diff --git a/fs/internal.h b/fs/internal.h
index 839d3f9..7b1cb15 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -78,6 +78,7 @@
 extern bool grab_super_passive(struct super_block *sb);
 extern struct dentry *mount_fs(struct file_system_type *,
 			       int, const char *, void *);
+extern struct super_block *user_get_super(dev_t);
 
 /*
  * open.c