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/* 14 * If a p?d_bad entry is found while walking page tables, report 15 * the error, before resetting entry to p?d_none. Usually (but 16 * very seldom) called out from the p?d_none_or_clear_bad macros. 17 */ 18 19void pgd_clear_bad(pgd_t *pgd) 20{ 21 pgd_ERROR(*pgd); 22 pgd_clear(pgd); 23} 24 25void pud_clear_bad(pud_t *pud) 26{ 27 pud_ERROR(*pud); 28 pud_clear(pud); 29} 30 31void pmd_clear_bad(pmd_t *pmd) 32{ 33 pmd_ERROR(*pmd); 34 pmd_clear(pmd); 35} 36 37#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 38/* 39 * Only sets the access flags (dirty, accessed), as well as write 40 * permission. Furthermore, we know it always gets set to a "more 41 * permissive" setting, which allows most architectures to optimize 42 * this. We return whether the PTE actually changed, which in turn 43 * instructs the caller to do things like update__mmu_cache. This 44 * used to be done in the caller, but sparc needs minor faults to 45 * force that call on sun4c so we changed this macro slightly 46 */ 47int ptep_set_access_flags(struct vm_area_struct *vma, 48 unsigned long address, pte_t *ptep, 49 pte_t entry, int dirty) 50{ 51 int changed = !pte_same(*ptep, entry); 52 if (changed) { 53 set_pte_at(vma->vm_mm, address, ptep, entry); 54 flush_tlb_fix_spurious_fault(vma, address); 55 } 56 return changed; 57} 58#endif 59 60#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS 61int pmdp_set_access_flags(struct vm_area_struct *vma, 62 unsigned long address, pmd_t *pmdp, 63 pmd_t entry, int dirty) 64{ 65#ifdef CONFIG_TRANSPARENT_HUGEPAGE 66 int changed = !pmd_same(*pmdp, entry); 67 VM_BUG_ON(address & ~HPAGE_PMD_MASK); 68 if (changed) { 69 set_pmd_at(vma->vm_mm, address, pmdp, entry); 70 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 71 } 72 return changed; 73#else /* CONFIG_TRANSPARENT_HUGEPAGE */ 74 BUG(); 75 return 0; 76#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 77} 78#endif 79 80#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH 81int ptep_clear_flush_young(struct vm_area_struct *vma, 82 unsigned long address, pte_t *ptep) 83{ 84 int young; 85 young = ptep_test_and_clear_young(vma, address, ptep); 86 if (young) 87 flush_tlb_page(vma, address); 88 return young; 89} 90#endif 91 92#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH 93int pmdp_clear_flush_young(struct vm_area_struct *vma, 94 unsigned long address, pmd_t *pmdp) 95{ 96 int young; 97#ifdef CONFIG_TRANSPARENT_HUGEPAGE 98 VM_BUG_ON(address & ~HPAGE_PMD_MASK); 99#else 100 BUG(); 101#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 102 young = pmdp_test_and_clear_young(vma, address, pmdp); 103 if (young) 104 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 105 return young; 106} 107#endif 108 109#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH 110pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, 111 pte_t *ptep) 112{ 113 struct mm_struct *mm = (vma)->vm_mm; 114 pte_t pte; 115 pte = ptep_get_and_clear(mm, address, ptep); 116 if (pte_accessible(mm, pte)) 117 flush_tlb_page(vma, address); 118 return pte; 119} 120#endif 121 122#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH 123#ifdef CONFIG_TRANSPARENT_HUGEPAGE 124pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address, 125 pmd_t *pmdp) 126{ 127 pmd_t pmd; 128 VM_BUG_ON(address & ~HPAGE_PMD_MASK); 129 pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp); 130 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 131 return pmd; 132} 133#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 134#endif 135 136#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH 137#ifdef CONFIG_TRANSPARENT_HUGEPAGE 138void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, 139 pmd_t *pmdp) 140{ 141 pmd_t pmd = pmd_mksplitting(*pmdp); 142 VM_BUG_ON(address & ~HPAGE_PMD_MASK); 143 set_pmd_at(vma->vm_mm, address, pmdp, pmd); 144 /* tlb flush only to serialize against gup-fast */ 145 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 146} 147#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 148#endif 149 150#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT 151#ifdef CONFIG_TRANSPARENT_HUGEPAGE 152void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, 153 pgtable_t pgtable) 154{ 155 assert_spin_locked(pmd_lockptr(mm, pmdp)); 156 157 /* FIFO */ 158 if (!pmd_huge_pte(mm, pmdp)) 159 INIT_LIST_HEAD(&pgtable->lru); 160 else 161 list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru); 162 pmd_huge_pte(mm, pmdp) = pgtable; 163} 164#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 165#endif 166 167#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW 168#ifdef CONFIG_TRANSPARENT_HUGEPAGE 169/* no "address" argument so destroys page coloring of some arch */ 170pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) 171{ 172 pgtable_t pgtable; 173 174 assert_spin_locked(pmd_lockptr(mm, pmdp)); 175 176 /* FIFO */ 177 pgtable = pmd_huge_pte(mm, pmdp); 178 if (list_empty(&pgtable->lru)) 179 pmd_huge_pte(mm, pmdp) = NULL; 180 else { 181 pmd_huge_pte(mm, pmdp) = list_entry(pgtable->lru.next, 182 struct page, lru); 183 list_del(&pgtable->lru); 184 } 185 return pgtable; 186} 187#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 188#endif 189 190#ifndef __HAVE_ARCH_PMDP_INVALIDATE 191#ifdef CONFIG_TRANSPARENT_HUGEPAGE 192void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, 193 pmd_t *pmdp) 194{ 195 pmd_t entry = *pmdp; 196 set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(entry)); 197 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 198} 199#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 200#endif 201