pagewalk: don't look up vma if walk->hugetlb_entry is unused

	return 0;

}

#endif

static struct vm_area_struct* hugetlb_vma(unsigned long addr, struct mm_walk *walk)

{

	struct vm_area_struct *vma;

	/* We don't need vma lookup at all. */

	if (!walk->hugetlb_entry)

		return NULL;

	VM_BUG_ON(!rwsem_is_locked(&walk->mm->mmap_sem));

	vma = find_vma(walk->mm, addr);

	if (vma && vma->vm_start <= addr && is_vm_hugetlb_page(vma))

		return vma;

	return NULL;

}

#else /* CONFIG_HUGETLB_PAGE */

static struct vm_area_struct* hugetlb_vma(unsigned long addr, struct mm_walk *walk)

{

	return NULL;

}

static int walk_hugetlb_range(struct vm_area_struct *vma,

			      unsigned long addr, unsigned long end,

			      struct mm_walk *walk)

{

	return 0;

}

#endif /* CONFIG_HUGETLB_PAGE */

/**

 * walk_page_range - walk a memory map's page tables with a callback

	pgd = pgd_offset(walk->mm, addr);

	do {

		struct vm_area_struct *uninitialized_var(vma);

		struct vm_area_struct *vma;

		next = pgd_addr_end(addr, end);

#ifdef CONFIG_HUGETLB_PAGE

		/*

		 * handle hugetlb vma individually because pagetable walk for

		 * the hugetlb page is dependent on the architecture and

		 * we can't handled it in the same manner as non-huge pages.

		 */

		vma = find_vma(walk->mm, addr);

		if (vma && vma->vm_start <= addr && is_vm_hugetlb_page(vma)) {

		vma = hugetlb_vma(addr, walk);

		if (vma) {

			if (vma->vm_end < next)

				next = vma->vm_end;

			/*

			pgd = pgd_offset(walk->mm, next);

			continue;

		}

#endif

		if (pgd_none_or_clear_bad(pgd)) {

			if (walk->pte_hole)

				err = walk->pte_hole(addr, next, walk);