hpte_update(mm, addr, old, 0);
hpte_update(mm, addr, ptep, old, 0);
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep){	unsigned long old = pte_update(ptep, ~0UL);	if (old & _PAGE_HASHPTE)		hpte_update(mm, addr, old, 0);	return __pte(old);}