gdt_ccb_set_cmd
gdt_ccb_set_cmd(ccb, GDT_GCF_INTERNAL);
(void)gdt_ccb_set_cmd(sc->sc_ccbs + i, GDT_GCF_UNUSED);
gdt_ccb_set_cmd(ccb, GDT_GCF_SCSI);
static inline int gdt_ccb_set_cmd(struct gdt_ccb *, int);