MBUF_LEN
nm_prinf("sending up pkt %p size %d", m, MBUF_LEN(m));
int len = MBUF_LEN(m);
u_int len = MBUF_LEN(m);
if (unlikely(!gna->rxsg && MBUF_LEN(m) > NETMAP_BUF_SIZE(na))) {
"(size=%d)", (int)MBUF_LEN(m));
mlen = MBUF_LEN(m);