RDS: Implement silent atomics

Signed-off-by: Andy Grover <andy.grover@oracle.com>

net/rds/message.c

@@ -325,6 +325,8 @@ int rds_message_copy_from_user(struct rds_message *rm, struct iovec *first_iov,
 			sg++;
 	}
 
+	rm->data.op_active = 1;
+
 out:
 	return ret;
 }