GET_BP_SEC
pktp->cp_srtsec = GET_BP_SEC(bp);
SET_BP_SEC(bp, (LBLK2SEC(GET_BP_SEC(bp), dadkp->dad_blkshf)));
SET_BP_SEC(bp, (LBLK2SEC(GET_BP_SEC(bp), dadkp->dad_blkshf)));
i = cmdk_bbh_bsearch(altp, alts_used, GET_BP_SEC(bp));
lastsec = GET_BP_SEC(bp) + d_count - 1;
ckp[0].ck_sector = GET_BP_SEC(bp);