summaryrefslogtreecommitdiffstats
path: root/arch/arm/include/asm/pgalloc.h
blob: 2d7344f0e2085b2a72da34f04fc3264e88834b3a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
/*
 *  arch/arm/include/asm/pgalloc.h
 *
 *  Copyright (C) 2000-2001 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef _ASMARM_PGALLOC_H
#define _ASMARM_PGALLOC_H

#include <linux/pagemap.h>

#include <asm/domain.h>
#include <asm/pgtable-hwdef.h>
#include <asm/processor.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>

#define check_pgt_cache()		do { } while (0)

#ifdef CONFIG_MMU

#define _PAGE_USER_TABLE	(PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
#define _PAGE_KERNEL_TABLE	(PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))

#ifdef CONFIG_ARM_LPAE

static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
{
	return (pmd_t *)get_zeroed_page(GFP_KERNEL);
}

static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
	BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
	free_page((unsigned long)pmd);
}

static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
{
	set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE));
}

#else	/* !CONFIG_ARM_LPAE */

/*
 * Since we have only two-level page tables, these are trivial
 */
#define pmd_alloc_one(mm,addr)		({ BUG(); ((pmd_t *)2); })
#define pmd_free(mm, pmd)		do { } while (0)
#define pud_populate(mm,pmd,pte)	BUG()

#endif	/* CONFIG_ARM_LPAE */

extern pgd_t *pgd_alloc(struct mm_struct *mm);
extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);

#define PGALLOC_GFP	(GFP_KERNEL | __GFP_ZERO)

static inline void clean_pte_table(pte_t *pte)
{
	clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
}

/*
 * Allocate one PTE table.
 *
 * This actually allocates two hardware PTE tables, but we wrap this up
 * into one table thus:
 *
 *  +------------+
 *  | Linux pt 0 |
 *  +------------+
 *  | Linux pt 1 |
 *  +------------+
 *  |  h/w pt 0  |
 *  +------------+
 *  |  h/w pt 1  |
 *  +------------+
 */
static inline pte_t *
pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
{
	pte_t *pte;

	pte = (pte_t *)__get_free_page(PGALLOC_GFP);
	if (pte)
		clean_pte_table(pte);

	return pte;
}

static inline pgtable_t
pte_alloc_one(struct mm_struct *mm, unsigned long addr)
{
	struct page *pte;

#ifdef CONFIG_HIGHPTE
	pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
#else
	pte = alloc_pages(PGALLOC_GFP, 0);
#endif
	if (!pte)
		return NULL;
	if (!PageHighMem(pte))
		clean_pte_table(page_address(pte));
	if (!pgtable_page_ctor(pte)) {
		__free_page(pte);
		return NULL;
	}
	return pte;
}

/*
 * Free one PTE table.
 */
static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
	if (pte)
		free_page((unsigned long)pte);
}

static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
{
	pgtable_page_dtor(pte);
	__free_page(pte);
}

static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
				  pmdval_t prot)
{
	pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot;
	pmdp[0] = __pmd(pmdval);
#ifndef CONFIG_ARM_LPAE
	pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
#endif
	flush_pmd_entry(pmdp);
}

/*
 * Populate the pmdp entry with a pointer to the pte.  This pmd is part
 * of the mm address space.
 *
 * Ensure that we always set both PMD entries.
 */
static inline void
pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
{
	/*
	 * The pmd must be loaded with the physical address of the PTE table
	 */
	__pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
}

static inline void
pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
{
	extern pmdval_t user_pmd_table;
	pmdval_t prot;

	if (__LINUX_ARM_ARCH__ >= 6 && !IS_ENABLED(CONFIG_ARM_LPAE))
		prot = user_pmd_table;
	else
		prot = _PAGE_USER_TABLE;

	__pmd_populate(pmdp, page_to_phys(ptep), prot);
}
#define pmd_pgtable(pmd) pmd_page(pmd)

#endif /* CONFIG_MMU */

#endif
OpenPOWER on IntegriCloud