diff mbox series

[13/16] btrfs: cleanup btrfs_remove_chunk

Message ID 731ff89d22332c3e344f9ea4ca28012f01d50656.1599234146.git.anand.jain@oracle.com (mailing list archive)
State New, archived
Headers show
Series btrfs: seed fix null ptr, use only main device_list_mutex, and cleanups | expand

Commit Message

Anand Jain Sept. 4, 2020, 5:34 p.m. UTC 
In the function btrfs_remove_chunk() remove the local variable
%fs_devices, instead use the assigned pointer directly.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
---
 fs/btrfs/volumes.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

Comments

David Sterba Sept. 9, 2020, 10:50 a.m. UTC | #1 
On Sat, Sep 05, 2020 at 01:34:33AM +0800, Anand Jain wrote:
> In the function btrfs_remove_chunk() remove the local variable
> %fs_devices, instead use the assigned pointer directly.

Local variable that caches some pointer is ok if it's used multiple
time, this patch does the opposite.
Anand Jain Sept. 9, 2020, 11:15 a.m. UTC | #2 
On 9/9/20 6:50 pm, David Sterba wrote:
> On Sat, Sep 05, 2020 at 01:34:33AM +0800, Anand Jain wrote:
>> In the function btrfs_remove_chunk() remove the local variable
>> %fs_devices, instead use the assigned pointer directly.
> 
> Local variable that caches some pointer is ok if it's used multiple
> time, this patch does the opposite.
> 

Oh. By this, it was easy to find and confirm that the device_list_mutex
is of the main device fs_info->fs_deices. I should have mentioned that
in the changelog.

Thanks, Anand
diff mbox series

Patch

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index f70b79eaa76d..f16c4a854a6c 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2922,7 +2922,6 @@  int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
 	struct map_lookup *map;
 	u64 dev_extent_len = 0;
 	int i, ret = 0;
-	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 
 	em = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
 	if (IS_ERR(em)) {
@@ -2944,14 +2943,14 @@  int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
 	 * a device replace operation that replaces the device object associated
 	 * with map stripes (dev-replace.c:btrfs_dev_replace_finishing()).
 	 */
-	mutex_lock(&fs_devices->device_list_mutex);
+	mutex_lock(&fs_info->fs_devices->device_list_mutex);
 	for (i = 0; i < map->num_stripes; i++) {
 		struct btrfs_device *device = map->stripes[i].dev;
 		ret = btrfs_free_dev_extent(trans, device,
 					    map->stripes[i].physical,
 					    &dev_extent_len);
 		if (ret) {
-			mutex_unlock(&fs_devices->device_list_mutex);
+			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
 			btrfs_abort_transaction(trans, ret);
 			goto out;
 		}
@@ -2967,12 +2966,12 @@  int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
 
 		ret = btrfs_update_device(trans, device);
 		if (ret) {
-			mutex_unlock(&fs_devices->device_list_mutex);
+			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
 			btrfs_abort_transaction(trans, ret);
 			goto out;
 		}
 	}
-	mutex_unlock(&fs_devices->device_list_mutex);
+	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
 
 	ret = btrfs_free_chunk(trans, chunk_offset);
 	if (ret) {