x86, ia64: remove duplicated swiotlb code

This adds swiotlb_map_page and swiotlb_unmap_page to lib/swiotlb.c and
remove IA64 and X86's swiotlb_map_page and swiotlb_unmap_page.

This also removes unnecessary swiotlb_map_single, swiotlb_map_single_attrs,
swiotlb_unmap_single and swiotlb_unmap_single_attrs.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/ia64/kernel/pci-swiotlb.c

@@ -16,22 +16,6 @@ EXPORT_SYMBOL(swiotlb);
 /* Set this to 1 if there is a HW IOMMU in the system */
 int iommu_detected __read_mostly;
 
-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_attrs(dev, page_address(page) + offset, size,
-					dir, attrs);
-}
-
-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_attrs(dev, dma_handle, size, dir, attrs);
-}
-
 struct dma_map_ops swiotlb_dma_ops = {
 	.alloc_coherent = swiotlb_alloc_coherent,
 	.free_coherent = swiotlb_free_coherent,

arch/x86/kernel/pci-swiotlb_64.c

@@ -38,23 +38,6 @@ int __weak swiotlb_arch_range_needs_mapping(void *ptr, size_t size)
 	return 0;
 }
 
-/* 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)
 {

include/linux/swiotlb.h

@@ -41,20 +41,13 @@ extern void
 swiotlb_free_coherent(struct device *hwdev, size_t size,
 		      void *vaddr, dma_addr_t dma_handle);
 
-extern dma_addr_t
-swiotlb_map_single(struct device *hwdev, void *ptr, size_t size, int dir);
-
-extern void
-swiotlb_unmap_single(struct device *hwdev, dma_addr_t dev_addr,
-		     size_t size, int dir);
-
-extern dma_addr_t
-swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size,
-			 int dir, struct dma_attrs *attrs);
-
-extern void
-swiotlb_unmap_single_attrs(struct device *hwdev, dma_addr_t dev_addr,
-			   size_t size, int dir, struct dma_attrs *attrs);
+extern 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);
+extern void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
+			       size_t size, enum dma_data_direction dir,
+			       struct dma_attrs *attrs);
 
 extern int
 swiotlb_map_sg(struct device *hwdev, struct scatterlist *sg, int nents,

lib/swiotlb.c

@@ -636,11 +636,14 @@ swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
  * Once the device is given the dma address, the device owns this memory until
  * either swiotlb_unmap_single or swiotlb_dma_sync_single is performed.
  */
-dma_addr_t
-swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size,
-			 int dir, struct dma_attrs *attrs)
-{
-	dma_addr_t dev_addr = swiotlb_virt_to_bus(hwdev, ptr);
+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)
+{
+	phys_addr_t phys = page_to_phys(page) + offset;
+	void *ptr = page_address(page) + offset;
+	dma_addr_t dev_addr = swiotlb_phys_to_bus(dev, phys);
 	void *map;
 
 	BUG_ON(dir == DMA_NONE);
@@ -649,37 +652,30 @@ swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size,
 	 * we can safely return the device addr and not worry about bounce
 	 * buffering it.
 	 */
-	if (!address_needs_mapping(hwdev, dev_addr, size) &&
+	if (!address_needs_mapping(dev, dev_addr, size) &&
 	    !range_needs_mapping(ptr, size))
 		return dev_addr;
 
 	/*
 	 * Oh well, have to allocate and map a bounce buffer.
 	 */
-	map = map_single(hwdev, virt_to_phys(ptr), size, dir);
+	map = map_single(dev, phys, size, dir);
 	if (!map) {
-		swiotlb_full(hwdev, size, dir, 1);
+		swiotlb_full(dev, size, dir, 1);
 		map = io_tlb_overflow_buffer;
 	}
 
-	dev_addr = swiotlb_virt_to_bus(hwdev, map);
+	dev_addr = swiotlb_virt_to_bus(dev, map);
 
 	/*
 	 * Ensure that the address returned is DMA'ble
 	 */
-	if (address_needs_mapping(hwdev, dev_addr, size))
+	if (address_needs_mapping(dev, dev_addr, size))
 		panic("map_single: bounce buffer is not DMA'ble");
 
 	return dev_addr;
 }
-EXPORT_SYMBOL(swiotlb_map_single_attrs);
-
-dma_addr_t
-swiotlb_map_single(struct device *hwdev, void *ptr, size_t size, int dir)
-{
-	return swiotlb_map_single_attrs(hwdev, ptr, size, dir, NULL);
-}
-EXPORT_SYMBOL(swiotlb_map_single);
+EXPORT_SYMBOL_GPL(swiotlb_map_page);
 
 /*
  * Unmap a single streaming mode DMA translation.  The dma_addr and size must
@@ -689,9 +685,9 @@ EXPORT_SYMBOL(swiotlb_map_single);
  * After this call, reads by the cpu to the buffer are guaranteed to see
  * whatever the device wrote there.
  */
-void
-swiotlb_unmap_single_attrs(struct device *hwdev, dma_addr_t dev_addr,
-			   size_t size, int dir, struct dma_attrs *attrs)
+void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
+			size_t size, enum dma_data_direction dir,
+			struct dma_attrs *attrs)
 {
 	char *dma_addr = swiotlb_bus_to_virt(dev_addr);
 
@@ -701,15 +697,7 @@ swiotlb_unmap_single_attrs(struct device *hwdev, dma_addr_t dev_addr,
 	else if (dir == DMA_FROM_DEVICE)
 		dma_mark_clean(dma_addr, size);
 }
-EXPORT_SYMBOL(swiotlb_unmap_single_attrs);
-
-void
-swiotlb_unmap_single(struct device *hwdev, dma_addr_t dev_addr, size_t size,
-		     int dir)
-{
-	return swiotlb_unmap_single_attrs(hwdev, dev_addr, size, dir, NULL);
-}
-EXPORT_SYMBOL(swiotlb_unmap_single);
+EXPORT_SYMBOL_GPL(swiotlb_unmap_page);
 
 /*
  * Make physical memory consistent for a single streaming mode DMA translation