diff options
Diffstat (limited to 'include/asm-x86/cacheflush.h')
| -rw-r--r-- | include/asm-x86/cacheflush.h | 63 |
1 files changed, 55 insertions, 8 deletions
diff --git a/include/asm-x86/cacheflush.h b/include/asm-x86/cacheflush.h index cb1d6f8fd00..f4c0ab50d2c 100644 --- a/include/asm-x86/cacheflush.h +++ b/include/asm-x86/cacheflush.h @@ -24,15 +24,34 @@ #define copy_from_user_page(vma, page, vaddr, dst, src, len) \ memcpy((dst), (src), (len)) -int __deprecated_for_modules change_page_attr(struct page *page, int numpages, - pgprot_t prot); -int set_pages_uc(struct page *page, int numpages); -int set_pages_wb(struct page *page, int numpages); -int set_pages_x(struct page *page, int numpages); -int set_pages_nx(struct page *page, int numpages); -int set_pages_ro(struct page *page, int numpages); -int set_pages_rw(struct page *page, int numpages); +/* + * The set_memory_* API can be used to change various attributes of a virtual + * address range. The attributes include: + * Cachability : UnCached, WriteCombining, WriteBack + * Executability : eXeutable, NoteXecutable + * Read/Write : ReadOnly, ReadWrite + * Presence : NotPresent + * + * Within a catagory, the attributes are mutually exclusive. + * + * The implementation of this API will take care of various aspects that + * are associated with changing such attributes, such as: + * - Flushing TLBs + * - Flushing CPU caches + * - Making sure aliases of the memory behind the mapping don't violate + * coherency rules as defined by the CPU in the system. + * + * What this API does not do: + * - Provide exclusion between various callers - including callers that + * operation on other mappings of the same physical page + * - Restore default attributes when a page is freed + * - Guarantee that mappings other than the requested one are + * in any state, other than that these do not violate rules for + * the CPU you have. Do not depend on any effects on other mappings, + * CPUs other than the one you have may have more relaxed rules. + * The caller is required to take care of these. + */ int _set_memory_uc(unsigned long addr, int numpages); int _set_memory_wc(unsigned long addr, int numpages); @@ -47,6 +66,34 @@ int set_memory_rw(unsigned long addr, int numpages); int set_memory_np(unsigned long addr, int numpages); int set_memory_4k(unsigned long addr, int numpages); +/* + * For legacy compatibility with the old APIs, a few functions + * are provided that work on a "struct page". + * These functions operate ONLY on the 1:1 kernel mapping of the + * memory that the struct page represents, and internally just + * call the set_memory_* function. See the description of the + * set_memory_* function for more details on conventions. + * + * These APIs should be considered *deprecated* and are likely going to + * be removed in the future. + * The reason for this is the implicit operation on the 1:1 mapping only, + * making this not a generally useful API. + * + * Specifically, many users of the old APIs had a virtual address, + * called virt_to_page() or vmalloc_to_page() on that address to + * get a struct page* that the old API required. + * To convert these cases, use set_memory_*() on the original + * virtual address, do not use these functions. + */ + +int set_pages_uc(struct page *page, int numpages); +int set_pages_wb(struct page *page, int numpages); +int set_pages_x(struct page *page, int numpages); +int set_pages_nx(struct page *page, int numpages); +int set_pages_ro(struct page *page, int numpages); +int set_pages_rw(struct page *page, int numpages); + + void clflush_cache_range(void *addr, unsigned int size); void cpa_init(void); |