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Andrea Arcangelie2cda322011-01-13 15:46:40 -08001/*
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
Andrew Mortonf95ba942011-01-25 15:07:11 -08009#include <linux/pagemap.h>
Andrea Arcangelie2cda322011-01-13 15:46:40 -080010#include <asm/tlb.h>
11#include <asm-generic/pgtable.h>
12
Joonsoo Kimbc4b4442013-09-11 14:21:28 -070013/*
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
Andrea Arcangelie2cda322011-01-13 15:46:40 -080037#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
38/*
Rik van Rielcef23d92012-11-06 09:56:01 +000039 * Only sets the access flags (dirty, accessed), as well as write
40 * permission. Furthermore, we know it always gets set to a "more
Andrea Arcangelie2cda322011-01-13 15:46:40 -080041 * 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);
Rik van Rielcef23d92012-11-06 09:56:01 +000054 flush_tlb_fix_spurious_fault(vma, address);
Andrea Arcangelie2cda322011-01-13 15:46:40 -080055 }
56 return changed;
57}
58#endif
59
Vineet Gupta52585bc2015-07-09 17:19:30 +053060#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
61int ptep_clear_flush_young(struct vm_area_struct *vma,
62 unsigned long address, pte_t *ptep)
63{
64 int young;
65 young = ptep_test_and_clear_young(vma, address, ptep);
66 if (young)
67 flush_tlb_page(vma, address);
68 return young;
69}
70#endif
71
72#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
73pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
74 pte_t *ptep)
75{
76 struct mm_struct *mm = (vma)->vm_mm;
77 pte_t pte;
78 pte = ptep_get_and_clear(mm, address, ptep);
79 if (pte_accessible(mm, pte))
80 flush_tlb_page(vma, address);
81 return pte;
82}
83#endif
84
Vineet Guptabd5e88a2015-07-09 17:22:44 +053085#ifdef CONFIG_TRANSPARENT_HUGEPAGE
86
Vineet Gupta12ebc152015-02-20 10:36:28 +053087#ifndef __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
88
89/*
90 * ARCHes with special requirements for evicting THP backing TLB entries can
91 * implement this. Otherwise also, it can help optimize normal TLB flush in
92 * THP regime. stock flush_tlb_range() typically has optimization to nuke the
93 * entire TLB TLB if flush span is greater than a threshhold, which will
94 * likely be true for a single huge page. Thus a single thp flush will
95 * invalidate the entire TLB which is not desitable.
96 * e.g. see arch/arc: flush_pmd_tlb_range
97 */
98#define flush_pmd_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end)
99#endif
100
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800101#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
102int pmdp_set_access_flags(struct vm_area_struct *vma,
103 unsigned long address, pmd_t *pmdp,
104 pmd_t entry, int dirty)
105{
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800106 int changed = !pmd_same(*pmdp, entry);
107 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
108 if (changed) {
109 set_pmd_at(vma->vm_mm, address, pmdp, entry);
Vineet Gupta12ebc152015-02-20 10:36:28 +0530110 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800111 }
112 return changed;
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800113}
114#endif
115
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800116#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
117int pmdp_clear_flush_young(struct vm_area_struct *vma,
118 unsigned long address, pmd_t *pmdp)
119{
120 int young;
Naoya Horiguchid8c37c42012-03-21 16:34:27 -0700121 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800122 young = pmdp_test_and_clear_young(vma, address, pmdp);
123 if (young)
Vineet Gupta12ebc152015-02-20 10:36:28 +0530124 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800125 return young;
126}
127#endif
128
Aneesh Kumar K.V8809aa22015-06-24 16:57:44 -0700129#ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH
Aneesh Kumar K.V8809aa22015-06-24 16:57:44 -0700130pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address,
131 pmd_t *pmdp)
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800132{
133 pmd_t pmd;
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800134 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
Aneesh Kumar K.Vf28b6ff2015-06-24 16:57:42 -0700135 VM_BUG_ON(!pmd_trans_huge(*pmdp));
Aneesh Kumar K.V8809aa22015-06-24 16:57:44 -0700136 pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
Vineet Gupta12ebc152015-02-20 10:36:28 +0530137 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800138 return pmd;
139}
140#endif
141
142#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
Chris Metcalf73636b12012-03-28 13:59:18 -0400143void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
144 pmd_t *pmdp)
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800145{
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800146 pmd_t pmd = pmd_mksplitting(*pmdp);
147 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
148 set_pmd_at(vma->vm_mm, address, pmdp, pmd);
149 /* tlb flush only to serialize against gup-fast */
Vineet Gupta12ebc152015-02-20 10:36:28 +0530150 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800151}
Andrea Arcangelie2cda322011-01-13 15:46:40 -0800152#endif
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700153
154#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
Aneesh Kumar K.V6b0b50b2013-06-05 17:14:02 -0700155void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
156 pgtable_t pgtable)
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700157{
Kirill A. Shutemovc4088eb2013-11-14 14:31:04 -0800158 assert_spin_locked(pmd_lockptr(mm, pmdp));
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700159
160 /* FIFO */
Kirill A. Shutemovc389a252013-11-14 14:30:59 -0800161 if (!pmd_huge_pte(mm, pmdp))
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700162 INIT_LIST_HEAD(&pgtable->lru);
163 else
Kirill A. Shutemovc389a252013-11-14 14:30:59 -0800164 list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru);
165 pmd_huge_pte(mm, pmdp) = pgtable;
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700166}
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700167#endif
168
169#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700170/* no "address" argument so destroys page coloring of some arch */
Aneesh Kumar K.V6b0b50b2013-06-05 17:14:02 -0700171pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700172{
173 pgtable_t pgtable;
174
Kirill A. Shutemovc4088eb2013-11-14 14:31:04 -0800175 assert_spin_locked(pmd_lockptr(mm, pmdp));
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700176
177 /* FIFO */
Kirill A. Shutemovc389a252013-11-14 14:30:59 -0800178 pgtable = pmd_huge_pte(mm, pmdp);
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700179 if (list_empty(&pgtable->lru))
Kirill A. Shutemovc389a252013-11-14 14:30:59 -0800180 pmd_huge_pte(mm, pmdp) = NULL;
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700181 else {
Kirill A. Shutemovc389a252013-11-14 14:30:59 -0800182 pmd_huge_pte(mm, pmdp) = list_entry(pgtable->lru.next,
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700183 struct page, lru);
184 list_del(&pgtable->lru);
185 }
186 return pgtable;
187}
Gerald Schaefere3ebcf62012-10-08 16:30:07 -0700188#endif
Gerald Schaefer46dcde72012-10-08 16:30:09 -0700189
190#ifndef __HAVE_ARCH_PMDP_INVALIDATE
Gerald Schaefer46dcde72012-10-08 16:30:09 -0700191void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
192 pmd_t *pmdp)
193{
Mel Gorman67f87462013-12-18 17:08:34 -0800194 pmd_t entry = *pmdp;
Matthew Wilcoxce8369b2014-08-29 15:18:33 -0700195 set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(entry));
Vineet Gupta12ebc152015-02-20 10:36:28 +0530196 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
Gerald Schaefer46dcde72012-10-08 16:30:09 -0700197}
Gerald Schaefer46dcde72012-10-08 16:30:09 -0700198#endif
Aneesh Kumar K.Vf28b6ff2015-06-24 16:57:42 -0700199
200#ifndef pmdp_collapse_flush
Aneesh Kumar K.Vf28b6ff2015-06-24 16:57:42 -0700201pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address,
202 pmd_t *pmdp)
203{
Aneesh Kumar K.V8809aa22015-06-24 16:57:44 -0700204 /*
205 * pmd and hugepage pte format are same. So we could
206 * use the same function.
207 */
Aneesh Kumar K.Vf28b6ff2015-06-24 16:57:42 -0700208 pmd_t pmd;
209
210 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
211 VM_BUG_ON(pmd_trans_huge(*pmdp));
Aneesh Kumar K.V8809aa22015-06-24 16:57:44 -0700212 pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
Vineet Gupta12ebc152015-02-20 10:36:28 +0530213 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
Aneesh Kumar K.Vf28b6ff2015-06-24 16:57:42 -0700214 return pmd;
215}
Aneesh Kumar K.Vf28b6ff2015-06-24 16:57:42 -0700216#endif
Vineet Guptabd5e88a2015-07-09 17:22:44 +0530217#endif /* CONFIG_TRANSPARENT_HUGEPAGE */