emac_control_data
#define EMAC_CDOFF(x) offsetof(struct emac_control_data, x)
struct emac_control_data *sc_control_data;
sizeof(struct emac_control_data), 0, 0, &seg, 1, &nseg, 0)) != 0) {
sizeof(struct emac_control_data), (void **)&sc->sc_control_data,
sizeof(struct emac_control_data), 1,
sizeof(struct emac_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
sc->sc_control_data, sizeof(struct emac_control_data), NULL,
sizeof(struct emac_control_data));