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 _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
20#define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
21
22/*
23 * Since we have only two-level page tables, these are trivial
24 */
25#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
26#define pmd_free(pmd) do { } while (0)
27#define pgd_populate(mm,pmd,pte) BUG()
28
29extern pgd_t *get_pgd_slow(struct mm_struct *mm);
30extern void free_pgd_slow(pgd_t *pgd);
31
32#define pgd_alloc(mm) get_pgd_slow(mm)
33#define pgd_free(pgd) free_pgd_slow(pgd)
34
35#define check_pgt_cache() do { } while (0)
36
37/*
38 * Allocate one PTE table.
39 *
40 * This actually allocates two hardware PTE tables, but we wrap this up
41 * into one table thus:
42 *
43 * +------------+
44 * | h/w pt 0 |
45 * +------------+
46 * | h/w pt 1 |
47 * +------------+
48 * | Linux pt 0 |
49 * +------------+
50 * | Linux pt 1 |
51 * +------------+
52 */
53static inline pte_t *
54pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
55{
56 pte_t *pte;
57
58 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
59 if (pte) {
60 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE);
61 pte += PTRS_PER_PTE;
62 }
63
64 return pte;
65}
66
67static inline struct page *
68pte_alloc_one(struct mm_struct *mm, unsigned long addr)
69{
70 struct page *pte;
71
72 pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
73 if (pte) {
74 void *page = page_address(pte);
75 clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
76 }
77
78 return pte;
79}
80
81/*
82 * Free one PTE table.
83 */
84static inline void pte_free_kernel(pte_t *pte)
85{
86 if (pte) {
87 pte -= PTRS_PER_PTE;
88 free_page((unsigned long)pte);
89 }
90}
91
92static inline void pte_free(struct page *pte)
93{
94 __free_page(pte);
95}
96
97static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval)
98{
99 pmdp[0] = __pmd(pmdval);
100 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
101 flush_pmd_entry(pmdp);
102}
103
104/*
105 * Populate the pmdp entry with a pointer to the pte. This pmd is part
106 * of the mm address space.
107 *
108 * Ensure that we always set both PMD entries.
109 */
110static inline void
111pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
112{
113 unsigned long pte_ptr = (unsigned long)ptep;
114
115 /*
116 * The pmd must be loaded with the physical
117 * address of the PTE table
118 */
119 pte_ptr -= PTRS_PER_PTE * sizeof(void *);
120 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE);
121}
122
123static inline void
124pmd_populate(struct mm_struct *mm, pmd_t *pmdp, struct page *ptep)
125{
126 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE);
127}
128
129#endif