Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * mm/pgtable-generic.c
4 : *
5 : * Generic pgtable methods declared in linux/pgtable.h
6 : *
7 : * Copyright (C) 2010 Linus Torvalds
8 : */
9 :
10 : #include <linux/pagemap.h>
11 : #include <linux/hugetlb.h>
12 : #include <linux/pgtable.h>
13 : #include <linux/mm_inline.h>
14 : #include <asm/tlb.h>
15 :
16 : /*
17 : * If a p?d_bad entry is found while walking page tables, report
18 : * the error, before resetting entry to p?d_none. Usually (but
19 : * very seldom) called out from the p?d_none_or_clear_bad macros.
20 : */
21 :
22 0 : void pgd_clear_bad(pgd_t *pgd)
23 : {
24 0 : pgd_ERROR(*pgd);
25 0 : pgd_clear(pgd);
26 0 : }
27 :
28 : #ifndef __PAGETABLE_P4D_FOLDED
29 : void p4d_clear_bad(p4d_t *p4d)
30 : {
31 : p4d_ERROR(*p4d);
32 : p4d_clear(p4d);
33 : }
34 : #endif
35 :
36 : #ifndef __PAGETABLE_PUD_FOLDED
37 : void pud_clear_bad(pud_t *pud)
38 : {
39 : pud_ERROR(*pud);
40 : pud_clear(pud);
41 : }
42 : #endif
43 :
44 : /*
45 : * Note that the pmd variant below can't be stub'ed out just as for p4d/pud
46 : * above. pmd folding is special and typically pmd_* macros refer to upper
47 : * level even when folded
48 : */
49 0 : void pmd_clear_bad(pmd_t *pmd)
50 : {
51 0 : pmd_ERROR(*pmd);
52 0 : pmd_clear(pmd);
53 0 : }
54 :
55 : #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
56 : /*
57 : * Only sets the access flags (dirty, accessed), as well as write
58 : * permission. Furthermore, we know it always gets set to a "more
59 : * permissive" setting, which allows most architectures to optimize
60 : * this. We return whether the PTE actually changed, which in turn
61 : * instructs the caller to do things like update__mmu_cache. This
62 : * used to be done in the caller, but sparc needs minor faults to
63 : * force that call on sun4c so we changed this macro slightly
64 : */
65 0 : int ptep_set_access_flags(struct vm_area_struct *vma,
66 : unsigned long address, pte_t *ptep,
67 : pte_t entry, int dirty)
68 : {
69 0 : int changed = !pte_same(*ptep, entry);
70 0 : if (changed) {
71 0 : set_pte_at(vma->vm_mm, address, ptep, entry);
72 0 : flush_tlb_fix_spurious_fault(vma, address);
73 : }
74 0 : return changed;
75 : }
76 : #endif
77 :
78 : #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
79 0 : int ptep_clear_flush_young(struct vm_area_struct *vma,
80 : unsigned long address, pte_t *ptep)
81 : {
82 : int young;
83 0 : young = ptep_test_and_clear_young(vma, address, ptep);
84 0 : if (young)
85 0 : flush_tlb_page(vma, address);
86 0 : return young;
87 : }
88 : #endif
89 :
90 : #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
91 0 : pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
92 : pte_t *ptep)
93 : {
94 0 : struct mm_struct *mm = (vma)->vm_mm;
95 : pte_t pte;
96 0 : pte = ptep_get_and_clear(mm, address, ptep);
97 : if (pte_accessible(mm, pte))
98 0 : flush_tlb_page(vma, address);
99 0 : return pte;
100 : }
101 : #endif
102 :
103 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
104 :
105 : #ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
106 : int pmdp_set_access_flags(struct vm_area_struct *vma,
107 : unsigned long address, pmd_t *pmdp,
108 : pmd_t entry, int dirty)
109 : {
110 : int changed = !pmd_same(*pmdp, entry);
111 : VM_BUG_ON(address & ~HPAGE_PMD_MASK);
112 : if (changed) {
113 : set_pmd_at(vma->vm_mm, address, pmdp, entry);
114 : flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
115 : }
116 : return changed;
117 : }
118 : #endif
119 :
120 : #ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
121 : int pmdp_clear_flush_young(struct vm_area_struct *vma,
122 : unsigned long address, pmd_t *pmdp)
123 : {
124 : int young;
125 : VM_BUG_ON(address & ~HPAGE_PMD_MASK);
126 : young = pmdp_test_and_clear_young(vma, address, pmdp);
127 : if (young)
128 : flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
129 : return young;
130 : }
131 : #endif
132 :
133 : #ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH
134 : pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address,
135 : pmd_t *pmdp)
136 : {
137 : pmd_t pmd;
138 : VM_BUG_ON(address & ~HPAGE_PMD_MASK);
139 : VM_BUG_ON(pmd_present(*pmdp) && !pmd_trans_huge(*pmdp) &&
140 : !pmd_devmap(*pmdp));
141 : pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
142 : flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
143 : return pmd;
144 : }
145 :
146 : #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
147 : pud_t pudp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address,
148 : pud_t *pudp)
149 : {
150 : pud_t pud;
151 :
152 : VM_BUG_ON(address & ~HPAGE_PUD_MASK);
153 : VM_BUG_ON(!pud_trans_huge(*pudp) && !pud_devmap(*pudp));
154 : pud = pudp_huge_get_and_clear(vma->vm_mm, address, pudp);
155 : flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE);
156 : return pud;
157 : }
158 : #endif
159 : #endif
160 :
161 : #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
162 : void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
163 : pgtable_t pgtable)
164 : {
165 : assert_spin_locked(pmd_lockptr(mm, pmdp));
166 :
167 : /* FIFO */
168 : if (!pmd_huge_pte(mm, pmdp))
169 : INIT_LIST_HEAD(&pgtable->lru);
170 : else
171 : list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru);
172 : pmd_huge_pte(mm, pmdp) = pgtable;
173 : }
174 : #endif
175 :
176 : #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW
177 : /* no "address" argument so destroys page coloring of some arch */
178 : pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
179 : {
180 : pgtable_t pgtable;
181 :
182 : assert_spin_locked(pmd_lockptr(mm, pmdp));
183 :
184 : /* FIFO */
185 : pgtable = pmd_huge_pte(mm, pmdp);
186 : pmd_huge_pte(mm, pmdp) = list_first_entry_or_null(&pgtable->lru,
187 : struct page, lru);
188 : if (pmd_huge_pte(mm, pmdp))
189 : list_del(&pgtable->lru);
190 : return pgtable;
191 : }
192 : #endif
193 :
194 : #ifndef __HAVE_ARCH_PMDP_INVALIDATE
195 : pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
196 : pmd_t *pmdp)
197 : {
198 : pmd_t old = pmdp_establish(vma, address, pmdp, pmd_mkinvalid(*pmdp));
199 : flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
200 : return old;
201 : }
202 : #endif
203 :
204 : #ifndef __HAVE_ARCH_PMDP_INVALIDATE_AD
205 : pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address,
206 : pmd_t *pmdp)
207 : {
208 : return pmdp_invalidate(vma, address, pmdp);
209 : }
210 : #endif
211 :
212 : #ifndef pmdp_collapse_flush
213 : pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
214 : pmd_t *pmdp)
215 : {
216 : /*
217 : * pmd and hugepage pte format are same. So we could
218 : * use the same function.
219 : */
220 : pmd_t pmd;
221 :
222 : VM_BUG_ON(address & ~HPAGE_PMD_MASK);
223 : VM_BUG_ON(pmd_trans_huge(*pmdp));
224 : pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
225 :
226 : /* collapse entails shooting down ptes not pmd */
227 : flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
228 : return pmd;
229 : }
230 : #endif
231 : #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
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