pgd_t *pgd;
pud_t *pud;
static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr){	pgd_t *pgd;	BUG_ON(! in_hugepage_area(mm->context, addr));	pgd = hugepgd_alloc(mm, addr);	if (! pgd)		return NULL;	return hugepte_alloc(mm, pgd, addr);}