x86, swiotlb: add map_page and unmap_page

This is a preparation of struct dma_mapping_ops unification. We use
map_page and unmap_page instead of map_single and unmap_single.

This is sorta temporary workaround. We will move them to lib/swiotlb.c
to enable x86's swiotlb code to directly use them.

We will remove map_single and unmap_single hooks in the last patch in
this patchset.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/pci-swiotlb_64.c b/arch/x86/kernel/pci-swiotlb_64.c
index d59c917..d1c0366 100644 (file)
--- a/arch/x86/kernel/pci-swiotlb_64.c
+++ b/arch/x86/kernel/pci-swiotlb_64.c
@@ -45,6 +45,23 @@ swiotlb_map_single_phys(struct device *hwdev, phys_addr_t paddr, size_t size,
        return swiotlb_map_single(hwdev, phys_to_virt(paddr), size, direction);
 }
 
+/* these will be moved to lib/swiotlb.c later on */
+
+static dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
+                                  unsigned long offset, size_t size,
+                                  enum dma_data_direction dir,
+                                  struct dma_attrs *attrs)
+{
+       return swiotlb_map_single(dev, page_address(page) + offset, size, dir);
+}
+
+static void swiotlb_unmap_page(struct device *dev, dma_addr_t dma_handle,
+                              size_t size, enum dma_data_direction dir,
+                              struct dma_attrs *attrs)
+{
+       swiotlb_unmap_single(dev, dma_handle, size, dir);
+}
+
 static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
                                        dma_addr_t *dma_handle, gfp_t flags)
 {
@@ -71,6 +88,8 @@ struct dma_mapping_ops swiotlb_dma_ops = {
        .sync_sg_for_device = swiotlb_sync_sg_for_device,
        .map_sg = swiotlb_map_sg,
        .unmap_sg = swiotlb_unmap_sg,
+       .map_page = swiotlb_map_page,
+       .unmap_page = swiotlb_unmap_page,
        .dma_supported = NULL,
 };