From 8cff39564987b5b591128997d9035a5f89bdbff4 Mon Sep 17 00:00:00 2001 From: Rolf Eike Beer Date: Mon, 22 Aug 2022 15:04:12 +0200 Subject: [PATCH] mm: pagewalk: move variables to more local scope, tweak loops Move some variables to more local scopes to make it obvious that they don't carry state. Put the end additions into the for loop instructions to make them easier to read. Link: https://lkml.kernel.org/r/8155217.NyiUUSuA9g@devpool047 Signed-off-by: Rolf Eike Beer Signed-off-by: Andrew Morton --- mm/pagewalk.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/mm/pagewalk.c b/mm/pagewalk.c index 7629838eea13..54b2a1beeeb3 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -25,14 +25,12 @@ static int walk_pte_range_inner(pte_t *pte, unsigned long addr, { const struct mm_walk_ops *ops = walk->ops; - for (;;) { + for (;; addr += PAGE_SIZE, pte++) { int err = ops->pte_entry(pte, addr, addr + PAGE_SIZE, walk); if (err) return err; if (addr >= end - PAGE_SIZE) break; - addr += PAGE_SIZE; - pte++; } return 0; } @@ -42,13 +40,14 @@ static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, { pte_t *pte; int err; - spinlock_t *ptl; if (walk->no_vma) { pte = pte_offset_map(pmd, addr); err = walk_pte_range_inner(pte, addr, end, walk); pte_unmap(pte); } else { + spinlock_t *ptl; + pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); err = walk_pte_range_inner(pte, addr, end, walk); pte_unmap_unlock(pte, ptl); @@ -71,7 +70,7 @@ static int walk_hugepd_range(hugepd_t *phpd, unsigned long addr, if (addr & (page_size - 1)) return 0; - for (;;) { + for (;; addr += page_size) { pte_t *pte; int err; @@ -84,7 +83,6 @@ static int walk_hugepd_range(hugepd_t *phpd, unsigned long addr, return err; if (addr >= end - page_size) break; - addr += page_size; } return 0; } @@ -307,14 +305,13 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end, unsigned long next; unsigned long hmask = huge_page_mask(h); unsigned long sz = huge_page_size(h); - pte_t *pte; const struct mm_walk_ops *ops = walk->ops; - do { + for (; addr < end; addr = next) { int err; + pte_t *pte = huge_pte_offset(walk->mm, addr & hmask, sz); next = hugetlb_entry_end(h, addr, end); - pte = huge_pte_offset(walk->mm, addr & hmask, sz); if (pte) err = ops->hugetlb_entry(pte, hmask, addr, next, walk); @@ -323,7 +320,7 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end, if (err) return err; - } while (addr = next, addr != end); + } return 0; } @@ -461,14 +458,13 @@ int walk_page_range(struct mm_struct *mm, unsigned long start, do { int err; + walk.vma = vma; if (!vma) { /* after the last vma */ - walk.vma = NULL; next = end; } else if (start < vma->vm_start) { /* outside vma */ walk.vma = NULL; next = min(end, vma->vm_start); } else { /* inside vma */ - walk.vma = vma; next = min(end, vma->vm_end); vma = find_vma(mm, vma->vm_end); @@ -595,11 +591,11 @@ int walk_page_mapping(struct address_space *mapping, pgoff_t first_index, }; struct vm_area_struct *vma; pgoff_t vba, vea, cba, cea; - unsigned long start_addr, end_addr; lockdep_assert_held(&mapping->i_mmap_rwsem); vma_interval_tree_foreach(vma, &mapping->i_mmap, first_index, first_index + nr - 1) { + unsigned long start_addr, end_addr; int err; /* Clip to the vma */ -- 2.50.1