diff --git a/fs/orangefs/protocol.h b/fs/orangefs/protocol.h
index 03bbe7505a35661644991357a26e10ca70987c6b..56dd65abb9080719dd9e58b79c84674b95c73bda 100644
--- a/fs/orangefs/protocol.h
+++ b/fs/orangefs/protocol.h
@@ -399,6 +399,7 @@ enum {
  * space. Zero signifies the upstream version of the kernel module.
  */
 #define ORANGEFS_KERNEL_PROTO_VERSION 0
+#define ORANGEFS_MINIMUM_USERSPACE_VERSION 20904
 
 /*
  * describes memory regions to map in the ORANGEFS_DEV_MAP ioctl.