Commit Graph

51929 Commits

Author SHA1 Message Date
Nikolay Borisov
fd649f10c3 btrfs: Fix use-after-free when cleaning up fs_devs with a single stale device
Commit 4fde46f0cc ("Btrfs: free the stale device") introduced
btrfs_free_stale_device which iterates the device lists for all
registered btrfs filesystems and deletes those devices which aren't
mounted. In a btrfs_devices structure has only 1 device attached to it
and it is unused then btrfs_free_stale_devices will proceed to also free
the btrfs_fs_devices struct itself. Currently this leads to a use after
free since list_for_each_entry will try to perform a check on the
already freed memory to see if it has to terminate the loop.

The fix is to use 'break' when we know we are freeing the current
fs_devs.

Fixes: 4fde46f0cc ("Btrfs: free the stale device")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-05 17:15:14 +01:00
Filipe Manana
627e08738e Btrfs: fix null pointer dereference when replacing missing device
When we are replacing a missing device we mount the filesystem with the
degraded mode option in which case we are allowed to have a btrfs device
structure without a backing device member (its bdev member is NULL) and
therefore we can't dereference that member. Commit 38b5f68e98
("btrfs: drop btrfs_device::can_discard to query directly") started to
dereference that member when discarding extents, resulting in a null
pointer dereference:

 [ 3145.322257] BTRFS warning (device sdf): devid 2 uuid 4d922414-58eb-4880-8fed-9c3840f6c5d5 is missing
 [ 3145.364116] BTRFS info (device sdf): dev_replace from <missing disk> (devid 2) to /dev/sdg started
 [ 3145.413489] BUG: unable to handle kernel NULL pointer dereference at 00000000000000e0
 [ 3145.415085] IP: btrfs_discard_extent+0x6a/0xf8 [btrfs]
 [ 3145.415085] PGD 0 P4D 0
 [ 3145.415085] Oops: 0000 [#1] PREEMPT SMP PTI
 [ 3145.415085] Modules linked in: ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper evdev psmouse parport_pc serio_raw i2c_piix4 i2
 [ 3145.415085] CPU: 0 PID: 11989 Comm: btrfs Tainted: G        W        4.15.0-rc9-btrfs-next-55+ #1
 [ 3145.415085] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [ 3145.415085] RIP: 0010:btrfs_discard_extent+0x6a/0xf8 [btrfs]
 [ 3145.415085] RSP: 0018:ffffc90004813c60 EFLAGS: 00010293
 [ 3145.415085] RAX: ffff88020d39cc00 RBX: ffff88020c4ea2a0 RCX: 0000000000000002
 [ 3145.415085] RDX: 0000000000000000 RSI: ffff88020c4ea240 RDI: 0000000000000000
 [ 3145.415085] RBP: 0000000000000000 R08: 0000000000004000 R09: 0000000000000000
 [ 3145.415085] R10: ffffc90004813ae8 R11: 0000000000000000 R12: 0000000000000000
 [ 3145.415085] R13: ffff88020c418000 R14: 0000000000000000 R15: 0000000000000000
 [ 3145.415085] FS:  00007f565681f8c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [ 3145.415085] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [ 3145.415085] CR2: 00000000000000e0 CR3: 000000020d208006 CR4: 00000000001606f0
 [ 3145.415085] Call Trace:
 [ 3145.415085]  btrfs_finish_extent_commit+0x9a/0x1be [btrfs]
 [ 3145.415085]  btrfs_commit_transaction+0x649/0x7a0 [btrfs]
 [ 3145.415085]  ? start_transaction+0x2b0/0x3b3 [btrfs]
 [ 3145.415085]  btrfs_dev_replace_start+0x274/0x30c [btrfs]
 [ 3145.415085]  btrfs_dev_replace_by_ioctl+0x45/0x59 [btrfs]
 [ 3145.415085]  btrfs_ioctl+0x1a91/0x1d62 [btrfs]
 [ 3145.415085]  ? lock_acquire+0x16a/0x1af
 [ 3145.415085]  ? vfs_ioctl+0x1b/0x28
 [ 3145.415085]  ? trace_hardirqs_on_caller+0x14c/0x1a6
 [ 3145.415085]  vfs_ioctl+0x1b/0x28
 [ 3145.415085]  do_vfs_ioctl+0x5a9/0x5e0
 [ 3145.415085]  ? _raw_spin_unlock_irq+0x34/0x46
 [ 3145.415085]  ? entry_SYSCALL_64_fastpath+0x5/0x8b
 [ 3145.415085]  ? trace_hardirqs_on_caller+0x14c/0x1a6
 [ 3145.415085]  SyS_ioctl+0x52/0x76
 [ 3145.415085]  entry_SYSCALL_64_fastpath+0x1e/0x8b
 [ 3145.415085] RIP: 0033:0x7f56558b3c47
 [ 3145.415085] RSP: 002b:00007ffdcfac4c58 EFLAGS: 00000202
 [ 3145.415085] Code: be 02 00 00 00 4c 89 ef e8 b9 e7 03 00 85 c0 89 c5 75 75 48 8b 44 24 08 45 31 f6 48 8d 58 60 eb 52 48 8b 03 48 8b b8 a0 00 00 00 <48> 8b 87 e0 00
 [ 3145.415085] RIP: btrfs_discard_extent+0x6a/0xf8 [btrfs] RSP: ffffc90004813c60
 [ 3145.415085] CR2: 00000000000000e0
 [ 3145.458185] ---[ end trace 06302e7ac31902bf ]---

This is trivially reproduced by running the test btrfs/027 from fstests
like this:

  $ MOUNT_OPTIONS="-o discard" ./check btrfs/027

Fix this by skipping devices without a backing device before attempting
to discard.

Fixes: 38b5f68e98 ("btrfs: drop btrfs_device::can_discard to query directly")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:25:44 +01:00
Zygo Blaxell
c8195a7b1a btrfs: remove spurious WARN_ON(ref->count < 0) in find_parent_nodes
Until v4.14, this warning was very infrequent:

	WARNING: CPU: 3 PID: 18172 at fs/btrfs/backref.c:1391 find_parent_nodes+0xc41/0x14e0
	Modules linked in: [...]
	CPU: 3 PID: 18172 Comm: bees Tainted: G      D W    L  4.11.9-zb64+ #1
	Hardware name: System manufacturer System Product Name/M5A78L-M/USB3, BIOS 2101    12/02/2014
	Call Trace:
	 dump_stack+0x85/0xc2
	 __warn+0xd1/0xf0
	 warn_slowpath_null+0x1d/0x20
	 find_parent_nodes+0xc41/0x14e0
	 __btrfs_find_all_roots+0xad/0x120
	 ? extent_same_check_offsets+0x70/0x70
	 iterate_extent_inodes+0x168/0x300
	 iterate_inodes_from_logical+0x87/0xb0
	 ? iterate_inodes_from_logical+0x87/0xb0
	 ? extent_same_check_offsets+0x70/0x70
	 btrfs_ioctl+0x8ac/0x2820
	 ? lock_acquire+0xc2/0x200
	 do_vfs_ioctl+0x91/0x700
	 ? __fget+0x112/0x200
	 SyS_ioctl+0x79/0x90
	 entry_SYSCALL_64_fastpath+0x23/0xc6
	 ? trace_hardirqs_off_caller+0x1f/0x140

Starting with v4.14 (specifically 86d5f99442 ("btrfs: convert prelimary
reference tracking to use rbtrees")) the WARN_ON occurs three orders of
magnitude more frequently--almost once per second while running workloads
like bees.

Replace the WARN_ON() with a comment rationale for its removal.
The rationale is paraphrased from an explanation by Edmund Nadolski
<enadolski@suse.de> on the linux-btrfs mailing list.

Fixes: 8da6d5815c ("Btrfs: added btrfs_find_all_roots()")
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:25:33 +01:00
Nikolay Borisov
952bd3db0d btrfs: Ignore errors from btrfs_qgroup_trace_extent_post
Running generic/019 with qgroups on the scratch device enabled is almost
guaranteed to trigger the BUG_ON in btrfs_free_tree_block. It's supposed
to trigger only on -ENOMEM, in reality, however, it's possible to get
-EIO from btrfs_qgroup_trace_extent_post. This function just finds the
roots of the extent being tracked and sets the qrecord->old_roots list.
If this operation fails nothing critical happens except the quota
accounting can be considered wrong. In such case just set the
INCONSISTENT flag for the quota and print a warning, rather than killing
off the system. Additionally, it's possible to trigger a BUG_ON in
btrfs_truncate_inode_items as well.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
[ error message adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:25:14 +01:00
Liu Bo
900c998168 Btrfs: fix unexpected -EEXIST when creating new inode
The highest objectid, which is assigned to new inode, is decided at
the time of initializing fs roots.  However, in cases where log replay
gets processed, the btree which fs root owns might be changed, so we
have to search it again for the highest objectid, otherwise creating
new inode would end up with -EEXIST.

cc: <stable@vger.kernel.org> v4.4-rc6+
Fixes: f32e48e925 ("Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots")
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:24:53 +01:00
Liu Bo
1a932ef4e4 Btrfs: fix use-after-free on root->orphan_block_rsv
I got these from running generic/475,

WARNING: CPU: 0 PID: 26384 at fs/btrfs/inode.c:3326 btrfs_orphan_commit_root+0x1ac/0x2b0 [btrfs]
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: btrfs_block_rsv_release+0x1c/0x70 [btrfs]
Call Trace:
  btrfs_orphan_release_metadata+0x9f/0x200 [btrfs]
  btrfs_orphan_del+0x10d/0x170 [btrfs]
  btrfs_setattr+0x500/0x640 [btrfs]
  notify_change+0x7ae/0x870
  do_truncate+0xca/0x130
  vfs_truncate+0x2ee/0x3d0
  do_sys_truncate+0xaf/0xf0
  SyS_truncate+0xe/0x10
  entry_SYSCALL_64_fastpath+0x1f/0x96

The race is between btrfs_orphan_commit_root and btrfs_orphan_del,
        t1                                        t2
btrfs_orphan_commit_root                     btrfs_orphan_del
   spin_lock
   check (&root->orphan_inodes)
   root->orphan_block_rsv = NULL;
   spin_unlock
                                             atomic_dec(&root->orphan_inodes);
                                             access root->orphan_block_rsv

Accessing root->orphan_block_rsv must be done before decreasing
root->orphan_inodes.

cc: <stable@vger.kernel.org> v3.12+
Fixes: 703c88e035 ("Btrfs: fix tracking of orphan inode count")
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:24:40 +01:00
Liu Bo
e8f1bc1493 Btrfs: fix btrfs_evict_inode to handle abnormal inodes correctly
This regression is introduced in
commit 3d48d9810d ("btrfs: Handle uninitialised inode eviction").

There are two problems,

a) it is ->destroy_inode() that does the final free on inode, not
   ->evict_inode(),
b) clear_inode() must be called before ->evict_inode() returns.

This could end up hitting BUG_ON(inode->i_state != (I_FREEING | I_CLEAR));
in evict() because I_CLEAR is set in clear_inode().

Fixes: commit 3d48d9810d ("btrfs: Handle uninitialised inode eviction")
Cc: <stable@vger.kernel.org> # v4.7-rc6+
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:24:35 +01:00
Liu Bo
55237a5f24 Btrfs: fix extent state leak from tree log
It's possible that btrfs_sync_log() bails out after one of the two
btrfs_write_marked_extents() which convert extent state's state bit into
EXTENT_NEED_WAIT from EXTENT_DIRTY/EXTENT_NEW, however only EXTENT_DIRTY
and EXTENT_NEW are searched by free_log_tree() so that those extent states
with EXTENT_NEED_WAIT lead to memory leak.

cc: <stable@vger.kernel.org>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:24:30 +01:00
Liu Bo
1846430c24 Btrfs: fix crash due to not cleaning up tree log block's dirty bits
In cases that the whole fs flips into readonly status due to failures in
critical sections, then log tree's blocks are still dirty, and this leads
to a crash during umount time, the crash is about use-after-free,

umount
 -> close_ctree
    -> stop workers
    -> iput(btree_inode)
       -> iput_final
          -> write_inode_now
	     -> ...
	       -> queue job on stop'd workers

cc: <stable@vger.kernel.org> v3.12+
Fixes: 681ae50917 ("Btrfs: cleanup reserved space when freeing tree log on error")
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:24:24 +01:00
Liu Bo
e89166990f Btrfs: fix deadlock in run_delalloc_nocow
@cur_offset is not set back to what it should be (@cow_start) if
btrfs_next_leaf() returns something wrong, and the range [cow_start,
cur_offset) remains locked forever.

cc: <stable@vger.kernel.org>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-02 16:24:19 +01:00
Anand Jain
3acbcbfc8f btrfs: drop devid as device_list_add() arg
As struct btrfs_disk_super is being passed, so it can get devid
the same way its parent does.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-29 19:31:16 +01:00
Anand Jain
e124ece53e btrfs: get device pointer from device_list_add()
Instead of pointer to btrfs_fs_devices as an arg in device_list_add()
better to get pointer to btrfs_device as return value, then we have
both, pointer to btrfs_device and btrfs_fs_devices. btrfs_device is
needed to handle reappearing missing device.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-29 19:31:15 +01:00
Anand Jain
f2788d2f76 btrfs: set the total_devices in device_list_add()
There is no other parent for device_list_add() except for
btrfs_scan_one_device(), which would set btrfs_fs_devices::total_devices
if device_list_add is successful and this can be done with in
device_list_add() itself.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:56 +01:00
Anand Jain
327f18cc7f btrfs: move pr_info into device_list_add
Commit 60999ca4b4 ("btrfs: make device scan less noisy")
adds return value 1 to device_list_add(), so that parent function can
call pr_info only when new device is added. Move the pr_info() part
into device_list_add() so that this function can be kept simple.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:54 +01:00
Anand Jain
d8367db30a btrfs: make btrfs_free_stale_devices() to match the path
The btrfs_free_stale_devices() is updated to match for the given device
path and delete it. (It searches for only unmounted list of devices.)
Also drop the comment about different path being used for the same
device, since now we will have cli to clean any device that's not a
concern any more.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:52 +01:00
Anand Jain
0d34097f66 btrfs: rename btrfs_free_stale_devices() arg to skip_dev
No functional changes.
Rename btrfs_free_stale_devices() arg to skip_dev, so that it
reflects what that arg for.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:50 +01:00
Anand Jain
522f1b45e4 btrfs: make btrfs_free_stale_devices() argument optional
This updates btrfs_free_stale_devices() helper function to delete all
unmouted devices, when arg is NULL.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:48 +01:00
Anand Jain
38cf665d33 btrfs: make btrfs_free_stale_device() to iterate all stales
Let the list iterator iterate further and find other stale
devices and delete it. This is in preparation to add support
for user land request-able stale devices cleanup. Also rename
btrfs_free_stale_device() to btrfs_free_stale_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:47 +01:00
Anand Jain
a848b3e547 btrfs: no need to check for btrfs_fs_devices::seeding
There is no need to check for btrfs_fs_devices::seeding when we
have checked for btrfs_fs_devices::opened, because we can't sprout
without its seed FS being opened.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:44 +01:00
Nikolay Borisov
b03ebd992f btrfs: Use IS_ALIGNED in btrfs_truncate_block instead of opencoding it
No functional changes, just makes the code more readable

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
5f4791f4a6 Btrfs: noinline merge_extent_mapping
In order to debug subtle bugs around merge_extent_mapping(), perf probe
can be used to check the arguments, but sometimes merge_extent_mapping()
got inlined by compiler and couldn't be probed.

This is adding noinline attribute to merge_extent_mapping().

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
9a7e10e7ba Btrfs: add WARN_ONCE to detect unexpected error from merge_extent_mapping
This is a subtle case, so in order to understand the problem, it'd be good
to know the content of existing and em when any error occurs.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
cd77f4f836 Btrfs: extent map selftest: dio write vs dio read
This test case simulates the racy situation of dio write vs dio read,
and see if btrfs_get_extent() would return -EEXIST.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
fd87526fad Btrfs: extent map selftest: buffered write vs dio read
This test case simulates the racy situation of buffered write vs dio
read, and see if btrfs_get_extent() would return -EEXIST.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
72b28077a2 Btrfs: add extent map selftests
We've observed that btrfs_get_extent() and merge_extent_mapping() could
return -EEXIST in several cases, and they are caused by some racy
condition, e.g dio read vs dio write, which makes the problem very tricky
to reproduce.

This adds extent map selftests in order to simulate those racy situations.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
[ minor string adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
c04e61b5e4 Btrfs: move extent map specific code to extent_map.c
These helpers are extent map specific, move them to extent_map.c.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:22 +01:00
Liu Bo
7b4df058b0 Btrfs: add helper for em merge logic
This is a prepare work for the following extent map selftest, which
runs tests against em merge logic.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
18e83ac75b Btrfs: fix unexpected EEXIST from btrfs_get_extent
This fixes a corner case that is caused by a race of dio write vs dio
read/write.

Here is how the race could happen.

Suppose that no extent map has been loaded into memory yet.
There is a file extent [0, 32K), two jobs are running concurrently
against it, t1 is doing dio write to [8K, 32K) and t2 is doing dio
read from [0, 4K) or [4K, 8K).

t1 goes ahead of t2 and splits em [0, 32K) to em [0K, 8K) and [8K 32K).

------------------------------------------------------
             t1                                t2
      btrfs_get_blocks_direct()         btrfs_get_blocks_direct()
       -> btrfs_get_extent()              -> btrfs_get_extent()
           -> lookup_extent_mapping()
           -> add_extent_mapping()            -> lookup_extent_mapping()
              # load [0, 32K)
       -> btrfs_new_extent_direct()
           -> btrfs_drop_extent_cache()
              # split [0, 32K) and
	      # drop [8K, 32K)
           -> add_extent_mapping()
              # add [8K, 32K)
                                              -> add_extent_mapping()
                                                 # handle -EEXIST when adding
                                                 # [0, 32K)
------------------------------------------------------
About how t2(dio read/write) runs into -EEXIST:

a) add_extent_mapping() gets -EEXIST for adding em [0, 32k),

b) search_extent_mapping() then returns [0, 8k) as the existing em,
   even though start == existing->start, em is [0, 32k) so that
   extent_map_end(em) > extent_map_end(existing), i.e. 32k > 8k,

c) then it goes thru merge_extent_mapping() which tries to add a [8k, 8k)
   (with a length 0) and returns -EEXIST as [8k, 32k) is already in tree,

d) so btrfs_get_extent() ends up returning -EEXIST to dio read/write,
   which is confusing applications.

Here I conclude all the possible situations,
1) start < existing->start

            +-----------+em+-----------+
+--prev---+ |     +-------------+      |
|         | |     |             |      |
+---------+ +     +---+existing++      ++
                +
                |
                +
             start

2) start == existing->start

      +------------em------------+
      |     +-------------+      |
      |     |             |      |
      +     +----existing-+      +
            |
            |
            +
         start

3) start > existing->start && start < (existing->start + existing->len)

      +------------em------------+
      |     +-------------+      |
      |     |             |      |
      +     +----existing-+      +
               |
               |
               +
             start

4) start >= (existing->start + existing->len)

+-----------+em+-----------+
|     +-------------+      | +--next---+
|     |             |      | |         |
+     +---+existing++      + +---------+
                      +
                      |
                      +
                   start

As we can see, it turns out that if start is within existing em (front
inclusive), then the existing em should be returned as is, otherwise,
we try our best to merge candidate em with sibling ems to form a
larger em (in order to reduce the total number of em).

Reported-by: David Vallender <david.vallender@landmark.co.uk>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
a520a7e0b5 Btrfs: fix incorrect block_len in merge_extent_mapping
%block_len could be checked on deciding if two em are mergeable.

merge_extent_mapping() has only added the front pad if the front part
of em gets truncated, but it's possible that the end part gets
truncated.

For both compressed extent and inline extent, em->block_len is not
adjusted accordingly, and for regular extent, em->block_len always
equals to em->len, hence this sets em->block_len with em->len.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Matthew Wilcox
3cbf26da5e btrfs: Remove unused readahead spinlock
The reada_lock in struct btrfs_device was only initialised, and not
actually used.  That's good because there's another lock also called
reada_lock in the btrfs_fs_info that was quite heavily used.  Remove
this one.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
7583d8d088 Btrfs: raid56: fix race between merge_bio and rbio_orig_end_io
Before rbio_orig_end_io() goes to free rbio, rbio may get merged with
more bios from other rbios and rbio->bio_list becomes non-empty,
in that case, these newly merged bios don't end properly.

Once unlock_stripe() is done, rbio->bio_list will not be updated any
more and we can call bio_endio() on all queued bios.

It should only happen in error-out cases, the normal path of recover
and full stripe write have already set RBIO_RMW_LOCKED_BIT to disable
merge before doing IO, so rbio_orig_end_io() called by them doesn't
have the above issue.

Reported-by: Jérôme Carretero <cJ-ko@zougloub.eu>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
44ac474def Btrfs: do not cache rbio pages if using raid6 recover
Since raid6 recover tries all possible combinations of failed stripes,

- when raid6 rebuild algorithm is used, i.e. raid6_datap_recov() and
  raid6_2data_recov(), it may change the in-memory content of failed
  stripes, if such a raid bio is cached, a later raid write rmw or recover
  can steal @stripe_pages from it instead of reading from disks, such that
  it carries the wrong content to do write rmw or recovery and ends up
  with corruption or recovery failures.

- when raid5 rebuild algorithm is used, i.e. xor, raid bio can be cached
  because the only failed stripe which contains @rbio->bio_pages gets
  modified, others remain the same so that their in-memory content is
  consistent with their on-disk content.

This adds a check to skip caching rbio if using raid6 recover.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
0198e5b707 Btrfs: raid56: iterate raid56 internal bio with bio_for_each_segment_all
Bio iterated by set_bio_pages_uptodate() is raid56 internal one, so it
will never be a BIO_CLONED bio, and since this is called by end_io
functions, bio->bi_iter.bi_size is zero, we mustn't use
bio_for_each_segment() as that is a no-op if bi_size is zero.

Fixes: 6592e58c6b ("Btrfs: fix write corruption due to bio cloning on raid5/6")
Cc: <stable@vger.kernel.org> # v4.12-rc6+
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Su Yue
df6703e15c btrfs: correct wrong comment about magic number of index_cnt
There is no function named btrfs_get_inode_index_count.
Explanation for magic number index_cnt=2 in btrfs_new_inode() is
actually located in btrfs_set_inode_index_count().

So replace 'btrfs_get_inode_index_count' in the comment by
'btrfs_set_inode_index_count'.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Nikolay Borisov
d2560ebd23 btrfs: Make btrfs_inode_rsv_release static
It's not used outside of extent-tree so there is no reason to not be
static.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Anand Jain
1c94da9dd9 btrfs: cleanup btrfs_free_stale_device() usage
We call btrfs_free_stale_device() only when we alloc a new struct
btrfs_device (ret=1), so move it closer to where we alloc the new
device. Also drop the comments.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
David Sterba
e2683fc9d2 btrfs: tree-check: reduce stack consumption in check_dir_item
I've noticed that the updated item checker stack consumption increased
dramatically in 542f5385e20cf97447 ("btrfs: tree-checker: Add checker
for dir item")

tree-checker.c:check_leaf                    +552 (176 -> 728)

The array is 255 bytes long, dynamic allocation would slow down the
sanity checks so it's more reasonable to keep it on-stack. Moving the
variable to the scope of use reduces the stack usage again

tree-checker.c:check_leaf                    -264 (728 -> 464)

Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Xiongfeng Wang
6670d4c2d9 btrfs: use correct string length in DEV_INFO ioctl
gcc-8 reports:

fs/btrfs/ioctl.c: In function 'btrfs_ioctl':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' specified
bound 1024 equals destination size [-Wstringop-truncation]

We need one less byte or call strlcpy() to make it a nul-terminated
string. This is done on the next line anyway, but we want to avoid the
warning.

Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Anand Jain
6f794e3c5c btrfs: fail mount when sb flag is not in BTRFS_SUPER_FLAG_SUPP
It appears from the original commit [1] that there isn't any design
specific reason not to fail the mount instead of just warning. This
patch will change it to fail.

[1]
 commit 319e4d0661
    btrfs: Enhance super validation check

Fixes: 319e4d0661 ("btrfs: Enhance super validation check")
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Anand Jain
e2731e5588 btrfs: define SUPER_FLAG_METADUMP_V2
btrfs-progs uses super flag bit BTRFS_SUPER_FLAG_METADUMP_V2 (1ULL << 34).
So just define that in kernel so that we know its been used.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
a6f93c71d4 Btrfs: avoid losing data raid profile when deleting a device
We've avoided data losing raid profile when doing balance, but it
turns out that deleting a device could also result in the same
problem.

Say we have 3 disks, and they're created with '-d raid1' profile.

- We have chunk P (the only data chunk on the empty btrfs).

- Suppose that chunk P's two raid1 copies reside in disk A and disk B.

- Now, 'btrfs device remove disk B'
         btrfs_rm_device()
	   -> btrfs_shrink_device()
	      -> btrfs_relocate_chunk() #relocate any chunk on disk B
	      	 			 to other places.

- Chunk P will be removed and a new chunk will be created to hold
  those data, but as chunk P is the only one holding raid1 profile,
  after it goes away, the new chunk will be created as single profile
  which is our default profile.

This fixes the problem by creating an empty data chunk before
relocating the data chunk.

Metadata/System chunk are supposed to have non-zero bytes all the time
so their raid profile is preserved.

Reported-by: James Alandt <James.Alandt@wdc.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Filipe Manana
81fdf6382b Btrfs: fix space leak after fallocate and zero range operations
If we do a buffered write after a zero range operation that has an
unaligned (with the filesystem's sector size) end which also falls within
an unwritten (prealloc) extent that is currently beyond the inode's
i_size, and the zero range operation has the flag FALLOC_FL_KEEP_SIZE,
we end up leaking data and metadata space. This happens because when
zeroing a range we call btrfs_truncate_block(), which does delalloc
(loads the page and partially zeroes its content), and in the buffered
write path we only clear existing delalloc space reservation for the
range we are writing into if that range starts at an offset smaller then
the inode's i_size, which makes sense since we can not have delalloc
extents beyond the i_size, only unwritten extents are allowed.

Example reproducer:

 $ mkfs.btrfs -f /dev/sdb
 $ mount /dev/sdb /mnt
 $ xfs_io -f -c "falloc -k 428K 4K" /mnt/foobar
 $ xfs_io -c "fzero -k 0 430K" /mnt/foobar
 $ xfs_io -c "pwrite -S 0xaa 428K 4K" /mnt/foobar
 $ umount /mnt

After the unmount we get the metadata and data space leaks reported in
dmesg/syslog:

 [95794.602253] ------------[ cut here ]------------
 [95794.603322] WARNING: CPU: 0 PID: 31496 at fs/btrfs/inode.c:9561 btrfs_destroy_inode+0x4e/0x206 [btrfs]
 [95794.605167] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.613000] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.614448] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.615972] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.617114] RIP: 0010:btrfs_destroy_inode+0x4e/0x206 [btrfs]
 [95794.618001] RSP: 0018:ffffc90001737d00 EFLAGS: 00010202
 [95794.618721] RAX: 0000000000000000 RBX: ffff880070fa1418 RCX: ffffc90001737c7c
 [95794.619645] RDX: 0000000175aa0240 RSI: 0000000000000001 RDI: ffff880070fa1418
 [95794.620711] RBP: ffffc90001737d38 R08: 0000000000000000 R09: 0000000000000000
 [95794.621932] R10: ffffc90001737c48 R11: ffff88007123e158 R12: ffff880075b6a000
 [95794.623124] R13: ffff88006145c000 R14: ffff880070fa1418 R15: ffff880070c3b4a0
 [95794.624188] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.625578] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.626522] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95794.627647] Call Trace:
 [95794.628128]  destroy_inode+0x3d/0x55
 [95794.628573]  evict+0x177/0x17e
 [95794.629010]  dispose_list+0x50/0x71
 [95794.629478]  evict_inodes+0x132/0x141
 [95794.630289]  generic_shutdown_super+0x3f/0x10b
 [95794.630864]  kill_anon_super+0x12/0x1c
 [95794.631383]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95794.631930]  deactivate_locked_super+0x30/0x68
 [95794.632539]  deactivate_super+0x36/0x39
 [95794.633200]  cleanup_mnt+0x49/0x67
 [95794.633818]  __cleanup_mnt+0x12/0x14
 [95794.634416]  task_work_run+0x82/0xa6
 [95794.634902]  prepare_exit_to_usermode+0xe1/0x10c
 [95794.635525]  syscall_return_slowpath+0x18c/0x1af
 [95794.636122]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95794.636834] RIP: 0033:0x7fa678cb99a7
 [95794.637370] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95794.638672] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95794.639596] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95794.640703] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95794.641773] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95794.643150] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95794.644249] Code: ff 4c 8b a8 80 06 00 00 48 8b 87 c0 01 00 00 48 85 c0 74 02 0f ff 48 83 bb e0 02 00 00 00 74 02 0f ff 83 bb 3c ff ff ff 00 74 02 <0f> ff 83 bb 40 ff ff ff 00 74 02 0f ff 48 83 bb f8 fe ff ff 00
 [95794.646929] ---[ end trace e95877675c6ec007 ]---
 [95794.647751] ------------[ cut here ]------------
 [95794.648509] WARNING: CPU: 0 PID: 31496 at fs/btrfs/inode.c:9562 btrfs_destroy_inode+0x59/0x206 [btrfs]
 [95794.649842] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.654659] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.655894] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.657546] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.658433] RIP: 0010:btrfs_destroy_inode+0x59/0x206 [btrfs]
 [95794.659279] RSP: 0018:ffffc90001737d00 EFLAGS: 00010202
 [95794.660054] RAX: 0000000000000000 RBX: ffff880070fa1418 RCX: ffffc90001737c7c
 [95794.660753] RDX: 0000000175aa0240 RSI: 0000000000000001 RDI: ffff880070fa1418
 [95794.661513] RBP: ffffc90001737d38 R08: 0000000000000000 R09: 0000000000000000
 [95794.662289] R10: ffffc90001737c48 R11: ffff88007123e158 R12: ffff880075b6a000
 [95794.663393] R13: ffff88006145c000 R14: ffff880070fa1418 R15: ffff880070c3b4a0
 [95794.664342] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.665673] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.666593] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95794.667629] Call Trace:
 [95794.668065]  destroy_inode+0x3d/0x55
 [95794.668637]  evict+0x177/0x17e
 [95794.669179]  dispose_list+0x50/0x71
 [95794.669830]  evict_inodes+0x132/0x141
 [95794.670416]  generic_shutdown_super+0x3f/0x10b
 [95794.671103]  kill_anon_super+0x12/0x1c
 [95794.671786]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95794.672552]  deactivate_locked_super+0x30/0x68
 [95794.673393]  deactivate_super+0x36/0x39
 [95794.674107]  cleanup_mnt+0x49/0x67
 [95794.674706]  __cleanup_mnt+0x12/0x14
 [95794.675279]  task_work_run+0x82/0xa6
 [95794.675795]  prepare_exit_to_usermode+0xe1/0x10c
 [95794.676507]  syscall_return_slowpath+0x18c/0x1af
 [95794.677275]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95794.678006] RIP: 0033:0x7fa678cb99a7
 [95794.678600] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95794.679739] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95794.680779] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95794.681837] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95794.682867] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95794.683891] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95794.684843] Code: c0 01 00 00 48 85 c0 74 02 0f ff 48 83 bb e0 02 00 00 00 74 02 0f ff 83 bb 3c ff ff ff 00 74 02 0f ff 83 bb 40 ff ff ff 00 74 02 <0f> ff 48 83 bb f8 fe ff ff 00 74 02 0f ff 48 83 bb 00 ff ff ff
 [95794.687156] ---[ end trace e95877675c6ec008 ]---
 [95794.687876] ------------[ cut here ]------------
 [95794.688579] WARNING: CPU: 0 PID: 31496 at fs/btrfs/inode.c:9565 btrfs_destroy_inode+0x7d/0x206 [btrfs]
 [95794.689735] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.695015] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.696396] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.697956] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.698925] RIP: 0010:btrfs_destroy_inode+0x7d/0x206 [btrfs]
 [95794.699763] RSP: 0018:ffffc90001737d00 EFLAGS: 00010206
 [95794.700434] RAX: 0000000000000000 RBX: ffff880070fa1418 RCX: ffffc90001737c7c
 [95794.701445] RDX: 0000000175aa0240 RSI: 0000000000000001 RDI: ffff880070fa1418
 [95794.702448] RBP: ffffc90001737d38 R08: 0000000000000000 R09: 0000000000000000
 [95794.703557] R10: ffffc90001737c48 R11: ffff88007123e158 R12: ffff880075b6a000
 [95794.704441] R13: ffff88006145c000 R14: ffff880070fa1418 R15: ffff880070c3b4a0
 [95794.705270] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.706341] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.707001] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95794.708030] Call Trace:
 [95794.708466]  destroy_inode+0x3d/0x55
 [95794.709071]  evict+0x177/0x17e
 [95794.709497]  dispose_list+0x50/0x71
 [95794.709973]  evict_inodes+0x132/0x141
 [95794.710564]  generic_shutdown_super+0x3f/0x10b
 [95794.711200]  kill_anon_super+0x12/0x1c
 [95794.711633]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95794.712139]  deactivate_locked_super+0x30/0x68
 [95794.712608]  deactivate_super+0x36/0x39
 [95794.713093]  cleanup_mnt+0x49/0x67
 [95794.713514]  __cleanup_mnt+0x12/0x14
 [95794.713933]  task_work_run+0x82/0xa6
 [95794.714543]  prepare_exit_to_usermode+0xe1/0x10c
 [95794.715247]  syscall_return_slowpath+0x18c/0x1af
 [95794.715952]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95794.716653] RIP: 0033:0x7fa678cb99a7
 [95794.721100] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95794.722052] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95794.722856] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95794.723698] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95794.724736] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95794.725928] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95794.726728] Code: 40 ff ff ff 00 74 02 0f ff 48 83 bb f8 fe ff ff 00 74 02 0f ff 48 83 bb 00 ff ff ff 00 74 02 0f ff 48 83 bb 30 ff ff ff 00 74 02 <0f> ff 48 83 bb 08 ff ff ff 00 74 02 0f ff 4d 85 e4 0f 84 52 01
 [95794.729203] ---[ end trace e95877675c6ec009 ]---
 [95794.841054] ------------[ cut here ]------------
 [95794.841829] WARNING: CPU: 0 PID: 31496 at fs/btrfs/extent-tree.c:5831 btrfs_free_block_groups+0x235/0x36a [btrfs]
 [95794.843425] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.850658] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.852590] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.854752] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.855812] RIP: 0010:btrfs_free_block_groups+0x235/0x36a [btrfs]
 [95794.856811] RSP: 0018:ffffc90001737d70 EFLAGS: 00010206
 [95794.857805] RAX: 0000000080000000 RBX: ffff88006145c000 RCX: 0000000000000001
 [95794.859014] RDX: 00000001810af668 RSI: 0000000000000002 RDI: 00000000ffffffff
 [95794.860270] RBP: ffffc90001737d98 R08: 0000000000000000 R09: ffffffff817e22b9
 [95794.861525] R10: ffffc90001737c80 R11: 00000000000337fd R12: 0000000000000000
 [95794.862700] R13: ffff88006145c0c0 R14: ffff88021b61a800 R15: ffff88006145c100
 [95794.863810] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.865149] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.866099] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95794.867198] Call Trace:
 [95794.867626]  close_ctree+0x1db/0x2b8 [btrfs]
 [95794.868188]  ? evict_inodes+0x132/0x141
 [95794.869037]  btrfs_put_super+0x15/0x17 [btrfs]
 [95794.870400]  generic_shutdown_super+0x6a/0x10b
 [95794.871262]  kill_anon_super+0x12/0x1c
 [95794.872046]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95794.872746]  deactivate_locked_super+0x30/0x68
 [95794.873687]  deactivate_super+0x36/0x39
 [95794.874639]  cleanup_mnt+0x49/0x67
 [95794.875504]  __cleanup_mnt+0x12/0x14
 [95794.876126]  task_work_run+0x82/0xa6
 [95794.876788]  prepare_exit_to_usermode+0xe1/0x10c
 [95794.877777]  syscall_return_slowpath+0x18c/0x1af
 [95794.878381]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95794.878888] RIP: 0033:0x7fa678cb99a7
 [95794.879307] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95794.880204] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95794.881640] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95794.882690] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95794.883538] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95794.884562] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95794.885664] Code: 89 ef e8 07 ec 32 e1 e8 9d c0 ea e0 48 8d b3 28 02 00 00 48 83 c9 ff 31 d2 48 89 df e8 29 c5 ff ff 48 83 bb 80 02 00 00 00 74 02 <0f> ff 48 83 bb 88 02 00 00 00 74 02 0f ff 48 83 bb d8 02 00 00
 [95794.887980] ---[ end trace e95877675c6ec00a ]---
 [95794.888739] ------------[ cut here ]------------
 [95794.889405] WARNING: CPU: 0 PID: 31496 at fs/btrfs/extent-tree.c:5832 btrfs_free_block_groups+0x241/0x36a [btrfs]
 [95794.891020] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.897551] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.898509] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.899685] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.900592] RIP: 0010:btrfs_free_block_groups+0x241/0x36a [btrfs]
 [95794.901387] RSP: 0018:ffffc90001737d70 EFLAGS: 00010206
 [95794.902300] RAX: 0000000080000000 RBX: ffff88006145c000 RCX: 0000000000000001
 [95794.903260] RDX: 00000001810af668 RSI: 0000000000000002 RDI: 00000000ffffffff
 [95794.904332] RBP: ffffc90001737d98 R08: 0000000000000000 R09: ffffffff817e22b9
 [95794.905300] R10: ffffc90001737c80 R11: 00000000000337fd R12: 0000000000000000
 [95794.906439] R13: ffff88006145c0c0 R14: ffff88021b61a800 R15: ffff88006145c100
 [95794.907459] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.908625] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.909511] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95794.910630] Call Trace:
 [95794.911153]  close_ctree+0x1db/0x2b8 [btrfs]
 [95794.911837]  ? evict_inodes+0x132/0x141
 [95794.912344]  btrfs_put_super+0x15/0x17 [btrfs]
 [95794.912975]  generic_shutdown_super+0x6a/0x10b
 [95794.913788]  kill_anon_super+0x12/0x1c
 [95794.914424]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95794.915142]  deactivate_locked_super+0x30/0x68
 [95794.915831]  deactivate_super+0x36/0x39
 [95794.916433]  cleanup_mnt+0x49/0x67
 [95794.917045]  __cleanup_mnt+0x12/0x14
 [95794.917665]  task_work_run+0x82/0xa6
 [95794.918309]  prepare_exit_to_usermode+0xe1/0x10c
 [95794.919021]  syscall_return_slowpath+0x18c/0x1af
 [95794.919722]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95794.920426] RIP: 0033:0x7fa678cb99a7
 [95794.921039] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95794.922303] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95794.923335] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95794.924364] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95794.925435] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95794.926533] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95794.927557] Code: 48 8d b3 28 02 00 00 48 83 c9 ff 31 d2 48 89 df e8 29 c5 ff ff 48 83 bb 80 02 00 00 00 74 02 0f ff 48 83 bb 88 02 00 00 00 74 02 <0f> ff 48 83 bb d8 02 00 00 00 74 02 0f ff 48 83 bb e0 02 00 00
 [95794.930166] ---[ end trace e95877675c6ec00b ]---
 [95794.930961] ------------[ cut here ]------------
 [95794.931727] WARNING: CPU: 0 PID: 31496 at fs/btrfs/extent-tree.c:9953 btrfs_free_block_groups+0x2bc/0x36a [btrfs]
 [95794.932729] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.938394] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.939842] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.941455] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.942336] RIP: 0010:btrfs_free_block_groups+0x2bc/0x36a [btrfs]
 [95794.943268] RSP: 0018:ffffc90001737d70 EFLAGS: 00010206
 [95794.944127] RAX: ffff8802004fd0e8 RBX: ffff88006145c000 RCX: 0000000000000001
 [95794.945211] RDX: 00000001810af668 RSI: 0000000000000002 RDI: 00000000ffffffff
 [95794.946316] RBP: ffffc90001737d98 R08: 0000000000000000 R09: ffffffff817e22b9
 [95794.947271] R10: ffffc90001737c80 R11: 00000000000337fd R12: ffff8802004fd0e8
 [95794.948219] R13: ffff88006145c0c0 R14: ffff88006145e598 R15: ffff88006145c100
 [95794.949193] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.950495] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.951338] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95794.952361] Call Trace:
 [95794.952811]  close_ctree+0x1db/0x2b8 [btrfs]
 [95794.953522]  ? evict_inodes+0x132/0x141
 [95794.954543]  btrfs_put_super+0x15/0x17 [btrfs]
 [95794.955231]  generic_shutdown_super+0x6a/0x10b
 [95794.955916]  kill_anon_super+0x12/0x1c
 [95794.956414]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95794.956953]  deactivate_locked_super+0x30/0x68
 [95794.957635]  deactivate_super+0x36/0x39
 [95794.958256]  cleanup_mnt+0x49/0x67
 [95794.958701]  __cleanup_mnt+0x12/0x14
 [95794.959181]  task_work_run+0x82/0xa6
 [95794.959635]  prepare_exit_to_usermode+0xe1/0x10c
 [95794.960182]  syscall_return_slowpath+0x18c/0x1af
 [95794.960731]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95794.961438] RIP: 0033:0x7fa678cb99a7
 [95794.961990] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95794.963111] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95794.963975] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95794.964680] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95794.965763] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95794.966868] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95794.967800] Code: 00 00 00 4c 8b a3 98 25 00 00 49 83 bc 24 60 ff ff ff 00 75 16 49 83 bc 24 68 ff ff ff 00 75 0b 49 83 bc 24 70 ff ff ff 00 74 16 <0f> ff 49 8d b4 24 18 ff ff ff 31 c9 31 d2 48 89 df e8 93 7a ff
 [95794.970629] ---[ end trace e95877675c6ec00c ]---
 [95794.971451] BTRFS info (device sdi): space_info 1 has 7680000 free, is not full
 [95794.972351] BTRFS info (device sdi): space_info total=8388608, used=704512, pinned=0, reserved=0, may_use=4096, readonly=0
 [95794.973595] ------------[ cut here ]------------
 [95794.974353] WARNING: CPU: 0 PID: 31496 at fs/btrfs/extent-tree.c:9953 btrfs_free_block_groups+0x2bc/0x36a [btrfs]
 [95794.980163] Modules linked in: btrfs xfs ppdev ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper parport_pc psmouse sg i2c_piix4 parport i2c_core evdev pcspkr button serio_raw sunrpc loop autofs4 ext4 crc16 mbcache jbd2 zstd_decompress zstd_compress xxhash raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod virtio_scsi ata_generic crc32c_intel ata_piix floppy virtio_pci virtio_ring virtio libata scsi_mod e1000 [last unloaded: btrfs]
 [95794.986461] CPU: 0 PID: 31496 Comm: umount Tainted: G        W       4.14.0-rc6-btrfs-next-54+ #1
 [95794.987591] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
 [95794.988929] task: ffff880075aa0240 task.stack: ffffc90001734000
 [95794.989922] RIP: 0010:btrfs_free_block_groups+0x2bc/0x36a [btrfs]
 [95794.990715] RSP: 0018:ffffc90001737d70 EFLAGS: 00010206
 [95794.991431] RAX: ffff88020f6e70e8 RBX: ffff88006145c000 RCX: ffffffff8115a906
 [95794.992455] RDX: ffffffff8115a902 RSI: ffff880075aa0b40 RDI: ffff880075aa0b40
 [95794.993535] RBP: ffffc90001737d98 R08: 0000000000000020 R09: fffffffffffffff7
 [95794.994573] R10: 00000000ffffffc4 R11: ffff8800633b1bc0 R12: ffff88020f6e70e8
 [95794.996250] R13: 0000000000000038 R14: ffff88006145e598 R15: 0000000000000000
 [95794.997233] FS:  00007fa6793c92c0(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000
 [95794.998592] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [95794.999484] CR2: 000056338670d048 CR3: 00000000610dc005 CR4: 00000000001606f0
 [95795.000542] Call Trace:
 [95795.001138]  close_ctree+0x1db/0x2b8 [btrfs]
 [95795.001885]  ? evict_inodes+0x132/0x141
 [95795.002407]  btrfs_put_super+0x15/0x17 [btrfs]
 [95795.003093]  generic_shutdown_super+0x6a/0x10b
 [95795.003720]  kill_anon_super+0x12/0x1c
 [95795.004353]  btrfs_kill_super+0x16/0x21 [btrfs]
 [95795.005095]  deactivate_locked_super+0x30/0x68
 [95795.005716]  deactivate_super+0x36/0x39
 [95795.006388]  cleanup_mnt+0x49/0x67
 [95795.006939]  __cleanup_mnt+0x12/0x14
 [95795.007512]  task_work_run+0x82/0xa6
 [95795.008124]  prepare_exit_to_usermode+0xe1/0x10c
 [95795.008994]  syscall_return_slowpath+0x18c/0x1af
 [95795.009831]  entry_SYSCALL_64_fastpath+0xab/0xad
 [95795.010610] RIP: 0033:0x7fa678cb99a7
 [95795.011193] RSP: 002b:00007ffccf0aaed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [95795.012327] RAX: 0000000000000000 RBX: 0000563386706030 RCX: 00007fa678cb99a7
 [95795.013432] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000056338670ca90
 [95795.014558] RBP: 000056338670ca90 R08: 000056338670c740 R09: 0000000000000015
 [95795.015577] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fa6791bae64
 [95795.016569] R13: 0000000000000000 R14: 0000563386706210 R15: 00007ffccf0ab160
 [95795.017662] Code: 00 00 00 4c 8b a3 98 25 00 00 49 83 bc 24 60 ff ff ff 00 75 16 49 83 bc 24 68 ff ff ff 00 75 0b 49 83 bc 24 70 ff ff ff 00 74 16 <0f> ff 49 8d b4 24 18 ff ff ff 31 c9 31 d2 48 89 df e8 93 7a ff
 [95795.020538] ---[ end trace e95877675c6ec00d ]---
 [95795.021259] BTRFS info (device sdi): space_info 4 has 1072775168 free, is not full
 [95795.022390] BTRFS info (device sdi): space_info total=1073741824, used=114688, pinned=0, reserved=0, may_use=786432, readonly=65536

Fix this by ensuring the zero range operation does not call
btrfs_truncate_block() if the corresponding extent is an unwritten one
(it's pointless anyway, since reading from an unwritten extent yields
zeroes).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Filipe Manana
9f13ce743b Btrfs: fix missing inode i_size update after zero range operation
For a fallocate's zero range operation that targets a range with an end
that is not aligned to the sector size, we can end up not updating the
inode's i_size. This happens when the last page of the range maps to an
unwritten (prealloc) extent and before that last page we have either a
hole or a written extent. This is because in this scenario we relied
on a call to btrfs_prealloc_file_range() to update the inode's i_size,
however it can only update the i_size to the "down aligned" end of the
range.

Example:

 $ mkfs.btrfs -f /dev/sdc
 $ mount /dev/sdc /mnt
 $ xfs_io -f -c "pwrite -S 0xff 0 428K" /mnt/foobar
 $ xfs_io -c "falloc -k 428K 4K" /mnt/foobar
 $ xfs_io -c "fzero 0 430K" /mnt/foobar
 $ du --bytes /mnt/foobar
 438272	/mnt/foobar

The inode's i_size was left as 428Kb (438272 bytes) when it should have
been updated to 430Kb (440320 bytes).
Fix this by always updating the inode's i_size explicitly after zeroing
the range.

Fixes: ba6d5887946ff86d93dc ("Btrfs: add support for fallocate's zero range operation")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Filipe Manana
94f450712a Btrfs: use cached state when dirtying pages during buffered write
During a buffered IO write, we can have an extent state that we got when
we locked the range (if the range starts at an offset lower than eof), so
always pass it to btrfs_dirty_pages() so that setting the delalloc bit
in the range does not need to do a full search in the inode's io tree,
saving time and reducing the amount of time we hold the io tree's lock.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Filipe Manana
f27451f229 Btrfs: add support for fallocate's zero range operation
This implements support the zero range operation of fallocate. For now
at least it's as simple as possible while reusing most of the existing
fallocate and hole punching infrastructure.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Liu Bo
cc54ff626a Btrfs: do not merge rbios if their fail stripe index are not identical
Since fail stripe index in rbio would be used to decide which
algorithm reconstruction would be run, we cannot merge rbios if
their's fail striped indexes are different, otherwise, one of the two
reconstructions would fail.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Liu Bo
db34be19c4 Btrfs: remove redundant check in rbio_can_merge
Given the above
'
if (last->operation != cur->operation)
	return 0;
',
it's guaranteed that two operations are same.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Anand Jain
05a5c55dfc btrfs: minor style cleanups in btrfs_scan_one_device
Assign ret = -EINVAL where it is actually required.
Remove { } around single line if else code.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Anand Jain
c1f32b7c1f btrfs: simplify mutex unlocking code in btrfs_commit_transaction
No functional change rearrange the mutex_unlock.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ edit subject ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Anand Jain
cadbc0a067 btrfs: rename btrfs_device::scrub_device to scrub_ctx
btrfs_device::scrub_device is not a device which is being scrubbed,
but it holds the scrub context, so rename to reflect the same. No
functional changes here.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00