diff options
| author | David Sterba <dsterba@suse.com> | 2018-06-19 17:09:47 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-15 09:46:55 +0200 |
| commit | 122fe306d072fbd2e9cce5c89dc34c17da04f3ba (patch) | |
| tree | 1f0c30c9aaf00bcee8ec2b8262ef4220b8f755f6 /fs | |
| parent | f88b40c1472a3691a942b9e397e62d3be560ad0f (diff) | |
btrfs: lift uuid_mutex to callers of btrfs_open_devices
[ Upstream commit f5194e34cabaddd348a90f950e0a8188dd26cdc0 ]
Prepartory work to fix race between mount and device scan.
The callers will have to manage the critical section, eg. mount wants to
scan and then call btrfs_open_devices without the ioctl scan walking in
and modifying the fs devices in the meantime.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/super.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/volumes.c | 4 |
2 files changed, 4 insertions, 2 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index bddfc28b27c0..6eb789a529a3 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1565,7 +1565,9 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, goto error_fs_info; } + mutex_lock(&uuid_mutex); error = btrfs_open_devices(fs_devices, mode, fs_type); + mutex_unlock(&uuid_mutex); if (error) goto error_fs_info; diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index fca57c1f077c..0bd8c544d2de 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1146,7 +1146,8 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, { int ret; - mutex_lock(&uuid_mutex); + lockdep_assert_held(&uuid_mutex); + mutex_lock(&fs_devices->device_list_mutex); if (fs_devices->opened) { fs_devices->opened++; @@ -1156,7 +1157,6 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, ret = open_fs_devices(fs_devices, flags, holder); } mutex_unlock(&fs_devices->device_list_mutex); - mutex_unlock(&uuid_mutex); return ret; } |