xyc_startbuf
xyc_startbuf(xycsc, xy, bufq_peek(xy->xyq));
int xyc_startbuf(struct xyc_softc *, struct xy_softc *, struct buf *);
int xyc_startbuf(struct xyc_softc *, struct xy_softc *, struct buf *);
xyc_startbuf(xycsc, xy, bufq_peek(xy->xyq));