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 *pgd_alloc(struct mm_struct *mm);
34extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
35
36#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
37
38static inline void clean_pte_table(pte_t *pte)
39{
40 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
41}
42
43/*
44 * Allocate one PTE table.
45 *
46 * This actually allocates two hardware PTE tables, but we wrap this up
47 * into one table thus:
48 *
49 * +------------+
50 * | Linux pt 0 |
51 * +------------+
52 * | Linux pt 1 |
53 * +------------+
54 * | h/w pt 0 |
55 * +------------+
56 * | h/w pt 1 |
57 * +------------+
58 */
59static inline pte_t *
60pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
61{
62 pte_t *pte;
63
64 pte = (pte_t *)__get_free_page(PGALLOC_GFP);
65 if (pte)
66 clean_pte_table(pte);
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 clean_pte_table(page_address(pte));
84 pgtable_page_ctor(pte);
85 }
86
87 return pte;
88}
89
90/*
91 * Free one PTE table.
92 */
93static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
94{
95 if (pte)
96 free_page((unsigned long)pte);
97}
98
99static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
100{
101 pgtable_page_dtor(pte);
102 __free_page(pte);
103}
104
105static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
106 unsigned long prot)
107{
108 unsigned long pmdval = (pte + PTE_HWTABLE_OFF) | prot;
109 pmdp[0] = __pmd(pmdval);
110 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
111 flush_pmd_entry(pmdp);
112}
113
114/*
115 * Populate the pmdp entry with a pointer to the pte. This pmd is part
116 * of the mm address space.
117 *
118 * Ensure that we always set both PMD entries.
119 */
120static inline void
121pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
122{
123 /*
124 * The pmd must be loaded with the physical address of the PTE table
125 */
126 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
127}
128
129static inline void
130pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
131{
132 __pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE);
133}
134#define pmd_pgtable(pmd) pmd_page(pmd)
135
136#endif /* CONFIG_MMU */
137
138#endif