viogpu_cmd_sync
viogpu_cmd_sync(sc, &hdr, sizeof(hdr), &info, sizeof(info));
viogpu_cmd_sync(sc, &res, sizeof(res), &resp, sizeof(resp));
viogpu_cmd_sync(sc, &ss, sizeof(ss), &resp, sizeof(resp));
viogpu_cmd_sync(sc, &backing, sizeof(backing), &resp, sizeof(resp));
static int viogpu_cmd_sync(struct viogpu_softc *, void *, size_t, void *,