CB_NULL           190 fs/nfs/callback.c 			if (rqstp->rq_proc != CB_NULL)
CB_NULL           462 fs/nfs/callback_xdr.c 	[CB_NULL] = {
CB_NULL           333 fs/nfsd/nfs4callback.c     PROC(CB_NULL,      NULL,     enc_cb_null,     dec_cb_null),