diff --git a/fs/dcookies.c b/fs/dcookies.c
index c1208f5..792cbf5 100644
--- a/fs/dcookies.c
+++ b/fs/dcookies.c
@@ -20,6 +20,7 @@
 #include <linux/capability.h>
 #include <linux/dcache.h>
 #include <linux/mm.h>
+#include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/dcookies.h>
 #include <linux/mutex.h>