DH_NBLKOFF
#define DH_BLKOFFMASK (DH_NBLKOFF - 1)
ufsdirhash_zone = uma_zcreate("DIRHASH", DH_NBLKOFF * sizeof(doff_t),
narrays = howmany(nslots, DH_NBLKOFF);
nslots = narrays * DH_NBLKOFF;
narrays * DH_NBLKOFF * sizeof(**dh->dh_hash) +
for (j = 0; j < DH_NBLKOFF; j++)