npfkern_m_get
.alloc = npfkern_m_get,
if ((m1 = npfkern_m_get(NULL, M_PKTHDR, tlen)) == NULL) {
#define m_get(x, y) npfkern_m_get(NULL, 0, MLEN)
#define m_gethdr(x, y) npfkern_m_get(NULL, M_PKTHDR, MLEN)
struct mbuf * npfkern_m_get(npf_t *, unsigned, size_t);