CEPH_MSG_CLIENT_SESSION
msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS,
msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h) + extra_bytes,
case CEPH_MSG_CLIENT_SESSION:
case CEPH_MSG_CLIENT_SESSION: return "client_session";