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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
nios2: Page table management
This patch adds support for page table management.
Signed-off-by: Ley Foon Tan <lftan@altera.com>
+505
+86
arch/nios2/include/asm/pgalloc.h
+86
arch/nios2/include/asm/pgalloc.h
···
1
+
/*
2
+
* This file is subject to the terms and conditions of the GNU General Public
3
+
* License. See the file "COPYING" in the main directory of this archive
4
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* for more details.
5
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*
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* Copyright (C) 1994 - 2001, 2003 by Ralf Baechle
7
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* Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
8
+
*/
9
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10
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#ifndef _ASM_NIOS2_PGALLOC_H
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#define _ASM_NIOS2_PGALLOC_H
12
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13
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#include <linux/mm.h>
14
+
15
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static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
16
+
pte_t *pte)
17
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{
18
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set_pmd(pmd, __pmd((unsigned long)pte));
19
+
}
20
+
21
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static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
22
+
pgtable_t pte)
23
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{
24
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set_pmd(pmd, __pmd((unsigned long)page_address(pte)));
25
+
}
26
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#define pmd_pgtable(pmd) pmd_page(pmd)
27
+
28
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/*
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* Initialize a new pmd table with invalid pointers.
30
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*/
31
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extern void pmd_init(unsigned long page, unsigned long pagetable);
32
+
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extern pgd_t *pgd_alloc(struct mm_struct *mm);
34
+
35
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static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
36
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{
37
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free_pages((unsigned long)pgd, PGD_ORDER);
38
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}
39
+
40
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static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
41
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unsigned long address)
42
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{
43
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pte_t *pte;
44
+
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pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO,
46
+
PTE_ORDER);
47
+
48
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return pte;
49
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}
50
+
51
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static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
52
+
unsigned long address)
53
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{
54
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struct page *pte;
55
+
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pte = alloc_pages(GFP_KERNEL | __GFP_REPEAT, PTE_ORDER);
57
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if (pte) {
58
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if (!pgtable_page_ctor(pte)) {
59
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__free_page(pte);
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return NULL;
61
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}
62
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clear_highpage(pte);
63
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}
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return pte;
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}
66
+
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static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
68
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{
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free_pages((unsigned long)pte, PTE_ORDER);
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}
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+
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static inline void pte_free(struct mm_struct *mm, struct page *pte)
73
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{
74
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pgtable_page_dtor(pte);
75
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__free_pages(pte, PTE_ORDER);
76
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}
77
+
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#define __pte_free_tlb(tlb, pte, addr) \
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do { \
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pgtable_page_dtor(pte); \
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tlb_remove_page((tlb), (pte)); \
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} while (0)
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+
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#define check_pgt_cache() do { } while (0)
85
+
86
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#endif /* _ASM_NIOS2_PGALLOC_H */
+35
arch/nios2/include/asm/pgtable-bits.h
+35
arch/nios2/include/asm/pgtable-bits.h
···
1
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/*
2
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* Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
3
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* Copyright (C) 2009 Wind River Systems Inc
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
7
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* for more details.
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*/
9
+
10
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#ifndef _ASM_NIOS2_PGTABLE_BITS_H
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#define _ASM_NIOS2_PGTABLE_BITS_H
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+
13
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/*
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* These are actual hardware defined protection bits in the tlbacc register
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* which looks like this:
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*
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* 31 30 ... 26 25 24 23 22 21 20 19 18 ... 1 0
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* ignored........ C R W X G PFN............
19
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*/
20
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#define _PAGE_GLOBAL (1<<20)
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#define _PAGE_EXEC (1<<21)
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#define _PAGE_WRITE (1<<22)
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#define _PAGE_READ (1<<23)
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#define _PAGE_CACHED (1<<24) /* C: data access cacheable */
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+
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/*
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* Software defined bits. They are ignored by the hardware and always read back
28
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* as zero, but can be written as non-zero.
29
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*/
30
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#define _PAGE_PRESENT (1<<25) /* PTE contains a translation */
31
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#define _PAGE_ACCESSED (1<<26) /* page referenced */
32
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#define _PAGE_DIRTY (1<<27) /* dirty page */
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#define _PAGE_FILE (1<<28) /* PTE used for file mapping or swap */
34
+
35
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#endif /* _ASM_NIOS2_PGTABLE_BITS_H */
+310
arch/nios2/include/asm/pgtable.h
+310
arch/nios2/include/asm/pgtable.h
···
1
+
/*
2
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* Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
3
+
* Copyright (C) 2009 Wind River Systems Inc
4
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*
5
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* Based on asm/pgtable-32.h from mips which is:
6
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*
7
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* Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
8
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* Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
9
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*
10
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* This file is subject to the terms and conditions of the GNU General Public
11
+
* License. See the file "COPYING" in the main directory of this archive
12
+
* for more details.
13
+
*/
14
+
15
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#ifndef _ASM_NIOS2_PGTABLE_H
16
+
#define _ASM_NIOS2_PGTABLE_H
17
+
18
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#include <linux/io.h>
19
+
#include <linux/bug.h>
20
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#include <asm/page.h>
21
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#include <asm/cacheflush.h>
22
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#include <asm/tlbflush.h>
23
+
24
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#include <asm/pgtable-bits.h>
25
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#include <asm-generic/pgtable-nopmd.h>
26
+
27
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#define FIRST_USER_ADDRESS 0
28
+
29
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#define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
30
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#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
31
+
32
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struct mm_struct;
33
+
34
+
/* Helper macro */
35
+
#define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED | \
36
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((x) ? _PAGE_EXEC : 0) | \
37
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((r) ? _PAGE_READ : 0) | \
38
+
((w) ? _PAGE_WRITE : 0))
39
+
/*
40
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* These are the macros that generic kernel code needs
41
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* (to populate protection_map[])
42
+
*/
43
+
44
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/* Remove W bit on private pages for COW support */
45
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#define __P000 MKP(0, 0, 0)
46
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#define __P001 MKP(0, 0, 1)
47
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#define __P010 MKP(0, 0, 0) /* COW */
48
+
#define __P011 MKP(0, 0, 1) /* COW */
49
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#define __P100 MKP(1, 0, 0)
50
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#define __P101 MKP(1, 0, 1)
51
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#define __P110 MKP(1, 0, 0) /* COW */
52
+
#define __P111 MKP(1, 0, 1) /* COW */
53
+
54
+
/* Shared pages can have exact HW mapping */
55
+
#define __S000 MKP(0, 0, 0)
56
+
#define __S001 MKP(0, 0, 1)
57
+
#define __S010 MKP(0, 1, 0)
58
+
#define __S011 MKP(0, 1, 1)
59
+
#define __S100 MKP(1, 0, 0)
60
+
#define __S101 MKP(1, 0, 1)
61
+
#define __S110 MKP(1, 1, 0)
62
+
#define __S111 MKP(1, 1, 1)
63
+
64
+
/* Used all over the kernel */
65
+
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
66
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_PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL)
67
+
68
+
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
69
+
_PAGE_WRITE | _PAGE_ACCESSED)
70
+
71
+
#define PAGE_COPY MKP(0, 0, 1)
72
+
73
+
#define PGD_ORDER 0
74
+
#define PTE_ORDER 0
75
+
76
+
#define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
77
+
#define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
78
+
79
+
#define USER_PTRS_PER_PGD \
80
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(CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE)
81
+
82
+
#define PGDIR_SHIFT 22
83
+
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
84
+
#define PGDIR_MASK (~(PGDIR_SIZE-1))
85
+
86
+
/*
87
+
* ZERO_PAGE is a global shared page that is always zero: used
88
+
* for zero-mapped memory areas etc..
89
+
*/
90
+
extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
91
+
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
92
+
93
+
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
94
+
extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
95
+
96
+
/*
97
+
* (pmds are folded into puds so this doesn't get actually called,
98
+
* but the define is needed for a generic inline function.)
99
+
*/
100
+
static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval)
101
+
{
102
+
pmdptr->pud.pgd.pgd = pmdval.pud.pgd.pgd;
103
+
}
104
+
105
+
/* to find an entry in a page-table-directory */
106
+
#define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
107
+
#define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
108
+
109
+
static inline int pte_write(pte_t pte) \
110
+
{ return pte_val(pte) & _PAGE_WRITE; }
111
+
static inline int pte_dirty(pte_t pte) \
112
+
{ return pte_val(pte) & _PAGE_DIRTY; }
113
+
static inline int pte_young(pte_t pte) \
114
+
{ return pte_val(pte) & _PAGE_ACCESSED; }
115
+
static inline int pte_file(pte_t pte) \
116
+
{ return pte_val(pte) & _PAGE_FILE; }
117
+
static inline int pte_special(pte_t pte) { return 0; }
118
+
119
+
#define pgprot_noncached pgprot_noncached
120
+
121
+
static inline pgprot_t pgprot_noncached(pgprot_t _prot)
122
+
{
123
+
unsigned long prot = pgprot_val(_prot);
124
+
125
+
prot &= ~_PAGE_CACHED;
126
+
127
+
return __pgprot(prot);
128
+
}
129
+
130
+
static inline int pte_none(pte_t pte)
131
+
{
132
+
return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf));
133
+
}
134
+
135
+
static inline int pte_present(pte_t pte) \
136
+
{ return pte_val(pte) & _PAGE_PRESENT; }
137
+
138
+
/*
139
+
* The following only work if pte_present() is true.
140
+
* Undefined behaviour if not..
141
+
*/
142
+
static inline pte_t pte_wrprotect(pte_t pte)
143
+
{
144
+
pte_val(pte) &= ~_PAGE_WRITE;
145
+
return pte;
146
+
}
147
+
148
+
static inline pte_t pte_mkclean(pte_t pte)
149
+
{
150
+
pte_val(pte) &= ~_PAGE_DIRTY;
151
+
return pte;
152
+
}
153
+
154
+
static inline pte_t pte_mkold(pte_t pte)
155
+
{
156
+
pte_val(pte) &= ~_PAGE_ACCESSED;
157
+
return pte;
158
+
}
159
+
160
+
static inline pte_t pte_mkwrite(pte_t pte)
161
+
{
162
+
pte_val(pte) |= _PAGE_WRITE;
163
+
return pte;
164
+
}
165
+
166
+
static inline pte_t pte_mkdirty(pte_t pte)
167
+
{
168
+
pte_val(pte) |= _PAGE_DIRTY;
169
+
return pte;
170
+
}
171
+
172
+
static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
173
+
174
+
static inline pte_t pte_mkyoung(pte_t pte)
175
+
{
176
+
pte_val(pte) |= _PAGE_ACCESSED;
177
+
return pte;
178
+
}
179
+
180
+
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
181
+
{
182
+
const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC;
183
+
184
+
pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
185
+
return pte;
186
+
}
187
+
188
+
static inline int pmd_present(pmd_t pmd)
189
+
{
190
+
return (pmd_val(pmd) != (unsigned long) invalid_pte_table)
191
+
&& (pmd_val(pmd) != 0UL);
192
+
}
193
+
194
+
static inline void pmd_clear(pmd_t *pmdp)
195
+
{
196
+
pmd_val(*pmdp) = (unsigned long) invalid_pte_table;
197
+
}
198
+
199
+
#define pte_pfn(pte) (pte_val(pte) & 0xfffff)
200
+
#define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot)))
201
+
#define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
202
+
203
+
/*
204
+
* Store a linux PTE into the linux page table.
205
+
*/
206
+
static inline void set_pte(pte_t *ptep, pte_t pteval)
207
+
{
208
+
*ptep = pteval;
209
+
}
210
+
211
+
static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
212
+
pte_t *ptep, pte_t pteval)
213
+
{
214
+
unsigned long paddr = page_to_virt(pte_page(pteval));
215
+
216
+
flush_dcache_range(paddr, paddr + PAGE_SIZE);
217
+
set_pte(ptep, pteval);
218
+
}
219
+
220
+
static inline int pmd_none(pmd_t pmd)
221
+
{
222
+
return (pmd_val(pmd) ==
223
+
(unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL);
224
+
}
225
+
226
+
#define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK)
227
+
228
+
static inline void pte_clear(struct mm_struct *mm,
229
+
unsigned long addr, pte_t *ptep)
230
+
{
231
+
pte_t null;
232
+
233
+
pte_val(null) = (addr >> PAGE_SHIFT) & 0xf;
234
+
235
+
set_pte_at(mm, addr, ptep, null);
236
+
flush_tlb_one(addr);
237
+
}
238
+
239
+
/*
240
+
* Conversion functions: convert a page and protection to a page entry,
241
+
* and a page entry and page directory to the page they refer to.
242
+
*/
243
+
#define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot))
244
+
245
+
#define pte_unmap(pte) do { } while (0)
246
+
247
+
/*
248
+
* Conversion functions: convert a page and protection to a page entry,
249
+
* and a page entry and page directory to the page they refer to.
250
+
*/
251
+
#define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd))
252
+
#define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
253
+
#define pmd_page_vaddr(pmd) pmd_val(pmd)
254
+
255
+
#define pte_offset_map(dir, addr) \
256
+
((pte_t *) page_address(pmd_page(*dir)) + \
257
+
(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
258
+
259
+
/* to find an entry in a kernel page-table-directory */
260
+
#define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
261
+
262
+
/* Get the address to the PTE for a vaddr in specific directory */
263
+
#define pte_offset_kernel(dir, addr) \
264
+
((pte_t *) pmd_page_vaddr(*(dir)) + \
265
+
(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
266
+
267
+
#define pte_ERROR(e) \
268
+
pr_err("%s:%d: bad pte %08lx.\n", \
269
+
__FILE__, __LINE__, pte_val(e))
270
+
#define pgd_ERROR(e) \
271
+
pr_err("%s:%d: bad pgd %08lx.\n", \
272
+
__FILE__, __LINE__, pgd_val(e))
273
+
274
+
/*
275
+
* Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte)
276
+
* && !pte_file(pte)):
277
+
*
278
+
* 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ... 1 0
279
+
* 0 0 0 0 type. 0 0 0 0 0 0 offset.........
280
+
*
281
+
* This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file.
282
+
*
283
+
* Note that the offset field is always non-zero, thus !pte_none(pte) is always
284
+
* true.
285
+
*/
286
+
#define __swp_type(swp) (((swp).val >> 26) & 0x3)
287
+
#define __swp_offset(swp) ((swp).val & 0xfffff)
288
+
#define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x3) << 26) \
289
+
| ((off) & 0xfffff) })
290
+
#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
291
+
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
292
+
293
+
/* Encode and decode a nonlinear file mapping entry */
294
+
#define PTE_FILE_MAX_BITS 25
295
+
#define pte_to_pgoff(pte) (pte_val(pte) & 0x1ffffff)
296
+
#define pgoff_to_pte(off) __pte(((off) & 0x1ffffff) | _PAGE_FILE)
297
+
298
+
#define kern_addr_valid(addr) (1)
299
+
300
+
#include <asm-generic/pgtable.h>
301
+
302
+
#define pgtable_cache_init() do { } while (0)
303
+
304
+
extern void __init paging_init(void);
305
+
extern void __init mmu_init(void);
306
+
307
+
extern void update_mmu_cache(struct vm_area_struct *vma,
308
+
unsigned long address, pte_t *pte);
309
+
310
+
#endif /* _ASM_NIOS2_PGTABLE_H */
+74
arch/nios2/mm/pgtable.c
+74
arch/nios2/mm/pgtable.c
···
1
+
/*
2
+
* Copyright (C) 2009 Wind River Systems Inc
3
+
* Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
4
+
*
5
+
* This file is subject to the terms and conditions of the GNU General Public
6
+
* License. See the file "COPYING" in the main directory of this archive
7
+
* for more details.
8
+
*/
9
+
10
+
#include <linux/mm.h>
11
+
#include <linux/sched.h>
12
+
13
+
#include <asm/pgtable.h>
14
+
#include <asm/cpuinfo.h>
15
+
16
+
/* pteaddr:
17
+
* ptbase | vpn* | zero
18
+
* 31-22 | 21-2 | 1-0
19
+
*
20
+
* *vpn is preserved on double fault
21
+
*
22
+
* tlbacc:
23
+
* IG |*flags| pfn
24
+
* 31-25|24-20 | 19-0
25
+
*
26
+
* *crwxg
27
+
*
28
+
* tlbmisc:
29
+
* resv |way |rd | we|pid |dbl|bad|perm|d
30
+
* 31-24 |23-20 |19 | 20|17-4|3 |2 |1 |0
31
+
*
32
+
*/
33
+
34
+
/*
35
+
* Initialize a new pgd / pmd table with invalid pointers.
36
+
*/
37
+
static void pgd_init(pgd_t *pgd)
38
+
{
39
+
unsigned long *p = (unsigned long *) pgd;
40
+
int i;
41
+
42
+
for (i = 0; i < USER_PTRS_PER_PGD; i += 8) {
43
+
p[i + 0] = (unsigned long) invalid_pte_table;
44
+
p[i + 1] = (unsigned long) invalid_pte_table;
45
+
p[i + 2] = (unsigned long) invalid_pte_table;
46
+
p[i + 3] = (unsigned long) invalid_pte_table;
47
+
p[i + 4] = (unsigned long) invalid_pte_table;
48
+
p[i + 5] = (unsigned long) invalid_pte_table;
49
+
p[i + 6] = (unsigned long) invalid_pte_table;
50
+
p[i + 7] = (unsigned long) invalid_pte_table;
51
+
}
52
+
}
53
+
54
+
pgd_t *pgd_alloc(struct mm_struct *mm)
55
+
{
56
+
pgd_t *ret, *init;
57
+
58
+
ret = (pgd_t *) __get_free_pages(GFP_KERNEL, PGD_ORDER);
59
+
if (ret) {
60
+
init = pgd_offset(&init_mm, 0UL);
61
+
pgd_init(ret);
62
+
memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
63
+
(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
64
+
}
65
+
66
+
return ret;
67
+
}
68
+
69
+
void __init pagetable_init(void)
70
+
{
71
+
/* Initialize the entire pgd. */
72
+
pgd_init(swapper_pg_dir);
73
+
pgd_init(swapper_pg_dir + USER_PTRS_PER_PGD);
74
+
}