From 3ed3a4f0ddffece942bb2661924d87be4ce63cb7 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Thu, 17 Mar 2016 14:19:11 -0700 Subject: mm: cleanup *pte_alloc* interfaces There are few things about *pte_alloc*() helpers worth cleaning up: - 'vma' argument is unused, let's drop it; - most __pte_alloc() callers do speculative check for pmd_none(), before taking ptl: let's introduce pte_alloc() macro which does the check. The only direct user of __pte_alloc left is userfaultfd, which has different expectation about atomicity wrt pmd. - pte_alloc_map() and pte_alloc_map_lock() are redefined using pte_alloc(). [sudeep.holla@arm.com: fix build for arm64 hugetlbpage] [sfr@canb.auug.org.au: fix arch/arm/mm/mmu.c some more] Signed-off-by: Kirill A. Shutemov Cc: Dave Hansen Signed-off-by: Sudeep Holla Acked-by: Kirill A. Shutemov Signed-off-by: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 8 +++----- mm/mremap.c | 3 +-- mm/userfaultfd.c | 3 +-- 3 files changed, 5 insertions(+), 9 deletions(-) (limited to 'mm') diff --git a/mm/memory.c b/mm/memory.c index 0e247642ed5b..1974fc02c4d0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -562,8 +562,7 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma, } } -int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, - pmd_t *pmd, unsigned long address) +int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address) { spinlock_t *ptl; pgtable_t new = pte_alloc_one(mm, address); @@ -3419,12 +3418,11 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, } /* - * Use __pte_alloc instead of pte_alloc_map, because we can't + * Use pte_alloc() instead of pte_alloc_map, because we can't * run pte_offset_map on the pmd, if an huge pmd could * materialize from under us from a different thread. */ - if (unlikely(pmd_none(*pmd)) && - unlikely(__pte_alloc(mm, vma, pmd, address))) + if (unlikely(pte_alloc(mm, pmd, address))) return VM_FAULT_OOM; /* * If a huge pmd materialized under us just retry later. Use diff --git a/mm/mremap.c b/mm/mremap.c index e30c8a6489a6..3fa0a467df66 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -213,8 +213,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, continue; VM_BUG_ON(pmd_trans_huge(*old_pmd)); } - if (pmd_none(*new_pmd) && __pte_alloc(new_vma->vm_mm, new_vma, - new_pmd, new_addr)) + if (pte_alloc(new_vma->vm_mm, new_pmd, new_addr)) break; next = (new_addr + PMD_SIZE) & PMD_MASK; if (extent > next - new_addr) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 806b0c758c5b..9f3a0290b273 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -230,8 +230,7 @@ retry: break; } if (unlikely(pmd_none(dst_pmdval)) && - unlikely(__pte_alloc(dst_mm, dst_vma, dst_pmd, - dst_addr))) { + unlikely(__pte_alloc(dst_mm, dst_pmd, dst_addr))) { err = -ENOMEM; break; } -- cgit