RPCSVC_MAXPAYLOAD
NFSSVC_MAXBLKSIZE = RPCSVC_MAXPAYLOAD,
RPCSVC_MAXPAYLOAD_TCP = RPCSVC_MAXPAYLOAD,
#define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD
if (bufsize > RPCSVC_MAXPAYLOAD)
bufsize = RPCSVC_MAXPAYLOAD;