btrfs: call mnt_drop_write after interrupted subvol deletion
authorDavid Sterba <dsterba@suse.cz>
Fri, 6 Dec 2013 16:51:32 +0000 (17:51 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 20 Dec 2013 15:49:03 +0000 (07:49 -0800)
commit5efc91cb9ff638c11ae3fd9c6b810b6d1940a1a1
treea783ef3b1050a12651db90851a185f7ccb3ca424
parent93ecac1d5fad38f8a04e9bcdfaa181ad8ff23681
btrfs: call mnt_drop_write after interrupted subvol deletion

commit e43f998e47bae27e37e159915625e8d4b130153b upstream.

If btrfs_ioctl_snap_destroy blocks on the mutex and the process is
killed, mnt_write count is unbalanced and leads to unmountable
filesystem.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/btrfs/ioctl.c