diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 35fa4d5..4a7ae8a 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -396,4 +396,23 @@
 
 #define	RPC_MAX_ADDRBUFLEN	(63U)
 
+/*
+ * When we want to reduce the size of the reserved space in the response
+ * buffer, we need to take into account the size of any checksum data that
+ * may be at the end of the packet. This is difficult to determine exactly
+ * for all cases without actually generating the checksum, so we just use a
+ * static value.
+ */
+static inline void
+svc_reserve_auth(struct svc_rqst *rqstp, int space)
+{
+	int			added_space = 0;
+
+	switch(rqstp->rq_authop->flavour) {
+		case RPC_AUTH_GSS:
+			added_space = RPC_MAX_AUTH_SIZE;
+	}
+	return svc_reserve(rqstp, space + added_space);
+}
+
 #endif /* SUNRPC_SVC_H */