diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 245952c..f65b258 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -36,7 +36,7 @@
 extern struct kmem_cache *btrfs_bit_radix_cachep;
 extern struct kmem_cache *btrfs_path_cachep;
 
-#define BTRFS_MAGIC "_B2RfS_M"
+#define BTRFS_MAGIC "_B3RfS_M"
 
 #define BTRFS_MAX_LEVEL 8
 #define BTRFS_ROOT_TREE_OBJECTID 1ULL