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1#ifndef _ASM_X86_CACHEFLUSH_H
2#define _ASM_X86_CACHEFLUSH_H
3
4/* Keep includes the same across arches. */
5#include <linux/mm.h>
6
7/* Caches aren't brain-dead on the intel. */
8static inline void flush_cache_all(void) { }
9static inline void flush_cache_mm(struct mm_struct *mm) { }
10static inline void flush_cache_dup_mm(struct mm_struct *mm) { }
11static inline void flush_cache_range(struct vm_area_struct *vma,
12 unsigned long start, unsigned long end) { }
13static inline void flush_cache_page(struct vm_area_struct *vma,
14 unsigned long vmaddr, unsigned long pfn) { }
15#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
16static inline void flush_dcache_page(struct page *page) { }
17static inline void flush_dcache_mmap_lock(struct address_space *mapping) { }
18static inline void flush_dcache_mmap_unlock(struct address_space *mapping) { }
19static inline void flush_icache_range(unsigned long start,
20 unsigned long end) { }
21static inline void flush_icache_page(struct vm_area_struct *vma,
22 struct page *page) { }
23static inline void flush_icache_user_range(struct vm_area_struct *vma,
24 struct page *page,
25 unsigned long addr,
26 unsigned long len) { }
27static inline void flush_cache_vmap(unsigned long start, unsigned long end) { }
28static inline void flush_cache_vunmap(unsigned long start,
29 unsigned long end) { }
30
31static inline void copy_to_user_page(struct vm_area_struct *vma,
32 struct page *page, unsigned long vaddr,
33 void *dst, const void *src,
34 unsigned long len)
35{
36 memcpy(dst, src, len);
37}
38
39static inline void copy_from_user_page(struct vm_area_struct *vma,
40 struct page *page, unsigned long vaddr,
41 void *dst, const void *src,
42 unsigned long len)
43{
44 memcpy(dst, src, len);
45}
46
47#ifdef CONFIG_X86_PAT
48/*
49 * X86 PAT uses page flags WC and Uncached together to keep track of
50 * memory type of pages that have backing page struct. X86 PAT supports 3
51 * different memory types, _PAGE_CACHE_WB, _PAGE_CACHE_WC and
52 * _PAGE_CACHE_UC_MINUS and fourth state where page's memory type has not
53 * been changed from its default (value of -1 used to denote this).
54 * Note we do not support _PAGE_CACHE_UC here.
55 */
56
57#define _PGMT_DEFAULT 0
58#define _PGMT_WC (1UL << PG_arch_1)
59#define _PGMT_UC_MINUS (1UL << PG_uncached)
60#define _PGMT_WB (1UL << PG_uncached | 1UL << PG_arch_1)
61#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1)
62#define _PGMT_CLEAR_MASK (~_PGMT_MASK)
63
64static inline unsigned long get_page_memtype(struct page *pg)
65{
66 unsigned long pg_flags = pg->flags & _PGMT_MASK;
67
68 if (pg_flags == _PGMT_DEFAULT)
69 return -1;
70 else if (pg_flags == _PGMT_WC)
71 return _PAGE_CACHE_WC;
72 else if (pg_flags == _PGMT_UC_MINUS)
73 return _PAGE_CACHE_UC_MINUS;
74 else
75 return _PAGE_CACHE_WB;
76}
77
78static inline void set_page_memtype(struct page *pg, unsigned long memtype)
79{
80 unsigned long memtype_flags = _PGMT_DEFAULT;
81 unsigned long old_flags;
82 unsigned long new_flags;
83
84 switch (memtype) {
85 case _PAGE_CACHE_WC:
86 memtype_flags = _PGMT_WC;
87 break;
88 case _PAGE_CACHE_UC_MINUS:
89 memtype_flags = _PGMT_UC_MINUS;
90 break;
91 case _PAGE_CACHE_WB:
92 memtype_flags = _PGMT_WB;
93 break;
94 }
95
96 do {
97 old_flags = pg->flags;
98 new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
99 } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
100}
101#else
102static inline unsigned long get_page_memtype(struct page *pg) { return -1; }
103static inline void set_page_memtype(struct page *pg, unsigned long memtype) { }
104#endif
105
106/*
107 * The set_memory_* API can be used to change various attributes of a virtual
108 * address range. The attributes include:
109 * Cachability : UnCached, WriteCombining, WriteBack
110 * Executability : eXeutable, NoteXecutable
111 * Read/Write : ReadOnly, ReadWrite
112 * Presence : NotPresent
113 *
114 * Within a catagory, the attributes are mutually exclusive.
115 *
116 * The implementation of this API will take care of various aspects that
117 * are associated with changing such attributes, such as:
118 * - Flushing TLBs
119 * - Flushing CPU caches
120 * - Making sure aliases of the memory behind the mapping don't violate
121 * coherency rules as defined by the CPU in the system.
122 *
123 * What this API does not do:
124 * - Provide exclusion between various callers - including callers that
125 * operation on other mappings of the same physical page
126 * - Restore default attributes when a page is freed
127 * - Guarantee that mappings other than the requested one are
128 * in any state, other than that these do not violate rules for
129 * the CPU you have. Do not depend on any effects on other mappings,
130 * CPUs other than the one you have may have more relaxed rules.
131 * The caller is required to take care of these.
132 */
133
134int _set_memory_uc(unsigned long addr, int numpages);
135int _set_memory_wc(unsigned long addr, int numpages);
136int _set_memory_wb(unsigned long addr, int numpages);
137int set_memory_uc(unsigned long addr, int numpages);
138int set_memory_wc(unsigned long addr, int numpages);
139int set_memory_wb(unsigned long addr, int numpages);
140int set_memory_x(unsigned long addr, int numpages);
141int set_memory_nx(unsigned long addr, int numpages);
142int set_memory_ro(unsigned long addr, int numpages);
143int set_memory_rw(unsigned long addr, int numpages);
144int set_memory_np(unsigned long addr, int numpages);
145int set_memory_4k(unsigned long addr, int numpages);
146
147int set_memory_array_uc(unsigned long *addr, int addrinarray);
148int set_memory_array_wc(unsigned long *addr, int addrinarray);
149int set_memory_array_wb(unsigned long *addr, int addrinarray);
150
151int set_pages_array_uc(struct page **pages, int addrinarray);
152int set_pages_array_wc(struct page **pages, int addrinarray);
153int set_pages_array_wb(struct page **pages, int addrinarray);
154
155/*
156 * For legacy compatibility with the old APIs, a few functions
157 * are provided that work on a "struct page".
158 * These functions operate ONLY on the 1:1 kernel mapping of the
159 * memory that the struct page represents, and internally just
160 * call the set_memory_* function. See the description of the
161 * set_memory_* function for more details on conventions.
162 *
163 * These APIs should be considered *deprecated* and are likely going to
164 * be removed in the future.
165 * The reason for this is the implicit operation on the 1:1 mapping only,
166 * making this not a generally useful API.
167 *
168 * Specifically, many users of the old APIs had a virtual address,
169 * called virt_to_page() or vmalloc_to_page() on that address to
170 * get a struct page* that the old API required.
171 * To convert these cases, use set_memory_*() on the original
172 * virtual address, do not use these functions.
173 */
174
175int set_pages_uc(struct page *page, int numpages);
176int set_pages_wb(struct page *page, int numpages);
177int set_pages_x(struct page *page, int numpages);
178int set_pages_nx(struct page *page, int numpages);
179int set_pages_ro(struct page *page, int numpages);
180int set_pages_rw(struct page *page, int numpages);
181
182
183void clflush_cache_range(void *addr, unsigned int size);
184
185#ifdef CONFIG_DEBUG_RODATA
186void mark_rodata_ro(void);
187extern const int rodata_test_data;
188extern int kernel_set_to_readonly;
189void set_kernel_text_rw(void);
190void set_kernel_text_ro(void);
191#else
192static inline void set_kernel_text_rw(void) { }
193static inline void set_kernel_text_ro(void) { }
194#endif
195
196#ifdef CONFIG_DEBUG_RODATA_TEST
197int rodata_test(void);
198#else
199static inline int rodata_test(void)
200{
201 return 0;
202}
203#endif
204
205#endif /* _ASM_X86_CACHEFLUSH_H */