_bus_dmamap_load_uio
error = _bus_dmamap_load_uio(dmat, map, uio, &nsegs, flags);
error = _bus_dmamap_load_uio(dmat, map, mem->u.md_uio,
error = _bus_dmamap_load_uio(dmat, map, cb->cb_uio, &nsegs,