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, and 16 * writable). 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_page(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 flush_tlb_page(vma, address); 92 return pte; 93 } 94 #endif 95 96 #ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH 97 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 98 pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address, 99 pmd_t *pmdp) 100 { 101 pmd_t pmd; 102 VM_BUG_ON(address & ~HPAGE_PMD_MASK); 103 pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp); 104 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 105 return pmd; 106 } 107 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 108 #endif 109 110 #ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH 111 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 112 pmd_t pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, 113 pmd_t *pmdp) 114 { 115 pmd_t pmd = pmd_mksplitting(*pmdp); 116 VM_BUG_ON(address & ~HPAGE_PMD_MASK); 117 set_pmd_at(vma->vm_mm, address, pmdp, pmd); 118 /* tlb flush only to serialize against gup-fast */ 119 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); 120 } 121 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 122 #endif 123