diff options
| -rw-r--r-- | arch/arm/mm/flush.c | 39 | ||||
| -rw-r--r-- | include/asm-arm/cacheflush.h | 10 |
2 files changed, 49 insertions, 0 deletions
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c index 628348c9f6c5..9df507d36e0b 100644 --- a/arch/arm/mm/flush.c +++ b/arch/arm/mm/flush.c @@ -202,3 +202,42 @@ void flush_dcache_page(struct page *page) } } EXPORT_SYMBOL(flush_dcache_page); + +/* + * Flush an anonymous page so that users of get_user_pages() + * can safely access the data. The expected sequence is: + * + * get_user_pages() + * -> flush_anon_page + * memcpy() to/from page + * if written to page, flush_dcache_page() + */ +void __flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr) +{ + unsigned long pfn; + + /* VIPT non-aliasing caches need do nothing */ + if (cache_is_vipt_nonaliasing()) + return; + + /* + * Write back and invalidate userspace mapping. + */ + pfn = page_to_pfn(page); + if (cache_is_vivt()) { + flush_cache_page(vma, vmaddr, pfn); + } else { + /* + * For aliasing VIPT, we can flush an alias of the + * userspace address only. + */ + flush_pfn_alias(pfn, vmaddr); + } + + /* + * Invalidate kernel mapping. No data should be contained + * in this mapping of the page. FIXME: this is overkill + * since we actually ask for a write-back and invalidate. + */ + __cpuc_flush_dcache_page(page_address(page)); +} diff --git a/include/asm-arm/cacheflush.h b/include/asm-arm/cacheflush.h index d51049522cd0..5f531ea03059 100644 --- a/include/asm-arm/cacheflush.h +++ b/include/asm-arm/cacheflush.h @@ -357,6 +357,16 @@ extern void flush_dcache_page(struct page *); extern void __flush_dcache_page(struct address_space *mapping, struct page *page); +#define ARCH_HAS_FLUSH_ANON_PAGE +static inline void flush_anon_page(struct vm_area_struct *vma, + struct page *page, unsigned long vmaddr) +{ + extern void __flush_anon_page(struct vm_area_struct *vma, + struct page *, unsigned long); + if (PageAnon(page)) + __flush_anon_page(vma, page, vmaddr); +} + #define flush_dcache_mmap_lock(mapping) \ write_lock_irq(&(mapping)->tree_lock) #define flush_dcache_mmap_unlock(mapping) \ |