Linux kernel mirror (for testing)
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linux
1/*
2 * arch/arm/include/asm/pgalloc.h
3 *
4 * Copyright (C) 2000-2001 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#ifndef _ASMARM_PGALLOC_H
11#define _ASMARM_PGALLOC_H
12
13#include <asm/domain.h>
14#include <asm/pgtable-hwdef.h>
15#include <asm/processor.h>
16#include <asm/cacheflush.h>
17#include <asm/tlbflush.h>
18
19#define check_pgt_cache() do { } while (0)
20
21#ifdef CONFIG_MMU
22
23#define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
24#define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
25
26/*
27 * Since we have only two-level page tables, these are trivial
28 */
29#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
30#define pmd_free(mm, pmd) do { } while (0)
31#define pgd_populate(mm,pmd,pte) BUG()
32
33extern pgd_t *get_pgd_slow(struct mm_struct *mm);
34extern void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd);
35
36#define pgd_alloc(mm) get_pgd_slow(mm)
37#define pgd_free(mm, pgd) free_pgd_slow(mm, pgd)
38
39#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
40
41/*
42 * Allocate one PTE table.
43 *
44 * This actually allocates two hardware PTE tables, but we wrap this up
45 * into one table thus:
46 *
47 * +------------+
48 * | h/w pt 0 |
49 * +------------+
50 * | h/w pt 1 |
51 * +------------+
52 * | Linux pt 0 |
53 * +------------+
54 * | Linux pt 1 |
55 * +------------+
56 */
57static inline pte_t *
58pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
59{
60 pte_t *pte;
61
62 pte = (pte_t *)__get_free_page(PGALLOC_GFP);
63 if (pte) {
64 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE);
65 pte += PTRS_PER_PTE;
66 }
67
68 return pte;
69}
70
71static inline pgtable_t
72pte_alloc_one(struct mm_struct *mm, unsigned long addr)
73{
74 struct page *pte;
75
76#ifdef CONFIG_HIGHPTE
77 pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
78#else
79 pte = alloc_pages(PGALLOC_GFP, 0);
80#endif
81 if (pte) {
82 if (!PageHighMem(pte)) {
83 void *page = page_address(pte);
84 clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
85 }
86 pgtable_page_ctor(pte);
87 }
88
89 return pte;
90}
91
92/*
93 * Free one PTE table.
94 */
95static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
96{
97 if (pte) {
98 pte -= PTRS_PER_PTE;
99 free_page((unsigned long)pte);
100 }
101}
102
103static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
104{
105 pgtable_page_dtor(pte);
106 __free_page(pte);
107}
108
109static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval)
110{
111 pmdp[0] = __pmd(pmdval);
112 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
113 flush_pmd_entry(pmdp);
114}
115
116/*
117 * Populate the pmdp entry with a pointer to the pte. This pmd is part
118 * of the mm address space.
119 *
120 * Ensure that we always set both PMD entries.
121 */
122static inline void
123pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
124{
125 unsigned long pte_ptr = (unsigned long)ptep;
126
127 /*
128 * The pmd must be loaded with the physical
129 * address of the PTE table
130 */
131 pte_ptr -= PTRS_PER_PTE * sizeof(void *);
132 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE);
133}
134
135static inline void
136pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
137{
138 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE);
139}
140#define pmd_pgtable(pmd) pmd_page(pmd)
141
142#endif /* CONFIG_MMU */
143
144#endif