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