ((u8*)ie < (u8*)ia || (u8*)ie +
+				sizeof(INDEX_ENTRY_HEADER) > index_end ||
+				(u8*)ie + le16_to_cpu(ie->_IEH(key_length)) >
+				index_end)
+			goto unm_dir_err_out;
+		/* The last entry cannot contain a name. */
+		if (ie->_IEH(flags) & INDEX_ENTRY_END)
 			break;
-	};
-	ntfs_debug(DEBUG_DIR3, __FUNCTION__ "(): Unsorted 11: Done. "
-			"Returning 0, p_high 0x%x, p_low 0x%x.\n", *p_high,
-			*p_low);
-	ntfs_free(buf);
+		/* Skip index block entry if continuing previous readdir. */
+		if (ia_pos - ia_start > (u8*)ie - (u8*)ia)
+			continue;
+		/* Submit the name to the filldir callback. */
+		rc = ntfs_filldir(vol, filp, ndir, INDEX_TYPE_ALLOCATION, ia,
+				ie, name, dirent, filldir);
+		if (rc) {
+			ntfs_unmap_page(page);
+			goto abort;
+		}
+	}
+	goto find_next_index_buffer;
+EOD:
+	/* We are finished, set f_pos to EOD. */
+	filp->f_pos = vdir->i_size + vol->mft_record_size;
+abort:
+	put_attr_search_ctx(ctx);
+	unmap_mft_record(READ, ndir);
+	kfree(name);
+done:
+#ifdef DEBUG
+	if (!rc)
+		ntfs_debug("EOD, f_pos 0x%Lx, returning 0.", filp->f_pos);
+	else
+		ntfs_debug("filldir returned %i, f_pos 0x%Lx, returning 0.",
+				rc, filp->f_pos);
+#endif
 	return 0;
-read_err_ret:
-	if (!err)
-		err = -EIO;
-	ntfs_error(__FUNCTION__ "(): Read failed. Returning error code %i.\n",
-			err);
-	ntfs_free(buf);
+map_page_err_out:
+	ntfs_error(sb, "Reading index allocation data failed.");
+	err = PTR_ERR(page);
+kf_unm_err_out:
+	kfree(name);
+put_unm_err_out:
+	put_attr_search_ctx(ctx);
+unm_err_out:
+	unmap_mft_record(READ, ndir);
+err_out:
+	ntfs_debug("Failed. Returning error code %i.", -err);
 	return err;
+unm_dir_err_out:
+	ntfs_unmap_page(page);
+dir_err_out:
+	ntfs_error(sb, "Corrupt directory. Aborting. You should run chkdsk.");
+	err = -EIO;
+	goto kf_unm_err_out;
 }
 
-int ntfs_dir_add(ntfs_inode *dir, ntfs_inode *new, ntfs_attribute *name)
-{
-	ntfs_iterate_s walk;
-	int nsize, esize;
-	ntfs_u8* entry, *ndata;
-	int error;
-
-	walk.type = DIR_INSERT;
-	walk.dir = dir;
-	walk.u.flags = 0;
-	nsize = name->size;
-	ndata = name->d.data;
-	walk.name = (ntfs_u16*)(ndata + 0x42);
-	walk.namelen = NTFS_GETU8(ndata + 0x40);
-	walk.new_entry_size = esize = (nsize + 0x10 + 7) & ~7;
-	walk.new_entry = entry = ntfs_malloc(esize);
-	if (!entry)
-		return -ENOMEM;
-	NTFS_PUTINUM(entry, new);
-	NTFS_PUTU16(entry + 0x8, esize); /* Size of entry. */
-	NTFS_PUTU16(entry + 0xA, nsize); /* Size of original name attribute. */
-	NTFS_PUTU16(entry + 0xC, 0);     /* Flags. */
-	NTFS_PUTU16(entry + 0xE, 0);	 /* Reserved. */
-	ntfs_memcpy(entry + 0x10, ndata, nsize);
-	ntfs_bzero(entry + 0x10 + nsize, esize - 0x10 - nsize);
-	error = ntfs_getdir(&walk);
-	if (walk.new_entry)
-		ntfs_free(walk.new_entry);
-	return error;
-}
+struct file_operations ntfs_dir_ops = {
+	read:			generic_read_dir,	/* Return -EISDIR. */
+	readdir:		ntfs_readdir,		/* Read directory. */
+};
 
 #if 0
-int ntfs_dir_add1(ntfs_inode *dir, const char* name, int namelen,
-		  ntfs_inode *ino)
-{
-	ntfs_iterate_s walk;
-	int error;
-	int nsize;
-	char *entry;
-	ntfs_attribute *name_attr;
-	error = ntfs_decodeuni(dir->vol, name, namelen, &walk.name,
-			       &walk.namelen);
-	if (error)
-		return error;
-	/* FIXME: Set flags. */
-	walk.type = DIR_INSERT;
-	walk.dir = dir;
-	/* walk.new = ino; */
-	/* Prepare new entry. */
-	/* Round up to a multiple of 8. */
-	walk.new_entry_size = nsize = ((0x52 + 2 * walk.namelen + 7) / 8) * 8;
-	walk.new_entry = entry = ntfs_malloc(nsize);
-	if (!entry)
-		return -ENOMEM;
-	ntfs_bzero(entry, nsize);
-	NTFS_PUTINUM(entry, ino);
-	NTFS_PUTU16(entry + 8, nsize);
-	NTFS_PUTU16(entry + 0xA, 0x42 + 2 * namelen); /* FIXME: Size of name 
-						       * attribute. */
-	NTFS_PUTU32(entry + 0xC, 0); /* FIXME: D-F? */
-	name_attr = ntfs_find_attr(ino, vol->at_file_name, 0);
-						    /* FIXME: multiple names */
-	if (!name_attr || !name_attr->resident)
-		return -EIDRM;
-	/* Directory, file stamps, sizes, filename. */
-	ntfs_memcpy(entry + 0x10, name_attr->d.data, 0x42 + 2 * namelen);
-	error = ntfs_getdir(&walk);
-	ntfs_free(walk.name);
-	return error;
-}
+/* NOTE: write, poll, fsync, readv, writev can be called without the big
+ * kernel lock held in all filesystems. */
+struct file_operations {
+	loff_t (*llseek) (struct file *, loff_t, int);
+	ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
+	unsigned int (*poll) (struct file *, struct poll_table_struct *);
+	int (*ioctl) (struct inode *, struct file *, unsigned int,
+			unsigned long);
+	int (*mmap) (struct file *, struct vm_area_struct *);
+	int (*open) (struct inode *, struct file *);
+	int (*flush) (struct file *);
+	int (*release) (struct inode *, struct file *);
+	int (*fsync) (struct file *, struct dentry *, int datasync);
+	int (*fasync) (int, struct file *, int);
+	int (*lock) (struct file *, int, struct file_lock *);
+	ssize_t (*readv) (struct file *, const struct iovec *, unsigned long,
+			loff_t *);
+	ssize_t (*writev) (struct file *, const struct iovec *, unsigned long,
+			loff_t *);
+	ssize_t (*sendpage) (struct file *, struct page *, int, size_t,
+			loff_t *, int);
+	unsigned long (*get_unmapped_area)(struct file *, unsigned long,
+			unsigned long, unsigned long, unsigned long);
+};
 #endif
 
-/* Fills out and creates an INDEX_ROOT attribute. */
-int ntfs_add_index_root(ntfs_inode *ino, int type)
-{
-	ntfs_attribute *da;
-	ntfs_u8 data[0x30]; /* 0x20 header, 0x10 last entry. */
-	char name[10];
-
-	NTFS_PUTU32(data, type);
-	/* Collation rule. 1 == COLLATION_FILENAME */
-	NTFS_PUTU32(data + 4, 1);
-	NTFS_PUTU32(data + 8, ino->vol->index_record_size);
-	NTFS_PUTU32(data + 0xC, ino->vol->index_clusters_per_record);
-	/* Byte offset to first INDEX_ENTRY. */
-	NTFS_PUTU32(data + 0x10, 0x10);
-	/* Size of entries, including header. */
-	NTFS_PUTU32(data + 0x14, 0x20);
-	NTFS_PUTU32(data + 0x18, 0x20);
-	/* No index allocation, yet. */
-	NTFS_PUTU32(data + 0x1C, 0);
-	/* Add last entry. */
-	/* Indexed MFT record. */
-	NTFS_PUTU64(data + 0x20, 0);
-	/* Size of entry. */
-	NTFS_PUTU32(data + 0x28, 0x10);
-	/* Flags: Last entry, no child nodes. */
-	NTFS_PUTU32(data + 0x2C, 2);
-	/* Compute name. */
-	ntfs_indexname(name, type);
-	return ntfs_create_attr(ino, ino->vol->at_index_root, name,
-				data, sizeof(data), &da);
-}
-
-int ntfs_mkdir(ntfs_inode *dir, const char *name, int namelen,
-	       ntfs_inode *result)
-{
-	int error;
-	
-	error = ntfs_alloc_inode(dir, result, name, namelen, NTFS_AFLAG_DIR);
-	if (error)
-		goto out;
-	error = ntfs_add_index_root(result, 0x30);
-	if (error)
-		goto out;
-	/* Set directory bit. */
-	result->attr[0x16] |= 2;
-	error = ntfs_update_inode(dir);
-	if (error)
-		goto out;
-	error = ntfs_update_inode(result);
-	if (error)
-		goto out;
- out:
-	return error;
-}
-

fs/ntfs/dir.h

-/*
- * dir.h - Header file for dir.c
- *
- * Copyright (C) 1997 Rgis Duchesne
- */
-#define ITERATE_SPLIT_DONE      1
-
-enum ntfs_iterate_e {
-    BY_POSITION,
-    BY_NAME,
-    DIR_INSERT
-};
-
-/* not all fields are used for all operations */
-typedef struct ntfs_iterate_s {
-	enum ntfs_iterate_e type;
-	ntfs_inode *dir;
-	union{
-		ntfs_u64 pos;
-		int flags;
-	}u;
-	char *result;      /* pointer to entry if found */
-	ntfs_u16* name;
-	int namelen;
-	int block;         /* current index record */
-	int newblock;      /* index record created in a split */
-	char *new_entry;
-	int new_entry_size;
-	/*ntfs_inode* new;*/
-} ntfs_iterate_s;
-
-int ntfs_getdir_unsorted(ntfs_inode *ino, ntfs_u32 *p_high, ntfs_u32* p_low,
-			 int (*cb)(ntfs_u8*, void*), void *param);
-
-int ntfs_getdir_byname(ntfs_iterate_s *walk);
-
-int ntfs_dir_add(ntfs_inode *dir, ntfs_inode *new, ntfs_attribute *name);
-
-int ntfs_check_index_record(ntfs_inode *ino, char *record);
-
-int ntfs_getdir_byposition(ntfs_iterate_s *walk);
-
-int ntfs_mkdir(ntfs_inode* dir,const char* name,int namelen, ntfs_inode *ino);
-
-int ntfs_split_indexroot(ntfs_inode *ino);
-
-int ntfs_add_index_root(ntfs_inode *ino, int type);
-

fs/ntfs/endian.h

+/*
+ * endian.h - Defines for endianness handling in NTFS Linux kernel driver.
+ *	      Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_ENDIAN_H
+#define _LINUX_NTFS_ENDIAN_H
+
+#include <asm/byteorder.h>
+
+/*
+ * Signed endianness conversion defines.
+ */
+#define sle16_to_cpu(x)		((s16)__le16_to_cpu((s16)(x)))
+#define sle32_to_cpu(x)		((s32)__le32_to_cpu((s32)(x)))
+#define sle64_to_cpu(x)		((s64)__le64_to_cpu((s64)(x)))
+
+#define sle16_to_cpup(x)	((s16)__le16_to_cpu(*(s16*)(x)))
+#define sle32_to_cpup(x)	((s32)__le32_to_cpu(*(s32*)(x)))
+#define sle64_to_cpup(x)	((s64)__le64_to_cpu(*(s64*)(x)))
+
+#define cpu_to_sle16(x)		((s16)__cpu_to_le16((s16)(x)))
+#define cpu_to_sle32(x)		((s32)__cpu_to_le32((s32)(x)))
+#define cpu_to_sle64(x)		((s64)__cpu_to_le64((s64)(x)))
+
+#define cpu_to_sle16p(x)	((s16)__cpu_to_le16(*(s16*)(x)))
+#define cpu_to_sle32p(x)	((s32)__cpu_to_le32(*(s32*)(x)))
+#define cpu_to_sle64p(x)	((s64)__cpu_to_le64(*(s64*)(x)))
+
+#endif /* _LINUX_NTFS_ENDIAN_H */
+

fs/ntfs/file.c

+/*
+ * file.c - NTFS kernel file operations. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "ntfs.h"
+
+struct file_operations ntfs_file_ops = {
+	llseek:			generic_file_llseek,	/* Seek inside file. */
+	read:			generic_file_read,	/* Read from file. */
+	write:			NULL,			/* . */
+	readdir:		NULL,			/* . */
+	poll:			NULL,			/* . */
+	ioctl:			NULL,			/* . */
+	mmap:			generic_file_mmap,	/* Mmap file. */
+	open:			generic_file_open,	/* Open file. */
+	flush:			NULL,			/* . */
+	release:		NULL,			/* . */
+	fsync:			NULL,			/* . */
+	fasync:			NULL,			/* . */
+	lock:			NULL,			/* . */
+	readv:			NULL,			/* . */
+	writev:			NULL,			/* . */
+	sendpage:		NULL,			/* . */
+	get_unmapped_area:	NULL,			/* . */
+};
+
+struct inode_operations ntfs_file_inode_ops = {
+	create:		NULL,		/* . */
+	lookup:		NULL,		/* . */
+	link:		NULL,		/* . */
+	unlink:		NULL,		/* . */
+	symlink:	NULL,		/* . */
+	mkdir:		NULL,		/* . */
+	rmdir:		NULL,		/* . */
+	mknod:		NULL,		/* . */
+	rename:		NULL,		/* . */
+	readlink:	NULL,		/* . */
+	follow_link:	NULL,		/* . */
+	truncate:	NULL,		/* . */
+	permission:	NULL,		/* . */
+	revalidate:	NULL,		/* . */
+	setattr:	NULL,		/* . */
+	getattr:	NULL,		/* . */
+};
+
+#if 0
+/* NOTE: read, write, poll, fsync, readv, writev can be called without the big
+ * kernel lock held in all filesystems. */
+struct file_operations {
+	struct module *owner;
+	loff_t (*llseek) (struct file *, loff_t, int);
+	ssize_t (*read) (struct file *, char *, size_t, loff_t *);
+	ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
+	int (*readdir) (struct file *, void *, filldir_t);
+	unsigned int (*poll) (struct file *, struct poll_table_struct *);
+	int (*ioctl) (struct inode *, struct file *, unsigned int,
+			unsigned long);
+	int (*mmap) (struct file *, struct vm_area_struct *);
+	int (*flush) (struct file *);
+	int (*release) (struct inode *, struct file *);
+	int (*fsync) (struct file *, struct dentry *, int datasync);
+	int (*fasync) (int, struct file *, int);
+	int (*lock) (struct file *, int, struct file_lock *);
+	ssize_t (*readv) (struct file *, const struct iovec *, unsigned long,
+			loff_t *);
+	ssize_t (*writev) (struct file *, const struct iovec *, unsigned long,
+			loff_t *);
+	ssize_t (*sendpage) (struct file *, struct page *, int, size_t,
+			loff_t *, int);
+	unsigned long (*get_unmapped_area)(struct file *, unsigned long,
+			unsigned long, unsigned long, unsigned long);
+};
+
+struct inode_operations {
+	int (*create) (struct inode *,struct dentry *,int);
+	struct dentry * (*lookup) (struct inode *,struct dentry *);
+	int (*link) (struct dentry *,struct inode *,struct dentry *);
+	int (*unlink) (struct inode *,struct dentry *);
+	int (*symlink) (struct inode *,struct dentry *,const char *);
+	int (*mkdir) (struct inode *,struct dentry *,int);
+	int (*rmdir) (struct inode *,struct dentry *);
+	int (*mknod) (struct inode *,struct dentry *,int,int);
+	int (*rename) (struct inode *, struct dentry *,
+			struct inode *, struct dentry *);
+	int (*readlink) (struct dentry *, char *,int);
+	int (*follow_link) (struct dentry *, struct nameidata *);
+	void (*truncate) (struct inode *);
+	int (*permission) (struct inode *, int);
+	int (*revalidate) (struct dentry *);
+	int (*setattr) (struct dentry *, struct iattr *);
+	int (*getattr) (struct dentry *, struct iattr *);
+};
+#endif
+
+struct file_operations ntfs_empty_file_ops = {
+	llseek:			NULL,			/* . */
+	read:			NULL,			/* . */
+	write:			NULL,			/* . */
+	readdir:		NULL,			/* . */
+	poll:			NULL,			/* . */
+	ioctl:			NULL,			/* . */
+	mmap:			NULL,			/* . */
+	open:			NULL,			/* . */
+	flush:			NULL,			/* . */
+	release:		NULL,			/* . */
+	fsync:			NULL,			/* . */
+	fasync:			NULL,			/* . */
+	lock:			NULL,			/* . */
+	readv:			NULL,			/* . */
+	writev:			NULL,			/* . */
+	sendpage:		NULL,			/* . */
+	get_unmapped_area:	NULL,			/* . */
+};
+
+struct inode_operations ntfs_empty_inode_ops = {
+	create:		NULL,		/* . */
+	lookup:		NULL,		/* . */
+	link:		NULL,		/* . */
+	unlink:		NULL,		/* . */
+	symlink:	NULL,		/* . */
+	mkdir:		NULL,		/* . */
+	rmdir:		NULL,		/* . */
+	mknod:		NULL,		/* . */
+	rename:		NULL,		/* . */
+	readlink:	NULL,		/* . */
+	follow_link:	NULL,		/* . */
+	truncate:	NULL,		/* . */
+	permission:	NULL,		/* . */
+	revalidate:	NULL,		/* . */
+	setattr:	NULL,		/* . */
+	getattr:	NULL,		/* . */
+};
+

fs/ntfs/fs.c

-/*
- * fs.c - NTFS driver for Linux 2.4.x
- *
- * Legato Systems, Inc. (http://www.legato.com) have sponsored Anton
- * Altaparmakov to develop NTFS on Linux since June 2001.
- *
- * Copyright (C) 1995-1997, 1999 Martin von Lwis
- * Copyright (C) 1996 Richard Russon
- * Copyright (C) 1996-1997 Rgis Duchesne
- * Copyright (C) 2000-2001, Anton Altaparmakov (AIA)
- */
-
-#include <linux/config.h>
-#include <linux/errno.h>
-#include "ntfstypes.h"
-#include "struct.h"
-#include "util.h"
-#include "inode.h"
-#include "super.h"
-#include "dir.h"
-#include "support.h"
-#include "macros.h"
-#include "sysctl.h"
-#include "attr.h"
-#include <linux/module.h>
-#include <asm/uaccess.h>
-#include <linux/locks.h>
-#include <linux/init.h>
-#include <linux/smp_lock.h>
-#include <linux/blkdev.h>
-#include <asm/page.h>
-#include <linux/nls.h>
-#include <linux/ntfs_fs.h>
-
-/* Forward declarations. */
-static struct inode_operations ntfs_dir_inode_operations;
-static struct file_operations ntfs_dir_operations;
-
-#define ITEM_SIZE 2040
-
-/* Io functions to user space. */
-static void ntfs_putuser(ntfs_io* dest, void *src, ntfs_size_t len)
-{
-	copy_to_user(dest->param, src, len);
-	dest->param += len;
-}
-
-#ifdef CONFIG_NTFS_RW
-struct ntfs_getuser_update_vm_s {
-	const char *user;
-	struct inode *ino;
-	loff_t off;
-};
-
-static void ntfs_getuser_update_vm(void *dest, ntfs_io *src, ntfs_size_t len)
-{
-	struct ntfs_getuser_update_vm_s *p = src->param;
-	
-	copy_from_user(dest, p->user, len);
-	p->user += len;
-	p->off += len;
-}
-#endif
-
-/* loff_t is 64 bit signed, so is cool. */
-static ssize_t ntfs_read(struct file *filp, char *buf, size_t count,loff_t *off)
-{
-	int error;
-	ntfs_io io;
-	ntfs_attribute *attr;
-	ntfs_inode *ino = NTFS_I(filp->f_dentry->d_inode);
-
-	/* Inode is not properly initialized. */
-	if (!ino)
-		return -EINVAL;
-	ntfs_debug(DEBUG_OTHER, "ntfs_read %x, %Lx, %x ->",
-		   (unsigned)ino->i_number, (unsigned long long)*off,
-		   (unsigned)count);
-	attr = ntfs_find_attr(ino, ino->vol->at_data, NULL);
-	/* Inode has no unnamed data attribute. */
-	if (!attr) {
-		ntfs_debug(DEBUG_OTHER, "ntfs_read: $DATA not found!\n");
-		return -EINVAL;
-	}
-	if (attr->flags & ATTR_IS_ENCRYPTED)
-		return -EACCES;
-	/* Read the data. */
-	io.fn_put = ntfs_putuser;
-	io.fn_get = 0;
-	io.param = buf;
-	io.size = count;
-	error = ntfs_read_attr(ino, ino->vol->at_data, NULL, *off, &io);
-	if (error && !io.size) {
-		ntfs_debug(DEBUG_OTHER, "ntfs_read: read_attr failed with "
-				"error %i, io size %u.\n", error, io.size);
-		return error;
-	}
-	*off += io.size;
-	ntfs_debug(DEBUG_OTHER, "ntfs_read: finished. read %u bytes.\n",
-								io.size);
-	return io.size;
-}
-
-#ifdef CONFIG_NTFS_RW
-static ssize_t ntfs_write(struct file *filp, const char *buf, size_t count,
-		loff_t *pos)
-{
-	int err;
-	struct inode *vfs_ino = filp->f_dentry->d_inode;
-	ntfs_inode *ntfs_ino = NTFS_I(vfs_ino);
-	ntfs_attribute *data;
-	ntfs_io io;
-	struct ntfs_getuser_update_vm_s param;
-
-	if (!ntfs_ino)
-		return -EINVAL;
-	ntfs_debug(DEBUG_LINUX, __FUNCTION__ "(): Entering for inode 0x%lx, "
-			"*pos 0x%Lx, count 0x%x.\n", ntfs_ino->i_number, *pos,
-			count);
-	/* Allows to lock fs ro at any time. */
-	if (vfs_ino->i_sb->s_flags & MS_RDONLY)
-		return -EROFS;
-	data = ntfs_find_attr(ntfs_ino, ntfs_ino->vol->at_data, NULL);
-	if (!data)
-		return -EINVAL;
-	/* Evaluating O_APPEND is the file system's job... */
-	if (filp->f_flags & O_APPEND)
-		*pos = vfs_ino->i_size;
-	if (!data->resident && *pos + count > data->allocated) {
-		err = ntfs_extend_attr(ntfs_ino, data, *pos + count);
-		if (err < 0)
-			return err;
-	}
-	param.user = buf;
-	param.ino = vfs_ino;
-	param.off = *pos;
-	io.fn_put = 0;
-	io.fn_get = ntfs_getuser_update_vm;
-	io.param = &param;
-	io.size = count;
-	io.do_read = 0;
-	err = ntfs_readwrite_attr(ntfs_ino, data, *pos, &io);
-	ntfs_debug(DEBUG_LINUX, __FUNCTION__ "(): Returning %i\n", -err);
-	if (!err) {
-		*pos += io.size;
-		if (*pos > vfs_ino->i_size)
-			vfs_ino->i_size = *pos;
-		mark_inode_dirty(vfs_ino);
-		return io.size;
-	}
-	return err;
-}
-#endif
-
-struct ntfs_filldir {
-	struct inode *dir;
-	filldir_t filldir;
-	unsigned int type;
-	u32 ph, pl;
-	void *dirent;
-	char *name;
-	int namelen;
-	int ret_code;
-};
-
-static int ntfs_printcb(ntfs_u8 *entry, void *param)
-{
-	unsigned long inum = NTFS_GETU64(entry) & 0xffffffffffff;
-	struct ntfs_filldir *nf = param;
-	u32 flags = NTFS_GETU32(entry + 0x48);
-	char show_sys_files = 0;
-	u8 name_len = NTFS_GETU8(entry + 0x50);
-	u8 name_type = NTFS_GETU8(entry + 0x51);
-	int err;
-	unsigned file_type;
-
-	switch (nf->type) {
-	case ngt_dos:
-		/* Don't display long names. */
-		if (!(name_type & 2))
-			return 0;
-		break;
-	case ngt_nt:
-		/* Don't display short-only names. */
-		if ((name_type & 3) == 2)
-			return 0;
-		break;
-	case ngt_posix:
-		break;
-	case ngt_full:
-		show_sys_files = 1;
-		break;
-	default:
-		BUG();
-	}
-	err = ntfs_encodeuni(NTFS_INO2VOL(nf->dir), (ntfs_u16*)(entry + 0x52),
-			name_len, &nf->name, &nf->namelen);
-	if (err) {
-		ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Skipping "
-				"unrepresentable file.\n");
-		err = 0;
-		goto err_ret;
-	}
-	if (!show_sys_files && inum < 0x10UL) {
-		ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Skipping system "
-				"file (%s).\n", nf->name);
-		err = 0;
-		goto err_ret;
-	}
-	/* Do not return ".", as this is faked. */
-	if (nf->namelen == 1 && nf->name[0] == '.') {
-		ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Skipping \".\"\n");
-		err = 0;
-		goto err_ret;
-	}
-	nf->name[nf->namelen] = 0;
-	if (flags & 0x10000000) /* FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT */
-		file_type = DT_DIR;
-	else
-		file_type = DT_REG;
-	ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Calling filldir for %s with "
-			"len %i, f_pos 0x%Lx, inode %lu, %s.\n",
-			nf->name, nf->namelen, (loff_t)(nf->ph << 16) | nf->pl,
-			inum, file_type == DT_DIR ? "DT_DIR" : "DT_REG");
-	/*
-	 * Userspace side of filldir expects an off_t rather than an loff_t.
-	 * And it also doesn't like the most significant bit being set as it
-	 * then considers the value to be negative. Thus this implementation
-	 * limits the number of index records to 32766, which should be plenty.
-	 */
-	err = nf->filldir(nf->dirent, nf->name, nf->namelen,
-			(loff_t)(nf->ph << 16) | nf->pl, inum, file_type);
-	if (err)
-		nf->ret_code = err;
-err_ret:
-	nf->namelen = 0;
-	ntfs_free(nf->name);
-	nf->name = NULL;
-	return err;
-}
-
-/*
- * readdir returns '.', then '..', then the directory entries in sequence.
- * As the root directory contains an entry for itself, '.' is not emulated for
- * the root directory.
- */
-static int ntfs_readdir(struct file* filp, void *dirent, filldir_t filldir)
-{
-	struct inode *dir = filp->f_dentry->d_inode;
-	int err;
-	struct ntfs_filldir cb;
-
-	cb.ret_code = 0;
-	cb.pl = filp->f_pos & 0xffff;
-	cb.ph = (filp->f_pos >> 16) & 0x7fff;
-	filp->f_pos = (loff_t)(cb.ph << 16) | cb.pl;
-	ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Entering for inode %lu, "
-			"f_pos 0x%Lx, i_mode 0x%x, i_count %lu.\n", dir->i_ino,
-			filp->f_pos, (unsigned int)dir->i_mode,
-			atomic_read(&dir->i_count));
-	if (!cb.ph) {
-		/* Start of directory. Emulate "." and "..". */
-		if (!cb.pl) {
-			ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Calling "
-				    "filldir for . with len 1, f_pos 0x%Lx, "
-				    "inode %lu, DT_DIR.\n", filp->f_pos,
-				    dir->i_ino);
-			cb.ret_code = filldir(dirent, ".", 1, filp->f_pos,
-				    dir->i_ino, DT_DIR);
-			if (cb.ret_code)
-				goto done;
-			cb.pl++;
-			filp->f_pos = (loff_t)(cb.ph << 16) | cb.pl;
-		}
-		if (cb.pl == (u32)1) {
-			ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Calling "
-				    "filldir for .. with len 2, f_pos 0x%Lx, "
-				    "inode %lu, DT_DIR.\n", filp->f_pos,
-				    parent_ino(filp->f_dentry));
-			cb.ret_code = filldir(dirent, "..", 2, filp->f_pos,
-				    parent_ino(filp->f_dentry), DT_DIR);
-			if (cb.ret_code)
-				goto done;
-			cb.pl++;
-			filp->f_pos = (loff_t)(cb.ph << 16) | cb.pl;
-		}
-	} else if (cb.ph >= 0x7fff)
-		/* End of directory. */
-		goto done;
-	cb.dir = dir;
-	cb.filldir = filldir;
-	cb.dirent = dirent;
-	cb.type = NTFS_INO2VOL(dir)->ngt;
-	do {
-		ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Looking for next "
-				"file using ntfs_getdir_unsorted(), f_pos "
-				"0x%Lx.\n", (loff_t)(cb.ph << 16) | cb.pl);
-		err = ntfs_getdir_unsorted(NTFS_I(dir), &cb.ph, &cb.pl,
-				ntfs_printcb, &cb);
-	} while (!err && !cb.ret_code && cb.ph < 0x7fff);
-	filp->f_pos = (loff_t)(cb.ph << 16) | cb.pl;
-	ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): After ntfs_getdir_unsorted()"
-			" calls, f_pos 0x%Lx.\n", filp->f_pos);
-	if (!err) {
-done:
-#ifdef DEBUG
-		if (!cb.ret_code)
-			ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): EOD, f_pos "
-					"0x%Lx, returning 0.\n", filp->f_pos);
-		else 
-			ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): filldir "
-					"returned %i, returning 0, f_pos "
-					"0x%Lx.\n", cb.ret_code, filp->f_pos);
-#endif
-		return 0;
-	}
-	ntfs_debug(DEBUG_OTHER, __FUNCTION__ "(): Returning %i, f_pos 0x%Lx.\n",
-			err, filp->f_pos);
-	return err;
-}
-
-/* Copied from vfat driver. */
-static int simple_getbool(char *s, int *setval)
-{
-	if (s) {
-		if (!strcmp(s, "1") || !strcmp(s, "yes") || !strcmp(s, "true"))
-			*setval = 1;
-		else if (!strcmp(s, "0") || !strcmp(s, "no") ||
-							!strcmp(s, "false"))
-			*setval = 0;
-		else
-			return 0;
-	} else
-		*setval = 1;
-	return 1;
-}
-
-/*
- * This needs to be outside parse_options() otherwise a remount will reset
- * these unintentionally.
- */
-static void init_ntfs_super_block(ntfs_volume* vol)
-{
-	vol->uid = vol->gid = 0;
-	vol->umask = 0077;
-	vol->ngt = ngt_nt;
-	vol->nls_map = (void*)-1;
-	vol->mft_zone_multiplier = -1;
-}
-
-/* Parse the (re)mount options. */
-static int parse_options(ntfs_volume *vol, char *opt)
-{
-	char *value;		/* Defaults if not specified and !remount. */
-	ntfs_uid_t uid = -1;	/* 0, root user only */
-	ntfs_gid_t gid = -1;	/* 0, root user only */
-	int umask = -1;		/* 0077, owner access only */
-	unsigned int ngt = -1;	/* ngt_nt */
-	void *nls_map = NULL;	/* Try to load the default NLS. */
-	int use_utf8 = -1;	/* If no NLS specified and loading the default
-				   NLS failed use utf8. */
-	int mft_zone_mul = -1;	/* 1 */
-
-	if (!opt)
-		goto done;
-	for (opt = strtok(opt, ","); opt; opt = strtok(NULL, ",")) {
-		if ((value = strchr(opt, '=')) != NULL)
-			*value ++= '\0';
-		if (strcmp(opt, "uid") == 0) {
-			if (!value || !*value)
-				goto needs_arg;
-			uid = simple_strtoul(value, &value, 0);
-			if (*value) {
-				printk(KERN_ERR "NTFS: uid invalid argument\n");
-				return 0;
-			}
-		} else if (strcmp(opt, "gid") == 0) {
-			if (!value || !*value)
-				goto needs_arg;
-			gid = simple_strtoul(value, &value, 0);
-			if (*value) {
-				printk(KERN_ERR "NTFS: gid invalid argument\n");
-				return 0;
-			}
-		} else if (strcmp(opt, "umask") == 0) {
-			if (!value || !*value)
-				goto needs_arg;
-			umask = simple_strtoul(value, &value, 0);
-			if (*value) {
-				printk(KERN_ERR "NTFS: umask invalid "
-						"argument\n");
-				return 0;
-			}
-		} else if (strcmp(opt, "mft_zone_multiplier") == 0) {
-			unsigned long ul;
-
-			if (!value || !*value)
-				goto needs_arg;
-			ul = simple_strtoul(value, &value, 0);
-			if (*value) {
-				printk(KERN_ERR "NTFS: mft_zone_multiplier "
-						"invalid argument\n");
-				return 0;
-			}
-			if (ul >= 1 && ul <= 4)
-				mft_zone_mul = ul;
-			else {
-				mft_zone_mul = 1;
-				printk(KERN_WARNING "NTFS: mft_zone_multiplier "
-					      "out of range. Setting to 1.\n");
-			}
-		} else if (strcmp(opt, "posix") == 0) {
-			int val;
-			if (!value || !*value)
-				goto needs_arg;
-			if (!simple_getbool(value, &val))
-				goto needs_bool;
-			ngt = val ? ngt_posix : ngt_nt;
-		} else if (strcmp(opt, "show_sys_files") == 0) {
-			int val = 0;
-			if (!value || !*value)
-				val = 1;
-			else if (!simple_getbool(value, &val))
-				goto needs_bool;
-			ngt = val ? ngt_full : ngt_nt;
-		} else if (strcmp(opt, "iocharset") == 0) {
-			if (!value || !*value)
-				goto needs_arg;
-			nls_map = load_nls(value);
-			if (!nls_map) {
-				printk(KERN_ERR "NTFS: charset not found");
-				return 0;
-			}
-		} else if (strcmp(opt, "utf8") == 0) {
-			int val = 0;
-			if (!value || !*value)
-				val = 1;
-			else if (!simple_getbool(value, &val))
-				goto needs_bool;
-			use_utf8 = val;
-		} else {
-			printk(KERN_ERR "NTFS: unkown option '%s'\n", opt);
-			return 0;
-		}
-	}
-done:
-	if (use_utf8 == -1) {
-		/* utf8 was not specified at all. */
-		if (!nls_map) {
-			/*
-			 * No NLS was specified. If first mount, load the
-			 * default NLS, otherwise don't change the NLS setting.
-			 */
-			if (vol->nls_map == (void*)-1)
-				vol->nls_map = load_nls_default();
-		} else {
-			/* If an NLS was already loaded, unload it first. */
-			if (vol->nls_map && vol->nls_map != (void*)-1)
-				unload_nls(vol->nls_map);
-			/* Use the specified NLS. */
-			vol->nls_map = nls_map;
-		}
-	} else {
-		/* utf8 was specified. */
-		if (use_utf8 && nls_map) {
-			unload_nls(nls_map);
-			printk(KERN_ERR "NTFS: utf8 cannot be combined with "
-					"iocharset.\n");
-			return 0;
-		}
-		/* If an NLS was already loaded, unload it first. */
-		if (vol->nls_map && vol->nls_map != (void*)-1)
-			unload_nls(vol->nls_map);
-		if (!use_utf8) {
-			/* utf8 was specified as false. */
-			if (!nls_map)
-				/* No NLS was specified, load the default. */
-				vol->nls_map = load_nls_default();
-			else
-				/* Use the specified NLS. */
-				vol->nls_map = nls_map;
-		} else
-			/* utf8 was specified as true. */
-			vol->nls_map = NULL;
-	}
-	if (uid != -1)
-		vol->uid = uid;
-	if (gid != -1)
-		vol->gid = gid;
-	if (umask != -1)
-		vol->umask = (ntmode_t)umask;
-	if (ngt != -1)
-		vol->ngt = ngt;
-	if (mft_zone_mul != -1) {
-		/* mft_zone_multiplier was specified. */
-		if (vol->mft_zone_multiplier != -1) {
-			/* This is a remount, ignore a change and warn user. */
-			if (vol->mft_zone_multiplier != mft_zone_mul)
-				printk(KERN_WARNING "NTFS: Ignoring changes in "
-						"mft_zone_multiplier on "
-						"remount. If you want to "
-						"change this you need to "
-						"umount and mount again.\n");
-		} else
-			/* Use the specified multiplier. */
-			vol->mft_zone_multiplier = mft_zone_mul;
-	} else if (vol->mft_zone_multiplier == -1)
-		/* No multiplier specified and first mount, so set default. */
-		vol->mft_zone_multiplier = 1;
-	return 1;
-needs_arg:
-	printk(KERN_ERR "NTFS: %s needs an argument", opt);
-	return 0;
-needs_bool:
-	printk(KERN_ERR "NTFS: %s needs boolean argument", opt);
-	return 0;
-}
-			
-static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *d)
-{
-	struct inode *res = 0;
-	char *item = 0;
-	ntfs_iterate_s walk;
-	int err;
-	
-	ntfs_debug(DEBUG_NAME1, __FUNCTION__ "(): Looking up %s in directory "
-			"ino 0x%x.\n", d->d_name.name, (unsigned)dir->i_ino);
-	walk.name = NULL;
-	walk.namelen = 0;
-	/* Convert to wide string. */
-	lock_kernel();
-	err = ntfs_decodeuni(NTFS_INO2VOL(dir), (char*)d->d_name.name,
-			       d->d_name.len, &walk.name, &walk.namelen);
-	if (err)
-		goto err_ret;
-	item = ntfs_malloc(ITEM_SIZE);
-	if (!item) {
-		err = -ENOMEM;
-		goto err_ret;
-	}
-	/* ntfs_getdir will place the directory entry into item, and the first
-	 * long long is the MFT record number. */
-	walk.type = BY_NAME;
-	walk.dir = NTFS_I(dir);
-	walk.result = item;
-	if (ntfs_getdir_byname(&walk))
-		res = iget(dir->i_sb, NTFS_GETU32(item));
-	d_add(d, res);
-	ntfs_free(item);
-	ntfs_free(walk.name);
-	unlock_kernel();
-	/* Always return success, the dcache will handle negative entries. */
-	return NULL;
-err_ret:
-	ntfs_free(walk.name);
-	unlock_kernel();
-	return ERR_PTR(err);
-}
-
-static struct file_operations ntfs_file_operations = {
-	llseek:		generic_file_llseek,
-	read:		ntfs_read,
-#ifdef CONFIG_NTFS_RW
-	write:		ntfs_write,
-#endif
-	open:		generic_file_open,
-};
-
-static struct inode_operations ntfs_inode_operations;
-
-#ifdef CONFIG_NTFS_RW
-static int ntfs_create(struct inode* dir, struct dentry *d, int mode)
-{
-	struct inode *r = 0;
-	ntfs_inode *ino = 0;
-	ntfs_volume *vol;
-	int error = 0;
-	ntfs_attribute *si;
-
-	lock_kernel();
-	r = new_inode(dir->i_sb);
-	if (!r) {
-		error = -ENOMEM;
-		goto fail;
-	}
-	ntfs_debug(DEBUG_OTHER, "ntfs_create %s\n", d->d_name.name);
-	vol = NTFS_INO2VOL(dir);
-	ino = NTFS_I(r);
-	ino->u.index.recordsize = 0;
-	ino->u.index.clusters_per_record = 0;
-	error = ntfs_alloc_file(NTFS_I(dir), ino, (char*)d->d_name.name,
-				d->d_name.len);
-	if (error) {
-		ntfs_error("ntfs_alloc_file FAILED: error = %i", error);
-		goto fail;
-	}
-	/* Not doing this one was causing a huge amount of corruption! Now the
-	 * bugger bytes the dust! (-8 (AIA) */
-	r->i_ino = ino->i_number;
-	error = ntfs_update_inode(ino);
-	if (error)
-		goto fail;
-	error = ntfs_update_inode(NTFS_I(dir));
-	if (error)
-		goto fail;
-	r->i_uid = vol->uid;
-	r->i_gid = vol->gid;
-	/* FIXME: dirty? dev? */
-	/* Get the file modification times from the standard information. */
-	si = ntfs_find_attr(ino, vol->at_standard_information, NULL);
-	if (si) {
-		char *attr = si->d.data;
-		r->i_atime = ntfs_ntutc2unixutc(NTFS_GETU64(attr + 0x18));
-		r->i_ctime = ntfs_ntutc2unixutc(NTFS_GETU64(attr));
-		r->i_mtime = ntfs_ntutc2unixutc(NTFS_GETU64(attr + 8));
-	}
-	/* It's not a directory */
-	r->i_op = &ntfs_inode_operations;
-	r->i_fop = &ntfs_file_operations;
-	r->i_mode = S_IFREG | S_IRUGO;
-#ifdef CONFIG_NTFS_RW
-	r->i_mode |= S_IWUGO;
-#endif
-	r->i_mode &= ~vol->umask;
-	unlock_kernel();
-	insert_inode_hash(r);
-	d_instantiate(d, r);
-	return 0;
- fail:
-	unlock_kernel();
-	if (r)
-		iput(r);
-	return error;
-}
-
-static int _linux_ntfs_mkdir(struct inode *dir, struct dentry* d, int mode)
-{
-	int error;
-	struct inode *r = 0;
-	ntfs_volume *vol;
-	ntfs_inode *ino;
-	ntfs_attribute *si;
-
-	lock_kernel();
-	ntfs_debug (DEBUG_DIR1, "mkdir %s in %x\n", d->d_name.name, dir->i_ino);
-	error = -ENAMETOOLONG;
-	if (d->d_name.len > /* FIXME: */ 255)
-		goto out;
-	error = -EIO;
-	r = new_inode(dir->i_sb);
-	if (!r)
-		goto out;
-	vol = NTFS_INO2VOL(dir);
-	ino = NTFS_I(r);
-	error = ntfs_mkdir(NTFS_I(dir), d->d_name.name, d->d_name.len,
-			   ino);
-	if (error)
-		goto out;
-	/* Not doing this one was causing a huge amount of corruption! Now the
-	 * bugger bytes the dust! (-8 (AIA) */
-	r->i_ino = ino->i_number;
-	r->i_uid = vol->uid;
-	r->i_gid = vol->gid;
-	si = ntfs_find_attr(ino, vol->at_standard_information, NULL);
-	if (si) {
-		char *attr = si->d.data;
-		r->i_atime = ntfs_ntutc2unixutc(NTFS_GETU64(attr + 0x18));
-		r->i_ctime = ntfs_ntutc2unixutc(NTFS_GETU64(attr));
-		r->i_mtime = ntfs_ntutc2unixutc(NTFS_GETU64(attr + 8));
-	}
-	/* It's a directory. */
-	r->i_op = &ntfs_dir_inode_operations;
-	r->i_fop = &ntfs_dir_operations;
-	r->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
-#ifdef CONFIG_NTFS_RW
-	r->i_mode |= S_IWUGO;
-#endif
-	r->i_mode &= ~vol->umask;	
-	
-	insert_inode_hash(r);
-	d_instantiate(d, r);
-	error = 0;
- out:
- 	ntfs_debug (DEBUG_DIR1, "mkdir returns %d\n", error);
-	unlock_kernel();
-	return error;
-}
-#endif
-
-static struct file_operations ntfs_dir_operations = {
-	read:		generic_read_dir,
-	readdir:	ntfs_readdir,
-};
-
-static struct inode_operations ntfs_dir_inode_operations = {
-	lookup:		ntfs_lookup,
-#ifdef CONFIG_NTFS_RW
-	create:		ntfs_create,
-	mkdir:		_linux_ntfs_mkdir,
-#endif
-};
-
-/* ntfs_read_inode() is called by the Virtual File System (the kernel layer 
- * that deals with filesystems) when iget is called requesting an inode not
- * already present in the inode table. Typically filesystems have separate
- * inode_operations for directories, files and symlinks. */
-static void ntfs_read_inode(struct inode* inode)
-{
-	ntfs_volume *vol;
-	ntfs_inode *ino;
-	ntfs_attribute *data;
-	ntfs_attribute *si;
-
-	vol = NTFS_INO2VOL(inode);
-	inode->i_mode = 0;
-	ntfs_debug(DEBUG_OTHER, "ntfs_read_inode 0x%lx\n", inode->i_ino);
-	switch (inode->i_ino) {
-		/* Those are loaded special files. */
-	case FILE_Mft:
-		if (!vol->mft_ino || ((vol->ino_flags & 1) == 0))
-			goto sys_file_error;
-		ntfs_memcpy(NTFS_I(inode), vol->mft_ino, sizeof(ntfs_inode));
-		ino = vol->mft_ino;
-		vol->mft_ino = NTFS_I(inode);
-		vol->ino_flags &= ~1;
-		ntfs_free(ino);
-		ino = vol->mft_ino;
-		ntfs_debug(DEBUG_OTHER, "Opening $MFT!\n");
-		break;
-	case FILE_MftMirr:
-		if (!vol->mftmirr || ((vol->ino_flags & 2) == 0))
-			goto sys_file_error;
-		ntfs_memcpy(NTFS_I(inode), vol->mftmirr, sizeof(ntfs_inode));
-		ino = vol->mftmirr;
-		vol->mftmirr = NTFS_I(inode);
-		vol->ino_flags &= ~2;
-		ntfs_free(ino);
-		ino = vol->mftmirr;
-		ntfs_debug(DEBUG_OTHER, "Opening $MFTMirr!\n");
-		break;
-	case FILE_BitMap:
-		if (!vol->bitmap || ((vol->ino_flags & 4) == 0))
-			goto sys_file_error;
-		ntfs_memcpy(NTFS_I(inode), vol->bitmap, sizeof(ntfs_inode));
-		ino = vol->bitmap;
-		vol->bitmap = NTFS_I(inode);
-		vol->ino_flags &= ~4;
-		ntfs_free(ino);
-		ino = vol->bitmap;
-		ntfs_debug(DEBUG_OTHER, "Opening $Bitmap!\n");
-		break;
-	case FILE_LogFile ... FILE_AttrDef:
-	/* No need to log root directory accesses. */
-	case FILE_Boot ... FILE_UpCase:
-		ntfs_debug(DEBUG_OTHER, "Opening system file %i!\n",
-				inode->i_ino);
-	default:
-		ino = NTFS_I(inode);
-		ino->u.index.recordsize = 0;
-		ino->u.index.clusters_per_record = 0;
-		if (ntfs_init_inode(ino, NTFS_INO2VOL(inode), inode->i_ino)) {
-			ntfs_debug(DEBUG_OTHER, "NTFS: Error loading inode "
-					"0x%x\n", (unsigned int)inode->i_ino);
-			return;
-		}
-	}
-	/* Set uid/gid from mount options */
-	inode->i_uid = vol->uid;
-	inode->i_gid = vol->gid;
-	inode->i_nlink = 1;
-	/* Use the size of the data attribute as file size */
-	data = ntfs_find_attr(ino, vol->at_data, NULL);
-	if (!data)
-		inode->i_size = 0;
-	else
-		inode->i_size = data->size;
-	/* Get the file modification times from the standard information. */
-	si = ntfs_find_attr(ino, vol->at_standard_information, NULL);
-	if (si) {
-		char *attr = si->d.data;
-		inode->i_atime = ntfs_ntutc2unixutc(NTFS_GETU64(attr + 0x18));
-		inode->i_ctime = ntfs_ntutc2unixutc(NTFS_GETU64(attr));
-		inode->i_mtime = ntfs_ntutc2unixutc(NTFS_GETU64(attr + 8));
-	}
-	/* If it has an index root, it's a directory. */
-	if (ntfs_find_attr(ino, vol->at_index_root, "$I30")) {
-		ntfs_attribute *at;
-		at = ntfs_find_attr(ino, vol->at_index_allocation, "$I30");
-		inode->i_size = at ? at->size : 0;
-		inode->i_op = &ntfs_dir_inode_operations;
-		inode->i_fop = &ntfs_dir_operations;
-		inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
-	} else {
-		inode->i_op = &ntfs_inode_operations;
-		inode->i_fop = &ntfs_file_operations;
-		inode->i_mode = S_IFREG | S_IRUGO;
-	}
-#ifdef CONFIG_NTFS_RW
-	if (!data || !(data->flags & (ATTR_IS_COMPRESSED | ATTR_IS_ENCRYPTED)))
-		inode->i_mode |= S_IWUGO;
-#endif
-	inode->i_mode &= ~vol->umask;
-	return;
-sys_file_error:
-	ntfs_error("Critical error. Tried to call ntfs_read_inode() before we "
-		"have completed read_super() or VFS error.\n");
-	// FIXME: Should we panic() at this stage?
-}
-
-#ifdef CONFIG_NTFS_RW
-static void ntfs_write_inode(struct inode *ino, int unused)
-{
-	lock_kernel();
-	ntfs_debug(DEBUG_LINUX, "ntfs_write_inode 0x%x\n", ino->i_ino);
-	ntfs_update_inode(NTFS_I(ino));
-	unlock_kernel();
-}
-#endif
-
-static void _ntfs_clear_inode(struct inode *inode)
-{
-	ntfs_inode *ino;
-	ntfs_volume *vol;
-	
-	lock_kernel();
-	ntfs_debug(DEBUG_OTHER, "_ntfs_clear_inode 0x%x\n", inode->i_ino);
-	vol = NTFS_INO2VOL(inode);
-	if (!vol)
-		ntfs_error("_ntfs_clear_inode: vol = NTFS_INO2VOL(inode) is "
-				"NULL.\n");
-	switch (inode->i_ino) {
-	case FILE_Mft:
-		if (vol->mft_ino && ((vol->ino_flags & 1) == 0)) {
-			ino = (ntfs_inode*)ntfs_malloc(sizeof(ntfs_inode));
-			ntfs_memcpy(ino, NTFS_I(inode), sizeof(ntfs_inode));
-			vol->mft_ino = ino;
-			vol->ino_flags |= 1;
-			goto unl_out;
-		}
-		break;
-	case FILE_MftMirr:
-		if (vol->mftmirr && ((vol->ino_flags & 2) == 0)) {
-			ino = (ntfs_inode*)ntfs_malloc(sizeof(ntfs_inode));
-			ntfs_memcpy(ino, NTFS_I(inode), sizeof(ntfs_inode));
-			vol->mftmirr = ino;
-			vol->ino_flags |= 2;
-			goto unl_out;
-		}
-		break;
-	case FILE_BitMap:
-		if (vol->bitmap && ((vol->ino_flags & 4) == 0)) {
-			ino = (ntfs_inode*)ntfs_malloc(sizeof(ntfs_inode));
-			ntfs_memcpy(ino, NTFS_I(inode), sizeof(ntfs_inode));
-			vol->bitmap = ino;
-			vol->ino_flags |= 4;
-			goto unl_out;
-		}
-		break;
-	default:
-		/* Nothing. Just clear the inode and exit. */
-	}
-	ntfs_clear_inode(NTFS_I(inode));
-unl_out:
-	unlock_kernel();
-	return;
-}
-
-/* Called when umounting a filesystem by do_umount() in fs/super.c. */
-static void ntfs_put_super(struct super_block *sb)
-{
-	ntfs_volume *vol;
-
-	ntfs_debug(DEBUG_OTHER, "ntfs_put_super\n");
-	vol = NTFS_SB2VOL(sb);
-	ntfs_release_volume(vol);
-	if (vol->nls_map)
-		unload_nls(vol->nls_map);
-	ntfs_debug(DEBUG_OTHER, "ntfs_put_super: done\n");
-}
-
-/* Called by the kernel when asking for stats. */
-static int ntfs_statfs(struct super_block *sb, struct statfs *sf)
-{
-	struct inode *mft;
-	ntfs_volume *vol;
-	__s64 size;
-	int error;
-
-	ntfs_debug(DEBUG_OTHER, "ntfs_statfs\n");
-	vol = NTFS_SB2VOL(sb);
-	sf->f_type = NTFS_SUPER_MAGIC;
-	sf->f_bsize = vol->cluster_size;
-	error = ntfs_get_volumesize(NTFS_SB2VOL(sb), &size);
-	if (error)
-		return error;
-	sf->f_blocks = size;	/* Volumesize is in clusters. */
-	size = (__s64)ntfs_get_free_cluster_count(vol->bitmap);
-	/* Just say zero if the call failed. */
-	if (size < 0LL)
-		size = 0;
-	sf->f_bfree = sf->f_bavail = size;
-	ntfs_debug(DEBUG_OTHER, "ntfs_statfs: calling mft = iget(sb, "
-			"FILE_Mft)\n");
-	mft = iget(sb, FILE_Mft);
-	ntfs_debug(DEBUG_OTHER, "ntfs_statfs: iget(sb, FILE_Mft) returned "
-			"0x%x\n", mft);
-	if (!mft)
-		return -EIO;
-	sf->f_files = mft->i_size >> vol->mft_record_size_bits;
-	ntfs_debug(DEBUG_OTHER, "ntfs_statfs: calling iput(mft)\n");
-	iput(mft);
-	/* Should be read from volume. */
-	sf->f_namelen = 255;
-	return 0;
-}
-
-/* Called when remounting a filesystem by do_remount_sb() in fs/super.c. */
-static int ntfs_remount_fs(struct super_block *sb, int *flags, char *options)
-{
-	if (!parse_options(NTFS_SB2VOL(sb), options))
-		return -EINVAL;
-	return 0;
-}
-
-/* Define the super block operation that are implemented */
-
-static kmem_cache_t * ntfs_inode_cachep;
-
-static struct inode *__ntfs_alloc_inode(struct super_block *sb)
-{
-	struct ntfs_i *ei;
-	ei = (struct ntfs_i *)kmem_cache_alloc(ntfs_inode_cachep, SLAB_KERNEL);
-	if (!ei)
-		return NULL;
-	return &ei->vfs_inode;
-}
-
-static void ntfs_destroy_inode(struct inode *inode)
-{
-	kmem_cache_free(ntfs_inode_cachep, ntfs_i(inode));
-}
-
-static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
-{
-	struct ntfs_i *ei = (struct ntfs_i *) foo;
-
-	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
-	    SLAB_CTOR_CONSTRUCTOR)
-		inode_init_once(&ei->vfs_inode);
-}
- 
-static int init_inodecache(void)
-{
-	ntfs_inode_cachep = kmem_cache_create("ntfs_inode_cache",
-					     sizeof(struct ntfs_i),
-					     0, SLAB_HWCACHE_ALIGN,
-					     init_once, NULL);
-	if (ntfs_inode_cachep == NULL)
-		return -ENOMEM;
-	return 0;
-}
-
-static void destroy_inodecache(void)
-{
-	if (kmem_cache_destroy(ntfs_inode_cachep))
-		printk(KERN_INFO "ntfs_inode_cache: not all structures were freed\n");
-}
-static struct super_operations ntfs_super_operations = {
-	alloc_inode:	__ntfs_alloc_inode,
-	destroy_inode:	ntfs_destroy_inode,
-	read_inode:	ntfs_read_inode,
-#ifdef CONFIG_NTFS_RW
-	write_inode:	ntfs_write_inode,
-#endif
-	put_super:	ntfs_put_super,
-	statfs:		ntfs_statfs,
-	remount_fs:	ntfs_remount_fs,
-	clear_inode:	_ntfs_clear_inode,
-};
-
-/**
- * is_boot_sector_ntfs - check an NTFS boot sector for validity
- * @b:		buffer containing bootsector to check
- * 
- * Check whether @b contains a valid NTFS boot sector.
- * Return 1 if @b is a valid NTFS bootsector or 0 if not.
- */
-static int is_boot_sector_ntfs(ntfs_u8 *b)
-{
-	ntfs_u32 i;
-
-	/* FIXME: We don't use checksumming yet as NT4(SP6a) doesn't either...
-	 * But we might as well have the code ready to do it. (AIA) */
-#if 0
-	/* Calculate the checksum. */
-	if (b < b + 0x50) {
-		ntfs_u32 *u;
-		ntfs_u32 *bi = (ntfs_u32 *)(b + 0x50);
-		
-		for (u = bi, i = 0; u < bi; ++u)
-			i += NTFS_GETU32(*u);
-	}
-#endif
-	/* Check magic is "NTFS    " */
-	if (b[3] != 0x4e) goto not_ntfs;
-	if (b[4] != 0x54) goto not_ntfs;
-	if (b[5] != 0x46) goto not_ntfs;
-	if (b[6] != 0x53) goto not_ntfs;
-	for (i = 7; i < 0xb; ++i)
-		if (b[i] != 0x20) goto not_ntfs;
-	/* Check bytes per sector value is between 512 and 4096. */
-	if (b[0xb] != 0) goto not_ntfs;
-	if (b[0xc] > 0x10) goto not_ntfs;
-	/* Check sectors per cluster value is valid. */
-	switch (b[0xd]) {
-	case 1: case 2: case 4: case 8: case 16:
-	case 32: case 64: case 128:
-		break;
-	default:
-		goto not_ntfs;
-	}
-	/* Check reserved sectors value and four other fields are zero. */
-	for (i = 0xe; i < 0x15; ++i) 
-		if (b[i] != 0) goto not_ntfs;
-	if (b[0x16] != 0) goto not_ntfs;
-	if (b[0x17] != 0) goto not_ntfs;
-	for (i = 0x20; i < 0x24; ++i)
-		if (b[i] != 0) goto not_ntfs;
-	/* Check clusters per file record segment value is valid. */
-	if (b[0x40] < 0xe1 || b[0x40] > 0xf7) {
-		switch (b[0x40]) {
-		case 1: case 2: case 4: case 8: case 16: case 32: case 64:
-			break;
-		default:
-			goto not_ntfs;
-		}
-	}
-	/* Check clusters per index block value is valid. */
-	if (b[0x44] < 0xe1 || b[0x44] > 0xf7) {
-		switch (b[0x44]) {
-		case 1: case 2: case 4: case 8: case 16: case 32: case 64:
-			break;
-		default:
-			goto not_ntfs;
-		}
-	}
-	return 1;
-not_ntfs:
-	return 0;
-}
-
-/* Called to mount a filesystem by read_super() in fs/super.c.
- * Return a super block, the main structure of a filesystem.
- *
- * NOTE : Don't store a pointer to an option, as the page containing the
- * options is freed after ntfs_read_super() returns.
- *
- * NOTE : A context switch can happen in kernel code only if the code blocks
- * (= calls schedule() in kernel/sched.c). */
-static int ntfs_fill_super(struct super_block *sb, void *options, int silent)
-{
-	ntfs_volume *vol;
-	struct buffer_head *bh;
-	int i, to_read, blocksize;
-
-	ntfs_debug(DEBUG_OTHER, "ntfs_read_super\n");
-	vol = NTFS_SB2VOL(sb);
-	init_ntfs_super_block(vol);
-	if (!parse_options(vol, (char*)options))
-		goto ntfs_read_super_vol;
-	blocksize = sb_min_blocksize(sb, 512);
-	if (!blocksize) {
-		ntfs_error("Unable to set blocksize.\n");
-		goto ntfs_read_super_vol;
-	}
-	/* Read the super block (boot block). */
-	if (!(bh = sb_bread(sb, 0))) {
-		ntfs_error("Reading super block failed\n");
-		goto ntfs_read_super_unl;
-	}
-	ntfs_debug(DEBUG_OTHER, "Done reading boot block\n");
-	/* Check for valid 'NTFS' boot sector. */
-	if (!is_boot_sector_ntfs(bh->b_data)) {
-		ntfs_debug(DEBUG_OTHER, "Not a NTFS volume\n");
-		bforget(bh);
-		goto ntfs_read_super_unl;
-	}
-	ntfs_debug(DEBUG_OTHER, "Going to init volume\n");
-	if (ntfs_init_volume(vol, bh->b_data) < 0) {
-		ntfs_debug(DEBUG_OTHER, "Init volume failed.\n");
-		bforget(bh);
-		goto ntfs_read_super_unl;
-	}
-	ntfs_debug(DEBUG_OTHER, "$Mft at cluster 0x%lx\n", vol->mft_lcn);
-	brelse(bh);
-	NTFS_SB(vol) = sb;
-	if (vol->cluster_size > PAGE_SIZE) {
-		ntfs_error("Partition cluster size is not supported yet (it "
-			   "is > max kernel blocksize).\n");
-		goto ntfs_read_super_unl;
-	}
-	ntfs_debug(DEBUG_OTHER, "Done to init volume\n");
-	/* Inform the kernel that a device block is a NTFS cluster. */
-	if (!sb_set_blocksize(sb, vol->cluster_size)) {
-		ntfs_error("Cluster size too small for device.\n");
-		goto ntfs_read_super_unl;
-	}
-	ntfs_debug(DEBUG_OTHER, "set_blocksize\n");
-	/* Allocate an MFT record (MFT record can be smaller than a cluster). */
-	i = vol->cluster_size;
-	if (i < vol->mft_record_size)
-		i = vol->mft_record_size;
-	if (!(vol->mft = ntfs_malloc(i)))
-		goto ntfs_read_super_unl;
-
-	/* Read at least the MFT record for $Mft. */
-	to_read = vol->mft_clusters_per_record;
-	if (to_read < 1)
-		to_read = 1;
-	for (i = 0; i < to_read; i++) {
-		if (!(bh = sb_bread(sb, vol->mft_lcn + i))) {
-			ntfs_error("Could not read $Mft record 0\n");
-			goto ntfs_read_super_mft;
-		}
-		ntfs_memcpy(vol->mft + ((__s64)i << vol->cluster_size_bits),
-						bh->b_data, vol->cluster_size);
-		brelse(bh);
-		ntfs_debug(DEBUG_OTHER, "Read cluster 0x%x\n",
-							 vol->mft_lcn + i);
-	}
-	/* Check and fixup this MFT record */
-	if (!ntfs_check_mft_record(vol, vol->mft)){
-		ntfs_error("Invalid $Mft record 0\n");
-		goto ntfs_read_super_mft;
-	}
-	/* Inform the kernel about which super operations are available. */
-	sb->s_op = &ntfs_super_operations;
-	sb->s_magic = NTFS_SUPER_MAGIC;
-	sb->s_maxbytes = MAX_LFS_FILESIZE;
-	ntfs_debug(DEBUG_OTHER, "Reading special files\n");
-	if (ntfs_load_special_files(vol)) {
-		ntfs_error("Error loading special files\n");
-		goto ntfs_read_super_mft;
-	}
-	ntfs_debug(DEBUG_OTHER, "Getting RootDir\n");
-	/* Get the root directory. */
-	if (!(sb->s_root = d_alloc_root(iget(sb, FILE_root)))) {
-		ntfs_error("Could not get root dir inode\n");
-		goto ntfs_read_super_mft;
-	}
-	return 0;
-ntfs_read_super_mft:
-	ntfs_free(vol->mft);
-ntfs_read_super_unl:
-ntfs_read_super_vol:
-	ntfs_debug(DEBUG_OTHER, "read_super: done\n");
-	return -EINVAL;
-}
-
-/* Define the filesystem */
-static struct super_block *ntfs_get_sb(struct file_system_type *fs_type,
-	int flags, char *dev_name, void *data)
-{
-	return get_sb_bdev(fs_type, flags, dev_name, data, ntfs_fill_super);
-}
-
-static struct file_system_type ntfs_fs_type = {
-	owner:		THIS_MODULE,
-	name:		"ntfs",
-	get_sb:		ntfs_get_sb,
-	kill_sb:	kill_block_super,
-	fs_flags:	FS_REQUIRES_DEV,
-};
-
-static int __init init_ntfs_fs(void)
-{
-	int err;
-	/* Comment this if you trust klogd. There are reasons not to trust it */
-#if defined(DEBUG) && !defined(MODULE)
-	console_verbose();
-#endif
-	printk(KERN_NOTICE "NTFS driver v" NTFS_VERSION " [Flags: R/"
-#ifdef CONFIG_NTFS_RW
-			"W"
-#else
-			"O"
-#endif
-#ifdef DEBUG
-			" DEBUG"
-#endif
-#ifdef MODULE
-			" MODULE"
-#endif
-			"]\n");
-	SYSCTL(1);
-	ntfs_debug(DEBUG_OTHER, "registering %s\n", ntfs_fs_type.name);
-	err = init_inodecache();
-	if (err)
-		goto out1;
-	err = register_filesystem(&ntfs_fs_type);
-	if (err)
-		goto out;
-	return 0;
-out:
-	destroy_inodecache();
-out1:
-	SYSCTL(0);
-	return err;
-}
-
-static void __exit exit_ntfs_fs(void)
-{
-	SYSCTL(0);
-	ntfs_debug(DEBUG_OTHER, "unregistering %s\n", ntfs_fs_type.name);
-	unregister_filesystem(&ntfs_fs_type);
-	destroy_inodecache();
-}
-
-EXPORT_NO_SYMBOLS;
-/*
- * Not strictly true. The driver was written originally by Martin von Lwis.
- * I am just maintaining and rewriting it.
- */
-MODULE_AUTHOR("Anton Altaparmakov <aia21@cus.cam.ac.uk>");
-MODULE_DESCRIPTION("Linux NTFS driver");
-MODULE_LICENSE("GPL");
-#ifdef DEBUG
-MODULE_PARM(ntdebug, "i");
-MODULE_PARM_DESC(ntdebug, "Debug level");
-#endif
-
-module_init(init_ntfs_fs)
-module_exit(exit_ntfs_fs)
-

fs/ntfs/inode.h

 /*
- * inode.h -  Header file for inode.c
+ * inode.h - Defines for inode structures NTFS Linux kernel driver. Part of
+ *	     the Linux-NTFS project.
  *
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (C) 1998 Martin von Lwis
- * Copyright (c) 2001 Anton Altparmakov (AIA)
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-ntfs_attribute *ntfs_find_attr(ntfs_inode *ino, int type, char *name);
-
-int ntfs_read_attr(ntfs_inode *ino, int type, char *name, __s64 offset,
-		ntfs_io *buf);
-
-int ntfs_write_attr(ntfs_inode *ino, int type, char *name, __s64 offset,
-		ntfs_io *buf);
+#ifndef _LINUX_NTFS_INODE_H
+#define _LINUX_NTFS_INODE_H
 
-int ntfs_init_inode(ntfs_inode *ino, ntfs_volume *vol, int inum);
+#include <linux/seq_file.h>
 
-void ntfs_clear_inode(ntfs_inode *ino);
+#include "volume.h"
 
-int ntfs_check_mft_record(ntfs_volume *vol, char *record);
+typedef struct _ntfs_inode ntfs_inode;
 
-int ntfs_alloc_inode(ntfs_inode *dir, ntfs_inode *result, const char *filename,
-		int namelen, ntfs_u32);
-
-int ntfs_alloc_file(ntfs_inode *dir, ntfs_inode *result, char *filename,
-		int namelen);
-
-int ntfs_update_inode(ntfs_inode *ino);
+/*
+ * The NTFS in-memory inode structure. It is just used as an extension to the
+ * fields already provided in the VFS inode.
+ */
+struct _ntfs_inode {
+	s64 initialized_size;	/* Copy from $DATA/$INDEX_ALLOCATION. */
+	s64 allocated_size;	/* Copy from $DATA/$INDEX_ALLOCATION. */
+	unsigned long state;	/* NTFS specific flags describing this inode.
+				   See fs/ntfs/ntfs.h:ntfs_inode_state_bits. */
+	u64 mft_no;		/* Mft record number (inode number). */
+	u16 seq_no;		/* Sequence number of the mft record. */
+	atomic_t count;		/* Inode reference count for book keeping. */
+	ntfs_volume *vol;	/* Pointer to the ntfs volume of this inode. */
+	run_list run_list;	/* If state has the NI_NonResident bit set,
+				   the run list of the unnamed data attribute
+				   (if a file) or of the index allocation
+				   attribute (directory). If run_list.rl is
+				   NULL, the run list has not been read in or
+				   has been unmapped. If NI_NonResident is
+				   clear, the unnamed data attribute is
+				   resident (file) or there is no $I30 index
+				   allocation attribute (directory). In that
+				   case run_list.rl is always NULL.*/
+	struct rw_semaphore mrec_lock;	/* Lock for serializing access to the
+				   mft record belonging to this inode. */
+	atomic_t mft_count;	/* Mapping reference count for book keeping. */
+	struct page *page;	/* The page containing the mft record of the
+				   inode. This should only be touched by the
+				   (un)map_mft_record*() functions. */
+	int page_ofs;		/* Offset into the page at which the mft record
+				   begins. This should only be touched by the
+				   (un)map_mft_record*() functions. */
+	/*
+	 * Attribute list support (only for use by the attribute lookup
+	 * functions). Setup during read_inode for all inodes with attribute
+	 * lists. Only valid if NI_AttrList is set in state, and attr_list_rl is
+	 * further only valid if NI_AttrListNonResident is set.
+	 */
+	u32 attr_list_size;	/* Length of attribute list value in bytes. */
+	u8 *attr_list;		/* Attribute list value itself. */
+	run_list attr_list_rl;	/* Run list for the attribute list value. */
+	union {
+		struct { /* It is a directory or $MFT. */
+			u32 index_block_size;	/* Size of an index block. */
+			u8 index_block_size_bits; /* Log2 of the above. */
+			u32 index_vcn_size;	/* Size of a vcn in this
+						   directory index. */
+			u8 index_vcn_size_bits;	/* Log2 of the above. */
+			s64 bmp_size;		/* Size of the $I30 bitmap. */
+			s64 bmp_initialized_size; /* Copy from $I30 bitmap. */
+			s64 bmp_allocated_size;	/* Copy from $I30 bitmap. */
+			run_list bmp_rl;	/* Run list for the $I30 bitmap
+						   if it is non-resident. */
+		} SN(idm);
+		struct { /* It is a compressed file. */
+			u32 compression_block_size;     /* Size of a compression
+						           block (cb). */
+			u8 compression_block_size_bits; /* Log2 of the size of
+							   a cb. */
+			u8 compression_block_clusters;  /* Number of clusters
+							   per compression
+							   block. */
+			s64 compressed_size;		/* Copy from $DATA. */
+		} SN(icf);
+	} SN(idc);
+	struct semaphore extent_lock;	/* Lock for accessing/modifying the
+					   below . */
+	s32 nr_extents;	/* For a base mft record, the number of attached extent
+			   inodes (0 if none), for extent records this is -1. */
+	union {		/* This union is only used if nr_extents != 0. */
+		ntfs_inode **extent_ntfs_inos;	/* For nr_extents > 0, array of
+						   the ntfs inodes of the extent
+						   mft records belonging to
+						   this base inode which have
+						   been loaded. */
+		ntfs_inode *base_ntfs_ino;	/* For nr_extents == -1, the
+						   vfs inode of the base mft
+						   record. */
+	} SN(ine);
+};
+
+#define _IDM(X)  SC(idc.idm,X)
+#define _ICF(X)  SC(idc.icf,X)
+#define _INE(X)  SC(ine,X)
+
+typedef struct {
+	ntfs_inode ntfs_inode;
+	struct inode vfs_inode;		/* The vfs inode structure. */
+} big_ntfs_inode;
+
+/**
+ * NTFS_I - return the ntfs inode given a vfs inode
+ * @inode:	VFS inode
+ *
+ * NTFS_I() returns the ntfs inode associated with the VFS @inode.
+ */
+static inline ntfs_inode *NTFS_I(struct inode *inode)
+{
+	return (ntfs_inode *)list_entry(inode, big_ntfs_inode, vfs_inode);
+}
 
-int ntfs_vcn_to_lcn(ntfs_inode *ino, int vcn);
+static inline struct inode *VFS_I(ntfs_inode *ni)
+{
+	return &((big_ntfs_inode*)ni)->vfs_inode;
+}
 
-int ntfs_readwrite_attr(ntfs_inode *ino, ntfs_attribute *attr, __s64 offset,
-		ntfs_io *dest);
+extern struct inode *ntfs_alloc_big_inode(struct super_block *sb);
+extern void ntfs_destroy_big_inode(struct inode *inode);
+extern void ntfs_clear_big_inode(struct inode *vi);
 
-int ntfs_allocate_attr_number(ntfs_inode *ino, int *result);
+extern ntfs_inode *ntfs_new_inode(struct super_block *sb);
+extern void ntfs_clear_inode(ntfs_inode *ni);
 
-int ntfs_decompress_run(unsigned char **data, int *length,
-		ntfs_cluster_t *cluster, int *ctype);
+extern void ntfs_read_inode(struct inode *vi);
+extern void ntfs_read_inode_mount(struct inode *vi);
 
-void ntfs_decompress(unsigned char *dest, unsigned char *src, ntfs_size_t l);
+extern void ntfs_dirty_inode(struct inode *vi);
 
-int splice_runlists(ntfs_runlist **rl1, int *r1len, const ntfs_runlist *rl2,
-		int r2len);
+extern int ntfs_show_options(struct seq_file *sf, struct vfsmount *mnt);
 
-/*
- * NOTE: Neither of the ntfs_*_bit functions are atomic! But we don't need
- * them atomic at present as we never operate on shared/cached bitmaps.
- */
-static __inline__ int ntfs_test_and_set_bit(unsigned char *byte, const int bit)
-{
-	unsigned char *ptr = byte + (bit >> 3);
-	int b = 1 << (bit & 7);
-	int oldbit = *ptr & b ? 1 : 0;
-	*ptr |= b;
-	return oldbit;
-}
+#endif /* _LINUX_NTFS_FS_INODE_H */
 

fs/ntfs/layout.h

+/*
+ * layout.h - All NTFS associated on-disk structures. Part of the Linux-NTFS
+ *	      project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_LAYOUT_H
+#define _LINUX_NTFS_LAYOUT_H
+
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/list.h>
+#include <asm/byteorder.h>
+
+#include "volume.h"
+
+/*
+ * Constant endianness conversion defines.
+ */
+#define const_le16_to_cpu(x)	__constant_le16_to_cpu(x)
+#define const_le32_to_cpu(x)	__constant_le32_to_cpu(x)
+#define const_le64_to_cpu(x)	__constant_le64_to_cpu(x)
+
+#define const_cpu_to_le16(x)	__constant_cpu_to_le16(x)
+#define const_cpu_to_le32(x)	__constant_cpu_to_le32(x)
+#define const_cpu_to_le64(x)	__constant_cpu_to_le64(x)
+
+/* The NTFS oem_id */
+#define magicNTFS	const_cpu_to_le64(0x202020205346544e) /* "NTFS    " */
+
+/*
+ * Location of bootsector on partition:
+ * 	The standard NTFS_BOOT_SECTOR is on sector 0 of the partition.
+ * 	On NT4 and above there is one backup copy of the boot sector to
+ * 	be found on the last sector of the partition (not normally accessible
+ * 	from within Windows as the bootsector contained number of sectors
+ *	value is one less than the actual value!).
+ * 	On versions of NT 3.51 and earlier, the backup copy was located at 
+ * 	number of sectors/2 (integer divide), i.e. in the middle of the volume.
+ */
+
+/*
+ * BIOS parameter block (bpb) structure.
+ */
+typedef struct {
+	u16 bytes_per_sector;		/* Size of a sector in bytes. */
+	u8  sectors_per_cluster;	/* Size of a cluster in sectors. */
+	u16 reserved_sectors;		/* zero */
+	u8  fats;			/* zero */
+	u16 root_entries;		/* zero */
+	u16 sectors;			/* zero */
+	u8  media_type;			/* 0xf8 = hard disk */
+	u16 sectors_per_fat;		/* zero */
+	u16 sectors_per_track;		/* irrelevant */
+	u16 heads;			/* irrelevant */
+	u32 hidden_sectors;		/* zero */
+	u32 large_sectors;		/* zero */
+} __attribute__ ((__packed__)) BIOS_PARAMETER_BLOCK;
+
+/*
+ * NTFS boot sector structure.
+ */
+typedef struct {
+	u8  jump[3];			/* Irrelevant (jump to boot up code).*/
+	u64 oem_id;			/* Magic "NTFS    ". */
+	BIOS_PARAMETER_BLOCK bpb;	/* See BIOS_PARAMETER_BLOCK. */
+	u8  unused[4];			/* zero */
+	s64 number_of_sectors;		/* Number of sectors in volume. Gives
+					   maximum volume size of 2^63 sectors.
+					   Assuming standard sector size of 512
+					   bytes, the maximum byte size is
+					   approx. 4.7x10^21 bytes. (-; */
+	s64 mft_lcn;			/* Cluster location of mft data. */
+	s64 mftmirr_lcn;		/* Cluster location of copy of mft. */
+	s8  clusters_per_mft_record;	/* Mft record size in clusters. */
+	u8  reserved0[3];		/* zero */
+	s8  clusters_per_index_record;	/* Index block size in clusters. */
+	u8  reserved1[3];		/* zero */
+	u64 volume_serial_number;	/* Irrelevant (serial number). */
+	u32 checksum;			/* Boot sector checksum. */
+	u8  bootstrap[426];		/* Irrelevant (boot up code). */
+	u16 end_of_sector_marker;	/* End of bootsector magic. Always is
+					   0xaa55 in little endian. */
+} __attribute__ ((__packed__)) NTFS_BOOT_SECTOR;
+
+/*
+ * Magic identifiers present at the beginning of all ntfs record containing
+ * records (like mft records for example).
+ */
+typedef enum {
+	magic_BAAD = const_cpu_to_le32(0x44414142), /* BAAD == corrupt record */
+	magic_CHKD = const_cpu_to_le32(0x424b4843), /* CHKD == chkdsk ??? */
+        magic_FILE = const_cpu_to_le32(0x454c4946), /* FILE == mft entry */
+	magic_HOLE = const_cpu_to_le32(0x454c4f48), /* HOLE == ? (NTFS 3.0+?) */
+        magic_INDX = const_cpu_to_le32(0x58444e49), /* INDX == index buffer */
+} NTFS_RECORD_TYPES;
+
+/*
+ * Generic magic comparison macros. Finally found a use for the ## preprocessor
+ * operator! (-8
+ */
+#define is_magic(x, m)		(   (u32)(x) == magic_##m )
+#define is_magicp(p, m) 	( *(u32*)(p) == magic_##m )
+
+/*
+ * Specialised magic comparison macros.
+ */
+#define is_baad_record(x)	( is_magic (x, BAAD) )
+#define is_baad_recordp(p)	( is_magicp(p, BAAD) )
+#define is_chkd_record(x)       ( is_magic (x, CHKD) )
+#define is_chkd_recordp(p)      ( is_magicp(p, CHKD) )
+#define is_file_record(x)	( is_magic (x, FILE) )
+#define is_file_recordp(p)	( is_magicp(p, FILE) )
+#define is_hole_record(x)       ( is_magic (x, HOLE) )
+#define is_hole_recordp(p)      ( is_magicp(p, HOLE) )
+#define is_indx_record(x)       ( is_magic (x, INDX) )
+#define is_indx_recordp(p)      ( is_magicp(p, INDX) )
+
+#define is_mft_record(x)	( is_file_record(x) )
+#define is_mft_recordp(p)	( is_file_recordp(p) )
+
+/*
+ * The Update Sequence Array (usa) is an array of the u16 values which belong
+ * to the end of each sector protected by the update sequence record in which
+ * this array is contained. Note that the first entry is the Update Sequence
+ * Number (usn), a cyclic counter of how many times the protected record has
+ * been written to disk. The values 0 and -1 (ie. 0xffff) are not used. All
+ * last u16's of each sector have to be equal to the usn (during reading) or
+ * are set to it (during writing). If they are not, an incomplete multi sector
+ * transfer has occured when the data was written.
+ * The maximum size for the update sequence array is fixed to:
+ * 	maximum size = usa_ofs + (usa_count * 2) = 510 bytes
+ * The 510 bytes comes from the fact that the last u16 in the array has to
+ * (obviously) finish before the last u16 of the first 512-byte sector.
+ * This formula can be used as a consistency check in that usa_ofs +
+ * (usa_count * 2) has to be less than or equal to 510.
+ */
+typedef struct {
+	NTFS_RECORD_TYPES magic;	/* A four-byte magic identifying the
+					   record type and/or status. */
+	u16 usa_ofs;		/* Offset to the Update Sequence Array (usa)
+				   from the start of the ntfs record. */
+	u16 usa_count;		/* Number of u16 sized entries in the usa
+				   including the Update Sequence Number (usn),
+				   thus the number of fixups is the usa_count
+				   minus 1. */
+} __attribute__ ((__packed__)) NTFS_RECORD;
+
+/*
+ * System files mft record numbers. All these files are always marked as used
+ * in the bitmap attribute of the mft; presumably in order to avoid accidental
+ * allocation for random other mft records. Also, the sequence number for each
+ * of the system files is always equal to their mft record number and it is
+ * never modified.
+ */
+typedef enum {
+	FILE_MFT       = 0,	/* Master file table (mft). Data attribute
+				   contains the entries and bitmap attribute
+				   records which ones are in use (bit==1). */
+	FILE_MFTMirr   = 1,	/* Mft mirror (copy of first four mft records)
+				   in data attribute. */
+	FILE_LogFile   = 2,	/* Journalling log in data attribute. */
+	FILE_Volume    = 3,	/* Volume name attribute and volume information
+				   attribute (flags and ntfs version). Windows
+				   refers to this file as volume DASD (Direct
+				   Access Storage Device). */
+	FILE_AttrDef   = 4,	/* Array of attribute definitions in data
+				   attribute. */
+	FILE_root      = 5,	/* Root directory. */
+	FILE_Bitmap    = 6,	/* Allocation bitmap of all clusters (lcns) in
+				   data attribute. */
+	FILE_Boot      = 7,	/* Boot sector (always at cluster 0) in data
+				   attribute. */
+	FILE_BadClus   = 8,	/* Contains all bad clusters in the non-resident
+				   data attribute. */
+	FILE_Secure    = 9,	/* Shared security descriptors in data attribute
+				   and two indexes into the descriptors.
+				   Appeared in Windows 2000. Before that, this
+				   file was named $Quota but was unused. */
+	FILE_UpCase    = 10,	/* Uppercase equivalents of all 65536 Unicode
+				   characters in data attribute. */
+	FILE_Extend    = 11,	/* Directory containing other system files (eg.
+				   $ObjId, $Quota, $Reparse and $UsnJrnl). This
+				   is new to NTFS3.0. */
+	FILE_reserved12 = 12,	/* Reserved for future use (records 12-15). */
+	FILE_reserved13 = 13,
+	FILE_reserved14 = 14,
+	FILE_reserved15 = 15,
+	FILE_first_user = 16,	/* First user file, used as test limit for
+				   whether to allow opening a file or not. */
+} NTFS_SYSTEM_FILES;
+
+/*
+ * These are the so far known MFT_RECORD_* flags (16-bit) which contain 
+ * information about the mft record in which they are present.
+ */
+typedef enum {
+	MFT_RECORD_IN_USE	= const_cpu_to_le16(0x0001),
+	MFT_RECORD_IS_DIRECTORY	= const_cpu_to_le16(0x0002),
+	MFT_REC_SPACE_FILLER	= 0xffff	/* Just to make flags 16-bit. */
+} __attribute__ ((__packed__)) MFT_RECORD_FLAGS;
+
+/*
+ * mft references (aka file references or file record segment references) are
+ * used whenever a structure needs to refer to a record in the mft.
+ * 
+ * A reference consists of a 48-bit index into the mft and a 16-bit sequence
+ * number used to detect stale references.
+ *
+ * For error reporting purposes we treat the 48-bit index as a signed quantity.
+ *
+ * The sequence number is a circular counter (skipping 0) describing how many
+ * times the referenced mft record has been (re)used. This has to match the
+ * sequence number of the mft record being referenced, otherwise the reference
+ * is considered stale and removed (FIXME: only ntfsck or the driver itself?).
+ *
+ * If the sequence number is zero it is assumed that no sequence number
+ * consistency checking should be performed.
+ *
+ * FIXME: Since inodes are 32-bit as of now, the driver needs to always check
+ * for high_part being 0 and if not either BUG(), cause a panic() or handle
+ * the situation in some other way. This shouldn't be a problem as a volume has
+ * to become HUGE in order to need more than 32-bits worth of mft records.
+ * Assuming the standard mft record size of 1kb only the records (never mind
+ * the non-resident attributes, etc.) would require 4Tb of space on their own
+ * for the first 32 bits worth of records. This is only if some strange person
+ * doesn't decide to foul play and make the mft sparse which would be a really
+ * horrible thing to do as it would trash our current driver implementation. )-:
+ * Do I hear screams "we want 64-bit inodes!" ?!? (-;
+ *
+ * FIXME: The mft zone is defined as the first 12% of the volume. This space is
+ * reserved so that the mft can grow contiguously and hence doesn't become 
+ * fragmented. Volume free space includes the empty part of the mft zone and
+ * when the volume's free 88% are used up, the mft zone is shrunk by a factor
+ * of 2, thus making more space available for more files/data. This process is
+ * repeated everytime there is no more free space except for the mft zone until
+ * there really is no more free space.
+ */
+
+/*
+ * Typedef the MFT_REF as a 64-bit value for easier handling.
+ * Also define two unpacking macros to get to the reference (MREF) and
+ * sequence number (MSEQNO) respectively.
+ * The _LE versions are to be applied on little endian MFT_REFs.
+ * Note: The _LE versions will return a CPU endian formatted value!
+ */
+typedef enum {
+	MFT_REF_MASK_CPU	= 0x0000ffffffffffffULL,
+	MFT_REF_MASK_LE		= const_cpu_to_le64(0x0000ffffffffffffULL),
+} MFT_REF_CONSTS;
+
+typedef u64 MFT_REF;
+
+#define MREF(x)		((u64)((x) & MFT_REF_MASK_CPU))
+#define MSEQNO(x)	((u16)(((x) >> 48) & 0xffff))
+#define MREF_LE(x)	((u64)(le64_to_cpu(x) & MFT_REF_MASK_CPU))
+#define MSEQNO_LE(x)	((u16)((le64_to_cpu(x) >> 48) & 0xffff))
+
+#define IS_ERR_MREF(x)	(((x) & 0x0000800000000000ULL) ? 1 : 0)
+#define ERR_MREF(x)	((u64)((s64)(x)))
+#define MREF_ERR(x)	((int)((s64)(x)))
+
+/*
+ * The mft record header present at the beginning of every record in the mft.
+ * This is followed by a sequence of variable length attribute records which
+ * is terminated by an attribute of type AT_END which is a truncated attribute
+ * in that it only consists of the attribute type code AT_END and none of the
+ * other members of the attribute structure are present.
+ */
+typedef struct {
+/*Ofs*/
+/*  0*/	NTFS_RECORD SN(mnr);	/* Usually the magic is "FILE". */
+/*  8*/	u64 lsn;		/* $LogFile sequence number for this record.
+				   Changed every time the record is modified. */
+/* 16*/	u16 sequence_number;	/* Number of times this mft record has been
+		   		   reused. (See description for MFT_REF
+				   above.) NOTE: The increment (skipping zero)
+				   is done when the file is deleted. NOTE: If
+				   this is zero it is left zero. */
+/* 18*/	u16 link_count; 	/* Number of hard links, i.e. the number of 
+				   directory entries referencing this record.
+				   NOTE: Only used in mft base records.
+				   NOTE: When deleting a directory entry we
+				   check the link_count and if it is 1 we
+				   delete the file. Otherwise we delete the
+				   FILE_NAME_ATTR being referenced by the
+				   directory entry from the mft record and
+				   decrement the link_count.
+				   FIXME: Careful with Win32 + DOS names! */
+/* 20*/	u16 attrs_offset;	/* Byte offset to the first attribute in this
+				   mft record from the start of the mft record.
+				   NOTE: Must be aligned to 8-byte boundary. */
+/* 22*/	MFT_RECORD_FLAGS flags;	/* Bit array of MFT_RECORD_FLAGS. When a file
+				   is deleted, the MFT_RECORD_IN_USE flag is
+				   set to zero. */
+/* 24*/	u32 bytes_in_use;	/* Number of bytes used in this mft record.
+				   NOTE: Must be aligned to 8-byte boundary. */
+/* 28*/	u32 bytes_allocated;	/* Number of bytes allocated for this mft
+				   record. This should be equal to the mft
+				   record size. */
+/* 32*/	MFT_REF base_mft_record; /* This is zero for base mft records.
+				   When it is not zero it is a mft reference
+				   pointing to the base mft record to which
+				   this record belongs (this is then used to
+				   locate the attribute list attribute present
+				   in the base record which describes this
+				   extension record and hence might need
+				   modification when the extension record
+				   itself is modified, also locating the
+				   attribute list also means finding the other
+				   potential extents, belonging to the non-base
+				   mft record). */
+/* 40*/	u16 next_attr_instance;	/* The instance number that will be
+				   assigned to the next attribute added to this
+				   mft record. NOTE: Incremented each time
+				   after it is used. NOTE: Every time the mft
+				   record is reused this number is set to zero.
+				   NOTE: The first instance number is always 0.
+				 */
+/* sizeof() = 42 bytes */
+/* NTFS 3.1+ (Windows XP and above) introduce the following additions. */
+/* 42*/ //u16 reserved;		/* Reserved/alignment. */
+/* 44*/ //u32 mft_record_number;/* Number of this mft record. */
+/* sizeof() = 48 bytes */
+/*
+ * When (re)using the mft record, we place the update sequence array at this
+ * offset, i.e. before we start with the attributes. This also makes sense,
+ * otherwise we could run into problems with the update sequence array
+ * containing in itself the last two bytes of a sector which would mean that
+ * multi sector transfer protection wouldn't work. As you can't protect data
+ * by overwriting it since you then can't get it back...
+ * When reading we obviously use the data from the ntfs record header.
+ */
+} __attribute__ ((__packed__)) MFT_RECORD;
+
+#define _MNR(X)  SC(mnr,X)
+
+/*
+ * System defined attributes (32-bit). Each attribute type has a corresponding
+ * attribute name (Unicode string of maximum 64 character length) as described
+ * by the attribute definitions present in the data attribute of the $AttrDef
+ * system file. On NTFS 3.0 volumes the names are just as the types are named
+ * in the below enum exchanging AT_ for the dollar sign ($). If that isn't a
+ * revealing choice of symbol... (-;
+ */
+typedef enum {
+	AT_UNUSED			= const_cpu_to_le32(         0),
+	AT_STANDARD_INFORMATION		= const_cpu_to_le32(      0x10),
+	AT_ATTRIBUTE_LIST		= const_cpu_to_le32(      0x20),
+	AT_FILE_NAME			= const_cpu_to_le32(      0x30),
+	AT_OBJECT_ID			= const_cpu_to_le32(      0x40),
+	AT_SECURITY_DESCRIPTOR		= const_cpu_to_le32(      0x50),
+	AT_VOLUME_NAME			= const_cpu_to_le32(      0x60),
+	AT_VOLUME_INFORMATION		= const_cpu_to_le32(      0x70),
+	AT_DATA				= const_cpu_to_le32(      0x80),
+	AT_INDEX_ROOT			= const_cpu_to_le32(      0x90),
+	AT_INDEX_ALLOCATION		= const_cpu_to_le32(      0xa0),
+	AT_BITMAP			= const_cpu_to_le32(      0xb0),
+	AT_REPARSE_POINT		= const_cpu_to_le32(      0xc0),
+	AT_EA_INFORMATION		= const_cpu_to_le32(      0xd0),
+	AT_EA				= const_cpu_to_le32(      0xe0),
+	AT_PROPERTY_SET			= const_cpu_to_le32(      0xf0),
+	AT_LOGGED_UTILITY_STREAM	= const_cpu_to_le32(     0x100),
+	AT_FIRST_USER_DEFINED_ATTRIBUTE	= const_cpu_to_le32(    0x1000),
+	AT_END				= const_cpu_to_le32(0xffffffff),
+} ATTR_TYPES;
+
+/*
+ * The collation rules for sorting views/indexes/etc (32-bit).
+ *
+ * COLLATION_UNICODE_STRING - Collate Unicode strings by comparing their binary
+ *	Unicode values, except that when a character can be uppercased, the
+ *	upper case value collates before the lower case one.
+ * COLLATION_FILE_NAME - Collate file names as Unicode strings. The collation
+ *	is done very much like COLLATION_UNICODE_STRING. In fact I have no idea
+ *	what the difference is. Perhaps the difference is that file names
+ *	would treat some special characters in an odd way (see
+ *	unistr.c::ntfs_collate_names() and unistr.c::legal_ansi_char_array[]
+ *	for what I mean but COLLATION_UNICODE_STRING would not give any special
+ *	treatment to any characters at all, but this is speculation.
+ * COLLATION_NTOFS_ULONG - Sorting is done according to ascending u32 key
+ * 	values. E.g. used for $SII index in FILE_Secure, which sorts by
+ * 	security_id (u32).
+ * COLLATION_NTOFS_SID - Sorting is done according to ascending SID values.
+ * 	E.g. used for $O index in FILE_Extend/$Quota.
+ * COLLATION_NTOFS_SECURITY_HASH - Sorting is done first by ascending hash
+ * 	values and second by ascending security_id values. E.g. used for $SDH
+ * 	index in FILE_Secure.
+ * COLLATION_NTOFS_ULONGS - Sorting is done according to a sequence of ascending
+ *	u32 key values. E.g. used for $O index in FILE_Extend/$ObjId, which
+ *	sorts by object_id (16-byte), by splitting up the object_id in four
+ *	u32 values and using them as individual keys. E.g. take the following
+ *	two security_ids, stored as follows on disk:
+ *		1st: a1 61 65 b7 65 7b d4 11 9e 3d 00 e0 81 10 42 59
+ *		2nd: 38 14 37 d2 d2 f3 d4 11 a5 21 c8 6b 79 b1 97 45
+ *	To compare them, they are split into four u32 values each, like so:
+ *		1st: 0xb76561a1 0x11d47b65 0xe0003d9e 0x59421081
+ *		2nd: 0xd2371438 0x11d4f3d2 0x6bc821a5 0x4597b179
+ *	Now, it is apparent why the 2nd object_id collates after the 1st: the
+ *	first u32 value of the 1st object_id is less than the first u32 of
+ *	the 2nd object_id. If the first u32 values of both object_ids were
+ *	equal then the second u32 values would be compared, etc.
+ */
+typedef enum {
+	COLLATION_BINARY	 = const_cpu_to_le32(0), /* Collate by binary
+					compare where the first byte is most
+					significant. */
+	COLLATION_FILE_NAME	 = const_cpu_to_le32(1), /* Collate file names
+					as Unicode strings. */
+	COLLATION_UNICODE_STRING = const_cpu_to_le32(2), /* Collate Unicode
+					strings by comparing their binary
+					Unicode values, except that when a
+					character can be uppercased, the upper
+					case value collates before the lower
+					case one. */
+	COLLATION_NTOFS_ULONG		= const_cpu_to_le32(16),
+	COLLATION_NTOFS_SID		= const_cpu_to_le32(17),
+	COLLATION_NTOFS_SECURITY_HASH	= const_cpu_to_le32(18),
+	COLLATION_NTOFS_ULONGS		= const_cpu_to_le32(19),
+} COLLATION_RULES;
+
+/*
+ * The flags (32-bit) describing attribute properties in the attribute
+ * definition structure. FIXME: This information is from Regis's information
+ * and, according to him, it is not certain and probably incomplete.
+ * The INDEXABLE flag is fairly certainly correct as only the file name
+ * attribute has this flag set and this is the only attribute indexed in NT4.
+ */
+typedef enum {
+	INDEXABLE	    = const_cpu_to_le32(0x02),	/* Attribute can be
+							   indexed. */
+	NEED_TO_REGENERATE  = const_cpu_to_le32(0x40),	/* Need to regenerate
+							   during regeneration
+							   phase. */
+	CAN_BE_NON_RESIDENT = const_cpu_to_le32(0x80),	/* Attribute can be
+							   non-resident. */
+} ATTR_DEF_FLAGS;
+
+/*
+ * The data attribute of FILE_AttrDef contains a sequence of attribute
+ * definitions for the NTFS volume. With this, it is supposed to be safe for an
+ * older NTFS driver to mount a volume containing a newer NTFS version without
+ * damaging it (that's the theory. In practice it's: not damaging it too much).
+ * Entries are sorted by attribute type. The flags describe whether the
+ * attribute can be resident/non-resident and possibly other things, but the
+ * actual bits are unknown.
+ */
+typedef struct {
+/*hex ofs*/
+/*  0*/	uchar_t name[0x40];		/* Unicode name of the attribute. Zero
+					   terminated. */
+/* 80*/	ATTR_TYPES type;		/* Type of the attribute. */
+/* 84*/	u32 display_rule;		/* Default display rule.
+					   FIXME: What does it mean? (AIA) */
+/* 88*/ COLLATION_RULES collation_rule;	/* Default collation rule. */
+/* 8c*/	ATTR_DEF_FLAGS flags;		/* Flags describing the attribute. */
+/* 90*/	u64 min_size;			/* Optional minimum attribute size. */
+/* 98*/	u64 max_size;			/* Maximum size of attribute. */
+/* sizeof() = 0xa0 or 160 bytes */
+} __attribute__ ((__packed__)) ATTR_DEF;
+
+/*
+ * Attribute flags (16-bit). 
+ */
+typedef enum {
+	ATTR_IS_COMPRESSED	= const_cpu_to_le16(0x0001),
+	ATTR_COMPRESSION_MASK	= const_cpu_to_le16(0x00ff),  /* Compression
+						method mask. Also, first
+						illegal value. */
+	ATTR_IS_ENCRYPTED	= const_cpu_to_le16(0x4000),
+	ATTR_IS_SPARSE		= const_cpu_to_le16(0x8000),
+} __attribute__ ((__packed__)) ATTR_FLAGS;
+
+/*
+ * Attribute compression.
+ *
+ * Only the data attribute is ever compressed in the current ntfs driver in
+ * Windows. Further, compression is only applied when the data attribute is
+ * non-resident. Finally, to use compression, the maximum allowed cluster size
+ * on a volume is 4kib.
+ *
+ * The compression method is based on independently compressing blocks of X
+ * clusters, where X is determined from the compression_unit value found in the
+ * non-resident attribute record header (more precisely: X = 2^compression_unit
+ * clusters). On Windows NT/2k, X always is 16 clusters (compression_unit = 4).
+ *
+ * There are three different cases of how a compression block of X clusters
+ * can be stored:
+ *
+ *   1) The data in the block is all zero (a sparse block):
+ *	  This is stored as a sparse block in the run list, i.e. the run list
+ *	  entry has length = X and lcn = -1. The mapping pairs array actually
+ *	  uses a delta_lcn value length of 0, i.e. delta_lcn is not present at
+ *	  all, which is then interpreted by the driver as lcn = -1.
+ *	  NOTE: Even uncompressed files can be sparse on NTFS 3.0 volumes, then
+ *	  the same principles apply as above, except that the length is not
+ *	  restricted to being any particular value.
+ *
+ *   2) The data in the block is not compressed:
+ *	  This happens when compression doesn't reduce the size of the block
+ *	  in clusters. I.e. if compression has a small effect so that the
+ *	  compressed data still occupies X clusters, then the uncompressed data
+ *	  is stored in the block.
+ *	  This case is recognised by the fact that the run list entry has
+ *	  length = X and lcn >= 0. The mapping pairs array stores this as
+ *	  normal with a run length of X and some specific delta_lcn, i.e.
+ *	  delta_lcn has to be present.
+ *
+ *   3) The data in the block is compressed:
+ *	  The common case. This case is recognised by the fact that the run
+ *	  list entry has length L < X and lcn >= 0. The mapping pairs array
+ *	  stores this as normal with a run length of X and some specific
+ *	  delta_lcn, i.e. delta_lcn has to be present. This run list entry is
+ *	  immediately followed by a sparse entry with length = X - L and
+ *	  lcn = -1. The latter entry is to make up the vcn counting to the
+ *	  full compression block size X.
+ *
+ * In fact, life is more complicated because adjacent entries of the same type
+ * can be coalesced. This means that one has to keep track of the number of
+ * clusters handled and work on a basis of X clusters at a time being one
+ * block. An example: if length L > X this means that this particular run list
+ * entry contains a block of length X and part of one or more blocks of length
+ * L - X. Another example: if length L < X, this does not necessarily mean that
+ * the block is compressed as it might be that the lcn changes inside the block
+ * and hence the following run list entry describes the continuation of the
+ * potentially compressed block. The block would be compressed if the
+ * following run list entry describes at least X - L sparse clusters, thus
+ * making up the compression block length as described in point 3 above. (Of
+ * course, there can be several run list entries with small lengths so that the
+ * sparse entry does not follow the first data containing entry with
+ * length < X.)
+ *
+ * NOTE: At the end of the compressed attribute value, there most likely is not
+ * just the right amount of data to make up a compression block, thus this data
+ * is not even attempted to be compressed. It is just stored as is, unless
+ * the number of clusters it occupies is reduced when compressed in which case
+ * it is stored as a compressed compression block, complete with sparse
+ * clusters at the end.
+ */
+
+/*
+ * Flags of resident attributes (8-bit).
+ */
+typedef enum {
+	RESIDENT_ATTR_IS_INDEXED = 0x01, /* Attribute is referenced in an index
+					    (has implications for deleting and
+					    modifying the attribute). */
+} __attribute__ ((__packed__)) RESIDENT_ATTR_FLAGS;
+
+/*
+ * Attribute record header. Always aligned to 8-byte boundary.
+ */
+typedef struct {
+/*Ofs*/
+/*  0*/	ATTR_TYPES type;	/* The (32-bit) type of the attribute. */
+/*  4*/	u32 length;		/* Byte size of the resident part of the
+				   attribute (aligned to 8-byte boundary).
+				   Used to get to the next attribute. */
+/*  8*/	u8 non_resident;	/* If 0, attribute is resident.
+				   If 1, attribute is non-resident. */
+/*  9*/	u8 name_length;		/* Unicode character size of name of attribute.
+				   0 if unnamed. */
+/* 10*/	u16 name_offset;	/* If name_length != 0, the byte offset to the
+				   beginning of the name from the attribute
+				   record. Note that the name is stored as a
+				   Unicode string. When creating, place offset
+				   just at the end of the record header. Then,
+				   follow with attribute value or mapping pairs
+				   array, resident and non-resident attributes
+				   respectively, aligning to an 8-byte
+				   boundary. */
+/* 12*/	ATTR_FLAGS flags;	/* Flags describing the attribute. */
+/* 14*/	u16 instance;		/* The instance of this attribute record. This
+				   number is unique within this mft record (see 
+				   MFT_RECORD/next_attribute_instance notes in
+				   in mft.h for more details). */
+/* 16*/	union {
+		/* Resident attributes. */
+		struct {
+/* 16 */		u32 value_length; /* Byte size of attribute value. */
+/* 20 */		u16 value_offset; /* Byte offset of the attribute
+					     value from the start of the
+					     attribute record. When creating,
+					     align to 8-byte boundary if we 
+					     have a name present as this might
+					     not have a length of a multiple
+					     of 8-bytes. */
+/* 22 */		RESIDENT_ATTR_FLAGS resident_flags; /* See above. */
+/* 23 */		s8 reservedR;	  /* Reserved/alignment to 8-byte
+					     boundary. */
+		} SN(ara) __attribute__ ((__packed__));
+		/* Non-resident attributes. */
+		struct {
+/* 16*/			VCN lowest_vcn;	/* Lowest valid virtual cluster number
+				for this portion of the attribute value or
+				0 if this is the only extent (usually the
+				case). - Only when an attribute list is used
+				does lowest_vcn != 0 ever occur. */
+/* 24*/			VCN highest_vcn; /* Highest valid vcn of this extent of
+				the attribute value. - Usually there is only one
+				portion, so this usually equals the attribute
+				value size in clusters minus 1. Can be -1 for
+				zero length files. Can be 0 for "single extent"
+				attributes. */
+/* 32*/			u16 mapping_pairs_offset; /* Byte offset from the
+				beginning of the structure to the mapping pairs
+				array which contains the mappings between the
+				vcns and the logical cluster numbers (lcns).
+				When creating, place this at the end of this
+				record header aligned to 8-byte boundary. */
+/* 34*/			u8 compression_unit; /* The compression unit expressed
+				as the log to the base 2 of the number of
+				clusters in a compression unit. 0 means not
+				compressed. (This effectively limits the
+				compression unit size to be a power of two
+				clusters.) WinNT4 only uses a value of 4. */
+/* 35*/			u8 reserved1[5];	/* Align to 8-byte boundary. */
+/* The sizes below are only used when lowest_vcn is zero, as otherwise it would
+   be difficult to keep them up-to-date.*/
+/* 40*/			s64 allocated_size;	/* Byte size of disk space
+				allocated to hold the attribute value. Always
+				is a multiple of the cluster size. When a file
+				is compressed, this field is a multiple of the
+				compression block size (2^compression_unit) and
+				it represents the logically allocated space
+				rather than the actual on disk usage. For this
+				use the compressed_size (see below). */
+/* 48*/			s64 data_size;	/* Byte size of the attribute
+				value. Can be larger than allocated_size if
+				attribute value is compressed or sparse. */
+/* 56*/			s64 initialized_size;	/* Byte size of initialized
+				portion of the attribute value. Usually equals
+				data_size. */
+/* sizeof(uncompressed attr) = 64*/
+/* 64*/			s64 compressed_size;	/* Byte size of the attribute
+				value after compression. Only present when
+				compressed. Always is a multiple of the
+				cluster size. Represents the actual amount of
+				disk space being used on the disk. */
+/* sizeof(compressed attr) = 72*/
+		} SN(anr) __attribute__ ((__packed__));
+	} SN(aua) __attribute__ ((__packed__));
+} __attribute__ ((__packed__)) ATTR_RECORD;
+
+#define _ARA(X)  SC(aua.ara,X)
+#define _ANR(X)  SC(aua.anr,X)
+
+typedef ATTR_RECORD ATTR_REC;
+
+/*
+ * File attribute flags (32-bit).
+ */
+typedef enum {
+	/*
+	 * These flags are only presnt in the STANDARD_INFORMATION attribute
+	 * (in the field file_attributes).
+	 */
+	FILE_ATTR_READONLY		= const_cpu_to_le32(0x00000001),
+	FILE_ATTR_HIDDEN		= const_cpu_to_le32(0x00000002),
+	FILE_ATTR_SYSTEM		= const_cpu_to_le32(0x00000004),
+	/* Old DOS volid. Unused in NT.	= cpu_to_le32(0x00000008), */
+
+	FILE_ATTR_DIRECTORY		= const_cpu_to_le32(0x00000010),
+	/* FILE_ATTR_DIRECTORY is not considered valid in NT. It is reserved
+	   for the DOS SUBDIRECTORY flag. */
+	FILE_ATTR_ARCHIVE		= const_cpu_to_le32(0x00000020),
+	FILE_ATTR_DEVICE		= const_cpu_to_le32(0x00000040),
+	FILE_ATTR_NORMAL		= const_cpu_to_le32(0x00000080),
+
+	FILE_ATTR_TEMPORARY		= const_cpu_to_le32(0x00000100),
+	FILE_ATTR_SPARSE_FILE		= const_cpu_to_le32(0x00000200),
+	FILE_ATTR_REPARSE_POINT		= const_cpu_to_le32(0x00000400),
+	FILE_ATTR_COMPRESSED		= const_cpu_to_le32(0x00000800),
+
+	FILE_ATTR_OFFLINE		= const_cpu_to_le32(0x00001000),
+	FILE_ATTR_NOT_CONTENT_INDEXED	= const_cpu_to_le32(0x00002000),
+	FILE_ATTR_ENCRYPTED		= const_cpu_to_le32(0x00004000),
+
+	FILE_ATTR_VALID_FLAGS		= const_cpu_to_le32(0x00007fb7),
+	/* FILE_ATTR_VALID_FLAGS masks out the old DOS VolId and the 
+	   FILE_ATTR_DEVICE and preserves everything else. This mask
+	   is used to obtain all flags that are valid for reading. */
+	FILE_ATTR_VALID_SET_FLAGS	= const_cpu_to_le32(0x000031a7),
+	/* FILE_ATTR_VALID_SET_FLAGS masks out the old DOS VolId, the
+	   F_A_DEVICE, F_A_DIRECTORY, F_A_SPARSE_FILE, F_A_REPARSE_POINT,
+	   F_A_COMPRESSED and F_A_ENCRYPTED and preserves the rest. This mask
+	   is used to to obtain all flags that are valid for setting. */
+
+	/*
+	 * These flags are only present in the FILE_NAME attribute (in the
+	 * field file_attributes).
+	 */
+	FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT	= const_cpu_to_le32(0x10000000),
+	/* This is a copy of the corresponding bit from the mft record, telling
+	   us whether this is a directory or not, i.e. whether it has an
+	   index root attribute or not. */
+	FILE_ATTR_DUP_VIEW_INDEX_PRESENT	= const_cpu_to_le32(0x20000000),
+	/* This is a copy of the corresponding bit from the mft record, telling
+	   us whether this file has a view index present (eg. object id index,
+	   quota index, one of the security indexes or the encrypting file
+	   system related indexes). */
+} FILE_ATTR_FLAGS;
+
+/*
+ * NOTE on times in NTFS: All times are in MS standard time format, i.e. they
+ * are the number of 100-nanosecond intervals since 1st January 1601, 00:00:00
+ * universal coordinated time (UTC). (In Linux time starts 1st January 1970,
+ * 00:00:00 UTC and is stored as the number of 1-second intervals since then.)
+ */
+
+/*
+ * Attribute: Standard information (0x10).
+ *
+ * NOTE: Always resident.
+ * NOTE: Present in all base file records on a volume.
+ * NOTE: There is conflicting information about the meaning of each of the time
+ * 	 fields but the meaning as defined below has been verified to be
+ * 	 correct by practical experimentation on Windows NT4 SP6a and is hence
+ * 	 assumed to be the one and only correct interpretation.
+ */
+typedef struct {
+/*Ofs*/
+/*  0*/	s64 creation_time;		/* Time file was created. Updated when
+					   a filename is changed(?). */
+/*  8*/	s64 last_data_change_time;	/* Time the data attribute was last
+					   modified. */
+/* 16*/	s64 last_mft_change_time;	/* Time this mft record was last
+					   modified. */
+/* 24*/	s64 last_access_time;		/* Approximate time when the file was
+					   last accessed (obviously this is not
+					   updated on read-only volumes). In
+					   Windows this is only updated when
+					   accessed if some time delta has
+					   passed since the last update. Also,
+					   last access times updates can be
+					   disabled altogether for speed. */
+/* 32*/	FILE_ATTR_FLAGS file_attributes; /* Flags describing the file. */
+/* 36*/	union {
+		/* NTFS 1.2 (and previous, presumably) */
+/* 36 */	u8 reserved12[12];	/* Reserved/alignment to 8-byte
+					   boundary. */
+/* sizeof() = 48 bytes */
+		/* NTFS 3.0 */
+		struct {
+/*
+ * If a volume has been upgraded from a previous NTFS version, then these
+ * fields are present only if the file has been accessed since the upgrade.
+ * Recognize the difference by comparing the length of the resident attribute
+ * value. If it is 48, then the following fields are missing. If it is 72 then
+ * the fields are present. Maybe just check like this:
+ * 	if (resident.ValueLength < sizeof(STANDARD_INFORMATION)) {
+ * 		Assume NTFS 1.2- format.
+ * 		If (volume version is 3.0+)
+ * 			Upgrade attribute to NTFS 3.0 format.
+ * 		else
+ * 			Use NTFS 1.2- format for access.
+ * 	} else
+ * 		Use NTFS 3.0 format for access.
+ * Only problem is that it might be legal to set the length of the value to
+ * arbitrarily large values thus spoiling this check. - But chkdsk probably
+ * views that as a corruption, assuming that it behaves like this for all
+ * attributes.
+ */
+		/* 36*/	u32 maximum_versions;	/* Maximum allowed versions for
+				file. Zero if version numbering is disabled. */
+		/* 40*/	u32 version_number;	/* This file's version (if any).
+				Set to zero if maximum_versions is zero. */
+		/* 44*/	u32 class_id;		/* Class id from bidirectional
+				class id index (?). */
+		/* 48*/	u32 owner_id;		/* Owner_id of the user owning
+				the file. Translate via $Q index in FILE_Extend
+				/$Quota to the quota control entry for the user
+				owning the file. Zero if quotas are disabled. */
+		/* 52*/	u32 security_id;	/* Security_id for the file.
+				Translate via $SII index and $SDS data stream
+				in FILE_Secure to the security descriptor. */
+		/* 56*/	u64 quota_charged;	/* Byte size of the charge to
+				the quota for all streams of the file. Note: Is
+				zero if quotas are disabled. */
+		/* 64*/	u64 usn;		/* Last update sequence number
+				of the file. This is a direct index into the
+				change (aka usn) journal file. It is zero if
+				the usn journal is disabled.
+				NOTE: To disable the journal need to delete
+				the journal file itself and to then walk the
+				whole mft and set all Usn entries in all mft
+				records to zero! (This can take a while!)
+				The journal is FILE_Extend/$UsnJrnl. Win2k
+				will recreate the journal and initiate
+				logging if necessary when mounting the
+				partition. This, in contrast to disabling the
+				journal is a very fast process, so the user
+				won't even notice it. */
+		} SN(svs);
+	} SN(sei);
+/* sizeof() = 72 bytes (NTFS 3.0) */
+} __attribute__ ((__packed__)) STANDARD_INFORMATION;
+
+#define _SVS(X)  SC(sei.svs,X)
+
+/*
+ * Attribute: Attribute list (0x20).
+ *
+ * - Can be either resident or non-resident.
+ * - Value consists of a sequence of variable length, 8-byte aligned,
+ * ATTR_LIST_ENTRY records.
+ * - The list is not terminated by anything at all! The only way to know when
+ * the end is reached is to keep track of the current offset and compare it to
+ * the attribute value size.
+ * - The attribute list attribute contains one entry for each attribute of
+ * the file in which the list is located, except for the list attribute
+ * itself. The list is sorted: first by attribute type, second by attribute
+ * name (if present), third by instance number. The extents of one
+ * non-resident attribute (if present) immediately follow after the initial
+ * extent. They are ordered by lowest_vcn and have their instace set to zero. 
+ * It is not allowed to have two attributes with all sorting keys equal.
+ * - Further restrictions: 
+ * 	- If not resident, the vcn to lcn mapping array has to fit inside the
+ * 	  base mft record.
+ * 	- The attribute list attribute value has a maximum size of 256kb. This
+ * 	  is imposed by the Windows cache manager.
+ * - Attribute lists are only used when the attributes of mft record do not
+ * fit inside the mft record despite all attributes (that can be made
+ * non-resident) having been made non-resident. This can happen e.g. when:
+ *  	- File has a large number of hard links (lots of file name
+ *  	  attributes present).
+ *  	- The mapping pairs array of some non-resident attribute becomes so
+ *	  large due to fragmentation that it overflows the mft record.
+ *  	- The security descriptor is very complex (not applicable to
+ *  	  NTFS 3.0 volumes).
+ *  	- There are many named streams.
+ */
+typedef struct {
+/*Ofs*/
+/*  0*/	ATTR_TYPES type;	/* Type of referenced attribute. */
+/*  4*/	u16 length;		/* Byte size of this entry (8-byte aligned). */
+/*  6*/	u8 name_length;		/* Size in Unicode chars of the name of the
+				   attribute or 0 if unnamed. */
+/*  7*/	u8 name_offset;		/* Byte offset to beginning of attribute name
+				   (always set this to where the name would
+				   start even if unnamed). */
+/*  8*/	VCN lowest_vcn;		/* Lowest virtual cluster number of this portion
+				   of the attribute value. This is usually 0. It
+				   is non-zero for the case where one attribute
+				   does not fit into one mft record and thus
+				   several mft records are allocated to hold
+				   this attribute. In the latter case, each mft
+				   record holds one extent of the attribute and
+				   there is one attribute list entry for each
+				   extent. NOTE: This is DEFINITELY a signed
+				   value! The windows driver uses cmp, followed
+				   by jg when comparing this, thus it treats it
+				   as signed. */
+/* 16*/	MFT_REF mft_reference;	/* The reference of the mft record holding
+				   the ATTR_RECORD for this portion of the
+				   attribute value. */
+/* 24*/	u16 instance;		/* If lowest_vcn = 0, the instance of the
+				   attribute being referenced; otherwise 0. */
+/* 26*/	uchar_t name[0];	/* Use when creating only. When reading use
+				   name_offset to determine the location of the
+				   name. */
+/* sizeof() = 26 + (attribute_name_length * 2) bytes */
+} __attribute__ ((__packed__)) ATTR_LIST_ENTRY;
+
+/*
+ * The maximum allowed length for a file name.
+ */
+#define MAXIMUM_FILE_NAME_LENGTH	255
+
+/*
+ * Possible namespaces for filenames in ntfs (8-bit).
+ */
+typedef enum {
+	FILE_NAME_POSIX			= 0x00,
+		/* This is the largest namespace. It is case sensitive and 
+		   allows all Unicode characters except for: '\0' and '/'.
+		   Beware that in WinNT/2k files which eg have the same name
+		   except for their case will not be distinguished by the
+		   standard utilities and thus a "del filename" will delete
+		   both "filename" and "fileName" without warning. */
+	FILE_NAME_WIN32			= 0x01,
+		/* The standard WinNT/2k NTFS long filenames. Case insensitive.
+		   All Unicode chars except: '\0', '"', '*', '/', ':', '<', 
+		   '>', '?', '\' and '|'. Further, names cannot end with a '.'
+		   or a space. */
+	FILE_NAME_DOS			= 0x02,
+		/* The standard DOS filenames (8.3 format). Uppercase only.
+		   All 8-bit characters greater space, except: '"', '*', '+',
+		   ',', '/', ':', ';', '<', '=', '>', '?' and '\'. */
+	FILE_NAME_WIN32_AND_DOS		= 0x03, 
+		/* 3 means that both the Win32 and the DOS filenames are
+		   identical and hence have been saved in this single filename
+		   record. */
+} __attribute__ ((__packed__)) FILE_NAME_TYPE_FLAGS;
+
+/*
+ * Attribute: Filename (0x30).
+ *
+ * NOTE: Always resident.
+ * NOTE: All fields, except the parent_directory, are only updated when the
+ *	 filename is changed. Until then, they just become out of sync with
+ *	 reality and the more up to date values are present in the standard
+ *	 information attribute.
+ * NOTE: There is conflicting information about the meaning of each of the time
+ * 	 fields but the meaning as defined below has been verified to be
+ * 	 correct by practical experimentation on Windows NT4 SP6a and is hence
+ * 	 assumed to be the one and only correct interpretation.
+ */
+typedef struct {
+/*hex ofs*/
+/*  0*/	MFT_REF parent_directory;	/* Directory this filename is
+					   referenced from. */
+/*  8*/	s64 creation_time;		/* Time file was created. */
+/* 10*/	s64 last_data_change_time;	/* Time the data attribute was last
+					   modified. */
+/* 18*/	s64 last_mft_change_time;	/* Time this mft record was last
+					   modified. */
+/* 20*/	s64 last_access_time;		/* Last time this mft record was
+					   accessed. */
+/* 28*/	s64 allocated_size;		/* Byte size of allocated space for the
+					   data attribute. NOTE: Is a multiple
+					   of the cluster size. */
+/* 30*/	s64 data_size;			/* Byte size of actual data in data
+					   attribute. NOTE: Only present when
+					   lowest_vcn is 0. */
+/* 38*/	FILE_ATTR_FLAGS file_attributes;	/* Flags describing the file. */
+/* 3c*/	union {
+	/* 3c*/	struct {
+		/* 3c*/	u16 packed_ea_size;	/* Size of the buffer needed to
+						   pack the extended attributes
+						   (EAs), if such are present.*/
+		/* 3e*/	u16 reserved;		/* Reserved for alignment. */
+		} SN(fea) __attribute__ ((__packed__));
+	/* 3c*/	u32 reparse_point_tag;		/* Type of reparse point,
+						   present only in reparse
+						   points and only if there are
+						   no EAs. */
+	} SN(fer) __attribute__ ((__packed__));
+/* 40*/	u8 file_name_length;			/* Length of file name in
+						   (Unicode) characters. */
+/* 41*/	FILE_NAME_TYPE_FLAGS file_name_type;	/* Namespace of the file name.*/
+/* 42*/	uchar_t file_name[0];			/* File name in Unicode. */
+} __attribute__ ((__packed__)) FILE_NAME_ATTR;
+
+#define _FEA(X)  SC(fer.fea,X)
+#define _FER(X)  SC(fer,X)
+
+/*
+ * GUID structures store globally unique identifiers (GUID). A GUID is a 
+ * 128-bit value consisting of one group of eight hexadecimal digits, followed
+ * by three groups of four hexadecimal digits each, followed by one group of
+ * twelve hexadecimal digits. GUIDs are Microsoft's implementation of the
+ * distributed computing environment (DCE) universally unique identifier (UUID).
+ * Example of a GUID:
+ * 	1F010768-5A73-BC91-0010A52216A7
+ */
+typedef struct {
+	u32 data1;	/* The first eight hexadecimal digits of the GUID. */
+	u16 data2;	/* The first group of four hexadecimal digits. */
+	u16 data3;	/* The second group of four hexadecimal digits. */
+	u8 data4[8];	/* The first two bytes are the third group of four
+			   hexadecimal digits. The remaining six bytes are the
+			   final 12 hexadecimal digits. */
+} __attribute__ ((__packed__)) GUID;
+
+/*
+ * FILE_Extend/$ObjId contains an index named $O. This index contains all
+ * object_ids present on the volume as the index keys and the corresponding
+ * mft_record numbers as the index entry data parts. The data part (defined
+ * below) also contains three other object_ids:
+ *	birth_volume_id - object_id of FILE_Volume on which the file was first
+ *			  created. Optional (i.e. can be zero).
+ *	birth_object_id - object_id of file when it was first created. Usually
+ *			  equals the object_id. Optional (i.e. can be zero).
+ *	domain_id	- Reserved (always zero).
+ */
+typedef struct {
+	MFT_REF mft_reference;	/* Mft record containing the object_id in
+				   the index entry key. */
+	union {
+		struct {
+			GUID birth_volume_id;
+			GUID birth_object_id;
+			GUID domain_id;
+		} SN(obv) __attribute__ ((__packed__));
+		u8 extended_info[48];
+	} SN(oei) __attribute__ ((__packed__));
+} __attribute__ ((__packed__)) OBJ_ID_INDEX_DATA;
+
+/*
+ * Attribute: Object id (NTFS 3.0+) (0x40).
+ *
+ * NOTE: Always resident.
+ */
+typedef struct {
+	GUID object_id;				/* Unique id assigned to the
+						   file.*/
+	/* The following fields are optional. The attribute value size is 16
+	   bytes, i.e. sizeof(GUID), if these are not present at all. Note,
+	   the entries can be present but one or more (or all) can be zero
+	   meaning that that particular value(s) is(are) not defined. */
+	union {
+		struct {
+			GUID birth_volume_id;	/* Unique id of volume on which
+						   the file was first created.*/
+			GUID birth_object_id;	/* Unique id of file when it was
+						   first created. */
+			GUID domain_id;		/* Reserved, zero. */
+		} SN(obv) __attribute__ ((__packed__));
+		u8 extended_info[48];
+	} SN(oei) __attribute__ ((__packed__));
+} __attribute__ ((__packed__)) OBJECT_ID_ATTR;
+
+#define _OBV(X)  SC(oei.obv,X)
+
+/*
+ * The pre-defined IDENTIFIER_AUTHORITIES used as SID_IDENTIFIER_AUTHORITY in
+ * the SID structure (see below).
+ */
+//typedef enum {					/* SID string prefix. */
+//	SECURITY_NULL_SID_AUTHORITY	= {0, 0, 0, 0, 0, 0},	/* S-1-0 */
+//	SECURITY_WORLD_SID_AUTHORITY	= {0, 0, 0, 0, 0, 1},	/* S-1-1 */
+//	SECURITY_LOCAL_SID_AUTHORITY 	= {0, 0, 0, 0, 0, 2},	/* S-1-2 */
+//	SECURITY_CREATOR_SID_AUTHORITY	= {0, 0, 0, 0, 0, 3},	/* S-1-3 */
+//	SECURITY_NON_UNIQUE_AUTHORITY	= {0, 0, 0, 0, 0, 4},	/* S-1-4 */
+//	SECURITY_NT_SID_AUTHORITY	= {0, 0, 0, 0, 0, 5},	/* S-1-5 */
+//} IDENTIFIER_AUTHORITIES;
+
+/*
+ * These relative identifiers (RIDs) are used with the above identifier
+ * authorities to make up universal well-known SIDs.
+ * 	
+ * Note: The relative identifier (RID) refers to the portion of a SID, which
+ * identifies a user or group in relation to the authority that issued the SID.
+ * For example, the universal well-known SID Creator Owner ID (S-1-3-0) is
+ * made up of the identifier authority SECURITY_CREATOR_SID_AUTHORITY (3) and
+ * the relative identifier SECURITY_CREATOR_OWNER_RID (0).
+ */
+typedef enum {					/* Identifier authority. */
+	SECURITY_NULL_RID		  = 0,	/* S-1-0 */
+	SECURITY_WORLD_RID		  = 0,	/* S-1-1 */
+	SECURITY_LOCAL_RID		  = 0,	/* S-1-2 */
+	
+	SECURITY_CREATOR_OWNER_RID	  = 0,	/* S-1-3 */
+	SECURITY_CREATOR_GROUP_RID	  = 1,	/* S-1-3 */
+
+	SECURITY_CREATOR_OWNER_SERVER_RID = 2,	/* S-1-3 */
+	SECURITY_CREATOR_GROUP_SERVER_RID = 3,	/* S-1-3 */
+
+	SECURITY_DIALUP_RID		  = 1,
+	SECURITY_NETWORK_RID		  = 2,
+	SECURITY_BATCH_RID		  = 3,
+	SECURITY_INTERACTIVE_RID	  = 4,
+	SECURITY_SERVICE_RID		  = 6,
+	SECURITY_ANONYMOUS_LOGON_RID	  = 7,
+	SECURITY_PROXY_RID		  = 8,
+	SECURITY_ENTERPRISE_CONTROLLERS_RID=9,
+	SECURITY_SERVER_LOGON_RID	  = 9,
+	SECURITY_PRINCIPAL_SELF_RID	  = 0xa,
+	SECURITY_AUTHENTICATED_USER_RID	  = 0xb,
+	SECURITY_RESTRICTED_CODE_RID	  = 0xc,
+	SECURITY_TERMINAL_SERVER_RID	  = 0xd,
+	
+	SECURITY_LOGON_IDS_RID		  = 5,
+	SECURITY_LOGON_IDS_RID_COUNT	  = 3,
+	
+	SECURITY_LOCAL_SYSTEM_RID	  = 0x12,
+
+	SECURITY_NT_NON_UNIQUE		  = 0x15,
+
+	SECURITY_BUILTIN_DOMAIN_RID	  = 0x20,
+
+	/*
+	 * Well-known domain relative sub-authority values (RIDs).
+	 */
+	
+	/* Users. */
+	DOMAIN_USER_RID_ADMIN		  = 0x1f4,
+	DOMAIN_USER_RID_GUEST		  = 0x1f5,
+	DOMAIN_USER_RID_KRBTGT		  = 0x1f6,
+	
+	/* Groups. */
+	DOMAIN_GROUP_RID_ADMINS		  = 0x200,
+	DOMAIN_GROUP_RID_USERS		  = 0x201,
+	DOMAIN_GROUP_RID_GUESTS		  = 0x202,
+	DOMAIN_GROUP_RID_COMPUTERS	  = 0x203,
+	DOMAIN_GROUP_RID_CONTROLLERS	  = 0x204,
+	DOMAIN_GROUP_RID_CERT_ADMINS	  = 0x205,
+	DOMAIN_GROUP_RID_SCHEMA_ADMINS	  = 0x206,
+	DOMAIN_GROUP_RID_ENTERPRISE_ADMINS= 0x207,
+	DOMAIN_GROUP_RID_POLICY_ADMINS	  = 0x208,
+
+	/* Aliases. */
+	DOMAIN_ALIAS_RID_ADMINS		  = 0x220,
+	DOMAIN_ALIAS_RID_USERS		  = 0x221,
+	DOMAIN_ALIAS_RID_GUESTS		  = 0x222,
+	DOMAIN_ALIAS_RID_POWER_USERS	  = 0x223,
+	
+	DOMAIN_ALIAS_RID_ACCOUNT_OPS	  = 0x224,
+	DOMAIN_ALIAS_RID_SYSTEM_OPS	  = 0x225,
+	DOMAIN_ALIAS_RID_PRINT_OPS	  = 0x226,
+	DOMAIN_ALIAS_RID_BACKUP_OPS	  = 0x227,
+	
+	DOMAIN_ALIAS_RID_REPLICATOR	  = 0x228,
+	DOMAIN_ALIAS_RID_RAS_SERVERS	  = 0x229,
+	DOMAIN_ALIAS_RID_PREW2KCOMPACCESS = 0x22a,
+} RELATIVE_IDENTIFIERS;
+
+/*
+ * The universal well-known SIDs:
+ *
+ * 	NULL_SID			S-1-0-0
+ * 	WORLD_SID			S-1-1-0
+ * 	LOCAL_SID			S-1-2-0
+ * 	CREATOR_OWNER_SID		S-1-3-0
+ * 	CREATOR_GROUP_SID		S-1-3-1
+ * 	CREATOR_OWNER_SERVER_SID	S-1-3-2
+ * 	CREATOR_GROUP_SERVER_SID	S-1-3-3
+ *
+ * 	(Non-unique IDs)		S-1-4
+ *
+ * NT well-known SIDs:
+ * 
+ * 	NT_AUTHORITY_SID	S-1-5
+ * 	DIALUP_SID		S-1-5-1
+ *
+ * 	NETWORD_SID		S-1-5-2
+ * 	BATCH_SID		S-1-5-3
+ * 	INTERACTIVE_SID		S-1-5-4
+ * 	SERVICE_SID		S-1-5-6
+ * 	ANONYMOUS_LOGON_SID	S-1-5-7		(aka null logon session)
+ * 	PROXY_SID		S-1-5-8
+ * 	SERVER_LOGON_SID	S-1-5-9		(aka domain controller account)
+ * 	SELF_SID		S-1-5-10	(self RID)
+ * 	AUTHENTICATED_USER_SID	S-1-5-11
+ * 	RESTRICTED_CODE_SID	S-1-5-12	(running restricted code)
+ * 	TERMINAL_SERVER_SID	S-1-5-13	(running on terminal server)
+ *
+ * 	(Logon IDs)		S-1-5-5-X-Y
+ *
+ * 	(NT non-unique IDs)	S-1-5-0x15-...
+ *
+ * 	(Built-in domain)	S-1-5-0x20
+ */
+
+/*
+ * The SID_IDENTIFIER_AUTHORITY is a 48-bit value used in the SID structure.
+ */
+typedef union {
+	struct {
+		u32 low_part;         /* Low 32-bits. */
+		u16 high_part;        /* High 16-bits. */
+	} SN(sia) __attribute__ ((__packed__));
+	u8 value[6];			/* Value as individual bytes. */
+} __attribute__ ((__packed__)) SID_IDENTIFIER_AUTHORITY;
+
+#define _SIA(X)  SC(sia,X)
+
+/*
+ * The SID structure is a variable-length structure used to uniquely identify
+ * users or groups. SID stands for security identifier.
+ * 
+ * The standard textual representation of the SID is of the form:
+ * 	S-R-I-S-S...
+ * Where:
+ *    - The first "S" is the literal character 'S' identifying the following
+ * 	digits as a SID.
+ *    - R is the revision level of the SID expressed as a sequence of digits
+ *	either in decimal or hexadecimal (if the later, prefixed by "0x").
+ *    - I is the 48-bit identifier_authority, expressed as digits as R above.
+ *    - S... is one or more sub_authority values, expressed as digits as above.
+ *    
+ * Example SID; the domain-relative SID of the local Administrators group on
+ * Windows NT/2k:
+ * 	S-1-5-32-544
+ * This translates to a SID with:
+ * 	revision = 1,
+ * 	sub_authority_count = 2,
+ * 	identifier_authority = {0,0,0,0,0,5},	// SECURITY_NT_AUTHORITY
+ * 	sub_authority[0] = 32,			// SECURITY_BUILTIN_DOMAIN_RID
+ * 	sub_authority[1] = 544			// DOMAIN_ALIAS_RID_ADMINS
+ */
+typedef struct {
+	u8 revision;
+	u8 sub_authority_count;
+	SID_IDENTIFIER_AUTHORITY identifier_authority;
+	u32 sub_authority[1];		/* At least one sub_authority. */
+} __attribute__ ((__packed__)) SID;
+
+/*
+ * Current constants for SIDs.
+ */
+typedef enum {
+	SID_REVISION			=  1,	/* Current revision level. */
+	SID_MAX_SUB_AUTHORITIES		= 15,	/* Maximum number of those. */
+	SID_RECOMMENDED_SUB_AUTHORITIES	=  1,	/* Will change to around 6 in
+						   a future revision. */
+} SID_CONSTANTS;
+
+/*
+ * The predefined ACE types (8-bit, see below).
+ */
+typedef enum {
+	ACCESS_MIN_MS_ACE_TYPE		= 0,
+	ACCESS_ALLOWED_ACE_TYPE		= 0,
+	ACCESS_DENIED_ACE_TYPE		= 1,
+	SYSTEM_AUDIT_ACE_TYPE		= 2,
+	SYSTEM_ALARM_ACE_TYPE		= 3, /* Not implemented as of Win2k. */
+	ACCESS_MAX_MS_V2_ACE_TYPE	= 3,
+
+	ACCESS_ALLOWED_COMPOUND_ACE_TYPE= 4,
+	ACCESS_MAX_MS_V3_ACE_TYPE	= 4,
+	
+	/* The following are Win2k only. */
+	ACCESS_MIN_MS_OBJECT_ACE_TYPE	= 5,
+	ACCESS_ALLOWED_OBJECT_ACE_TYPE	= 5,
+	ACCESS_DENIED_OBJECT_ACE_TYPE	= 6,
+	SYSTEM_AUDIT_OBJECT_ACE_TYPE	= 7,
+	SYSTEM_ALARM_OBJECT_ACE_TYPE	= 8,
+	ACCESS_MAX_MS_OBJECT_ACE_TYPE	= 8,
+
+	ACCESS_MAX_MS_V4_ACE_TYPE	= 8,
+
+	/* This one is for WinNT&2k. */
+	ACCESS_MAX_MS_ACE_TYPE		= 8,
+} __attribute__ ((__packed__)) ACE_TYPES;
+
+/*
+ * The ACE flags (8-bit) for audit and inheritance (see below).
+ *
+ * SUCCESSFUL_ACCESS_ACE_FLAG is only used with system audit and alarm ACE
+ * types to indicate that a message is generated (in Windows!) for successful
+ * accesses.
+ *
+ * FAILED_ACCESS_ACE_FLAG is only used with system audit and alarm ACE types
+ * to indicate that a message is generated (in Windows!) for failed accesses.
+ */
+typedef enum {
+	/* The inheritance flags. */
+	OBJECT_INHERIT_ACE		= 0x01,
+	CONTAINER_INHERIT_ACE		= 0x02,
+	NO_PROPAGATE_INHERIT_ACE	= 0x04,
+	INHERIT_ONLY_ACE		= 0x08,
+	INHERITED_ACE			= 0x10,	/* Win2k only. */
+	VALID_INHERIT_FLAGS		= 0x1f,
+
+	/* The audit flags. */
+	SUCCESSFUL_ACCESS_ACE_FLAG	= 0x40,
+	FAILED_ACCESS_ACE_FLAG		= 0x80,
+} __attribute__ ((__packed__)) ACE_FLAGS;
+
+/*
+ * An ACE is an access-control entry in an access-control list (ACL).
+ * An ACE defines access to an object for a specific user or group or defines
+ * the types of access that generate system-administration messages or alarms
+ * for a specific user or group. The user or group is identified by a security
+ * identifier (SID).
+ *
+ * Each ACE starts with an ACE_HEADER structure (aligned on 4-byte boundary),
+ * which specifies the type and size of the ACE. The format of the subsequent
+ * data depends on the ACE type.
+ */
+typedef struct {
+	ACE_TYPES type;		/* Type of the ACE. */
+	ACE_FLAGS flags;	/* Flags describing the ACE. */
+	u16 size;		/* Size in bytes of the ACE. */
+} __attribute__ ((__packed__)) ACE_HEADER;
+
+/*
+ * The access mask (32-bit). Defines the access rights.
+ */
+typedef enum {
+	/*
+	 * The specific rights (bits 0 to 15). Depend on the type of the
+	 * object being secured by the ACE.
+	 */
+
+	/* Specific rights for files and directories are as follows: */
+	
+	/* Right to read data from the file. (FILE) */
+	FILE_READ_DATA			= const_cpu_to_le32(0x00000001),
+	/* Right to list contents of a directory. (DIRECTORY) */
+	FILE_LIST_DIRECTORY		= const_cpu_to_le32(0x00000001),
+	
+	/* Right to write data to the file. (FILE) */
+	FILE_WRITE_DATA			= const_cpu_to_le32(0x00000002),
+	/* Right to create a file in the directory. (DIRECTORY) */
+	FILE_ADD_FILE			= const_cpu_to_le32(0x00000002),
+	
+	/* Right to append data to the file. (FILE) */
+	FILE_APPEND_DATA		= const_cpu_to_le32(0x00000004),
+	/* Right to create a subdirectory. (DIRECTORY) */
+	FILE_ADD_SUBDIRECTORY		= const_cpu_to_le32(0x00000004),
+	
+	/* Right to read extended attributes. (FILE/DIRECTORY) */
+	FILE_READ_EA			= const_cpu_to_le32(0x00000008),
+	
+	/* Right to write extended attributes. (FILE/DIRECTORY) */
+	FILE_WRITE_EA			= const_cpu_to_le32(0x00000010),
+	
+	/* Right to execute a file. (FILE) */
+	FILE_EXECUTE			= const_cpu_to_le32(0x00000020),
+	/* Right to traverse the directory. (DIRECTORY) */
+	FILE_TRAVERSE			= const_cpu_to_le32(0x00000020),
+	
+	/*
+	 * Right to delete a directory and all the files it contains (its
+	 * children), even if the files are read-only. (DIRECTORY)
+	 */
+	FILE_DELETE_CHILD		= const_cpu_to_le32(0x00000040),
+
+	/* Right to read file attributes. (FILE/DIRECTORY) */
+	FILE_READ_ATTRIBUTES		= const_cpu_to_le32(0x00000080),
+	
+	/* Right to change file attributes. (FILE/DIRECTORY) */
+	FILE_WRITE_ATTRIBUTES		= const_cpu_to_le32(0x00000100),
+	
+	/*
+	 * The standard rights (bits 16 to 23). Are independent of the type of
+	 * object being secured.
+	 */
+
+	/* Right to delete the object. */
+	DELETE				= const_cpu_to_le32(0x00010000),
+
+	/*
+	 * Right to read the information in the object's security descriptor,
+	 * not including the information in the SACL. I.e. right to read the
+	 * security descriptor and owner.
+	 */
+	READ_CONTROL			= const_cpu_to_le32(0x00020000),
+
+	/* Right to modify the DACL in the object's security descriptor. */
+	WRITE_DAC			= const_cpu_to_le32(0x00040000),
+
+	/* Right to change the owner in the object's security descriptor. */
+	WRITE_OWNER			= const_cpu_to_le32(0x00080000),
+
+	/*
+	 * Right to use the object for synchronization. Enables a process to
+	 * wait until the object is in the signalled state. Some object types
+	 * do not support this access right.
+	 */
+	SYNCHRONIZE			= const_cpu_to_le32(0x00100000),
+
+	/*
+	 * The following STANDARD_RIGHTS_* are combinations of the above for
+	 * convenience and are defined by the Win32 API.
+	 */
+	
+	/* These are currently defined to READ_CONTROL. */
+	STANDARD_RIGHTS_READ		= const_cpu_to_le32(0x00020000),
+	STANDARD_RIGHTS_WRITE		= const_cpu_to_le32(0x00020000),
+	STANDARD_RIGHTS_EXECUTE		= const_cpu_to_le32(0x00020000),
+	
+	/* Combines DELETE, READ_CONTROL, WRITE_DAC, and WRITE_OWNER access. */
+	STANDARD_RIGHTS_REQUIRED	= const_cpu_to_le32(0x000f0000),
+	
+	/*
+	 * Combines DELETE, READ_CONTROL, WRITE_DAC, WRITE_OWNER, and
+	 * SYNCHRONIZE access.
+	 */
+	STANDARD_RIGHTS_ALL		= const_cpu_to_le32(0x001f0000),
+
+	/*
+	 * The access system ACL and maximum allowed access types (bits 24 to
+	 * 25, bits 26 to 27 are reserved).
+	 */
+	ACCESS_SYSTEM_SECURITY		= const_cpu_to_le32(0x01000000),
+	MAXIMUM_ALLOWED			= const_cpu_to_le32(0x02000000),
+
+	/*
+	 * The generic rights (bits 28 to 31). These map onto the standard and
+	 * specific rights.
+	 */
+
+	/* Read, write, and execute access. */
+	GENERIC_ALL			= const_cpu_to_le32(0x10000000),
+
+	/* Execute access. */
+	GENERIC_EXECUTE			= const_cpu_to_le32(0x20000000),
+
+	/*
+	 * Write access. For files, this maps onto:
+	 *	FILE_APPEND_DATA | FILE_WRITE_ATTRIBUTES | FILE_WRITE_DATA |
+	 *	FILE_WRITE_EA | STANDARD_RIGHTS_WRITE | SYNCHRONIZE
+	 * For directories, the mapping has the same numberical value. See
+	 * above for the descriptions of the rights granted.
+	 */
+	GENERIC_WRITE			= const_cpu_to_le32(0x40000000),
+
+	/*
+	 * Read access. For files, this maps onto:
+	 *	FILE_READ_ATTRIBUTES | FILE_READ_DATA | FILE_READ_EA |
+	 *	STANDARD_RIGHTS_READ | SYNCHRONIZE
+	 * For directories, the mapping has the same numberical value. See
+	 * above for the descriptions of the rights granted.
+	 */
+	GENERIC_READ			= const_cpu_to_le32(0x80000000),
+} ACCESS_MASK;
+
+/*
+ * The generic mapping array. Used to denote the mapping of each generic
+ * access right to a specific access mask.
+ * 
+ * FIXME: What exactly is this and what is it for? (AIA)
+ */
+typedef struct {
+	ACCESS_MASK generic_read;
+	ACCESS_MASK generic_write;
+	ACCESS_MASK generic_execute;
+	ACCESS_MASK generic_all;
+} __attribute__ ((__packed__)) GENERIC_MAPPING;
+
+/*
+ * The predefined ACE type structures are as defined below.
+ */
+
+/*
+ * ACCESS_ALLOWED_ACE, ACCESS_DENIED_ACE, SYSTEM_AUDIT_ACE, SYSTEM_ALARM_ACE
+ */
+typedef struct {
+	ACE_HEADER SN(aah);		/* The ACE header. */
+	ACCESS_MASK mask;	/* Access mask associated with the ACE. */
+	SID sid;		/* The SID associated with the ACE. */
+} __attribute__ ((__packed__)) ACCESS_ALLOWED_ACE, ACCESS_DENIED_ACE,
+			       SYSTEM_AUDIT_ACE, SYSTEM_ALARM_ACE;
+#define _AAH(X)  SC(aah,X)
+
+/*
+ * The object ACE flags (32-bit).
+ */
+typedef enum {
+	ACE_OBJECT_TYPE_PRESENT			= const_cpu_to_le32(1),
+	ACE_INHERITED_OBJECT_TYPE_PRESENT	= const_cpu_to_le32(2),
+} OBJECT_ACE_FLAGS;
+
+typedef struct {
+	ACE_HEADER SN(aah);	/* The ACE_HEADER. */
+	ACCESS_MASK mask;	/* Access mask associated with the ACE. */
+	OBJECT_ACE_FLAGS flags;	/* Flags describing the object ACE. */
+	GUID object_type;
+	GUID inherited_object_type;
+	SID sid;		/* The SID associated with the ACE. */
+} __attribute__ ((__packed__)) ACCESS_ALLOWED_OBJECT_ACE,
+			       ACCESS_DENIED_OBJECT_ACE,
+			       SYSTEM_AUDIT_OBJECT_ACE,
+			       SYSTEM_ALARM_OBJECT_ACE;
+
+/*
+ * An ACL is an access-control list (ACL).
+ * An ACL starts with an ACL header structure, which specifies the size of
+ * the ACL and the number of ACEs it contains. The ACL header is followed by
+ * zero or more access control entries (ACEs). The ACL as well as each ACE
+ * are aligned on 4-byte boundaries.
+ */
+typedef struct {
+	u8 revision;	/* Revision of this ACL. */
+	u8 alignment1;
+	u16 size;	/* Allocated space in bytes for ACL. Includes this
+			   header, the ACEs and the remaining free space. */
+	u16 ace_count;	/* Number of ACEs in the ACL. */
+	u16 alignment2;
+/* sizeof() = 8 bytes */
+} __attribute__ ((__packed__)) ACL;
+
+/*
+ * Current constants for ACLs.
+ */
+typedef enum {
+	/* Current revision. */
+	ACL_REVISION		= 2,
+	ACL_REVISION_DS		= 4,
+
+	/* History of revisions. */
+	ACL_REVISION1		= 1,
+	MIN_ACL_REVISION	= 2,
+	ACL_REVISION2		= 2,
+	ACL_REVISION3		= 3,
+	ACL_REVISION4		= 4,
+	MAX_ACL_REVISION	= 4,
+} ACL_CONSTANTS;
+
+/*
+ * The security descriptor control flags (16-bit).
+ *
+ * SE_OWNER_DEFAULTED - This boolean flag, when set, indicates that the
+ *          SID pointed to by the Owner field was provided by a
+ *          defaulting mechanism rather than explicitly provided by the
+ *          original provider of the security descriptor.  This may
+ *          affect the treatment of the SID with respect to inheritence
+ *          of an owner.
+ *
+ * SE_GROUP_DEFAULTED - This boolean flag, when set, indicates that the
+ *          SID in the Group field was provided by a defaulting mechanism
+ *          rather than explicitly provided by the original provider of
+ *          the security descriptor.  This may affect the treatment of
+ *          the SID with respect to inheritence of a primary group.
+ *
+ * SE_DACL_PRESENT - This boolean flag, when set, indicates that the
+ *          security descriptor contains a discretionary ACL.  If this
+ *          flag is set and the Dacl field of the SECURITY_DESCRIPTOR is
+ *          null, then a null ACL is explicitly being specified.
+ *
+ * SE_DACL_DEFAULTED - This boolean flag, when set, indicates that the
+ *          ACL pointed to by the Dacl field was provided by a defaulting
+ *          mechanism rather than explicitly provided by the original
+ *          provider of the security descriptor.  This may affect the
+ *          treatment of the ACL with respect to inheritence of an ACL.
+ *          This flag is ignored if the DaclPresent flag is not set.
+ *
+ * SE_SACL_PRESENT - This boolean flag, when set,  indicates that the
+ *          security descriptor contains a system ACL pointed to by the
+ *          Sacl field.  If this flag is set and the Sacl field of the
+ *          SECURITY_DESCRIPTOR is null, then an empty (but present)
+ *          ACL is being specified.
+ *
+ * SE_SACL_DEFAULTED - This boolean flag, when set, indicates that the
+ *          ACL pointed to by the Sacl field was provided by a defaulting
+ *          mechanism rather than explicitly provided by the original
+ *          provider of the security descriptor.  This may affect the
+ *          treatment of the ACL with respect to inheritence of an ACL.
+ *          This flag is ignored if the SaclPresent flag is not set.
+ *
+ * SE_SELF_RELATIVE - This boolean flag, when set, indicates that the
+ *          security descriptor is in self-relative form.  In this form,
+ *          all fields of the security descriptor are contiguous in memory
+ *          and all pointer fields are expressed as offsets from the
+ *          beginning of the security descriptor.
+ */
+typedef enum {
+	SE_OWNER_DEFAULTED		= const_cpu_to_le16(0x0001),
+	SE_GROUP_DEFAULTED		= const_cpu_to_le16(0x0002),
+	SE_DACL_PRESENT			= const_cpu_to_le16(0x0004),
+	SE_DACL_DEFAULTED		= const_cpu_to_le16(0x0008),
+	SE_SACL_PRESENT			= const_cpu_to_le16(0x0010),
+	SE_SACL_DEFAULTED		= const_cpu_to_le16(0x0020),
+	SE_DACL_AUTO_INHERIT_REQ	= const_cpu_to_le16(0x0100),
+	SE_SACL_AUTO_INHERIT_REQ	= const_cpu_to_le16(0x0200),
+	SE_DACL_AUTO_INHERITED		= const_cpu_to_le16(0x0400),
+	SE_SACL_AUTO_INHERITED		= const_cpu_to_le16(0x0800),
+	SE_DACL_PROTECTED		= const_cpu_to_le16(0x1000),
+	SE_SACL_PROTECTED		= const_cpu_to_le16(0x2000),
+	SE_RM_CONTROL_VALID		= const_cpu_to_le16(0x4000),
+	SE_SELF_RELATIVE		= const_cpu_to_le16(0x8000),
+} __attribute__ ((__packed__)) SECURITY_DESCRIPTOR_CONTROL;
+
+/*
+ * Self-relative security descriptor. Contains the owner and group SIDs as well
+ * as the sacl and dacl ACLs inside the security descriptor itself.
+ */
+typedef struct {
+	u8 revision;	/* Revision level of the security descriptor. */
+	u8 alignment;
+	SECURITY_DESCRIPTOR_CONTROL control; /* Flags qualifying the type of
+			   the descriptor as well as the following fields. */
+	u32 owner;	/* Byte offset to a SID representing an object's
+			   owner. If this is NULL, no owner SID is present in
+			   the descriptor. */
+	u32 group;	/* Byte offset to a SID representing an object's
+			   primary group. If this is NULL, no primary group
+			   SID is present in the descriptor. */
+	u32 sacl;	/* Byte offset to a system ACL. Only valid, if
+			   SE_SACL_PRESENT is set in the control field. If
+			   SE_SACL_PRESENT is set but sacl is NULL, a NULL ACL
+			   is specified. */
+	u32 dacl;	/* Byte offset to a discretionary ACL. Only valid, if 
+			   SE_DACL_PRESENT is set in the control field. If
+			   SE_DACL_PRESENT is set but dacl is NULL, a NULL ACL
+			   (unconditionally granting access) is specified. */
+/* sizeof() = 0x14 bytes */
+} __attribute__ ((__packed__)) SECURITY_DESCRIPTOR_RELATIVE;
+
+/*
+ * Absolute security descriptor. Does not contain the owner and group SIDs, nor
+ * the sacl and dacl ACLs inside the security descriptor. Instead, it contains
+ * pointers to these structures in memory. Obviously, absolute security
+ * descriptors are only useful for in memory representations of security
+ * descriptors. On disk, a self-relative security descriptor is used.
+ */
+typedef struct {
+	u8 revision;	/* Revision level of the security descriptor. */
+	u8 alignment;
+	SECURITY_DESCRIPTOR_CONTROL control;	/* Flags qualifying the type of 
+			   the descriptor as well as the following fields. */
+	SID *owner;	/* Points to a SID representing an object's owner. If
+			   this is NULL, no owner SID is present in the
+			   descriptor. */
+	SID *group;	/* Points to a SID representing an object's primary
+			   group. If this is NULL, no primary group SID is
+			   present in the descriptor. */
+	ACL *sacl;	/* Points to a system ACL. Only valid, if
+			   SE_SACL_PRESENT is set in the control field. If
+			   SE_SACL_PRESENT is set but sacl is NULL, a NULL ACL
+			   is specified. */
+	ACL *dacl;	/* Points to a discretionary ACL. Only valid, if 
+			   SE_DACL_PRESENT is set in the control field. If
+			   SE_DACL_PRESENT is set but dacl is NULL, a NULL ACL
+			   (unconditionally granting access) is specified. */
+} __attribute__ ((__packed__)) SECURITY_DESCRIPTOR;
+
+/*
+ * Current constants for security descriptors.
+ */
+typedef enum {
+	/* Current revision. */
+	SECURITY_DESCRIPTOR_REVISION	= 1,
+	SECURITY_DESCRIPTOR_REVISION1	= 1,
+
+	/* The sizes of both the absolute and relative security descriptors is
+	   the same as pointers, at least on ia32 architecture are 32-bit. */
+	SECURITY_DESCRIPTOR_MIN_LENGTH	= sizeof(SECURITY_DESCRIPTOR),
+} SECURITY_DESCRIPTOR_CONSTANTS;
+
+/*
+ * Attribute: Security descriptor (0x50). A standard self-relative security
+ * descriptor.
+ *
+ * NOTE: Can be resident or non-resident.
+ * NOTE: Not used in NTFS 3.0+, as security descriptors are stored centrally
+ * in FILE_Secure and the correct descriptor is found using the security_id
+ * from the standard information attribute.
+ */
+typedef SECURITY_DESCRIPTOR_RELATIVE SECURITY_DESCRIPTOR_ATTR;
+
+/*
+ * On NTFS 3.0+, all security descriptors are stored in FILE_Secure. Only one
+ * referenced instance of each unique security descriptor is stored.
+ * 
+ * FILE_Secure contains no unnamed data attribute, i.e. it has zero length. It
+ * does, however, contain two indexes ($SDH and $SII) as well as a named data
+ * stream ($SDS).
+ * 
+ * Every unique security descriptor is assigned a unique security identifier
+ * (security_id, not to be confused with a SID). The security_id is unique for
+ * the NTFS volume and is used as an index into the $SII index, which maps
+ * security_ids to the security descriptor's storage location within the $SDS
+ * data attribute. The $SII index is sorted by ascending security_id.
+ *
+ * A simple hash is computed from each security descriptor. This hash is used
+ * as an index into the $SDH index, which maps security descriptor hashes to
+ * the security descriptor's storage location within the $SDS data attribute.
+ * The $SDH index is sorted by security descriptor hash and is stored in a B+
+ * tree. When searching $SDH (with the intent of determining whether or not a
+ * new security descriptor is already present in the $SDS data stream), if a
+ * matching hash is found, but the security descriptors do not match, the
+ * search in the $SDH index is continued, searching for a next matching hash.
+ * 
+ * When a precise match is found, the security_id coresponding to the security
+ * descriptor in the $SDS attribute is read from the found $SDH index entry and
+ * is stored in the $STANDARD_INFORMATION attribute of the file/directory to
+ * which the security descriptor is being applied. The $STANDARD_INFORMATION
+ * attribute is present in all base mft records (i.e. in all files and 
+ * directories).
+ *
+ * If a match is not found, the security descriptor is assigned a new unique
+ * security_id and is added to the $SDS data attribute. Then, entries
+ * referencing the this security descriptor in the $SDS data attribute are
+ * added to the $SDH and $SII indexes.
+ *
+ * Note: Entries are never deleted from FILE_Secure, even if nothing
+ * references an entry any more.
+ */
+ 
+/*
+ * This header precedes each security descriptor in the $SDS data stream.
+ * This is also the index entry data part of both the $SII and $SDH indexes.
+ */
+typedef struct {
+	u32 hash;	   /* Hash of the security descriptor. */
+	u32 security_id;   /* The security_id assigned to the descriptor. */
+	u64 offset;	   /* Byte offset of this entry in the $SDS stream. */
+	u32 length;	   /* Size in bytes of this entry in $SDS stream. */
+} __attribute__ ((__packed__)) SECURITY_DESCRIPTOR_HEADER;
+
+/*
+ * The $SDS data stream contains the security descriptors, aligned on 16-byte
+ * boundaries, sorted by security_id in a B+ tree. Security descriptors cannot
+ * cross 256kib boundaries (this restriction is imposed by the Windows cache
+ * manager). Each security descriptor is contained in a SDS_ENTRY structure.
+ * Also, each security descriptor is stored twice in the $SDS stream with a
+ * fixed offset of 0x40000 bytes (256kib, the Windows cache manager's max size)
+ * between them; i.e. if a SDS_ENTRY specifies an offset of 0x51d0, then the
+ * the first copy of the security descriptor will be at offset 0x51d0 in the
+ * $SDS data stream and the second copy will be at offset 0x451d0.
+ */
+typedef struct {
+	SECURITY_DESCRIPTOR_HEADER SN(sdh);	  /* The security descriptor header. */
+	SECURITY_DESCRIPTOR_RELATIVE sid; /* The self-relative security
+					     descriptor. */
+} __attribute__ ((__packed__)) SDS_ENTRY;
+
+#define _SDH(X)  SC(sdh,X)
+
+/*
+ * The index entry key used in the $SII index. The collation type is
+ * COLLATION_NTOFS_ULONG. 
+ */
+typedef struct {
+	u32 security_id; /* The security_id assigned to the descriptor. */
+} __attribute__ ((__packed__)) SII_INDEX_KEY;
+
+/*
+ * The index entry key used in the $SDH index. The keys are sorted first by
+ * hash and then by security_id. The collation rule is
+ * COLLATION_NTOFS_SECURITY_HASH.
+ */
+typedef struct {
+	u32 hash;	   /* Hash of the security descriptor. */
+	u32 security_id;   /* The security_id assigned to the descriptor. */
+} __attribute__ ((__packed__)) SDH_INDEX_KEY;
+
+/*
+ * Attribute: Volume name (0x60).
+ * 
+ * NOTE: Always resident.
+ * NOTE: Present only in FILE_Volume.
+ */
+typedef struct {
+	uchar_t name[0];		/* The name of the volume in Unicode. */
+} __attribute__ ((__packed__)) VOLUME_NAME;
+
+/*
+ * Possible flags for the volume (16-bit).
+ */
+typedef enum {
+	VOLUME_IS_DIRTY			= const_cpu_to_le16(0x0001),
+	VOLUME_RESIZE_LOG_FILE		= const_cpu_to_le16(0x0002),
+	VOLUME_UPGRADE_ON_MOUNT 	= const_cpu_to_le16(0x0004),
+	VOLUME_MOUNTED_ON_NT4		= const_cpu_to_le16(0x0008),
+	VOLUME_DELETE_USN_UNDERWAY	= const_cpu_to_le16(0x0010),
+	VOLUME_REPAIR_OBJECT_ID		= const_cpu_to_le16(0x0020),
+	VOLUME_MODIFIED_BY_CHKDSK	= const_cpu_to_le16(0x8000),
+	VOLUME_FLAGS_MASK		= const_cpu_to_le16(0x803f),
+} __attribute__ ((__packed__)) VOLUME_FLAGS;
+
+/*
+ * Attribute: Volume information (0x70).
+ *
+ * NOTE: Always resident.
+ * NOTE: Present only in FILE_Volume.
+ * NOTE: Windows 2000 uses NTFS 3.0 while Windows NT4 service pack 6a uses
+ * 	 NTFS 1.2. I haven't personally seen other values yet.
+ */
+typedef struct {
+	u64 reserved;		/* Not used (yet?). */
+	u8 major_ver;		/* Major version of the ntfs format. */
+	u8 minor_ver;		/* Minor version of the ntfs format. */
+	VOLUME_FLAGS flags;	/* Bit array of VOLUME_* flags. */
+} __attribute__ ((__packed__)) VOLUME_INFORMATION;
+
+/*
+ * Attribute: Data attribute (0x80).
+ *
+ * NOTE: Can be resident or non-resident.
+ *
+ * Data contents of a file (i.e. the unnamed stream) or of a named stream.
+ */
+typedef struct {
+	u8 data[0];		/* The file's data contents. */
+} __attribute__ ((__packed__)) DATA_ATTR;
+
+/*
+ * Index header flags (8-bit).
+ */
+typedef enum {
+	/* When index header is in an index root attribute: */
+	SMALL_INDEX	= 0, /* The index is small enough to fit inside the
+				index root attribute and there is no index
+				allocation attribute present. */
+	LARGE_INDEX	= 1, /* The index is too large to fit in the index
+				root attribute and/or an index allocation
+				attribute is present. */
+	/*
+	 * When index header is in an index block, i.e. is part of index
+	 * allocation attribute:
+	 */
+	LEAF_NODE	= 0, /* This is a leaf node, i.e. there are no more
+			        nodes branching off it. */
+	INDEX_NODE	= 1, /* This node indexes other nodes, i.e. is not a
+				leaf node. */
+	NODE_MASK	= 1, /* Mask for accessing the *_NODE bits. */
+} __attribute__ ((__packed__)) INDEX_HEADER_FLAGS;
+
+/*
+ * This is the header for indexes, describing the INDEX_ENTRY records, which
+ * follow the INDEX_HEADER. Together the index header and the index entries
+ * make up a complete index.
+ *
+ * IMPORTANT NOTE: The offset, length and size structure members are counted
+ * relative to the start of the index header structure and not relative to the
+ * start of the index root or index allocation structures themselves.
+ */
+typedef struct {
+	u32 entries_offset;		/* Byte offset to first INDEX_ENTRY
+					   aligned to 8-byte boundary. */
+	u32 index_length;		/* Data size of the index in bytes,
+					   i.e. bytes used from allocated
+					   size, aligned to 8-byte boundary. */
+	u32 allocated_size;		/* Byte size of this index (block),
+					   multiple of 8 bytes. */
+	/* NOTE: For the index root attribute, the above two numbers are always
+	   equal, as the attribute is resident and it is resized as needed. In
+	   the case of the index allocation attribute the attribute is not
+	   resident and hence the allocated_size is a fixed value and must
+	   equal the index_block_size specified by the INDEX_ROOT attribute
+	   corresponding to the INDEX_ALLOCATION attribute this INDEX_BLOCK
+	   belongs to. */
+	INDEX_HEADER_FLAGS flags;	/* Bit field of INDEX_HEADER_FLAGS. */
+	u8 reserved[3];			/* Reserved/align to 8-byte boundary. */
+} __attribute__ ((__packed__)) INDEX_HEADER;
+
+/*
+ * Attribute: Index root (0x90).
+ *
+ * NOTE: Always resident.
+ *
+ * This is followed by a sequence of index entries (INDEX_ENTRY structures)
+ * as described by the index header.
+ *
+ * When a directory is small enough to fit inside the index root then this
+ * is the only attribute describing the directory. When the directory is too
+ * large to fit in the index root, on the other hand, two aditional attributes
+ * are present: an index allocation attribute, containing sub-nodes of the B+
+ * directory tree (see below), and a bitmap attribute, describing which virtual
+ * cluster numbers (vcns) in the index allocation attribute are in use by an
+ * index block.
+ *
+ * NOTE: The root directory (FILE_root) contains an entry for itself. Other
+ * dircetories do not contain entries for themselves, though.
+ */
+typedef struct {
+	ATTR_TYPES type;		/* Type of the indexed attribute. Is
+					   $FILE_NAME for directories, zero
+					   for view indexes. No other values
+					   allowed. */
+	COLLATION_RULES collation_rule;	/* Collation rule used to sort the
+					   index entries. If type is $FILE_NAME,
+					   this must be COLLATION_FILE_NAME. */
+	u32 index_block_size;		/* Size of each index block in bytes (in
+					   the index allocation attribute). */
+	u8 clusters_per_index_block;	/* Cluster size of each index block (in
+					   the index allocation attribute), when
+					   an index block is >= than a cluster,
+					   otherwise this will be the log of
+					   the size (like how the encoding of 
+					   the mft record size and the index
+					   record size found in the boot sector
+					   work). Has to be a power of 2. */
+	u8 reserved[3];			/* Reserved/align to 8-byte boundary. */
+	INDEX_HEADER index;		/* Index header describing the
+					   following index entries. */
+} __attribute__ ((__packed__)) INDEX_ROOT;
+
+/*
+ * Attribute: Index allocation (0xa0).
+ *
+ * NOTE: Always non-resident (doesn't make sense to be resident anyway!).
+ * 
+ * This is an array of index blocks. Each index block starts with an
+ * INDEX_BLOCK structure containing an index header, followed by a sequence of
+ * index entries (INDEX_ENTRY structures), as described by the INDEX_HEADER.
+ */
+typedef struct {
+/*  0*/	NTFS_RECORD SN(inr);	/* Magic is "INDX". */
+/*  8*/	s64 lsn;		/* $LogFile sequence number of the last
+				   modification of this index block. */
+/* 16*/	VCN index_block_vcn;	/* Virtual cluster number of the index block.
+				   If the cluster_size on the volume is <= the
+				   index_block_size of the directory,
+				   index_block_vcn counts in units of clusters,
+				   and in units of sectors otherwise. */
+/* 24*/	INDEX_HEADER index;	/* Describes the following index entries. */
+/* sizeof()= 40 (0x28) bytes */
+/*
+ * When creating the index block, we place the update sequence array at this
+ * offset, i.e. before we start with the index entries. This also makes sense,
+ * otherwise we could run into problems with the update sequence array
+ * containing in itself the last two bytes of a sector which would mean that
+ * multi sector transfer protection wouldn't work. As you can't protect data
+ * by overwriting it since you then can't get it back...
+ * When reading use the data from the ntfs record header.
+ */
+} __attribute__ ((__packed__)) INDEX_BLOCK;
+
+#define _INR(X)  SC(inr,X)
+
+typedef INDEX_BLOCK INDEX_ALLOCATION;
+
+/*
+ * The system file FILE_Extend/$Reparse contains an index named $R listing
+ * all reparse points on the volume. The index entry keys are as defined
+ * below. Note, that there is no index data associated with the index entries.
+ *
+ * The index entries are sorted by the index key file_id. The collation rule is
+ * COLLATION_NTOFS_ULONGS. FIXME: Verify whether the reparse_tag is not the
+ * primary key / is not a key at all. (AIA)
+ */
+typedef struct {
+	u32 reparse_tag;	/* Reparse point type (inc. flags). */
+	MFT_REF file_id;	/* Mft record of the file containing the
+				   reparse point attribute. */
+} __attribute__ ((__packed__)) REPARSE_INDEX_KEY;
+
+/*
+ * Quota flags (32-bit).
+ */
+typedef enum {
+	/* The user quota flags. Names explain meaning. */
+	QUOTA_FLAG_DEFAULT_LIMITS	= const_cpu_to_le32(0x00000001),
+	QUOTA_FLAG_LIMIT_REACHED	= const_cpu_to_le32(0x00000002),
+	QUOTA_FLAG_ID_DELETED		= const_cpu_to_le32(0x00000004),
+
+	QUOTA_FLAG_USER_MASK		= const_cpu_to_le32(0x00000007),
+		/* Bit mask for user quota flags. */
+	
+	/* These flags are only present in the quota defaults index entry,
+	   i.e. in the entry where owner_id = QUOTA_DEFAULTS_ID. */
+	QUOTA_FLAG_TRACKING_ENABLED	= const_cpu_to_le32(0x00000010),
+	QUOTA_FLAG_ENFORCEMENT_ENABLED	= const_cpu_to_le32(0x00000020),
+	QUOTA_FLAG_TRACKING_REQUESTED	= const_cpu_to_le32(0x00000040),
+	QUOTA_FLAG_LOG_THRESHOLD	= const_cpu_to_le32(0x00000080),
+	QUOTA_FLAG_LOG_LIMIT		= const_cpu_to_le32(0x00000100),
+	QUOTA_FLAG_OUT_OF_DATE		= const_cpu_to_le32(0x00000200),
+	QUOTA_FLAG_CORRUPT		= const_cpu_to_le32(0x00000400),
+	QUOTA_FLAG_PENDING_DELETES	= const_cpu_to_le32(0x00000800),
+} QUOTA_FLAGS;
+
+/*
+ * The system file FILE_Extend/$Quota contains two indexes $O and $Q. Quotas
+ * are on a per volume and per user basis.
+ *
+ * The $Q index contains one entry for each existing user_id on the volume. The
+ * index key is the user_id of the user/group owning this quota control entry,
+ * i.e. the key is the owner_id. The user_id of the owner of a file, i.e. the 
+ * owner_id, is found in the standard information attribute. The collation rule
+ * for $Q is COLLATION_NTOFS_ULONG.
+ *
+ * The $O index contains one entry for each user/group who has been assigned
+ * a quota on that volume. The index key holds the SID of the user_id the
+ * entry belongs to, i.e. the owner_id. The collation rule for $O is
+ * COLLATION_NTOFS_SID.
+ *
+ * The $O index entry data is the user_id of the user corresponding to the SID.
+ * This user_id is used as an index into $Q to find the quota control entry
+ * associated with the SID.
+ *
+ * The $Q index entry data is the quota control entry and is defined below.
+ */
+typedef struct {
+	u32 version;		/* Currently equals 2. */
+	QUOTA_FLAGS flags;	/* Flags describing this quota entry. */
+	u64 bytes_used;		/* How many bytes of the quota are in use. */
+	s64 change_time;	/* Last time this quota entry was changed. */
+	s64 threshold;		/* Soft quota (-1 if not limited). */
+	s64 limit;		/* Hard quota (-1 if not limited). */
+	s64 exceeded_time;	/* How long the soft quota has been exceeded. */
+	SID sid;		/* The SID of the user/object associated with
+				   this quota entry. Equals zero for the quota
+				   defaults entry. */
+} __attribute__ ((__packed__)) QUOTA_CONTROL_ENTRY;
+
+/*
+ * Predefined owner_id values (32-bit).
+ */
+typedef enum {
+	QUOTA_INVALID_ID	= const_cpu_to_le32(0x00000000),
+	QUOTA_DEFAULTS_ID	= const_cpu_to_le32(0x00000001),
+	QUOTA_FIRST_USER_ID	= const_cpu_to_le32(0x00000100),
+} PREDEFINED_OWNER_IDS;
+
+/*
+ * Index entry flags (16-bit).
+ */
+typedef enum {
+	INDEX_ENTRY_NODE = const_cpu_to_le16(1), /* This entry contains a sub-node,
+					      i.e. a reference to an index
+					      block in form of a virtual
+					      cluster number (see below). */
+	INDEX_ENTRY_END  = const_cpu_to_le16(2), /* This signifies the last entry in
+					      an index block. The index entry
+					      does not represent a file but it
+					      can point to a sub-node. */
+	INDEX_ENTRY_SPACE_FILLER = 0xffff, /* Just to force 16-bit width. */
+} __attribute__ ((__packed__)) INDEX_ENTRY_FLAGS;
+
+/*
+ * This the index entry header (see below).
+ */
+typedef struct {
+/*  0*/	union {		/* Only valid when INDEX_ENTRY_END is not set. */
+		MFT_REF indexed_file;		/* The mft reference of the file
+						   described by this index
+						   entry. Used for directory
+						   indexes. */
+		struct { /* Used for views/indexes to find the entry's data. */
+			u16 data_offset;	/* Data byte offset from this
+						   INDEX_ENTRY. Follows the
+						   index key. */
+			u16 data_length;	/* Data length in bytes. */
+			u32 reservedV;		/* Reserved (zero). */
+		} SN(iev) __attribute__ ((__packed__));
+	} SN(iif) __attribute__ ((__packed__));
+/*  8*/	u16 length;		 /* Byte size of this index entry, multiple of
+				    8-bytes. */
+/* 10*/	u16 key_length;		 /* Byte size of the key value, which is in the
+				    index entry. It follows field reserved. Not
+				    multiple of 8-bytes. */
+/* 12*/	INDEX_ENTRY_FLAGS flags; /* Bit field of INDEX_ENTRY_* flags. */
+/* 14*/	u16 reserved;		 /* Reserved/align to 8-byte boundary. */
+/* sizeof() = 16 bytes */
+} __attribute__ ((__packed__)) INDEX_ENTRY_HEADER;
+
+#define _IIF(X)  SC(ieh.iif,X)
+#define _IEV(X)  SC(iif.iev,X)
+
+/*
+ * This is an index entry. A sequence of such entries follows each INDEX_HEADER
+ * structure. Together they make up a complete index. The index follows either
+ * an index root attribute or an index allocation attribute.
+ *
+ * NOTE: Before NTFS 3.0 only filename attributes were indexed.
+ */
+typedef struct {
+/*  0*/ INDEX_ENTRY_HEADER SN(ieh);	/* The index entry header (see above). */
+/* 16*/	union {		/* The key of the indexed attribute. NOTE: Only present
+			   if INDEX_ENTRY_END bit in flags is not set. NOTE: On
+			   NTFS versions before 3.0 the only valid key is the
+			   FILE_NAME_ATTR. On NTFS 3.0+ the following
+			   additional index keys are defined: */
+		FILE_NAME_ATTR file_name;/* $I30 index in directories. */
+		SII_INDEX_KEY sii;	/* $SII index in $Secure. */
+		SDH_INDEX_KEY sdh;	/* $SDH index in $Secure. */
+		GUID object_id;		/* $O index in FILE_Extend/$ObjId: The
+					   object_id of the mft record found in
+					   the data part of the index. */
+		REPARSE_INDEX_KEY SN(iri);	/* $R index in FILE_Extend/$Reparse. */
+		SID sid;		/* $O index in FILE_Extend/$Quota:
+					   SID of the owner of the user_id. */
+		u32 owner_id;		/* $Q index in FILE_Extend/$Quota:
+					   user_id of the owner of the quota
+					   control entry in the data part of
+					   the index. */
+	} __attribute__ ((__packed__)) key;
+	/* The (optional) index data is inserted here when creating. */
+	// VCN vcn;	/* If INDEX_ENTRY_NODE bit in flags is set, the last
+	//		   eight bytes of this index entry contain the virtual
+	//		   cluster number of the index block that holds the
+	//		   entries immediately preceding the current entry (the
+	//		   vcn references the corresponding cluster in the data
+	//		   of the non-resident index allocation attribute). If
+	//		   the key_length is zero, then the vcn immediately
+	//		   follows the INDEX_ENTRY_HEADER. Regardless of
+	//		   key_length, the address of the 8-byte boundary
+	//		   alligned vcn of INDEX_ENTRY{_HEADER} *ie is given by
+	//		   (char*)ie + le16_to_cpu(ie*)->length) - sizeof(VCN),
+	//		   where sizeof(VCN) can be hardcoded as 8 if wanted. */
+} __attribute__ ((__packed__)) INDEX_ENTRY;
+
+#define _IEH(X)  SC(ieh,X)
+#define _IRI(X)  SC(key.iri,X)
+
+/*
+ * Attribute: Bitmap (0xb0).
+ *
+ * Contains an array of bits (aka a bitfield).
+ *
+ * When used in conjunction with the index allocation attribute, each bit
+ * corresponds to one index block within the index allocation attribute. Thus
+ * the number of bits in the bitmap * index block size / cluster size is the
+ * number of clusters in the index allocation attribute.
+ */
+typedef struct {
+	u8 bitmap[0];			/* Array of bits. */
+} __attribute__ ((__packed__)) BITMAP_ATTR;
+
+/*
+ * The reparse point tag defines the type of the reparse point. It also
+ * includes several flags, which further describe the reparse point.
+ *
+ * The reparse point tag is an unsigned 32-bit value divided in three parts:
+ *
+ * 1. The least significant 16 bits (i.e. bits 0 to 15) specifiy the type of
+ *    the reparse point.
+ * 2. The 13 bits after this (i.e. bits 16 to 28) are reserved for future use.
+ * 3. The most significant three bits are flags describing the reparse point.
+ *    They are defined as follows:
+ *	bit 29: Name surrogate bit. If set, the filename is an alias for
+ *		another object in the system.
+ * 	bit 30: High-latency bit. If set, accessing the first byte of data will
+ *		be slow. (E.g. the data is stored on a tape drive.)
+ * 	bit 31: Microsoft bit. If set, the tag is owned by Microsoft. User
+ *		defined tags have to use zero here.
+ */
+typedef enum {
+	IO_REPARSE_TAG_IS_ALIAS		= const_cpu_to_le32(0x20000000),
+	IO_REPARSE_TAG_IS_HIGH_LATENCY	= const_cpu_to_le32(0x40000000),
+	IO_REPARSE_TAG_IS_MICROSOFT	= const_cpu_to_le32(0x80000000),
+	
+	IO_REPARSE_TAG_RESERVED_ZERO	= const_cpu_to_le32(0x00000000),
+	IO_REPARSE_TAG_RESERVED_ONE	= const_cpu_to_le32(0x00000001),
+	IO_REPARSE_TAG_RESERVED_RANGE	= const_cpu_to_le32(0x00000001),
+
+	IO_REPARSE_TAG_NSS		= const_cpu_to_le32(0x68000005),
+	IO_REPARSE_TAG_NSS_RECOVER	= const_cpu_to_le32(0x68000006),
+	IO_REPARSE_TAG_SIS		= const_cpu_to_le32(0x68000007),
+	IO_REPARSE_TAG_DFS		= const_cpu_to_le32(0x68000008),
+
+	IO_REPARSE_TAG_MOUNT_POINT	= const_cpu_to_le32(0x88000003),
+
+	IO_REPARSE_TAG_HSM		= const_cpu_to_le32(0xa8000004),
+
+	IO_REPARSE_TAG_SYMBOLIC_LINK	= const_cpu_to_le32(0xe8000000),
+
+	IO_REPARSE_TAG_VALID_VALUES	= const_cpu_to_le32(0xe000ffff),
+} PREDEFINED_REPARSE_TAGS;
+
+/*
+ * Attribute: Reparse point (0xc0).
+ *
+ * NOTE: Can be resident or non-resident.
+ */
+typedef struct {
+	u32 reparse_tag;		/* Reparse point type (inc. flags). */
+	u16 reparse_data_length;	/* Byte size of reparse data. */
+	u16 reserved;			/* Align to 8-byte boundary. */
+	u8 reparse_data[0];		/* Meaning depends on reparse_tag. */
+} __attribute__ ((__packed__)) REPARSE_POINT;
+
+/*
+ * Attribute: Extended attribute (EA) information (0xd0).
+ *
+ * NOTE: Always resident. (Is this true???)
+ */
+typedef struct {
+	u16 ea_length;		/* Byte size of the packed extended
+				   attributes. */
+	u16 need_ea_count;	/* The number of extended attributes which have
+				   the NEED_EA bit set. */
+	u32 ea_query_length;	/* Byte size of the buffer required to query
+				   the extended attributes when calling
+				   ZwQueryEaFile() in Windows NT/2k. I.e. the
+				   byte size of the unpacked extended
+				   attributes. */
+} __attribute__ ((__packed__)) EA_INFORMATION;
+
+/*
+ * Extended attribute flags (8-bit).
+ */
+typedef enum {
+	NEED_EA	= 0x80,
+} __attribute__ ((__packed__)) EA_FLAGS;
+
+/*
+ * Attribute: Extended attribute (EA) (0xe0).
+ *
+ * NOTE: Always non-resident. (Is this true?)
+ * 
+ * Like the attribute list and the index buffer list, the EA attribute value is 
+ * a sequence of EA_ATTR variable length records.
+ *
+ * FIXME: It appears weird that the EA name is not unicode. Is it true?
+ */
+typedef struct {
+	u32 next_entry_offset;	/* Offset to the next EA_ATTR. */
+	EA_FLAGS flags;		/* Flags describing the EA. */
+	u8 ea_name_length;	/* Length of the name of the EA in bytes. */
+	u16 ea_value_length;	/* Byte size of the EA's value. */
+	u8 ea_name[0];		/* Name of the EA. */
+	u8 ea_value[0];		/* The value of the EA. Immediately follows
+				   the name. */
+} __attribute__ ((__packed__)) EA_ATTR;
+
+/*
+ * Attribute: Property set (0xf0).
+ *
+ * Intended to support Native Structure Storage (NSS) - a feature removed from
+ * NTFS 3.0 during beta testing.
+ */
+typedef struct {
+	/* Irrelevant as feature unused. */
+} __attribute__ ((__packed__)) PROPERTY_SET;
+
+/*
+ * Attribute: Logged utility stream (0x100).
+ *
+ * NOTE: Can be resident or non-resident.
+ *
+ * Operations on this attribute are logged to the journal ($LogFile) like
+ * normal metadata changes.
+ *
+ * Used by the Encrypting File System (EFS). All encrypted files have this
+ * attribute with the name $EFS.
+ */
+typedef struct {
+	/* Can be anything the creator chooses. */
+	/* EFS uses it as follows: */
+	// FIXME: Type this info, verifying it along the way. (AIA)
+} __attribute__ ((__packed__)) LOGGED_UTILITY_STREAM, EFS_ATTR;
+
+#endif /* _LINUX_NTFS_LAYOUT_H */
+

fs/ntfs/macros.h

-/*
- * macros.h
- *
- * Copyright (C) 1995 Martin von Lwis
- * Copyright (C) 1996 Rgis Duchesne
- * Copyright (c) 2001 Anton Altaparmakov
- */
-#include <linux/ntfs_fs_i.h>
-#include <linux/fs.h>
-#include <asm/page.h>
-
-#define NTFS_FD(vol)		((vol)->u.fd)
-
-#define NTFS_SB(vol)		((struct super_block*)(vol)->sb)
-#define NTFS_SB2VOL(sb)         (&(sb)->u.ntfs_sb)
-#define NTFS_INO2VOL(ino)	(&((ino)->i_sb->u.ntfs_sb))
-static inline struct ntfs_i *ntfs_i(struct inode *inode)
-{
-	return list_entry(inode, struct ntfs_i, vfs_inode);
-}
-#define NTFS_I(ino)     (&ntfs_i(ino)->n)
-static inline struct inode *VFS_I(struct ntfs_inode_info *ntfs_ino)
-{
-	return &list_entry(ntfs_ino, struct ntfs_i, n)->vfs_inode;
-}
-
-#define IS_MAGIC(a,b)		(*(int*)(a) == *(int*)(b))
-#define IS_MFT_RECORD(a)	IS_MAGIC((a),"FILE")
-#define IS_INDEX_RECORD(a)	IS_MAGIC((a),"INDX")
-
-/* 'NTFS' in little endian */
-#define NTFS_SUPER_MAGIC	0x5346544E
-
-#define NTFS_AFLAG_RO           1
-#define NTFS_AFLAG_HIDDEN       2
-#define NTFS_AFLAG_SYSTEM       4
-#define NTFS_AFLAG_ARCHIVE      20
-#define NTFS_AFLAG_COMPRESSED   0x800
-#define NTFS_AFLAG_DIR          0x10000000
-

fs/ntfs/malloc.h

+/*
+ * malloc.h - NTFS kernel memory handling. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_MALLOC_H
+#define _LINUX_NTFS_MALLOC_H
+
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+
+/**
+ * vmalloc_nofs - allocate any pages but don't allow calls into fs layer
+ * @size:	number of bytes to allocate
+ *
+ * Allocate any pages but don't allow calls into fs layer. Return allocated
+ * memory or NULL if insufficient memory.
+ */
+static inline void *vmalloc_nofs(unsigned long size)
+{
+	if (likely(size >> PAGE_SHIFT < num_physpages))
+		return __vmalloc(size, GFP_NOFS | __GFP_HIGHMEM, PAGE_KERNEL);
+	return NULL;
+}
+
+/**
+ * ntfs_malloc_nofs - allocate memory in multiples of pages
+ * @size	number of bytes to allocate
+ *
+ * Allocates @size bytes of memory, rounded up to multiples of PAGE_SIZE and
+ * returns a pointer to the allocated memory.
+ *
+ * If there was insufficient memory to complete the request, return NULL.
+ */
+static inline void *ntfs_malloc_nofs(unsigned long size)
+{
+	if (likely(size <= PAGE_SIZE)) {
+		if (likely(size)) {
+			/* kmalloc() has per-CPU caches so if faster for now. */
+			return kmalloc(PAGE_SIZE, GFP_NOFS);
+			/* return (void *)__get_free_page(GFP_NOFS |
+					__GFP_HIGHMEM); */
+		}
+		BUG();
+	}
+	if (likely(size >> PAGE_SHIFT < num_physpages))
+		return __vmalloc(size, GFP_NOFS | __GFP_HIGHMEM, PAGE_KERNEL);
+	return NULL;
+}
+
+static inline void ntfs_free(void *addr)
+{
+	if (likely((unsigned long)addr < VMALLOC_START)) {
+		return kfree(addr);
+		/* return free_page((unsigned long)addr); */
+	}
+	vfree(addr);
+}
+
+#endif /* _LINUX_NTFS_MALLOC_H */
+

fs/ntfs/mft.c

+/**
+ * mft.c - NTFS kernel mft record operations. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/locks.h>
+#include <linux/swap.h>
+
+#include "ntfs.h"
+
+#define MAX_BUF_PER_PAGE (PAGE_CACHE_SIZE / 512)
+
+/**
+ * __format_mft_record - initialize an empty mft record
+ * @m:		mapped, pinned and locked for writing mft record
+ * @size:	size of the mft record
+ * @rec_no:	mft record number / inode number
+ *
+ * Private function to initialize an empty mft record. Use one of the two
+ * provided format_mft_record() functions instead.
+ */
+static void __format_mft_record(MFT_RECORD *m, const int size,
+		const unsigned long rec_no)
+{
+	ATTR_RECORD *a;
+
+	memset(m, 0, size);
+	m->_MNR(magic) = magic_FILE;
+	/* Aligned to 2-byte boundary. */
+	m->_MNR(usa_ofs) = cpu_to_le16((sizeof(MFT_RECORD) + 1) & ~1);
+	m->_MNR(usa_count) = cpu_to_le16(size / NTFS_BLOCK_SIZE + 1);
+	/* Set the update sequence number to 1. */
+	*(u16*)((char*)m + ((sizeof(MFT_RECORD) + 1) & ~1)) = cpu_to_le16(1);
+	m->lsn = cpu_to_le64(0LL);
+	m->sequence_number = cpu_to_le16(1);
+	m->link_count = cpu_to_le16(0);
+	/* Aligned to 8-byte boundary. */
+	m->attrs_offset = cpu_to_le16((le16_to_cpu(m->_MNR(usa_ofs)) +
+			(le16_to_cpu(m->_MNR(usa_count)) << 1) + 7) & ~7);
+	m->flags = cpu_to_le16(0);
+	/*
+	 * Using attrs_offset plus eight bytes (for the termination attribute),
+	 * aligned to 8-byte boundary.
+	 */
+	m->bytes_in_use = cpu_to_le32((le16_to_cpu(m->attrs_offset) + 8 + 7) &
+			~7);
+	m->bytes_allocated = cpu_to_le32(size);
+	m->base_mft_record = cpu_to_le64((MFT_REF)0);
+	m->next_attr_instance = cpu_to_le16(0);
+	a = (ATTR_RECORD*)((char*)m + le16_to_cpu(m->attrs_offset));
+	a->type = AT_END;
+	a->length = cpu_to_le32(0);
+}
+
+/**
+ * format_mft_record2 - initialize an empty mft record
+ * @vfs_sb:	vfs super block of volume
+ * @inum:	mft record number / inode number to format
+ * @mft_rec:	mapped, pinned and locked mft record (optional)
+ *
+ * Initialize an empty mft record. This is used when extending the MFT.
+ *
+ * If @mft_rec is NULL, we call map_mft_record() to obtain the record and we
+ * unmap it again when finished.
+ *
+ * We return 0 on success or -errno on error.
+ */
+#if 0
+// Can't do this as iget_map_mft_record no longer exists...
+int format_mft_record2(struct super_block *vfs_sb, const unsigned long inum,
+		MFT_RECORD *mft_rec)
+{
+	MFT_RECORD *m;
+	ntfs_inode *ni;
+
+	if (mft_rec)
+		m = mft_rec;
+	else {
+		m = iget_map_mft_record(WRITE, vfs_sb, inum, &ni);
+		if (IS_ERR(m))
+			return PTR_ERR(m);
+	}
+	__format_mft_record(m, NTFS_SB(vfs_sb)->mft_record_size, inum);
+	if (!mft_rec) {
+		// TODO: dirty mft record
+		unmap_mft_record(WRITE, ni);
+		// TODO: Do stuff to get rid of the ntfs_inode
+	}
+	return 0;
+}
+#endif
+
+/**
+ * format_mft_record - initialize an empty mft record
+ * @ni:		ntfs inode of mft record
+ * @mft_rec:	mapped, pinned and locked mft record (optional)
+ *
+ * Initialize an empty mft record. This is used when extending the MFT.
+ *
+ * If @mft_rec is NULL, we call map_mft_record() to obtain the
+ * record and we unmap it again when finished.
+ *
+ * We return 0 on success or -errno on error.
+ */
+int format_mft_record(ntfs_inode *ni, MFT_RECORD *mft_rec)
+{
+	MFT_RECORD *m;
+
+	if (mft_rec)
+		m = mft_rec;
+	else {
+		m = map_mft_record(WRITE, ni);
+		if (IS_ERR(m))
+			return PTR_ERR(m);
+	}
+	__format_mft_record(m, ni->vol->mft_record_size, ni->mft_no);
+	if (!mft_rec)
+		unmap_mft_record(WRITE, ni);
+	return 0;
+}
+
+/**
+ * ntfs_mft_readpage - read a page of the data attribute of $MFT
+ * @file:	open file to which the page @page belongs or NULL
+ * @page:	page cache page to fill with data
+ *
+ * Readpage method for the VFS address space operations.
+ *
+ * ntfs_mft_readpage() reads the page specified by @page and returns 0 on
+ * success or -EIO on error.
+ *
+ * Note, we only setup asynchronous I/O on the page and return. I/O completion
+ * is signalled via our asynchronous I/O completion handler
+ * end_buffer_read_index_async().
+ */
+static int ntfs_mft_readpage(struct file *file, struct page *page)
+{
+	VCN vcn;
+	LCN lcn;
+	struct inode *vi;
+	ntfs_inode *ni;
+	struct super_block *sb;
+	ntfs_volume *vol;
+	struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
+	sector_t iblock, lblock;
+	unsigned int blocksize, blocks,vcn_ofs;
+	int i, nr;
+	unsigned char blocksize_bits;
+
+	/* The page must be locked. */
+	if (!PageLocked(page))
+		PAGE_BUG(page);
+	/* Get the VFS and ntfs inodes as well as the super blocks for page. */
+	vi = page->mapping->host;
+	ni = NTFS_I(vi);
+	sb = vi->i_sb;
+	vol = NTFS_SB(sb);
+
+	blocksize = sb->s_blocksize;
+	blocksize_bits = sb->s_blocksize_bits;
+
+	if (!page->buffers)
+		create_empty_buffers(page, blocksize);
+
+	blocks = PAGE_CACHE_SIZE >> blocksize_bits;
+	iblock = page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
+	lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits;
+
+	bh = head = page->buffers;
+	BUG_ON(!bh);
+
+#ifdef DEBUG
+	if (!ni->run_list.rl)
+		panic("NTFS: $MFT/$DATA run list has been unmapped! This is a "
+				"very serious bug! Cannot continue...");
+#endif
+
+	nr = i = 0;
+	/* Loop through all the buffers in the page. */
+	do {
+		if (buffer_mapped(bh))
+			BUG();
+		/* Is the block within the allowed limits? */
+		if (iblock < lblock) {
+			/* Convert iblock into corresponding vcn and offset. */
+			vcn = (VCN)iblock << blocksize_bits >>
+					vol->cluster_size_bits;
+			vcn_ofs = ((VCN)iblock << blocksize_bits) &
+					vol->cluster_size_mask;
+			/* Convert the vcn to the corresponding lcn. */
+			read_lock(&ni->run_list.lock);
+			lcn = vcn_to_lcn(ni->run_list.rl, vcn);
+			read_unlock(&ni->run_list.lock);
+			if (lcn >= 0) {
+				/* Setup buffer head to correct block. */
+				bh->b_dev = vi->i_dev;
+				bh->b_blocknr = ((lcn << vol->cluster_size_bits)
+						+ vcn_ofs) >> blocksize_bits;
+				bh->b_state |= (1UL << BH_Mapped);
+				arr[nr++] = bh;
+				continue;
+			}
+			ntfs_error(sb, "vcn_to_lcn(vcn = 0x%Lx) failed with "
+					"error code 0x%Lx.", (long long)vcn,
+					(long long)-lcn);
+			// FIXME: Depending on vol->on_errors, do something.
+		}
+		/*
+		 * Either iblock was outside lblock limits or vcn_to_lcn()
+		 * returned error. Just zero that portion of the page and set
+		 * the buffer uptodate.
+		 */
+		bh->b_dev = vi->i_dev;
+		bh->b_blocknr = -1UL;
+		bh->b_state &= ~(1UL << BH_Mapped);
+		memset(kmap(page) + i * blocksize, 0, blocksize);
+		flush_dcache_page(page);
+		kunmap(page);
+		set_bit(BH_Uptodate, &bh->b_state);
+	} while (i++, iblock++, (bh = bh->b_this_page) != head);
+
+	/* Check we have at least one buffer ready for io. */
+	if (nr) {
+		/* Lock the buffers. */
+		for (i = 0; i < nr; i++) {
+			struct buffer_head *tbh = arr[i];
+			lock_buffer(tbh);
+			tbh->b_end_io = end_buffer_read_index_async;
+			mark_buffer_async(tbh, 1);
+		}
+		/* And start io on the buffers. */
+		for (i = 0; i < nr; i++)
+			submit_bh(READ, arr[i]);
+		return 0;
+	}
+	/* We didn't schedule any io on any of the buffers. */
+	ntfs_error(sb, "No I/O was scheduled on any buffers. Page I/O error.");
+	SetPageError(page);
+	UnlockPage(page);
+	return -EIO;
+}
+
+/**
+ * ntfs_mft_aops - address space operations for access to $MFT
+ *
+ * Address space operations for access to $MFT. This allows us to simply use
+ * read_cache_page() in map_mft_record().
+ */
+struct address_space_operations ntfs_mft_aops = {
+	writepage:	NULL,			/* Write dirty page to disk. */
+	readpage:	ntfs_mft_readpage,	/* Fill page with data. */
+	sync_page:	block_sync_page,	/* Currently, just unplugs the
+						   disk request queue. */
+	prepare_write:	NULL,			/* . */
+	commit_write:	NULL,			/* . */
+	bmap:		NULL,			/* Needed for FIBMAP.
+						   Don't use it. */
+	flushpage:	NULL,			/* . */
+	releasepage:	NULL,			/* . */
+#ifdef KERNEL_HAS_O_DIRECT
+	direct_IO:	NULL,			/* . */
+#endif
+};
+
+/**
+ * map_mft_record_page - map the page in which a specific mft record resides
+ * @ni:		ntfs inode whose mft record page to map
+ *
+ * This maps the page in which the mft record of the ntfs inode @ni is situated
+ * and returns a pointer to the mft record within the mapped page.
+ *
+ * Return value needs to be checked with IS_ERR() and if that is true PTR_ERR()
+ * contains the negative error code returned.
+ */
+static inline MFT_RECORD *map_mft_record_page(ntfs_inode *ni)
+{
+	ntfs_volume *vol = ni->vol;
+	struct inode *mft_vi = vol->mft_ino;
+	struct page *page;
+	unsigned long index, ofs, end_index;
+
+	BUG_ON(atomic_read(&ni->mft_count) || ni->page);
+	/*
+	 * The index into the page cache and the offset within the page cache
+	 * page of the wanted mft record. FIXME: We need to check for
+	 * overflowing the unsigned long, but I don't think we would ever get
+	 * here if the volume was that big...
+	 */
+	index = ni->mft_no << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
+	ofs = (ni->mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
+
+	/* The maximum valid index into the page cache for $MFT's data. */
+	end_index = mft_vi->i_size >> PAGE_CACHE_SHIFT;
+
+	/* If the wanted index is out of bounds the mft record doesn't exist. */
+	if (index >= end_index) {
+		if (index > end_index || (mft_vi->i_size & ~PAGE_CACHE_MASK) <
+				ofs + vol->mft_record_size) {
+			page = ERR_PTR(-ENOENT);
+			goto up_err_out;
+		}
+	}
+	/* Read, map, and pin the page. */
+	page = ntfs_map_page(mft_vi->i_mapping, index);
+	if (!IS_ERR(page)) {
+		/* Pin the mft record mapping in the ntfs_inode. */
+		atomic_inc(&ni->mft_count);
+
+		/* Setup the references in the ntfs_inode. */
+		ni->page = page;
+		ni->page_ofs = ofs;
+
+		return page_address(page) + ofs;
+	}
+up_err_out:
+	/* Just in case... */
+	ni->page = NULL;
+	ni->page_ofs = 0;
+
+	ntfs_error(vol->sb, "Failed with error code %lu.", -PTR_ERR(page));
+	return (void*)page;
+}
+
+/**
+ * unmap_mft_record_page - unmap the page in which a specific mft record resides
+ * @ni:		ntfs inode whose mft record page to unmap
+ *
+ * This unmaps the page in which the mft record of the ntfs inode @ni is
+ * situated and returns. This is a NOOP if highmem is not configured.
+ *
+ * The unmap happens via ntfs_unmap_page() which in turn decrements the use
+ * count on the page thus releasing it from the pinned state.
+ *
+ * We do not actually unmap the page from memory of course, as that will be
+ * done by the page cache code itself when memory pressure increases or
+ * whatever.
+ */
+static inline void unmap_mft_record_page(ntfs_inode *ni)
+{
+	BUG_ON(atomic_read(&ni->mft_count) || !ni->page);
+	// TODO: If dirty, blah...
+	ntfs_unmap_page(ni->page);
+	ni->page = NULL;
+	ni->page_ofs = 0;
+	return;
+}
+
+/**
+ * map_mft_record - map, pin and lock an mft record
+ * @rw:		map for read (rw = READ) or write (rw = WRITE)
+ * @ni:		ntfs inode whose MFT record to map
+ *
+ * First, take the mrec_lock semaphore for reading or writing, depending on
+ * the value or @rw. We might now be sleeping, while waiting for the semaphore
+ * if it was already locked by someone else.
+ *
+ * Then increment the map reference count and return the mft. If this is the
+ * first invocation, the page of the record is first mapped using
+ * map_mft_record_page().
+ *
+ * This in turn uses ntfs_map_page() to get the page containing the wanted mft
+ * record (it in turn calls read_cache_page() which reads it in from disk if
+ * necessary, increments the use count on the page so that it cannot disappear
+ * under us and returns a reference to the page cache page).
+ *
+ * If read_cache_page() invokes ntfs_mft_readpage() to load the page from disk,
+ * it sets PG_locked and clears PG_uptodate on the page. Once I/O has
+ * completed and the post-read mst fixups on each mft record in the page have
+ * been performed, the page gets PG_uptodate set and PG_locked cleared (this is
+ * done in our asynchronous I/O completion handler end_buffer_read_mft_async()).
+ * ntfs_map_page() waits for PG_locked to become clear and checks if
+ * PG_uptodate is set and returns an error code if not. This provides
+ * sufficient protection against races when reading/using the page.
+ *
+ * However there is the write mapping to think about. Doing the above described
+ * checking here will be fine, because when initiating the write we will set
+ * PG_locked and clear PG_uptodate making sure nobody is touching the page
+ * contents. Doing the locking this way means that the commit to disk code in
+ * the page cache code paths is automatically sufficiently locked with us as
+ * we will not touch a page that has been locked or is not uptodate. The only
+ * locking problem then is them locking the page while we are accessing it.
+ *
+ * So that code will end up having to own the mrec_lock of all mft
+ * records/inodes present in the page before I/O can proceed. Grr. In that
+ * case we wouldn't need need to bother with PG_locked and PG_uptodate as
+ * nobody will be accessing anything without owning the mrec_lock semaphore.
+ * But we do need to use them because of the read_cache_page() invokation and
+ * the code becomes so much simpler this way that it is well worth it.
+ *
+ * The mft record is now ours and we return a pointer to it. You need to check
+ * the returned pointer with IS_ERR() and if that is true, PTR_ERR() will return
+ * the error code. The following error codes are defined:
+ * 	TODO: Fill in the possible error codes.
+ *
+ * NOTE: Caller is responsible for setting the mft record dirty before calling
+ * unmap_mft_record(). This is obviously only necessary if the caller really
+ * modified the mft record...
+ * Q: Do we want to recycle one of the VFS inode state bits instead?
+ * A: No, the inode ones mean we want to change the mft record, not we want to
+ * write it out.
+ */
+MFT_RECORD *map_mft_record(const int rw, ntfs_inode *ni)
+{
+	MFT_RECORD *m;
+
+	ntfs_debug("Entering for i_ino 0x%Lx, mapping for %s.",
+			(unsigned long long)ni->mft_no,
+			rw == READ ? "READ" : "WRITE");
+
+	/* Make sure the ntfs inode doesn't go away. */
+	atomic_inc(&ni->count);
+
+	/* Serialize access to this mft record. */
+	if (rw == READ)
+		down_read(&ni->mrec_lock);
+	else
+		down_write(&ni->mrec_lock);
+
+	/* If already mapped, bump reference count and return the mft record. */
+	if (atomic_read(&ni->mft_count)) {
+		BUG_ON(!ni->page);
+		atomic_inc(&ni->mft_count);
+		return page_address(ni->page) + ni->page_ofs;
+	}
+
+	/* Wasn't mapped. Map it now and return it if all was ok. */
+	m = map_mft_record_page(ni);
+	if (!IS_ERR(m))
+		return m;
+
+	/* Mapping failed. Release the mft record lock. */
+	if (rw == READ)
+		up_read(&ni->mrec_lock);
+	else
+		up_write(&ni->mrec_lock);
+
+	ntfs_error(ni->vol->sb, "Failed with error code %lu.", -PTR_ERR(m));
+
+	/* Release the ntfs inode and return the error code. */
+	atomic_dec(&ni->count);
+	return m;
+}
+
+/**
+ * iget_map_mft_record - iget, map, pin, lock an mft record
+ * @rw:		map for read (rw = READ) or write (rw = WRITE)
+ * @vfs_sb:	vfs super block of mounted volume
+ * @inum:	inode number / MFT record number whose mft record to map
+ * @vfs_ino:	output parameter which we set to the inode on successful return
+ *
+ * Does the same as map_mft_record(), except that it starts out only with the
+ * knowledge of the super block (@vfs_sb) and the mft record number which is of
+ * course the same as the inode number (@inum).
+ *
+ * On success, *@vfs_ino will contain a pointer to the inode structure of the
+ * mft record on return. On error return, *@vfs_ino is undefined.
+ *
+ * See map_mft_record() description for details and for a description of how
+ * errors are returned and what error codes are defined.
+ *
+ * IMPROTANT: The caller is responsible for calling iput(@vfs_ino) when
+ * finished with the inode, i.e. after unmap_mft_record() has been called. If
+ * that is omitted you will get busy inodes upon umount...
+ */
+#if 0
+// this is no longer possible. iget() cannot be called as we may be loading
+// an ntfs inode which will never have a corresponding vfs inode counter part.
+// this is not going to be pretty. )-:
+// we need our own hash for ntfs inodes now, ugh. )-:
+// not having vfs inodes associated with all ntfs inodes is a bad mistake I am
+// getting the impression. this will in the end turn out uglier than just
+// having iget_no_wait().
+// my only hope is that we can get away without this functionality in the driver
+// altogether. we are ok for extent inodes already because we only handle them
+// via map_extent_mft_record().
+// if we really need it, we could have a list or hash of "pure ntfs inodes"
+// to cope with this situation, so the lookup would be:
+// look for the inode and if not present look for pure ntfs inode and if not
+// present add a new pure ntfs inode. under this scheme extent inodes have to
+// also be added to the list/hash of pure inodes.
+MFT_RECORD *iget_map_mft_record(const int rw, struct super_block *vfs_sb,
+		const unsigned long inum, struct inode **vfs_ino)
+{
+	struct inode *inode;
+	MFT_RECORD *mrec;
+
+	/*
+	 * The corresponding iput() happens when clear_inode() is called on the
+	 * base mft record of this extent mft record.
+	 * When used on base mft records, caller has to perform the iput().
+	 */
+	inode = iget(vfs_sb, inum);
+	if (inode && !is_bad_inode(inode)) {
+		mrec = map_mft_record(rw, inode);
+		if (!IS_ERR(mrec)) {
+			ntfs_debug("Success for i_ino 0x%lx.", inum);
+			*vfs_ino = inode;
+			return mrec;
+		}
+	} else
+		mrec = ERR_PTR(-EIO);
+	if (inode)
+		iput(inode);
+	ntfs_debug("Failed for i_ino 0x%lx.", inum);
+	return mrec;
+}
+#endif
+
+/**
+ * unmap_mft_record - release a mapped mft record
+ * @rw:		unmap from read (@rw = READ) or write (@rw = WRITE)
+ * @ni:		ntfs inode whose MFT record to unmap
+ *
+ * First, decrement the mapping count and when it reaches zero unmap the mft
+ * record.
+ *
+ * Second, release the mrec_lock semaphore.
+ *
+ * The mft record is now released for others to get hold of.
+ *
+ * Finally, release the ntfs inode by decreasing the ntfs inode reference count.
+ *
+ * NOTE: If caller had the mft record mapped for write and has modified it, it
+ * is imperative to set the mft record dirty BEFORE calling unmap_mft_record().
+ *
+ * NOTE: This has to be done both for 'normal' mft records, and for extent mft
+ * records.
+ */
+void unmap_mft_record(const int rw, ntfs_inode *ni)
+{
+	struct page *page = ni->page;
+
+	BUG_ON(!atomic_read(&ni->mft_count) || !page);
+
+	ntfs_debug("Entering for mft_no 0x%Lx, unmapping from %s.",
+			(unsigned long long)ni->mft_no,
+			rw == READ ? "READ" : "WRITE");
+
+	/* Only release the actual page mapping if this is the last one. */
+	if (atomic_dec_and_test(&ni->mft_count))
+		unmap_mft_record_page(ni);
+
+	/* Release the semaphore. */
+	if (rw == READ)
+		up_read(&ni->mrec_lock);
+	else
+		up_write(&ni->mrec_lock);
+
+	/* Release the ntfs inode. */
+	atomic_dec(&ni->count);
+
+	/*
+	 * If pure ntfs_inode, i.e. no vfs inode attached, we leave it to
+	 * ntfs_clear_inode() in the extent inode case, and to the caller in
+	 * the non-extent, yet pure ntfs inode case, to do the actual tear
+	 * down of all structures and freeing of all allocated memory.
+	 */
+	return;
+}
+
+/**
+ * map_extent_mft_record - load an extent inode and attach it to its base
+ * @base_ni:	base ntfs inode
+ * @mref:	mft reference of the extent inode to load (in little endian)
+ * @ntfs_ino:	on successful return, pointer to the ntfs_inode structure
+ *
+ * Load the extent mft record @mref and attach it to its base inode @base_ni.
+ * Return the mapped extent mft record if IS_ERR(result) is false. Otherwise
+ * PTR_ERR(result) gives the negative error code.
+ *
+ * On successful return, @ntfs_ino contains a pointer to the ntfs_inode
+ * structure of the mapped extent inode.
+ *
+ * Note, we always map for READ. We consider this lock as irrelevant because
+ * the base inode will be write locked in all cases when we want to write to
+ * an extent inode which already gurantees that there is no-one else accessing
+ * the extent inode.
+ */
+MFT_RECORD *map_extent_mft_record(ntfs_inode *base_ni, MFT_REF mref,
+		ntfs_inode **ntfs_ino)
+{
+	MFT_RECORD *m;
+	ntfs_inode *ni = NULL;
+	ntfs_inode **extent_nis = NULL;
+	int i;
+	u64 mft_no = MREF_LE(mref);
+	u16 seq_no = MSEQNO_LE(mref);
+	BOOL destroy_ni = FALSE;
+
+	ntfs_debug("Mapping extent mft record 0x%Lx (base mft record 0x%Lx).",
+			(unsigned long long)mft_no,
+			(unsigned long long)base_ni->mft_no);
+	/* Make sure the base ntfs inode doesn't go away. */
+	atomic_inc(&base_ni->count);
+	/*
+	 * Check if this extent inode has already been added to the base inode,
+	 * in which case just return it. If not found, add it to the base
+	 * inode before returning it.
+	 */
+	down(&base_ni->extent_lock);
+	if (base_ni->nr_extents > 0) {
+		extent_nis = base_ni->_INE(extent_ntfs_inos);
+		for (i = 0; i < base_ni->nr_extents; i++) {
+			if (mft_no != extent_nis[i]->mft_no)
+				continue;
+			ni = extent_nis[i];
+			/* Make sure the ntfs inode doesn't go away. */
+			atomic_inc(&ni->count);
+			break;
+		}
+	}
+	if (ni) {
+		up(&base_ni->extent_lock);
+		atomic_dec(&base_ni->count);
+		/* We found the record; just have to map and return it. */
+		m = map_mft_record(READ, ni);
+		/* Map mft record increments this on success. */
+		atomic_dec(&ni->count);
+		if (!IS_ERR(m)) {
+			/* Verify the sequence number. */
+			if (le16_to_cpu(m->sequence_number) == seq_no) {
+				ntfs_debug("Done 1.");
+				*ntfs_ino = ni;
+				return m;
+			}
+			unmap_mft_record(READ, ni);
+			ntfs_error(base_ni->vol->sb, "Found stale extent mft "
+					"reference! Corrupt file system. "
+					"Run chkdsk.");
+			return ERR_PTR(-EIO);
+		}
+map_err_out:
+		ntfs_error(base_ni->vol->sb, "Failed to map extent "
+				"mft record, error code %ld.", -PTR_ERR(m));
+		return m;
+	}
+	/* Record wasn't there. Get a new ntfs inode and initialize it. */
+	ni = ntfs_new_inode(base_ni->vol->sb);
+	if (!ni) {
+		up(&base_ni->extent_lock);
+		atomic_dec(&base_ni->count);
+		return ERR_PTR(-ENOMEM);
+	}
+	ni->vol = base_ni->vol;
+	ni->mft_no = mft_no;
+	ni->seq_no = seq_no;
+	ni->nr_extents = -1;
+	ni->_INE(base_ntfs_ino) = base_ni;
+	/* Now map the record. */
+	m = map_mft_record(READ, ni);
+	if (IS_ERR(m)) {
+		up(&base_ni->extent_lock);
+		atomic_dec(&base_ni->count);
+		ntfs_clear_inode(ni);
+		goto map_err_out;
+	}
+	/* Verify the sequence number. */
+	if (le16_to_cpu(m->sequence_number) != seq_no) {
+		ntfs_error(base_ni->vol->sb, "Found stale extent mft "
+				"reference! Corrupt file system. Run chkdsk.");
+		destroy_ni = TRUE;
+		m = ERR_PTR(-EIO);
+		goto unm_err_out;
+	}
+	/* Attach extent inode to base inode, reallocating memory if needed. */
+	if (!(base_ni->nr_extents & ~3)) {
+		ntfs_inode **tmp;
+		int new_size = (base_ni->nr_extents + 4) * sizeof(ntfs_inode *);
+
+		tmp = (ntfs_inode **)kmalloc(new_size, GFP_NOFS);
+		if (!tmp) {
+			ntfs_error(base_ni->vol->sb, "Failed to allocate "
+					"internal buffer.");
+			destroy_ni = TRUE;
+			m = ERR_PTR(-ENOMEM);
+			goto unm_err_out;
+		}
+		if (base_ni->_INE(extent_ntfs_inos)) {
+			memcpy(tmp, base_ni->_INE(extent_ntfs_inos), new_size -
+					4 * sizeof(ntfs_inode *));
+			kfree(base_ni->_INE(extent_ntfs_inos));
+		}
+		base_ni->_INE(extent_ntfs_inos) = tmp;
+	}
+	base_ni->_INE(extent_ntfs_inos)[base_ni->nr_extents++] = ni;
+	up(&base_ni->extent_lock);
+	atomic_dec(&base_ni->count);
+	ntfs_debug("Done 2.");
+	*ntfs_ino = ni;
+	return m;
+unm_err_out:
+	unmap_mft_record(READ, ni);
+	up(&base_ni->extent_lock);
+	atomic_dec(&base_ni->count);
+	/*
+	 * If the extent inode was not attached to the base inode we need to
+	 * release it or we will leak memory.
+	 */
+	if (destroy_ni)
+		ntfs_clear_inode(ni);
+	return m;
+}
+

fs/ntfs/unistr.h → fs/ntfs/mft.h

 /*
- * unistr.h - Exports for unicode string handling. Part of the Linux-NTFS
- *	      project.
+ * mft.h - Defines for mft record handling in NTFS Linux kernel driver.
+ *	   Part of the Linux-NTFS project.
  *
- * Copyright (c) 2000,2001 Anton Altaparmakov.
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
  *
  * This program/include file is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as published
@@ -20,25 +20,28 @@
  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#ifndef _LINUX_NTFS_UNISTR_H
-#define _LINUX_NTFS_UNISTR_H
+#ifndef _LINUX_NTFS_MFT_H
+#define _LINUX_NTFS_MFT_H
 
-#include <linux/types.h>
-#include <linux/nls.h>
+#include <linux/fs.h>
 
-extern const __u8 legal_ansi_char_array[0x40];
+#include "inode.h"
 
-int ntfs_are_names_equal(wchar_t *s1, size_t s1_len,
-			  wchar_t *s2, size_t s2_len, int ic,
-			  wchar_t *upcase, __u32 upcase_size);
+extern int format_mft_record(ntfs_inode *ni, MFT_RECORD *m);
+//extern int format_mft_record2(struct super_block *vfs_sb,
+//		const unsigned long inum, MFT_RECORD *m);
 
-int ntfs_collate_names(wchar_t *upcase, __u32 upcase_len,
-		       wchar_t *name1, __u32 name1_len,
-		       wchar_t *name2, __u32 name2_len,
-		       int ic, int err_val);
+extern MFT_RECORD *map_mft_record(const int rw, ntfs_inode *ni);
+extern void unmap_mft_record(const int rw, ntfs_inode *ni);
 
-int ntfs_wcsncasecmp(wchar_t *s1, wchar_t *s2, size_t n,
-		     wchar_t *upcase, __u32 upcase_size);
+extern MFT_RECORD *map_extent_mft_record(ntfs_inode *base_ni, MFT_REF mref,
+		ntfs_inode **ntfs_ino);
 
-#endif /* defined _LINUX_NTFS_UNISTR_H */
+static inline void unmap_extent_mft_record(ntfs_inode *ni)
+{
+	unmap_mft_record(READ, ni);
+	return;
+}
+
+#endif /* _LINUX_NTFS_MFT_H */
 

fs/ntfs/mst.c

+/*
+ * mst.c - NTFS multi sector transfer protection handling code. Part of the
+ * 	   Linux-NTFS project.
+ *
+ * Copyright (c) 2001 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "ntfs.h"
+
+/**
+ * __post_read_mst_fixup - fast deprotect multi sector transfer protected data
+ * @b:		pointer to the data to deprotect
+ * @size:	size in bytes of @b
+ * 
+ * Perform the necessary post read multi sector transfer fixup, not checking for
+ * any errors. Defined inline for additional speed. 
+ */
+inline void __post_read_mst_fixup(NTFS_RECORD *b, const u32 size)
+{
+	u16 usa_ofs, usa_count;
+	u16 *usa_pos, *data_pos;
+
+	/* Setup the variables. */
+	usa_ofs = le16_to_cpu(b->usa_ofs);
+	usa_count = le16_to_cpu(b->usa_count) - 1;
+	/* Position of usn in update sequence array. */  
+	usa_pos = (u16*)b + usa_ofs/sizeof(u16);
+	/*
+	 * Position in protected data of first u16 that needs fixing up.
+	 */
+	data_pos = (u16*)b + NTFS_BLOCK_SIZE/sizeof(u16) - 1;
+        /* Fixup all sectors. */
+	while (usa_count--) {
+		/*
+		 * Increment position in usa and restore original data from
+		 * the usa into the data buffer.
+		 */
+		*data_pos = *(++usa_pos);
+                /* Increment position in data as well. */
+		data_pos += NTFS_BLOCK_SIZE/sizeof(u16);
+        }
+}
+
+/**
+ * post_read_mst_fixup - deprotect multi sector transfer protected data
+ * @b:		pointer to the data to deprotect
+ * @size:	size in bytes of @b
+ * 
+ * Perform the necessary post read multi sector transfer fixup and detect the
+ * presence of incomplete multi sector transfers. - In that case, overwrite the
+ * magic of the ntfs record header being processed with "BAAD" (in memory only!)
+ * and abort processing.
+ *
+ * Return 0 on success and -EINVAL on error ("BAAD" magic will be present).
+ *
+ * NOTE: We consider the absence / invalidity of an update sequence array to
+ * mean that the structure is not protected at all and hence doesn't need to
+ * be fixed up. Thus, we return success and not failure in this case. This is
+ * in contrast to pre_write_mst_fixup(), see below.
+ */
+int post_read_mst_fixup(NTFS_RECORD *b, const u32 size)
+{
+	u16 usa_ofs, usa_count, usn;
+	u16 *usa_pos, *data_pos;
+
+	/* Setup the variables. */
+	usa_ofs = le16_to_cpu(b->usa_ofs);
+	/* Decrement usa_count to get number of fixups. */
+	usa_count = le16_to_cpu(b->usa_count) - 1;
+	/* Size and alignement checks. */
+	if ( size & (NTFS_BLOCK_SIZE - 1)	||
+	     usa_ofs & 1			||
+	     usa_ofs + (usa_count * 2) > size	||
+	     (size >> NTFS_BLOCK_SIZE_BITS) != usa_count)
+		return 0;
+	/* Position of usn in update sequence array. */  
+	usa_pos = (u16*)b + usa_ofs/sizeof(u16);
+	/* 
+	 * The update sequence number which has to be equal to each of the
+	 * u16 values before they are fixed up. Note no need to care for
+	 * endianness since we are comparing and moving data for on disk
+	 * structures which means the data is consistent. - If it is 
+	 * consistenty the wrong endianness it doesn't make any difference.
+	 */
+	usn = *usa_pos;
+	/*
+	 * Position in protected data of first u16 that needs fixing up.
+	 */
+	data_pos = (u16*)b + NTFS_BLOCK_SIZE/sizeof(u16) - 1;
+        /*
+	 * Check for incomplete multi sector transfer(s).
+	 */
+	while (usa_count--) {
+                if (*data_pos != usn) {
+			/*
+			 * Incomplete multi sector transfer detected! )-:
+			 * Set the magic to "BAAD" and return failure.
+			 * Note that magic_BAAD is already converted to le32.
+			 */
+			b->magic = magic_BAAD;
+	                return -EINVAL;
+		}
+		data_pos += NTFS_BLOCK_SIZE/sizeof(u16);
+	}
+	/* Re-setup the variables. */
+	usa_count = le16_to_cpu(b->usa_count) - 1;
+	data_pos = (u16*)b + NTFS_BLOCK_SIZE/sizeof(u16) - 1;
+	/* Fixup all sectors. */
+	while (usa_count--) {
+		/*
+		 * Increment position in usa and restore original data from
+		 * the usa into the data buffer.
+		 */
+		*data_pos = *(++usa_pos);
+                /* Increment position in data as well. */
+		data_pos += NTFS_BLOCK_SIZE/sizeof(u16);
+        }
+	return 0;
+}
+
+/**
+ * pre_write_mst_fixup - apply multi sector transfer protection
+ * @b:		pointer to the data to protect
+ * @size:	size in bytes of @b
+ * 
+ * Perform the necessary pre write multi sector transfer fixup on the data
+ * pointer to by @b of @size.
+ *
+ * Return 0 if fixup applied (success) or -EINVAL if no fixup was performed
+ * (assumed not needed). This is in contrast to post_read_mst_fixup() above.
+ *
+ * NOTE: We consider the absence / invalidity of an update sequence array to
+ * mean that the structure is not subject to protection and hence doesn't need
+ * to be fixed up. This means that you have to create a valid update sequence
+ * array header in the ntfs record before calling this function, otherwise it
+ * will fail (the header needs to contain the position of the update seqeuence
+ * array together with the number of elements in the array). You also need to
+ * initialise the update sequence number before calling this function
+ * otherwise a random word will be used (whatever was in the record at that
+ * position at that time).
+ */
+int pre_write_mst_fixup(NTFS_RECORD *b, const u32 size)
+{
+	u16 usa_ofs, usa_count, usn;
+	u16 *usa_pos, *data_pos;
+
+	/* Sanity check + only fixup if it makes sense. */
+	if (!b || is_baad_record(b->magic) || is_hole_record(b->magic))
+		return -EINVAL;
+	/* Setup the variables. */
+	usa_ofs = le16_to_cpu(b->usa_ofs);
+	/* Decrement usa_count to get number of fixups. */
+	usa_count = le16_to_cpu(b->usa_count) - 1;
+	/* Size and alignement checks. */
+	if ( size & (NTFS_BLOCK_SIZE - 1)	||
+	     usa_ofs & 1			||
+	     usa_ofs + (usa_count * 2) > size	||
+	     (size >> NTFS_BLOCK_SIZE_BITS) != usa_count)
+		return -EINVAL;
+	/* Position of usn in update sequence array. */  
+	usa_pos = (u16*)((u8*)b + usa_ofs);
+	/*
+	 * Cyclically increment the update sequence number 
+	 * (skipping 0 and -1, i.e. 0xffff).
+	 */
+	usn = le16_to_cpup(usa_pos) + 1;
+	if (usn == 0xffff || !usn)
+		usn = 1;
+	usn = cpu_to_le16(usn);
+	*usa_pos = usn;
+	/* Position in data of first u16 that needs fixing up. */
+	data_pos = (u16*)b + NTFS_BLOCK_SIZE/sizeof(u16) - 1;
+        /* Fixup all sectors. */
+        while (usa_count--) {
+		/*
+		 * Increment the position in the usa and save the 
+		 * original data from the data buffer into the usa.
+		 */
+		*(++usa_pos) = *data_pos;
+		/* Apply fixup to data. */
+		*data_pos = usn;
+		/* Increment position in data as well. */
+		data_pos += NTFS_BLOCK_SIZE/sizeof(u16);
+        }
+	return 0;
+}
+

fs/ntfs/namei.c

+/*
+ * namei.c - NTFS kernel directory inode operations. Part of the Linux-NTFS
+ * 	     project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "ntfs.h"
+
+/**
+ * ntfs_lookup - find the inode represented by a dentry in a directory inode
+ * @dir_ino:	directory inode in which to look for the inode
+ * @dent:	dentry representing the inode to look for
+ *
+ * In short, ntfs_lookup() looks for the inode represented by the dentry @dent
+ * in the directory inode @dir_ino and if found attaches the inode to the
+ * dentry @dent.
+ *
+ * In more detail, the dentry @dent specifies which inode to look for by
+ * supplying the name of the inode in @dent->d_name.name. ntfs_lookup()
+ * converts the name to Unicode and walks the contents of the directory inode
+ * @dir_ino looking for the converted Unicode name. If the name is found in the
+ * directory, the corresponding inode is loaded by calling iget() on its inode
+ * number and the inode is associated with the dentry @dent via a call to
+ * d_add().
+ *
+ * If the name is not found in the directory, a NULL inode is inserted into the
+ * dentry @dent. The dentry is then termed a negative dentry.
+ *
+ * Only if an actual error occurs, do we return an error via ERR_PTR().
+ */
+static struct dentry *ntfs_lookup(struct inode *dir_ino, struct dentry *dent)
+{
+	ntfs_volume *vol = NTFS_SB(dir_ino->i_sb);
+	struct inode *dent_inode;
+	u64 mref;
+	unsigned long dent_ino;
+	uchar_t *uname;
+	int uname_len;
+
+	ntfs_debug("Looking up %s in directory inode 0x%lx.",
+			dent->d_name.name, dir_ino->i_ino);
+	/* Convert the name of the dentry to Unicode. */
+	uname_len = ntfs_nlstoucs(vol, dent->d_name.name, dent->d_name.len,
+			&uname);
+	if (uname_len < 0) {
+		ntfs_error(vol->sb, "Failed to convert name to Unicode.");
+		return ERR_PTR(uname_len);
+	}
+	mref = ntfs_lookup_inode_by_name(NTFS_I(dir_ino), uname, uname_len);
+	kmem_cache_free(ntfs_name_cache, uname);
+	if (!IS_ERR_MREF(mref)) {
+		dent_ino = (unsigned long)MREF(mref);
+		ntfs_debug("Found inode 0x%lx. Calling iget.", dent_ino);
+		dent_inode = iget(vol->sb, dent_ino);
+		if (dent_inode) {
+			/* Consistency check. */
+			if (MSEQNO(mref) == NTFS_I(dent_inode)->seq_no ||
+					dent_ino == FILE_MFT) {
+				d_add(dent, dent_inode);
+				ntfs_debug("Done.");
+				return NULL;
+			}
+			ntfs_error(vol->sb, "Found stale reference to inode "
+					"0x%Lx (reference sequence number = "
+					"0x%x, inode sequence number = 0x%x, "
+					"returning -EACCES. Run chkdsk.",
+					(unsigned long long)MREF(mref),
+					MSEQNO(mref),
+					NTFS_I(dent_inode)->seq_no);
+			iput(dent_inode);
+		} else
+			ntfs_error(vol->sb, "iget(0x%Lx) failed, returning "
+					"-EACCES.",
+					(unsigned long long)MREF(mref));
+		return ERR_PTR(-EACCES);
+	}
+	if (MREF_ERR(mref) == -ENOENT) {
+		ntfs_debug("Entry was not found, adding negative dentry.");
+		/* The dcache will handle negative entries. */
+		d_add(dent, NULL);
+		ntfs_debug("Done.");
+		return NULL;
+	}
+	ntfs_error(vol->sb, "ntfs_lookup_ino_by_name() failed with error "
+			"code %i.", -MREF_ERR(mref));
+	return ERR_PTR(MREF_ERR(mref));
+}
+
+struct inode_operations ntfs_dir_inode_ops = {
+	create:		NULL,		/* . */
+	lookup:		ntfs_lookup,	/* lookup directory. */
+	link:		NULL,		/* . */
+	unlink:		NULL,		/* . */
+	symlink:	NULL,		/* . */
+	mkdir:		NULL,		/* . */
+	rmdir:		NULL,		/* . */
+	mknod:		NULL,		/* . */
+	rename:		NULL,		/* . */
+	readlink:	NULL,		/* . */
+	follow_link:	NULL,		/* . */
+	truncate:	NULL,		/* . */
+	permission:	NULL,		/* . */
+	revalidate:	NULL,		/* . */
+	setattr:	NULL,		/* . */
+	getattr:	NULL,		/* . */
+};
+
+#if 0
+struct inode_operations {
+	int (*create) (struct inode *,struct dentry *,int);
+	struct dentry * (*lookup) (struct inode *,struct dentry *);
+	int (*link) (struct dentry *,struct inode *,struct dentry *);
+	int (*unlink) (struct inode *,struct dentry *);
+	int (*symlink) (struct inode *,struct dentry *,const char *);
+	int (*mkdir) (struct inode *,struct dentry *,int);
+	int (*rmdir) (struct inode *,struct dentry *);
+	int (*mknod) (struct inode *,struct dentry *,int,int);
+	int (*rename) (struct inode *, struct dentry *,
+			struct inode *, struct dentry *);
+	int (*readlink) (struct dentry *, char *,int);
+	int (*follow_link) (struct dentry *, struct nameidata *);
+	void (*truncate) (struct inode *);
+	int (*permission) (struct inode *, int);
+	int (*revalidate) (struct dentry *);
+	int (*setattr) (struct dentry *, struct iattr *);
+	int (*getattr) (struct dentry *, struct iattr *);
+};
+#endif
+

fs/ntfs/ntfs.h

+/*
+ * ntfs.h - Defines for NTFS Linux kernel driver. Part of the Linux-NTFS
+ *	    project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_H
+#define _LINUX_NTFS_H
+
+#include <linux/version.h>
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,5)
+#	error The NTFS driver requires at least kernel 2.5.5.
+#endif
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/compiler.h>
+#include <linux/fs.h>
+#include <linux/nls.h>
+#include <linux/pagemap.h>
+#include <linux/smp.h>
+#include <asm/atomic.h>
+
+#include "types.h"
+#include "debug.h"
+#include "malloc.h"
+#include "endian.h"
+#include "volume.h"
+#include "inode.h"
+#include "layout.h"
+#include "attrib.h"
+#include "mft.h"
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
+typedef long sector_t;
+#endif
+
+typedef enum {
+	NTFS_BLOCK_SIZE		= 512,
+	NTFS_BLOCK_SIZE_BITS	= 9,
+	NTFS_SB_MAGIC		= 0x5346544e,	/* 'NTFS' */
+	NTFS_MAX_NAME_LEN	= 255,
+} NTFS_CONSTANTS;
+
+/*
+ * Defined bits for the state field in the ntfs_inode structure.
+ * (f) = files only, (d) = directories only
+ */
+typedef enum {
+	NI_Dirty,		/* 1: Mft record needs to be written to disk. */
+	NI_AttrList,		/* 1: Mft record contains an attribute list. */
+	NI_AttrListNonResident,	/* 1: Attribute list is non-resident. Implies
+				      NI_AttrList is set. */
+	NI_NonResident,		/* 1: Unnamed data attr is non-resident (f).
+				   1: $I30 index alloc attr is present (d). */
+	NI_Compressed,		/* 1: Unnamed data attr is compressed (f).
+				   1: Create compressed files by default (d). */
+	NI_Encrypted,		/* 1: Unnamed data attr is encrypted (f).
+				   1: Create encrypted files by default (d). */
+	NI_BmpNonResident,	/* 1: $I30 bitmap attr is non resident (d). */
+} ntfs_inode_state_bits;
+
+/*
+ * NOTE: We should be adding dirty mft records to a list somewhere and they
+ * should be independent of the (ntfs/vfs) inode structure so that an inode can
+ * be removed but the record can be left dirty for syncing later.
+ */
+
+#define NInoDirty(n_ino)	  test_bit(NI_Dirty, &(n_ino)->state)
+#define NInoSetDirty(n_ino)	  set_bit(NI_Dirty, &(n_ino)->state)
+#define NInoClearDirty(n_ino)	  clear_bit(NI_Dirty, &(n_ino)->state)
+
+#define NInoAttrList(n_ino)	  test_bit(NI_AttrList, &(n_ino)->state)
+#define NInoNonResident(n_ino)	  test_bit(NI_NonResident, &(n_ino)->state)
+#define NInoIndexAllocPresent(n_ino) test_bit(NI_NonResident, &(n_ino)->state)
+#define NInoCompressed(n_ino)	  test_bit(NI_Compressed, &(n_ino)->state)
+#define NInoEncrypted(n_ino)	  test_bit(NI_Encrypted, &(n_ino)->state)
+#define NInoBmpNonResident(n_ino) test_bit(NI_BmpNonResident, &(n_ino)->state)
+
+/* Global variables. */
+
+/* Slab caches (from super.c). */
+extern kmem_cache_t *ntfs_name_cache;
+extern kmem_cache_t *ntfs_inode_cache;
+extern kmem_cache_t *ntfs_big_inode_cache;
+extern kmem_cache_t *ntfs_attr_ctx_cache;
+
+/* The little endian Unicode string $I30 as a global constant. */
+extern const uchar_t I30[5];
+
+/* The various operations structs defined throughout the driver files. */
+extern struct super_operations ntfs_mount_sops;
+extern struct super_operations ntfs_sops;
+extern struct file_operations ntfs_file_ops;
+extern struct inode_operations ntfs_file_inode_ops;
+extern struct address_space_operations ntfs_file_aops;
+extern struct file_operations ntfs_dir_ops;
+extern struct inode_operations ntfs_dir_inode_ops;
+extern struct address_space_operations ntfs_dir_aops;
+extern struct file_operations ntfs_empty_file_ops;
+extern struct inode_operations ntfs_empty_inode_ops;
+extern struct address_space_operations ntfs_mft_aops;
+extern struct address_space_operations ntfs_mftbmp_aops;
+
+/* Generic macro to convert pointers to values for comparison purposes. */
+#ifndef p2n
+#define p2n(p)          ((ptrdiff_t)((ptrdiff_t*)(p)))
+#endif
+
+/**
+ * NTFS_SB - return the ntfs volume given a vfs super block
+ * @sb:		VFS super block
+ *
+ * NTFS_SB() returns the ntfs volume associated with the VFS super block @sb.
+ */
+static inline ntfs_volume *NTFS_SB(struct super_block *sb)
+{
+	return sb->u.generic_sbp;
+}
+
+/**
+ * ntfs_unmap_page - release a page that was mapped using ntfs_map_page()
+ * @page:	the page to release
+ *
+ * Unpin, unmap and release a page that was obtained from ntfs_map_page().
+ */
+static inline void ntfs_unmap_page(struct page *page)
+{
+	kunmap(page);
+	page_cache_release(page);
+}
+
+/**
+ * ntfs_map_page - map a page into accessible memory, reading it if necessary
+ * @mapping:	address space for which to obtain the page
+ * @index:	index into the page cache for @mapping of the page to map
+ *
+ * Read a page from the page cache of the address space @mapping at position
+ * @index, where @index is in units of PAGE_CACHE_SIZE, and not in bytes.
+ *
+ * If the page is not in memory it is loaded from disk first using the readpage
+ * method defined in the address space operations of @mapping and the page is
+ * added to the page cache of @mapping in the process.
+ *
+ * If the page is in high memory it is mapped into memory directly addressible
+ * by the kernel.
+ *
+ * Finally the page count is incremented, thus pinning the page into place.
+ *
+ * The above means that page_address(page) can be used on all pages obtained
+ * with ntfs_map_page() to get the kernel virtual address of the page.
+ *
+ * When finished with the page, the caller has to call ntfs_unmap_page() to
+ * unpin, unmap and release the page.
+ *
+ * Note this does not grant exclusive access. If such is desired, the caller
+ * must provide it independently of the ntfs_{un}map_page() calls by using
+ * a {rw_}semaphore or other means of serialization. A spin lock cannot be
+ * used as ntfs_map_page() can block.
+ *
+ * The unlocked and uptodate page is returned on success or an encoded error
+ * on failure. Caller has to test for error using the IS_ERR() macro on the
+ * return value. If that evaluates to TRUE, the negative error code can be
+ * obtained using PTR_ERR() on the return value of ntfs_map_page().
+ */
+static inline struct page *ntfs_map_page(struct address_space *mapping,
+		unsigned long index)
+{
+	struct page *page = read_cache_page(mapping, index,
+			(filler_t*)mapping->a_ops->readpage, NULL);
+
+	if (!IS_ERR(page)) {
+		wait_on_page(page);
+		kmap(page);
+		if (Page_Uptodate(page) && !PageError(page))
+			return page;
+		ntfs_unmap_page(page);
+		return ERR_PTR(-EIO);
+	}
+	return page;
+}
+
+/* Declarations of functions and global variables. */
+
+/* From fs/ntfs/aops.c */
+extern int ntfs_file_get_block(struct inode *vi, const sector_t blk,
+		struct buffer_head *bh, const int create);
+extern void end_buffer_read_index_async(struct buffer_head *bh, int uptodate);
+
+/* From fs/ntfs/compress.c */
+extern int ntfs_file_read_compressed_block(struct page *page);
+
+/* From fs/ntfs/super.c */
+#define default_upcase_len 0x10000
+extern wchar_t *default_upcase;
+extern unsigned long ntfs_nr_upcase_users;
+extern unsigned long ntfs_nr_mounts;
+extern struct semaphore ntfs_lock;
+
+typedef struct {
+	int val;
+	char *str;
+} option_t;
+extern const option_t on_errors_arr[];
+
+/* From fs/ntfs/compress.c */
+extern int allocate_compression_buffers(void);
+extern void free_compression_buffers(void);
+
+/* From fs/ntfs/mst.c */
+extern inline void __post_read_mst_fixup(NTFS_RECORD *b, const u32 size);
+extern int post_read_mst_fixup(NTFS_RECORD *b, const u32 size);
+extern int pre_write_mst_fixup(NTFS_RECORD *b, const u32 size);
+
+/* From fs/ntfs/time.c */
+extern inline s64 utc2ntfs(const time_t time);
+extern inline s64 get_current_ntfs_time(void);
+extern inline time_t ntfs2utc(const s64 time);
+
+/* From fs/ntfs/dir.c */
+extern u64 ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const uchar_t *uname,
+		const int uname_len);
+
+/* From fs/ntfs/unistr.c */
+extern BOOL ntfs_are_names_equal(const uchar_t *s1, size_t s1_len,
+		const uchar_t *s2, size_t s2_len,
+		const IGNORE_CASE_BOOL ic,
+		const uchar_t *upcase, const u32 upcase_size);
+extern int ntfs_collate_names(const uchar_t *name1, const u32 name1_len,
+		const uchar_t *name2, const u32 name2_len,
+		const int err_val, const IGNORE_CASE_BOOL ic,
+		const uchar_t *upcase, const u32 upcase_len);
+extern int ntfs_ucsncmp(const uchar_t *s1, const uchar_t *s2, size_t n);
+extern int ntfs_ucsncasecmp(const uchar_t *s1, const uchar_t *s2, size_t n,
+		const uchar_t *upcase, const u32 upcase_size);
+extern void ntfs_upcase_name(uchar_t *name, u32 name_len,
+		const uchar_t *upcase, const u32 upcase_len);
+extern void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr,
+		const uchar_t *upcase, const u32 upcase_len);
+extern int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1,
+		FILE_NAME_ATTR *file_name_attr2,
+		const int err_val, const IGNORE_CASE_BOOL ic,
+		const uchar_t *upcase, const u32 upcase_len);
+extern int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins,
+		const int ins_len, uchar_t **outs);
+extern int ntfs_ucstonls(const ntfs_volume *vol, const uchar_t *ins,
+		const int ins_len, unsigned char **outs, int outs_len);
+
+/* From fs/ntfs/upcase.c */
+extern uchar_t *generate_default_upcase(void);
+
+#endif /* _LINUX_NTFS_H */
+

fs/ntfs/ntfsendian.h

-/*
- * ntfsendian.h
- *
- * Copyright (C) 1998, 1999 Martin von Lwis
- * Copyright (C) 1998 Joseph Malicki
- * Copyright (C) 1999 Werner Seiler
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
- */
-#include <asm/byteorder.h>
-
-#define CPU_TO_LE16(a) __cpu_to_le16(a)
-#define CPU_TO_LE32(a) __cpu_to_le32(a)
-#define CPU_TO_LE64(a) __cpu_to_le64(a)
-
-#define LE16_TO_CPU(a) __cpu_to_le16(a)
-#define LE32_TO_CPU(a) __cpu_to_le32(a)
-#define LE64_TO_CPU(a) __cpu_to_le64(a)
-
-#define NTFS_GETU8(p)      (*(ntfs_u8*)(p))
-#define NTFS_GETU16(p)     ((ntfs_u16)LE16_TO_CPU(*(ntfs_u16*)(p)))
-#define NTFS_GETU24(p)     ((ntfs_u32)NTFS_GETU16(p) | \
-			   ((ntfs_u32)NTFS_GETU8(((char*)(p)) + 2) << 16))
-#define NTFS_GETU32(p)     ((ntfs_u32)LE32_TO_CPU(*(ntfs_u32*)(p)))
-#define NTFS_GETU40(p)     ((ntfs_u64)NTFS_GETU32(p) | \
-			   (((ntfs_u64)NTFS_GETU8(((char*)(p)) + 4)) << 32))
-#define NTFS_GETU48(p)     ((ntfs_u64)NTFS_GETU32(p) | \
-			   (((ntfs_u64)NTFS_GETU16(((char*)(p)) + 4)) << 32))
-#define NTFS_GETU56(p)     ((ntfs_u64)NTFS_GETU32(p) | \
-			   (((ntfs_u64)NTFS_GETU24(((char*)(p)) + 4)) << 32))
-#define NTFS_GETU64(p)     ((ntfs_u64)LE64_TO_CPU(*(ntfs_u64*)(p)))
- 
- /* Macros writing unsigned integers */
-#define NTFS_PUTU8(p,v)      ((*(ntfs_u8*)(p)) = (v))
-#define NTFS_PUTU16(p,v)     ((*(ntfs_u16*)(p)) = CPU_TO_LE16(v))
-#define NTFS_PUTU24(p,v)     NTFS_PUTU16(p, (v) & 0xFFFF);\
-                             NTFS_PUTU8(((char*)(p)) + 2, (v) >> 16)
-#define NTFS_PUTU32(p,v)     ((*(ntfs_u32*)(p)) = CPU_TO_LE32(v))
-#define NTFS_PUTU64(p,v)     ((*(ntfs_u64*)(p)) = CPU_TO_LE64(v))
- 
- /* Macros reading signed integers */
-#define NTFS_GETS8(p)        ((*(ntfs_s8*)(p)))
-#define NTFS_GETS16(p)       ((ntfs_s16)LE16_TO_CPU(*(short*)(p)))
-#define NTFS_GETS24(p)       (NTFS_GETU24(p) < 0x800000 ? \
-					(int)NTFS_GETU24(p) : \
-					(int)(NTFS_GETU24(p) - 0x1000000))
-#define NTFS_GETS32(p)       ((ntfs_s32)LE32_TO_CPU(*(int*)(p)))
-#define NTFS_GETS40(p)       (((ntfs_s64)NTFS_GETU32(p)) | \
-			     (((ntfs_s64)NTFS_GETS8(((char*)(p)) + 4)) << 32))
-#define NTFS_GETS48(p)       (((ntfs_s64)NTFS_GETU32(p)) | \
-			     (((ntfs_s64)NTFS_GETS16(((char*)(p)) + 4)) << 32))
-#define NTFS_GETS56(p)       (((ntfs_s64)NTFS_GETU32(p)) | \
-			     (((ntfs_s64)NTFS_GETS24(((char*)(p)) + 4)) << 32))
-#define NTFS_GETS64(p)	     ((ntfs_s64)NTFS_GETU64(p))
- 
-#define NTFS_PUTS8(p,v)      NTFS_PUTU8(p,v)
-#define NTFS_PUTS16(p,v)     NTFS_PUTU16(p,v)
-#define NTFS_PUTS24(p,v)     NTFS_PUTU24(p,v)
-#define NTFS_PUTS32(p,v)     NTFS_PUTU32(p,v)
-#define NTFS_PUTS64(p,v)     NTFS_PUTU64(p,v)
-

fs/ntfs/ntfstypes.h

-/*
- * ntfstypes.h - This file defines four things:
- * - Generic platform independent fixed-size types (e.g. ntfs_u32).
- * - Specific fixed-size types (e.g. ntfs_offset_t).
- * - Macros that read and write those types from and to byte arrays.
- * - Types derived from OS specific ones.
- *
- * Copyright (C) 1996, 1998, 1999 Martin von Lwis
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
- */
-#include <linux/fs.h>
-#include "ntfsendian.h"
-#include <asm/types.h>
-
-/* Integral types */
-#ifndef NTFS_INTEGRAL_TYPES
-#define NTFS_INTEGRAL_TYPES
-typedef u8  ntfs_u8;
-typedef u16 ntfs_u16;
-typedef u32 ntfs_u32;
-typedef u64 ntfs_u64;
-typedef s8  ntfs_s8;
-typedef s16 ntfs_s16;
-typedef s32 ntfs_s32;
-typedef s64 ntfs_s64;
-#endif
-
-/* Unicode character type */
-#ifndef NTFS_WCHAR_T
-#define NTFS_WCHAR_T
-typedef u16 ntfs_wchar_t;
-#endif
-/* File offset */
-#ifndef NTFS_OFFSET_T
-#define NTFS_OFFSET_T
-typedef s64 ntfs_offset_t;
-#endif
-/* UTC */
-#ifndef NTFS_TIME64_T
-#define NTFS_TIME64_T
-typedef u64 ntfs_time64_t;
-#endif
-/*
- * This is really signed long long. So we support only volumes up to 2Tb. This
- * is ok as Win2k also only uses 32-bits to store clusters.
- * Whatever you do keep this a SIGNED value or a lot of NTFS users with
- * corrupted filesystems will lynch you! It causes massive fs corruption when
- * unsigned due to the nature of many checks relying on being performed on
- * signed quantities. (AIA)
- */
-#ifndef NTFS_CLUSTER_T
-#define NTFS_CLUSTER_T
-typedef s32 ntfs_cluster_t;
-#endif
-
-/* Architecture independent macros. */
-
-/* PUTU32 would not clear all bytes. */
-#define NTFS_PUTINUM(p,i)    NTFS_PUTU64(p, i->i_number); \
-                             NTFS_PUTU16(((char*)p) + 6, i->sequence_number)
-
-/* System dependent types. */
-#include <asm/posix_types.h>
-#ifndef NTMODE_T
-#define NTMODE_T
-typedef __kernel_mode_t ntmode_t;
-#endif
-#ifndef NTFS_UID_T
-#define NTFS_UID_T
-typedef uid_t ntfs_uid_t;
-#endif
-#ifndef NTFS_GID_T
-#define NTFS_GID_T
-typedef gid_t ntfs_gid_t;
-#endif
-#ifndef NTFS_SIZE_T
-#define NTFS_SIZE_T
-typedef __kernel_size_t ntfs_size_t;
-#endif
-#ifndef NTFS_TIME_T
-#define NTFS_TIME_T
-typedef __kernel_time_t ntfs_time_t;
-#endif
-

fs/ntfs/struct.h

-/*
- * struct.h - Structure definitions
- *
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (C) 2000-2001 Anton Altaparmakov (AIA)
- */
-#include <linux/ntfs_fs.h>
-
-/* Necessary forward definition. */
-struct ntfs_inode;
-
-/* Which files should be returned from a director listing. */
-#define ngt_dos   1	/* only short names, no system files */
-#define ngt_nt    2	/* only long names, all-uppercase becomes 
-			 * all-lowercase, no system files */
-#define ngt_posix 3	/* all names except system files */
-#define ngt_full  4	/* all entries */
-
-typedef struct ntfs_sb_info ntfs_volume;
-
-typedef struct {
-	ntfs_cluster_t lcn;
-	ntfs_cluster_t len;
-} ntfs_runlist;
-
-typedef struct ntfs_attribute {
-	int type;
-	ntfs_u16 *name;
-	int namelen;
-	int attrno;
-	__s64 size, allocated, initialized, compsize;
-	ATTR_FLAGS flags;
-	__u8 resident, indexed;
-	int cengine;
-	union {
-		void *data;             /* if resident */
-		struct {
-			ntfs_runlist *runlist;
-			unsigned long len;
-		} r;
-	} d;
-} ntfs_attribute;
-
-typedef struct ntfs_inode_info ntfs_inode;
-
-/* Structure to define IO to user buffer. do_read means that the destination
- * has to be written using fn_put, do_write means that the destination has to
- * read using fn_get. So, do_read is from a user's point of view, while put and
- * get are from the driver's point of view. The first argument is always the
- * destination of the IO. */
-typedef struct ntfs_io{
-	int do_read;
-	void (*fn_put)(struct ntfs_io *dest, void *buf, ntfs_size_t);
-	void (*fn_get)(void *buf, struct ntfs_io *src, ntfs_size_t len);
-	void *param;
-	unsigned long size;
-} ntfs_io;
-
-#if 0
-typedef struct {
-	ntfs_volume *vol;
-	ntfs_inode *ino;
-	int type;
-	char *name;
-	int mftno;
-	int start_vcn;
-} ntfs_attrlist_item;
-#endif
-

fs/ntfs/super.h

-/*
- * super.h - Header file for super.c
- *
- * Copyright (C) 1995-1997 Martin von Lwis
- * Copyright (C) 1996-1997 Rgis Duchesne
- * Copyright (c) 2001 Anton Altaparmakov
- */
-
-int ntfs_get_free_cluster_count(ntfs_inode *bitmap);
-
-int ntfs_get_volumesize(ntfs_volume *vol, __s64 *vol_size);
-
-int ntfs_init_volume(ntfs_volume *vol, char *boot);
-
-int ntfs_load_special_files(ntfs_volume *vol);
-
-int ntfs_release_volume(ntfs_volume *vol);
-
-int ntfs_insert_fixups(unsigned char *rec, int rec_size);
-
-int ntfs_fixup_record(char *record, char *magic, int size);
-
-int ntfs_allocate_clusters(ntfs_volume *vol, ntfs_cluster_t *location,
-		ntfs_cluster_t *count, ntfs_runlist **rl, int *rl_len,
-		const NTFS_CLUSTER_ALLOCATION_ZONES zone);
-
-int ntfs_deallocate_cluster_run(const ntfs_volume *vol,
-		const ntfs_cluster_t lcn, const ntfs_cluster_t len);
-
-int ntfs_deallocate_clusters(const ntfs_volume *vol, const ntfs_runlist *rl,
-		const int rl_len);
-

fs/ntfs/support.c

-/*
- * support.c -  Specific support functions
- *
- * Copyright (C) 1997 Martin von Lwis
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
- */
-
-#include "ntfstypes.h"
-#include "struct.h"
-#include "support.h"
-
-#include <stdarg.h>
-#include <linux/slab.h>
-#include <linux/locks.h>
-#include <linux/fs.h>
-#include "util.h"
-#include "inode.h"
-#include "macros.h"
-#include <linux/nls.h>
-
-static char print_buf[1024];
-
-#ifdef DEBUG
-#include "sysctl.h"
-#include <linux/kernel.h>
-
-/* Debugging output */
-void ntfs_debug(int mask, const char *fmt, ...)
-{
-	va_list ap;
-
-	/* Filter it with the debugging level required */
-	if (ntdebug & mask) {
-		va_start(ap,fmt);
-		strcpy(print_buf, KERN_DEBUG "NTFS: ");
-		vsprintf(print_buf + 9, fmt, ap);
-		printk(print_buf);
-		va_end(ap);
-	}
-}
-
-#ifndef ntfs_malloc
-/* Verbose kmalloc */
-void *ntfs_malloc(int size)
-{
-	void *ret;
-
-	ret = kmalloc(size, GFP_KERNEL);
-	ntfs_debug(DEBUG_MALLOC, "Allocating %x at %p\n", size, ret);
-
-	return ret;
-}
-#endif
-
-#ifndef ntfs_free
-/* Verbose kfree() */
-void ntfs_free(void *block)
-{
-        ntfs_debug(DEBUG_MALLOC, "Freeing memory at %p\n", block);
-	kfree(block);
-}
-#endif
-#else /* End of DEBUG functions. Normal ones below... */
-
-#ifndef ntfs_malloc
-void *ntfs_malloc(int size)
-{
-	return kmalloc(size, GFP_KERNEL);
-}
-#endif
-
-#ifndef ntfs_free
-void ntfs_free(void *block)
-{
-	kfree(block);
-}
-#endif
-#endif /* DEBUG */
-
-void ntfs_bzero(void *s, int n)
-{
-	memset(s, 0, n);
-}
-
-/* These functions deliberately return no value. It is dest, anyway,
-   and not used anywhere in the NTFS code.  */
-
-void ntfs_memcpy(void *dest, const void *src, ntfs_size_t n)
-{
-	memcpy(dest, src, n);
-}
-
-void ntfs_memmove(void *dest, const void *src, ntfs_size_t n)
-{
-	memmove(dest, src, n);
-}
-
-/* Warn that an error occurred. */
-void ntfs_error(const char *fmt,...)
-{
-        va_list ap;
-
-        va_start(ap, fmt);
-        strcpy(print_buf, KERN_ERR "NTFS: ");
-        vsprintf(print_buf + 9, fmt, ap);
-        printk(print_buf);
-        va_end(ap);
-}
-
-int ntfs_read_mft_record(ntfs_volume *vol, int mftno, char *buf)
-{
-	int error;
-	ntfs_io io;
-
-	ntfs_debug(DEBUG_OTHER, "read_mft_record 0x%x\n", mftno);
-	if (mftno == FILE_Mft)
-	{
-		ntfs_memcpy(buf, vol->mft, vol->mft_record_size);
-		return 0;
-	}
-	if (!vol->mft_ino)
-	{
-		printk(KERN_ERR "NTFS: mft_ino is NULL. Something is terribly "
-				"wrong here!\n");
-		return -ENODATA;
-	}
- 	io.fn_put = ntfs_put;
-	io.fn_get = 0;
-	io.param = buf;
-	io.size = vol->mft_record_size;
-	ntfs_debug(DEBUG_OTHER, "read_mft_record: calling ntfs_read_attr with: "
-		"mftno = 0x%x, vol->mft_record_size_bits = 0x%x, "
-		"mftno << vol->mft_record_size_bits = 0x%Lx\n", mftno,
-		vol->mft_record_size_bits,
-		(__s64)mftno << vol->mft_record_size_bits);
-	error = ntfs_read_attr(vol->mft_ino, vol->at_data, NULL,
-				(__s64)mftno << vol->mft_record_size_bits, &io);
-	if (error || (io.size != vol->mft_record_size)) {
-		ntfs_debug(DEBUG_OTHER, "read_mft_record: read 0x%x failed "
-				   	"(%d,%d,%d)\n", mftno, error, io.size,
-				   	vol->mft_record_size);
-		return error ? error : -ENODATA;
-	}
-	ntfs_debug(DEBUG_OTHER, "read_mft_record: finished read 0x%x\n", mftno);
-	if (!ntfs_check_mft_record(vol, buf)) {
-		/* FIXME: This is incomplete behaviour. We might be able to
-		 * recover at this stage. ntfs_check_mft_record() is too
-		 * conservative at aborting it's operations. It is OK for
-		 * now as we just can't handle some on disk structures
-		 * this way. (AIA) */
-		printk(KERN_WARNING "NTFS: Invalid MFT record for 0x%x\n", mftno);
-		return -EIO;
-	}
-	ntfs_debug(DEBUG_OTHER, "read_mft_record: Done 0x%x\n", mftno);
-	return 0;
-}
-
-int ntfs_getput_clusters(ntfs_volume *vol, int cluster, ntfs_size_t start_offs,
-		ntfs_io *buf)
-{
-	struct super_block *sb = NTFS_SB(vol);
-	struct buffer_head *bh;
-	int length = buf->size;
-	int error = 0;
-	ntfs_size_t to_copy;
-
-	ntfs_debug(DEBUG_OTHER, "%s_clusters %d %d %d\n", 
-		   buf->do_read ? "get" : "put", cluster, start_offs, length);
-	to_copy = vol->cluster_size - start_offs;
-	while (length) {
-		if (!(bh = sb_bread(sb, cluster))) {
-			ntfs_debug(DEBUG_OTHER, "%s failed\n",
-				   buf->do_read ? "Reading" : "Writing");
-			error = -EIO;
-			goto error_ret;
-		}
-		if (to_copy > length)
-			to_copy = length;
-		lock_buffer(bh);
-		if (buf->do_read) {
-			buf->fn_put(buf, bh->b_data + start_offs, to_copy);
-			unlock_buffer(bh);
-		} else {
-			buf->fn_get(bh->b_data + start_offs, buf, to_copy);
-			mark_buffer_dirty(bh);
-			unlock_buffer(bh);
-			/*
-			 * Note: We treat synchronous IO on a per volume basis
-			 * disregarding flags of individual inodes. This can
-			 * lead to some strange write ordering effects upon a
-			 * remount with a change in the sync flag but it should
-			 * not break anything. [Except if the system crashes
-			 * at that point in time but there would be more thigs
-			 * to worry about than that in that case...]. (AIA)
-			 */
-			if (sb->s_flags & MS_SYNCHRONOUS) {
-				ll_rw_block(WRITE, 1, &bh);
-				wait_on_buffer(bh);
-				if (buffer_req(bh) && !buffer_uptodate(bh)) {
-					printk(KERN_ERR "IO error syncing NTFS "
-					       "cluster [%s:%i]\n",
-					       sb->s_id, cluster);
-					brelse(bh);
-					error = -EIO;
-					goto error_ret;
-				}
-			}
-		}
-		brelse(bh);
-		length -= to_copy;
-		start_offs = 0;
-		to_copy = vol->cluster_size;
-		cluster++;
-	}
-error_ret:
-	return error;
-}
-
-ntfs_time64_t ntfs_now(void)
-{
-	return ntfs_unixutc2ntutc(CURRENT_TIME);
-}
-
-int ntfs_dupuni2map(ntfs_volume *vol, ntfs_u16 *in, int in_len, char **out,
-		int *out_len)
-{
-	int i, o, chl, chi;
-	char *result, *buf, charbuf[NLS_MAX_CHARSET_SIZE];
-	struct nls_table *nls = vol->nls_map;
-
-	result = ntfs_malloc(in_len + 1);
-	if (!result)
-		return -ENOMEM;
-	*out_len = in_len;
-	for (i = o = 0; i < in_len; i++) {
-		/* FIXME: Byte order? */
-		wchar_t uni = in[i];
-		if ((chl = nls->uni2char(uni, charbuf,
-				NLS_MAX_CHARSET_SIZE)) > 0) {
-			/* Adjust result buffer. */
-			if (chl > 1) {
-				buf = ntfs_malloc(*out_len + chl - 1);
-				if (!buf) {
-					i = -ENOMEM;
-					goto err_ret;
-				}
-				memcpy(buf, result, o);
-				ntfs_free(result);
-				result = buf;
-				*out_len += (chl - 1);
-			}
-			for (chi = 0; chi < chl; chi++)
-				result[o++] = charbuf[chi];
-		} else {
-			/* Invalid character. */
-			printk(KERN_ERR "NTFS: Unicode name contains a "
-					"character that cannot be converted "
-					"to chosen character set. Remount "
-					"with utf8 encoding and this should "
-					"work.\n");
-			i = -EILSEQ;
-			goto err_ret;
-		}
-	}
-	result[*out_len] = '\0';
-	*out = result;
-	return 0;
-err_ret:
-	ntfs_free(result);
-	*out_len = 0;
-	*out = NULL;
-	return i;
-}
-
-int ntfs_dupmap2uni(ntfs_volume *vol, char* in, int in_len, ntfs_u16 **out,
-		int *out_len)
-{
-	int i, o;
-	ntfs_u16 *result;
-	struct nls_table *nls = vol->nls_map;
-
-	*out = result = ntfs_malloc(2 * in_len);
-	if (!result) {
-		*out_len = 0;
-		return -ENOMEM;
-	}
-	*out_len = in_len;
-	for (i = o = 0; i < in_len; i++, o++) {
-		wchar_t uni;
-		int charlen;
-
-		charlen = nls->char2uni(&in[i], in_len - i, &uni);
-		if (charlen < 0) {
-			i = charlen;
-			goto err_ret;
-		}
-		*out_len -= charlen - 1;
-		i += charlen - 1;
-		/* FIXME: Byte order? */
-		result[o] = uni;
-		if (!result[o]) {
-			i = -EILSEQ;
-			goto err_ret;
-		}
-	}
-	return 0;
-err_ret:
-	printk(KERN_ERR "NTFS: Name contains a character that cannot be "
-			"converted to Unicode.\n");
-	ntfs_free(result);
-	*out_len = 0;
-	*out = NULL;
-	return i;
-}
-

fs/ntfs/support.h

-/*
- * support.h - Header file for specific support.c
- *
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (c) 2001 Anton Altaparmakov (AIA)
- */
-
-/* Debug levels */
-#define DEBUG_OTHER	1
-#define DEBUG_MALLOC	2
-#define DEBUG_BSD       4
-#define DEBUG_LINUX     8
-#define DEBUG_DIR1     16
-#define DEBUG_DIR2     32
-#define DEBUG_DIR3     64
-#define DEBUG_FILE1   128
-#define DEBUG_FILE2   256
-#define DEBUG_FILE3   512
-#define DEBUG_NAME1  1024
-#define DEBUG_NAME2  2048
-
-#ifdef DEBUG
-void ntfs_debug(int mask, const char *fmt, ...);
-#else
-#define ntfs_debug(mask, fmt...)	do {} while (0)
-#endif
-
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-
-#define ntfs_malloc(size)  kmalloc(size, GFP_KERNEL)
-
-#define ntfs_free(ptr)     kfree(ptr)
-
-#define ntfs_vmalloc(size)	vmalloc_32(size)
-
-#define ntfs_vfree(ptr)		vfree(ptr)
-
-void ntfs_bzero(void *s, int n);
-
-void ntfs_memcpy(void *dest, const void *src, ntfs_size_t n);
-
-void ntfs_memmove(void *dest, const void *src, ntfs_size_t n);
-
-void ntfs_error(const char *fmt,...);
-
-int ntfs_read_mft_record(ntfs_volume *vol, int mftno, char *buf);
-
-int ntfs_getput_clusters(ntfs_volume *pvol, int cluster, ntfs_size_t offs,
-			 ntfs_io *buf);
-
-ntfs_time64_t ntfs_now(void);
-
-int ntfs_dupuni2map(ntfs_volume *vol, ntfs_u16 *in, int in_len, char **out,
-		    int *out_len);
-
-int ntfs_dupmap2uni(ntfs_volume *vol, char* in, int in_len, ntfs_u16 **out,
-		    int *out_len);
-

fs/ntfs/sysctl.c

 /*
- * sysctl.c - System control stuff
+ * sysctl.c - Code for sysctl handling in NTFS Linux kernel driver. Part of
+ *	      the Linux-NTFS project. Adapted from the old NTFS driver,
+ *	      Copyright (C) 1997 Martin von Lwis, Rgis Duchesne.
  *
- * Copyright (C) 1997 Martin von Lwis
- * Copyright (C) 1997 Rgis Duchesne
+ * Copyright (c) 2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#include "sysctl.h"
-
 #ifdef DEBUG
-#include <linux/locks.h>
+
+#include <linux/module.h>
+
+#ifdef CONFIG_SYSCTL
+
+#include <linux/proc_fs.h>
 #include <linux/sysctl.h>
 
-int ntdebug = 0;
+#include "sysctl.h"
+#include "debug.h"
+
+#define FS_NTFS	1
+
+/* Definition of the ntfs sysctl. */
+static ctl_table ntfs_sysctls[] = {
+	{ FS_NTFS, "ntfs-debug", 		/* Binary and text IDs. */
+	  &debug_msgs,sizeof(debug_msgs),	/* Data pointer and size. */
+	  0644,	NULL, &proc_dointvec },		/* Mode, child, proc handler. */
+	{ 0 }
+};
+
+/* Define the parent directory /proc/sys/fs. */
+static ctl_table sysctls_root[] = {
+	{ CTL_FS, "fs", NULL, 0, 0555, ntfs_sysctls },
+	{ 0 }
+};
+
+/* Storage for the sysctls header. */
+static struct ctl_table_header *sysctls_root_table = NULL;
 
-/* Add or remove the debug sysctl
- * Is this really the only file system with sysctls ?
+/**
+ * ntfs_sysctl - add or remove the debug sysctl
+ * @add:	add (1) or remove (0) the sysctl
+ *
+ * Add or remove the debug sysctl. Return 0 on success or -errno on error.
  */
-void ntfs_sysctl(int add)
+int ntfs_sysctl(int add)
 {
-#define FS_NTFS             1
-	/* Definition of the sysctl */
-	static ctl_table ntfs_sysctls[]={
-		{FS_NTFS,                  /* ID */
-		 "ntfs-debug",             /* name in /proc */
-		 &ntdebug,sizeof(ntdebug), /* data ptr, data size */
-		 0644,                     /* mode */
-		 0,                        /* child */
-		 proc_dointvec,            /* proc handler */
-		 0,                        /* strategy */
-		 0,                        /* proc control block */
-		 0,0},                     /* extra */
-		{0}
-	};
-	/* Define the parent file : /proc/sys/fs */
-	static ctl_table sysctls_root[]={
-		{CTL_FS,
-		 "fs",
-		 NULL,0,
-		 0555,
-		 ntfs_sysctls},
-		{0}
-	};
-	static struct ctl_table_header *sysctls_root_header = NULL;
-
-	if(add){
-		if(!sysctls_root_header)
-			sysctls_root_header = register_sysctl_table(sysctls_root, 0);
-	} else if(sysctls_root_header) {
-		unregister_sysctl_table(sysctls_root_header);
-		sysctls_root_header = NULL;
+	if (add) {
+		BUG_ON(sysctls_root_table);
+		sysctls_root_table = register_sysctl_table(sysctls_root, 0);
+		if (!sysctls_root_table)
+			return -ENOMEM;
+#ifdef CONFIG_PROC_FS
+		/*
+		 * If the proc file system is in use and we are a module, need
+		 * to set the owner of our proc entry to our module. In the
+		 * non-modular case, THIS_MODULE is NULL, so this is ok.
+		 */
+		ntfs_sysctls[0].de->owner = THIS_MODULE;
+#endif
+	} else {
+		BUG_ON(!sysctls_root_table);
+		unregister_sysctl_table(sysctls_root_table);
+		sysctls_root_table = NULL;
 	}
+	return 0;
 }
+
+#endif /* CONFIG_SYSCTL */
 #endif /* DEBUG */
 

fs/ntfs/sysctl.h

 /*
- * sysctl.h - Header file for sysctl.c
+ * sysctl.h - Defines for sysctl handling in NTFS Linux kernel driver. Part of
+ *	      the Linux-NTFS project. Adapted from the old NTFS driver,
+ *	      Copyright (C) 1997 Martin von Löwis, Régis Duchesne.
  * 
- * Copyright (C) 1997 Martin von Lwis
- * Copyright (C) 1997 Rgis Duchesne
+ * Copyright (c) 2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#ifdef DEBUG
-	extern int ntdebug;
+#ifndef _LINUX_NTFS_SYSCTL_H
+#define _LINUX_NTFS_SYSCTL_H
+
+#include <linux/config.h>
 
-	void ntfs_sysctl(int add);
+#if (DEBUG && CONFIG_SYSCTL)
+
+extern int ntfs_sysctl(int add);
 
-	#define SYSCTL(x)	ntfs_sysctl(x)
 #else
-	#define SYSCTL(x)
-#endif /* DEBUG */
+
+/* Just return success. */
+static inline int ntfs_sysctl(int add)
+{
+	return 0;
+}
+
+#endif /* DEBUG && CONFIG_SYSCTL */
+#endif /* _LINUX_NTFS_SYSCTL_H */
 

fs/ntfs/time.c

+/*
+ * time.c - NTFS time conversion functions. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/sched.h>	/* For CURRENT_TIME. */
+#include <asm/div64.h>		/* For do_div(). */
+
+#include "ntfs.h"
+
+#define NTFS_TIME_OFFSET ((s64)(369 * 365 + 89) * 24 * 3600 * 10000000)
+
+/**
+ * utc2ntfs - convert Linux time to NTFS time
+ * @time:		Linux time to convert to NTFS
+ *
+ * Convert the Linux time @time to its corresponding NTFS time and return that
+ * in little endian format.
+ *
+ * Linux stores time in a long at present and measures it as the number of
+ * 1-second intervals since 1st January 1970, 00:00:00 UTC.
+ *
+ * NTFS uses Microsoft's standard time format which is stored in a s64 and is
+ * measured as the number of 100 nano-second intervals since 1st January 1601,
+ * 00:00:00 UTC.
+ */
+inline s64 utc2ntfs(const time_t time)
+{
+	/* Convert to 100ns intervals and then add the NTFS time offset. */
+	return cpu_to_sle64((s64)time * 10000000 + NTFS_TIME_OFFSET);
+}
+
+/**
+ * get_current_ntfs_time - get the current time in little endian NTFS format
+ *
+ * Get the current time from the Linux kernel, convert it to its corresponding
+ * NTFS time and return that in little endian format.
+ */
+inline s64 get_current_ntfs_time(void)
+{
+	return utc2ntfs(CURRENT_TIME);
+}
+
+/**
+ * ntfs2utc - convert NTFS time to Linux time
+ * @time:		NTFS time (little endian) to convert to Linux
+ *
+ * Convert the little endian NTFS time @time to its corresponding Linux time
+ * and return that in cpu format.
+ *
+ * Linux stores time in a long at present and measures it as the number of
+ * 1-second intervals since 1st January 1970, 00:00:00 UTC.
+ *
+ * NTFS uses Microsoft's standard time format which is stored in a s64 and is
+ * measured as the number of 100 nano-second intervals since 1st January 1601,
+ * 00:00:00 UTC.
+ */
+inline time_t ntfs2utc(const s64 time)
+{
+	/* Subtract the NTFS time offset, then convert to 1s intervals. */
+	s64 t = sle64_to_cpu(time) - NTFS_TIME_OFFSET;
+	do_div(t, 10000000);
+	return (time_t)t;
+}
+

fs/ntfs/types.h

+/*
+ * types.h - Defines for NTFS Linux kernel driver specific types.
+ *	     Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_TYPES_H
+#define _LINUX_NTFS_TYPES_H
+
+#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
+#define SN(X)   X	/* Struct Name */
+#define SC(P,N) P.N	/* ShortCut: Prefix, Name */
+#else
+#define SN(X)
+#define SC(P,N) N
+#endif
+
+/* 2-byte Unicode character type. */
+typedef u16 uchar_t;
+#define UCHAR_T_SIZE_BITS 1
+
+/*
+ * Clusters are signed 64-bit values on NTFS volumes. We define two types, LCN
+ * and VCN, to allow for type checking and better code readability.
+ */
+typedef s64 VCN;
+typedef s64 LCN;
+
+/**
+ * run_list_element - in memory vcn to lcn mapping array element
+ * @vcn:	starting vcn of the current array element
+ * @lcn:	starting lcn of the current array element
+ * @length:	length in clusters of the current array element
+ * 
+ * The last vcn (in fact the last vcn + 1) is reached when length == 0.
+ * 
+ * When lcn == -1 this means that the count vcns starting at vcn are not 
+ * physically allocated (i.e. this is a hole / data is sparse).
+ */
+typedef struct {	/* In memory vcn to lcn mapping structure element. */
+	VCN vcn;	/* vcn = Starting virtual cluster number. */
+	LCN lcn;	/* lcn = Starting logical cluster number. */
+	s64 length;	/* Run length in clusters. */
+} run_list_element;
+
+/**
+ * run_list - in memory vcn to lcn mapping array including a read/write lock
+ * @rl:		pointer to an array of run list elements
+ * @lock:	read/write spinlock for serializing access to @rl
+ * 
+ */
+typedef struct {
+	run_list_element *rl;
+	rwlock_t lock;
+} run_list;
+
+#define RUN_LIST_INIT		{ NULL, RW_LOCK_UNLOCKED }
+
+#define RUN_LIST(name)		run_list name = RUN_LIST_INIT
+
+#define INIT_RUN_LIST(runlist)	do {					\
+					run_list *___rl = runlist;	\
+					___rl->rl = NULL;		\
+					___rl->lock = RW_LOCK_UNLOCKED; \
+				} while (0)
+
+typedef enum {
+	FALSE = 0,
+	TRUE = 1
+} BOOL;
+
+typedef enum {
+	CASE_SENSITIVE = 0,
+	IGNORE_CASE = 1,
+} IGNORE_CASE_BOOL;
+
+#endif /* _LINUX_NTFS_TYPES_H */
+

fs/ntfs/unistr.c

 /*
- * unistr.c - Unicode string handling. Part of the Linux-NTFS project.
+ * unistr.c - NTFS Unicode string handling. Part of the Linux-NTFS project.
  *
- * Copyright (c) 2000,2001 Anton Altaparmakov.
+ * Copyright (c) 2001 Anton Altaparmakov.
  *
  * This program/include file is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as published
@@ -19,18 +19,21 @@
  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
-#include <linux/string.h>
-#include <linux/fs.h>
-#include <asm/byteorder.h>
+#include "ntfs.h"
 
-#include "unistr.h"
-#include "macros.h"
+/*
+ * IMPORTANT
+ * =========
+ *
+ * All these routines assume that the Unicode characters are in little endian
+ * encoding inside the strings!!!
+ */
 
 /*
  * This is used by the name collation functions to quickly determine what
  * characters are (in)valid.
  */
-const __u8 legal_ansi_char_array[0x40] = {
+static const u8 legal_ansi_char_array[0x40] = {
 	0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
 	0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
 
@@ -58,46 +61,45 @@ const __u8 legal_ansi_char_array[0x40] = {
  * identical, or FALSE (0) if they are not identical. If @ic is IGNORE_CASE,
  * the @upcase table is used to performa a case insensitive comparison.
  */
-int ntfs_are_names_equal(wchar_t *s1, size_t s1_len,
-		     wchar_t *s2, size_t s2_len, int ic,
-		     wchar_t *upcase, __u32 upcase_size)
+BOOL ntfs_are_names_equal(const uchar_t *s1, size_t s1_len,
+		     const uchar_t *s2, size_t s2_len,
+		     const IGNORE_CASE_BOOL ic,
+		     const uchar_t *upcase, const u32 upcase_size)
 {
 	if (s1_len != s2_len)
-		return 0;
-	if (!ic)
-		return memcmp(s1, s2, s1_len << 1) ? 0: 1;
-	return ntfs_wcsncasecmp(s1, s2, s1_len, upcase, upcase_size) ? 0: 1;
+		return FALSE;
+	if (ic == CASE_SENSITIVE)
+		return !ntfs_ucsncmp(s1, s2, s1_len);
+	return !ntfs_ucsncasecmp(s1, s2, s1_len, upcase, upcase_size);
 }
 
 /**
  * ntfs_collate_names - collate two Unicode names
- * @upcase:	upcase table (ignored if @ic is CASE_SENSITIVE)
- * @upcase_len:	upcase table size (ignored if @ic is CASE_SENSITIVE)
  * @name1:	first Unicode name to compare
  * @name2:	second Unicode name to compare
- * @ic:         either CASE_SENSITIVE or IGNORE_CASE
  * @err_val:	if @name1 contains an invalid character return this value
+ * @ic:         either CASE_SENSITIVE or IGNORE_CASE
+ * @upcase:	upcase table (ignored if @ic is CASE_SENSITIVE)
+ * @upcase_len:	upcase table size (ignored if @ic is CASE_SENSITIVE)
  *
  * ntfs_collate_names collates two Unicode names and returns:
  * 
  *  -1 if the first name collates before the second one,
  *   0 if the names match,
  *   1 if the second name collates before the first one, or
- * @ec if an invalid character is encountered in @name1 during the comparison.
+ * @err_val if an invalid character is found in @name1 during the comparison.
  *
  * The following characters are considered invalid: '"', '*', '<', '>' and '?'.
  */
-int ntfs_collate_names(wchar_t *upcase, __u32 upcase_len,
-		       wchar_t *name1, __u32 name1_len,
-		       wchar_t *name2, __u32 name2_len,
-		       int ic, int err_val)
+int ntfs_collate_names(const uchar_t *name1, const u32 name1_len,
+		const uchar_t *name2, const u32 name2_len,
+		const int err_val, const IGNORE_CASE_BOOL ic,
+		const uchar_t *upcase, const u32 upcase_len)
 {
-	__u32 cnt, min_len;
-	wchar_t c1, c2;
+	u32 cnt, min_len;
+	uchar_t c1, c2;
 
-	min_len = name1_len;
-	if (min_len > name2_len)
-		min_len = name2_len;
+	min_len = min(name1_len, name2_len);
 	for (cnt = 0; cnt < min_len; ++cnt) {
 		c1 = le16_to_cpu(*name1++);
 		c2 = le16_to_cpu(*name2++);
@@ -113,8 +115,6 @@ int ntfs_collate_names(wchar_t *upcase, __u32 upcase_len,
 			return -1;
 		if (c1 > c2)
 			return 1;
-		++name1;
-		++name2;
 	}
 	if (name1_len < name2_len)
 		return -1;
@@ -128,7 +128,39 @@ int ntfs_collate_names(wchar_t *upcase, __u32 upcase_len,
 }
 
 /**
- * ntfs_wcsncasecmp - compare two little endian Unicode strings, ignoring case
+ * ntfs_ucsncmp - compare two little endian Unicode strings
+ * @s1:		first string
+ * @s2:		second string
+ * @n:		maximum unicode characters to compare
+ *
+ * Compare the first @n characters of the Unicode strings @s1 and @s2,
+ * The strings in little endian format and appropriate le16_to_cpu()
+ * conversion is performed on non-little endian machines.
+ * 
+ * The function returns an integer less than, equal to, or greater than zero
+ * if @s1 (or the first @n Unicode characters thereof) is found, respectively,
+ * to be less than, to match, or be greater than @s2.
+ */
+int ntfs_ucsncmp(const uchar_t *s1, const uchar_t *s2, size_t n)
+{
+	uchar_t c1, c2;
+	size_t i;
+
+	for (i = 0; i < n; ++i) {
+		c1 = le16_to_cpu(s1[i]);
+		c2 = le16_to_cpu(s2[i]);
+		if (c1 < c2)
+			return -1;
+		if (c1 > c2)
+			return 1;
+		if (!c1)
+			break;
+	}
+	return 0;
+}
+
+/**
+ * ntfs_ucsncasecmp - compare two little endian Unicode strings, ignoring case
  * @s1:			first string
  * @s2:			second string
  * @n:			maximum unicode characters to compare
@@ -145,10 +177,10 @@ int ntfs_collate_names(wchar_t *upcase, __u32 upcase_len,
  * if @s1 (or the first @n Unicode characters thereof) is found, respectively,
  * to be less than, to match, or be greater than @s2.
  */
-int ntfs_wcsncasecmp(wchar_t *s1, wchar_t *s2, size_t n,
-		     wchar_t *upcase, __u32 upcase_size)
+int ntfs_ucsncasecmp(const uchar_t *s1, const uchar_t *s2, size_t n,
+		     const uchar_t *upcase, const u32 upcase_size)
 {
-	wchar_t c1, c2;
+	uchar_t c1, c2;
 	size_t i;
 
 	for (i = 0; i < n; ++i) {
@@ -166,3 +198,184 @@ int ntfs_wcsncasecmp(wchar_t *s1, wchar_t *s2, size_t n,
 	return 0;
 }
 
+void ntfs_upcase_name(uchar_t *name, u32 name_len, const uchar_t *upcase,
+		const u32 upcase_len)
+{
+	u32 i;
+	uchar_t u;
+
+	for (i = 0; i < name_len; i++)
+		if ((u = le16_to_cpu(name[i])) < upcase_len)
+			name[i] = upcase[u];
+}
+
+void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr,
+		const uchar_t *upcase, const u32 upcase_len)
+{
+	ntfs_upcase_name((uchar_t*)&file_name_attr->file_name,
+			file_name_attr->file_name_length, upcase, upcase_len);
+}
+
+int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1,
+		FILE_NAME_ATTR *file_name_attr2,
+		const int err_val, const IGNORE_CASE_BOOL ic,
+		const uchar_t *upcase, const u32 upcase_len)
+{
+	return ntfs_collate_names((uchar_t*)&file_name_attr1->file_name,
+			file_name_attr1->file_name_length,
+			(uchar_t*)&file_name_attr2->file_name,
+			file_name_attr2->file_name_length,
+			err_val, ic, upcase, upcase_len);
+}
+
+/**
+ * ntfs_nlstoucs - convert NLS string to little endian Unicode string
+ * @vol:	ntfs volume which we are working with
+ * @ins:	input NLS string buffer
+ * @ins_len:	length of input string in bytes
+ * @outs:	on return contains the allocated output Unicode string buffer
+ *
+ * Convert the input string @ins, which is in whatever format the loaded NLS
+ * map dictates, into a little endian, 2-byte Unicode string.
+ *
+ * This function allocates the string and the caller is responsible for
+ * calling kmem_cache_free(ntfs_name_cache, @outs); when finished with it.
+ *
+ * On success the function returns the number of Unicode characters written to
+ * the output string *@outs (>= 0), not counting the terminating Unicode NULL
+ * character. *@outs is set to the allocated output string buffer.
+ *
+ * On error, a negative number corresponding to the error code is returned. In
+ * that case the output string is not allocated. Both *@outs and *@outs_len
+ * are then undefined.
+ *
+ * This might look a bit odd due to fast path optimization...
+ */
+int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins,
+		const int ins_len, uchar_t **outs)
+{
+	struct nls_table *nls = vol->nls_map;
+	uchar_t *ucs;
+	wchar_t wc;
+	int i, o, wc_len;
+
+	/* We don't trust outside sources. */
+	if (ins) {
+		ucs = (uchar_t*)kmem_cache_alloc(ntfs_name_cache, SLAB_NOFS);
+		if (ucs) {
+			for (i = o = 0; i < ins_len; i += wc_len) {
+				wc_len = nls->char2uni(ins + i, ins_len - i,
+						&wc);
+				if (wc_len >= 0) {
+					if (wc) {
+						ucs[o++] = cpu_to_le16(wc);
+						continue;
+					} /* else (!wc) */
+					break;
+				} /* else (wc_len < 0) */
+				goto conversion_err;
+			}
+			ucs[o] = cpu_to_le16('\0');
+			*outs = ucs;
+			return o;
+		} /* else (!ucs) */
+		ntfs_error(vol->sb, "Failed to allocate name from "
+				"ntfs_name_cache!");
+		return -ENOMEM;
+	} /* else (!ins) */
+	ntfs_error(NULL, "Received NULL pointer.");
+	return -EINVAL;
+conversion_err:
+	ntfs_error(vol->sb, "Name using character set %s contains characters "
+			"that cannot be converted to Unicode.", nls->charset);
+	kmem_cache_free(ntfs_name_cache, ucs);
+	return -EILSEQ;
+}
+
+/**
+ * ntfs_ucstonls - convert little endian Unicode string to NLS string
+ * @vol:	ntfs volume which we are working with
+ * @ins:	input Unicode string buffer
+ * @ins_len:	length of input string in Unicode characters
+ * @outs:	on return contains the (allocated) output NLS string buffer
+ * @outs_len:	length of output string buffer in bytes
+ *
+ * Convert the input little endian, 2-byte Unicode string @ins, of length
+ * @ins_len into the string format dictated by the loaded NLS.
+ *
+ * If @outs is NULL, this function allocates the string and the caller is
+ * responsible for calling kfree(@outs); when finished with it.
+ *
+ * On success the function returns the number of bytes written to the output
+ * string *@outs (>= 0), not counting the terminating NULL byte. If the output
+ * string buffer was allocated, *@outs is set to it.
+ *
+ * On error, a negative number corresponding to the error code is returned. In
+ * that case the output string is not allocated. The contents of *@outs are
+ * then undefined.
+ *
+ * This might look a bit odd due to fast path optimization...
+ */
+int ntfs_ucstonls(const ntfs_volume *vol, const uchar_t *ins,
+		const int ins_len, unsigned char **outs, int outs_len)
+{
+	struct nls_table *nls = vol->nls_map;
+	unsigned char *ns;
+	int i, o, ns_len, wc;
+
+	/* We don't trust outside sources. */
+	if (ins) {
+		ns = *outs;
+		ns_len = outs_len;
+		if (!ns_len) {
+			wc = -ENAMETOOLONG;
+			goto conversion_err;
+		}
+		if (!ns) {
+			ns_len = ins_len * 3;
+			ns = (unsigned char*)kmalloc(ns_len, GFP_NOFS);
+			if (!ns)
+				goto mem_err_out;
+		}
+		for (i = o = 0; i < ins_len; i++) {
+retry:			wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o,
+					ns_len - o);
+			if (wc > 0) {
+				o += wc;
+				continue;
+			} else if (!wc)
+				break;
+			else if (wc == -ENAMETOOLONG && ns != *outs) {
+				unsigned char *tc;
+				/* Grow by 64 bytes. (Chosen at random.) */
+				tc = (unsigned char*)kmalloc(ns_len + 64,
+						GFP_NOFS);
+				if (tc) {
+					memcpy(tc, ns, ns_len);
+					ns_len += 64;
+					kfree(ns);
+					ns = tc;
+					goto retry;
+				} /* No memory so goto conversion_error; */
+			} /* wc < 0, real error. */
+			goto conversion_err;
+		}
+		ns[o] = '\0';
+		*outs = ns;
+		return o;
+	} /* else (!ins) */
+	ntfs_error(NULL, "Received NULL pointer.");
+	return -EINVAL;
+conversion_err:
+	ntfs_error(vol->sb, "Unicode name contains characters that cannot be "
+			"converted to character set %s.", nls->charset);
+	if (ns != *outs)
+		kfree(ns);
+	if (wc != -ENAMETOOLONG)
+		wc = -EILSEQ;
+	return wc;
+mem_err_out:
+	ntfs_error(vol->sb, "Failed to allocate name!");
+	return -ENOMEM;
+}
+

fs/ntfs/upcase.c

+/*
+ * upcase.c - Generate the full NTFS Unicode upcase table in little endian.
+ *	      Part of the Linux-NTFS project.
+ *
+ * Copyright (C) 2001 Richard Russon <ntfs@flatcap.org>
+ * Copyright (c) 2001 Anton Altaparmakov <aia21@cam.ac.uk>
+ *
+ * Modified for mkntfs inclusion 9 June 2001 by Anton Altaparmakov.
+ * Modified for kernel inclusion 10 September 2001 by Anton Altparmakov.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS source
+ * in the file COPYING); if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "ntfs.h"
+
+uchar_t *generate_default_upcase(void)
+{
+	const int uc_run_table[][3] = { /* Start, End, Add */
+	{0x0061, 0x007B,  -32}, {0x0451, 0x045D, -80}, {0x1F70, 0x1F72,  74},
+	{0x00E0, 0x00F7,  -32}, {0x045E, 0x0460, -80}, {0x1F72, 0x1F76,  86},
+	{0x00F8, 0x00FF,  -32}, {0x0561, 0x0587, -48}, {0x1F76, 0x1F78, 100},
+	{0x0256, 0x0258, -205}, {0x1F00, 0x1F08,   8}, {0x1F78, 0x1F7A, 128},
+	{0x028A, 0x028C, -217}, {0x1F10, 0x1F16,   8}, {0x1F7A, 0x1F7C, 112},
+	{0x03AC, 0x03AD,  -38}, {0x1F20, 0x1F28,   8}, {0x1F7C, 0x1F7E, 126},
+	{0x03AD, 0x03B0,  -37}, {0x1F30, 0x1F38,   8}, {0x1FB0, 0x1FB2,   8},
+	{0x03B1, 0x03C2,  -32}, {0x1F40, 0x1F46,   8}, {0x1FD0, 0x1FD2,   8},
+	{0x03C2, 0x03C3,  -31}, {0x1F51, 0x1F52,   8}, {0x1FE0, 0x1FE2,   8},
+	{0x03C3, 0x03CC,  -32}, {0x1F53, 0x1F54,   8}, {0x1FE5, 0x1FE6,   7},
+	{0x03CC, 0x03CD,  -64}, {0x1F55, 0x1F56,   8}, {0x2170, 0x2180, -16},
+	{0x03CD, 0x03CF,  -63}, {0x1F57, 0x1F58,   8}, {0x24D0, 0x24EA, -26},
+	{0x0430, 0x0450,  -32}, {0x1F60, 0x1F68,   8}, {0xFF41, 0xFF5B, -32},
+	{0}
+	};
+
+	const int uc_dup_table[][2] = { /* Start, End */
+	{0x0100, 0x012F}, {0x01A0, 0x01A6}, {0x03E2, 0x03EF}, {0x04CB, 0x04CC},
+	{0x0132, 0x0137}, {0x01B3, 0x01B7}, {0x0460, 0x0481}, {0x04D0, 0x04EB},
+	{0x0139, 0x0149}, {0x01CD, 0x01DD}, {0x0490, 0x04BF}, {0x04EE, 0x04F5},
+	{0x014A, 0x0178}, {0x01DE, 0x01EF}, {0x04BF, 0x04BF}, {0x04F8, 0x04F9},
+	{0x0179, 0x017E}, {0x01F4, 0x01F5}, {0x04C1, 0x04C4}, {0x1E00, 0x1E95},
+	{0x018B, 0x018B}, {0x01FA, 0x0218}, {0x04C7, 0x04C8}, {0x1EA0, 0x1EF9},
+	{0}
+	};
+
+	const int uc_word_table[][2] = { /* Offset, Value */
+	{0x00FF, 0x0178}, {0x01AD, 0x01AC}, {0x01F3, 0x01F1}, {0x0269, 0x0196},
+	{0x0183, 0x0182}, {0x01B0, 0x01AF}, {0x0253, 0x0181}, {0x026F, 0x019C},
+	{0x0185, 0x0184}, {0x01B9, 0x01B8}, {0x0254, 0x0186}, {0x0272, 0x019D},
+	{0x0188, 0x0187}, {0x01BD, 0x01BC}, {0x0259, 0x018F}, {0x0275, 0x019F},
+	{0x018C, 0x018B}, {0x01C6, 0x01C4}, {0x025B, 0x0190}, {0x0283, 0x01A9},
+	{0x0192, 0x0191}, {0x01C9, 0x01C7}, {0x0260, 0x0193}, {0x0288, 0x01AE},
+	{0x0199, 0x0198}, {0x01CC, 0x01CA}, {0x0263, 0x0194}, {0x0292, 0x01B7},
+	{0x01A8, 0x01A7}, {0x01DD, 0x018E}, {0x0268, 0x0197},
+	{0}
+	};
+
+	int i, r;
+	uchar_t *uc;
+
+	uc = ntfs_malloc_nofs(default_upcase_len * sizeof(uchar_t));
+	if (!uc)
+		return uc;
+	memset(uc, 0, default_upcase_len * sizeof(uchar_t));
+	for (i = 0; i < default_upcase_len; i++)
+		uc[i] = cpu_to_le16(i);
+	for (r = 0; uc_run_table[r][0]; r++)
+		for (i = uc_run_table[r][0]; i < uc_run_table[r][1]; i++)
+			uc[i] = cpu_to_le16((le16_to_cpu(uc[i]) +
+					uc_run_table[r][2]));
+	for (r = 0; uc_dup_table[r][0]; r++)
+		for (i = uc_dup_table[r][0]; i < uc_dup_table[r][1]; i += 2)
+			uc[i + 1] = cpu_to_le16(le16_to_cpu(uc[i + 1]) - 1);
+	for (r = 0; uc_word_table[r][0]; r++)
+		uc[uc_word_table[r][0]] = cpu_to_le16(uc_word_table[r][1]);
+	return uc;
+}
+

fs/ntfs/util.c

-/*
- * util.c -  Miscellaneous support
- *
- * Copyright (C) 1997,1999 Martin von Lwis
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
- *
- * The utf8 routines are copied from Python wstrop module.
- */
-
-#include "ntfstypes.h"
-#include "struct.h"
-#include "util.h"
-#include <linux/string.h>
-#include <linux/errno.h>
-#include <asm/div64.h>		/* For do_div(). */
-#include "support.h"
-
-/*
- * Converts a single wide character to a sequence of utf8 bytes.
- * The character is represented in host byte order.
- * Returns the number of bytes, or 0 on error.
- */
-static int to_utf8(ntfs_u16 c, unsigned char *buf)
-{
-	if (c == 0)
-		return 0; /* No support for embedded 0 runes. */
-	if (c < 0x80) {
-		if (buf)
-			buf[0] = (unsigned char)c;
-		return 1;
-	}
-	if (c < 0x800) {
-		if (buf) {
-			buf[0] = 0xc0 | (c >> 6);
-			buf[1] = 0x80 | (c & 0x3f);
-		}
-		return 2;
-	}
-	/* c < 0x10000 */
-	if (buf) {
-		buf[0] = 0xe0 | (c >> 12);
-		buf[1] = 0x80 | ((c >> 6) & 0x3f);
-		buf[2] = 0x80 | (c & 0x3f);
-	}
-	return 3;
-}
-
-/*
- * Decodes a sequence of utf8 bytes into a single wide character.
- * The character is returned in host byte order.
- * Returns the number of bytes consumed, or 0 on error.
- */
-static int from_utf8(const unsigned char *str, ntfs_u16 *c)
-{
-	int l = 0, i;
-
-	if (*str < 0x80) {
-		*c = *str;
-		return 1;
-	}
-	if (*str < 0xc0)	/* Lead byte must not be 10xxxxxx. */
-		return 0;	/* Is c0 a possible lead byte? */
-	if (*str < 0xe0) {		/* 110xxxxx */
-		*c = *str & 0x1f;
-		l = 2;
-	} else if (*str < 0xf0) {	/* 1110xxxx */
-		*c = *str & 0xf;
-		l = 3;
-	} else if (*str < 0xf8) {   	/* 11110xxx */
-		*c = *str & 7;
-		l = 4;
-	} else /* We don't support characters above 0xFFFF in NTFS. */
-		return 0;
-	for (i = 1; i < l; i++) {
-		/* All other bytes must be 10xxxxxx. */
-		if ((str[i] & 0xc0) != 0x80)
-			return 0;
-		*c <<= 6;
-		*c |= str[i] & 0x3f;
-	}
-	return l;
-}
-
-/*
- * Converts wide string to UTF-8. Expects two in- and two out-parameters.
- * Returns 0 on success, or error code. 
- * The caller has to free the result string.
- */
-static int ntfs_dupuni2utf8(ntfs_u16 *in, int in_len, char **out, int *out_len)
-{
-	int i, tmp;
-	int len8;
-	unsigned char *result;
-
-	ntfs_debug(DEBUG_NAME1, "converting l = %d\n", in_len);
-	/* Count the length of the resulting UTF-8. */
-	for (i = len8 = 0; i < in_len; i++) {
-		tmp = to_utf8(NTFS_GETU16(in + i), 0);
-		if (!tmp)
-			/* Invalid character. */
-			return -EILSEQ;
-		len8 += tmp;
-	}
-	*out = result = ntfs_malloc(len8 + 1); /* allow for zero-termination */
-	if (!result)
-		return -ENOMEM;
-	result[len8] = '\0';
-	*out_len = len8;
-	for (i = len8 = 0; i < in_len; i++)
-		len8 += to_utf8(NTFS_GETU16(in + i), result + len8);
-	ntfs_debug(DEBUG_NAME1, "result %p:%s\n", result, result);
-	return 0;
-}
-
-/*
- * Converts an UTF-8 sequence to a wide string. Same conventions as the
- * previous function.
- */
-static int ntfs_duputf82uni(unsigned char* in, int in_len, ntfs_u16** out,
-		int *out_len)
-{
-	int i, tmp;
-	int len16;
-	ntfs_u16* result;
-	ntfs_u16 wtmp;
-
-	for (i = len16 = 0; i < in_len; i += tmp, len16++) {
-		tmp = from_utf8(in + i, &wtmp);
-		if (!tmp)
-			return -EILSEQ;
-	}
-	*out = result = ntfs_malloc(2 * (len16 + 1));
-	if (!result)
-		return -ENOMEM;
-	result[len16] = 0;
-	*out_len = len16;
-	for (i = len16 = 0; i < in_len; i += tmp, len16++) {
-		tmp = from_utf8(in + i, &wtmp);
-		NTFS_PUTU16(result + len16, wtmp);
-	}
-	return 0;
-}
-
-/* Encodings dispatchers. */
-int ntfs_encodeuni(ntfs_volume *vol, ntfs_u16 *in, int in_len, char **out,
-		int *out_len)
-{
-	if (vol->nls_map)
-		return ntfs_dupuni2map(vol, in, in_len, out, out_len);
-	else
-		return ntfs_dupuni2utf8(in, in_len, out, out_len);
-}
-
-int ntfs_decodeuni(ntfs_volume *vol, char *in, int in_len, ntfs_u16 **out,
-		int *out_len)
-{
-	if (vol->nls_map)
-		return ntfs_dupmap2uni(vol, in, in_len, out, out_len);
-	else
-		return ntfs_duputf82uni(in, in_len, out, out_len);
-}
-
-/* Same address space copies. */
-void ntfs_put(ntfs_io *dest, void *src, ntfs_size_t n)
-{
-	ntfs_memcpy(dest->param, src, n);
-	((char*)dest->param) += n;
-}
-
-void ntfs_get(void* dest, ntfs_io *src, ntfs_size_t n)
-{
-	ntfs_memcpy(dest, src->param, n);
-	((char*)src->param) += n;
-}
-
-void *ntfs_calloc(int size)
-{
-	void *result = ntfs_malloc(size);
-	if (result)
-		ntfs_bzero(result, size);
-	return result;
-}
-
-/* Copy len ascii characters from from to to. :) */
-void ntfs_ascii2uni(short int *to, char *from, int len)
-{
-	int i;
-
-	for (i = 0; i < len; i++)
-		NTFS_PUTU16(to + i, from[i]);
-	to[i] = 0;
-}
-
-/* strncmp for Unicode strings. */
-int ntfs_uni_strncmp(short int* a, short int *b, int n)
-{
-	int i;
-
-	for(i = 0; i < n; i++)
-	{
-		if (NTFS_GETU16(a + i) < NTFS_GETU16(b + i))
-			return -1;
-		if (NTFS_GETU16(b + i) < NTFS_GETU16(a + i))
-			return 1;
-		if (NTFS_GETU16(a + i) == 0)
-			break;
-	}
-	return 0;
-}
-
-/* strncmp between Unicode and ASCII strings. */
-int ntfs_ua_strncmp(short int* a, char* b, int n)
-{
-	int i;
-
-	for (i = 0; i < n; i++)	{
-		if(NTFS_GETU16(a + i) < b[i])
-			return -1;
-		if(b[i] < NTFS_GETU16(a + i))
-			return 1;
-		if (b[i] == 0)
-			return 0;
-	}
-	return 0;
-}
-
-#define NTFS_TIME_OFFSET ((ntfs_time64_t)(369*365 + 89) * 24 * 3600 * 10000000)
-
-/* Convert the NT UTC (based 1.1.1601, in hundred nanosecond units)
- * into Unix UTC (based 1.1.1970, in seconds). */
-ntfs_time_t ntfs_ntutc2unixutc(ntfs_time64_t ntutc)
-{
-	/* Subtract the NTFS time offset, then convert to 1s intervals. */
-	ntfs_time64_t t = ntutc - NTFS_TIME_OFFSET;
-	do_div(t, 10000000);
-	return (ntfs_time_t)t;
-}
-
-/* Convert the Unix UTC into NT UTC. */
-ntfs_time64_t ntfs_unixutc2ntutc(ntfs_time_t t)
-{
-	/* Convert to 100ns intervals and then add the NTFS time offset. */
-	return (ntfs_time64_t)t * 10000000 + NTFS_TIME_OFFSET;
-}
-
-#undef NTFS_TIME_OFFSET
-
-/* Fill index name. */
-void ntfs_indexname(char *buf, int type)
-{
-	char hex[] = "0123456789ABCDEF";
-	int index;
-	*buf++ = '$';
-	*buf++ = 'I';
-	for (index = 24; index > 0; index -= 4)
-		if ((0xF << index) & type)
-			break;
-	while (index >= 0) {
-		*buf++ = hex[(type >> index) & 0xF];
-		index -= 4;
-	}
-	*buf = '\0';
-}
-

fs/ntfs/util.h

-/*
- * util.h - Header file for util.c
- *
- * Copyright (C) 1997 Rgis Duchesne
- * Copyright (C) 2001 Anton Altaparmakov (AIA)
- */
-
-/* The first 16 inodes correspond to NTFS special files. */
-typedef enum {
-	FILE_Mft	= 0,
-	FILE_MftMirr	= 1,
-	FILE_LogFile	= 2,
-	FILE_Volume	= 3,
-	FILE_AttrDef	= 4,
-	FILE_root	= 5,
-	FILE_BitMap	= 6,
-	FILE_Boot	= 7,
-	FILE_BadClus	= 8,
-	FILE_Secure	= 9,
-	FILE_UpCase	= 10,
-	FILE_Extend	= 11,
-	FILE_Reserved12	= 12,
-	FILE_Reserved13	= 13,
-	FILE_Reserved14	= 14,
-	FILE_Reserved15	= 15,
-} NTFS_SYSTEM_FILES;
- 
-/* Memory management */
-void *ntfs_calloc(int size);
-
-/* String operations */
-/*  Copy Unicode <-> ASCII */
-void ntfs_ascii2uni(short int *to, char *from, int len);
-
-/*  Comparison */
-int ntfs_uni_strncmp(short int* a, short int *b, int n);
-int ntfs_ua_strncmp(short int* a, char* b, int n);
-
-/* Same address space copies */
-void ntfs_put(ntfs_io *dest, void *src, ntfs_size_t n);
-void ntfs_get(void* dest, ntfs_io *src, ntfs_size_t n);
-
-/* Charset conversion */
-int ntfs_encodeuni(ntfs_volume *vol, ntfs_u16 *in, int in_len, char **out,
-		   int *out_len);
-int ntfs_decodeuni(ntfs_volume *vol, char *in, int in_len, ntfs_u16 **out,
-		   int *out_len);
-
-/* Time conversion */
-/*  NT <-> Unix */
-ntfs_time_t ntfs_ntutc2unixutc(ntfs_time64_t ntutc);
-ntfs_time64_t ntfs_unixutc2ntutc(ntfs_time_t t);
-
-/* Attribute names */
-void ntfs_indexname(char *buf, int type);
-

fs/ntfs/volume.h

+/*
+ * volume.h - Defines for volume structures in NTFS Linux kernel driver. Part
+ *	      of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001,2002 Anton Altaparmakov.
+ * Copyright (C) 2002 Richard Russon.
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be 
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS 
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_VOLUME_H
+#define _LINUX_NTFS_VOLUME_H
+
+#include "types.h"
+
+/* These are used to determine which inode names are returned by readdir(). */
+typedef enum {
+	SHOW_SYSTEM	= 1,
+	SHOW_WIN32	= 2,
+	SHOW_DOS	= 4,
+	SHOW_POSIX	= SHOW_WIN32 | SHOW_DOS,
+	SHOW_ALL	= SHOW_SYSTEM | SHOW_POSIX,
+} READDIR_OPTIONS;
+
+#define RHideSystemFiles(x)	(!((x) & SHOW_SYSTEM))
+#define RHideLongNames(x)	(!((x) & SHOW_WIN32))
+#define RHideDosNames(x)	(!((x) & SHOW_DOS))
+
+/*
+ * The NTFS in memory super block structure.
+ */
+typedef struct {
+	/*
+	 * FIXME: Reorder to have commonly used together element within the
+	 * same cache line, aiming at a cache line size of 32 bytes. Aim for
+	 * 64 bytes for less commonly used together elements. Put most commonly
+	 * used elements to front of structure. Obviously do this only when the
+	 * structure has stabilized... (AIA)
+	 */
+	/* Device specifics. */
+	struct super_block *sb;		/* Pointer back to the super_block,
+					   so we don't have to get the offset
+					   every time. */
+	LCN nr_blocks;			/* Number of NTFS_BLOCK_SIZE bytes
+					   sized blocks on the device. */
+	/* Configuration provided by user at mount time. */
+	uid_t uid;			/* uid that files will be mounted as. */
+	gid_t gid;			/* gid that files will be mounted as. */
+	mode_t fmask;			/* The mask for file permissions. */
+	mode_t dmask;			/* The mask for directory
+					   permissions. */
+	READDIR_OPTIONS readdir_opts;	/* Namespace of inode names to show. */
+	u8 mft_zone_multiplier;	/* Initial mft zone multiplier. */
+	u8 on_errors;			/* What to do on file system errors. */
+	/* NTFS bootsector provided information. */
+	u16 sector_size;		/* in bytes */
+	u8 sector_size_bits;		/* log2(sector_size) */
+	u32 cluster_size;		/* in bytes */
+	u32 cluster_size_mask;		/* cluster_size - 1 */
+	u8 cluster_size_bits;		/* log2(cluster_size) */
+	u32 mft_record_size;		/* in bytes */
+	u32 mft_record_size_mask;	/* mft_record_size - 1 */
+	u8 mft_record_size_bits;	/* log2(mft_record_size) */
+	u32 index_record_size;		/* in bytes */
+	u32 index_record_size_mask;	/* index_record_size - 1 */
+	u8 index_record_size_bits;	/* log2(index_record_size) */
+	union {
+		LCN nr_clusters;	/* Volume size in clusters. */
+		LCN nr_lcn_bits;	/* Number of bits in lcn bitmap. */
+	} SN(vcl);
+	LCN mft_lcn;			/* Cluster location of mft data. */
+	LCN mftmirr_lcn;		/* Cluster location of copy of mft. */
+	u64 serial_no;			/* The volume serial number. */
+	/* Mount specific NTFS information. */
+	u32 upcase_len;			/* Number of entries in upcase[]. */
+	uchar_t *upcase;		/* The upcase table. */
+	LCN mft_zone_start;		/* First cluster of the mft zone. */
+	LCN mft_zone_end;		/* First cluster beyond the mft zone. */
+	struct inode *mft_ino;		/* The VFS inode of $MFT. */
+	struct rw_semaphore mftbmp_lock; /* Lock for serializing accesses to the
+					    mft record bitmap ($MFT/$BITMAP). */
+	union {
+		s64 nr_mft_records;	/* Number of records in the mft. */
+		s64 nr_mft_bits;	/* Number of bits in mft bitmap. */
+	} SN(vmm);
+	struct address_space mftbmp_mapping; /* Page cache for $MFT/$BITMAP. */
+	run_list mftbmp_rl;		/* Run list for $MFT/$BITMAP. */
+	s64 mftbmp_size;		/* Data size of $MFT/$BITMAP. */
+	s64 mftbmp_initialized_size;	/* Initialized size of $MFT/$BITMAP. */
+	s64 mftbmp_allocated_size;	/* Allocated size of $MFT/$BITMAP. */
+	struct inode *mftmirr_ino;	/* The VFS inode of $MFTMirr. */
+	struct inode *lcnbmp_ino;	/* The VFS inode of $Bitmap. */
+	struct rw_semaphore lcnbmp_lock; /* Lock for serializing accesses to the
+					    cluster bitmap ($Bitmap/$DATA). */
+	struct inode *vol_ino;		/* The VFS inode of $Volume. */
+	unsigned long vol_flags;	/* Volume flags (VOLUME_*). */
+	u8 major_ver;			/* Ntfs major version of volume. */
+	u8 minor_ver;			/* Ntfs minor version of volume. */
+	struct inode *root_ino;		/* The VFS inode of the root
+					   directory. */
+	struct inode *secure_ino;	/* The VFS inode of $Secure (NTFS3.0+
+					   only, otherwise NULL). */
+	struct nls_table *nls_map;
+} ntfs_volume;
+
+#define _VCL(X)  SC(vcl,X)
+#define _VMM(X)  SC(vmm,X)
+
+#endif /* _LINUX_NTFS_VOLUME_H */
+

include/linux/fs.h

@@ -647,7 +647,6 @@ struct quota_mount_options
 
 #include <linux/ext3_fs_sb.h>
 #include <linux/hpfs_fs_sb.h>
-#include <linux/ntfs_fs_sb.h>
 #include <linux/msdos_fs_sb.h>
 #include <linux/iso_fs_sb.h>
 #include <linux/sysv_fs_sb.h>
@@ -699,7 +698,6 @@ struct super_block {
 	union {
 		struct ext3_sb_info	ext3_sb;
 		struct hpfs_sb_info	hpfs_sb;
-		struct ntfs_sb_info	ntfs_sb;
 		struct msdos_sb_info	msdos_sb;
 		struct isofs_sb_info	isofs_sb;
 		struct sysv_sb_info	sysv_sb;

include/linux/ntfs_fs.h

-#ifndef _LINUX_NTFS_FS_H
-#define _LINUX_NTFS_FS_H
-
-#include <asm/byteorder.h>
-
-#define NTFS_SECTOR_BITS 9
-#define NTFS_SECTOR_SIZE 512
-
-/*
- * Attribute flags (16-bit).
- */
-typedef enum {
-	ATTR_IS_COMPRESSED      = __constant_cpu_to_le16(0x0001),
-	ATTR_COMPRESSION_MASK   = __constant_cpu_to_le16(0x00ff),
-					/* Compression method mask. Also,
-					 * first illegal value. */
-	ATTR_IS_ENCRYPTED       = __constant_cpu_to_le16(0x4000),
-	ATTR_IS_SPARSE          = __constant_cpu_to_le16(0x8000),
-} __attribute__ ((__packed__)) ATTR_FLAGS;
-
-/*
- * The two zones from which to allocate clusters.
- */
-typedef enum {
-	MFT_ZONE,
-	DATA_ZONE
-} NTFS_CLUSTER_ALLOCATION_ZONES;
-
-#endif

include/linux/ntfs_fs_i.h

-#ifndef _LINUX_NTFS_FS_I_H
-#define _LINUX_NTFS_FS_I_H
-
-#include <linux/types.h>
-
-/* Forward declarations, to keep number of mutual includes low */
-struct ntfs_attribute;
-struct ntfs_sb_info;
-
-/* Duplicate definitions from ntfs/ntfstypes.h */
-#ifndef NTFS_INTEGRAL_TYPES
-#define NTFS_INTEGRAL_TYPES
-typedef u8  ntfs_u8;
-typedef u16 ntfs_u16;
-typedef u32 ntfs_u32;
-typedef u64 ntfs_u64;
-typedef s8  ntfs_s8;
-typedef s16 ntfs_s16;
-typedef s32 ntfs_s32;
-typedef s64 ntfs_s64;
-#endif
-
-#ifndef NTMODE_T
-#define NTMODE_T
-typedef __kernel_mode_t ntmode_t;
-#endif
-#ifndef NTFS_UID_T
-#define NTFS_UID_T
-typedef uid_t ntfs_uid_t;
-#endif
-#ifndef NTFS_GID_T
-#define NTFS_GID_T
-typedef gid_t ntfs_gid_t;
-#endif
-#ifndef NTFS_SIZE_T
-#define NTFS_SIZE_T
-typedef __kernel_size_t ntfs_size_t;
-#endif
-#ifndef NTFS_TIME_T
-#define NTFS_TIME_T
-typedef __kernel_time_t ntfs_time_t;
-#endif
-
-/* unicode character type */
-#ifndef NTFS_WCHAR_T
-#define NTFS_WCHAR_T
-typedef u16 ntfs_wchar_t;
-#endif
-/* file offset */
-#ifndef NTFS_OFFSET_T
-#define NTFS_OFFSET_T
-typedef s64 ntfs_offset_t;
-#endif
-/* UTC */
-#ifndef NTFS_TIME64_T
-#define NTFS_TIME64_T
-typedef u64 ntfs_time64_t;
-#endif
-/*
- * This is really signed long long. So we support only volumes up to 2Tb. This
- * is ok as Win2k also only uses 32-bits to store clusters.
- * Whatever you do keep this a SIGNED value or a lot of NTFS users with
- * corrupted filesystems will lynch you! It causes massive fs corruption when
- * unsigned due to the nature of many checks relying on being performed on
- * signed quantities. (AIA)
- */
-#ifndef NTFS_CLUSTER_T
-#define NTFS_CLUSTER_T
-typedef s32 ntfs_cluster_t;
-#endif
-
-/* Definition of the NTFS in-memory inode structure. */
-struct ntfs_inode_info {
-	struct ntfs_sb_info *vol;
-	unsigned long i_number;		/* Should be really 48 bits. */
-	__u16 sequence_number;		/* The current sequence number. */
-	unsigned char *attr;		/* Array of the attributes. */
-	int attr_count;			/* Size of attrs[]. */
-	struct ntfs_attribute *attrs;
-	int record_count;		/* Size of records[]. */
-	int *records; /* Array of the record numbers of the $Mft whose 
-		       * attributes have been inserted in the inode. */
-	union {
-		struct {
-			int recordsize;
-			int clusters_per_record;
-		} index;
-	} u;	
-};
-
-/* this is a kludge */
-struct ntfs_i {
-	struct ntfs_inode_info n;
-	struct inode vfs_inode;
-};
-
-#endif

include/linux/ntfs_fs_sb.h

-#ifndef _LINUX_NTFS_FS_SB_H
-#define _LINUX_NTFS_FS_SB_H
-
-#include <linux/ntfs_fs_i.h>
-
-struct ntfs_sb_info{
-	/* Configuration provided by user at mount time. */
-	ntfs_uid_t uid;
-	ntfs_gid_t gid;
-	ntmode_t umask;
-	void *nls_map;
-	unsigned int ngt;
-	char mft_zone_multiplier;
-	unsigned long mft_data_pos;
-	ntfs_cluster_t mft_zone_pos;
-	ntfs_cluster_t mft_zone_start;
-	ntfs_cluster_t mft_zone_end;
-	ntfs_cluster_t data1_zone_pos;
-	ntfs_cluster_t data2_zone_pos;
-	/* Configuration provided by user with the ntfstools.
-	 * FIXME: This is no longer possible. What is this good for? (AIA) */
-	ntfs_size_t partition_bias;	/* For access to underlying device. */
-	/* Attribute definitions. */
-	ntfs_u32 at_standard_information;
-	ntfs_u32 at_attribute_list;
-	ntfs_u32 at_file_name;
-	ntfs_u32 at_volume_version;
-	ntfs_u32 at_security_descriptor;
-	ntfs_u32 at_volume_name;
-	ntfs_u32 at_volume_information;
-	ntfs_u32 at_data;
-	ntfs_u32 at_index_root;
-	ntfs_u32 at_index_allocation;
-	ntfs_u32 at_bitmap;
-	ntfs_u32 at_symlink; /* aka SYMBOLIC_LINK or REPARSE_POINT */
-	/* Data read / calculated from the boot file. */
-	int sector_size;
-	int cluster_size;
-	int cluster_size_bits;
-	int mft_clusters_per_record;
-	int mft_record_size;
-	int mft_record_size_bits;
-	int index_clusters_per_record;
-	int index_record_size;
-	int index_record_size_bits;
-	ntfs_cluster_t nr_clusters;
-	ntfs_cluster_t mft_lcn;
-	ntfs_cluster_t mft_mirr_lcn;
-	/* Data read from special files. */
-	unsigned char *mft;
-	unsigned short *upcase;
-	unsigned int upcase_length;
-	/* Inodes we always hold onto. */
-	struct ntfs_inode_info *mft_ino;
-	struct ntfs_inode_info *mftmirr;
-	struct ntfs_inode_info *bitmap;
-	struct super_block *sb;
-	unsigned char ino_flags;
-};
-
-#endif

kernel/ksyms.c

@@ -165,7 +165,8 @@ EXPORT_SYMBOL(d_alloc);
 EXPORT_SYMBOL(d_lookup);
 EXPORT_SYMBOL(__d_path);
 EXPORT_SYMBOL(mark_buffer_dirty);
-EXPORT_SYMBOL(set_buffer_async_io); /* for reiserfs_writepage */
+EXPORT_SYMBOL(end_buffer_io_sync);
+EXPORT_SYMBOL(set_buffer_async_io);
 EXPORT_SYMBOL(__mark_buffer_dirty);
 EXPORT_SYMBOL(__mark_inode_dirty);
 EXPORT_SYMBOL(get_empty_filp);