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8#include <linux/mm.h>
9#include <linux/hugetlb.h>
10
11
12void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
13 pte_t *pteptr, pte_t pteval)
14{
15 pmd_t *pmdp = (pmd_t *) pteptr;
16 pte_t shadow_pteval = pteval;
17 unsigned long mask;
18
19 if (!MACHINE_HAS_HPAGE) {
20 pteptr = (pte_t *) pte_page(pteval)[1].index;
21 mask = pte_val(pteval) &
22 (_SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO);
23 pte_val(pteval) = (_SEGMENT_ENTRY + __pa(pteptr)) | mask;
24 if (mm->context.noexec) {
25 pteptr += PTRS_PER_PTE;
26 pte_val(shadow_pteval) =
27 (_SEGMENT_ENTRY + __pa(pteptr)) | mask;
28 }
29 }
30
31 pmd_val(*pmdp) = pte_val(pteval);
32 if (mm->context.noexec) {
33 pmdp = get_shadow_table(pmdp);
34 pmd_val(*pmdp) = pte_val(shadow_pteval);
35 }
36}
37
38int arch_prepare_hugepage(struct page *page)
39{
40 unsigned long addr = page_to_phys(page);
41 pte_t pte;
42 pte_t *ptep;
43 int i;
44
45 if (MACHINE_HAS_HPAGE)
46 return 0;
47
48 ptep = (pte_t *) pte_alloc_one(&init_mm, address);
49 if (!ptep)
50 return -ENOMEM;
51
52 pte = mk_pte(page, PAGE_RW);
53 for (i = 0; i < PTRS_PER_PTE; i++) {
54 set_pte_at(&init_mm, addr + i * PAGE_SIZE, ptep + i, pte);
55 pte_val(pte) += PAGE_SIZE;
56 }
57 page[1].index = (unsigned long) ptep;
58 return 0;
59}
60
61void arch_release_hugepage(struct page *page)
62{
63 pte_t *ptep;
64
65 if (MACHINE_HAS_HPAGE)
66 return;
67
68 ptep = (pte_t *) page[1].index;
69 if (!ptep)
70 return;
71 pte_free(&init_mm, ptep);
72 page[1].index = 0;
73}
74
75pte_t *huge_pte_alloc(struct mm_struct *mm,
76 unsigned long addr, unsigned long sz)
77{
78 pgd_t *pgdp;
79 pud_t *pudp;
80 pmd_t *pmdp = NULL;
81
82 pgdp = pgd_offset(mm, addr);
83 pudp = pud_alloc(mm, pgdp, addr);
84 if (pudp)
85 pmdp = pmd_alloc(mm, pudp, addr);
86 return (pte_t *) pmdp;
87}
88
89pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
90{
91 pgd_t *pgdp;
92 pud_t *pudp;
93 pmd_t *pmdp = NULL;
94
95 pgdp = pgd_offset(mm, addr);
96 if (pgd_present(*pgdp)) {
97 pudp = pud_offset(pgdp, addr);
98 if (pud_present(*pudp))
99 pmdp = pmd_offset(pudp, addr);
100 }
101 return (pte_t *) pmdp;
102}
103
104int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
105{
106 return 0;
107}
108
109struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
110 int write)
111{
112 return ERR_PTR(-EINVAL);
113}
114
115int pmd_huge(pmd_t pmd)
116{
117 if (!MACHINE_HAS_HPAGE)
118 return 0;
119
120 return !!(pmd_val(pmd) & _SEGMENT_ENTRY_LARGE);
121}
122
123int pud_huge(pud_t pud)
124{
125 return 0;
126}
127
128struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
129 pmd_t *pmdp, int write)
130{
131 struct page *page;
132
133 if (!MACHINE_HAS_HPAGE)
134 return NULL;
135
136 page = pmd_page(*pmdp);
137 if (page)
138 page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
139 return page;
140}
141
