Linux kernel mirror (for testing)
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linux
1/*
2 * linux/include/asm-arm/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/*
40 * Allocate one PTE table.
41 *
42 * This actually allocates two hardware PTE tables, but we wrap this up
43 * into one table thus:
44 *
45 * +------------+
46 * | h/w pt 0 |
47 * +------------+
48 * | h/w pt 1 |
49 * +------------+
50 * | Linux pt 0 |
51 * +------------+
52 * | Linux pt 1 |
53 * +------------+
54 */
55static inline pte_t *
56pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
57{
58 pte_t *pte;
59
60 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
61 if (pte) {
62 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE);
63 pte += PTRS_PER_PTE;
64 }
65
66 return pte;
67}
68
69static inline pgtable_t
70pte_alloc_one(struct mm_struct *mm, unsigned long addr)
71{
72 struct page *pte;
73
74 pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
75 if (pte) {
76 void *page = page_address(pte);
77 clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
78 pgtable_page_ctor(pte);
79 }
80
81 return pte;
82}
83
84/*
85 * Free one PTE table.
86 */
87static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
88{
89 if (pte) {
90 pte -= PTRS_PER_PTE;
91 free_page((unsigned long)pte);
92 }
93}
94
95static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
96{
97 pgtable_page_dtor(pte);
98 __free_page(pte);
99}
100
101static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval)
102{
103 pmdp[0] = __pmd(pmdval);
104 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
105 flush_pmd_entry(pmdp);
106}
107
108/*
109 * Populate the pmdp entry with a pointer to the pte. This pmd is part
110 * of the mm address space.
111 *
112 * Ensure that we always set both PMD entries.
113 */
114static inline void
115pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
116{
117 unsigned long pte_ptr = (unsigned long)ptep;
118
119 /*
120 * The pmd must be loaded with the physical
121 * address of the PTE table
122 */
123 pte_ptr -= PTRS_PER_PTE * sizeof(void *);
124 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE);
125}
126
127static inline void
128pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
129{
130 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE);
131}
132#define pmd_pgtable(pmd) pmd_page(pmd)
133
134#endif /* CONFIG_MMU */
135
136#endif