l2cap_hdr_t
if (m->m_pkthdr.len < sizeof(l2cap_hdr_t)) {
want = letoh16(want) + sizeof(l2cap_hdr_t) - got;
l2cap_hdr_t hdr;
l2cap_hdr_t *hdr;
hdr = mtod(m, l2cap_hdr_t *);
l2cap_hdr_t *hdr;
M_PREPEND(m, sizeof(l2cap_hdr_t), M_NOWAIT);
hdr = mtod(m, l2cap_hdr_t *);