This commit adds some statictics in extent status tree shrinker.  The
purpose to add these is that we want to collect more details when we
encounter a stall caused by extent status tree shrinker.  Here we count
the following statictics:
  stats:
    the number of all objects on all extent status trees
    the number of reclaimable objects on lru list
    cache hits/misses
    the last sorted interval
    the number of inodes on lru list
  average:
    scan time for shrinking some objects
    the number of shrunk objects
  maximum:
    the inode that has max nr. of objects on lru list
    the maximum scan time for shrinking some objects

The output looks like below:
  $ cat /proc/fs/ext4/sda1/es_shrinker_info
  stats:
    28228 objects
    6341 reclaimable objects
    5281/631 cache hits/misses
    586 ms last sorted interval
    250 inodes on lru list
  average:
    153 us scan time
    128 shrunk objects
  maximum:
    255 inode (255 objects, 198 reclaimable)
    125723 us max scan time

If the lru list has never been sorted, the following line will not be
printed:
    586ms last sorted interval
If there is an empty lru list, the following lines also will not be
printed:
    250 inodes on lru list
  ...
  maximum:
    255 inode (255 objects, 198 reclaimable)
    0 us max scan time

Meanwhile in this commit a new trace point is defined to print some
details in __ext4_es_shrink().

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

This commit improves the trace point of extents status tree.  We rename
trace_ext4_es_shrink_enter in ext4_es_count() because it is also used
in ext4_es_scan() and we can not identify them from the result.

Further this commit fixes a variable name in trace point in order to
keep consistency with others.

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

get_blocks is renamed to get_block.
Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Enable by default the block_validity feature, which checks for
collisions between newly allocated blocks and critical system
metadata.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

__wait_cp_io() is only called by jbd2_log_do_checkpoint().  Fold it in
to make it a bit easier to understand.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

__process_buffer() is only called by jbd2_log_do_checkpoint(), and it
had a very complex locking protocol where it would be called with the
j_list_lock, and sometimes exit with the lock held (if the return code
was 0), or release the lock.

This was confusing both to humans and to smatch (which erronously
complained that the lock was taken twice).

Folding __process_buffer() to the caller allows us to simplify the
control flow, making the resulting function easier to read and reason
about, and dropping the compiled size of fs/jbd2/checkpoint.c by 150
bytes (over 4% of the text size).
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

Make the function name less redundant.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Reuse the path object in ext4_move_extents() so we don't unnecessarily
free and reallocate it.

Also clean up the get_ext_path() wrapper so that it has the same
semantics of freeing the path object on error as ext4_ext_find_extent().
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Now that the semantics of ext4_ext_find_extent() are much cleaner,
it's safe and more efficient to reuse the path object across the
multiple calls to ext4_ext_find_extent() in ext4_ext_shift_extents().
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

This adds additional safety in case for some reason we end reusing a
path structure which isn't big enough for current depth of the inode.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Teach ext4_ext_drop_refs() to accept a NULL argument, much like
kfree().  This allows us to drop a lot of checks to make sure path is
non-NULL before calling ext4_ext_drop_refs().
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

In nearly all of the calls to ext4_ext_find_extent() where the caller
is trying to recycle the path object, ext4_ext_drop_refs() gets called
to release the buffer heads before the path object gets overwritten.
To simplify things for the callers, and to avoid the possibility of a
memory leak, make ext4_ext_find_extent() responsible for dropping the
buffers.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Drop EXT4_EX_NOFREE_ON_ERR from ext4_ext_create_new_leaf(),
ext4_split_extent(), ext4_convert_unwritten_extents_endio().

This requires fixing all of their callers to potentially
ext4_ext_find_extent() to free the struct ext4_ext_path object in case
of an error, and there are interlocking dependencies all the way up to
ext4_ext_map_blocks(), ext4_swap_extents(), and
ext4_ext_remove_space().

Once this is done, we can drop the EXT4_EX_NOFREE_ON_ERR flag since it
is no longer necessary.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Transfer responsibility of freeing struct ext4_ext_path on error to
ext4_ext_find_extent().
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

The function ext4_convert_initialized_extents() is only called by a
single function --- ext4_ext_convert_initalized_extents().  Inline the
code and get rid of the unnecessary bits in order to simplify the code.

Rename ext4_ext_convert_initalized_extents() to
convert_initalized_extents() since it's a static function that is
actually only used in a single caller, ext4_ext_map_blocks().
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Right now, there are a places where it is all to easy to leak memory
on an error path, via a usage like this:

	struct ext4_ext_path *path = NULL

	while (...) {
		...
		path = ext4_ext_find_extent(inode, block, path, 0);
		if (IS_ERR(path)) {
			/* oops, if path was non-NULL before the call to
			   ext4_ext_find_extent, we've leaked it!  :-(  */
			...
			return PTR_ERR(path);
		}
		...
	}

Unfortunately, there some code paths where we are doing the following
instead:

	path = ext4_ext_find_extent(inode, block, orig_path, 0);

and where it's important that we _not_ free orig_path in the case
where ext4_ext_find_extent() returns an error.

So change the function signature of ext4_ext_find_extent() so that it
takes a struct ext4_ext_path ** for its third argument, and by
default, on an error, it will free the struct ext4_ext_path, and then
zero out the struct ext4_ext_path * pointer.  In order to avoid
causing problems, we add a flag EXT4_EX_NOFREE_ON_ERR which causes
ext4_ext_find_extent() to use the original behavior of forcing the
caller to deal with freeing the original path pointer on the error
case.

The goal is to get rid of EXT4_EX_NOFREE_ON_ERR entirely, but this
allows for a gentle transition and makes the patches easier to verify.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

		

Commit b8a86845 introduced an accidental flag aliasing between
EXT4_EX_NOCACHE and EXT4_GET_BLOCKS_CONVERT_UNWRITTEN.

Fortunately, this didn't introduce any untorward side effects --- we
got lucky.  Nevertheless, fix this and leave a warning to hopefully
avoid this from happening in the future.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

We accidently aliased EXT4_EX_NOCACHE and EXT4_GET_CONVERT_UNWRITTEN
falgs, which apparently was hiding a bug that was unmasked when this
flag aliasing issue was addressed (see the subsequent commit).  The
reproduction case was:

   fsx -N 10000 -l 500000 -r 4096 -t 4096 -w 4096 -Z -R -W /vdb/junk

... which would cause fsx to report corruption in the data file.

The fix we have is a bit of an overkill, but I'd much rather be
conservative for now, and we can optimize ZERO_RANGE_FL handling
later.  The fact that we need to zap the extent_status cache for the
inode is unfortunate, but correctness is far more important than
performance.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>

If ext4_ext_find_extent() returns an error, we have to clear path1 or
path2 or else we would end up trying to free an ERR_PTR, which would
be bad.

Also eliminate some redundant code and mark the error paths as unlikely()
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

ext4_move_extents is too complex for review. It has duplicate almost
each function available in the rest of other codebase. It has useless
artificial restriction orig_offset == donor_offset. But in fact logic
of ext4_move_extents is very simple:

Iterate extents one by one (similar to ext4_fill_fiemap_extents)
   ->Iterate each page covered extent (similar to generic_perform_write)
     ->swap extents for covered by page (can be shared with IOC_MOVE_DATA)
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

This allows us to make mext_next_extent static and potentially get rid
of it.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

ext4_journal_get_write_access() has just been called in ext4_append()
calling it again here is duplicated.
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull ext4 bugfixes from Ted Ts'o:
 "Ext4 bug fixes for 3.17, to provide better handling of memory
  allocation failures, and to fix some journaling bugs involving
  journal checksums and FALLOC_FL_ZERO_RANGE"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix same-dir rename when inline data directory overflows
  jbd2: fix descriptor block size handling errors with journal_csum
  jbd2: fix infinite loop when recovering corrupt journal blocks
  ext4: update i_disksize coherently with block allocation on error path
  ext4: fix transaction issues for ext4_fallocate and ext_zero_range
  ext4: fix incorect journal credits reservation in ext4_zero_range
  ext4: move i_size,i_disksize update routines to helper function
  ext4: fix BUG_ON in mb_free_blocks()
  ext4: propagate errors up to ext4_find_entry()'s callers

Pull device mapper fix from Mike Snitzer:
 "Fix a 3.17-rc1 regression introduced by switching the DM crypt target
  to using per-bio data"

* tag 'dm-3.17-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm crypt: fix access beyond the end of allocated space

Pull block layer fixes from Jens Axboe:
 "A smaller collection of fixes that have come up since the initial
  merge window pull request.  This contains:

   - error handling cleanup and support for larger than 16 byte cdbs in
     sg_io() from Christoph.  The latter just matches what bsg and
     friends support, sg_io() got left out in the merge.

   - an option for brd to expose partitions in /proc/partitions.  They
     are hidden by default for compat reasons.  From Dmitry Monakhov.

   - a few blk-mq fixes from me - killing a dead/unused flag, fix for
     merging happening even if turned off, and correction of a few
     comments.

   - removal of unnecessary ->owner setting in systemace.  From Michal
     Simek.

   - two related fixes for a problem with nesting freezing of queues in
     blk-mq.  One from Ming Lei removing an unecessary freeze operation,
     and another from Tejun fixing the nesting regression introduced in
     the merge window.

   - fix for a BUG_ON() at bio_endio time when protection info is
     attached and the IO has an error.  From Sagi Grimberg.

   - two scsi_ioctl bug fixes for regressions with scsi-mq from Tony
     Battersby.

   - a cfq weight update fix and subsequent comment update from Toshiaki
     Makita"

* 'for-linus' of git://git.kernel.dk/linux-block:
  cfq-iosched: Add comments on update timing of weight
  cfq-iosched: Fix wrong children_weight calculation
  block: fix error handling in sg_io
  fix regression in SCSI_IOCTL_SEND_COMMAND
  scsi-mq: fix requests that use a separate CDB buffer
  block: support > 16 byte CDBs for SG_IO
  block: cleanup error handling in sg_io
  brd: add ram disk visibility option
  block: systemace: Remove .owner field for driver
  blk-mq: blk_mq_freeze_queue() should allow nesting
  blk-mq: correct a few wrong/bad comments
  block: Fix BUG_ON when pi errors occur
  blk-mq: don't allow merges if turned off for the queue
  blk-mq: get rid of unused BLK_MQ_F_SHOULD_SORT flag
  blk-mq: fix WARNING "percpu_ref_kill() called more than once!"

write{b,w,l,q}_relaxed are implemented by some architectures in order to
permit memory-mapped I/O writes with weaker barrier semantics than the
non-relaxed variants.

This patch implements these write macros for Alpha, in the same vein as
the relaxed read macros, which are already implemented.
Acked-by: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When performing a same-directory rename, it's possible that adding or
setting the new directory entry will cause the directory to overflow
the inline data area, which causes the directory to be converted to an
extent-based directory.  Under this circumstance it is necessary to
re-read the directory when deleting the old dirent because the "old
directory" context still points to i_block in the inode table, which
is now an extent tree root!  The delete fails with an FS error, and
the subsequent fsck complains about incorrect link counts and
hardlinked directories.

Test case (originally found with flat_dir_test in the metadata_csum
test program):

# mkfs.ext4 -O inline_data /dev/sda
# mount /dev/sda /mnt
# mkdir /mnt/x
# touch /mnt/x/changelog.gz /mnt/x/copyright /mnt/x/README.Debian
# sync
# for i in /mnt/x/*; do mv $i $i.longer; done
# ls -la /mnt/x/
total 0
-rw-r--r-- 1 root root 0 Aug 25 12:03 changelog.gz.longer
-rw-r--r-- 1 root root 0 Aug 25 12:03 copyright
-rw-r--r-- 1 root root 0 Aug 25 12:03 copyright.longer
-rw-r--r-- 1 root root 0 Aug 25 12:03 README.Debian.longer

(Hey!  Why are there four files now??)
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

It turns out that there are some serious problems with the on-disk
format of journal checksum v2.  The foremost is that the function to
calculate descriptor tag size returns sizes that are too big.  This
causes alignment issues on some architectures and is compounded by the
fact that some parts of jbd2 use the structure size (incorrectly) to
determine the presence of a 64bit journal instead of checking the
feature flags.

Therefore, introduce journal checksum v3, which enlarges the
descriptor block tag format to allow for full 32-bit checksums of
journal blocks, fix the journal tag function to return the correct
sizes, and fix the jbd2 recovery code to use feature flags to
determine 64bitness.

Add a few function helpers so we don't have to open-code quite so
many pieces.

Switching to a 16-byte block size was found to increase journal size
overhead by a maximum of 0.1%, to convert a 32-bit journal with no
checksumming to a 32-bit journal with checksum v3 enabled.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reported-by: TR Reardon <thomas_reardon@hotmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

When recovering the journal, don't fall into an infinite loop if we
encounter a corrupt journal block.  Instead, just skip the block and
return an error, which fails the mount and thus forces the user to run
a full filesystem fsck.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

In case of delalloc block i_disksize may be less than i_size. So we
have to update i_disksize each time we allocated and submitted some
blocks beyond i_disksize.  We weren't doing this on the error paths,
so fix this.

testcase: xfstest generic/019
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

The DM crypt target accesses memory beyond allocated space resulting in
a crash on 32 bit x86 systems.

This bug is very old (it dates back to 2.6.25 commit 3a7f6c99 "dm
crypt: use async crypto").  However, this bug was masked by the fact
that kmalloc rounds the size up to the next power of two.  This bug
wasn't exposed until 3.17-rc1 commit 298a9fa0 ("dm crypt: use per-bio
data").  By switching to using per-bio data there was no longer any
padding beyond the end of a dm-crypt allocated memory block.

To minimize allocation overhead dm-crypt puts several structures into one
block allocated with kmalloc.  The block holds struct ablkcipher_request,
cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))),
struct dm_crypt_request and an initialization vector.

The variable dmreq_start is set to offset of struct dm_crypt_request
within this memory block.  dm-crypt allocates the block with this size:
cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size.

When accessing the initialization vector, dm-crypt uses the function
iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq
+ 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1).

dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request
structure.  However, when dm-crypt accesses the initialization vector, it
takes a pointer to the end of dm_crypt_request, aligns it, and then uses
it as the initialization vector.  If the end of dm_crypt_request is not
aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the
alignment causes the initialization vector to point beyond the allocated
space.

Fix this bug by calculating the variable iv_size_padding and adding it
to the allocated size.

Also correct the alignment of dm_crypt_request.  struct dm_crypt_request
is specific to dm-crypt (it isn't used by the crypto subsystem at all),
so it is aligned on __alignof__(struct dm_crypt_request).

Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is
aligned as if the block was allocated with kmalloc.
Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Pull backlight fix from Lee Jones:
 "One simple fix to invalidate GPIO non-request"

* tag 'backlight-fixes-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  pwm-backlight: Fix bogus request for GPIO#0 when instantiated from DT

Pull mfd fixes from Lee Jones:
 "Couple of simple fixes due for the 3.17 rcs

  (and a sneaky document addition that slipped from the previous
  pull-request)"

* tag 'mfd-fixes-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd:
  mfd: twl4030-power: Fix PM idle pin configuration to not conflict with regulators
  mfd: tc3589x: Add device tree bindings
  mfd: ab8500-core: Use 'ifdef' for config options
  mfd: htc-i2cpld: Fix %d confusingly prefixed with 0x in format string
  mfd: omap-usb-host: Fix %d confusingly prefixed with 0x in format string