Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6.git] / mm / pgtable-generic.c
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 #ifndef CONFIG_TRANSPARENT_HUGEPAGE
74         BUG();
75 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
76         VM_BUG_ON(address & ~HPAGE_PMD_MASK);
77         young = pmdp_test_and_clear_young(vma, address, pmdp);
78         if (young)
79                 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
80         return young;
81 }
82 #endif
83
84 #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
85 pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address,
86                        pte_t *ptep)
87 {
88         pte_t pte;
89         pte = ptep_get_and_clear((vma)->vm_mm, address, ptep);
90         flush_tlb_page(vma, address);
91         return pte;
92 }
93 #endif
94
95 #ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
96 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
97 pmd_t pmdp_clear_flush(struct vm_area_struct *vma, unsigned long address,
98                        pmd_t *pmdp)
99 {
100         pmd_t pmd;
101         VM_BUG_ON(address & ~HPAGE_PMD_MASK);
102         pmd = pmdp_get_and_clear(vma->vm_mm, address, pmdp);
103         flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
104         return pmd;
105 }
106 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
107 #endif
108
109 #ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
110 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
111 pmd_t pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
112                            pmd_t *pmdp)
113 {
114         pmd_t pmd = pmd_mksplitting(*pmdp);
115         VM_BUG_ON(address & ~HPAGE_PMD_MASK);
116         set_pmd_at(vma->vm_mm, address, pmdp, pmd);
117         /* tlb flush only to serialize against gup-fast */
118         flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
119 }
120 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
121 #endif