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    Subject[PATCH v2 12/20] mm: Introduce __vm_normal_page()
    Date
    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.

    Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
    ---
    mm/memory.c | 25 +++++++++++++++++--------
    1 file changed, 17 insertions(+), 8 deletions(-)

    diff --git a/mm/memory.c b/mm/memory.c
    index ad7b6372d302..9f9e5bb7a556 100644
    --- a/mm/memory.c
    +++ b/mm/memory.c
    @@ -820,8 +820,9 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
    #else
    # define HAVE_PTE_SPECIAL 0
    #endif
    -struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
    - pte_t pte)
    +static 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);

    @@ -830,7 +831,7 @@ 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))
    print_bad_pte(vma, addr, pte, NULL);
    @@ -839,8 +840,8 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,

    /* !HAVE_PTE_SPECIAL case follows: */

    - 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;
    @@ -849,7 +850,7 @@ 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;
    }
    }
    @@ -870,6 +871,13 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
    return pfn_to_page(pfn);
    }

    +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);
    +}
    +
    +
    #ifdef CONFIG_TRANSPARENT_HUGEPAGE
    struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
    pmd_t pmd)
    @@ -2548,7 +2556,8 @@ static int 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
    @@ -3575,7 +3584,7 @@ static int do_numa_page(struct vm_fault *vmf)
    ptep_modify_prot_commit(vma->vm_mm, vmf->address, vmf->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;
    --
    2.7.4
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