swiotlb: use phys_to_dma and dma_to_phys

This converts swiotlb to use phys_to_dma and dma_to_phys instead of
swiotlb_phys_to_bus() and swiotlb_bus_to_phys().

swiotlb_phys_to_bus() and swiotlb_bus_to_phys() are not necessary so
this patch also removes them.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>

include/linux/swiotlb.h

@@ -23,11 +23,6 @@ struct scatterlist;
 extern void
 swiotlb_init(void);
 
-extern dma_addr_t swiotlb_phys_to_bus(struct device *hwdev,
-				      phys_addr_t address);
-extern phys_addr_t swiotlb_bus_to_phys(struct device *hwdev,
-				       dma_addr_t address);
-
 extern void
 *swiotlb_alloc_coherent(struct device *hwdev, size_t size,
 			dma_addr_t *dma_handle, gfp_t flags);

lib/swiotlb.c

@@ -114,21 +114,11 @@ setup_io_tlb_npages(char *str)
 __setup("swiotlb=", setup_io_tlb_npages);
 /* make io_tlb_overflow tunable too? */
 
-dma_addr_t __weak swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr)
-{
-	return paddr;
-}
-
-phys_addr_t __weak swiotlb_bus_to_phys(struct device *hwdev, dma_addr_t baddr)
-{
-	return baddr;
-}
-
 /* Note that this doesn't work with highmem page */
 static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
 				      volatile void *address)
 {
-	return swiotlb_phys_to_bus(hwdev, virt_to_phys(address));
+	return phys_to_dma(hwdev, virt_to_phys(address));
 }
 
 static void swiotlb_print_info(unsigned long bytes)
@@ -567,7 +557,7 @@ void
 swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
 		      dma_addr_t dev_addr)
 {
-	phys_addr_t paddr = swiotlb_bus_to_phys(hwdev, dev_addr);
+	phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
 
 	WARN_ON(irqs_disabled());
 	if (!is_swiotlb_buffer(paddr))
@@ -612,7 +602,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
 			    struct dma_attrs *attrs)
 {
 	phys_addr_t phys = page_to_phys(page) + offset;
-	dma_addr_t dev_addr = swiotlb_phys_to_bus(dev, phys);
+	dma_addr_t dev_addr = phys_to_dma(dev, phys);
 	void *map;
 
 	BUG_ON(dir == DMA_NONE);
@@ -656,7 +646,7 @@ EXPORT_SYMBOL_GPL(swiotlb_map_page);
 static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
 			 size_t size, int dir)
 {
-	phys_addr_t paddr = swiotlb_bus_to_phys(hwdev, dev_addr);
+	phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
 
 	BUG_ON(dir == DMA_NONE);
 
@@ -699,7 +689,7 @@ static void
 swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
 		    size_t size, int dir, int target)
 {
-	phys_addr_t paddr = swiotlb_bus_to_phys(hwdev, dev_addr);
+	phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
 
 	BUG_ON(dir == DMA_NONE);
 
@@ -788,7 +778,7 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
 
 	for_each_sg(sgl, sg, nelems, i) {
 		phys_addr_t paddr = sg_phys(sg);
-		dma_addr_t dev_addr = swiotlb_phys_to_bus(hwdev, paddr);
+		dma_addr_t dev_addr = phys_to_dma(hwdev, paddr);
 
 		if (swiotlb_force ||
 		    !dma_capable(hwdev, dev_addr, sg->length)) {