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(pmd) do { } while (0)
31 #define pgd_populate(mm,pmd,pte) BUG()
32
33 extern pgd_t *get_pgd_slow(struct mm_struct *mm);
34 extern void free_pgd_slow(pgd_t *pgd);
35
36 #define pgd_alloc(mm) get_pgd_slow(mm)
37 #define pgd_free(pgd) free_pgd_slow(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 */
55 static inline pte_t *
pte_alloc_one_kernel(struct mm_struct * mm,unsigned long addr)56 pte_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
69 static inline struct page *
pte_alloc_one(struct mm_struct * mm,unsigned long addr)70 pte_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 }
79
80 return pte;
81 }
82
83 /*
84 * Free one PTE table.
85 */
pte_free_kernel(pte_t * pte)86 static inline void pte_free_kernel(pte_t *pte)
87 {
88 if (pte) {
89 pte -= PTRS_PER_PTE;
90 free_page((unsigned long)pte);
91 }
92 }
93
pte_free(struct page * pte)94 static inline void pte_free(struct page *pte)
95 {
96 __free_page(pte);
97 }
98
__pmd_populate(pmd_t * pmdp,unsigned long pmdval)99 static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval)
100 {
101 pmdp[0] = __pmd(pmdval);
102 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
103 flush_pmd_entry(pmdp);
104 }
105
106 /*
107 * Populate the pmdp entry with a pointer to the pte. This pmd is part
108 * of the mm address space.
109 *
110 * Ensure that we always set both PMD entries.
111 */
112 static inline void
pmd_populate_kernel(struct mm_struct * mm,pmd_t * pmdp,pte_t * ptep)113 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
114 {
115 unsigned long pte_ptr = (unsigned long)ptep;
116
117 /*
118 * The pmd must be loaded with the physical
119 * address of the PTE table
120 */
121 pte_ptr -= PTRS_PER_PTE * sizeof(void *);
122 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE);
123 }
124
125 static inline void
pmd_populate(struct mm_struct * mm,pmd_t * pmdp,struct page * ptep)126 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, struct page *ptep)
127 {
128 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE);
129 }
130
131 #endif /* CONFIG_MMU */
132
133 #endif
134