- while (1) {
- /* End of address space hole, which we mark as non-present. */
- unsigned long hole_end;
-
- if (vma)
- hole_end = min(end, vma->vm_start);
- else
- hole_end = end;
-
- for (; addr < hole_end; addr += PAGE_SIZE) {
- pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
-
- err = add_to_pagemap(addr, &pme, pm);
- if (err)
- return err;
- }
-
- if (!vma || vma->vm_start >= end)
- break;
- /*
- * We can't possibly be in a hugetlb VMA. In general,
- * for a mm_walk with a pmd_entry and a hugetlb_entry,
- * the pmd_entry can only be called on addresses in a
- * hugetlb if the walk starts in a non-hugetlb VMA and
- * spans a hugepage VMA. Since pagemap_read walks are
- * PMD-sized and PMD-aligned, this will never be true.
- */
- BUG_ON(is_vm_hugetlb_page(vma));
-
- /* Addresses in the VMA. */
- orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
- for (; addr < min(end, vma->vm_end); pte++, addr += PAGE_SIZE) {
- pagemap_entry_t pme;
-
- pte_to_pagemap_entry(&pme, pm, vma, addr, *pte);
- err = add_to_pagemap(addr, &pme, pm);
- if (err)
- break;
- }
- pte_unmap_unlock(orig_pte, ptl);
+ /*
+ * We can assume that @vma always points to a valid one and @end never
+ * goes beyond vma->vm_end.
+ */
+ orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
+ for (; addr < end; pte++, addr += PAGE_SIZE) {
+ pagemap_entry_t pme;