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 <linux/pagemap.h>
14
15#include <asm/domain.h>
16#include <asm/pgtable-hwdef.h>
17#include <asm/processor.h>
18#include <asm/cacheflush.h>
19#include <asm/tlbflush.h>
20
21#define check_pgt_cache() do { } while (0)
22
23#ifdef CONFIG_MMU
24
25#define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
26#define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
27
28/*
29 * Since we have only two-level page tables, these are trivial
30 */
31#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
32#define pmd_free(mm, pmd) do { } while (0)
33#define pgd_populate(mm,pmd,pte) BUG()
34
35extern pgd_t *pgd_alloc(struct mm_struct *mm);
36extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
37
38#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
39
40static inline void clean_pte_table(pte_t *pte)
41{
42 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
43}
44
45/*
46 * Allocate one PTE table.
47 *
48 * This actually allocates two hardware PTE tables, but we wrap this up
49 * into one table thus:
50 *
51 * +------------+
52 * | Linux pt 0 |
53 * +------------+
54 * | Linux pt 1 |
55 * +------------+
56 * | h/w pt 0 |
57 * +------------+
58 * | h/w pt 1 |
59 * +------------+
60 */
61static inline pte_t *
62pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
63{
64 pte_t *pte;
65
66 pte = (pte_t *)__get_free_page(PGALLOC_GFP);
67 if (pte)
68 clean_pte_table(pte);
69
70 return pte;
71}
72
73static inline pgtable_t
74pte_alloc_one(struct mm_struct *mm, unsigned long addr)
75{
76 struct page *pte;
77
78#ifdef CONFIG_HIGHPTE
79 pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
80#else
81 pte = alloc_pages(PGALLOC_GFP, 0);
82#endif
83 if (pte) {
84 if (!PageHighMem(pte))
85 clean_pte_table(page_address(pte));
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 free_page((unsigned long)pte);
99}
100
101static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
102{
103 pgtable_page_dtor(pte);
104 __free_page(pte);
105}
106
107static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
108 pmdval_t prot)
109{
110 pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot;
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 /*
126 * The pmd must be loaded with the physical address of the PTE table
127 */
128 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
129}
130
131static inline void
132pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
133{
134 __pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE);
135}
136#define pmd_pgtable(pmd) pmd_page(pmd)
137
138#endif /* CONFIG_MMU */
139
140#endif