DN_USED_BYTES
doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9;
*nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
DN_USED_BYTES(dn->dn_phys), dn->dn_phys->dn_flags,
space = DN_USED_BYTES(dn->dn_phys);
ASSERT3U(bytesfreed, <=, DN_USED_BYTES(dn->dn_phys));
ASSERT0(DN_USED_BYTES(dn->dn_phys));
dn->dn_oldused = DN_USED_BYTES(dn->dn_phys);