diff options
Diffstat (limited to 'arch/arm/mm/flush.c')
| -rw-r--r-- | arch/arm/mm/flush.c | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c index 454205b789d..9df507d36e0 100644 --- a/arch/arm/mm/flush.c +++ b/arch/arm/mm/flush.c @@ -26,7 +26,7 @@ static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr) unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT); const int zero = 0; - set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL)); + set_pte_ext(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL), 0); flush_tlb_kernel_page(to); asm( "mcrr p15, 0, %1, %0, c14\n" @@ -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)); +} |