Linux kernel mirror (for testing)
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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#ifdef CONFIG_ARM_LPAE
29
30static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
31{
32 return (pmd_t *)get_zeroed_page(GFP_KERNEL | __GFP_REPEAT);
33}
34
35static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
36{
37 BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
38 free_page((unsigned long)pmd);
39}
40
41static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
42{
43 set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE));
44}
45
46#else /* !CONFIG_ARM_LPAE */
47
48/*
49 * Since we have only two-level page tables, these are trivial
50 */
51#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
52#define pmd_free(mm, pmd) do { } while (0)
53#define pud_populate(mm,pmd,pte) BUG()
54
55#endif /* CONFIG_ARM_LPAE */
56
57extern pgd_t *pgd_alloc(struct mm_struct *mm);
58extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
59
60#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
61
62static inline void clean_pte_table(pte_t *pte)
63{
64 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
65}
66
67/*
68 * Allocate one PTE table.
69 *
70 * This actually allocates two hardware PTE tables, but we wrap this up
71 * into one table thus:
72 *
73 * +------------+
74 * | Linux pt 0 |
75 * +------------+
76 * | Linux pt 1 |
77 * +------------+
78 * | h/w pt 0 |
79 * +------------+
80 * | h/w pt 1 |
81 * +------------+
82 */
83static inline pte_t *
84pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
85{
86 pte_t *pte;
87
88 pte = (pte_t *)__get_free_page(PGALLOC_GFP);
89 if (pte)
90 clean_pte_table(pte);
91
92 return pte;
93}
94
95static inline pgtable_t
96pte_alloc_one(struct mm_struct *mm, unsigned long addr)
97{
98 struct page *pte;
99
100#ifdef CONFIG_HIGHPTE
101 pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
102#else
103 pte = alloc_pages(PGALLOC_GFP, 0);
104#endif
105 if (pte) {
106 if (!PageHighMem(pte))
107 clean_pte_table(page_address(pte));
108 pgtable_page_ctor(pte);
109 }
110
111 return pte;
112}
113
114/*
115 * Free one PTE table.
116 */
117static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
118{
119 if (pte)
120 free_page((unsigned long)pte);
121}
122
123static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
124{
125 pgtable_page_dtor(pte);
126 __free_page(pte);
127}
128
129static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
130 pmdval_t prot)
131{
132 pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot;
133 pmdp[0] = __pmd(pmdval);
134#ifndef CONFIG_ARM_LPAE
135 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
136#endif
137 flush_pmd_entry(pmdp);
138}
139
140/*
141 * Populate the pmdp entry with a pointer to the pte. This pmd is part
142 * of the mm address space.
143 *
144 * Ensure that we always set both PMD entries.
145 */
146static inline void
147pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
148{
149 /*
150 * The pmd must be loaded with the physical address of the PTE table
151 */
152 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
153}
154
155static inline void
156pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
157{
158 __pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE);
159}
160#define pmd_pgtable(pmd) pmd_page(pmd)
161
162#endif /* CONFIG_MMU */
163
164#endif