LXR linux/mm/pgtable-generic.c

   1/*
   2 *  mm/pgtable-generic.c
   3 *
   4 *  Generic pgtable methods declared in asm-generic/pgtable.h
   5 *
   6 *  Copyright (C) 2010  Linus Torvalds
   7 */
   8
   9#include <linux/pagemap.h>
  10#include <asm/tlb.h>
  11#include <asm-generic/pgtable.h>
  12
  13#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
  14/*
  15 * Only sets the access flags (dirty, accessed), as well as write 
  16 * permission. Furthermore, we know it always gets set to a "more
  17 * permissive" setting, which allows most architectures to optimize
  18 * this. We return whether the PTE actually changed, which in turn
  19 * instructs the caller to do things like update__mmu_cache.  This
  20 * used to be done in the caller, but sparc needs minor faults to
  21 * force that call on sun4c so we changed this macro slightly
  22 */
  23int ptep_set_access_flags(struct vm_area_struct *vma,
  24                          unsigned long address, pte_t *ptep,
  25                          pte_t entry, int dirty)
  26{
  27        int changed = !pte_same(*ptep, entry);
  28        if (changed) {
  29                set_pte_at(vma->vm_mm, address, ptep, entry);
  30                flush_tlb_fix_spurious_fault(vma, address);
  31        }
  32        return changed;
  33}
  34#endif
  35
  36#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
  37int pmdp_set_access_flags(struct vm_area_struct *vma,
  38                          unsigned long address, pmd_t *pmdp,
  39                          pmd_t entry, int dirty)
  40{
  41#ifdef CONFIG_TRANSPARENT_HUGEPAGE
  42        int changed = !pmd_same(*pmdp, entry);
  43        VM_BUG_ON(address & ~HPAGE_PMD_MASK);
  44        if (changed) {
  45                set_pmd_at(vma->vm_mm, address, pmdp, entry);
  46                flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
  47        }
  48        return changed;
  49#else /* CONFIG_TRANSPARENT_HUGEPAGE */
  50        BUG();
  51        return 0;
  52#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  53}
  54#endif
  55
  56#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
  57int ptep_clear_flush_young(struct vm_area_struct *vma,
  58                           unsigned long address, pte_t *ptep)
  59{
  60        int young;
  61        young = ptep_test_and_clear_young(vma, address, ptep);
  62        if (young)
  63                flush_tlb_page(vma, address);
  64        return young;
  65}
  66#endif
  67
  68#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
  69int pmdp_clear_flush_young(struct vm_area_struct *vma,
  70                           unsigned long address, pmd_t *pmdp)
  71{
  72        int young;
  73#ifdef CONFIG_TRANSPARENT_HUGEPAGE
  74        VM_BUG_ON(address & ~HPAGE_PMD_MASK);
  75#else
  76        BUG();
  77#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  78        young = pmdp_test_and_clear_young(vma, address, pmdp);
  79        if (young)
  80                flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
  81        return young;
  82}
  83#endif
  84
  85#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
  86pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
  87                       pte_t *ptep)
  88{
  89        pte_t pte;
  90        pte = ptep_get_and_clear((vma)->vm_mm, address, ptep);
  91        if (pte_accessible(pte))
  92                flush_tlb_page(vma, address);
  93        return pte;
  94}
  95#endif
  96
  97#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
  98#ifdef CONFIG_TRANSPARENT_HUGEPAGE
  99pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
 100                       pmd_t *pmdp)
 101{
 102        pmd_t pmd;
 103        VM_BUG_ON(address & ~HPAGE_PMD_MASK);
 104        pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
 105        flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 106        return pmd;
 107}
 108#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 109#endif
 110
 111#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
 112#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 113void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
 114                          pmd_t *pmdp)
 115{
 116        pmd_t pmd = pmd_mksplitting(*pmdp);
 117        VM_BUG_ON(address & ~HPAGE_PMD_MASK);
 118        set_pmd_at(vma->vm_mm, address, pmdp, pmd);
 119        /* tlb flush only to serialize against gup-fast */
 120        flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 121}
 122#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 123#endif
 124
 125#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
 126#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 127void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable)
 128{
 129        assert_spin_locked(&mm->page_table_lock);
 130
 131        /* FIFO */
 132        if (!mm->pmd_huge_pte)
 133                INIT_LIST_HEAD(&pgtable->lru);
 134        else
 135                list_add(&pgtable->lru, &mm->pmd_huge_pte->lru);
 136        mm->pmd_huge_pte = pgtable;
 137}
 138#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 139#endif
 140
 141#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW
 142#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 143/* no "address" argument so destroys page coloring of some arch */
 144pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm)
 145{
 146        pgtable_t pgtable;
 147
 148        assert_spin_locked(&mm->page_table_lock);
 149
 150        /* FIFO */
 151        pgtable = mm->pmd_huge_pte;
 152        if (list_empty(&pgtable->lru))
 153                mm->pmd_huge_pte = NULL;
 154        else {
 155                mm->pmd_huge_pte = list_entry(pgtable->lru.next,
 156                                              struct page, lru);
 157                list_del(&pgtable->lru);
 158        }
 159        return pgtable;
 160}
 161#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 162#endif
 163
 164#ifndef __HAVE_ARCH_PMDP_INVALIDATE
 165#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 166void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
 167                     pmd_t *pmdp)
 168{
 169        set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(*pmdp));
 170        flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 171}
 172#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 173#endif
 174