x86, gart: 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.

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-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 00c2bcd..e49c6dd 100644 (file)
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -255,10 +255,13 @@ static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
 }
 
 /* Map a single area into the IOMMU */
-static dma_addr_t
-gart_map_single(struct device *dev, phys_addr_t paddr, size_t size, int dir)
+static dma_addr_t gart_map_page(struct device *dev, struct page *page,
+                               unsigned long offset, size_t size,
+                               enum dma_data_direction dir,
+                               struct dma_attrs *attrs)
 {
        unsigned long bus;
+       phys_addr_t paddr = page_to_phys(page) + offset;
 
        if (!dev)
                dev = &x86_dma_fallback_dev;
@@ -272,11 +275,19 @@ gart_map_single(struct device *dev, phys_addr_t paddr, size_t size, int dir)
        return bus;
 }
 
+static dma_addr_t gart_map_single(struct device *dev, phys_addr_t paddr,
+                                 size_t size, int dir)
+{
+       return gart_map_page(dev, pfn_to_page(paddr >> PAGE_SHIFT),
+                            paddr & ~PAGE_MASK, size, dir, NULL);
+}
+
 /*
  * Free a DMA mapping.
  */
-static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
-                             size_t size, int direction)
+static void gart_unmap_page(struct device *dev, dma_addr_t dma_addr,
+                           size_t size, enum dma_data_direction dir,
+                           struct dma_attrs *attrs)
 {
        unsigned long iommu_page;
        int npages;
@@ -295,6 +306,12 @@ static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
        free_iommu(iommu_page, npages);
 }
 
+static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
+                             size_t size, int direction)
+{
+       gart_unmap_page(dev, dma_addr, size, direction, NULL);
+}
+
 /*
  * Wrapper for pci_unmap_single working with scatterlists.
  */
@@ -712,6 +729,8 @@ static struct dma_mapping_ops gart_dma_ops = {
        .unmap_single                   = gart_unmap_single,
        .map_sg                         = gart_map_sg,
        .unmap_sg                       = gart_unmap_sg,
+       .map_page                       = gart_map_page,
+       .unmap_page                     = gart_unmap_page,
        .alloc_coherent                 = gart_alloc_coherent,
        .free_coherent                  = gart_free_coherent,
 };