From 369ea8242c0fb5239b4ddf0dc568f694bd244de4 Mon Sep 17 00:00:00 2001 From: Jérôme Glisse Date: Thu, 31 Aug 2017 17:17:27 -0400 Subject: mm/rmap: update to new mmu_notifier semantic v2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Replace all mmu_notifier_invalidate_page() calls by *_invalidate_range() and make sure it is bracketed by calls to *_invalidate_range_start()/end(). Note that because we can not presume the pmd value or pte value we have to assume the worst and unconditionaly report an invalidation as happening. Changed since v2: - try_to_unmap_one() only one call to mmu_notifier_invalidate_range() - compute end with PAGE_SIZE << compound_order(page) - fix PageHuge() case in try_to_unmap_one() Signed-off-by: Jérôme Glisse Reviewed-by: Andrea Arcangeli Cc: Dan Williams Cc: Ross Zwisler Cc: Bernhard Held Cc: Adam Borowski Cc: Radim Krčmář Cc: Wanpeng Li Cc: Paolo Bonzini Cc: Takashi Iwai Cc: Nadav Amit Cc: Mike Galbraith Cc: Kirill A. Shutemov Cc: axie Cc: Andrew Morton Signed-off-by: Linus Torvalds --- mm/rmap.c | 35 ++++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) (limited to 'mm/rmap.c') diff --git a/mm/rmap.c b/mm/rmap.c index c8993c63eb25..c570f82e6827 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -887,11 +887,21 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, .address = address, .flags = PVMW_SYNC, }; + unsigned long start = address, end; int *cleaned = arg; + /* + * We have to assume the worse case ie pmd for invalidation. Note that + * the page can not be free from this function. + */ + end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page))); + mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); + while (page_vma_mapped_walk(&pvmw)) { + unsigned long cstart, cend; int ret = 0; - address = pvmw.address; + + cstart = address = pvmw.address; if (pvmw.pte) { pte_t entry; pte_t *pte = pvmw.pte; @@ -904,6 +914,7 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, entry = pte_wrprotect(entry); entry = pte_mkclean(entry); set_pte_at(vma->vm_mm, address, pte, entry); + cend = cstart + PAGE_SIZE; ret = 1; } else { #ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE @@ -918,6 +929,8 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, entry = pmd_wrprotect(entry); entry = pmd_mkclean(entry); set_pmd_at(vma->vm_mm, address, pmd, entry); + cstart &= PMD_MASK; + cend = cstart + PMD_SIZE; ret = 1; #else /* unexpected pmd-mapped page? */ @@ -926,11 +939,13 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, } if (ret) { - mmu_notifier_invalidate_page(vma->vm_mm, address); + mmu_notifier_invalidate_range(vma->vm_mm, cstart, cend); (*cleaned)++; } } + mmu_notifier_invalidate_range_end(vma->vm_mm, start, end); + return true; } @@ -1324,6 +1339,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, pte_t pteval; struct page *subpage; bool ret = true; + unsigned long start = address, end; enum ttu_flags flags = (enum ttu_flags)arg; /* munlock has nothing to gain from examining un-locked vmas */ @@ -1335,6 +1351,14 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, flags & TTU_MIGRATION, page); } + /* + * We have to assume the worse case ie pmd for invalidation. Note that + * the page can not be free in this function as call of try_to_unmap() + * must hold a reference on the page. + */ + end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page))); + mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); + while (page_vma_mapped_walk(&pvmw)) { /* * If the page is mlock()d, we cannot swap it out. @@ -1445,6 +1469,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, if (unlikely(PageSwapBacked(page) != PageSwapCache(page))) { WARN_ON_ONCE(1); ret = false; + /* We have to invalidate as we cleared the pte */ page_vma_mapped_walk_done(&pvmw); break; } @@ -1490,8 +1515,12 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, discard: page_remove_rmap(subpage, PageHuge(page)); put_page(page); - mmu_notifier_invalidate_page(mm, address); + mmu_notifier_invalidate_range(mm, address, + address + PAGE_SIZE); } + + mmu_notifier_invalidate_range_end(vma->vm_mm, start, end); + return ret; } -- cgit v1.2.3