btrfs: fix leaking BTRFS_FS_STATE_REMOUNTING flag

[BUG]
The following script can lead to unexpected qgroup rescan failure:

  # mkfs.btrfs -f -O quota $dev
  # mount $dev $mnt
  # mount -o remount,rescue=ibadroots $mnt
    ^^^^^ This above command is expected to fail

  # btrfs quota rescan -w $mnt
    ^^^^^ The above qgroup rescan is not expected to fail

  # btrfs qgroup show $mnt
  WARNING: qgroup data inconsistent, rescan recommended
  Qgroupid    Referenced    Exclusive   Path
  --------    ----------    ---------   ----
  0/5           16.00KiB     16.00KiB   <toplevel>

The above short script will be converted to a proper fstests case.

[CAUSE]
Inside btrfs_reconfigure(), if either btrfs_check_options() or
btrfs_check_features() failed, we will always have
BTRFS_FS_STATE_REMOUNTING set for the fs until the next successful
remount.

That BTRFS_FS_STATE_REMOUNTING flag will interrupt several operations,
including:

- Qgroup rescan
- Auto defrag
- Space reclaim

[FIX]
Change the error handling of btrfs_check_options() and
btrfs_check_features() to goto restore label.

Fixes: eddb1a433f26 ("btrfs: add reconfigure callback for fs_context")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

0 files changed, 0 insertions, 0 deletions