[ARM] dma: provide a better dma_map_page() implementation
We can translate a struct page directly to a DMA address using
page_to_dma(). No need to use page_address() followed by
virt_to_dma().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index eff9548..856ee1b 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -227,13 +227,22 @@
* can regain ownership by calling dma_unmap_page() or
* dma_sync_single_for_cpu().
*/
+#ifndef CONFIG_DMABOUNCE
static inline dma_addr_t
dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir)
{
- return dma_map_single(dev, page_address(page) + offset, size, dir);
+ if (!arch_is_coherent())
+ dma_cache_maint(page_address(page) + offset, size, dir);
+
+ return page_to_dma(dev, page) + offset;
}
+#else
+extern dma_addr_t dma_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir);
+#endif
/**
* dma_unmap_single - unmap a single buffer previously mapped