cbtorpos
cg_blks(fs, newcg, j)[cbtorpos(fs, i)]++;
rpos = cbtorpos(&sblock, i);
[cbtorpos(&sblock, d)]++;
[cbtorpos(&sblock, d)]++;
cg_blks(&sblock, &acg, cbtocylno(&sblock, d))[cbtorpos(&sblock, d)]--;
cg_blks(&sblock, &acg, cno)[cbtorpos(&sblock, bit)]++;
pos = cbtorpos(ufsvfsp, bpref);
rpos = cbtorpos(ufsvfsp, bno);
rpos = cbtorpos(ufsvfsp, bno);
rpos = cbtorpos(ufsvfsp, bbase);