diff --git a/fs/super.c b/fs/super.c
index a5a4aca..453877c 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -117,7 +117,7 @@
  * Drop a superblock's refcount.  Returns non-zero if the superblock was
  * destroyed.  The caller must hold sb_lock.
  */
-int __put_super(struct super_block *sb)
+static int __put_super(struct super_block *sb)
 {
 	int ret = 0;