Linux kernel mirror (for testing)
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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