pmd_hugepage_update
old = pmd_hugepage_update(mm, addr, pmdp, _PAGE_ACCESSED, 0);
pmd_hugepage_update(mm, addr, pmdp, _PAGE_WRITE, 0);
old = pmd_hugepage_update(mm, addr, pmdp, ~0UL, 0);
old_pmd = __pmd(pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID));