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1216 Commits (1eff9d322a444245c67515edb52bc0eb68374aa8)

Author SHA1 Message Date
Filipe Manana c1aa45759e Btrfs: fix shrinking truncate when the no_holes feature is enabled
If the no_holes feature is enabled, we attempt to shrink a file to a size
that ends up in the middle of a hole and we don't have any file extent
items in the fs/subvol tree that go beyond the new file size (or any
ordered extents that will insert such file extent items), we end up not
updating the inode's disk_i_size, we only update the inode's i_size.

This means that after unmounting and mounting the filesystem, or after
the inode is evicted and reloaded, its i_size ends up being incorrect
(an inode's i_size is set to the disk_i_size field when an inode is
loaded). This happens when btrfs_truncate_inode_items() doesn't find
any file extent items to drop - in this case it never makes a call to
btrfs_ordered_update_i_size() in order to update the inode's disk_i_size.

Example reproducer:

  $ mkfs.btrfs -O no-holes -f /dev/sdd
  $ mount /dev/sdd /mnt

  # Create our test file with some data and durably persist it.
  $ xfs_io -f -c "pwrite -S 0xaa 0 128K" /mnt/foo
  $ sync

  # Append some data to the file, increasing its size, and leave a hole
  # between the old size and the start offset if the following write. So
  # our file gets a hole in the range [128Kb, 256Kb[.
  $ xfs_io -c "truncate 160K" /mnt/foo

  # We expect to see our file with a size of 160Kb, with the first 128Kb
  # of data all having the value 0xaa and the remaining 32Kb of data all
  # having the value 0x00.
  $ od -t x1 /mnt/foo
  0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
  *
  0400000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  *
  0500000

  # Now cleanly unmount and mount again the filesystem.
  $ umount /mnt
  $ mount /dev/sdd /mnt

  # We expect to get the same result as before, a file with a size of
  # 160Kb, with the first 128Kb of data all having the value 0xaa and the
  # remaining 32Kb of data all having the value 0x00.
  $ od -t x1 /mnt/foo
  0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
  *
  0400000

In the example above the file size/data do not match what they were before
the remount.

Fix this by always calling btrfs_ordered_update_i_size() with a size
matching the size the file was truncated to if btrfs_truncate_inode_items()
is not called for a log tree and no file extent items were dropped. This
ensures the same behaviour as when the no_holes feature is not enabled.

A test case for fstests follows soon.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-07-11 22:33:14 +01:00
Liu Bo ddba1bfc23 Btrfs: fix warning of bytes_may_use
While running generic/019, dmesg got several warnings from
btrfs_free_reserved_data_space().

Test generic/019 produces some disk failures so sumbit dio will get errors,
in which case, btrfs_direct_IO() goes to the error handling and free
bytes_may_use, but the problem is that bytes_may_use has been free'd
during get_block().

This adds a runtime flag to show if we've gone through get_block(), if so,
don't do the cleanup work.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:21 -07:00
Liu Bo ad9ee2053f Btrfs: fix hang when failing to submit bio of directIO
The hang is uncoverd by generic/019.

btrfs_endio_direct_write() skips the "finish_ordered_fn" part when it hits
an error, thus those added ordered extents will never get processed, which
block processes that waiting for them via btrfs_start_ordered_extent().

This fixes the above, and meanwhile finish_ordered_fn will do the space
accounting work.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:20 -07:00
Filipe Manana 9c6429d96d Btrfs: fix a comment in inode.c:evict_inode_truncate_pages()
The comment was not correct about the part where it says the endio
callback of the bio might have not yet been called - update it
to mention that by that time the endio callback execution might
still be in progress only.

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>
2015-07-01 17:17:19 -07:00
Filipe Manana 61de718fce Btrfs: fix memory corruption on failure to submit bio for direct IO
If we fail to submit a bio for a direct IO request, we were grabbing the
corresponding ordered extent and decrementing its reference count twice,
once for our lookup reference and once for the ordered tree reference.
This was a problem because it caused the ordered extent to be freed
without removing it from the ordered tree and any lists it might be
attached to, leaving dangling pointers to the ordered extent around.
Example trace with CONFIG_DEBUG_PAGEALLOC=y:

[161779.858707] BUG: unable to handle kernel paging request at 0000000087654330
[161779.859983] IP: [<ffffffff8124ca68>] rb_prev+0x22/0x3b
[161779.860636] PGD 34d818067 PUD 0
[161779.860636] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
(...)
[161779.860636] Call Trace:
[161779.860636]  [<ffffffffa06b36a6>] __tree_search+0xd9/0xf9 [btrfs]
[161779.860636]  [<ffffffffa06b3708>] tree_search+0x42/0x63 [btrfs]
[161779.860636]  [<ffffffffa06b4868>] ? btrfs_lookup_ordered_range+0x2d/0xa5 [btrfs]
[161779.860636]  [<ffffffffa06b4873>] btrfs_lookup_ordered_range+0x38/0xa5 [btrfs]
[161779.860636]  [<ffffffffa06aab8e>] btrfs_get_blocks_direct+0x11b/0x615 [btrfs]
[161779.860636]  [<ffffffff8119727f>] do_blockdev_direct_IO+0x5ff/0xb43
[161779.860636]  [<ffffffffa06aaa73>] ? btrfs_page_exists_in_range+0x1ad/0x1ad [btrfs]
[161779.860636]  [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636]  [<ffffffff811977f5>] __blockdev_direct_IO+0x32/0x34
[161779.860636]  [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636]  [<ffffffffa06a10ae>] btrfs_direct_IO+0x198/0x21f [btrfs]
[161779.860636]  [<ffffffffa06a2c9a>] ? btrfs_get_extent_fiemap+0x1bc/0x1bc [btrfs]
[161779.860636]  [<ffffffff81112ca1>] generic_file_direct_write+0xb3/0x128
[161779.860636]  [<ffffffffa06affaa>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
[161779.860636]  [<ffffffffa06b004c>] btrfs_file_write_iter+0x201/0x3e0 [btrfs]
(...)

We were also not freeing the btrfs_dio_private we allocated previously,
which kmemleak reported with the following trace in its sysfs file:

unreferenced object 0xffff8803f553bf80 (size 96):
  comm "xfs_io", pid 4501, jiffies 4295039588 (age 173.936s)
  hex dump (first 32 bytes):
    88 6c 9b f5 02 88 ff ff 00 00 00 00 00 00 00 00  .l..............
    00 00 00 00 00 00 00 00 00 00 c4 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81161ffe>] create_object+0x172/0x29a
    [<ffffffff8145870f>] kmemleak_alloc+0x25/0x41
    [<ffffffff81154e64>] kmemleak_alloc_recursive.constprop.40+0x16/0x18
    [<ffffffff811579ed>] kmem_cache_alloc_trace+0xfb/0x148
    [<ffffffffa03d8cff>] btrfs_submit_direct+0x65/0x16a [btrfs]
    [<ffffffff811968dc>] dio_bio_submit+0x62/0x8f
    [<ffffffff811975fe>] do_blockdev_direct_IO+0x97e/0xb43
    [<ffffffff811977f5>] __blockdev_direct_IO+0x32/0x34
    [<ffffffffa03d70ae>] btrfs_direct_IO+0x198/0x21f [btrfs]
    [<ffffffff81112ca1>] generic_file_direct_write+0xb3/0x128
    [<ffffffffa03e604d>] btrfs_file_write_iter+0x201/0x3e0 [btrfs]
    [<ffffffff8116586a>] __vfs_write+0x7c/0xa5
    [<ffffffff81165da9>] vfs_write+0xa0/0xe4
    [<ffffffff81166675>] SyS_pwrite64+0x64/0x82
    [<ffffffff81464fd7>] system_call_fastpath+0x12/0x6f
    [<ffffffffffffffff>] 0xffffffffffffffff

For read requests we weren't doing any cleanup either (none of the work
done by btrfs_endio_direct_read()), so a failure submitting a bio for a
read request would leave a range in the inode's io_tree locked forever,
blocking any future operations (both reads and writes) against that range.

So fix this by making sure we do the same cleanup that we do for the case
where the bio submission succeeds.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:18 -07:00
Filipe Manana 6ca0709756 Btrfs: fix hang during inode eviction due to concurrent readahead
Zygo Blaxell and other users have reported occasional hangs while an
inode is being evicted, leading to traces like the following:

[ 5281.972322] INFO: task rm:20488 blocked for more than 120 seconds.
[ 5281.973836]       Not tainted 4.0.0-rc5-btrfs-next-9+ #2
[ 5281.974818] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 5281.976364] rm              D ffff8800724cfc38     0 20488   7747 0x00000000
[ 5281.977506]  ffff8800724cfc38 ffff8800724cfc38 ffff880065da5c50 0000000000000001
[ 5281.978461]  ffff8800724cffd8 ffff8801540a5f50 0000000000000008 ffff8801540a5f78
[ 5281.979541]  ffff8801540a5f50 ffff8800724cfc58 ffffffff8143107e 0000000000000123
[ 5281.981396] Call Trace:
[ 5281.982066]  [<ffffffff8143107e>] schedule+0x74/0x83
[ 5281.983341]  [<ffffffffa03b33cf>] wait_on_state+0xac/0xcd [btrfs]
[ 5281.985127]  [<ffffffff81075cd6>] ? signal_pending_state+0x31/0x31
[ 5281.986715]  [<ffffffffa03b4b71>] wait_extent_bit.constprop.32+0x7c/0xde [btrfs]
[ 5281.988680]  [<ffffffffa03b540b>] lock_extent_bits+0x5d/0x88 [btrfs]
[ 5281.990200]  [<ffffffffa03a621d>] btrfs_evict_inode+0x24e/0x5be [btrfs]
[ 5281.991781]  [<ffffffff8116964d>] evict+0xa0/0x148
[ 5281.992735]  [<ffffffff8116a43d>] iput+0x18f/0x1e5
[ 5281.993796]  [<ffffffff81160d4a>] do_unlinkat+0x15b/0x1fa
[ 5281.994806]  [<ffffffff81435b54>] ? ret_from_sys_call+0x1d/0x58
[ 5281.996120]  [<ffffffff8107d314>] ? trace_hardirqs_on_caller+0x18f/0x1ab
[ 5281.997562]  [<ffffffff8123960b>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 5281.998815]  [<ffffffff81161a16>] SyS_unlinkat+0x29/0x2b
[ 5281.999920]  [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[ 5282.001299] 1 lock held by rm/20488:
[ 5282.002066]  #0:  (sb_writers#12){.+.+.+}, at: [<ffffffff8116dd81>] mnt_want_write+0x24/0x4b

This happens when we have readahead, which calls readpages(), happening
right before the inode eviction handler is invoked. So the reason is
essentially:

1) readpages() is called while a reference on the inode is held, so
   eviction can not be triggered before readpages() returns. It also
   locks one or more ranges in the inode's io_tree (which is done at
   extent_io.c:__do_contiguous_readpages());

2) readpages() submits several read bios, all with an end io callback
   that runs extent_io.c:end_bio_extent_readpage() and that is executed
   by other task when a bio finishes, corresponding to a work queue
   (fs_info->end_io_workers) worker kthread. This callback unlocks
   the ranges in the inode's io_tree that were previously locked in
   step 1;

3) readpages() returns, the reference on the inode is dropped;

4) One or more of the read bios previously submitted are still not
   complete (their end io callback was not yet invoked or has not
   yet finished execution);

5) Inode eviction is triggered (through an unlink call for example).
   The inode reference count was not incremented before submitting
   the read bios, therefore this is possible;

6) The eviction handler starts executing and enters the loop that
   iterates over all extent states in the inode's io_tree;

7) The loop picks one extent state record and uses its ->start and
   ->end fields, after releasing the inode's io_tree spinlock, to
   call lock_extent_bits() and clear_extent_bit(). The call to lock
   the range [state->start, state->end] blocks because the whole
   range or a part of it was locked by the previous call to
   readpages() and the corresponding end io callback, which unlocks
   the range was not yet executed;

8) The end io callback for the read bio is executed and unlocks the
   range [state->start, state->end] (or a superset of that range).
   And at clear_extent_bit() the extent_state record state is used
   as a second argument to split_state(), which sets state->start to
   a larger value;

9) The task executing the eviction handler is woken up by the task
   executing the bio's end io callback (through clear_state_bit) and
   the eviction handler locks the range
   [old value for state->start, state->end]. Shortly after, when
   calling clear_extent_bit(), it unlocks the range
   [new value for state->start, state->end], so it ends up unlocking
   only part of the range that it locked, leaving an extent state
   record in the io_tree that represents the unlocked subrange;

10) The eviction handler loop, in its next iteration, gets the
    extent_state record for the subrange that it did not unlock in the
    previous step and then tries to lock it, resulting in an hang.

So fix this by not using the ->start and ->end fields of an existing
extent_state record. This is a simple solution, and an alternative
could be to bump the inode's reference count before submitting each
read bio and having it dropped in the bio's end io callback. But that
would be a more invasive/complex change and would not protect against
other possible places that are not holding a reference on the inode
as well. Something to consider in the future.

Many thanks to Zygo Blaxell for reporting, in the mailing list, the
issue, a set of scripts to trigger it and testing this fix.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Tested-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:09 -07:00
Linus Torvalds 64887b6882 Merge branch 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "A few more btrfs fixes.

  These range from corners Filipe found in the new free space cache
  writeback to a grab bag of fixes from the list"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: btrfs_release_extent_buffer_page didn't free pages of dummy extent
  Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.
  btrfs: unlock i_mutex after attempting to delete subvolume during send
  btrfs: check io_ctl_prepare_pages return in __btrfs_write_out_cache
  btrfs: fix race on ENOMEM in alloc_extent_buffer
  btrfs: handle ENOMEM in btrfs_alloc_tree_block
  Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
  Btrfs: don't check for delalloc_bytes in cache_save_setup
  Btrfs: fix deadlock when starting writeback of bg caches
  Btrfs: fix race between start dirty bg cache writeout and bg deletion
2015-05-01 07:46:21 -07:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Yang Dongsheng 6e17d30bfa Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.
We need to fill inode when we found a node for it in delayed_nodes_tree.
But we did not fill the ->last_trans currently, it will cause the test
of xfstest/generic/311 fail. Scenario of the 311 is shown as below:

Problem:
	(1). test_fd = open(fname, O_RDWR|O_DIRECT)
	(2). pwrite(test_fd, buf, 4096, 0)
	(3). close(test_fd)
	(4). drop_all_caches()	<-------- "echo 3 > /proc/sys/vm/drop_caches"
	(5). test_fd = open(fname, O_RDWR|O_DIRECT)
	(6). fsync(test_fd);
				<-------- we did not get the correct log entry for the file
Reason:
	When we re-open this file in (5), we would find a node
in delayed_nodes_tree and fill the inode we are lookup with the
information. But the ->last_trans is not filled, then the fsync()
will check the ->last_trans and found it's 0 then say this inode
is already in our tree which is commited, not recording the extents
for it.

Fix:
	This patch fill the ->last_trans properly and set the
runtime_flags if needed in this situation. Then we can get the
log entries we expected after (6) and generic/311 passed.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-26 06:27:03 -07:00
Jens Axboe fe0f07d08e direct-io: only inc/dec inode->i_dio_count for file systems
do_blockdev_direct_IO() increments and decrements the inode
->i_dio_count for each IO operation. It does this to protect against
truncate of a file. Block devices don't need this sort of protection.

For a capable multiqueue setup, this atomic int is the only shared
state between applications accessing the device for O_DIRECT, and it
presents a scaling wall for that. In my testing, as much as 30% of
system time is spent incrementing and decrementing this value. A mixed
read/write workload improved from ~2.5M IOPS to ~9.6M IOPS, with
better latencies too. Before:

clat percentiles (usec):
 |  1.00th=[   33],  5.00th=[   34], 10.00th=[   34], 20.00th=[   34],
 | 30.00th=[   34], 40.00th=[   34], 50.00th=[   35], 60.00th=[   35],
 | 70.00th=[   35], 80.00th=[   35], 90.00th=[   37], 95.00th=[   80],
 | 99.00th=[   98], 99.50th=[  151], 99.90th=[  155], 99.95th=[  155],
 | 99.99th=[  165]

After:

clat percentiles (usec):
 |  1.00th=[   95],  5.00th=[  108], 10.00th=[  129], 20.00th=[  149],
 | 30.00th=[  155], 40.00th=[  161], 50.00th=[  167], 60.00th=[  171],
 | 70.00th=[  177], 80.00th=[  185], 90.00th=[  201], 95.00th=[  270],
 | 99.00th=[  390], 99.50th=[  398], 99.90th=[  418], 99.95th=[  422],
 | 99.99th=[  438]

In other setups, Robert Elliott reported seeing good performance
improvements:

https://lkml.org/lkml/2015/4/3/557

The more applications accessing the device, the worse it gets.

Add a new direct-io flags, DIO_SKIP_DIO_COUNT, which tells
do_blockdev_direct_IO() that it need not worry about incrementing
or decrementing the inode i_dio_count for this caller.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Elliott, Robert (Server Storage) <elliott@hp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-24 15:45:28 -04:00
Linus Torvalds ba0e4ae88f Merge branch 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "I've been running these through a longer set of load tests because my
  commits change the free space cache writeout.  It fixes commit stalls
  on large filesystems (~20T space used and up) that we have been
  triggering here.  We were seeing new writers blocked for 10 seconds or
  more during commits, which is far from good.

  Josef and I fixed up ENOSPC aborts when deleting huge files (3T or
  more), that are triggered because our metadata reservations were not
  properly accounting for crcs and were not replenishing during the
  truncate.

  Also in this series, a number of qgroup fixes from Fujitsu and Dave
  Sterba collected most of the pending cleanups from the list"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (93 commits)
  btrfs: quota: Update quota tree after qgroup relationship change.
  btrfs: quota: Automatically update related qgroups or mark INCONSISTENT flags when assigning/deleting a qgroup relations.
  btrfs: qgroup: clear STATUS_FLAG_ON in disabling quota.
  btrfs: Update btrfs qgroup status item when rescan is done.
  btrfs: qgroup: Fix dead judgement on qgroup_rescan_leaf() return value.
  btrfs: Don't allow subvolid >= (1 << BTRFS_QGROUP_LEVEL_SHIFT) to be created
  btrfs: Check qgroup level in kernel qgroup assign.
  btrfs: qgroup: allow to remove qgroup which has parent but no child.
  btrfs: qgroup: return EINVAL if level of parent is not higher than child's.
  btrfs: qgroup: do a reservation in a higher level.
  Btrfs: qgroup, Account data space in more proper timings.
  Btrfs: qgroup: Introduce a may_use to account space_info->bytes_may_use.
  Btrfs: qgroup: free reserved in exceeding quota.
  Btrfs: qgroup: cleanup, remove an unsued parameter in btrfs_create_qgroup().
  btrfs: qgroup: fix limit args override whole limit struct
  btrfs: qgroup: update limit info in function btrfs_run_qgroups().
  btrfs: qgroup: consolidate the parameter of fucntion update_qgroup_limit_item().
  btrfs: qgroup: update qgroup in memory at the same time when we update it in btree.
  btrfs: qgroup: inherit limit info from srcgroup in creating snapshot.
  btrfs: Support busy loop of write and delete
  ...
2015-04-24 07:40:02 -07:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Dongsheng Yang e2d1f92399 btrfs: qgroup: do a reservation in a higher level.
There are two problems in qgroup:

a). The PAGE_CACHE is 4K, even when we are writing a data of 1K,
qgroup will reserve a 4K size. It will cause the last 3K in a qgroup
is not available to user.

b). When user is writing a inline data, qgroup will not reserve it,
it means this is a window we can exceed the limit of a qgroup.

The main idea of this patch is reserving the data size of write_bytes
rather than the reserve_bytes. It means qgroup will not care about
the data size btrfs will reserve for user, but only care about the
data size user is going to write. Then reserve it when user want to
write and release it in transaction committed.

In this way, qgroup can be released from the complex procedure in
btrfs and only do the reserve when user want to write and account
when the data is written in commit_transaction().

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:50 -07:00
Dongsheng Yang 31193213f1 Btrfs: qgroup: Introduce a may_use to account space_info->bytes_may_use.
Currently, for pre_alloc or delay_alloc, the bytes will be accounted
in space_info by the three guys.
space_info->bytes_may_use --- space_info->reserved --- space_info->used.
But on the other hand, in qgroup, there are only two counters to account the
bytes, qgroup->reserved and qgroup->excl. And qg->reserved accounts
bytes in space_info->bytes_may_use and qg->excl accounts bytes in
space_info->used. So the bytes in space_info->reserved is not accounted
in qgroup. If so, there is a window we can exceed the quota limit when
bytes is in space_info->reserved.

Example:
	# btrfs quota enable /mnt
	# btrfs qgroup limit -e 10M /mnt
	# for((i=0;i<20;i++));do fallocate -l 1M /mnt/data$i; done
	# sync
	# btrfs qgroup show -pcre /mnt
qgroupid rfer     excl     max_rfer max_excl parent  child
-------- ----     ----     -------- -------- ------  -----
0/5      20987904 20987904 0        10485760 ---     ---

qg->excl is 20987904 larger than max_excl 10485760.

This patch introduce a new counter named may_use to qgroup, then
there are three counters in qgroup to account bytes in space_info
as below.
space_info->bytes_may_use --- space_info->reserved --- space_info->used.
qgroup->may_use           --- qgroup->reserved     --- qgroup->excl

With this patch applied:
	# btrfs quota enable /mnt
	# btrfs qgroup limit -e 10M /mnt
	# for((i=0;i<20;i++));do fallocate -l 1M /mnt/data$i; done
fallocate: /mnt/data9: fallocate failed: Disk quota exceeded
fallocate: /mnt/data10: fallocate failed: Disk quota exceeded
fallocate: /mnt/data11: fallocate failed: Disk quota exceeded
fallocate: /mnt/data12: fallocate failed: Disk quota exceeded
fallocate: /mnt/data13: fallocate failed: Disk quota exceeded
fallocate: /mnt/data14: fallocate failed: Disk quota exceeded
fallocate: /mnt/data15: fallocate failed: Disk quota exceeded
fallocate: /mnt/data16: fallocate failed: Disk quota exceeded
fallocate: /mnt/data17: fallocate failed: Disk quota exceeded
fallocate: /mnt/data18: fallocate failed: Disk quota exceeded
fallocate: /mnt/data19: fallocate failed: Disk quota exceeded
	# sync
	# btrfs qgroup show -pcre /mnt
qgroupid rfer    excl    max_rfer max_excl parent  child
-------- ----    ----    -------- -------- ------  -----
0/5      9453568 9453568 0        10485760 ---     ---

Reported-by: Cyril SCETBON <cyril.scetbon@free.fr>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:47 -07:00
Zhao Lei d7c151717a btrfs: Fix NO_SPACE bug caused by delayed-iput
Steps to reproduce:
  while true; do
    dd if=/dev/zero of=/btrfs_dir/file count=[fs_size * 75%]
    rm /btrfs_dir/file
    sync
  done

  And we'll see dd failed because btrfs return NO_SPACE.

Reason:
  Normally, btrfs_commit_transaction() call btrfs_run_delayed_iputs()
  in end to free fs space for next write, but sometimes it hadn't
  done work on time, because btrfs-cleaner thread get delayed-iputs
  from list before, but do iput() after next write.

  This is log:
  [ 2569.050776] comm=btrfs-cleaner func=btrfs_evict_inode() begin

  [ 2569.084280] comm=sync func=btrfs_commit_transaction() call btrfs_run_delayed_iputs()
  [ 2569.085418] comm=sync func=btrfs_commit_transaction() done btrfs_run_delayed_iputs()
  [ 2569.087554] comm=sync func=btrfs_commit_transaction() end

  [ 2569.191081] comm=dd begin
  [ 2569.790112] comm=dd func=__btrfs_buffered_write() ret=-28

  [ 2569.847479] comm=btrfs-cleaner func=add_pinned_bytes() 0 + 32677888 = 32677888
  [ 2569.849530] comm=btrfs-cleaner func=add_pinned_bytes() 32677888 + 23834624 = 56512512
  ...
  [ 2569.903893] comm=btrfs-cleaner func=add_pinned_bytes() 943976448 + 21762048 = 965738496
  [ 2569.908270] comm=btrfs-cleaner func=btrfs_evict_inode() end

Fix:
  Make btrfs_commit_transaction() wait current running btrfs-cleaner's
  delayed-iputs() done in end.

Test:
  Use script similar to above(more complex),
  before patch:
    7 failed in 100 * 20 loop.
  after patch:
    0 failed in 100 * 20 loop.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:27:41 -07:00
Omar Sandoval 22c6186ece direct_IO: remove rw from a_ops->direct_IO()
Now that no one is using rw, remove it completely.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:45 -04:00
Omar Sandoval 6f67376318 direct_IO: use iov_iter_rw() instead of rw everywhere
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:45 -04:00
Omar Sandoval 17f8c842d2 Remove rw from {,__,do_}blockdev_direct_IO()
Most filesystems call through to these at some point, so we'll start
here.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:44 -04:00
Al Viro c0fec3a98b Merge branch 'iocb' into for-next 2015-04-11 22:24:41 -04:00
Josef Bacik 3bce876fd5 Btrfs: don't steal from the global reserve if we don't have the space
btrfs_evict_inode() needs to be more careful about stealing from the
global_rsv.  We dont' want to end up aborting commit with ENOSPC just
because the evict_inode code was too greedy.

Signed-off-by: Chris Mason <clm@fb.com>
2015-04-10 14:06:59 -07:00
Chris Mason 28f75a0e6c Btrfs: refill block reserves during truncate
When truncate starts, it allocates some space in the block reserves so
that we'll have enough to update metadata along the way.

For very large files, we can easily go through all of that space as we
loop through the extents.  This changes truncate to refill the space
reservation as it progresses through the file.

Signed-off-by: Chris Mason <clm@fb.com>
2015-04-10 14:06:34 -07:00
Josef Bacik 1262133b8d Btrfs: account for crcs in delayed ref processing
As we delete large extents, we end up doing huge amounts of COW in order
to delete the corresponding crcs.  This adds accounting so that we keep
track of that space and flushing of delayed refs so that we don't build
up too much delayed crc work.

This helps limit the delayed work that must be done at commit time and
tries to avoid ENOSPC aborts because the crcs eat all the global
reserves.

Signed-off-by: Chris Mason <clm@fb.com>
2015-04-10 14:04:47 -07:00
Chris Mason 28ed1345a5 btrfs: actively run the delayed refs while deleting large files
When we are deleting large files with large extents, we are building up
a huge set of delayed refs for processing.  Truncate isn't checking
often enough to see if we need to back off and process those, or let
a commit proceed.

The end result is long stalls after the rm, and very long commit times.
During the commits, other processes back up waiting to start new
transactions and we get into trouble.

Signed-off-by: Chris Mason <clm@fb.com>
2015-04-10 14:00:14 -07:00
Guenter Roeck 4a3d1caf8a fs: btrfs: Add missing include file
Building alpha:allmodconfig fails with

fs/btrfs/inode.c: In function 'check_direct_IO':
fs/btrfs/inode.c:8050:2: error: implicit declaration of function 'iov_iter_alignment'

due to a missing include file.

Fixes: 3737c63e1fb0 ("fs: move struct kiocb to fs.h")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-01 12:32:07 -07:00
Christoph Hellwig e2e40f2c1e fs: move struct kiocb to fs.h
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-25 20:28:11 -04:00
Chris Mason 9deed229fa Merge branch 'cleanups-for-4.1-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.1 2015-03-25 10:43:16 -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 e1cbbfa5f5 Btrfs: fix outstanding_extents accounting in DIO
We are keeping track of how many extents we need to reserve properly based on
the amount we want to write, but we were still incrementing outstanding_extents
if we wrote less than what we requested.  This isn't quite right since we will
be limited to our max extent size.  So instead lets do something horrible!  Keep
track of how many outstanding_extents we reserved, and decrement each time we
allocate an extent.  If we use our entire reserve make sure to jack up
outstanding_extents on the inode so the accounting works out properly.  Thanks,

Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2015-03-17 16:36:35 -04:00
Josef Bacik 6a3891c551 Btrfs: add sanity test for outstanding_extents accounting
I introduced a regression wrt outstanding_extents accounting.  These are tricky
areas that aren't easily covered by xfstests as we could change MAX_EXTENT_SIZE
at any time.  So add sanity tests to cover the various conditions that are
tricky in order to make sure we don't introduce regressions in the future.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2015-03-17 16:36:31 -04:00
Josef Bacik ba11721355 Btrfs: account merges/splits properly
My fix

Btrfs: fix merge delalloc logic

only fixed half of the problems, it didn't fix the case where we have two large
extents on either side and then join them together with a new small extent.  We
need to instead keep track of how many extents we have accounted for with each
side of the new extent, and then see how many extents we need for the new large
extent.  If they match then we know we need to keep our reservation, otherwise
we need to drop our reservation.  This shows up with a case like this

[BTRFS_MAX_EXTENT_SIZE+4K][4K HOLE][BTRFS_MAX_EXTENT_SIZE+4K]

Previously the logic would have said that the number extents required for the
new size (3) is larger than the number of extents required for the largest side
(2) therefore we need to keep our reservation.  But this isn't the case, since
both sides require a reservation of 2 which leads to 4 for the whole range
currently reserved, but we only need 3, so we need to drop one of the
reservations.  The same problem existed for splits, we'd think we only need 3
extents when creating the hole but in reality we need 4.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2015-03-17 16:28:21 -04:00
Josef Bacik 8461a3de77 Btrfs: fix merge delalloc logic
My patch to properly count outstanding extents wrt MAX_EXTENT_SIZE introduced a
regression when re-dirtying already dirty areas.  We have logic in split to make
sure we are taking the largest space into account but didn't have it for merge,
so it was sometimes making us think we were turning a tiny extent into a huge
extent, when in reality we already had a huge extent and needed to use the other
side in our logic.  This fixes the regression that was reported by a user on
list.  Thanks,

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-13 13:46:59 -07:00
Linus Torvalds 84399bb075 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Outside of misc fixes, Filipe has a few fsync corners and we're
  pulling in one more of Josef's fixes from production use here"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs:__add_inode_ref: out of bounds memory read when looking for extended ref.
  Btrfs: fix data loss in the fast fsync path
  Btrfs: remove extra run_delayed_refs in update_cowonly_root
  Btrfs: incremental send, don't rename a directory too soon
  btrfs: fix lost return value due to variable shadowing
  Btrfs: do not ignore errors from btrfs_lookup_xattr in do_setxattr
  Btrfs: fix off-by-one logic error in btrfs_realloc_node
  Btrfs: add missing inode update when punching hole
  Btrfs: abort the transaction if we fail to update the free space cache inode
  Btrfs: fix fsync race leading to ordered extent memory leaks
2015-03-06 13:52:54 -08:00
David Sterba 31e818fe73 btrfs: cleanup, use kmalloc_array/kcalloc array helpers
Convert kmalloc(nr * size, ..) to kmalloc_array that does additional
overflow checks, the zeroing variant is kcalloc.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-03-03 17:23:58 +01:00
David Sterba 1932b7be97 btrfs: fix lost return value due to variable shadowing
A block-local variable stores error code but btrfs_get_blocks_direct may
not return it in the end as there's a ret defined in the function scope.

CC: <stable@vger.kernel.org>	# 3.6+
Fixes: d187663ef2 ("Btrfs: lock extents as we map them in DIO")
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-02 14:04:45 -08:00
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
Josef Bacik dcab6a3b2a Btrfs: account for large extents with enospc
On our gluster boxes we stream large tar balls of backups onto our fses.  With
160gb of ram this means we get really large contiguous ranges of dirty data, but
the way our ENOSPC stuff works is that as long as it's contiguous we only hold
metadata reservation for one extent.  The problem is we limit our extents to
128mb, so we'll end up with at least 800 extents so our enospc accounting is
quite a bit lower than what we need.  To keep track of this make sure we
increase outstanding_extents for every multiple of the max extent size so we can
be sure to have enough reserved metadata space.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-02-14 08:22:48 -08:00
Josef Bacik 3266789f9d Btrfs: don't set and clear delalloc for O_DIRECT writes
We do this to get the space accounting, but this is just needless churn on the
io_tree, so just drop setting/clearing delalloc and just drop the reserved data
space when we have a successfull allocation.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-02-14 08:19:14 -08:00
Josef Bacik 3e05bde8c3 Btrfs: only adjust outstanding_extents when we do a short write
We have this weird dance where we always inc outstanding_extents when we do a
O_DIRECT write, even if we allocate the entire range.  To get around this we
also drop the metadata space if we successfully write.  This is an unnecessary
dance, we only need to jack up outstanding_extents if we don't satisfy the
entire range request in get_blocks_direct, otherwise we are good using our
original reservation.  So drop the unconditional inc and the drop of the
metadata space that we have for the unconditional inc.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-02-14 08:19:14 -08:00
chandan r 9cc97d6462 Btrfs: Add code to support file creation time
This patch adds a new member to the 'struct btrfs_inode' structure to hold
the file creation time.

Signed-off-by: chandan <chandanrmail@gmail.com>
[refreshed, removed btrfs_inode_otime]
Signed-off-by: David Sterba <dsterba@suse.cz>

Signed-off-by: Chris Mason <clm@fb.com>
2015-02-02 18:39:16 -08:00
David Sterba a937b9791e btrfs: kill btrfs_inode_*time helpers
They just opencode taking address of the timespec member.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-02-02 18:39:07 -08:00
Zhao Lei ffe2d2034b Btrfs: Introduce BTRFS_BLOCK_GROUP_RAID56_MASK to check raid56 simply
So we can check raid56 with:
 (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
instead of long:
 (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-01-21 18:06:49 -08:00
David Sterba 9ee49a047d btrfs: switch extent_state state to unsigned
Currently there's a 4B hole in the structure between refs and state and there
are only 16 bits used so we can make it unsigned. This will get a better
packing and may save some stack space for local variables.

The size of extent_state gets reduced by 8B and there are usually a lot
of slab objects.

struct extent_state {
	u64                        start;                /*     0     8 */
	u64                        end;                  /*     8     8 */
	struct rb_node             rb_node;              /*    16    24 */
	wait_queue_head_t          wq;                   /*    40    24 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	atomic_t                   refs;                 /*    64     4 */

	/* XXX 4 bytes hole, try to pack */

	long unsigned int          state;                /*    72     8 */
	u64                        private;              /*    80     8 */

	/* size: 88, cachelines: 2, members: 7 */
	/* sum members: 84, holes: 1, sum holes: 4 */
	/* last cacheline: 24 bytes */
};

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-01-21 18:02:04 -08:00
David Sterba f0954c6637 btrfs: update message levels after checksum errors
The errors are worth noting and might get missed with INFO level.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-01-21 18:02:03 -08:00
David Sterba 68b663d13c btrfs: update message levels for errors
Several messages that point to some internal problem, level INFO is
wrong here.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-01-21 18:02:03 -08:00
Christoph Hellwig b83ae6d421 fs: remove mapping->backing_dev_info
Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-20 14:03:05 -07:00
David Sterba 1d4c08e0a6 btrfs: expand btrfs_find_item if found_key is NULL
If the found_key is NULL, then btrfs_find_item becomes a verbose wrapper
for simple btrfs_search_slot.

After we've removed all such callers, passing a NULL key is not valid
anymore.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-01-14 19:23:48 +01:00
Linus Torvalds 03c751a5e1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "None of these are huge, but my commit does fix a regression from 3.18
  that could cause lost files during log replay.

  This also adds Dave Sterba to the list of Btrfs maintainers.  It
  doesn't mean we're doing things differently, but Dave has really been
  helping with the maintainer workload for years"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: don't delay inode ref updates during log replay
  Btrfs: correctly get tree level in tree_backref_for_extent
  Btrfs: call inode_dec_link_count() on mkdir error path
  Btrfs: abort transaction if we don't find the block group
  Btrfs, scrub: uninitialized variable in scrub_extent_for_parity()
  Btrfs: add more maintainers
2015-01-09 17:46:07 -08:00
Wang Shilong c7cfb8a540 Btrfs: call inode_dec_link_count() on mkdir error path
In btrfs_mkdir(), if it fails to create dir, we should
clean up existed items, setting inode's link properly
to make sure it could be cleaned up properly.

Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-01-02 14:47:55 -05:00
Linus Torvalds bdeb03cada Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs update from Chris Mason:
 "From a feature point of view, most of the code here comes from Miao
  Xie and others at Fujitsu to implement scrubbing and replacing devices
  on raid56.  This has been in development for a while, and it's a big
  improvement.

  Filipe and Josef have a great assortment of fixes, many of which solve
  problems corruptions either after a crash or in error conditions.  I
  still have a round two from Filipe for next week that solves
  corruptions with discard and block group removal"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits)
  Btrfs: make get_caching_control unconditionally return the ctl
  Btrfs: fix unprotected deletion from pending_chunks list
  Btrfs: fix fs mapping extent map leak
  Btrfs: fix memory leak after block remove + trimming
  Btrfs: make btrfs_abort_transaction consider existence of new block groups
  Btrfs: fix race between writing free space cache and trimming
  Btrfs: fix race between fs trimming and block group remove/allocation
  Btrfs, replace: enable dev-replace for raid56
  Btrfs: fix freeing used extents after removing empty block group
  Btrfs: fix crash caused by block group removal
  Btrfs: fix invalid block group rbtree access after bg is removed
  Btrfs, raid56: fix use-after-free problem in the final device replace procedure on raid56
  Btrfs, replace: write raid56 parity into the replace target device
  Btrfs, replace: write dirty pages into the replace target device
  Btrfs, raid56: support parity scrub on raid56
  Btrfs, raid56: use a variant to record the operation type
  Btrfs, scrub: repair the common data on RAID5/6 if it is corrupted
  Btrfs, raid56: don't change bbio and raid_map
  Btrfs: remove unnecessary code of stripe_index assignment in __btrfs_map_block
  Btrfs: remove noused bbio_ret in __btrfs_map_block in condition
  ...
2014-12-12 11:15:23 -08:00
Filipe Manana 9ea24bbe17 Btrfs: fix snapshot inconsistency after a file write followed by truncate
If right after starting the snapshot creation ioctl we perform a write against a
file followed by a truncate, with both operations increasing the file's size, we
can get a snapshot tree that reflects a state of the source subvolume's tree where
the file truncation happened but the write operation didn't. This leaves a gap
between 2 file extent items of the inode, which makes btrfs' fsck complain about it.

For example, if we perform the following file operations:

    $ mkfs.btrfs -f /dev/vdd
    $ mount /dev/vdd /mnt
    $ xfs_io -f \
          -c "pwrite -S 0xaa -b 32K 0 32K" \
          -c "fsync" \
          -c "pwrite -S 0xbb -b 32770 16K 32770" \
          -c "truncate 90123" \
          /mnt/foobar

and the snapshot creation ioctl was just called before the second write, we often
can get the following inode items in the snapshot's btree:

        item 120 key (257 INODE_ITEM 0) itemoff 7987 itemsize 160
                inode generation 146 transid 7 size 90123 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 flags 0x0
        item 121 key (257 INODE_REF 256) itemoff 7967 itemsize 20
                inode ref index 282 namelen 10 name: foobar
        item 122 key (257 EXTENT_DATA 0) itemoff 7914 itemsize 53
                extent data disk byte 1104855040 nr 32768
                extent data offset 0 nr 32768 ram 32768
                extent compression 0
        item 123 key (257 EXTENT_DATA 53248) itemoff 7861 itemsize 53
                extent data disk byte 0 nr 0
                extent data offset 0 nr 40960 ram 40960
                extent compression 0

There's a file range, corresponding to the interval [32K; ALIGN(16K + 32770, 4096)[
for which there's no file extent item covering it. This is because the file write
and file truncate operations happened both right after the snapshot creation ioctl
called btrfs_start_delalloc_inodes(), which means we didn't start and wait for the
ordered extent that matches the write and, in btrfs_setsize(), we were able to call
btrfs_cont_expand() before being able to commit the current transaction in the
snapshot creation ioctl. So this made it possibe to insert the hole file extent
item in the source subvolume (which represents the region added by the truncate)
right before the transaction commit from the snapshot creation ioctl.

Btrfs' fsck tool complains about such cases with a message like the following:

    "root 331 inode 257 errors 100, file extent discount"

>From a user perspective, the expectation when a snapshot is created while those
file operations are being performed is that the snapshot will have a file that
either:

1) is empty
2) only the first write was captured
3) only the 2 writes were captured
4) both writes and the truncation were captured

But never capture a state where only the first write and the truncation were
captured (since the second write was performed before the truncation).

A test case for xfstests follows.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-25 07:41:23 -08:00
Filipe Manana b38ef71cb1 Btrfs: ensure ordered extent errors aren't missed on fsync
When doing a fsync with a fast path we have a time window where we can miss
the fact that writeback of some file data failed, and therefore we endup
returning success (0) from fsync when we should return an error.
The steps that lead to this are the following:

1) We start all ordered extents by calling filemap_fdatawrite_range();

2) We do some other work like locking the inode's i_mutex, start a transaction,
   start a log transaction, etc;

3) We enter btrfs_log_inode(), acquire the inode's log_mutex and collect all the
   ordered extents from inode's ordered tree into a list;

4) But by the time we do ordered extent collection, some ordered extents we started
   at step 1) might have already completed with an error, and therefore we didn't
   found them in the ordered tree and had no idea they finished with an error. This
   makes our fsync return success (0) to userspace, but has no bad effects on the log
   like for example insertion of file extent items into the log that point to unwritten
   extents, because the invalid extent maps were removed before the ordered extent
   completed (in inode.c:btrfs_finish_ordered_io).

So after collecting the ordered extents just check if the inode's i_mapping has any
error flags set (AS_EIO or AS_ENOSPC) and leave with an error if it does. Whenever
writeback fails for a page of an ordered extent, we call mapping_set_error (done in
extent_io.c:end_extent_writepage, called by extent_io.c:end_bio_extent_writepage)
that sets one of those error flags in the inode's i_mapping flags.

This change also has the side effect of fixing the issue where for fast fsyncs we
never checked/cleared the error flags from the inode's i_mapping flags, which means
that a full fsync performed after a fast fsync could get such errors that belonged
to the fast fsync - because the full fsync calls btrfs_wait_ordered_range() which
calls filemap_fdatawait_range(), and the later checks for and clears those flags,
while for fast fsyncs we never call filemap_fdatawait_range() or anything else
that checks for and clears the error flags from the inode's i_mapping.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-21 11:59:57 -08:00
Filipe Manana e6eb43142a Btrfs: report error after failure inlining extent in compressed write path
If cow_file_range_inline() failed, when called from compress_file_range(),
we were tagging the locked page for writeback, end its writeback and unlock it,
but not marking it with an error nor setting AS_EIO in inode's mapping flags.

This made it impossible for a caller of filemap_fdatawrite_range (writepages)
or filemap_fdatawait_range() to know that an error happened. And the return
value of compress_file_range() is useless because it's returned to a workqueue
task and not to the task calling filemap_fdatawrite_range (writepages).

This change applies on top of the previous patchset starting at the patch
titled:

    "[1/5] Btrfs: set page and mapping error on compressed write failure"

Which changed extent_clear_unlock_delalloc() to use SetPageError and
mapping_set_error().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:28 -08:00
Filipe Manana 728404dacf Btrfs: add helper btrfs_fdatawrite_range
To avoid duplicating this double filemap_fdatawrite_range() call for
inodes with async extents (compressed writes) so often.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:28 -08:00
Filipe Manana 075bdbdbe9 Btrfs: correctly flush compressed data before/after direct IO
For compressed writes, after doing the first filemap_fdatawrite_range() we
don't get the pages tagged for writeback immediately. Instead we create
a workqueue task, which is run by other kthread, and keep the pages locked.
That other kthread compresses data, creates the respective ordered extent/s,
tags the pages for writeback and unlocks them. Therefore we need a second
call to filemap_fdatawrite_range() if we have compressed writes, as this
second call will wait for the pages to become unlocked, then see they became
tagged for writeback and finally wait for the writeback to finish.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:27 -08:00
Filipe Manana c44f649e28 Btrfs: make inode.c:compress_file_range() return void
Its return value is useless, its single caller ignores it and can't do
anything with it anyway, since it's a workqueue task and not the task
calling filemap_fdatawrite_range (writepages) nor filemap_fdatawait_range().
Failure is communicated to such functions via start and end of writeback
with the respective pages tagged with an error and AS_EIO flag set in the
inode's imapping.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:27 -08:00
Shilong Wang 4bcbb33255 Btrfs: fix incorrect compression ratio detection
Steps to reproduce:
 # mkfs.btrfs -f /dev/sdb
 # mount -t btrfs /dev/sdb /mnt -o compress=lzo
 # dd if=/dev/zero of=/mnt/data bs=$((33*4096)) count=1

after previous steps, inode will be detected as bad compression ratio,
and NOCOMPRESS flag will be set for that inode.

Reason is that compress have a max limit pages every time(128K), if a
132k write in, it will be splitted into two write(128k+4k), this bug
is a leftover for commit 68bb462d42a(Btrfs: don't compress for a small write)

Fix this problem by checking every time before compression, if it is a
small write(<=blocksize), we bail out and fall into nocompression directly.

Signed-off-by: Wang Shilong <wangshilong1991@gmail.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:27 -08:00
Filipe Manana dec8f17563 Btrfs: make inode.c:submit_compressed_extents() return void
Its return value is completely ignored by its single caller and it's
useless anyway, since errors are indicated through SetPageError and
the bit AS_EIO set in the flags of the inode's mapping. The caller
can't do anything with the value, as it's invoked from a workqueue
task and not by the task calling filemap_fdatawrite_range (which calls
the writepages address space callback, which in turn calls the inode's
fill_delalloc callback).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:26 -08:00
Filipe Manana 3d7a820f71 Btrfs: process all async extents on compressed write failure
If we had an error when processing one of the async extents from our list,
we were not processing the remaining async extents, meaning we would leak
those async_extent structs, never release the pages with the compressed
data and never unlock and clear the dirty flag from the inode's pages (those
that correspond to the uncompressed content).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:26 -08:00
Filipe Manana 40ae837b43 Btrfs: don't leak pages and memory on compressed write error
In inode.c:submit_compressed_extents(), if we fail before calling
btrfs_submit_compressed_write(), or when that function fails, we
were freeing the async_extent structure without releasing its pages
and freeing the pages array.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:26 -08:00
Filipe Manana fce2a4e6b2 Btrfs: fix hang on compressed write error
In inode.c:submit_compressed_extents(), before calling btrfs_submit_compressed_write()
we start writeback for all pages, clear their dirty flag, unlock them, etc, but if
btrfs_submit_compressed_write() fails (at the moment it can only fail with -ENOMEM),
we never end the writeback on the pages, so any filemap_fdatawait_range() call will
hang forever. We were also not calling the writepage end io hook, which means the
corresponding ordered extent will never complete and all its waiters will block
forever, such as a full fsync (via btrfs_wait_ordered_range()).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:25 -08:00
Filipe Manana 704de49d2b Btrfs: set page and mapping error on compressed write failure
If we fail in submit_compressed_extents() before calling btrfs_submit_compressed_write(),
we start and end the writeback for the pages (clear their dirty flag, unlock them, etc)
but we don't tag the pages, nor the inode's mapping, with an error. This makes it
impossible for a caller of filemap_fdatawait_range() (fsync, or transaction commit
for e.g.) know that there was an error.

Note that the return value of submit_compressed_extents() is useless, as that function
is executed by a workqueue task and not directly by the fill_delalloc callback. This
means the writepage/s callbacks of the inode's address space operations don't get that
return value.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:14:25 -08:00
Al Viro 41d28bca2d switch d_materialise_unique() users to d_splice_alias()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19 13:01:20 -05:00
Chris Mason d37973082b Revert "Btrfs: race free update of commit root for ro snapshots"
This reverts commit 9c3b306e1c.

Switching only one commit root during a transaction is wrong because it
leads the fs into an inconsistent state. All commit roots should be
switched at once, at transaction commit time, otherwise backref walking
can often miss important references that were only accessible through
the old commit root.  Plus, the root item for the snapshot's root wasn't
getting updated and preventing the next transaction commit to do it.

This made several users get into random corruption issues after creation
of readonly snapshots.

A regression test for xfstests will follow soon.

Cc: stable@vger.kernel.org # 3.17
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-10-17 02:40:59 -07:00
Chris Mason 0ec31a61f0 Merge branch 'remove-unlikely' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:44 -07:00
Chris Mason bbf65cf0b5 Merge branch 'cleanup/misc-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus
Signed-off-by: Chris Mason <clm@fb.com>

Conflicts:
	fs/btrfs/extent_io.c
2014-10-04 09:56:45 -07:00
Qu Wenruo 32be3a1ac6 btrfs: Fix the wrong condition judgment about subset extent map
Previous commit: btrfs: Fix and enhance merge_extent_mapping() to insert
best fitted extent map
is using wrong condition to judgement whether the range is a subset of a
existing extent map.

This may cause bug in btrfs no-holes mode.

This patch will correct the judgment and fix the bug.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-10-03 16:14:58 -07:00
David Sterba bfebd8b544 btrfs: use enum for wq endio metadata type
The enum exists but is not consistently used.

Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 17:30:28 +02:00
David Sterba ee39b432b4 btrfs: remove unlikely from data-dependent branches and slow paths
There are the branch hints that obviously depend on the data being
processed, the CPU predictor will do better job according to the actual
load. It also does not make sense to use the hints in slow paths that do
a lot of other operations like locking, waiting or IO.

Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 16:15:21 +02:00
David Sterba 5d99a998f3 btrfs: remove unlikely from NULL checks
Unlikely is implicit for NULL checks of pointers.

Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 16:06:19 +02:00
Josef Bacik 1d52c78afb Btrfs: try not to ENOSPC on log replay
When doing log replay we may have to update inodes, which traditionally goes
through our delayed inode stuff.  This will try to move space over from the
trans handle, but we don't reserve space in our trans handle on replay since we
don't know how much we will need, so instead we try to flush.  But because we
have a trans handle open we won't flush anything, so if we are out of reserve
space we will simply return ENOSPC.  Since we know that if an operation made it
into the log then we definitely had space before the box bought the farm then we
don't need to worry about doing this space reservation.  Use the
fs_info->log_root_recovering flag to skip the delayed inode stuff and update the
item directly.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-22 17:13:36 -07:00
Qu Wenruo e6c4efd87a btrfs: Fix and enhance merge_extent_mapping() to insert best fitted extent map
The following commit enhanced the merge_extent_mapping() to reduce
fragment in extent map tree, but it can't handle case which existing
lies before map_start:
51f39 btrfs: Use right extent length when inserting overlap extent map.

[BUG]
When existing extent map's start is before map_start,
the em->len will be minus, which will corrupt the extent map and fail to
insert the new extent map.
This will happen when someone get a large extent map, but when it is
going to insert it into extent map tree, some one has already commit
some write and split the huge extent into small parts.

[REPRODUCER]
It is very easy to tiger using filebench with randomrw personality.
It is about 100% to reproduce when using 8G preallocated file in 60s
randonrw test.

[FIX]
This patch can now handle any existing extent position.
Since it does not directly use existing->start, now it will find the
previous and next extent around map_start.
So the old existing->start < map_start bug will never happen again.

[ENHANCE]
This patch will insert the best fitted extent map into extent map tree,
other than the oldest [map_start, map_start + sectorsize) or the
relatively newer but not perfect [map_start, existing->start).

The patch will first search existing extent that does not intersects with
the desired map range [map_start, map_start + len).
The existing extent will be either before or behind map_start, and based
on the existing extent, we can find out the previous and next extent
around map_start.

So the best fitted extent would be [prev->end, next->start).
For prev or next is not found, em->start would be prev->end and em->end
wold be next->start.

With this patch, the fragment in extent map tree should be reduced much
more than the 51f39 commit and reduce an unneeded extent map tree search.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-18 07:14:46 -07:00
Miao Xie f612496bca Btrfs: cleanup the read failure record after write or when the inode is freeing
After the data is written successfully, we should cleanup the read failure record
in that range because
- If we set data COW for the file, the range that the failure record pointed to is
  mapped to a new place, so it is invalid.
- If we set no data COW for the file, and if there is no error during writting,
  the corrupted data is corrected, so the failure record can be removed. And if
  some errors happen on the mirrors, we also needn't worry about it because the
  failure record will be recreated if we read the same place again.

Sometimes, we may fail to correct the data, so the failure records will be left
in the tree, we need free them when we free the inode or the memory leak happens.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:39:02 -07:00
Miao Xie 8b110e393c Btrfs: implement repair function when direct read fails
This patch implement data repair function when direct read fails.

The detail of the implementation is:
- When we find the data is not right, we try to read the data from the other
  mirror.
- When the io on the mirror ends, we will insert the endio work into the
  dedicated btrfs workqueue, not common read endio workqueue, because the
  original endio work is still blocked in the btrfs endio workqueue, if we
  insert the endio work of the io on the mirror into that workqueue, deadlock
  would happen.
- After we get right data, we write it back to the corrupted mirror.
- And if the data on the new mirror is still corrupted, we will try next
  mirror until we read right data or all the mirrors are traversed.
- After the above work, we set the uptodate flag according to the result.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:39:01 -07:00
Miao Xie c1dc08967f Btrfs: do file data check by sub-bio's self
Direct IO splits the original bio to several sub-bios because of the limit of
raid stripe, and the filesystem will wait for all sub-bios and then run final
end io process.

But it was very hard to implement the data repair when dio read failure happens,
because at the final end io function, we didn't know which mirror the data was
read from. So in order to implement the data repair, we have to move the file data
check in the final end io function to the sub-bio end io function, in which we can
get the mirror number of the device we access. This patch did this work as the
first step of the direct io data repair implementation.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:53 -07:00
Miao Xie dc380aea5f Btrfs: cleanup similar code of the buffered data data check and dio read data check
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:52 -07:00
Miao Xie 23ea8e5a07 Btrfs: load checksum data once when submitting a direct read io
The current code would load checksum data for several times when we split
a whole direct read io because of the limit of the raid stripe, it would
make us search the csum tree for several times. In fact, it just wasted time,
and made the contention of the csum tree root be more serious. This patch
improves this problem by loading the data at once.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:50 -07:00
Wang Shilong 354877befa Btrfs: fix off-by-one in cow_file_range_inline()
Btrfs could still inline file data if its size is same as
page size, so don't skip max value here.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:39 -07:00
Wang Shilong 7816030eb4 Btrfs: fall into nocompression codes quickly if possible
If flag NOCOMPRESS is set which means bad compression ratio,
we could avoid call cow_file_range_async() for this case earlier.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:38 -07:00
Wang Shilong f79707b092 Btrfs: fix wrong skipping compression for an inode
If a file's compression ratios is bad, we will set NOCOMPRESS
flag for it, and it will skip compression for that inode next time.

However, if we remount fs to COMPRESS_FORCE, it still should try
if we could compress pages for that inode, this patch fix wrong
check for this problem.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:36 -07:00
Filipe Manana 555e128640 Btrfs: set error return value in btrfs_get_blocks_direct
We were returning with 0 (success) because we weren't extracting the
error code from em (PTR_ERR(em)). Fix it.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:32 -07:00
Wang Shilong 47059d930f Btrfs: make defragment work with nodatacow option
Btrfs defragment will utilize COW feature, which means this
did not work for nodatacow option, this problem was detected
by xfstests generic/018 with nodatacow mount option.

Fix this problem by forcing cow for a extent with state
@EXTETN_DEFRAG setting.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:26 -07:00
David Sterba 962a298f35 btrfs: kill the key type accessor helpers
btrfs_set_key_type and btrfs_key_type are used inconsistently along with
open coded variants. Other members of btrfs_key are accessed directly
without any helpers anyway.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:12 -07:00
Linus Torvalds 7ed641be75 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Filipe is doing a careful pass through fsync problems, and these are
  the fixes so far.  I'll have one more for rc6 that we're still
  testing.

  My big commit is fixing up some inode hash races that Al Viro found
  (thanks Al)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: use insert_inode_locked4 for inode creation
  Btrfs: fix fsync data loss after a ranged fsync
  Btrfs: kfree()ing ERR_PTRs
  Btrfs: fix crash while doing a ranged fsync
  Btrfs: fix corruption after write/fsync failure + fsync + log recovery
  Btrfs: fix autodefrag with compression
2014-09-12 11:53:30 -07:00
Chris Mason b0d5d10f41 Btrfs: use insert_inode_locked4 for inode creation
Btrfs was inserting inodes into the hash table before we had fully
set the inode up on disk.  This leaves us open to rare races that allow
two different inodes in memory for the same [root, inode] pair.

This patch fixes things by using insert_inode_locked4 to insert an I_NEW
inode and unlock_new_inode when we're ready for the rest of the kernel
to use the inode.

It also makes sure to init the operations pointers on the inode before
going into the error handling paths.

Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
2014-09-08 13:56:45 -07:00
Filipe Manana dac5705cad Btrfs: fix crash while doing a ranged fsync
While doing a ranged fsync, that is, one whose range doesn't cover the
whole possible file range (0 to LLONG_MAX), we can crash under certain
circumstances with a trace like the following:

[41074.641913] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
(...)
[41074.642692] CPU: 0 PID: 24580 Comm: fsx Not tainted 3.16.0-fdm-btrfs-next-45+ #1
(...)
[41074.643886] RIP: 0010:[<ffffffffa01ecc99>]  [<ffffffffa01ecc99>] btrfs_ordered_update_i_size+0x279/0x2b0 [btrfs]
(...)
[41074.644919] Stack:
(...)
[41074.644919] Call Trace:
[41074.644919]  [<ffffffffa01db531>] btrfs_truncate_inode_items+0x3f1/0xa10 [btrfs]
[41074.644919]  [<ffffffffa01eb54f>] ? btrfs_get_logged_extents+0x4f/0x80 [btrfs]
[41074.644919]  [<ffffffffa02137a9>] btrfs_log_inode+0x2f9/0x970 [btrfs]
[41074.644919]  [<ffffffff81090875>] ? sched_clock_local+0x25/0xa0
[41074.644919]  [<ffffffff8164a55e>] ? mutex_unlock+0xe/0x10
[41074.644919]  [<ffffffff810af51d>] ? trace_hardirqs_on+0xd/0x10
[41074.644919]  [<ffffffffa0214b4f>] btrfs_log_inode_parent+0x1ef/0x560 [btrfs]
[41074.644919]  [<ffffffff811d0c55>] ? dget_parent+0x5/0x180
[41074.644919]  [<ffffffffa0215d11>] btrfs_log_dentry_safe+0x51/0x80 [btrfs]
[41074.644919]  [<ffffffffa01e2d1a>] btrfs_sync_file+0x1ba/0x3e0 [btrfs]
[41074.644919]  [<ffffffff811eda6b>] vfs_fsync_range+0x1b/0x30
(...)

The necessary conditions that lead to such crash are:

* an incremental fsync (when the inode doesn't have the
  BTRFS_INODE_NEEDS_FULL_SYNC flag set) happened for our file and it logged
  a file extent item ending at offset X;

* the file got the flag BTRFS_INODE_NEEDS_FULL_SYNC set in its inode, due
  to a file truncate operation that reduces the file to a size smaller
  than X;

* a ranged fsync call happens (via an msync for example), with a range that
  doesn't cover the whole file and the end of this range, lets call it Y, is
  smaller than X;

* btrfs_log_inode, sees the flag BTRFS_INODE_NEEDS_FULL_SYNC set and
  calls btrfs_truncate_inode_items() to remove all items from the log
  tree that are associated with our file;

* btrfs_truncate_inode_items() removes all of the inode's items, and the lowest
  file extent item it removed is the one ending at offset X, where X > 0 and
  X > Y - before returning, it calls btrfs_ordered_update_i_size() with an offset
  parameter set to X;

* btrfs_ordered_update_i_size() sees that X is greater then the current ordered
  size (btrfs_inode's disk_i_size) and then it assumes there can't be any ongoing
  ordered operation with a range covering the offset X, calling a BUG_ON() if
  such ordered operation exists. This assumption is made because the disk_i_size
  is only increased after the corresponding file extent item is added to the
  btree (btrfs_finish_ordered_io);

* But because our fsync covers only a limited range, such an ordered extent might
  exist, and our fsync callback (btrfs_sync_file) doesn't wait for such ordered
  extent to finish when calling btrfs_wait_ordered_range();

And then by the time btrfs_ordered_update_i_size() is called, via:

   btrfs_sync_file() ->
       btrfs_log_dentry_safe() ->
           btrfs_log_inode_parent() ->
               btrfs_log_inode() ->
                   btrfs_truncate_inode_items() ->
                       btrfs_ordered_update_i_size()

We hit the BUG_ON(), which could never happen if the fsync range covered the whole
possible file range (0 to LLONG_MAX), as we would wait for all ordered extents to
finish before calling btrfs_truncate_inode_items().

So just don't call btrfs_ordered_update_i_size() if we're removing the inode's items
from a log tree, which isn't supposed to change the in memory inode's disk_i_size.

Issue found while running xfstests/generic/127 (happens very rarely for me), more
specifically via the fsx calls that use memory mapped IO (and issue msync calls).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-02 16:46:05 -07:00
Filipe Manana d9f85963e3 Btrfs: fix corruption after write/fsync failure + fsync + log recovery
While writing to a file, in inode.c:cow_file_range() (and same applies to
submit_compressed_extents()), after reserving an extent for the file data,
we create a new extent map for the written range and insert it into the
extent map cache. After that, we create an ordered operation, but if it
fails (due to a transient/temporary-ENOMEM), we return without dropping
that extent map, which points to a reserved extent that is freed when we
return. A subsequent incremental fsync (when the btrfs inode doesn't have
the flag BTRFS_INODE_NEEDS_FULL_SYNC) considers this extent map valid and
logs a file extent item based on that extent map, which points to a disk
extent that doesn't contain valid data - it was freed by us earlier, at this
point it might contain any random/garbage data.

Therefore, if we reach an error condition when cowing a file range after
we added the new extent map to the cache, drop it from the cache before
returning.

Some sequence of steps that lead to this:

    $ mkfs.btrfs -f /dev/sdd
    $ mount -o commit=9999 /dev/sdd /mnt
    $ cd /mnt

    $ xfs_io -f -c "pwrite -S 0x01 -b 4096 0 4096" -c "fsync" foo
    $ xfs_io -c "pwrite -S 0x02 -b 4096 4096 4096"
    $ sync

    $ od -t x1 foo
    0000000 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01
    *
    0010000 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02
    *
    0020000

    $ xfs_io -c "pwrite -S 0xa1 -b 4096 0 4096" foo

    # Now this write + fsync fail with -ENOMEM, which was returned by
    # btrfs_add_ordered_extent() in inode.c:cow_file_range().
    $ xfs_io -c "pwrite -S 0xff -b 4096 4096 4096" foo
    $ xfs_io -c "fsync" foo
    fsync: Cannot allocate memory

    # Now do a new write + fsync, which will succeed. Our previous
    # -ENOMEM was a transient/temporary error.
    $ xfs_io -c "pwrite -S 0xee -b 4096 16384 4096" foo
    $ xfs_io -c "fsync" foo

    # Our file content (in page cache) is now:
    $ od -t x1 foo
    0000000 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1
    *
    0010000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
    *
    0020000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    *
    0040000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
    *
    0050000

    # Now reboot the machine, and mount the fs, so that fsync log replay
    # takes place.

    # The file content is now weird, in particular the first 8Kb, which
    # do not match our data before nor after the sync command above.
    $ od -t x1 foo
    0000000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
    *
    0010000 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01
    *
    0020000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    *
    0040000 ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee ee
    *
    0050000

    # In fact these first 4Kb are a duplicate of the last 4kb block.
    # The last write got an extent map/file extent item that points to
    # the same disk extent that we got in the write+fsync that failed
    # with the -ENOMEM error. btrfs-debug-tree and btrfsck allow us to
    # verify that:

    $ btrfs-debug-tree /dev/sdd
    (...)
	item 6 key (257 EXTENT_DATA 0) itemoff 15819 itemsize 53
		extent data disk byte 12582912 nr 8192
		extent data offset 0 nr 8192 ram 8192
	item 7 key (257 EXTENT_DATA 8192) itemoff 15766 itemsize 53
		extent data disk byte 0 nr 0
		extent data offset 0 nr 8192 ram 8192
	item 8 key (257 EXTENT_DATA 16384) itemoff 15713 itemsize 53
		extent data disk byte 12582912 nr 4096
		extent data offset 0 nr 4096 ram 4096

    $ umount /dev/sdd
    $ btrfsck /dev/sdd
    Checking filesystem on /dev/sdd
    UUID: db5e60e1-050d-41e6-8c7f-3d742dea5d8f
    checking extents
    extent item 12582912 has multiple extent items
    ref mismatch on [12582912 4096] extent item 1, found 2
    Backref bytes do not match extent backref, bytenr=12582912, ref bytes=4096, backref bytes=8192
    backpointer mismatch on [12582912 4096]
    Errors found in extent allocation tree or chunk allocation
    checking free space cache
    checking fs roots
    root 5 inode 257 errors 1000, some csum missing
    found 131074 bytes used err is 1
    total csum bytes: 4
    total tree bytes: 131072
    total fs tree bytes: 32768
    total extent tree bytes: 16384
    btree space waste bytes: 123404
    file data blocks allocated: 274432
     referenced 274432
    Btrfs v3.14.1-96-gcc7fd5a-dirty

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-02 16:46:05 -07:00
Linus Torvalds 1fb00cbca0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "The biggest of these comes from Liu Bo, who tracked down a hang we've
  been hitting since moving to kernel workqueues (it's a btrfs bug, not
  in the generic code).  His patch needs backporting to 3.16 and 3.15
  stable, which I'll send once this is in.

  Otherwise these are assorted fixes.  Most were integrated last week
  during KS, but I wanted to give everyone the chance to test the
  result, so I waited for rc2 to come out before sending"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
  Btrfs: fix task hang under heavy compressed write
  Btrfs: fix filemap_flush call in btrfs_file_release
  Btrfs: fix crash on endio of reading corrupted block
  btrfs: fix leak in qgroup_subtree_accounting() error path
  btrfs: Use right extent length when inserting overlap extent map.
  Btrfs: clone, don't create invalid hole extent map
  Btrfs: don't monopolize a core when evicting inode
  Btrfs: fix hole detection during file fsync
  Btrfs: ensure tmpfile inode is always persisted with link count of 0
  Btrfs: race free update of commit root for ro snapshots
  Btrfs: fix regression of btrfs device replace
  Btrfs: don't consider the missing device when allocating new chunks
  Btrfs: Fix wrong device size when we are resizing the device
  Btrfs: don't write any data into a readonly device when scrub
  Btrfs: Fix the problem that the replace destroys the seed filesystem
  btrfs: Return right extent when fiemap gives unaligned offset and len.
  Btrfs: fix wrong extent mapping for DirectIO
  Btrfs: fix wrong write range for filemap_fdatawrite_range()
  Btrfs: fix wrong missing device counter decrease
  Btrfs: fix unzeroed members in fs_devices when creating a fs from seed fs
  ...
2014-08-27 09:14:17 -07:00
Liu Bo 9e0af23764 Btrfs: fix task hang under heavy compressed write
This has been reported and discussed for a long time, and this hang occurs in
both 3.15 and 3.16.

Btrfs now migrates to use kernel workqueue, but it introduces this hang problem.

Btrfs has a kind of work queued as an ordered way, which means that its
ordered_func() must be processed in the way of FIFO, so it usually looks like --

normal_work_helper(arg)
    work = container_of(arg, struct btrfs_work, normal_work);

    work->func() <---- (we name it work X)
    for ordered_work in wq->ordered_list
            ordered_work->ordered_func()
            ordered_work->ordered_free()

The hang is a rare case, first when we find free space, we get an uncached block
group, then we go to read its free space cache inode for free space information,
so it will

file a readahead request
    btrfs_readpages()
         for page that is not in page cache
                __do_readpage()
                     submit_extent_page()
                           btrfs_submit_bio_hook()
                                 btrfs_bio_wq_end_io()
                                 submit_bio()
                                 end_workqueue_bio() <--(ret by the 1st endio)
                                      queue a work(named work Y) for the 2nd
                                      also the real endio()

So the hang occurs when work Y's work_struct and work X's work_struct happens
to share the same address.

A bit more explanation,

A,B,C -- struct btrfs_work
arg   -- struct work_struct

kthread:
worker_thread()
    pick up a work_struct from @worklist
    process_one_work(arg)
	worker->current_work = arg;  <-- arg is A->normal_work
	worker->current_func(arg)
		normal_work_helper(arg)
		     A = container_of(arg, struct btrfs_work, normal_work);

		     A->func()
		     A->ordered_func()
		     A->ordered_free()  <-- A gets freed

		     B->ordered_func()
			  submit_compressed_extents()
			      find_free_extent()
				  load_free_space_inode()
				      ...   <-- (the above readhead stack)
				      end_workqueue_bio()
					   btrfs_queue_work(work C)
		     B->ordered_free()

As if work A has a high priority in wq->ordered_list and there are more ordered
works queued after it, such as B->ordered_func(), its memory could have been
freed before normal_work_helper() returns, which means that kernel workqueue
code worker_thread() still has worker->current_work pointer to be work
A->normal_work's, ie. arg's address.

Meanwhile, work C is allocated after work A is freed, work C->normal_work
and work A->normal_work are likely to share the same address(I confirmed this
with ftrace output, so I'm not just guessing, it's rare though).

When another kthread picks up work C->normal_work to process, and finds our
kthread is processing it(see find_worker_executing_work()), it'll think
work C as a collision and skip then, which ends up nobody processing work C.

So the situation is that our kthread is waiting forever on work C.

Besides, there're other cases that can lead to deadlock, but the real problem
is that all btrfs workqueue shares one work->func, -- normal_work_helper,
so this makes each workqueue to have its own helper function, but only a
wraper pf normal_work_helper.

With this patch, I no long hit the above hang.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-24 07:17:02 -07:00
Qu Wenruo 51f395ad40 btrfs: Use right extent length when inserting overlap extent map.
When current btrfs finds that a new extent map is going to be insereted
but failed with -EEXIST, it will try again to insert the extent map
but with the length of sectorsize.
This is OK if we don't enable 'no-holes' feature since all extent space
is continuous, we will not go into the not found->insert routine.

But if we enable 'no-holes' feature, it will make things out of control.
e.g. in 4K sectorsize, we pass the following args to btrfs_get_extent():
btrfs_get_extent() args: start:  27874 len 4100
28672		  27874		28672	27874+4100	32768
                    |-----------------------|
|---------hole--------------------|---------data----------|

1) not found and insert
Since no extent map containing the range, btrfs_get_extent() will go
into the not_found and insert routine, which will try to insert the
extent map (27874, 27847 + 4100).

2) first overlap
But it overlaps with (28672, 32768) extent, so -EEXIST will be returned
by add_extent_mapping().

3) retry but still overlap
After catching the -EEXIST, then btrfs_get_extent() will try insert it
again but with 4K length, which still overlaps, so -EEXIST will be
returned.

This makes the following patch fail to punch hole.
d77815461f btrfs: Avoid trucating page or punching hole in a already existed hole.

This patch will use the right length, which is the (exsisting->start -
em->start) to insert, making the above patch works in 'no-holes' mode.
Also, some small code style problems in above patch is fixed too.

Reported-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe David Manana <fdmanana@suse.com>
Tested-by: Filipe David Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:27 -07:00
Filipe Manana 7064dd5c36 Btrfs: don't monopolize a core when evicting inode
If an inode has a very large number of extent maps, we can spend
a lot of time freeing them, which triggers a soft lockup warning.
Therefore reschedule if we need to when freeing the extent maps
while evicting the inode.

I could trigger this all the time by running xfstests/generic/299 on
a file system with the no-holes feature enabled. That test creates
an inode with 11386677 extent maps.

    $ mkfs.btrfs -f -O no-holes $TEST_DEV
    $ MKFS_OPTIONS="-O no-holes" ./check generic/299
    generic/299 382s ...
    Message from syslogd@debian-vm3 at Aug  7 10:44:29 ...
     kernel:[85304.208017] BUG: soft lockup - CPU#0 stuck for 22s! [umount:25330]
     384s
    Ran: generic/299
    Passed all 1 tests

    $ dmesg
    (...)
    [86304.300017] BUG: soft lockup - CPU#0 stuck for 23s! [umount:25330]
    (...)
    [86304.300036] Call Trace:
    [86304.300036]  [<ffffffff81698ba9>] __slab_free+0x54/0x295
    [86304.300036]  [<ffffffffa02ee9cc>] ? free_extent_map+0x5c/0xb0 [btrfs]
    [86304.300036]  [<ffffffff811a6cd2>] kmem_cache_free+0x282/0x2a0
    [86304.300036]  [<ffffffffa02ee9cc>] free_extent_map+0x5c/0xb0 [btrfs]
    [86304.300036]  [<ffffffffa02e3775>] btrfs_evict_inode+0xd5/0x660 [btrfs]
    [86304.300036]  [<ffffffff811e7c8d>] ? __inode_wait_for_writeback+0x6d/0xc0
    [86304.300036]  [<ffffffff816a389b>] ? _raw_spin_unlock+0x2b/0x40
    [86304.300036]  [<ffffffff811d8cbb>] evict+0xab/0x180
    [86304.300036]  [<ffffffff811d8dce>] dispose_list+0x3e/0x60
    [86304.300036]  [<ffffffff811d9b04>] evict_inodes+0xf4/0x110
    [86304.300036]  [<ffffffff811bd953>] generic_shutdown_super+0x53/0x110
    [86304.300036]  [<ffffffff811bdaa6>] kill_anon_super+0x16/0x30
    [86304.300036]  [<ffffffffa02a78ba>] btrfs_kill_super+0x1a/0xa0 [btrfs]
    [86304.300036]  [<ffffffff811bd3a9>] deactivate_locked_super+0x59/0x80
    [86304.300036]  [<ffffffff811be44e>] deactivate_super+0x4e/0x70
    [86304.300036]  [<ffffffff811dec14>] mntput_no_expire+0x174/0x1f0
    [86304.300036]  [<ffffffff811deab7>] ? mntput_no_expire+0x17/0x1f0
    [86304.300036]  [<ffffffff811e0517>] SyS_umount+0x97/0x100
    (...)

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Tested-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:25 -07:00
Filipe Manana 5762b5c958 Btrfs: ensure tmpfile inode is always persisted with link count of 0
If we open a file with O_TMPFILE, don't do any further operation on
it (so that the inode item isn't updated) and then force a transaction
commit, we get a persisted inode item with a link count of 1, and not 0
as it should be.

Steps to reproduce it (requires a modern xfs_io with -T support):

    $ mkfs.btrfs -f /dev/sdd
    $ mount -o /dev/sdd /mnt
    $ xfs_io -T /mnt &
    $ sync

Then btrfs-debug-tree shows the inode item with a link count of 1:

    $ btrfs-debug-tree /dev/sdd
    (...)
    fs tree key (FS_TREE ROOT_ITEM 0)
    leaf 29556736 items 4 free space 15851 generation 6 owner 5
    fs uuid f164d01b-1b92-481d-a4e4-435fb0f843d0
    chunk uuid 0e3d0e56-bcca-4a1c-aa5f-cec2c6f4f7a6
    	item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160
		inode generation 3 transid 6 size 0 block group 0 mode 40755 links 1
    	item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12
    		inode ref index 0 namelen 2 name: ..
    	item 2 key (257 INODE_ITEM 0) itemoff 15951 itemsize 160
    		inode generation 6 transid 6 size 0 block group 0 mode 100600 links 1
    	item 3 key (ORPHAN ORPHAN_ITEM 257) itemoff 15951 itemsize 0
		orphan item
    checksum tree key (CSUM_TREE ROOT_ITEM 0)
    (...)

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:23 -07:00
Filipe Manana 9c3b306e1c Btrfs: race free update of commit root for ro snapshots
This is a better solution for the problem addressed in the following
commit:

    Btrfs: update commit root on snapshot creation after orphan cleanup
    (3821f34888)

The previous solution wasn't the best because of 2 reasons:

    1) It added another full transaction commit, which is more expensive
       than just swapping the commit root with the root;

    2) If a reboot happened after the first transaction commit (the one
       that creates the snapshot) and before the second transaction commit,
       then we would end up with the same problem if a send using that
       snapshot was requested before the first transaction commit after
       the reboot.

This change addresses those 2 issues. The second issue is addressed by
switching the commit root in the dentry lookup VFS callback, which is
also called by the snapshot/subvol creation ioctl and performs orphan
cleanup if needed. Like the vfs, the ioctl locks the parent inode too,
preventing race issues between a dentry lookup and snapshot creation.

Cc: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:21 -07:00
Wang Shilong e2eca69dc6 Btrfs: fix wrong extent mapping for DirectIO
btrfs_next_leaf() will use current leaf's last key to search
and then return a bigger one. So it may still return a file extent
item that is smaller than expected value and we will
get an overflow here for @em->len.

This is easy to reproduce for Btrfs Direct writting, it did not
cause any problem, because writting will re-insert right mapping later.

However, by hacking code to make DIO support compression, wrong extent
mapping is kept and it encounter merging failure(EEXIST) quickly.

Fix this problem by looping to find next file extent item that is bigger
than @start or we could not find anything more.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-19 08:52:13 -07:00
Wang Shilong 9a025a0860 Btrfs: fix wrong write range for filemap_fdatawrite_range()
filemap_fdatawrite_range() expect the third arg to be @end
not @len, fix it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-19 08:52:12 -07:00
Miao Xie 7a5c3c9be1 Btrfs: fix put dio bio twice when we submit dio bio fail
The caller of btrfs_submit_direct_hook() will put the original dio bio
when btrfs_submit_direct_hook() return a error number, so we needn't
put the original bio in btrfs_submit_direct_hook().

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-19 08:36:24 -07:00
Linus Torvalds e64df3ebe8 Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "These are all fixes I'd like to get out to a broader audience.

  The biggest of the bunch is Mark's quota fix, which is also in the
  SUSE kernel, and makes our subvolume quotas dramatically more
  accurate.

  I've been running xfstests with these against your current git
  overnight, but I'm queueing up longer tests as well"

* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: disable strict file flushes for renames and truncates
  Btrfs: fix csum tree corruption, duplicate and outdated checksums
  Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch
  Btrfs: fix compressed write corruption on enospc
  btrfs: correctly handle return from ulist_add
  btrfs: qgroup: account shared subtrees during snapshot delete
  Btrfs: read lock extent buffer while walking backrefs
  Btrfs: __btrfs_mod_ref should always use no_quota
  btrfs: adjust statfs calculations according to raid profiles
2014-08-16 09:06:55 -06:00
Chris Mason 8d875f95da btrfs: disable strict file flushes for renames and truncates
Truncates and renames are often used to replace old versions of a file
with new versions.  Applications often expect this to be an atomic
replacement, even if they haven't done anything to make sure the new
version is fully on disk.

Btrfs has strict flushing in place to make sure that renaming over an
old file with a new file will fully flush out the new file before
allowing the transaction commit with the rename to complete.

This ordering means the commit code needs to be able to lock file pages,
and there are a few paths in the filesystem where we will try to end a
transaction with the page lock held.  It's rare, but these things can
deadlock.

This patch removes the ordered flushes and switches to a best effort
filemap_flush like ext4 uses. It's not perfect, but it should fix the
deadlocks.

Signed-off-by: Chris Mason <clm@fb.com>
2014-08-15 07:43:42 -07:00
Liu Bo ce62003f69 Btrfs: fix compressed write corruption on enospc
When failing to allocate space for the whole compressed extent, we'll
fallback to uncompressed IO, but we've forgotten to redirty the pages
which belong to this compressed extent, and these 'clean' pages will
simply skip 'submit' part and go to endio directly, at last we got data
corruption as we write nothing.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Tested-By: Martin Steigerwald <martin@lichtvoll.de>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-15 07:43:18 -07:00
Miklos Szeredi 80ace85c91 btrfs: add RENAME_NOREPLACE
RENAME_NOREPLACE is trivial to implement for most filesystems: switch over
to ->rename2() and check for the supported flags.  The rest is done by the
VFS.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Chris Mason <clm@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-07 14:40:09 -04:00
Linus Torvalds e13d100beb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This fixes some lockups in btrfs reported with rc1.  It probably has
  some performance impact because it is backing off our spinning locks
  more often and switching to a blocking lock.  I'll be able to nail
  that down next week, but for now I want to get the lockups taken care
  of.

  Otherwise some more stack reduction and assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix wrong error handle when the device is missing or is not writeable
  Btrfs: fix deadlock when mounting a degraded fs
  Btrfs: use bio_endio_nodec instead of open code
  Btrfs: fix NULL pointer crash when running balance and scrub concurrently
  btrfs: Skip scrubbing removed chunks to avoid -ENOENT.
  Btrfs: fix broken free space cache after the system crashed
  Btrfs: make free space cache write out functions more readable
  Btrfs: remove unused wait queue in struct extent_buffer
  Btrfs: fix deadlocks with trylock on tree nodes
2014-06-21 14:21:43 -10:00
Miao Xie e570fd27f2 Btrfs: fix broken free space cache after the system crashed
When we mounted the filesystem after the crash, we got the following
message:
  BTRFS error (device xxx): block group xxxx has wrong amount of free space
  BTRFS error (device xxx): failed to load free space cache for block group xxx

It is because we didn't update the metadata of the allocated space (in extent
tree) until the file data was written into the disk. During this time, there was
no information about the allocated spaces in either the extent tree nor the
free space cache. when we wrote out the free space cache at this time (commit
transaction), those spaces were lost. In fact, only the free space that is
used to store the file data had this problem, the others didn't because
the metadata of them is updated in the same transaction context.

There are many methods which can fix the above problem
- track the allocated space, and write it out when we write out the free
  space cache
- account the size of the allocated space that is used to store the file
  data, if the size is not zero, don't write out the free space cache.

The first one is complex and may make the performance drop down.
This patch chose the second method, we use a per-block-group variant to
account the size of that allocated space. Besides that, we also introduce
a per-block-group read-write semaphore to avoid the race between
the allocation and the free space cache write out.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-19 14:20:54 -07:00
Linus Torvalds 16b9057804 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...
2014-06-12 10:30:18 -07:00
Linus Torvalds 859862ddd2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "The biggest change here is Josef's rework of the btrfs quota
  accounting, which improves the in-memory tracking of delayed extent
  operations.

  I had been working on Btrfs stack usage for a while, mostly because it
  had become impossible to do long stress runs with slab, lockdep and
  pagealloc debugging turned on without blowing the stack.  Even though
  you upgraded us to a nice king sized stack, I kept most of the
  patches.

  We also have some very hard to find corruption fixes, an awesome sysfs
  use after free, and the usual assortment of optimizations, cleanups
  and other fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (80 commits)
  Btrfs: convert smp_mb__{before,after}_clear_bit
  Btrfs: fix scrub_print_warning to handle skinny metadata extents
  Btrfs: make fsync work after cloning into a file
  Btrfs: use right type to get real comparison
  Btrfs: don't check nodes for extent items
  Btrfs: don't release invalid page in btrfs_page_exists_in_range()
  Btrfs: make sure we retry if page is a retriable exception
  Btrfs: make sure we retry if we couldn't get the page
  btrfs: replace EINVAL with EOPNOTSUPP for dev_replace raid56
  trivial: fs/btrfs/ioctl.c: fix typo s/substract/subtract/
  Btrfs: fix leaf corruption after __btrfs_drop_extents
  Btrfs: ensure btrfs_prev_leaf doesn't miss 1 item
  Btrfs: fix clone to deal with holes when NO_HOLES feature is enabled
  btrfs: free delayed node outside of root->inode_lock
  btrfs: replace EINVAL with ERANGE for resize when ULLONG_MAX
  Btrfs: fix transaction leak during fsync call
  btrfs: Avoid trucating page or punching hole in a already existed hole.
  Btrfs: update commit root on snapshot creation after orphan cleanup
  Btrfs: ioctl, don't re-lock extent range when not necessary
  Btrfs: avoid visiting all extent items when cloning a range
  ...
2014-06-11 09:22:21 -07:00
Filipe Manana 7ffbb598a0 Btrfs: make fsync work after cloning into a file
When cloning into a file, we were correctly replacing the extent
items in the target range and removing the extent maps. However
we weren't replacing the extent maps with new ones that point to
the new extents - as a consequence, an incremental fsync (when the
inode doesn't have the full sync flag) was a NOOP, since it relies
on the existence of extent maps in the modified list of the inode's
extent map tree, which was empty. Therefore add new extent maps to
reflect the target clone range.

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:16 -07:00
Filipe Manana 6fdef6d43c Btrfs: don't release invalid page in btrfs_page_exists_in_range()
In inode.c:btrfs_page_exists_in_range(), if the page we got from
the radix tree is an exception entry, which can't be retried, we
exit the loop with a non-NULL page and then call page_cache_release
against it, which is not ok since it's not a valid page. This could
also make us return true when we shouldn't.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:14 -07:00
Filipe Manana 809f901625 Btrfs: make sure we retry if page is a retriable exception
In inode.c:btrfs_page_exists_in_range(), if the page we get from the
radix tree is an exception which should make us retry, set page to
NULL in order to really retry, because otherwise we don't get another
loop iteration executed (page != NULL makes the while loop exit).
This also was making us call page_cache_release after exiting the loop,
which isn't correct because page doesn't point to a valid page, and
possibly return true from the function when we shouldn't.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:13 -07:00
Filipe Manana 91405151eb Btrfs: make sure we retry if we couldn't get the page
In inode.c:btrfs_page_exists_in_range(), if we can't get the page
we need to retry. However we weren't retrying because we weren't
setting page to NULL, which makes the while loop exit immediately
and will make us call page_cache_release after exiting the loop
which is incorrect because our page get didn't succeed. This could
also make us return true when we shouldn't.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:12 -07:00
Chris Mason a79b7d4b3e Btrfs: async delayed refs
Delayed extent operations are triggered during transaction commits.
The goal is to queue up a healthly batch of changes to the extent
allocation tree and run through them in bulk.

This farms them off to async helper threads.  The goal is to have the
bulk of the delayed operations being done in the background, but this is
also important to limit our stack footprint.

Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:58 -07:00
Chris Mason 40f765805f Btrfs: split up __extent_writepage to lower stack usage
__extent_writepage has two unrelated parts.  First it does the delayed
allocation dance and second it does the mapping and IO for the page
we're actually writing.

This splits it up into those two parts so the stack from one doesn't
impact the stack from the other.

Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:58 -07:00
Alex Gartrell fc4adbff82 btrfs: Drop EXTENT_UPTODATE check in hole punching and direct locking
In these instances, we are trying to determine if a page has been accessed
since we began the operation for the sake of retry.  This is easily
accomplished by doing a gang lookup in the page mapping radix tree, and it
saves us the dependency on the flag (so that we might eventually delete
it).

btrfs_page_exists_in_range borrows heavily from find_get_page, replacing
the radix tree look up with a gang lookup of 1, so that we can find the
next highest page >= index and see if it falls into our lock range.

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Alex Gartrell <agartrell@fb.com>
2014-06-09 17:20:57 -07:00
David Sterba 351fd35321 btrfs: remove stale newlines from log messages
I've noticed an extra line after "use no compression", but search
revealed much more in messages of more critical levels and rare errors.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:53 -07:00
Miao Xie 995946dd29 Btrfs: use helpers for last_trans_log_full_commit instead of opencode
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:45 -07:00
Miao Xie 27cdeb7096 Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:40 -07:00
Daeseok Youn 944a4515b2 btrfs: remove redundant null check in btrfs_dentry_release()
It doesn't need to check NULL for kfree()

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:31 -07:00
Filipe Manana ef3b9af50b Btrfs: implement inode_operations callback tmpfile
This implements the tmpfile callback of struct inode_operations, introduced
in the linux kernel 3.11, and implemented already by some filesystems. This
callback is invoked by the VFS when the flag O_TMPFILE is passed to the open
system call.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
2014-06-09 17:20:30 -07:00
Zach Brown 166ae5a418 btrfs: fix inline compressed read err corruption
uncompress_inline() is dropping the error from btrfs_decompress() after
testing it and zeroing the page that was supposed to hold decompressed
data.  This can silently turn compressed inline data in to zeros if
decompression fails due to corrupt compressed data or memory allocation
failure.

I verified this by manually forcing the error from btrfs_decompress()
for a silly named copy of od:

	if (!strcmp(current->comm, "failod"))
		ret = -ENOMEM;

  # od -x /mnt/btrfs/dir/80 | head -1
  0000000 3031 3038 310a 2d30 6f70 6e69 0a74 3031
  # echo 3 > /proc/sys/vm/drop_caches
  # cp $(which od) /tmp/failod
  # /tmp/failod -x /mnt/btrfs/dir/80 | head -1
  0000000 0000 0000 0000 0000 0000 0000 0000 0000

The fix is to pass the error to its caller.  Which still has a BUG_ON().
So we fix that too.

There seems to be no reason for the zeroing of the page on the error
from btrfs_decompress() but not from the allocation error a few lines
above.  So the page zeroing is removed.

Signed-off-by: Zach Brown <zab@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:23 -07:00
Al Viro 28060d5d9b btrfs: switch check_direct_IO() to iov_iter
... and don't open-code iov_iter_alignment() there

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:53 -04:00
Al Viro 31b140398c switch {__,}blockdev_direct_IO() to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:46 -04:00
Al Viro a6cbcd4a4a get rid of pointless iov_length() in ->direct_IO()
all callers have iov_length(iter->iov, iter->nr_segs) == iov_iter_count(iter)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:45 -04:00
Al Viro d8d3d94b80 pass iov_iter to ->direct_IO()
unmodified, for now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:44 -04:00
Peter Zijlstra 4e857c58ef arch: Mass conversion of smp_mb__*()
Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18 14:20:48 +02:00
Linus Torvalds 3123bca719 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull second set of btrfs updates from Chris Mason:
 "The most important changes here are from Josef, fixing a btrfs
  regression in 3.14 that can cause corruptions in the extent allocation
  tree when snapshots are in use.

  Josef also fixed some deadlocks in send/recv and other assorted races
  when balance is running"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (23 commits)
  Btrfs: fix compile warnings on on avr32 platform
  btrfs: allow mounting btrfs subvolumes with different ro/rw options
  btrfs: export global block reserve size as space_info
  btrfs: fix crash in remount(thread_pool=) case
  Btrfs: abort the transaction when we don't find our extent ref
  Btrfs: fix EINVAL checks in btrfs_clone
  Btrfs: fix unlock in __start_delalloc_inodes()
  Btrfs: scrub raid56 stripes in the right way
  Btrfs: don't compress for a small write
  Btrfs: more efficient io tree navigation on wait_extent_bit
  Btrfs: send, build path string only once in send_hole
  btrfs: filter invalid arg for btrfs resize
  Btrfs: send, fix data corruption due to incorrect hole detection
  Btrfs: kmalloc() doesn't return an ERR_PTR
  Btrfs: fix snapshot vs nocow writting
  btrfs: Change the expanding write sequence to fix snapshot related bug.
  btrfs: make device scan less noisy
  btrfs: fix lockdep warning with reclaim lock inversion
  Btrfs: hold the commit_root_sem when getting the commit root during send
  Btrfs: remove transaction from send
  ...
2014-04-11 14:16:53 -07:00
Wang Shilong a1ecaabbf9 Btrfs: fix unlock in __start_delalloc_inodes()
This patch fix a regression caused by the following patch:
Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock

break while loop will make us call @spin_unlock() without
calling @spin_lock() before, fix it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:50 -07:00
Wang Shilong 68bb462d42 Btrfs: don't compress for a small write
To compress a small file range(<=blocksize) that is not
an inline extent can not save disk space at all. skip it can
save us some cpu time.

This patch can also fix wrong setting nocompression flag for
inode, say a case when @total_in is 4096, and then we get
@total_compressed 52,because we do aligment to page cache size
firstly, and then we get into conclusion @total_in=@total_compressed
thus we will clear this inode's compression flag.

An exception comes from inserting inline extent failure but we
still have @total_compressed < @total_in,so we will still reset
inode's flag, this is ok, because we don't have good compression
effect.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:48 -07:00
Wang Shilong e9894fd3e3 Btrfs: fix snapshot vs nocow writting
While running fsstress and snapshots concurrently, we will hit something
like followings:

Thread 1			Thread 2

|->fallocate
  |->write pages
    |->join transaction
       |->add ordered extent
    |->end transaction
				|->flushing data
				  |->creating pending snapshots
|->write data into src root's
   fallocated space

After above work flows finished, we will get a state that source and
snapshot root share same space, but source root have written data into
fallocated space, this will make fsck fail to verify checksums for
snapshot root's preallocating file extent data.Nocow writting also
has this same problem.

Fix this problem by syncing snapshots with nocow writting:

 1.for nocow writting,if there are pending snapshots, we will
 fall into COW way.

 2.if there are pending nocow writes, snapshots for this root
 will be blocked until nocow writting finish.

Reported-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:43 -07:00
Linus Torvalds 53c566625f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs changes from Chris Mason:
 "This is a pretty long stream of bug fixes and performance fixes.

  Qu Wenruo has replaced the btrfs async threads with regular kernel
  workqueues.  We'll keep an eye out for performance differences, but
  it's nice to be using more generic code for this.

  We still have some corruption fixes and other patches coming in for
  the merge window, but this batch is tested and ready to go"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (108 commits)
  Btrfs: fix a crash of clone with inline extents's split
  btrfs: fix uninit variable warning
  Btrfs: take into account total references when doing backref lookup
  Btrfs: part 2, fix incremental send's decision to delay a dir move/rename
  Btrfs: fix incremental send's decision to delay a dir move/rename
  Btrfs: remove unnecessary inode generation lookup in send
  Btrfs: fix race when updating existing ref head
  btrfs: Add trace for btrfs_workqueue alloc/destroy
  Btrfs: less fs tree lock contention when using autodefrag
  Btrfs: return EPERM when deleting a default subvolume
  Btrfs: add missing kfree in btrfs_destroy_workqueue
  Btrfs: cache extent states in defrag code path
  Btrfs: fix deadlock with nested trans handles
  Btrfs: fix possible empty list access when flushing the delalloc inodes
  Btrfs: split the global ordered extents mutex
  Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
  Btrfs: reclaim delalloc metadata more aggressively
  Btrfs: remove unnecessary lock in may_commit_transaction()
  Btrfs: remove the unnecessary flush when preparing the pages
  Btrfs: just do dirty page flush for the inode with compression before direct IO
  ...
2014-04-04 15:31:36 -07:00
Johannes Weiner 91b0abe36a mm + fs: store shadow entries in page cache
Reclaim will be leaving shadow entries in the page cache radix tree upon
evicting the real page.  As those pages are found from the LRU, an
iput() can lead to the inode being freed concurrently.  At this point,
reclaim must no longer install shadow pages because the inode freeing
code needs to ensure the page tree is really empty.

Add an address_space flag, AS_EXITING, that the inode freeing code sets
under the tree lock before doing the final truncate.  Reclaim will check
for this flag before installing shadow pages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Metin Doslu <metin@citusdata.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Ozgun Erdogan <ozgun@citusdata.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:01 -07:00
Miao Xie 573bfb72f7 Btrfs: fix possible empty list access when flushing the delalloc inodes
We didn't have a lock to protect the access to the delalloc inodes list, that is
we might access a empty delalloc inodes list if someone start flushing delalloc
inodes because the delalloc inodes were moved into a other list temporarily.
Fix it by wrapping the access with a lock.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:29 -04:00
Miao Xie 6c255e67ce Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
We needn't flush all delalloc inodes when we doesn't get s_umount lock,
or we would make the tasks wait for a long time.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:27 -04:00
Miao Xie 41bd9ca459 Btrfs: just do dirty page flush for the inode with compression before direct IO
As the comment in the btrfs_direct_IO says, only the compressed pages need be
flush again to make sure they are on the disk, but the common pages needn't,
so we add a if statement to check if the inode has compressed pages or not,
if no, skip the flush.

And in order to prevent the write ranges from intersecting, we need wait for
the running ordered extents. But the current code waits for them twice, one
is done before the direct IO starts (in btrfs_wait_ordered_range()), the other
is before we get the blocks, it is unnecessary. because we can do the direct
IO without holding i_mutex, it means that the intersected ordered extents may
happen during the direct IO, the first wait can not avoid this problem. So we
use filemap_fdatawrite_range() instead of btrfs_wait_ordered_range() to remove
the first wait.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:24 -04:00
Qu Wenruo d458b0540e btrfs: Cleanup the "_struct" suffix in btrfs_workequeue
Since the "_struct" suffix is mainly used for distinguish the differnt
btrfs_work between the original and the newly created one,
there is no need using the suffix since all btrfs_workers are changed
into btrfs_workqueue.

Also this patch fixed some codes whose code style is changed due to the
too long "_struct" suffix.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:16 -04:00
Qu Wenruo dc6e320998 btrfs: Replace fs_info->fixup_workers workqueue with btrfs_workqueue.
Replace the fs_info->fixup_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:12 -04:00
Qu Wenruo fccb5d86d8 btrfs: Replace fs_info->endio_* workqueue with btrfs_workqueue.
Replace the fs_info->endio_* workqueues with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:08 -04:00
Qu Wenruo a44903abe9 btrfs: Replace fs_info->flush_workers with btrfs_workqueue.
Replace the fs_info->submit_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:07 -04:00
Qu Wenruo afe3d24267 btrfs: Replace fs_info->delalloc_workers with btrfs_workqueue
Much like the fs_info->workers, replace the fs_info->delalloc_workers
use the same btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:06 -04:00
Miao Xie 7b2b70851f Btrfs: fix preallocate vs double nocow write
We can not release the reserved metadata space for the first write if we
find the write position is pre-allocated. Because the kernel might write
the data on the disk before we do the second write but after the can-nocow
check, if we release the space for the first write, we might fail to update
the metadata because of no space.

Fix this problem by end nocow write if there is dirty data in the range whose
space is pre-allocated.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:00 -04:00
Liu Bo 7813b3db0a Btrfs: avoid warning bomb of btrfs_invalidate_inodes
So after transaction is aborted, we need to cleanup inode resources by
calling btrfs_invalidate_inodes(), and btrfs_invalidate_inodes() hopes
roots' refs to be zero in old times and sets a WARN_ON(), however, this
is not always true within cleaning up transaction, so we get to detect
transaction abortion and not warn at all.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:38 -04:00
Wang Shilong bcbba5e659 Btrfs: skip readonly root for snapshot-aware defragment
Btrfs send is assuming readonly root won't change, let's skip readonly root.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:34 -04:00
Josef Bacik 29bce2f399 Btrfs: unlock extent and pages on error in cow_file_range
When I converted the BUG_ON() for the free_space_cache_inode in cow_file_range I
made it so we just return an error instead of unlocking all of our various
stuff.  This is a mistake and causes us to hang when we run into this.  This
patch fixes this problem.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:53 -04:00
Josef Bacik c581afc8db Btrfs: balance delayed inode updates
While trying to reproduce a delayed ref problem I noticed the box kept falling
over using all 80gb of my ram with btrfs_inode's and btrfs_delayed_node's.
Turns out this is because we only throttle delayed inode updates in
btrfs_dirty_inode, which doesn't actually get called that often, especially when
all you are doing is creating a bunch of files.  So balance delayed inode
updates everytime we create a new inode.  With this patch we no longer use up
all of our ram with delayed inode updates.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:52 -04:00
Linus Torvalds 3962dfbe22 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "We have a small collection of fixes in my for-linus branch.

  The big thing that stands out is a revert of a new ioctl.  Users
  haven't shipped yet in btrfs-progs, and Dave Sterba found a better way
  to export the information"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: use right clone root offset for compressed extents
  btrfs: fix null pointer deference at btrfs_sysfs_add_one+0x105
  Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol
  Btrfs: fix max_inline mount option
  Btrfs: fix a lockdep warning when cleaning up aborted transaction
  Revert "btrfs: add ioctl to export size of global metadata reservation"
2014-02-16 11:05:27 -08:00
Josef Bacik 3a0dfa6a12 Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol
A user was running into errors from an NFS export of a subvolume that had a
default subvol set.  When we mount a default subvol we will use d_obtain_alias()
to find an existing dentry for the subvolume in the case that the root subvol
has already been mounted, or a dummy one is allocated in the case that the root
subvol has not already been mounted.  This allows us to connect the dentry later
on if we wander into the path.  However if we don't ever wander into the path we
will keep DCACHE_DISCONNECTED set for a long time, which angers NFS.  It doesn't
appear to cause any problems but it is annoying nonetheless, so simply unset
DCACHE_DISCONNECTED in the get_default_root case and switch btrfs_lookup() to
use d_materialise_unique() instead which will make everything play nicely
together and reconnect stuff if we wander into the defaul subvol path from a
different way.  With this patch I'm no longer getting the NFS errors when
exporting a volume that has been mounted with a default subvol set.  Thanks,

cc: bfields@fieldses.org
cc: ebiederm@xmission.com
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-14 13:44:32 -08:00
Linus Torvalds 878a876b2e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Filipe is fixing compile and boot problems with our crc32c rework, and
  Josef has disabled snapshot aware defrag for now.

  As the number of snapshots increases, we're hitting OOM.  For the
  short term we're disabling things until a bigger fix is ready"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: use late_initcall instead of module_init
  Btrfs: use btrfs_crc32c everywhere instead of libcrc32c
  Btrfs: disable snapshot aware defrag for now
2014-02-04 12:26:56 -08:00
Josef Bacik 8101c8dbf6 Btrfs: disable snapshot aware defrag for now
It's just broken and it's taking a lot of effort to fix it, so for now just
disable it so people can defrag in peace.  Thanks,

Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-03 09:01:27 -08:00
Linus Torvalds e7651b819e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This is a pretty big pull, and most of these changes have been
  floating in btrfs-next for a long time.  Filipe's properties work is a
  cool building block for inheriting attributes like compression down on
  a per inode basis.

  Jeff Mahoney kicked in code to export filesystem info into sysfs.

  Otherwise, lots of performance improvements, cleanups and bug fixes.

  Looks like there are still a few other small pending incrementals, but
  I wanted to get the bulk of this in first"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (149 commits)
  Btrfs: fix spin_unlock in check_ref_cleanup
  Btrfs: setup inode location during btrfs_init_inode_locked
  Btrfs: don't use ram_bytes for uncompressed inline items
  Btrfs: fix btrfs_search_slot_for_read backwards iteration
  Btrfs: do not export ulist functions
  Btrfs: rework ulist with list+rb_tree
  Btrfs: fix memory leaks on walking backrefs failure
  Btrfs: fix send file hole detection leading to data corruption
  Btrfs: add a reschedule point in btrfs_find_all_roots()
  Btrfs: make send's file extent item search more efficient
  Btrfs: fix to catch all errors when resolving indirect ref
  Btrfs: fix protection between walking backrefs and root deletion
  btrfs: fix warning while merging two adjacent extents
  Btrfs: fix infinite path build loops in incremental send
  btrfs: undo sysfs when open_ctree() fails
  Btrfs: fix snprintf usage by send's gen_unique_name
  btrfs: fix defrag 32-bit integer overflow
  btrfs: sysfs: list the NO_HOLES feature
  btrfs: sysfs: don't show reserved incompat feature
  btrfs: call permission checks earlier in ioctls and return EPERM
  ...
2014-01-30 20:08:20 -08:00
Linus Torvalds f568849eda Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block
Pull core block IO changes from Jens Axboe:
 "The major piece in here is the immutable bio_ve series from Kent, the
  rest is fairly minor.  It was supposed to go in last round, but
  various issues pushed it to this release instead.  The pull request
  contains:

   - Various smaller blk-mq fixes from different folks.  Nothing major
     here, just minor fixes and cleanups.

   - Fix for a memory leak in the error path in the block ioctl code
     from Christian Engelmayer.

   - Header export fix from CaiZhiyong.

   - Finally the immutable biovec changes from Kent Overstreet.  This
     enables some nice future work on making arbitrarily sized bios
     possible, and splitting more efficient.  Related fixes to immutable
     bio_vecs:

        - dm-cache immutable fixup from Mike Snitzer.
        - btrfs immutable fixup from Muthu Kumar.

  - bio-integrity fix from Nic Bellinger, which is also going to stable"

* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
  xtensa: fixup simdisk driver to work with immutable bio_vecs
  block/blk-mq-cpu.c: use hotcpu_notifier()
  blk-mq: for_each_* macro correctness
  block: Fix memory leak in rw_copy_check_uvector() handling
  bio-integrity: Fix bio_integrity_verify segment start bug
  block: remove unrelated header files and export symbol
  blk-mq: uses page->list incorrectly
  blk-mq: use __smp_call_function_single directly
  btrfs: fix missing increment of bi_remaining
  Revert "block: Warn and free bio if bi_end_io is not set"
  block: Warn and free bio if bi_end_io is not set
  blk-mq: fix initializing request's start time
  block: blk-mq: don't export blk_mq_free_queue()
  block: blk-mq: make blk_sync_queue support mq
  block: blk-mq: support draining mq queue
  dm cache: increment bi_remaining when bi_end_io is restored
  block: fixup for generic bio chaining
  block: Really silence spurious compiler warnings
  block: Silence spurious compiler warnings
  block: Kill bio_pair_split()
  ...
2014-01-30 11:19:05 -08:00
Chris Mason 90d3e592e9 Btrfs: setup inode location during btrfs_init_inode_locked
We have a race during inode init because the BTRFS_I(inode)->location is setup
after the inode hash table lock is dropped.  btrfs_find_actor uses the location
field, so our search might not find an existing inode in the hash table if we
race with the inode init code.

This commit changes things to setup the location field sooner.  Also the find actor now
uses only the location objectid to match inodes.  For inode hashing, we just
need a unique and stable test, it doesn't have to reflect the inode numbers we
show to userland.

Signed-off-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org
2014-01-29 07:06:30 -08:00
Chris Mason 514ac8ad87 Btrfs: don't use ram_bytes for uncompressed inline items
If we truncate an uncompressed inline item, ram_bytes isn't updated to reflect
the new size.  The fixe uses the size directly from the item header when
reading uncompressed inlines, and also fixes truncate to update the
size as it goes.

Reported-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org
2014-01-29 07:06:29 -08:00
Gui Hecheng 3c9665df0c btrfs: fix warning while merging two adjacent extents
When we have two adjacent extents in relink_extent_backref,
we try to merge them. When we use btrfs_search_slot to locate the
slot for the current extent, we shouldn't set "ins_len = 1",
because we will merge it into the previous extent rather than
insert a new item. Otherwise, we may happen to create a new leaf
in btrfs_search_slot and path->slot[0] will be 0. Then we try to
fetch the previous item using "path->slots[0]--", and it will cause
a warning as follows:

	[  145.713385] WARNING: CPU: 3 PID: 1796 at fs/btrfs/extent_io.c:5043 map_private_extent_buffer+0xd4/0xe0
	[  145.713387] btrfs bad mapping eb start 5337088 len 4096, wanted 167772306 8
	...
	[  145.713462]  [<ffffffffa034b1f4>] map_private_extent_buffer+0xd4/0xe0
	[  145.713476]  [<ffffffffa030097a>] ? btrfs_free_path+0x2a/0x40
	[  145.713485]  [<ffffffffa0340864>] btrfs_get_token_64+0x64/0xf0
	[  145.713498]  [<ffffffffa033472c>] relink_extent_backref+0x41c/0x820
	[  145.713508]  [<ffffffffa0334d69>] btrfs_finish_ordered_io+0x239/0xa80

I encounter this warning when running defrag having mkfs.btrfs
with option -M. At the same time there are read/writes & snapshots
running at background.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:22 -08:00
Wang Shilong 2c21b4d733 Btrfs: fix transaction abortion when remounting btrfs from RW to RO
Steps to reproduce:
 # mkfs.btrfs -f /dev/sda8
 # mount /dev/sda8 /mnt -o flushoncommit
 # dd if=/dev/zero of=/mnt/data bs=4k count=102400 &
 # mount /dev/sda8 /mnt -o remount, ro

When remounting RW to RO, the logic is to firstly set flag
to RO and then commit transaction, however with option
flushoncommit enabled,we will do RO check within committing
transaction, so we get a transaction abortion here.

Actually,here check is wrong, we should check if FS_STATE_ERROR
is set, fix it.

Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Suggested-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:36 -08:00
Filipe David Borba Manana 63541927c8 Btrfs: add support for inode properties
This change adds infrastructure to allow for generic properties for
inodes. Properties are name/value pairs that can be associated with
inodes for different purposes. They are stored as xattrs with the
prefix "btrfs."

Properties can be inherited - this means when a directory inode has
inheritable properties set, these are added to new inodes created
under that directory. Further, subvolumes can also have properties
associated with them, and they can be inherited from their parent
subvolume. Naturally, directory properties have priority over subvolume
properties (in practice a subvolume property is just a regular
property associated with the root inode, objectid 256, of the
subvolume's fs tree).

This change also adds one specific property implementation, named
"compression", whose values can be "lzo" or "zlib" and it's an
inheritable property.

The corresponding changes to btrfs-progs were also implemented.
A patch with xfstests for this feature will follow once there's
agreement on this change/feature.

Further, the script at the bottom of this commit message was used to
do some benchmarks to measure any performance penalties of this feature.

Basically the tests correspond to:

Test 1 - create a filesystem and mount it with compress-force=lzo,
then sequentially create N files of 64Kb each, measure how long it took
to create the files, unmount the filesystem, mount the filesystem and
perform an 'ls -lha' against the test directory holding the N files, and
report the time the command took.

Test 2 - create a filesystem and don't use any compression option when
mounting it - instead set the compression property of the subvolume's
root to 'lzo'. Then create N files of 64Kb, and report the time it took.
The unmount the filesystem, mount it again and perform an 'ls -lha' like
in the former test. This means every single file ends up with a property
(xattr) associated to it.

Test 3 - same as test 2, but uses 4 properties - 3 are duplicates of the
compression property, have no real effect other than adding more work
when inheriting properties and taking more btree leaf space.

Test 4 - same as test 3 but with 10 properties per file.

Results (in seconds, and averages of 5 runs each), for different N
numbers of files follow.

* Without properties (test 1)

                    file creation time        ls -lha time
10 000 files              3.49                   0.76
100 000 files            47.19                   8.37
1 000 000 files         518.51                 107.06

* With 1 property (compression property set to lzo - test 2)

                    file creation time        ls -lha time
10 000 files              3.63                    0.93
100 000 files            48.56                    9.74
1 000 000 files         537.72                  125.11

* With 4 properties (test 3)

                    file creation time        ls -lha time
10 000 files              3.94                    1.20
100 000 files            52.14                   11.48
1 000 000 files         572.70                  142.13

* With 10 properties (test 4)

                    file creation time        ls -lha time
10 000 files              4.61                    1.35
100 000 files            58.86                   13.83
1 000 000 files         656.01                  177.61

The increased latencies with properties are essencialy because of:

*) When creating an inode, we now synchronously write 1 more item
   (an xattr item) for each property inherited from the parent dir
   (or subvolume). This could be done in an asynchronous way such
   as we do for dir intex items (delayed-inode.c), which could help
   reduce the file creation latency;

*) With properties, we now have larger fs trees. For this particular
   test each xattr item uses 75 bytes of leaf space in the fs tree.
   This could be less by using a new item for xattr items, instead of
   the current btrfs_dir_item, since we could cut the 'location' and
   'type' fields (saving 18 bytes) and maybe 'transid' too (saving a
   total of 26 bytes per xattr item) from the btrfs_dir_item type.

Also tried batching the xattr insertions (ignoring proper hash
collision handling, since it didn't exist) when creating files that
inherit properties from their parent inode/subvolume, but the end
results were (surprisingly) essentially the same.

Test script:

$ cat test.pl
  #!/usr/bin/perl -w

  use strict;
  use Time::HiRes qw(time);
  use constant NUM_FILES => 10_000;
  use constant FILE_SIZES => (64 * 1024);
  use constant DEV => '/dev/sdb4';
  use constant MNT_POINT => '/home/fdmanana/btrfs-tests/dev';
  use constant TEST_DIR => (MNT_POINT . '/testdir');

  system("mkfs.btrfs", "-l", "16384", "-f", DEV) == 0 or die "mkfs.btrfs failed!";

  # following line for testing without properties
  #system("mount", "-o", "compress-force=lzo", DEV, MNT_POINT) == 0 or die "mount failed!";

  # following 2 lines for testing with properties
  system("mount", DEV, MNT_POINT) == 0 or die "mount failed!";
  system("btrfs", "prop", "set", MNT_POINT, "compression", "lzo") == 0 or die "set prop failed!";

  system("mkdir", TEST_DIR) == 0 or die "mkdir failed!";
  my ($t1, $t2);

  $t1 = time();
  for (my $i = 1; $i <= NUM_FILES; $i++) {
      my $p = TEST_DIR . '/file_' . $i;
      open(my $f, '>', $p) or die "Error opening file!";
      $f->autoflush(1);
      for (my $j = 0; $j < FILE_SIZES; $j += 4096) {
          print $f ('A' x 4096) or die "Error writing to file!";
      }
      close($f);
  }
  $t2 = time();
  print "Time to create " . NUM_FILES . ": " . ($t2 - $t1) . " seconds.\n";
  system("umount", DEV) == 0 or die "umount failed!";
  system("mount", DEV, MNT_POINT) == 0 or die "mount failed!";

  $t1 = time();
  system("bash -c 'ls -lha " . TEST_DIR . " > /dev/null'") == 0 or die "ls failed!";
  $t2 = time();
  print "Time to ls -lha all files: " . ($t2 - $t1) . " seconds.\n";
  system("umount", DEV) == 0 or die "umount failed!";

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:24 -08:00
Filipe David Borba Manana 1acae57b16 Btrfs: faster file extent item replace operations
When writing to a file we drop existing file extent items that cover the
write range and then add a new file extent item that represents that write
range.

Before this change we were doing a tree lookup to remove the file extent
items, and then after we did another tree lookup to insert the new file
extent item.
Most of the time all the file extent items we need to drop are located
within a single leaf - this is the leaf where our new file extent item ends
up at. Therefore, in this common case just combine these 2 operations into
a single one.

By avoiding the second btree navigation for insertion of the new file extent
item, we reduce btree node/leaf lock acquisitions/releases, btree block/leaf
COW operations, CPU time on btree node/leaf key binary searches, etc.

Besides for file writes, this is an operation that happens for file fsync's
as well. However log btrees are much less likely to big as big as regular
fs btrees, therefore the impact of this change is smaller.

The following benchmark was performed against an SSD drive and a
HDD drive, both for random and sequential writes:

  sysbench --test=fileio --file-num=4096 --file-total-size=8G \
     --file-test-mode=[rndwr|seqwr] --num-threads=512 \
     --file-block-size=8192 \ --max-requests=1000000 \
     --file-fsync-freq=0 --file-io-mode=sync [prepare|run]

All results below are averages of 10 runs of the respective test.

** SSD sequential writes

Before this change: 225.88 Mb/sec
After this change:  277.26 Mb/sec

** SSD random writes

Before this change: 49.91 Mb/sec
After this change:  56.39 Mb/sec

** HDD sequential writes

Before this change: 68.53 Mb/sec
After this change:  69.87 Mb/sec

** HDD random writes

Before this change: 13.04 Mb/sec
After this change:  14.39 Mb/sec

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:23 -08:00
Miao Xie e77751aad1 Btrfs: fix the wrong nocow range check
The following warning message was outputed when running the 274th case
of xfstests with nodatacow option:
 BUG: Bad page state in process kswapd0  pfn:1c66f
 page:ffffea0000636848 count:0 mapcount:0 mapping:(null) index:0x78000
 page flags: 0x1000000000100a(error|uptodate|private_2)

It is because the check of nocow range was wrong, we should compare the
start and end position of the extent with the write position to verify
if the write position was in the extent, but the current code just used
the start postion to do the check, so we got the wrong extent and told
the caller that it was a nocow write. And then when we write back the
dirty pages, we found we should cow the extent, but at that time, there
was no space in the fs, we had to the error flag for the page. When
someone reclaimed that page, the above warning outputed. Fix it.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:13 -08:00
Filipe David Borba Manana eb653de159 Btrfs: reduce btree node locking duration on item update
If we do a btree search with the goal of updating an existing item
without changing its size (ins_len == 0 and cow == 1), then we never
need to hold locks on upper level nodes (even when slot == 0) after we
COW their child nodes/leaves, as we won't have node splits or merges
in this scenario (that is, no key additions, removals or shifts on any
nodes or leaves).

Therefore release the locks immediately after COWing the child nodes/leaves
while navigating the btree, even if their parent slot is 0, instead of
returning a path to the caller with those nodes locked, which would get
released only when the caller releases or frees the path (or if it calls
btrfs_unlock_up_safe).

This is a common scenario, for example when updating inode items in fs
trees and block group items in the extent tree.

The following benchmarks were performed on a quad core machine with 32Gb
of ram, using a leaf/node size of 4Kb (to generate deeper fs trees more
quickly).

  sysbench --test=fileio --file-num=131072 --file-total-size=8G \
    --file-test-mode=seqwr --num-threads=512 --file-block-size=8192 \
    --max-requests=100000 --file-io-mode=sync [prepare|run]

Before this change:  49.85Mb/s (average of 5 runs)
After this change:   50.38Mb/s (average of 5 runs)

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:11 -08:00
Miao Xie 67de11769b Btrfs: introduce the delayed inode ref deletion for the single link inode
The inode reference item is close to inode item, so we insert it simultaneously
with the inode item insertion when we create a file/directory.. In fact, we also
can handle the inode reference deletion by the same way. So we made this patch to
introduce the delayed inode reference deletion for the single link inode(At most
case, the file doesn't has hard link, so we don't take the hard link into account).

This function is based on the delayed inode mechanism. After applying this patch,
we can reduce the time of the file/directory deletion by ~10%.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:09 -08:00
Frank Holton efe120a067 Btrfs: convert printk to btrfs_ and fix BTRFS prefix
Convert all applicable cases of printk and pr_* to the btrfs_* macros.

Fix all uses of the BTRFS prefix.

Signed-off-by: Frank Holton <fholton@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:05 -08:00
Wang Shilong 180589efde Btrfs: fix a warning when iput a file
See the warning below:

[ 1209.102076]  [<ffffffffa04721b9>] remove_extent_mapping+0x69/0x70 [btrfs]
[ 1209.102084]  [<ffffffffa0466b06>] btrfs_evict_inode+0x96/0x4d0 [btrfs]
[ 1209.102089]  [<ffffffff81073010>] ? wake_atomic_t_function+0x40/0x40
[ 1209.102092]  [<ffffffff8118ab2e>] evict+0x9e/0x190
[ 1209.102094]  [<ffffffff8118b313>] iput+0xf3/0x180
[ 1209.102101]  [<ffffffffa0461fd1>] btrfs_run_delayed_iputs+0xb1/0xd0 [btrfs]
[ 1209.102107]  [<ffffffffa045d358>] __btrfs_end_transaction+0x268/0x350 [btrfs]

clear extent bit here to avoid triggering WARN_ON() in remove_extent_mapping()

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:02 -08:00
Wang Shilong 663df05330 Btrfs: remove dead comments for read_csums()
Chris introduced hleper function  read_csums() and this function
has been removed, but we forgot to remove its corresponding comments.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:59 -08:00
Tsutomu Itoh 5662344b3c Btrfs: fix error check of btrfs_lookup_dentry()
Clean up btrfs_lookup_dentry() to never return NULL, but PTR_ERR(-ENOENT)
instead. This keeps the return value convention consistent.

Callers who use btrfs_lookup_dentry() require a trivial update.

create_snapshot() in particular looks like it can also lose a BUG_ON(!inode)
which is not really needed - there seems less harm in returning ENOENT to
userspace at that point in the stack than there is to crash the machine.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:56 -08:00
Filipe David Borba Manana 131e404a2a Btrfs: fix very slow inode eviction and fs unmount
The inode eviction can be very slow, because during eviction we
tell the VFS to truncate all of the inode's pages. This results
in calls to btrfs_invalidatepage() which in turn does calls to
lock_extent_bits() and clear_extent_bit(). These calls result in
too many merges and splits of extent_state structures, which
consume a lot of time and cpu when the inode has many pages. In
some scenarios I have experienced umount times higher than 15
minutes, even when there's no pending IO (after a btrfs fs sync).

A quick way to reproduce this issue:

$ mkfs.btrfs -f /dev/sdb3
$ mount /dev/sdb3 /mnt/btrfs
$ cd /mnt/btrfs
$ sysbench --test=fileio --file-num=128 --file-total-size=16G \
    --file-test-mode=seqwr --num-threads=128 \
    --file-block-size=16384 --max-time=60 --max-requests=0 run
$ time btrfs fi sync .
FSSync '.'

real	0m25.457s
user	0m0.000s
sys	0m0.092s
$ cd ..
$ time umount /mnt/btrfs

real	1m38.234s
user	0m0.000s
sys	1m25.760s

The same test on ext4 runs much faster:

$ mkfs.ext4 /dev/sdb3
$ mount /dev/sdb3 /mnt/ext4
$ cd /mnt/ext4
$ sysbench --test=fileio --file-num=128 --file-total-size=16G \
    --file-test-mode=seqwr --num-threads=128 \
    --file-block-size=16384 --max-time=60 --max-requests=0 run
$ sync
$ cd ..
$ time umount /mnt/ext4

real	0m3.626s
user	0m0.004s
sys	0m3.012s

After this patch, the unmount (inode evictions) is much faster:

$ mkfs.btrfs -f /dev/sdb3
$ mount /dev/sdb3 /mnt/btrfs
$ cd /mnt/btrfs
$ sysbench --test=fileio --file-num=128 --file-total-size=16G \
    --file-test-mode=seqwr --num-threads=128 \
    --file-block-size=16384 --max-time=60 --max-requests=0 run
$ time btrfs fi sync .
FSSync '.'

real	0m26.774s
user	0m0.000s
sys	0m0.084s
$ cd ..
$ time umount /mnt/btrfs

real	0m1.811s
user	0m0.000s
sys	0m1.564s

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:44 -08:00
Kelley Nielsen 75ac2dd907 btrfs: expand btrfs_find_item() to include find_root_ref functionality
This patch is the second step in bootstrapping the btrfs_find_item
interface. The btrfs_find_root_ref() is similar to the former
__inode_info(); it accepts four of its parameters, and duplicates the
first half of its functionality.

Replace the one former call to btrfs_find_root_ref() with a call to
btrfs_find_item(), along with the defined key type that was used
internally by btrfs_find_root ref, and a null found key. In
btrfs_find_item(), add a test for the null key at the place where
the functionality of btrfs_find_root_ref() ends; btrfs_find_item()
then returns if the test passes. Finally, remove btrfs_find_root_ref().

Signed-off-by: Kelley Nielsen <kelleynnn@gmail.com>
Suggested-by: Zach Brown <zab@redhat.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:36 -08:00
Valentina Giusti 99e22f783b btrfs: remove unused variable from btrfs_new_inode
Variable owner in btrfs_new_inode is unused since commit
d82a6f1d7e
(Btrfs: kill BTRFS_I(inode)->block_group)

Signed-off-by: Valentina Giusti <valentina.giusti@microon.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:31 -08:00
Josef Bacik 16e7549f04 Btrfs: incompatible format change to remove hole extents
Btrfs has always had these filler extent data items for holes in inodes.  This
has made somethings very easy, like logging hole punches and sending hole
punches.  However for large holey files these extent data items are pure
overhead.  So add an incompatible feature to no longer add hole extents to
reduce the amount of metadata used by these sort of files.  This has a few
changes for logging and send obviously since they will need to detect holes and
log/send the holes if there are any.  I've tested this thoroughly with xfstests
and it doesn't cause any issues with and without the incompat format set.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:21 -08:00
Linus Torvalds bf3d846b78 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted stuff; the biggest pile here is Christoph's ACL series.  Plus
  assorted cleanups and fixes all over the place...

  There will be another pile later this week"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (43 commits)
  __dentry_path() fixes
  vfs: Remove second variable named error in __dentry_path
  vfs: Is mounted should be testing mnt_ns for NULL or error.
  Fix race when checking i_size on direct i/o read
  hfsplus: remove can_set_xattr
  nfsd: use get_acl and ->set_acl
  fs: remove generic_acl
  nfs: use generic posix ACL infrastructure for v3 Posix ACLs
  gfs2: use generic posix ACL infrastructure
  jfs: use generic posix ACL infrastructure
  xfs: use generic posix ACL infrastructure
  reiserfs: use generic posix ACL infrastructure
  ocfs2: use generic posix ACL infrastructure
  jffs2: use generic posix ACL infrastructure
  hfsplus: use generic posix ACL infrastructure
  f2fs: use generic posix ACL infrastructure
  ext2/3/4: use generic posix ACL infrastructure
  btrfs: use generic posix ACL infrastructure
  fs: make posix_acl_create more useful
  fs: make posix_acl_chmod more useful
  ...
2014-01-28 08:38:04 -08:00
Christoph Hellwig 996a710d46 btrfs: use generic posix ACL infrastructure
Also don't bother to set up a .get_acl method for symlinks as we do not
support access control (ACLs or even mode bits) for symlinks in Linux.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-01-25 23:58:18 -05:00
Christoph Hellwig dff6efc326 fs: fix iversion handling
Currently notify_change directly updates i_version for size updates,
which not only is counter to how all other fields are updated through
struct iattr, but also breaks XFS, which need inode updates to happen
under its own lock, and synchronized to the structure that gets written
to the log.

Remove the update in the common code, and it to btrfs and ext4,
XFS already does a proper updaste internally and currently gets a
double update with the existing code.

IMHO this is 3.13 and -stable material and should go in through the XFS
tree.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Acked-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-12-05 16:36:21 -06:00
Kent Overstreet 4f024f3797 block: Abstract out bvec iterator
Immutable biovecs are going to require an explicit iterator. To
implement immutable bvecs, a later patch is going to add a bi_bvec_done
member to this struct; for now, this patch effectively just renames
things.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: xfs@oss.sgi.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchand@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peng Tao <tao.peng@emc.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Pankaj Kumar <pankaj.km@samsung.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>6
2013-11-23 22:33:47 -08:00
Kent Overstreet 2c30c71bd6 block: Convert various code to bio_for_each_segment()
With immutable biovecs we don't want code accessing bi_io_vec directly -
the uses this patch changes weren't incorrect since they all own the
bio, but it makes the code harder to audit for no good reason - also,
this will help with multipage bvecs later.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-11-23 22:33:46 -08:00
Steven Rostedt 4cd8587ce8 btrfs: Use trace condition for get_extent tracepoint
Doing an if statement to test some condition to know if we should
trigger a tracepoint is pointless when tracing is disabled. This just
adds overhead and wastes a branch prediction. This is why the
TRACE_EVENT_CONDITION() was created. It places the check inside the jump
label so that the branch does not happen unless tracing is enabled.

That is, instead of doing:

	if (em)
		trace_btrfs_get_extent(root, em);

Which is basically this:

	if (em)
		if (static_key(trace_btrfs_get_extent)) {

Using a TRACE_EVENT_CONDITION() we can just do:

	trace_btrfs_get_extent(root, em);

And the condition trace event will do:

	if (static_key(trace_btrfs_get_extent)) {
		if (em) {
			...

The static key is a non conditional jump (or nop) that is faster than
having to check if em is NULL or not.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:44:47 -05:00
Josef Bacik 4724b106b9 Btrfs: don't BUG_ON() if we get an error walking backrefs
We can just return false for this so we stop doing the snapshot aware defrag
stuff.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-20 20:41:16 -05:00
Miao Xie 91aef86f3b Btrfs: rename btrfs_start_all_delalloc_inodes
rename the function -- btrfs_start_all_delalloc_inodes(), and make its
name be compatible to btrfs_wait_ordered_roots(), since they are always
used at the same place.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:13:58 -05:00
Dulshani Gunawardhana 678712545b btrfs: Fix checkpatch.pl warning of spacing issues
Fix spacing issues detected via checkpatch.pl in accordance with the
kernel style guidelines.

Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:12:31 -05:00
Dulshani Gunawardhana fae7f21cec btrfs: Use WARN_ON()'s return value in place of WARN_ON(1)
Use WARN_ON()'s return value in place of WARN_ON(1) for cleaner source
code that outputs a more descriptive warnings. Also fix the styling
warning of redundant braces that came up as a result of this fix.

Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:11:53 -05:00
Liu Bo 6f519564d7 Btrfs: do not run snapshot-aware defragment on error
If something wrong happens in write endio, running snapshot-aware defragment
can end up with undefined results, maybe a crash, so we should avoid it.

In order to share similar code, this also adds a helper to free the struct for
snapshot-aware defrag.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:11:00 -05:00
Josef Bacik 9f23e289ed Btrfs: make sure the delalloc workers actually flush compressed writes
When using delalloc workers in a non-waiting way (like for enospc handling) we
can end up not actually waiting for the dirty pages to be started if we have
compression.  We need to add an extra filemap flush to make sure any async
extents that have started are actually moved along before returning.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:08:22 -05:00
Josef Bacik d788a34929 Btrfs: don't abort transaction in run_delalloc_nocow
This is just the write path, the only reason we start a transaction is so we can
check cross references, we don't make any actual changes, so there is no reason
to abort the transaction if we fail.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:07:58 -05:00
Josef Bacik 02ecd2c278 Btrfs: do not bug_on if we try to cow a free space cache inode
We can just return an error and we'll bail out properly.  We still want to catch
this case to make sure we don't have a bug somewhere, so just warn if this pops
up.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:07:49 -05:00
Josef Bacik 0ef8b72607 Btrfs: return an error from btrfs_wait_ordered_range
I noticed that if the free space cache has an error writing out it's data it
won't actually error out, it will just carry on.  This is because it doesn't
check the return value of btrfs_wait_ordered_range, which didn't actually return
anything.  So fix this in order to keep us from making free space cache look
valid when it really isnt.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:07:35 -05:00
Zach Brown 8b558c5f09 btrfs: remove fs/btrfs/compat.h
fs/btrfs/compat.h only contained trivial macro wrappers of drop_nlink()
and inc_nlink().  This doesn't belong in mainline.

Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:03:19 -05:00
Josef Bacik 25a50341b6 Btrfs: handle a missing extent for the first file extent
While trying to kill our hole extents I noticed I was seeing problems where we
seek into a file and then start writing and then try to fiemap that file later.
This is because we search for offset 0, don't find anything and so back up one
slot, which puts us at the inode ref or something like that, which means we goto
not_found and create an extent map for our entire search area.  This isn't quite
what we want, we want to move forward one slot and see if there is an extent
there so we can limit our hole extent.  This patch fixes this problem, I will
add a testcase for this as well.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:58:05 -05:00
Josef Bacik aaedb55bc0 Btrfs: add tests for btrfs_get_extent
I'm going to be removing hole extents in the near future so I wanted to make a
sanity test for btrfs_get_extent to make sure I don't break anything in the
meantime.  This patch just puts btrfs_get_extent through its paces by giving it
a completely unreasonable mapping to look at and make sure it is giving us back
maps that make sense.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:57:30 -05:00
Josef Bacik 857cc2fc29 Btrfs: free reserved space on error in a few places
While trying to track down a reserved space leak I noticed a few places where we
won't properly clean up reserved space if we have an error, this patch fixes
those up.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:56:41 -05:00
Filipe David Borba Manana 778ba82b17 Btrfs: improve inode hash function/inode lookup
Currently the hash value used for adding an inode to the VFS's inode
hash table consists of the plain inode number, which is a 64 bits
integer. This results in hash table buckets (hlist_head lists) with
too many elements for at least 2 important scenarios:

1) When we have many subvolumes. Each subvolume has its own btree
   where its files and directories are added to, and each has its
   own objectid (inode number) namespace. This means that if we have
   N subvolumes, and all have inode number X associated to a file or
   directory, the corresponding inodes all map to the same hash table
   entry, resulting in a bucket (hlist_head list) with N elements;

2) On 32 bits machines. Th VFS hash values are unsigned longs, which
   are 32 bits wide on 32 bits machines, and the inode (objectid)
   numbers are 64 bits unsigned integers. We simply cast the inode
   numbers to hash values, which means that for all inodes with the
   same 32 bits lower half, the same hash bucket is used for all of
   them. For example, all inodes with a number (objectid) between
   0x0000_0000_ffff_ffff and 0xffff_ffff_ffff_ffff will end up in
   the same hash table bucket.

This change ensures the inode's hash value depends both on the
objectid (inode number) and its subvolume's (btree root) objectid.
For 32 bits machines, this change gives better entropy by making
the hash value depend on both the upper and lower 32 bits of the
64 bits hash previously computed.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:55:19 -05:00
Miao Xie fa7c14947a Btrfs: improve jitter performance of the sequential buffered write
The performance was slowed down sometimes when we ran sysbench to measure
the performance of the sequential buffered write by 2 or more threads.

It was because the write order of the test threads might be confused
by the task scheduler, and the coming write would be beyond the end of
the file, in this case, we need insert dummy file extents and create
a hole for the area we skip. But in order to avoid the ongoing ordered
extents which are in the area, we need wait for them. Unfortunately,
the current code doesn't check if there are ordered extents in the area
or not, try to find and flush the dirty pages directly, but in fact,
there is no dirty page in that area, this step of the current code is
unnecessary, and just wastes time. Sometimes, it would increase
the contention of some locks, and makes the performance slow down suddenly.

So we remove the ordered extent flush function before the check, and flush
the dirty pages and wait for the ordered extents only when we find them.

According to my test, we got 1-2 times of the performance regression when
we ran the test by 10 times before applying this patch. After applying
this patch, the regression went away.

Test Environment:
 CPU:		1CPU * 4Cores
 Memory:	6GB
 Partition:	20GB

Test Command:
 # sysbench --test=fileio --file-total-size=16G --file-test-mode=seqwr \
 > --num-threads=512 --file-block-size=16384 --max-time=60 --max-requests=0 run

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:54:38 -05:00
Josef Bacik b6d08f0630 Btrfs: do not release metadata for space cache inodes
I've been testing our error paths and I was tripping the BUG_ON() in
drop_outstanding_extent because our outstanding_extents is 0 for space cache
inodes.  This is because we don't reserve metadata space for these inodes since
we depend on the global block reserve for our space.  To fix this we need to
make sure the DO_ACCOUNTING stuff doesn't actually call release_metadata for
space cache inodes.  With this patch I'm no longer panicing.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:53:36 -05:00
Filipe David Borba Manana 703c88e035 Btrfs: fix tracking of orphan inode count
In inode.c:btrfs_orphan_add() if we failed to insert the orphan
item, we would return without decrementing the orphan count that
we just incremented before attempting the insertion, leaving the
orphan inode count wrong.

In inode.c:btrfs_orphan_del(), we were decrementing the inode
orphan count if the bit BTRFS_INODE_ORPHAN_META_RESERVED was set,
which is logically wrong because it should be decremented if the
bit BTRFS_INODE_HAS_ORPHAN_ITEM was set - after all we increment
the count when we set the bit BTRFS_INODE_HAS_ORPHAN_ITEM elsewhere.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:53:01 -05:00
Ross Kirk dd3cc16b87 btrfs: drop unused parameter from btrfs_item_nr
Remove unused eb parameter from btrfs_item_nr

Signed-off-by: Ross Kirk <ross.kirk@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:50:48 -05:00
Filipe David Borba Manana f06becc411 Btrfs: don't store NULL byte in symlink extents
It is not necessary to store the NULL byte in a symlink inline file
extent. There's currently no code that requires the NULL byte to be
present in the extent. This change also doesn't break file format
compatibility nor the send/receive feature.

The VFS also doesn't need the NULL byte to be present in the extent,
as it reads up to inode->i_size bytes (which already excluded the NULL
byte) and sets the NULL byte for us (in fs/namei.c:page_getlink()).

So with this change we save 1 byte per symlink file extent (which is
always inlined in the btree leaf) without losing backward and forward
compatibility.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:49:51 -05:00
Stefan Behrens 69e9c6c6dc Btrfs: eliminate the exceptional root_tree refs=0
The fact that btrfs_root_refs() returned 0 for the tree_root caused
bugs in the past, therefore it is set to 1 with this patch and
(hopefully) all affected code is adapted to this change.

I verified this change by temporarily adding WARN_ON() checks
everywhere where btrfs_root_refs() is used, checking whether the
logic of the code is changed by btrfs_root_refs() returning 1
instead of 0 for root->root_key.objectid == BTRFS_ROOT_TREE_OBJECTID.
With these added checks, I ran the xfstests './check -g auto'.

The two roots chunk_root and log_root_tree that are only referenced
by the superblock and the log_roots below the log_root_tree still
have btrfs_root_refs() == 0, only the tree_root is changed.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:49:26 -05:00
Linus Torvalds bdeeab62a6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fix from Chris Mason:
 "Sage hit a deadlock with ceph on btrfs, and Josef tracked it down to a
  regression in our initial rc1 pull.  When doing nocow writes we were
  sometimes starting a transaction with locks held"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: release path before starting transaction in can_nocow_extent
2013-10-18 16:46:21 -07:00
Josef Bacik 1bda19eb73 Btrfs: release path before starting transaction in can_nocow_extent
We can't be holding tree locks while we try to start a transaction, we will
deadlock.  Thanks,

Reported-by: Sage Weil <sage@inktank.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-10-18 12:43:40 -04:00
Linus Torvalds d64dab903f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "We've got more bug fixes in my for-linus branch:

  One of these fixes another corner of the compression oops from last
  time.  Miao nailed down some problems with concurrent snapshot
  deletion and drive balancing.

  I kept out one of his patches for more testing, but these are all
  stable"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix oops caused by the space balance and dead roots
  Btrfs: insert orphan roots into fs radix tree
  Btrfs: limit delalloc pages outside of find_delalloc_range
  Btrfs: use right root when checking for hash collision
2013-10-12 12:54:24 -07:00
Josef Bacik 4871c1588f Btrfs: use right root when checking for hash collision
btrfs_rename was using the root of the old dir instead of the root of the new
dir when checking for a hash collision, so if you tried to move a file into a
subvol it would freak out because it would see the file you are trying to move
in its current root.  This fixes the bug where this would fail

btrfs subvol create test1
btrfs subvol create test2
mv test1 test2.

Thanks to Chris Murphy for catching this,

Cc: stable@vger.kernel.org
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-10-10 21:27:45 -04:00
Linus Torvalds 0fbf2cc983 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "These are mostly bug fixes and a two small performance fixes.  The
  most important of the bunch are Josef's fix for a snapshotting
  regression and Mark's update to fix compile problems on arm"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (25 commits)
  Btrfs: create the uuid tree on remount rw
  btrfs: change extent-same to copy entire argument struct
  Btrfs: dir_inode_operations should use btrfs_update_time also
  btrfs: Add btrfs: prefix to kernel log output
  btrfs: refuse to remount read-write after abort
  Btrfs: btrfs_ioctl_default_subvol: Revert back to toplevel subvolume when arg is 0
  Btrfs: don't leak transaction in btrfs_sync_file()
  Btrfs: add the missing mutex unlock in write_all_supers()
  Btrfs: iput inode on allocation failure
  Btrfs: remove space_info->reservation_progress
  Btrfs: kill delay_iput arg to the wait_ordered functions
  Btrfs: fix worst case calculator for space usage
  Revert "Btrfs: rework the overcommit logic to be based on the total size"
  Btrfs: improve replacing nocow extents
  Btrfs: drop dir i_size when adding new names on replay
  Btrfs: replay dir_index items before other items
  Btrfs: check roots last log commit when checking if an inode has been logged
  Btrfs: actually log directory we are fsync()'ing
  Btrfs: actually limit the size of delalloc range
  Btrfs: allocate the free space by the existed max extent size when ENOSPC
  ...
2013-09-22 14:58:49 -07:00
Guangyu Sun 93fd63c2f0 Btrfs: dir_inode_operations should use btrfs_update_time also
Commit 2bc5565286 (Btrfs: don't update atime on
RO subvolumes) ensures that the access time of an inode is not updated when
the inode lives in a read-only subvolume.
However, if a directory on a read-only subvolume is accessed, the atime is
updated. This results in a write operation to a read-only subvolume. I
believe that access times should never be updated on read-only subvolumes.

To reproduce:

 # mkfs.btrfs -f /dev/dm-3
 (...)
 # mount /dev/dm-3 /mnt
 # btrfs subvol create /mnt/sub
 	Create subvolume '/mnt/sub'
 # mkdir /mnt/sub/dir
 # echo "abc" > /mnt/sub/dir/file
 # btrfs subvol snapshot -r /mnt/sub /mnt/rosnap
 	Create a readonly snapshot of '/mnt/sub' in '/mnt/rosnap'
 # stat /mnt/rosnap/dir
 	File: `/mnt/rosnap/dir'
 	Size: 8         Blocks: 0          IO Block: 4096   directory
 Device: 16h/22d    Inode: 257         Links: 1
 Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
 	Access: 2013-09-11 07:21:49.389157126 -0400
 	Modify: 2013-09-11 07:22:02.330156079 -0400
 	Change: 2013-09-11 07:22:02.330156079 -0400
 # ls /mnt/rosnap/dir
 	file
 # stat /mnt/rosnap/dir
 	File: `/mnt/rosnap/dir'
 	Size: 8         Blocks: 0          IO Block: 4096   directory
 Device: 16h/22d    Inode: 257         Links: 1
 Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
 	Access: 2013-09-11 07:22:56.797151670 -0400
 	Modify: 2013-09-11 07:22:02.330156079 -0400
 	Change: 2013-09-11 07:22:02.330156079 -0400

Reported-by: Koen De Wit <koen.de.wit@oracle.com>
Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-21 11:05:30 -04:00
Josef Bacik f4ab9ea706 Btrfs: iput inode on allocation failure
We don't do the iput when we fail to allocate our delayed delalloc work in
__start_delalloc_inodes, fix this.

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-21 11:05:28 -04:00
Filipe David Borba Manana cef2193729 Btrfs: more efficient inode tree replace operation
Instead of removing the current inode from the red black tree
and then add the new one, just use the red black tree replace
operation, which is more efficient.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-21 10:58:55 -04:00
Linus Torvalds ac4de9543a Merge branch 'akpm' (patches from Andrew Morton)
Merge more patches from Andrew Morton:
 "The rest of MM.  Plus one misc cleanup"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (35 commits)
  mm/Kconfig: add MMU dependency for MIGRATION.
  kernel: replace strict_strto*() with kstrto*()
  mm, thp: count thp_fault_fallback anytime thp fault fails
  thp: consolidate code between handle_mm_fault() and do_huge_pmd_anonymous_page()
  thp: do_huge_pmd_anonymous_page() cleanup
  thp: move maybe_pmd_mkwrite() out of mk_huge_pmd()
  mm: cleanup add_to_page_cache_locked()
  thp: account anon transparent huge pages into NR_ANON_PAGES
  truncate: drop 'oldsize' truncate_pagecache() parameter
  mm: make lru_add_drain_all() selective
  memcg: document cgroup dirty/writeback memory statistics
  memcg: add per cgroup writeback pages accounting
  memcg: check for proper lock held in mem_cgroup_update_page_stat
  memcg: remove MEMCG_NR_FILE_MAPPED
  memcg: reduce function dereference
  memcg: avoid overflow caused by PAGE_ALIGN
  memcg: rename RESOURCE_MAX to RES_COUNTER_MAX
  memcg: correct RESOURCE_MAX to ULLONG_MAX
  mm: memcg: do not trap chargers with full callstack on OOM
  mm: memcg: rework and document OOM waiting and wakeup
  ...
2013-09-12 15:44:27 -07:00
Kirill A. Shutemov 7caef26767 truncate: drop 'oldsize' truncate_pagecache() parameter
truncate_pagecache() doesn't care about old size since commit
cedabed49b ("vfs: Fix vmtruncate() regression").  Let's drop it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:02 -07:00
Linus Torvalds b7c09ad401 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This is against 3.11-rc7, but was pulled and tested against your tree
  as of yesterday.  We do have two small incrementals queued up, but I
  wanted to get this bunch out the door before I hop on an airplane.

  This is a fairly large batch of fixes, performance improvements, and
  cleanups from the usual Btrfs suspects.

  We've included Stefan Behren's work to index subvolume UUIDs, which is
  targeted at speeding up send/receive with many subvolumes or snapshots
  in place.  It closes a long standing performance issue that was built
  in to the disk format.

  Mark Fasheh's offline dedup work is also here.  In this case offline
  means the FS is mounted and active, but the dedup work is not done
  inline during file IO.  This is a building block where utilities are
  able to ask the FS to dedup a series of extents.  The kernel takes
  care of verifying the data involved really is the same.  Today this
  involves reading both extents, but we'll continue to evolve the
  patches"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits)
  Btrfs: optimize key searches in btrfs_search_slot
  Btrfs: don't use an async starter for most of our workers
  Btrfs: only update disk_i_size as we remove extents
  Btrfs: fix deadlock in uuid scan kthread
  Btrfs: stop refusing the relocation of chunk 0
  Btrfs: fix memory leak of uuid_root in free_fs_info
  btrfs: reuse kbasename helper
  btrfs: return btrfs error code for dev excl ops err
  Btrfs: allow partial ordered extent completion
  Btrfs: convert all bug_ons in free-space-cache.c
  Btrfs: add support for asserts
  Btrfs: adjust the fs_devices->missing count on unmount
  Btrf: cleanup: don't check for root_refs == 0 twice
  Btrfs: fix for patch "cleanup: don't check the same thing twice"
  Btrfs: get rid of one BUG() in write_all_supers()
  Btrfs: allocate prelim_ref with a slab allocater
  Btrfs: pass gfp_t to __add_prelim_ref() to avoid always using GFP_ATOMIC
  Btrfs: fix race conditions in BTRFS_IOC_FS_INFO ioctl
  Btrfs: fix race between removing a dev and writing sbs
  Btrfs: remove ourselves from the cluster list under lock
  ...
2013-09-12 09:58:51 -07:00