arch/x86/include/asm/cacheflush.h

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