diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 41cf893..84326e9 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -32,6 +32,8 @@
 	OP_CB_WANTS_CANCELLED = 12,
 	OP_CB_NOTIFY_LOCK   = 13,
 	OP_CB_NOTIFY_DEVICEID = 14,
+/* Callback operations new to NFSv4.2 */
+	OP_CB_OFFLOAD = 15,
 	OP_CB_ILLEGAL = 10044,
 };