[PATCH 5/5] btrfs: move uuid_mutex closer to exclusivity

[Anand Jain <anand.jain@oracle.com>]

move uuid_mutex with in device_list_add().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
 fs/btrfs/volumes.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index f942e8193862..283417bf3b00 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -740,6 +740,7 @@ static noinline int device_list_add(const char *path,
 	u64 found_transid = btrfs_super_generation(disk_super);
 	u64 devid = btrfs_stack_device_id(&disk_super->dev_item);
 
+	mutex_lock(&uuid_mutex);
 	fs_devices = find_fsid(disk_super->fsid);
 	if (!fs_devices) {
 		fs_devices = alloc_fs_devices(disk_super->fsid);
@@ -847,6 +848,8 @@ static noinline int device_list_add(const char *path,
 
 	fs_devices->total_devices = btrfs_super_num_devices(disk_super);
 
+	mutex_unlock(&uuid_mutex);
+
 	*device_ret = device;
 
 	return 0;
@@ -1208,9 +1211,7 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
 		goto error_bdev_put;
 	}
 
-	mutex_lock(&uuid_mutex);
 	ret = device_list_add(path, disk_super, &device);
-	mutex_unlock(&uuid_mutex);
 
 	*fs_devices_ret = device->fs_devices;
 
-- 
2.7.0