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/processor.h>
14#include <asm/cacheflush.h>
15#include <asm/tlbflush.h>
16
17/*
18 * Since we have only two-level page tables, these are trivial
19 */
20#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
21#define pmd_free(pmd) do { } while (0)
22#define pgd_populate(mm,pmd,pte) BUG()
23
24extern pgd_t *get_pgd_slow(struct mm_struct *mm);
25extern void free_pgd_slow(pgd_t *pgd);
26
27#define pgd_alloc(mm) get_pgd_slow(mm)
28#define pgd_free(pgd) free_pgd_slow(pgd)
29
30#define check_pgt_cache() do { } while (0)
31
32/*
33 * Allocate one PTE table.
34 *
35 * This actually allocates two hardware PTE tables, but we wrap this up
36 * into one table thus:
37 *
38 * +------------+
39 * | h/w pt 0 |
40 * +------------+
41 * | h/w pt 1 |
42 * +------------+
43 * | Linux pt 0 |
44 * +------------+
45 * | Linux pt 1 |
46 * +------------+
47 */
48static inline pte_t *
49pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
50{
51 pte_t *pte;
52
53 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
54 if (pte) {
55 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE);
56 pte += PTRS_PER_PTE;
57 }
58
59 return pte;
60}
61
62static inline struct page *
63pte_alloc_one(struct mm_struct *mm, unsigned long addr)
64{
65 struct page *pte;
66
67 pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
68 if (pte) {
69 void *page = page_address(pte);
70 clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
71 }
72
73 return pte;
74}
75
76/*
77 * Free one PTE table.
78 */
79static inline void pte_free_kernel(pte_t *pte)
80{
81 if (pte) {
82 pte -= PTRS_PER_PTE;
83 free_page((unsigned long)pte);
84 }
85}
86
87static inline void pte_free(struct page *pte)
88{
89 __free_page(pte);
90}
91
92static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval)
93{
94 pmdp[0] = __pmd(pmdval);
95 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
96 flush_pmd_entry(pmdp);
97}
98
99/*
100 * Populate the pmdp entry with a pointer to the pte. This pmd is part
101 * of the mm address space.
102 *
103 * Ensure that we always set both PMD entries.
104 */
105static inline void
106pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
107{
108 unsigned long pte_ptr = (unsigned long)ptep;
109
110 /*
111 * The pmd must be loaded with the physical
112 * address of the PTE table
113 */
114 pte_ptr -= PTRS_PER_PTE * sizeof(void *);
115 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE);
116}
117
118static inline void
119pmd_populate(struct mm_struct *mm, pmd_t *pmdp, struct page *ptep)
120{
121 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE);
122}
123
124#endif