aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-generic/pgtable.h
blob: 358e4d309ceb179776f2a7036dabce02cdfad1d2 (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
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
#ifndef _ASM_GENERIC_PGTABLE_H
#define _ASM_GENERIC_PGTABLE_H

#ifndef __HAVE_ARCH_PTEP_ESTABLISH
/*
 * Establish a new mapping:
 *  - flush the old one
 *  - update the page tables
 *  - inform the TLB about the new one
 *
 * We hold the mm semaphore for reading, and the pte lock.
 *
 * Note: the old pte is known to not be writable, so we don't need to
 * worry about dirty bits etc getting lost.
 */
#ifndef __HAVE_ARCH_SET_PTE_ATOMIC
#define ptep_establish(__vma, __address, __ptep, __entry)		\
do {				  					\
	set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry);	\
	flush_tlb_page(__vma, __address);				\
} while (0)
#else /* __HAVE_ARCH_SET_PTE_ATOMIC */
#define ptep_establish(__vma, __address, __ptep, __entry)		\
do {				  					\
	set_pte_atomic(__ptep, __entry);				\
	flush_tlb_page(__vma, __address);				\
} while (0)
#endif /* __HAVE_ARCH_SET_PTE_ATOMIC */
#endif

#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
/*
 * Largely same as above, but only sets the access flags (dirty,
 * accessed, and writable). Furthermore, we know it always gets set
 * to a "more permissive" setting, which allows most architectures
 * to optimize this.
 */
#define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
do {				  					  \
	set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry);	  \
	flush_tlb_page(__vma, __address);				  \
} while (0)
#endif

#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define ptep_test_and_clear_young(__vma, __address, __ptep)		\
({									\
	pte_t __pte = *(__ptep);					\
	int r = 1;							\
	if (!pte_young(__pte))						\
		r = 0;							\
	else								\
		set_pte_at((__vma)->vm_mm, (__address),			\
			   (__ptep), pte_mkold(__pte));			\
	r;								\
})
#endif

#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
#define ptep_clear_flush_young(__vma, __address, __ptep)		\
({									\
	int __young;							\
	__young = ptep_test_and_clear_young(__vma, __address, __ptep);	\
	if (__young)							\
		flush_tlb_page(__vma, __address);			\
	__young;							\
})
#endif

#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
#define ptep_test_and_clear_dirty(__vma, __address, __ptep)		\
({									\
	pte_t __pte = *__ptep;						\
	int r = 1;							\
	if (!pte_dirty(__pte))						\
		r = 0;							\
	else								\
		set_pte_at((__vma)->vm_mm, (__address), (__ptep),	\
			   pte_mkclean(__pte));				\
	r;								\
})
#endif

#ifndef __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH
#define ptep_clear_flush_dirty(__vma, __address, __ptep)		\
({									\
	int __dirty;							\
	__dirty = ptep_test_and_clear_dirty(__vma, __address, __ptep);	\
	if (__dirty)							\
		flush_tlb_page(__vma, __address);			\
	__dirty;							\
})
#endif

#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define ptep_get_and_clear(__mm, __address, __ptep)			\
({									\
	pte_t __pte = *(__ptep);					\
	pte_clear((__mm), (__address), (__ptep));			\
	__pte;								\
})
#endif

#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
#define ptep_get_and_clear_full(__mm, __address, __ptep, __full)	\
({									\
	pte_t __pte;							\
	__pte = ptep_get_and_clear((__mm), (__address), (__ptep));	\
	__pte;								\
})
#endif

#ifndef __HAVE_ARCH_PTE_CLEAR_FULL
#define pte_clear_full(__mm, __address, __ptep, __full)			\
do {									\
	pte_clear((__mm), (__address), (__ptep));			\
} while (0)
#endif

#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
#define ptep_clear_flush(__vma, __address, __ptep)			\
({									\
	pte_t __pte;							\
	__pte = ptep_get_and_clear((__vma)->vm_mm, __address, __ptep);	\
	flush_tlb_page(__vma, __address);				\
	__pte;								\
})
#endif

#ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
struct mm_struct;
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
{
	pte_t old_pte = *ptep;
	set_pte_at(mm, address, ptep, pte_wrprotect(old_pte));
}
#endif

#ifndef __HAVE_ARCH_PTE_SAME
#define pte_same(A,B)	(pte_val(A) == pte_val(B))
#endif

#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY
#define page_test_and_clear_dirty(page) (0)
#define pte_maybe_dirty(pte)		pte_dirty(pte)
#else
#define pte_maybe_dirty(pte)		(1)
#endif

#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG
#define page_test_and_clear_young(page) (0)
#endif

#ifndef __HAVE_ARCH_PGD_OFFSET_GATE
#define pgd_offset_gate(mm, addr)	pgd_offset(mm, addr)
#endif

#ifndef __HAVE_ARCH_LAZY_MMU_PROT_UPDATE
#define lazy_mmu_prot_update(pte)	do { } while (0)
#endif

#ifndef __HAVE_ARCH_MULTIPLE_ZERO_PAGE
#define move_pte(pte, prot, old_addr, new_addr)	(pte)
#else
#define move_pte(pte, prot, old_addr, new_addr)				\
({									\
 	pte_t newpte = (pte);						\
	if (pte_present(pte) && pfn_valid(pte_pfn(pte)) &&		\
			pte_page(pte) == ZERO_PAGE(old_addr))		\
		newpte = mk_pte(ZERO_PAGE(new_addr), (prot));		\
	newpte;								\
})
#endif

/*
 * When walking page tables, get the address of the next boundary,
 * or the end address of the range if that comes earlier.  Although no
 * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
 */

#define pgd_addr_end(addr, end)						\
({	unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK;	\
	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
})

#ifndef pud_addr_end
#define pud_addr_end(addr, end)						\
({	unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK;	\
	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
})
#endif

#ifndef pmd_addr_end
#define pmd_addr_end(addr, end)						\
({	unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK;	\
	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
})
#endif

#ifndef __ASSEMBLY__
/*
 * When walking page tables, we usually want to skip any p?d_none entries;
 * and any p?d_bad entries - reporting the error before resetting to none.
 * Do the tests inline, but report and clear the bad entry in mm/memory.c.
 */
void pgd_clear_bad(pgd_t *);
void pud_clear_bad(pud_t *);
void pmd_clear_bad(pmd_t *);

static inline int pgd_none_or_clear_bad(pgd_t *pgd)
{
	if (pgd_none(*pgd))
		return 1;
	if (unlikely(pgd_bad(*pgd))) {
		pgd_clear_bad(pgd);
		return 1;
	}
	return 0;
}

static inline int pud_none_or_clear_bad(pud_t *pud)
{
	if (pud_none(*pud))
		return 1;
	if (unlikely(pud_bad(*pud))) {
		pud_clear_bad(pud);
		return 1;
	}
	return 0;
}

static inline int pmd_none_or_clear_bad(pmd_t *pmd)
{
	if (pmd_none(*pmd))
		return 1;
	if (unlikely(pmd_bad(*pmd))) {
		pmd_clear_bad(pmd);
		return 1;
	}
	return 0;
}
#endif /* !__ASSEMBLY__ */

#endif /* _ASM_GENERIC_PGTABLE_H */