NTFS: 2.0.4 - Cleanups and updates for kernel 2.5.11.

- Add documentation on how to use the MD driver to be able to use NTFS
stripe and volume sets in Linux and generally cleanup documentation
a bit.

Remove all uses of kdev_t in favour of struct block_device *:
- Change compress.c::ntfs_file_read_compressed_block() to use sb_getblk()
instead of getblk().
- Change super.c::ntfs_fill_suoer() to use bdev_hardsect_size() instead
of get_hardsect_size().
- No need to get old blocksize in super.c::ntfs_fill_super() as
fs/super.c::get_sb_bdev() already does this.
- Set bh->b_bdev instead of bh->b_dev throughout aops.c.

Documentation/filesystems/ntfs.txt

-NTFS Overview
-=============
+The Linux NTFS filesystem driver
+================================
+
+
+Table of contents
+=================
+
+- Overview
+- Supported mount options
+- Features
+- Known bugs and (mis-)features
+- Using Software RAID with NTFS
+- Limitiations when using the MD driver
+- ChangeLog
+
+
+Overview
+========
 
 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.
+fault-tolerance or journalling supported.
+
+For fault tolerance and raid support (i.e. volume and stripe sets), you can use
+the kernel's Software RAID / MD driver. See section "Using Software RAID with
+NTFS" for details.
 
-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
-md driver can be talked into using the same layout as Windows NT. However,
-using the md driver will fail if any of your NTFS partitions have an odd
-number of sectors.
 
 Supported mount options
 =======================
 
+In addition to the generic mount options described by the manual page for the
+mount command (man 8 mount, also see man 5 fstab), the NTFS driver supports the
+following mount options:
+
 iocharset=name		Deprecated option. Still supported but please use
 			nls=name in the future. See description for nls=name.
 
@@ -137,6 +156,7 @@ mft_zone_multiplier=	Set the MFT zone multiplier for the volume (this
 				4		50%
 			Note this option is irrelevant for read-only mounts.
 
+
 Features
 ========
 
@@ -155,6 +175,7 @@ Features
   was unchanged but the time spent in the kernel was decreased by a factor of
   2.5 (from 85 CPU seconds down to 33).
 
+
 Known bugs and (mis-)features
 =============================
 
@@ -163,11 +184,86 @@ Known bugs and (mis-)features
 Please send bug reports/comments/feedback/abuse to the Linux-NTFS development
 list at sourceforge: linux-ntfs-dev@lists.sourceforge.net
 
+
+Using Software RAID with NTFS
+=============================
+
+For support of volume and stripe sets, use the kernel's Software RAID / MD
+driver and set up your /etc/raidtab appropriately (see man 5 raidtab).
+
+Linear volume sets, i.e. linear raid, as well as stripe sets, i.e. raid level 0,
+have been tested and work fine (though see section "Limitiations when using the
+MD driver with NTFS volumes" especially if you want to use linear raid). Even
+though untested, there is no reason why mirrors, i.e. raid level 1, and stripes
+with parity, i.e. raid level 5, should not work, too.
+
+You have to use the "persistent-superblock 0" option for each raid-disk in the
+NTFS volume/stripe you are configuring in /etc/raidtab as the persistent
+superblock used by the MD driver would damange the NTFS volume.
+
+Windows by default uses a stripe chunk size of 64k, so you probably want the
+"chunk-size 64k" option for each raid-disk, too.
+
+For example, if you have a stripe set consisting of two partitions /dev/hda5
+and /dev/hdb1 your /etc/raidtab would look like this:
+
+raiddev /dev/md0
+	raid-level	0
+	nr-raid-disks	2
+	nr-spare-disks	0
+	persistent-superblock	0
+	chunk-size	64k
+	device		/dev/hda5
+	raid-disk	0
+	device		/dev/hdb1
+	raid-disl	1
+
+For linear raid, just change the raid-level above to "raid-level linear", for
+mirrors, change it to "raid-level 1", and for stripe sets with parity, change
+it to "raid-level 5".
+
+Note for stripe sets with parity you will also need to tell the MD driver which
+parity algorithm to use by specifying the option "parity-algorithm which",
+where you need to replace "which" with the name of the algorithm to use (see
+man 5 raidtab for available algorithms) and you will have to try the different
+available algorithms until you find one that works. Make sure you are working
+read-only when playing with this as you may damage your data otherwise. If you
+find which algorithm works please let us know (email the linux-ntfs developers
+list linux-ntfs-dev@lists.sourceforge.net or drop in on IRC in channel #ntfs
+on the irc.openprojects.net network) so we can update this documentation.
+
+Once the raidtab is setup, run for example raid0run -a to start all devices or
+raid0run /dev/md0 to start a particular md device, in this case /dev/md0.
+
+Then just use the mount command as usual to mount the ntfs volume using for
+example:	mount -t ntfs -o ro /dev/md0 /mnt/myntfsvolume
+
+It is advisable to do the mount read-only to see if the md volume has been
+setup correctly to avoid the possibility of causing damage to the data on the
+ntfs volume.
+
+
+Limitiations when using the MD driver
+=====================================
+
+Using the md driver will not work properly if any of your NTFS partitions have
+an odd number of sectors. This is especially important for linear raid as all
+data after the first partition with an odd number of sectors will be offset by
+one or more sectors so if you mount such a partition with write support you
+will cause massive damage to the data on the volume which will only become
+apparent when you try to use the volume again under Windows.
+
+So when using linear raid, make sure that all your partitions have an even
+number of sectors BEFORE attempting to use it. You have been warned!
+
+
 ChangeLog
 =========
 
 Note that a technical ChangeLog aimed at kernel hackers is in fs/ntfs/ChangeLog.
 
+2.0.4:
+	- Cleanups and updates for kernel 2.5.11.
 2.0.3:
 	- Small bug fixes, cleanups, and performance improvements.
 2.0.2:

fs/ntfs/ChangeLog

@@ -27,6 +27,20 @@ ToDo:
 	  quite big. Modularising them a bit, e.g. a-la get_block(), will make
 	  them cleaner and make code reuse easier.
 
+2.0.4 - Cleanups and updates for kernel 2.5.11.
+
+	- Add documentation on how to use the MD driver to be able to use NTFS
+	  stripe and volume sets in Linux and generally cleanup documentation
+	  a bit.
+	Remove all uses of kdev_t in favour of struct block_device *:
+	- Change compress.c::ntfs_file_read_compressed_block() to use
+	  sb_getblk() instead of getblk().
+	- Change super.c::ntfs_fill_suoer() to use bdev_hardsect_size() instead
+	  of get_hardsect_size().
+	- No need to get old blocksize in super.c::ntfs_fill_super() as
+	  fs/super.c::get_sb_bdev() already does this.
+	- Set bh->b_bdev instead of bh->b_dev throughout aops.c.
+
 2.0.3 - Small bug fixes, cleanups, and performance improvements.
 
 	- Remove some dead code from mft.c.

fs/ntfs/Makefile

@@ -2,12 +2,12 @@
 
 O_TARGET := ntfs.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-y   := aops.o attrib.o compress.o debug.o dir.o file.o inode.o mft.o \
+		mst.o namei.o super.o sysctl.o time.o unistr.o upcase.o
 
 obj-m   := $(O_TARGET)
 
-EXTRA_CFLAGS = -DNTFS_VERSION=\"2.0.3\"
+EXTRA_CFLAGS = -DNTFS_VERSION=\"2.0.4\"
 
 ifeq ($(CONFIG_NTFS_DEBUG),y)
 EXTRA_CFLAGS += -DDEBUG

fs/ntfs/aops.c

@@ -147,7 +147,7 @@ static int ntfs_file_read_block(struct page *page)
 			arr[nr++] = bh;
 			continue;
 		}
-		bh->b_dev = VFS_I(ni)->i_dev;
+		bh->b_bdev = vol->sb->s_bdev;
 		/* Is the block within the allowed limits? */
 		if (iblock < lblock) {
 			BOOL is_retry = FALSE;
@@ -437,7 +437,7 @@ static int ntfs_mftbmp_readpage(ntfs_volume *vol, struct page *page)
 			arr[nr++] = bh;
 			continue;
 		}
-		bh->b_dev = vol->mft_ino->i_dev;
+		bh->b_bdev = vol->sb->s_bdev;
 		/* Is the block within the allowed limits? */
 		if (iblock < lblock) {
 			/* Convert iblock into corresponding vcn and offset. */
@@ -681,7 +681,7 @@ int ntfs_mst_readpage(struct file *dir, struct page *page)
 			arr[nr++] = bh;
 			continue;
 		}
-		bh->b_dev = VFS_I(ni)->i_dev;
+		bh->b_bdev = vol->sb->s_bdev;
 		/* Is the block within the allowed limits? */
 		if (iblock < lblock) {
 			BOOL is_retry = FALSE;

fs/ntfs/compress.c

@@ -443,9 +443,9 @@ 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;
+	struct super_block *sb = vol->sb;
+	unsigned long block_size = sb->s_blocksize;
+	unsigned char block_size_bits = sb->s_blocksize_bits;
 	u8 *cb, *cb_pos, *cb_end;
 	struct buffer_head **bhs;
 	unsigned long offset, index = page->index;
@@ -575,8 +575,7 @@ int ntfs_file_read_compressed_block(struct page *page)
 		max_block = block + (vol->cluster_size >> block_size_bits);
 		do {
 			ntfs_debug("block = 0x%x.", block);
-			if (unlikely(!(bhs[nr_bhs] = getblk(dev, block,
-					block_size))))
+			if (unlikely(!(bhs[nr_bhs] = sb_getblk(sb, block))))
 				goto getblk_err;
 			nr_bhs++;
 		} while (++block < max_block);

fs/ntfs/super.c

@@ -25,8 +25,7 @@
 #include <linux/string.h>
 #include <linux/locks.h>
 #include <linux/spinlock.h>
-#include <linux/genhd.h>	/* For gendisk stuff. */
-#include <linux/blkdev.h>	/* Fox get_hardsect_size. */
+#include <linux/blkdev.h>	/* For bdev_hardsect_size(). */
 
 #include "ntfs.h"
 #include "sysctl.h"
@@ -1474,12 +1473,10 @@ struct super_operations ntfs_sops = {
  */
 static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
 {
-	extern int *blksize_size[];
 	ntfs_volume *vol;
 	struct buffer_head *bh;
 	struct inode *tmp_ino;
-	int old_blocksize, result;
-	kdev_t dev = sb->s_dev;
+	int result;
 
 	ntfs_debug("Entering.");
 	/* Allocate a new ntfs_volume and place it in sb->u.generic_sbp. */
@@ -1548,17 +1545,13 @@ static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
 	 * TODO: Fail safety check. In the future we should really be able to
 	 * cope with this being the case, but for now just bail out.
 	 */
-	if (get_hardsect_size(dev) > NTFS_BLOCK_SIZE) {
+	if (bdev_hardsect_size(sb->s_bdev) > NTFS_BLOCK_SIZE) {
 		if (!silent)
 			ntfs_error(sb, "Device has unsupported hardsect_size.");
 		goto err_out_now;
 	}
 
 	/* Setup the device access block size to NTFS_BLOCK_SIZE. */
-	if (!blksize_size[major(dev)])
-		old_blocksize = BLOCK_SIZE;
-	else
-		old_blocksize = blksize_size[major(dev)][minor(dev)];
 	if (sb_set_blocksize(sb, NTFS_BLOCK_SIZE) != NTFS_BLOCK_SIZE) {
 		if (!silent)
 			ntfs_error(sb, "Unable to set block size.");
@@ -1759,7 +1752,8 @@ static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
 	}
 set_blk_size_err_out_now:
 	/* Errors at this stage are irrelevant. */
-	sb_set_blocksize(sb, old_blocksize);
+	// FIXME: This should be done in fs/super.c::get_sb_bdev() itself! (AIA)
+	sb_set_blocksize(sb, sb->s_old_blocksize);
 err_out_now:
 	sb->u.generic_sbp = NULL;
 	kfree(vol);