Btrfs: fix mutex unlock without prior lock on space cache truncation
If the call to btrfs_truncate_inode_items() failed and we don't have a block
group, we were unlocking the cache_write_mutex without having locked it (we
do it only if we have a block group).
Fixes: 1bbc621ef284 ("Btrfs: allow block group cache writeout
outside critical section in commit")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 9dbe5b5..fb5a6b1 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -231,6 +231,7 @@
{
int ret = 0;
struct btrfs_path *path = btrfs_alloc_path();
+ bool locked = false;
if (!path) {
ret = -ENOMEM;
@@ -238,6 +239,7 @@
}
if (block_group) {
+ locked = true;
mutex_lock(&trans->transaction->cache_write_mutex);
if (!list_empty(&block_group->io_list)) {
list_del_init(&block_group->io_list);
@@ -269,18 +271,14 @@
*/
ret = btrfs_truncate_inode_items(trans, root, inode,
0, BTRFS_EXTENT_DATA_KEY);
- if (ret) {
- mutex_unlock(&trans->transaction->cache_write_mutex);
- btrfs_abort_transaction(trans, root, ret);
- return ret;
- }
+ if (ret)
+ goto fail;
ret = btrfs_update_inode(trans, root, inode);
- if (block_group)
- mutex_unlock(&trans->transaction->cache_write_mutex);
-
fail:
+ if (locked)
+ mutex_unlock(&trans->transaction->cache_write_mutex);
if (ret)
btrfs_abort_transaction(trans, root, ret);