_PMD_PRESENT
#define pmd_bad(pmd) ((pmd_val(pmd) & _PMD_PRESENT) == 0)
#define pmd_present(pmd) ((pmd_val(pmd) & _PMD_PRESENT) != 0)
*pmdp = __pmd(__pa(pte) | _PMD_PRESENT);
*pmdp = __pmd(__pa(pte_page) | _PMD_PRESENT);
*pmdp = __pmd((unsigned long)pte | _PMD_PRESENT);
*pmdp = __pmd(__pa(pte) | _PMD_PRESENT);
*pmdp = __pmd((unsigned long)pte_page | _PMD_PRESENT);
*pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT);
#define _PMD_PRESENT_MASK _PMD_PRESENT