wb_data
f->wb_data = vtophys(mtod(m, vm_offset_t));
f->wb_data = vtophys(mtod(m_new, caddr_t));
f->wb_data = vtophys(&sc->wb_cdata.wb_pad);
c->wb_ptr->wb_data = vtophys(mtod(m_new, caddr_t));
#define WB_TXDATA(x) x->wb_ptr->wb_frag[x->wb_lastdesc].wb_data
uint32_t wb_data[1024];