From ec5147dea1b8f02e576a06531d52098045513eda Mon Sep 17 00:00:00 2001 From: Laurent Dufour Date: Tue, 17 Apr 2018 16:33:21 +0200 Subject: [PATCH] mm: introduce __vm_normal_page() When dealing with the speculative fault path we should use the VMA's field cached value stored in the vm_fault structure. Currently vm_normal_page() is using the pointer to the VMA to fetch the vm_flags value. This patch provides a new __vm_normal_page() which is receiving the vm_flags flags value as parameter. Note: The speculative path is turned on for architecture providing support for special PTE flag. So only the first block of vm_normal_page is used during the speculative path. Change-Id: I0f2c4ab1212fbca449bdf6e7993dafa0d41044bc Signed-off-by: Laurent Dufour Patch-mainline: linux-mm @ Tue, 17 Apr 2018 16:33:21 Signed-off-by: Vinayak Menon [charante@codeaurora.org: trivial merge conflict fixes] Signed-off-by: Charan Teja Reddy --- include/linux/mm.h | 10 ++++++++-- mm/memory.c | 24 +++++++++++++++--------- 2 files changed, 23 insertions(+), 11 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index e346d714b454..d05ef12f6f6e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1447,8 +1447,14 @@ struct zap_details { pgoff_t last_index; /* Highest page->index to unmap */ }; -struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, - pte_t pte); +struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr, + pte_t pte, unsigned long vma_flags); +static inline struct page *vm_normal_page(struct vm_area_struct *vma, + unsigned long addr, pte_t pte) +{ + return _vm_normal_page(vma, addr, pte, vma->vm_flags); +} + struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr, pmd_t pmd); diff --git a/mm/memory.c b/mm/memory.c index ed99efeefa11..8136d0f55871 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -553,7 +553,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, } /* - * vm_normal_page -- This function gets the "struct page" associated with a pte. + * __vm_normal_page -- This function gets the "struct page" associated with + * a pte. * * "Special" mappings do not wish to be associated with a "struct page" (either * it doesn't exist, or it exists but they don't want to touch it). In this @@ -594,8 +595,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, * PFNMAP mappings in order to support COWable mappings. * */ -struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, - pte_t pte) +struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr, + pte_t pte, unsigned long vma_flags) { unsigned long pfn = pte_pfn(pte); @@ -604,7 +605,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, goto check_pfn; if (vma->vm_ops && vma->vm_ops->find_special_page) return vma->vm_ops->find_special_page(vma, addr); - if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)) + if (vma_flags & (VM_PFNMAP | VM_MIXEDMAP)) return NULL; if (is_zero_pfn(pfn)) return NULL; @@ -616,9 +617,13 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, } /* !CONFIG_ARCH_HAS_PTE_SPECIAL case follows: */ + /* + * This part should never get called when CONFIG_SPECULATIVE_PAGE_FAULT + * is set. This is mainly because we can't rely on vm_start. + */ - if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) { - if (vma->vm_flags & VM_MIXEDMAP) { + if (unlikely(vma_flags & (VM_PFNMAP|VM_MIXEDMAP))) { + if (vma_flags & VM_MIXEDMAP) { if (!pfn_valid(pfn)) return NULL; goto out; @@ -627,7 +632,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, off = (addr - vma->vm_start) >> PAGE_SHIFT; if (pfn == vma->vm_pgoff + off) return NULL; - if (!is_cow_mapping(vma->vm_flags)) + if (!is_cow_mapping(vma_flags)) return NULL; } } @@ -2619,7 +2624,8 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; - vmf->page = vm_normal_page(vma, vmf->address, vmf->orig_pte); + vmf->page = _vm_normal_page(vma, vmf->address, vmf->orig_pte, + vmf->vma_flags); if (!vmf->page) { /* * VM_MIXEDMAP !pfn_valid() case, or VM_SOFTDIRTY clear on a @@ -3780,7 +3786,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte); update_mmu_cache(vma, vmf->address, vmf->pte); - page = vm_normal_page(vma, vmf->address, pte); + page = _vm_normal_page(vma, vmf->address, pte, vmf->vma_flags); if (!page) { pte_unmap_unlock(vmf->pte, vmf->ptl); return 0;