From 7868a2087ec13ec4a5df0c5e00999863be132ba8 Mon Sep 17 00:00:00 2001 From: Punit Agrawal Date: Thu, 6 Jul 2017 15:39:42 -0700 Subject: mm/hugetlb: add size parameter to huge_pte_offset() A poisoned or migrated hugepage is stored as a swap entry in the page tables. On architectures that support hugepages consisting of contiguous page table entries (such as on arm64) this leads to ambiguity in determining the page table entry to return in huge_pte_offset() when a poisoned entry is encountered. Let's remove the ambiguity by adding a size parameter to convey additional information about the requested address. Also fixup the definition/usage of huge_pte_offset() throughout the tree. Link: http://lkml.kernel.org/r/20170522133604.11392-4-punit.agrawal@arm.com Signed-off-by: Punit Agrawal Acked-by: Steve Capper Cc: Catalin Marinas Cc: Will Deacon Cc: Tony Luck Cc: Fenghua Yu Cc: James Hogan (odd fixer:METAG ARCHITECTURE) Cc: Ralf Baechle (supporter:MIPS) Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Yoshinori Sato Cc: Rich Felker Cc: "David S. Miller" Cc: Chris Metcalf Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Alexander Viro Cc: Michal Hocko Cc: Mike Kravetz Cc: Naoya Horiguchi Cc: "Aneesh Kumar K.V" Cc: "Kirill A. Shutemov" Cc: Hillf Danton Cc: Mark Rutland Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index c73828e43100..075345532396 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3246,7 +3246,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { spinlock_t *src_ptl, *dst_ptl; - src_pte = huge_pte_offset(src, addr); + src_pte = huge_pte_offset(src, addr, sz); if (!src_pte) continue; dst_pte = huge_pte_alloc(dst, addr, sz); @@ -3330,7 +3330,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); address = start; for (; address < end; address += sz) { - ptep = huge_pte_offset(mm, address); + ptep = huge_pte_offset(mm, address, sz); if (!ptep) continue; @@ -3548,7 +3548,8 @@ retry_avoidcopy: unmap_ref_private(mm, vma, old_page, address); BUG_ON(huge_pte_none(pte)); spin_lock(ptl); - ptep = huge_pte_offset(mm, address & huge_page_mask(h)); + ptep = huge_pte_offset(mm, address & huge_page_mask(h), + huge_page_size(h)); if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) goto retry_avoidcopy; @@ -3587,7 +3588,8 @@ retry_avoidcopy: * before the page tables are altered */ spin_lock(ptl); - ptep = huge_pte_offset(mm, address & huge_page_mask(h)); + ptep = huge_pte_offset(mm, address & huge_page_mask(h), + huge_page_size(h)); if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { ClearPagePrivate(new_page); @@ -3874,7 +3876,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, address &= huge_page_mask(h); - ptep = huge_pte_offset(mm, address); + ptep = huge_pte_offset(mm, address, huge_page_size(h)); if (ptep) { entry = huge_ptep_get(ptep); if (unlikely(is_hugetlb_entry_migration(entry))) { @@ -4131,7 +4133,8 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, * * Note that page table lock is not held when pte is null. */ - pte = huge_pte_offset(mm, vaddr & huge_page_mask(h)); + pte = huge_pte_offset(mm, vaddr & huge_page_mask(h), + huge_page_size(h)); if (pte) ptl = huge_pte_lock(h, mm, pte); absent = !pte || huge_pte_none(huge_ptep_get(pte)); @@ -4270,7 +4273,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, i_mmap_lock_write(vma->vm_file->f_mapping); for (; address < end; address += huge_page_size(h)) { spinlock_t *ptl; - ptep = huge_pte_offset(mm, address); + ptep = huge_pte_offset(mm, address, huge_page_size(h)); if (!ptep) continue; ptl = huge_pte_lock(h, mm, ptep); @@ -4534,7 +4537,8 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) saddr = page_table_shareable(svma, vma, addr, idx); if (saddr) { - spte = huge_pte_offset(svma->vm_mm, saddr); + spte = huge_pte_offset(svma->vm_mm, saddr, + vma_mmu_pagesize(svma)); if (spte) { get_page(virt_to_page(spte)); break; @@ -4630,7 +4634,8 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, return pte; } -pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) +pte_t *huge_pte_offset(struct mm_struct *mm, + unsigned long addr, unsigned long sz) { pgd_t *pgd; p4d_t *p4d; -- cgit v1.2.1