1 files changed, 1 insertions, 0 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0f2a9b584fb6..166896dd44c2 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -580,6 +580,7 @@ struct btrfs_block_group_cache {
         struct btrfs_block_group_item item;
         spinlock_t lock;
         struct mutex alloc_mutex;
+        struct mutex cache_mutex;
         u64 pinned;
         u64 reserved;
         u64 flags;