Commit Graph

465 Commits

Author SHA1 Message Date
Filipe Manana 7f042a8370 Btrfs: remove no longer used function extent_read_full_page_nolock()
Not needed after the previous patch named
"Btrfs: fix page reading in extent_same ioctl leading to csum errors".

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-02-03 19:27:10 +00:00
Chris Mason b28cf57246 Merge branch 'misc-cleanups-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2016-01-11 06:08:37 -08:00
Byongho Lee ee22184b53 Btrfs: use linux/sizes.h to represent constants
We use many constants to represent size and offset value.  And to make
code readable we use '256 * 1024 * 1024' instead of '268435456' to
represent '256MB'.  However we can make far more readable with 'SZ_256MB'
which is defined in the 'linux/sizes.h'.

So this patch replaces 'xxx * 1024 * 1024' kind of expression with
single 'SZ_xxxMB' if 'xxx' is a power of 2 then 'xxx * SZ_1M' if 'xxx' is
not a power of 2. And I haven't touched to '4096' & '8192' because it's
more intuitive than 'SZ_4KB' & 'SZ_8KB'.

Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 14:38:02 +01:00
Chris Mason f0f76413d3 Merge branch 'freespace-4.5' into for-linus-4.5 2015-12-23 13:29:09 -08:00
Chris Mason bb9d687618 Merge branch 'dev/simplify-set-bit' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-23 13:17:42 -08:00
Chris Mason f7d3d2f99e Merge branch 'freespace-tree' into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-18 11:11:10 -08:00
Omar Sandoval 0f3312295d Btrfs: add extent buffer bitmap sanity tests
Sanity test the extent buffer bitmap operations (test, set, and clear)
against the equivalent standard kernel operations.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
Omar Sandoval 3e1e8bb770 Btrfs: add extent buffer bitmap operations
These are going to be used for the free space tree bitmap items.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
David Sterba 35de6db28f btrfs: make set_range_writeback return void
Does not return any errors, nor anything from the callgraph. There's a
BUG_ON but it's a sanity check and not an error condition we could
recover from.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba f631157276 btrfs: make extent_range_redirty_for_io return void
Does not return any errors, nor anything from the callgraph. There's a
BUG_ON but it's a sanity check and not an error condition we could
recover from.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba bd1fa4f0b0 btrfs: make extent_range_clear_dirty_for_io return void
Does not return any errors, nor anything from the callgraph. There's a
BUG_ON but it's a sanity check and not an error condition we could
recover from.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba b5227c075b btrfs: make end_extent_writepage return void
Does not return any errors, nor anything from the callgraph.  The branch
in end_bio_extent_writepage has been skipped since
5fd0204355 ("Btrfs: finish ordered extents in their own thread").

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba a9d93e1778 btrfs: make extent_clear_unlock_delalloc return void
Does not return any errors, nor anything from the callgraph.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba 69ba39272c btrfs: make clear_extent_buffer_uptodate return void
Does not return any errors, nor anything from the callgraph.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba 09c25a8cda btrfs: make set_extent_buffer_uptodate return void
Does not return any errors, nor anything from the callgraph.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba cd716d8fea btrfs: make lock_extent static inline
One call less reduces stack usage, code slightly reduced as well.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:44:59 +01:00
David Sterba ff13db41f1 btrfs: drop unused parameter from lock_extent_bits
We've always passed 0. Stack usage will slightly decrease.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:30:40 +01:00
David Sterba e83b1d91f8 btrfs: make clear_extent_bit helpers static inline
The funcions just wrap the clear_extent_bit API and generate function
calls. This increases stack consumption and may negatively affect
performance due to icache misses. We can simply make the helpers static
inline and keep the type checking and API untouched. The code slightly
decreases:

   text	   data	    bss	    dec	    hex	filename
 938667	  43670	  23144	1005481	  f57a9	fs/btrfs/btrfs.ko.before
 939651	  43670	  23144	1006465	  f5b81	fs/btrfs/btrfs.ko.after

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:17:30 +01:00
David Sterba c63179556a btrfs: make set_extent_bit helpers static inline
The funcions just wrap the set_extent_bit API and generate function
calls. This increases stack consumption and may negatively affect
performance due to icache misses. We can simply make the helpers static
inline and keep the type checking and API untouched. The code slightly
increases:

   text	   data	    bss	    dec	    hex	filename
 938427	  43670	  23144	1005241	  f56b9	fs/btrfs/btrfs.ko.before
 938667	  43670	  23144	1005481	  f57a9	fs/btrfs/btrfs.ko

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:08:11 +01:00
Linus Torvalds ad804a0b2a Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:

 - most of the rest of MM

 - procfs

 - lib/ updates

 - printk updates

 - bitops infrastructure tweaks

 - checkpatch updates

 - nilfs2 update

 - signals

 - various other misc bits: coredump, seqfile, kexec, pidns, zlib, ipc,
   dma-debug, dma-mapping, ...

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (102 commits)
  ipc,msg: drop dst nil validation in copy_msg
  include/linux/zutil.h: fix usage example of zlib_adler32()
  panic: release stale console lock to always get the logbuf printed out
  dma-debug: check nents in dma_sync_sg*
  dma-mapping: tidy up dma_parms default handling
  pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode
  kexec: use file name as the output message prefix
  fs, seqfile: always allow oom killer
  seq_file: reuse string_escape_str()
  fs/seq_file: use seq_* helpers in seq_hex_dump()
  coredump: change zap_threads() and zap_process() to use for_each_thread()
  coredump: ensure all coredumping tasks have SIGNAL_GROUP_COREDUMP
  signal: remove jffs2_garbage_collect_thread()->allow_signal(SIGCONT)
  signal: introduce kernel_signal_stop() to fix jffs2_garbage_collect_thread()
  signal: turn dequeue_signal_lock() into kernel_dequeue_signal()
  signals: kill block_all_signals() and unblock_all_signals()
  nilfs2: fix gcc uninitialized-variable warnings in powerpc build
  nilfs2: fix gcc unused-but-set-variable warnings
  MAINTAINERS: nilfs2: add header file for tracing
  nilfs2: add tracepoints for analyzing reading and writing metadata files
  ...
2015-11-07 14:32:45 -08:00
Mel Gorman d0164adc89 mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Qu Wenruo fefdc55702 btrfs: extent_io: Introduce new function clear_record_extent_bits()
Introduce new function clear_record_extent_bits(), which will clear bits
for given range and record the details about which ranges are cleared
and how many bytes in total it changes.

This provides the basis for later qgroup reserve codes.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-21 18:37:44 -07:00
Qu Wenruo d38ed27f04 btrfs: extent_io: Introduce new function set_record_extent_bits
Introduce new function set_record_extent_bits(), which will not only set
given bits, but also record how many bytes are changed, and detailed
range info.

This is quite important for later qgroup reserve framework.
The number of bytes will be used to do qgroup reserve, and detailed
range info will be used to cleanup for EQUOT case.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-21 18:37:44 -07:00
Filipe Manana 5e6ecb362b Btrfs: fix double range unlock of hole region when reading page
If when reading a page we find a hole and our caller had already locked
the range (bio flags has the bit EXTENT_BIO_PARENT_LOCKED set), we end
up unlocking the hole's range and then later our caller unlocks it
again, which might have already been locked by some other task once
the first unlock happened.

Currently this can only happen during a call to the extent_same ioctl,
as it's the only caller of __do_readpage() that sets the bit
EXTENT_BIO_PARENT_LOCKED for bio flags.

Fix this by leaving the unlock exclusively to the caller.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-14 04:37:00 +01:00
Chris Mason 640926ffdd Merge branch 'cleanup/messages' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-12 16:22:26 -07:00
Linus Torvalds 175d58cfed Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "These are small and assorted.  Neil's is the oldest, I dropped the
  ball thinking he was going to send it in"

* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: support NFSv2 export
  Btrfs: open_ctree: Fix possible memory leak
  Btrfs: fix deadlock when finalizing block group creation
  Btrfs: update fix for read corruption of compressed and shared extents
  Btrfs: send, fix corner case for reference overwrite detection
2015-10-09 16:39:35 -07:00
David Sterba f14d104dbd btrfs: switch more printks to our helpers
Convert the simple cases, not all functions provide a way to reach the
fs_info. Also skipped debugging messages (print-tree, integrity
checker and pr_debug) and messages that are printed from possibly
unfinished mount.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08 13:08:03 +02:00
David Sterba 9464732266 btrfs: switch message printers to ratelimited variants
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08 13:04:06 +02:00
David Sterba b14af3b46f btrfs: switch message printers to ratelimited _in_rcu variants
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08 11:07:55 +02:00
Filipe Manana 808f80b467 Btrfs: update fix for read corruption of compressed and shared extents
My previous fix in commit 005efedf2c ("Btrfs: fix read corruption of
compressed and shared extents") was effective only if the compressed
extents cover a file range with a length that is not a multiple of 16
pages. That's because the detection of when we reached a different range
of the file that shares the same compressed extent as the previously
processed range was done at extent_io.c:__do_contiguous_readpages(),
which covers subranges with a length up to 16 pages, because
extent_readpages() groups the pages in clusters no larger than 16 pages.
So fix this by tracking the start of the previously processed file
range's extent map at extent_readpages().

The following test case for fstests reproduces the issue:

  seq=`basename $0`
  seqres=$RESULT_DIR/$seq
  echo "QA output created by $seq"
  tmp=/tmp/$$
  status=1	# failure is the default!
  trap "_cleanup; exit \$status" 0 1 2 3 15

  _cleanup()
  {
      rm -f $tmp.*
  }

  # get standard environment, filters and checks
  . ./common/rc
  . ./common/filter

  # real QA test starts here
  _need_to_be_root
  _supported_fs btrfs
  _supported_os Linux
  _require_scratch
  _require_cloner

  rm -f $seqres.full

  test_clone_and_read_compressed_extent()
  {
      local mount_opts=$1

      _scratch_mkfs >>$seqres.full 2>&1
      _scratch_mount $mount_opts

      # Create our test file with a single extent of 64Kb that is going to
      # be compressed no matter which compression algo is used (zlib/lzo).
      $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 64K" \
          $SCRATCH_MNT/foo | _filter_xfs_io

      # Now clone the compressed extent into an adjacent file offset.
      $CLONER_PROG -s 0 -d $((64 * 1024)) -l $((64 * 1024)) \
          $SCRATCH_MNT/foo $SCRATCH_MNT/foo

      echo "File digest before unmount:"
      md5sum $SCRATCH_MNT/foo | _filter_scratch

      # Remount the fs or clear the page cache to trigger the bug in
      # btrfs. Because the extent has an uncompressed length that is a
      # multiple of 16 pages, all the pages belonging to the second range
      # of the file (64K to 128K), which points to the same extent as the
      # first range (0K to 64K), had their contents full of zeroes instead
      # of the byte 0xaa. This was a bug exclusively in the read path of
      # compressed extents, the correct data was stored on disk, btrfs
      # just failed to fill in the pages correctly.
      _scratch_remount

      echo "File digest after remount:"
      # Must match the digest we got before.
      md5sum $SCRATCH_MNT/foo | _filter_scratch
  }

  echo -e "\nTesting with zlib compression..."
  test_clone_and_read_compressed_extent "-o compress=zlib"

  _scratch_unmount

  echo -e "\nTesting with lzo compression..."
  test_clone_and_read_compressed_extent "-o compress=lzo"

  status=0
  exit

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Timofey Titovets <nefelim4ag@gmail.com>
2015-10-05 16:56:27 -07:00
Linus Torvalds 03e8f64486 Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This is an assorted set I've been queuing up:

  Jeff Mahoney tracked down a tricky one where we ended up starting IO
  on the wrong mapping for special files in btrfs_evict_inode.  A few
  people reported this one on the list.

  Filipe found (and provided a test for) a difficult bug in reading
  compressed extents, and Josef fixed up some quota record keeping with
  snapshot deletion.  Chandan killed off an accounting bug during DIO
  that lead to WARN_ONs as we freed inodes"

* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: keep dropped roots in cache until transaction commit
  Btrfs: Direct I/O: Fix space accounting
  btrfs: skip waiting on ordered range for special files
  Btrfs: fix read corruption of compressed and shared extents
  Btrfs: remove unnecessary locking of cleaner_mutex to avoid deadlock
  Btrfs: don't initialize a space info as full to prevent ENOSPC
2015-09-25 12:08:41 -07:00
Filipe Manana 005efedf2c Btrfs: fix read corruption of compressed and shared extents
If a file has a range pointing to a compressed extent, followed by
another range that points to the same compressed extent and a read
operation attempts to read both ranges (either completely or part of
them), the pages that correspond to the second range are incorrectly
filled with zeroes.

Consider the following example:

  File layout
  [0 - 8K]                      [8K - 24K]
      |                             |
      |                             |
   points to extent X,         points to extent X,
   offset 4K, length of 8K     offset 0, length 16K

  [extent X, compressed length = 4K uncompressed length = 16K]

If a readpages() call spans the 2 ranges, a single bio to read the extent
is submitted - extent_io.c:submit_extent_page() would only create a new
bio to cover the second range pointing to the extent if the extent it
points to had a different logical address than the extent associated with
the first range. This has a consequence of the compressed read end io
handler (compression.c:end_compressed_bio_read()) finish once the extent
is decompressed into the pages covering the first range, leaving the
remaining pages (belonging to the second range) filled with zeroes (done
by compression.c:btrfs_clear_biovec_end()).

So fix this by submitting the current bio whenever we find a range
pointing to a compressed extent that was preceded by a range with a
different extent map. This is the simplest solution for this corner
case. Making the end io callback populate both ranges (or more, if we
have multiple pointing to the same extent) is a much more complex
solution since each bio is tightly coupled with a single extent map and
the extent maps associated to the ranges pointing to the shared extent
can have different offsets and lengths.

The following test case for fstests triggers the issue:

  seq=`basename $0`
  seqres=$RESULT_DIR/$seq
  echo "QA output created by $seq"
  tmp=/tmp/$$
  status=1	# failure is the default!
  trap "_cleanup; exit \$status" 0 1 2 3 15

  _cleanup()
  {
      rm -f $tmp.*
  }

  # get standard environment, filters and checks
  . ./common/rc
  . ./common/filter

  # real QA test starts here
  _need_to_be_root
  _supported_fs btrfs
  _supported_os Linux
  _require_scratch
  _require_cloner

  rm -f $seqres.full

  test_clone_and_read_compressed_extent()
  {
      local mount_opts=$1

      _scratch_mkfs >>$seqres.full 2>&1
      _scratch_mount $mount_opts

      # Create a test file with a single extent that is compressed (the
      # data we write into it is highly compressible no matter which
      # compression algorithm is used, zlib or lzo).
      $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 4K"        \
                      -c "pwrite -S 0xbb 4K 8K"        \
                      -c "pwrite -S 0xcc 12K 4K"       \
                      $SCRATCH_MNT/foo | _filter_xfs_io

      # Now clone our extent into an adjacent offset.
      $CLONER_PROG -s $((4 * 1024)) -d $((16 * 1024)) -l $((8 * 1024)) \
          $SCRATCH_MNT/foo $SCRATCH_MNT/foo

      # Same as before but for this file we clone the extent into a lower
      # file offset.
      $XFS_IO_PROG -f -c "pwrite -S 0xaa 8K 4K"         \
                      -c "pwrite -S 0xbb 12K 8K"        \
                      -c "pwrite -S 0xcc 20K 4K"        \
                      $SCRATCH_MNT/bar | _filter_xfs_io

      $CLONER_PROG -s $((12 * 1024)) -d 0 -l $((8 * 1024)) \
          $SCRATCH_MNT/bar $SCRATCH_MNT/bar

      echo "File digests before unmounting filesystem:"
      md5sum $SCRATCH_MNT/foo | _filter_scratch
      md5sum $SCRATCH_MNT/bar | _filter_scratch

      # Evicting the inode or clearing the page cache before reading
      # again the file would also trigger the bug - reads were returning
      # all bytes in the range corresponding to the second reference to
      # the extent with a value of 0, but the correct data was persisted
      # (it was a bug exclusively in the read path). The issue happened
      # only if the same readpages() call targeted pages belonging to the
      # first and second ranges that point to the same compressed extent.
      _scratch_remount

      echo "File digests after mounting filesystem again:"
      # Must match the same digests we got before.
      md5sum $SCRATCH_MNT/foo | _filter_scratch
      md5sum $SCRATCH_MNT/bar | _filter_scratch
  }

  echo -e "\nTesting with zlib compression..."
  test_clone_and_read_compressed_extent "-o compress=zlib"

  _scratch_unmount

  echo -e "\nTesting with lzo compression..."
  test_clone_and_read_compressed_extent "-o compress=lzo"

  status=0
  exit

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo<quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2015-09-15 00:59:31 +01:00
Linus Torvalds 22365979ab Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This has Jeff Mahoney's long standing trim patch that fixes corners
  where trims were missing.  Omar has some raid5/6 fixes, especially for
  using scrub and device replace when devices are missing.

  Zhao Lie continues cleaning and fixing things, this series fixes some
  really hard to hit corners in xfstests.  I had to pull it last merge
  window due to some deadlocks, but those are now resolved.

  I added support for Tejun's new blkio controllers.  It seems to work
  well for single devices, we'll expand to multi-device as well"

* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (47 commits)
  btrfs: fix compile when block cgroups are not enabled
  Btrfs: fix file read corruption after extent cloning and fsync
  Btrfs: check if previous transaction aborted to avoid fs corruption
  btrfs: use __GFP_NOFAIL in alloc_btrfs_bio
  btrfs: Prevent from early transaction abort
  btrfs: Remove unused arguments in tree-log.c
  btrfs: Remove useless condition in start_log_trans()
  Btrfs: add support for blkio controllers
  Btrfs: remove unused mutex from struct 'btrfs_fs_info'
  Btrfs: fix parity scrub of RAID 5/6 with missing device
  Btrfs: fix device replace of a missing RAID 5/6 device
  Btrfs: add RAID 5/6 BTRFS_RBIO_REBUILD_MISSING operation
  Btrfs: count devices correctly in readahead during RAID 5/6 replace
  Btrfs: remove misleading handling of missing device scrub
  btrfs: fix clone / extent-same deadlocks
  Btrfs: fix defrag to merge tail file extent
  Btrfs: fix warning in backref walking
  btrfs: Add WARN_ON() for double lock in btrfs_tree_lock()
  btrfs: Remove root argument in extent_data_ref_count()
  btrfs: Fix wrong comment of btrfs_alloc_tree_block()
  ...
2015-09-05 15:14:43 -07:00
Chris Mason 3a9508b022 btrfs: fix compile when block cgroups are not enabled
bio->bi_css and bio->bi_ioc don't exist when block cgroups are not on.
This adds an ifdef around them.  It's not perfect, but our
use of bi_ioc is being removed in the 4.3 merge window.

The bi_css usage really should go into bio_clone, but I want to make
sure that doesn't introduce problems for other bio_clone use cases.

Signed-off-by: Chris Mason <clm@fb.com>
2015-08-21 10:08:13 -07:00
Michal Hocko d1b5c5671d btrfs: Prevent from early transaction abort
Btrfs relies on GFP_NOFS allocation when committing the transaction but
this allocation context is rather weak wrt. reclaim capabilities. The
page allocator currently tries hard to not fail these allocations if
they are small (<=PAGE_ALLOC_COSTLY_ORDER) so this is not a problem
currently but there is an attempt to move away from the default no-fail
behavior and allow these allocation to fail more eagerly. And this would
lead to a pre-mature transaction abort as follows:

[   55.328093] Call Trace:
[   55.328890]  [<ffffffff8154e6f0>] dump_stack+0x4f/0x7b
[   55.330518]  [<ffffffff8108fa28>] ? console_unlock+0x334/0x363
[   55.332738]  [<ffffffff8110873e>] __alloc_pages_nodemask+0x81d/0x8d4
[   55.334910]  [<ffffffff81100752>] pagecache_get_page+0x10e/0x20c
[   55.336844]  [<ffffffffa007d916>] alloc_extent_buffer+0xd0/0x350 [btrfs]
[   55.338973]  [<ffffffffa0059d8c>] btrfs_find_create_tree_block+0x15/0x17 [btrfs]
[   55.341329]  [<ffffffffa004f728>] btrfs_alloc_tree_block+0x18c/0x405 [btrfs]
[   55.343566]  [<ffffffffa003fa34>] split_leaf+0x1e4/0x6a6 [btrfs]
[   55.345577]  [<ffffffffa0040567>] btrfs_search_slot+0x671/0x831 [btrfs]
[   55.347679]  [<ffffffff810682d7>] ? get_parent_ip+0xe/0x3e
[   55.349434]  [<ffffffffa0041cb2>] btrfs_insert_empty_items+0x5d/0xa8 [btrfs]
[   55.351681]  [<ffffffffa004ecfb>] __btrfs_run_delayed_refs+0x7a6/0xf35 [btrfs]
[   55.353979]  [<ffffffffa00512ea>] btrfs_run_delayed_refs+0x6e/0x226 [btrfs]
[   55.356212]  [<ffffffffa0060e21>] ? start_transaction+0x192/0x534 [btrfs]
[   55.358378]  [<ffffffffa0060e21>] ? start_transaction+0x192/0x534 [btrfs]
[   55.360626]  [<ffffffffa0060221>] btrfs_commit_transaction+0x4c/0xaba [btrfs]
[   55.362894]  [<ffffffffa0060e21>] ? start_transaction+0x192/0x534 [btrfs]
[   55.365221]  [<ffffffffa0073428>] btrfs_sync_file+0x29c/0x310 [btrfs]
[   55.367273]  [<ffffffff81186808>] vfs_fsync_range+0x8f/0x9e
[   55.369047]  [<ffffffff81186833>] vfs_fsync+0x1c/0x1e
[   55.370654]  [<ffffffff81186869>] do_fsync+0x34/0x4e
[   55.372246]  [<ffffffff81186ab3>] SyS_fsync+0x10/0x14
[   55.373851]  [<ffffffff81554f97>] system_call_fastpath+0x12/0x6f
[   55.381070] BTRFS: error (device hdb1) in btrfs_run_delayed_refs:2821: errno=-12 Out of memory
[   55.382431] BTRFS warning (device hdb1): Skipping commit of aborted transaction.
[   55.382433] BTRFS warning (device hdb1): cleanup_transaction:1692: Aborting unused transaction(IO failure).
[   55.384280] ------------[ cut here ]------------
[   55.384312] WARNING: CPU: 0 PID: 3010 at fs/btrfs/delayed-ref.c:438 btrfs_select_ref_head+0xd9/0xfe [btrfs]()
[...]
[   55.384337] Call Trace:
[   55.384353]  [<ffffffff8154e6f0>] dump_stack+0x4f/0x7b
[   55.384357]  [<ffffffff8107f717>] ? down_trylock+0x2d/0x37
[   55.384359]  [<ffffffff81046977>] warn_slowpath_common+0xa1/0xbb
[   55.384398]  [<ffffffffa00a1d6b>] ? btrfs_select_ref_head+0xd9/0xfe [btrfs]
[   55.384400]  [<ffffffff81046a34>] warn_slowpath_null+0x1a/0x1c
[   55.384423]  [<ffffffffa00a1d6b>] btrfs_select_ref_head+0xd9/0xfe [btrfs]
[   55.384446]  [<ffffffffa004e5f7>] ? __btrfs_run_delayed_refs+0xa2/0xf35 [btrfs]
[   55.384455]  [<ffffffffa004e600>] __btrfs_run_delayed_refs+0xab/0xf35 [btrfs]
[   55.384476]  [<ffffffffa00512ea>] btrfs_run_delayed_refs+0x6e/0x226 [btrfs]
[   55.384499]  [<ffffffffa0060e21>] ? start_transaction+0x192/0x534 [btrfs]
[   55.384521]  [<ffffffffa0060e21>] ? start_transaction+0x192/0x534 [btrfs]
[   55.384543]  [<ffffffffa0060221>] btrfs_commit_transaction+0x4c/0xaba [btrfs]
[   55.384565]  [<ffffffffa0060e21>] ? start_transaction+0x192/0x534 [btrfs]
[   55.384588]  [<ffffffffa0073428>] btrfs_sync_file+0x29c/0x310 [btrfs]
[   55.384591]  [<ffffffff81186808>] vfs_fsync_range+0x8f/0x9e
[   55.384592]  [<ffffffff81186833>] vfs_fsync+0x1c/0x1e
[   55.384593]  [<ffffffff81186869>] do_fsync+0x34/0x4e
[   55.384594]  [<ffffffff81186ab3>] SyS_fsync+0x10/0x14
[   55.384595]  [<ffffffff81554f97>] system_call_fastpath+0x12/0x6f
[...]
[   55.384608] ---[ end trace c29799da1d4dd621 ]---
[   55.437323] BTRFS info (device hdb1): forced readonly
[   55.438815] BTRFS info (device hdb1): delayed_refs has NO entry

Fix this by being explicit about the no-fail behavior of this allocation
path and use __GFP_NOFAIL.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-08-19 14:25:15 -07:00
Kent Overstreet b54ffb73ca block: remove bio_get_nr_vecs()
We can always fill up the bio now, no need to estimate the possible
size based on queue parameters.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[hch: rebased and wrote a changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-13 12:32:04 -06:00
Chris Mason da2f0f74cf Btrfs: add support for blkio controllers
This attaches accounting information to bios as we submit them so the
new blkio controllers can throttle on btrfs filesystems.

Not much is required, we're just associating bios with blkcgs during clone,
calling wbc_init_bio()/wbc_account_io() during writepages submission,
and attaching the bios to the current context during direct IO.

Finally if we are splitting bios during btrfs_map_bio, this attaches
accounting information to the split.

The end result is able to throttle nicely on single disk filesystems.  A
little more work is required for multi-device filesystems.

Signed-off-by: Chris Mason <clm@fb.com>
2015-08-09 07:35:06 -07:00
Christoph Hellwig 4246a0b63b block: add a bi_error field to struct bio
Currently we have two different ways to signal an I/O error on a BIO:

 (1) by clearing the BIO_UPTODATE flag
 (2) by returning a Linux errno value to the bi_end_io callback

The first one has the drawback of only communicating a single possible
error (-EIO), and the second one has the drawback of not beeing persistent
when bios are queued up, and are not passed along from child to parent
bio in the ever more popular chaining scenario.  Having both mechanisms
available has the additional drawback of utterly confusing driver authors
and introducing bugs where various I/O submitters only deal with one of
them, and the others have to add boilerplate code to deal with both kinds
of error returns.

So add a new bi_error field to store an errno value directly in struct
bio and remove the existing mechanisms to clean all this up.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-29 08:55:15 -06:00
Linus Torvalds 043cd04950 Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "Outside of our usual batch of fixes, this integrates the subvolume
  quota updates that Qu Wenruo from Fujitsu has been working on for a
  few releases now.  He gets an extra gold star for making btrfs smaller
  this time, and fixing a number of quota corners in the process.

  Dave Sterba tested and integrated Anand Jain's sysfs improvements.
  Outside of exporting a symbol (ack'd by Greg) these are all internal
  to btrfs and it's mostly cleanups and fixes.  Anand also attached some
  of our sysfs objects to our internal device management structs instead
  of an object off the super block.  It will make device management
  easier overall and it's a better fit for how the sysfs files are used.
  None of the existing sysfs files are moved around.

  Thanks for all the fixes everyone"

* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (87 commits)
  btrfs: delayed-ref: double free in btrfs_add_delayed_tree_ref()
  Btrfs: Check if kobject is initialized before put
  lib: export symbol kobject_move()
  Btrfs: sysfs: add support to show replacing target in the sysfs
  Btrfs: free the stale device
  Btrfs: use received_uuid of parent during send
  Btrfs: fix use-after-free in btrfs_replay_log
  btrfs: wait for delayed iputs on no space
  btrfs: qgroup: Make snapshot accounting work with new extent-oriented qgroup.
  btrfs: qgroup: Add the ability to skip given qgroup for old/new_roots.
  btrfs: ulist: Add ulist_del() function.
  btrfs: qgroup: Cleanup the old ref_node-oriented mechanism.
  btrfs: qgroup: Switch self test to extent-oriented qgroup mechanism.
  btrfs: qgroup: Switch to new extent-oriented qgroup mechanism.
  btrfs: qgroup: Switch rescan to new mechanism.
  btrfs: qgroup: Add new qgroup calculation function btrfs_qgroup_account_extents().
  btrfs: backref: Add special time_seq == (u64)-1 case for btrfs_find_all_roots().
  btrfs: qgroup: Add new function to record old_roots.
  btrfs: qgroup: Record possible quota-related extent for qgroup.
  btrfs: qgroup: Add function qgroup_update_counters().
  ...
2015-06-30 20:07:45 -07:00
Linus Torvalds bfffa1cc9d Merge branch 'for-4.2/core' of git://git.kernel.dk/linux-block
Pull core block IO update from Jens Axboe:
 "Nothing really major in here, mostly a collection of smaller
  optimizations and cleanups, mixed with various fixes.  In more detail,
  this contains:

   - Addition of policy specific data to blkcg for block cgroups.  From
     Arianna Avanzini.

   - Various cleanups around command types from Christoph.

   - Cleanup of the suspend block I/O path from Christoph.

   - Plugging updates from Shaohua and Jeff Moyer, for blk-mq.

   - Eliminating atomic inc/dec of both remaining IO count and reference
     count in a bio.  From me.

   - Fixes for SG gap and chunk size support for data-less (discards)
     IO, so we can merge these better.  From me.

   - Small restructuring of blk-mq shared tag support, freeing drivers
     from iterating hardware queues.  From Keith Busch.

   - A few cfq-iosched tweaks, from Tahsin Erdogan and me.  Makes the
     IOPS mode the default for non-rotational storage"

* 'for-4.2/core' of git://git.kernel.dk/linux-block: (35 commits)
  cfq-iosched: fix other locations where blkcg_to_cfqgd() can return NULL
  cfq-iosched: fix sysfs oops when attempting to read unconfigured weights
  cfq-iosched: move group scheduling functions under ifdef
  cfq-iosched: fix the setting of IOPS mode on SSDs
  blktrace: Add blktrace.c to BLOCK LAYER in MAINTAINERS file
  block, cgroup: implement policy-specific per-blkcg data
  block: Make CFQ default to IOPS mode on SSDs
  block: add blk_set_queue_dying() to blkdev.h
  blk-mq: Shared tag enhancements
  block: don't honor chunk sizes for data-less IO
  block: only honor SG gap prevention for merges that contain data
  block: fix returnvar.cocci warnings
  block, dm: don't copy bios for request clones
  block: remove management of bi_remaining when restoring original bi_end_io
  block: replace trylock with mutex_lock in blkdev_reread_part()
  block: export blkdev_reread_part() and __blkdev_reread_part()
  suspend: simplify block I/O handling
  block: collapse bio bit space
  block: remove unused BIO_RW_BLOCK and BIO_EOF flags
  block: remove BIO_EOPNOTSUPP
  ...
2015-06-25 14:29:53 -07:00
Josef Bacik 0d2b2372e0 Btrfs: set UNWRITTEN for prealloc'ed extents in fiemap
We should be doing this, it's weird we hadn't been doing this.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:03 -07:00
Filipe Manana 0f31871f44 Btrfs: wake up extent state waiters on unlock through clear_extent_bits
When we clear an extent state's EXTENT_LOCKED bit with clear_extent_bits()
through free_io_failure(), we weren't waking up any tasks waiting for the
extent's state EXTENT_LOCKED bit, leading to an hang.

So make sure clear_extent_bits() ends up waking up any waiters if the
bit EXTENT_LOCKED is supplied by its callers.

Zygo Blaxell was experiencing such hangs at inode eviction time after
file unlinks. Thanks to him for a set of scripts to reproduce the issue.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:02:56 -07:00
Christoph Hellwig b25de9d6da block: remove BIO_EOPNOTSUPP
Since the big barrier rewrite/removal in 2007 we never fail FLUSH or
FUA requests, which means we can remove the magic BIO_EOPNOTSUPP flag
to help propagating those to the buffer_head layer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-19 09:17:03 -06:00
Filipe Manana 062c19e9dd Btrfs: fix race when reusing stale extent buffers that leads to BUG_ON
There's a race between releasing extent buffers that are flagged as stale
and recycling them that makes us it the following BUG_ON at
btrfs_release_extent_buffer_page:

    BUG_ON(extent_buffer_under_io(eb))

The BUG_ON is triggered because the extent buffer has the flag
EXTENT_BUFFER_DIRTY set as a consequence of having been reused and made
dirty by another concurrent task.

Here follows a sequence of steps that leads to the BUG_ON.

      CPU 0                                                    CPU 1                                                CPU 2

path->nodes[0] == eb X
X->refs == 2 (1 for the tree, 1 for the path)
btrfs_header_generation(X) == current trans id
flag EXTENT_BUFFER_DIRTY set on X

btrfs_release_path(path)
    unlocks X

                                                      reads eb X
                                                         X->refs incremented to 3
                                                      locks eb X
                                                      btrfs_del_items(X)
                                                         X becomes empty
                                                         clean_tree_block(X)
                                                             clear EXTENT_BUFFER_DIRTY from X
                                                         btrfs_del_leaf(X)
                                                             unlocks X
                                                             extent_buffer_get(X)
                                                                X->refs incremented to 4
                                                             btrfs_free_tree_block(X)
                                                                X's range is not pinned
                                                                X's range added to free
                                                                  space cache
                                                             free_extent_buffer_stale(X)
                                                                lock X->refs_lock
                                                                set EXTENT_BUFFER_STALE on X
                                                                release_extent_buffer(X)
                                                                    X->refs decremented to 3
                                                                    unlocks X->refs_lock
                                                      btrfs_release_path()
                                                         unlocks X
                                                         free_extent_buffer(X)
                                                             X->refs becomes 2

                                                                                                      __btrfs_cow_block(Y)
                                                                                                          btrfs_alloc_tree_block()
                                                                                                              btrfs_reserve_extent()
                                                                                                                  find_free_extent()
                                                                                                                      gets offset == X->start
                                                                                                              btrfs_init_new_buffer(X->start)
                                                                                                                  btrfs_find_create_tree_block(X->start)
                                                                                                                      alloc_extent_buffer(X->start)
                                                                                                                          find_extent_buffer(X->start)
                                                                                                                              finds eb X in radix tree

    free_extent_buffer(X)
        lock X->refs_lock
            test X->refs == 2
            test bit EXTENT_BUFFER_STALE is set
            test !extent_buffer_under_io(eb)

                                                                                                                              increments X->refs to 3
                                                                                                                              mark_extent_buffer_accessed(X)
                                                                                                                                  check_buffer_tree_ref(X)
                                                                                                                                    --> does nothing,
                                                                                                                                        X->refs >= 2 and
                                                                                                                                        EXTENT_BUFFER_TREE_REF
                                                                                                                                        is set in X
                                                                                                              clear EXTENT_BUFFER_STALE from X
                                                                                                              locks X
                                                                                                          btrfs_mark_buffer_dirty()
                                                                                                              set_extent_buffer_dirty(X)
                                                                                                                  check_buffer_tree_ref(X)
                                                                                                                     --> does nothing, X->refs >= 2 and
                                                                                                                         EXTENT_BUFFER_TREE_REF is set
                                                                                                                  sets EXTENT_BUFFER_DIRTY on X

            test and clear EXTENT_BUFFER_TREE_REF
            decrements X->refs to 2
        release_extent_buffer(X)
            decrements X->refs to 1
            unlock X->refs_lock

                                                                                                      unlock X
                                                                                                      free_extent_buffer(X)
                                                                                                          lock X->refs_lock
                                                                                                          release_extent_buffer(X)
                                                                                                              decrements X->refs to 0
                                                                                                              btrfs_release_extent_buffer_page(X)
                                                                                                                   BUG_ON(extent_buffer_under_io(X))
                                                                                                                       --> EXTENT_BUFFER_DIRTY set on X

Fix this by making find_extent buffer wait for any ongoing task currently
executing free_extent_buffer()/free_extent_buffer_stale() if the extent
buffer has the stale flag set.
A more clean alternative would be to always increment the extent buffer's
reference count while holding its refs_lock spinlock but find_extent_buffer
is a performance critical area and that would cause lock contention whenever
multiple tasks search for the same extent buffer concurrently.

A build server running a SLES 12 kernel (3.12 kernel + over 450 upstream
btrfs patches backported from newer kernels) was hitting this often:

[1212302.461948] kernel BUG at ../fs/btrfs/extent_io.c:4507!
(...)
[1212302.470219] CPU: 1 PID: 19259 Comm: bs_sched Not tainted 3.12.36-38-default #1
[1212302.540792] Hardware name: Supermicro PDSM4/PDSM4, BIOS 6.00 04/17/2006
[1212302.540792] task: ffff8800e07e0100 ti: ffff8800d6412000 task.ti: ffff8800d6412000
[1212302.540792] RIP: 0010:[<ffffffffa0507081>]  [<ffffffffa0507081>] btrfs_release_extent_buffer_page.constprop.51+0x101/0x110 [btrfs]
(...)
[1212302.630008] Call Trace:
[1212302.630008]  [<ffffffffa05070cd>] release_extent_buffer+0x3d/0xa0 [btrfs]
[1212302.630008]  [<ffffffffa04c2d9d>] btrfs_release_path+0x1d/0xa0 [btrfs]
[1212302.630008]  [<ffffffffa04c5c7e>] read_block_for_search.isra.33+0x13e/0x3a0 [btrfs]
[1212302.630008]  [<ffffffffa04c8094>] btrfs_search_slot+0x3f4/0xa80 [btrfs]
[1212302.630008]  [<ffffffffa04cf5d8>] lookup_inline_extent_backref+0xf8/0x630 [btrfs]
[1212302.630008]  [<ffffffffa04d13dd>] __btrfs_free_extent+0x11d/0xc40 [btrfs]
[1212302.630008]  [<ffffffffa04d64a4>] __btrfs_run_delayed_refs+0x394/0x11d0 [btrfs]
[1212302.630008]  [<ffffffffa04db379>] btrfs_run_delayed_refs.part.66+0x69/0x280 [btrfs]
[1212302.630008]  [<ffffffffa04ed2ad>] __btrfs_end_transaction+0x2ad/0x3d0 [btrfs]
[1212302.630008]  [<ffffffffa04f7505>] btrfs_evict_inode+0x4a5/0x500 [btrfs]
[1212302.630008]  [<ffffffff811b9e28>] evict+0xa8/0x190
[1212302.630008]  [<ffffffff811b0330>] do_unlinkat+0x1a0/0x2b0

I was also able to reproduce this on a 3.19 kernel, corresponding to Chris'
integration branch from about a month ago, running the following stress
test on a qemu/kvm guest (with 4 virtual cpus and 16Gb of ram):

  while true; do
     mkfs.btrfs -l 4096 -f -b `expr 20 \* 1024 \* 1024 \* 1024` /dev/sdd
     mount /dev/sdd /mnt
     snapshot_cmd="btrfs subvolume snapshot -r /mnt"
     snapshot_cmd="$snapshot_cmd /mnt/snap_\`date +'%H_%M_%S_%N'\`"
     fsstress -d /mnt -n 25000 -p 8 -x "$snapshot_cmd" -X 100
     umount /mnt
  done

Which usually triggers the BUG_ON within less than 24 hours:

[49558.618097] ------------[ cut here ]------------
[49558.619732] kernel BUG at fs/btrfs/extent_io.c:4551!
(...)
[49558.620031] CPU: 3 PID: 23908 Comm: fsstress Tainted: G        W      3.19.0-btrfs-next-7+ #3
[49558.620031] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[49558.620031] task: ffff8800319fc0d0 ti: ffff880220da8000 task.ti: ffff880220da8000
[49558.620031] RIP: 0010:[<ffffffffa0476b1a>]  [<ffffffffa0476b1a>] btrfs_release_extent_buffer_page+0x20/0xe9 [btrfs]
(...)
[49558.620031] Call Trace:
[49558.620031]  [<ffffffffa0476c73>] release_extent_buffer+0x90/0xd3 [btrfs]
[49558.620031]  [<ffffffff8142b10c>] ? _raw_spin_lock+0x3b/0x43
[49558.620031]  [<ffffffffa0477052>] ? free_extent_buffer+0x37/0x94 [btrfs]
[49558.620031]  [<ffffffffa04770ab>] free_extent_buffer+0x90/0x94 [btrfs]
[49558.620031]  [<ffffffffa04396d5>] btrfs_release_path+0x4a/0x69 [btrfs]
[49558.620031]  [<ffffffffa0444907>] __btrfs_free_extent+0x778/0x80c [btrfs]
[49558.620031]  [<ffffffffa044a485>] __btrfs_run_delayed_refs+0xad2/0xc62 [btrfs]
[49558.728054]  [<ffffffff811420d5>] ? kmemleak_alloc_recursive.constprop.52+0x16/0x18
[49558.728054]  [<ffffffffa044c1e8>] btrfs_run_delayed_refs+0x6d/0x1ba [btrfs]
[49558.728054]  [<ffffffffa045917f>] ? join_transaction.isra.9+0xb9/0x36b [btrfs]
[49558.728054]  [<ffffffffa045a75c>] btrfs_commit_transaction+0x4c/0x981 [btrfs]
[49558.728054]  [<ffffffffa0434f86>] btrfs_sync_fs+0xd5/0x10d [btrfs]
[49558.728054]  [<ffffffff81155923>] ? iterate_supers+0x60/0xc4
[49558.728054]  [<ffffffff8117966a>] ? do_sync_work+0x91/0x91
[49558.728054]  [<ffffffff8117968a>] sync_fs_one_sb+0x20/0x22
[49558.728054]  [<ffffffff81155939>] iterate_supers+0x76/0xc4
[49558.728054]  [<ffffffff811798e8>] sys_sync+0x55/0x83
[49558.728054]  [<ffffffff8142bbd2>] system_call_fastpath+0x12/0x17

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-05-11 07:59:11 -07:00
Forrest Liu 5d2361db48 Btrfs: btrfs_release_extent_buffer_page didn't free pages of dummy extent
btrfs_release_extent_buffer_page() can't handle dummy extent that
allocated by btrfs_clone_extent_buffer() properly. That is because
reference count of pages that allocated by btrfs_clone_extent_buffer()
was 2, 1 by alloc_page(), and another by attach_extent_buffer_page().

Running following command repeatly can check this memory leak problem

    btrfs inspect-internal inode-resolve 256 /mnt/btrfs

Signed-off-by: Chien-Kuan Yeh <ckya@synology.com>
Signed-off-by: Forrest Liu <forrestl@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-29 13:22:09 -07:00
Omar Sandoval 5ca64f45e9 btrfs: fix race on ENOMEM in alloc_extent_buffer
Consider the following interleaving of overlapping calls to
alloc_extent_buffer:

Call 1:

- Successfully allocates a few pages with find_or_create_page
- find_or_create_page fails, goto free_eb
- Unlocks the allocated pages

Call 2:
- Calls find_or_create_page and gets a page in call 1's extent_buffer
- Finds that the page is already associated with an extent_buffer
- Grabs a reference to the half-written extent_buffer and calls
  mark_extent_buffer_accessed on it

mark_extent_buffer_accessed will then try to call mark_page_accessed on
a null page and panic.

The fix is to decrement the reference count on the half-written
extent_buffer before unlocking the pages so call 2 won't use it. We
should also set exists = NULL in the case that we don't use exists to
avoid accidentally returning a freed extent_buffer in an error case.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-26 06:27:00 -07:00
Chengyu Song 26e726afe0 btrfs: incorrect handling for fiemap_fill_next_extent return
fiemap_fill_next_extent returns 0 on success, -errno on error, 1 if this was
the last extent that will fit in user array. If 1 is returned, the return
value may eventually returned to user space, which should not happen, according
to manpage of ioctl.

Signed-off-by: Chengyu Song <csong84@gatech.edu>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-26 18:10:24 -07:00
Linus Torvalds 521d474631 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Most of these are fixing extent reservation accounting, or corners
  with tree writeback during commit.

  Josef's set does add a test, which isn't strictly a fix, but it'll
  keep us from making this same mistake again"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix outstanding_extents accounting in DIO
  Btrfs: add sanity test for outstanding_extents accounting
  Btrfs: just free dummy extent buffers
  Btrfs: account merges/splits properly
  Btrfs: prepare block group cache before writing
  Btrfs: fix ASSERT(list_empty(&cur_trans->dirty_bgs_list)
  Btrfs: account for the correct number of extents for delalloc reservations
  Btrfs: fix merge delalloc logic
  Btrfs: fix comp_oper to get right order
  Btrfs: catch transaction abortion after waiting for it
  btrfs: fix sizeof format specifier in btrfs_check_super_valid()
2015-03-21 10:53:37 -07:00
Josef Bacik bcb7e449ec Btrfs: just free dummy extent buffers
If we fail during our sanity tests we could get NULL deref's because we unload
the module before the dummy extent buffers are free'd via RCU.  So check for
this case and just free the things directly.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2015-03-17 16:30:18 -04:00
Linus Torvalds 2b9fb532d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This pull is mostly cleanups and fixes:

   - The raid5/6 cleanups from Zhao Lei fixup some long standing warts
     in the code and add improvements on top of the scrubbing support
     from 3.19.

   - Josef has round one of our ENOSPC fixes coming from large btrfs
     clusters here at FB.

   - Dave Sterba continues a long series of cleanups (thanks Dave), and
     Filipe continues hammering on corner cases in fsync and others

  This all was held up a little trying to track down a use-after-free in
  btrfs raid5/6.  It's not clear yet if this is just made easier to
  trigger with this pull or if its a new bug from the raid5/6 cleanups.
  Dave Sterba is the only one to trigger it so far, but he has a
  consistent way to reproduce, so we'll get it nailed shortly"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (68 commits)
  Btrfs: don't remove extents and xattrs when logging new names
  Btrfs: fix fsync data loss after adding hard link to inode
  Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group
  Btrfs: account for large extents with enospc
  Btrfs: don't set and clear delalloc for O_DIRECT writes
  Btrfs: only adjust outstanding_extents when we do a short write
  btrfs: Fix out-of-space bug
  Btrfs: scrub, fix sleep in atomic context
  Btrfs: fix scheduler warning when syncing log
  Btrfs: Remove unnecessary placeholder in btrfs_err_code
  btrfs: cleanup init for list in free-space-cache
  btrfs: delete chunk allocation attemp when setting block group ro
  btrfs: clear bio reference after submit_one_bio()
  Btrfs: fix scrub race leading to use-after-free
  Btrfs: add missing cleanup on sysfs init failure
  Btrfs: fix race between transaction commit and empty block group removal
  btrfs: add more checks to btrfs_read_sys_array
  btrfs: cleanup, rename a few variables in btrfs_read_sys_array
  btrfs: add checks for sys_chunk_array sizes
  btrfs: more superblock checks, lower bounds on devices and sectorsize/nodesize
  ...
2015-02-19 14:36:00 -08:00