TOPA_ENTRY_PAGES
z_pg = TOPA_ENTRY_PAGES(topa, 0) * (topa->z_count + 1);
idx = (pg - cur_pg) / TOPA_ENTRY_PAGES(topa, 0);
if (cur_pg + TOPA_ENTRY_PAGES(topa, idx) > pg)
cur_pg += TOPA_ENTRY_PAGES(topa, idx);