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 */ 23 int 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 37 int 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 57 int 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 69 int 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 86 pte_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 99 pmd_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 113 void 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 127 void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, 128 pgtable_t pgtable) 129 { 130 assert_spin_locked(&mm->page_table_lock); 131 132 /* FIFO */ 133 if (!mm->pmd_huge_pte) 134 INIT_LIST_HEAD(&pgtable->lru); 135 else 136 list_add(&pgtable->lru, &mm->pmd_huge_pte->lru); 137 mm->pmd_huge_pte = pgtable; 138 } 139 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 140 #endif 141 142 #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW 143 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 144 /* no "address" argument so destroys page coloring of some arch */ 145 pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) 146 { 147 pgtable_t pgtable; 148 149 assert_spin_locked(&mm->page_table_lock); 150 151 /* FIFO */ 152 pgtable = mm->pmd_huge_pte; 153 if (list_empty(&pgtable->lru)) 154 mm->pmd_huge_pte = NULL; 155 else { 156 mm->pmd_huge_pte = list_entry(pgtable->lru.next, 157 struct page, lru); 158 list_del(&pgtable->lru); 159 } 160 return pgtable; 161 } 162 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 163 #endif 164 165 #ifndef __HAVE_ARCH_PMDP_INVALIDATE 166 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 167 void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, 168 pmd_t *pmdp) 169 { 170 set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(*pmdp)); 171 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 172 } 173 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 174 #endif 175