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: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NQu Wenruo <wqu@suse.com>
[ error message adjustments ]
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: f32e48e9 ("Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots")
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: 703c88e0 ("Btrfs: fix tracking of orphan inode count")
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

This regression is introduced in
commit 3d48d981 ("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 3d48d981 ("btrfs: Handle uninitialised inode eviction")
Cc: <stable@vger.kernel.org> # v4.7-rc6+
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: 681ae509 ("Btrfs: cleanup reserved space when freeing tree log on error")
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

@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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

As struct btrfs_disk_super is being passed, so it can get devid
the same way its parent does.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Commit 60999ca4 ("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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

No functional changes.
Rename btrfs_free_stale_devices() arg to skip_dev, so that it
reflects what that arg for.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

This updates btrfs_free_stale_devices() helper function to delete all
unmouted devices, when arg is NULL.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

No functional changes, just makes the code more readable
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NQu Wenruo <wqu@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
[ minor string adjustments ]
Signed-off-by: NDavid Sterba <dsterba@suse.com>

These helpers are extent map specific, move them to extent_map.c.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

This is a prepare work for the following extent map selftest, which
runs tests against em merge logic.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NDavid Vallender <david.vallender@landmark.co.uk>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

%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: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NMatthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NJérôme Carretero <cJ-ko@zougloub.eu>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: 6592e58c ("Btrfs: fix write corruption due to bio cloning on raid5/6")
Cc: <stable@vger.kernel.org> # v4.12-rc6+
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NSu Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

It's not used outside of extent-tree so there is no reason to not be
static.
Signed-off-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NJosef Bacik <jbacik@fb.com>
Reviewed-by: NQu Wenruo <wqu@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NXiongfeng Wang <xiongfeng.wang@linaro.org>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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 319e4d06
    btrfs: Enhance super validation check

Fixes: 319e4d06 ("btrfs: Enhance super validation check")
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NQu Wenruo <wqu@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

The UUID change by btrfstune sets SUPER_FLAG_CHANGING_FSID and resets it
only when changing fsid is complete. Its not a good idea to mount the
device anything in between, reading metadata blocks would fail with UUID
mismatch.

This patch doesn't add SUPER_FLAG_CHANGING_FSID into
BTRFS_SUPER_FLAG_SUPP list, so mount will fail (along with the fix in
the next patch) when SUPER_FLAG_CHANGING_FSID is set.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NQu Wenruo <wqu@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NJames Alandt <James.Alandt@wdc.com>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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: NFilipe Manana <fdmanana@suse.com>
Tested-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>