dc_data
sframe->dc_data = vtophys(&sc->dc_cdata.dc_sbuf);
sframe->dc_data = vtophys(&sc->dc_cdata.dc_sbuf);
ld->dc_tx_list[i].dc_data = 0;
c->dc_data = vtophys(mtod(m_new, caddr_t));
f->dc_data = vtophys(mtod(m, vm_offset_t));