diskstrategy
{ "disk", diskstrategy, diskopen, diskclose, diskioctl }, /*0*/
i = diskstrategy(sc, F_READ,
int diskstrategy(void *, int, daddr_t, size_t, void *, size_t *);
diskstrategy, diskopen, diskclose, diskioctl }
i = diskstrategy(sc, F_READ, LABELSECTOR, DEV_BSIZE, buf, &cnt);
int diskstrategy(void *, int, daddr_t, size_t, void *, size_t *);