mm: add orig_pte field into vm_fault
Add orig_pte field to vm_fault structure to allow ->page_mkwrite handlers to fully handle the fault. This also allows us to save some passing of extra arguments around. Link: http://lkml.kernel.org/r/1479460644-25076-8-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Родитель
fe82221f57
Коммит
2994302bc8
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@ -298,8 +298,8 @@ struct vm_fault {
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pgoff_t pgoff; /* Logical page offset based on vma */
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unsigned long address; /* Faulting virtual address */
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pmd_t *pmd; /* Pointer to pmd entry matching
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* the 'address'
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*/
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* the 'address' */
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pte_t orig_pte; /* Value of PTE at the time of fault */
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struct page *cow_page; /* Handler may choose to COW */
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struct page *page; /* ->fault handlers should return a
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@ -36,7 +36,7 @@
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/* Do not use these with a slab allocator */
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#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
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int do_swap_page(struct vm_fault *vmf, pte_t orig_pte);
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int do_swap_page(struct vm_fault *vmf);
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void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
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unsigned long floor, unsigned long ceiling);
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@ -875,7 +875,6 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm,
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unsigned long address, pmd_t *pmd,
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int referenced)
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{
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pte_t pteval;
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int swapped_in = 0, ret = 0;
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struct vm_fault vmf = {
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.vma = vma,
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@ -893,11 +892,11 @@ static bool __collapse_huge_page_swapin(struct mm_struct *mm,
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vmf.pte = pte_offset_map(pmd, address);
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for (; vmf.address < address + HPAGE_PMD_NR*PAGE_SIZE;
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vmf.pte++, vmf.address += PAGE_SIZE) {
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pteval = *vmf.pte;
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if (!is_swap_pte(pteval))
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vmf.orig_pte = *vmf.pte;
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if (!is_swap_pte(vmf.orig_pte))
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continue;
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swapped_in++;
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ret = do_swap_page(&vmf, pteval);
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ret = do_swap_page(&vmf);
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/* do_swap_page returns VM_FAULT_RETRY with released mmap_sem */
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if (ret & VM_FAULT_RETRY) {
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82
mm/memory.c
82
mm/memory.c
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@ -2070,8 +2070,8 @@ static int do_page_mkwrite(struct vm_area_struct *vma, struct page *page,
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* case, all we need to do here is to mark the page as writable and update
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* any related book-keeping.
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*/
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static inline int wp_page_reuse(struct vm_fault *vmf, pte_t orig_pte,
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struct page *page, int page_mkwrite, int dirty_shared)
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static inline int wp_page_reuse(struct vm_fault *vmf, struct page *page,
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int page_mkwrite, int dirty_shared)
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__releases(vmf->ptl)
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{
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struct vm_area_struct *vma = vmf->vma;
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@ -2084,8 +2084,8 @@ static inline int wp_page_reuse(struct vm_fault *vmf, pte_t orig_pte,
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if (page)
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page_cpupid_xchg_last(page, (1 << LAST_CPUPID_SHIFT) - 1);
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flush_cache_page(vma, vmf->address, pte_pfn(orig_pte));
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entry = pte_mkyoung(orig_pte);
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flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));
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entry = pte_mkyoung(vmf->orig_pte);
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entry = maybe_mkwrite(pte_mkdirty(entry), vma);
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if (ptep_set_access_flags(vma, vmf->address, vmf->pte, entry, 1))
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update_mmu_cache(vma, vmf->address, vmf->pte);
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@ -2135,8 +2135,7 @@ static inline int wp_page_reuse(struct vm_fault *vmf, pte_t orig_pte,
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* held to the old page, as well as updating the rmap.
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* - In any case, unlock the PTL and drop the reference we took to the old page.
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*/
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static int wp_page_copy(struct vm_fault *vmf, pte_t orig_pte,
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struct page *old_page)
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static int wp_page_copy(struct vm_fault *vmf, struct page *old_page)
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{
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struct vm_area_struct *vma = vmf->vma;
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struct mm_struct *mm = vma->vm_mm;
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@ -2150,7 +2149,7 @@ static int wp_page_copy(struct vm_fault *vmf, pte_t orig_pte,
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if (unlikely(anon_vma_prepare(vma)))
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goto oom;
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if (is_zero_pfn(pte_pfn(orig_pte))) {
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if (is_zero_pfn(pte_pfn(vmf->orig_pte))) {
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new_page = alloc_zeroed_user_highpage_movable(vma,
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vmf->address);
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if (!new_page)
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@ -2174,7 +2173,7 @@ static int wp_page_copy(struct vm_fault *vmf, pte_t orig_pte,
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* Re-check the pte - we dropped the lock
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*/
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vmf->pte = pte_offset_map_lock(mm, vmf->pmd, vmf->address, &vmf->ptl);
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if (likely(pte_same(*vmf->pte, orig_pte))) {
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if (likely(pte_same(*vmf->pte, vmf->orig_pte))) {
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if (old_page) {
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if (!PageAnon(old_page)) {
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dec_mm_counter_fast(mm,
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@ -2184,7 +2183,7 @@ static int wp_page_copy(struct vm_fault *vmf, pte_t orig_pte,
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} else {
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inc_mm_counter_fast(mm, MM_ANONPAGES);
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}
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flush_cache_page(vma, vmf->address, pte_pfn(orig_pte));
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flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));
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entry = mk_pte(new_page, vma->vm_page_prot);
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entry = maybe_mkwrite(pte_mkdirty(entry), vma);
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/*
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@ -2268,7 +2267,7 @@ oom:
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* Handle write page faults for VM_MIXEDMAP or VM_PFNMAP for a VM_SHARED
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* mapping
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*/
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static int wp_pfn_shared(struct vm_fault *vmf, pte_t orig_pte)
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static int wp_pfn_shared(struct vm_fault *vmf)
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{
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struct vm_area_struct *vma = vmf->vma;
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@ -2286,16 +2285,15 @@ static int wp_pfn_shared(struct vm_fault *vmf, pte_t orig_pte)
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* We might have raced with another page fault while we
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* released the pte_offset_map_lock.
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*/
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if (!pte_same(*vmf->pte, orig_pte)) {
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if (!pte_same(*vmf->pte, vmf->orig_pte)) {
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pte_unmap_unlock(vmf->pte, vmf->ptl);
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return 0;
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}
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}
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return wp_page_reuse(vmf, orig_pte, NULL, 0, 0);
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return wp_page_reuse(vmf, NULL, 0, 0);
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}
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static int wp_page_shared(struct vm_fault *vmf, pte_t orig_pte,
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struct page *old_page)
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static int wp_page_shared(struct vm_fault *vmf, struct page *old_page)
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__releases(vmf->ptl)
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{
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struct vm_area_struct *vma = vmf->vma;
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@ -2321,7 +2319,7 @@ static int wp_page_shared(struct vm_fault *vmf, pte_t orig_pte,
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*/
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vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
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vmf->address, &vmf->ptl);
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if (!pte_same(*vmf->pte, orig_pte)) {
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if (!pte_same(*vmf->pte, vmf->orig_pte)) {
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unlock_page(old_page);
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pte_unmap_unlock(vmf->pte, vmf->ptl);
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put_page(old_page);
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@ -2330,7 +2328,7 @@ static int wp_page_shared(struct vm_fault *vmf, pte_t orig_pte,
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page_mkwrite = 1;
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}
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return wp_page_reuse(vmf, orig_pte, old_page, page_mkwrite, 1);
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return wp_page_reuse(vmf, old_page, page_mkwrite, 1);
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}
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/*
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@ -2351,13 +2349,13 @@ static int wp_page_shared(struct vm_fault *vmf, pte_t orig_pte,
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* but allow concurrent faults), with pte both mapped and locked.
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* We return with mmap_sem still held, but pte unmapped and unlocked.
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*/
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static int do_wp_page(struct vm_fault *vmf, pte_t orig_pte)
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static int do_wp_page(struct vm_fault *vmf)
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__releases(vmf->ptl)
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{
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struct vm_area_struct *vma = vmf->vma;
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struct page *old_page;
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old_page = vm_normal_page(vma, vmf->address, orig_pte);
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old_page = vm_normal_page(vma, vmf->address, vmf->orig_pte);
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if (!old_page) {
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/*
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* VM_MIXEDMAP !pfn_valid() case, or VM_SOFTDIRTY clear on a
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@ -2368,10 +2366,10 @@ static int do_wp_page(struct vm_fault *vmf, pte_t orig_pte)
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*/
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if ((vma->vm_flags & (VM_WRITE|VM_SHARED)) ==
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(VM_WRITE|VM_SHARED))
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return wp_pfn_shared(vmf, orig_pte);
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return wp_pfn_shared(vmf);
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pte_unmap_unlock(vmf->pte, vmf->ptl);
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return wp_page_copy(vmf, orig_pte, old_page);
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return wp_page_copy(vmf, old_page);
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}
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/*
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@ -2386,7 +2384,7 @@ static int do_wp_page(struct vm_fault *vmf, pte_t orig_pte)
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lock_page(old_page);
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vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
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vmf->address, &vmf->ptl);
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if (!pte_same(*vmf->pte, orig_pte)) {
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if (!pte_same(*vmf->pte, vmf->orig_pte)) {
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unlock_page(old_page);
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pte_unmap_unlock(vmf->pte, vmf->ptl);
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put_page(old_page);
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@ -2406,12 +2404,12 @@ static int do_wp_page(struct vm_fault *vmf, pte_t orig_pte)
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page_move_anon_rmap(old_page, vma);
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}
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unlock_page(old_page);
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return wp_page_reuse(vmf, orig_pte, old_page, 0, 0);
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return wp_page_reuse(vmf, old_page, 0, 0);
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}
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unlock_page(old_page);
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} else if (unlikely((vma->vm_flags & (VM_WRITE|VM_SHARED)) ==
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(VM_WRITE|VM_SHARED))) {
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return wp_page_shared(vmf, orig_pte, old_page);
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return wp_page_shared(vmf, old_page);
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}
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/*
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@ -2420,7 +2418,7 @@ static int do_wp_page(struct vm_fault *vmf, pte_t orig_pte)
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get_page(old_page);
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pte_unmap_unlock(vmf->pte, vmf->ptl);
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return wp_page_copy(vmf, orig_pte, old_page);
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return wp_page_copy(vmf, old_page);
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}
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static void unmap_mapping_range_vma(struct vm_area_struct *vma,
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@ -2508,7 +2506,7 @@ EXPORT_SYMBOL(unmap_mapping_range);
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* We return with the mmap_sem locked or unlocked in the same cases
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* as does filemap_fault().
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*/
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int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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int do_swap_page(struct vm_fault *vmf)
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{
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struct vm_area_struct *vma = vmf->vma;
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struct page *page, *swapcache;
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@ -2519,10 +2517,10 @@ int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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int exclusive = 0;
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int ret = 0;
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if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, orig_pte))
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if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
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goto out;
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entry = pte_to_swp_entry(orig_pte);
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entry = pte_to_swp_entry(vmf->orig_pte);
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if (unlikely(non_swap_entry(entry))) {
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if (is_migration_entry(entry)) {
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migration_entry_wait(vma->vm_mm, vmf->pmd,
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@ -2530,7 +2528,7 @@ int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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} else if (is_hwpoison_entry(entry)) {
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ret = VM_FAULT_HWPOISON;
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} else {
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print_bad_pte(vma, vmf->address, orig_pte, NULL);
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print_bad_pte(vma, vmf->address, vmf->orig_pte, NULL);
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ret = VM_FAULT_SIGBUS;
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}
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goto out;
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@ -2547,7 +2545,7 @@ int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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*/
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vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
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vmf->address, &vmf->ptl);
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if (likely(pte_same(*vmf->pte, orig_pte)))
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if (likely(pte_same(*vmf->pte, vmf->orig_pte)))
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ret = VM_FAULT_OOM;
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delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
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goto unlock;
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@ -2604,7 +2602,7 @@ int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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*/
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vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address,
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&vmf->ptl);
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if (unlikely(!pte_same(*vmf->pte, orig_pte)))
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if (unlikely(!pte_same(*vmf->pte, vmf->orig_pte)))
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goto out_nomap;
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if (unlikely(!PageUptodate(page))) {
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@ -2632,9 +2630,10 @@ int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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exclusive = RMAP_EXCLUSIVE;
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}
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flush_icache_page(vma, page);
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if (pte_swp_soft_dirty(orig_pte))
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if (pte_swp_soft_dirty(vmf->orig_pte))
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pte = pte_mksoft_dirty(pte);
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set_pte_at(vma->vm_mm, vmf->address, vmf->pte, pte);
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vmf->orig_pte = pte;
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if (page == swapcache) {
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do_page_add_anon_rmap(page, vma, vmf->address, exclusive);
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mem_cgroup_commit_charge(page, memcg, true, false);
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@ -2664,7 +2663,7 @@ int do_swap_page(struct vm_fault *vmf, pte_t orig_pte)
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}
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if (vmf->flags & FAULT_FLAG_WRITE) {
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ret |= do_wp_page(vmf, pte);
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ret |= do_wp_page(vmf);
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if (ret & VM_FAULT_ERROR)
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ret &= VM_FAULT_ERROR;
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goto out;
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@ -3363,7 +3362,7 @@ static int numa_migrate_prep(struct page *page, struct vm_area_struct *vma,
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return mpol_misplaced(page, vma, addr);
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}
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static int do_numa_page(struct vm_fault *vmf, pte_t pte)
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static int do_numa_page(struct vm_fault *vmf)
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{
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struct vm_area_struct *vma = vmf->vma;
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struct page *page = NULL;
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@ -3371,6 +3370,7 @@ static int do_numa_page(struct vm_fault *vmf, pte_t pte)
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int last_cpupid;
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int target_nid;
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bool migrated = false;
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pte_t pte = vmf->orig_pte;
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bool was_writable = pte_write(pte);
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int flags = 0;
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@ -3521,8 +3521,7 @@ static int handle_pte_fault(struct vm_fault *vmf)
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* So now it's safe to run pte_offset_map().
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*/
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vmf->pte = pte_offset_map(vmf->pmd, vmf->address);
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entry = *vmf->pte;
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vmf->orig_pte = *vmf->pte;
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/*
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* some architectures can have larger ptes than wordsize,
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@ -3533,7 +3532,7 @@ static int handle_pte_fault(struct vm_fault *vmf)
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* ptl lock held. So here a barrier will do.
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*/
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barrier();
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if (pte_none(entry)) {
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if (pte_none(vmf->orig_pte)) {
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pte_unmap(vmf->pte);
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vmf->pte = NULL;
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}
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@ -3546,19 +3545,20 @@ static int handle_pte_fault(struct vm_fault *vmf)
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return do_fault(vmf);
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}
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if (!pte_present(entry))
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return do_swap_page(vmf, entry);
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if (!pte_present(vmf->orig_pte))
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return do_swap_page(vmf);
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if (pte_protnone(entry) && vma_is_accessible(vmf->vma))
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return do_numa_page(vmf, entry);
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if (pte_protnone(vmf->orig_pte) && vma_is_accessible(vmf->vma))
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return do_numa_page(vmf);
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vmf->ptl = pte_lockptr(vmf->vma->vm_mm, vmf->pmd);
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spin_lock(vmf->ptl);
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entry = vmf->orig_pte;
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if (unlikely(!pte_same(*vmf->pte, entry)))
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goto unlock;
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if (vmf->flags & FAULT_FLAG_WRITE) {
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if (!pte_write(entry))
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return do_wp_page(vmf, entry);
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return do_wp_page(vmf);
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entry = pte_mkdirty(entry);
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}
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entry = pte_mkyoung(entry);
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