1#ifndef _ASM_GENERIC_PGTABLE_H
2#define _ASM_GENERIC_PGTABLE_H
3
4#ifndef __HAVE_ARCH_PTEP_ESTABLISH
5/*
6 * Establish a new mapping:
7 *  - flush the old one
8 *  - update the page tables
9 *  - inform the TLB about the new one
10 *
11 * We hold the mm semaphore for reading, and the pte lock.
12 *
13 * Note: the old pte is known to not be writable, so we don't need to
14 * worry about dirty bits etc getting lost.
15 */
16#ifndef __HAVE_ARCH_SET_PTE_ATOMIC
17#define ptep_establish(__vma, __address, __ptep, __entry)		\
18do {				  					\
19	set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry);	\
20	flush_tlb_page(__vma, __address);				\
21} while (0)
22#else /* __HAVE_ARCH_SET_PTE_ATOMIC */
23#define ptep_establish(__vma, __address, __ptep, __entry)		\
24do {				  					\
25	set_pte_atomic(__ptep, __entry);				\
26	flush_tlb_page(__vma, __address);				\
27} while (0)
28#endif /* __HAVE_ARCH_SET_PTE_ATOMIC */
29#endif
30
31#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
32/*
33 * Largely same as above, but only sets the access flags (dirty,
34 * accessed, and writable). Furthermore, we know it always gets set
35 * to a "more permissive" setting, which allows most architectures
36 * to optimize this.
37 */
38#define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
39do {				  					  \
40	set_pte_at((__vma)->vm_mm, (__address), __ptep, __entry);	  \
41	flush_tlb_page(__vma, __address);				  \
42} while (0)
43#endif
44
45#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
46#define ptep_test_and_clear_young(__vma, __address, __ptep)		\
47({									\
48	pte_t __pte = *(__ptep);					\
49	int r = 1;							\
50	if (!pte_young(__pte))						\
51		r = 0;							\
52	else								\
53		set_pte_at((__vma)->vm_mm, (__address),			\
54			   (__ptep), pte_mkold(__pte));			\
55	r;								\
56})
57#endif
58
59#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
60#define ptep_clear_flush_young(__vma, __address, __ptep)		\
61({									\
62	int __young;							\
63	__young = ptep_test_and_clear_young(__vma, __address, __ptep);	\
64	if (__young)							\
65		flush_tlb_page(__vma, __address);			\
66	__young;							\
67})
68#endif
69
70#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
71#define ptep_test_and_clear_dirty(__vma, __address, __ptep)		\
72({									\
73	pte_t __pte = *__ptep;						\
74	int r = 1;							\
75	if (!pte_dirty(__pte))						\
76		r = 0;							\
77	else								\
78		set_pte_at((__vma)->vm_mm, (__address), (__ptep),	\
79			   pte_mkclean(__pte));				\
80	r;								\
81})
82#endif
83
84#ifndef __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH
85#define ptep_clear_flush_dirty(__vma, __address, __ptep)		\
86({									\
87	int __dirty;							\
88	__dirty = ptep_test_and_clear_dirty(__vma, __address, __ptep);	\
89	if (__dirty)							\
90		flush_tlb_page(__vma, __address);			\
91	__dirty;							\
92})
93#endif
94
95#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
96#define ptep_get_and_clear(__mm, __address, __ptep)			\
97({									\
98	pte_t __pte = *(__ptep);					\
99	pte_clear((__mm), (__address), (__ptep));			\
100	__pte;								\
101})
102#endif
103
104#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
105#define ptep_get_and_clear_full(__mm, __address, __ptep, __full)	\
106({									\
107	pte_t __pte;							\
108	__pte = ptep_get_and_clear((__mm), (__address), (__ptep));	\
109	__pte;								\
110})
111#endif
112
113#ifndef __HAVE_ARCH_PTE_CLEAR_FULL
114#define pte_clear_full(__mm, __address, __ptep, __full)			\
115do {									\
116	pte_clear((__mm), (__address), (__ptep));			\
117} while (0)
118#endif
119
120#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
121#define ptep_clear_flush(__vma, __address, __ptep)			\
122({									\
123	pte_t __pte;							\
124	__pte = ptep_get_and_clear((__vma)->vm_mm, __address, __ptep);	\
125	flush_tlb_page(__vma, __address);				\
126	__pte;								\
127})
128#endif
129
130#ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
131struct mm_struct;
132static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
133{
134	pte_t old_pte = *ptep;
135	set_pte_at(mm, address, ptep, pte_wrprotect(old_pte));
136}
137#endif
138
139#ifndef __HAVE_ARCH_PTE_SAME
140#define pte_same(A,B)	(pte_val(A) == pte_val(B))
141#endif
142
143#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY
144#define page_test_and_clear_dirty(page) (0)
145#define pte_maybe_dirty(pte)		pte_dirty(pte)
146#else
147#define pte_maybe_dirty(pte)		(1)
148#endif
149
150#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG
151#define page_test_and_clear_young(page) (0)
152#endif
153
154#ifndef __HAVE_ARCH_PGD_OFFSET_GATE
155#define pgd_offset_gate(mm, addr)	pgd_offset(mm, addr)
156#endif
157
158#ifndef __HAVE_ARCH_LAZY_MMU_PROT_UPDATE
159#define lazy_mmu_prot_update(pte)	do { } while (0)
160#endif
161
162#ifndef __HAVE_ARCH_MOVE_PTE
163#define move_pte(pte, prot, old_addr, new_addr)	(pte)
164#endif
165
166/*
167 * When walking page tables, get the address of the next boundary,
168 * or the end address of the range if that comes earlier.  Although no
169 * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
170 */
171
172#define pgd_addr_end(addr, end)						\
173({	unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK;	\
174	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
175})
176
177#ifndef pud_addr_end
178#define pud_addr_end(addr, end)						\
179({	unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK;	\
180	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
181})
182#endif
183
184#ifndef pmd_addr_end
185#define pmd_addr_end(addr, end)						\
186({	unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK;	\
187	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
188})
189#endif
190
191#ifndef __ASSEMBLY__
192/*
193 * When walking page tables, we usually want to skip any p?d_none entries;
194 * and any p?d_bad entries - reporting the error before resetting to none.
195 * Do the tests inline, but report and clear the bad entry in mm/memory.c.
196 */
197void pgd_clear_bad(pgd_t *);
198void pud_clear_bad(pud_t *);
199void pmd_clear_bad(pmd_t *);
200
201static inline int pgd_none_or_clear_bad(pgd_t *pgd)
202{
203	if (pgd_none(*pgd))
204		return 1;
205	if (unlikely(pgd_bad(*pgd))) {
206		pgd_clear_bad(pgd);
207		return 1;
208	}
209	return 0;
210}
211
212static inline int pud_none_or_clear_bad(pud_t *pud)
213{
214	if (pud_none(*pud))
215		return 1;
216	if (unlikely(pud_bad(*pud))) {
217		pud_clear_bad(pud);
218		return 1;
219	}
220	return 0;
221}
222
223static inline int pmd_none_or_clear_bad(pmd_t *pmd)
224{
225	if (pmd_none(*pmd))
226		return 1;
227	if (unlikely(pmd_bad(*pmd))) {
228		pmd_clear_bad(pmd);
229		return 1;
230	}
231	return 0;
232}
233#endif /* !__ASSEMBLY__ */
234
235#endif /* _ASM_GENERIC_PGTABLE_H */
236