Merge branch 'stable-3.2' into pandora-3.2

[pandora-kernel.git] / arch / arm / mm / flush.c

diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index b10e47a..ac5416a 100644 (file)
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -296,7 +296,7 @@ void flush_dcache_page(struct page *page)
        mapping = page_mapping(page);
 
        if (!cache_ops_need_broadcast() &&
-           mapping && !mapping_mapped(mapping))
+           mapping && !page_mapped(page))
                clear_bit(PG_dcache_clean, &page->flags);
        else {
                __flush_dcache_page(mapping, page);
@@ -309,6 +309,39 @@ void flush_dcache_page(struct page *page)
 }
 EXPORT_SYMBOL(flush_dcache_page);
 
+/*
+ * Ensure cache coherency for the kernel mapping of this page. We can
+ * assume that the page is pinned via kmap.
+ *
+ * If the page only exists in the page cache and there are no user
+ * space mappings, this is a no-op since the page was already marked
+ * dirty at creation.  Otherwise, we need to flush the dirty kernel
+ * cache lines directly.
+ */
+void flush_kernel_dcache_page(struct page *page)
+{
+       if (cache_is_vivt() || cache_is_vipt_aliasing()) {
+               struct address_space *mapping;
+
+               mapping = page_mapping(page);
+
+               if (!mapping || mapping_mapped(mapping)) {
+                       void *addr;
+
+                       addr = page_address(page);
+                       /*
+                        * kmap_atomic() doesn't set the page virtual
+                        * address for highmem pages, and
+                        * kunmap_atomic() takes care of cache
+                        * flushing already.
+                        */
+                       if (!IS_ENABLED(CONFIG_HIGHMEM) || addr)
+                               __cpuc_flush_dcache_area(addr, PAGE_SIZE);
+               }
+       }
+}
+EXPORT_SYMBOL(flush_kernel_dcache_page);
+
 /*
  * Flush an anonymous page so that users of get_user_pages()
  * can safely access the data.  The expected sequence is: