find_pmd_or_thp_or_none
result = find_pmd_or_thp_or_none(mm, address, &pmd);
result = find_pmd_or_thp_or_none(mm, start_addr, &pmd);
result = find_pmd_or_thp_or_none(mm, haddr, &pmd);
result = find_pmd_or_thp_or_none(mm, haddr, &pmd);
if (find_pmd_or_thp_or_none(mm, addr, &pmd) != SCAN_SUCCEED)
enum scan_result result = find_pmd_or_thp_or_none(mm, address, &new_pmd);