diff --git a/include/linux/quota.h b/include/linux/quota.h
index c09fa04..84e9be7 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -75,6 +75,7 @@
 #define	QFMT_VFS_V0 2
 #define QFMT_OCFS2 3
 #define	QFMT_VFS_V1 4
+#define QFMT_NS	5
 
 /* Size of block in which space limits are passed through the quota
  * interface */