dma-direct: merge swiotlb_dma_ops into the dma_direct code

While the dma-direct code is (relatively) clean and simple we actually
have to use the swiotlb ops for the mapping on many architectures due
to devices with addressing limits.  Instead of keeping two
implementations around this commit allows the dma-direct
implementation to call the swiotlb bounce buffering functions and
thus share the guts of the mapping implementation.  This also
simplified the dma-mapping setup on a few architectures where we
don't have to differenciate which implementation to use.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>

2 files changed, 42 insertions, 44 deletions

diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index 1aa73f4907ae..3b0a3ea3876d 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -63,7 +63,19 @@ void __dma_direct_free_pages(struct device *dev, size_t size, struct page *page)
 dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
 		unsigned long offset, size_t size, enum dma_data_direction dir,
 		unsigned long attrs);
+void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
+		size_t size, enum dma_data_direction dir, unsigned long attrs);
 int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
 		enum dma_data_direction dir, unsigned long attrs);
+void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
+		int nents, enum dma_data_direction dir, unsigned long attrs);
+void dma_direct_sync_single_for_device(struct device *dev,
+		dma_addr_t addr, size_t size, enum dma_data_direction dir);
+void dma_direct_sync_sg_for_device(struct device *dev,
+		struct scatterlist *sgl, int nents, enum dma_data_direction dir);
+void dma_direct_sync_single_for_cpu(struct device *dev,
+		dma_addr_t addr, size_t size, enum dma_data_direction dir);
+void dma_direct_sync_sg_for_cpu(struct device *dev,
+		struct scatterlist *sgl, int nents, enum dma_data_direction dir);
 int dma_direct_supported(struct device *dev, u64 mask);
 #endif /* _LINUX_DMA_DIRECT_H */
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 14aec0b70dd9..7c007ed7505f 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -16,8 +16,6 @@ enum swiotlb_force {
 	SWIOTLB_NO_FORCE,	/* swiotlb=noforce */
 };
 
-extern enum swiotlb_force swiotlb_force;
-
 /*
  * Maximum allowable number of contiguous slabs to map,
  * must be a power of 2.  What is the appropriate value ?
@@ -62,56 +60,44 @@ extern void swiotlb_tbl_sync_single(struct device *hwdev,
 				    size_t size, enum dma_data_direction dir,
 				    enum dma_sync_target target);
 
-/* Accessory functions. */
-
-extern dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
-				   unsigned long offset, size_t size,
-				   enum dma_data_direction dir,
-				   unsigned long attrs);
-extern void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
-			       size_t size, enum dma_data_direction dir,
-			       unsigned long attrs);
-
-extern int
-swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
-		     enum dma_data_direction dir,
-		     unsigned long attrs);
-
-extern void
-swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
-		       int nelems, enum dma_data_direction dir,
-		       unsigned long attrs);
-
-extern void
-swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
-			    size_t size, enum dma_data_direction dir);
-
-extern void
-swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
-			int nelems, enum dma_data_direction dir);
-
-extern void
-swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
-			       size_t size, enum dma_data_direction dir);
-
-extern void
-swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
-			   int nelems, enum dma_data_direction dir);
-
 extern int
 swiotlb_dma_supported(struct device *hwdev, u64 mask);
 
 #ifdef CONFIG_SWIOTLB
-extern void __init swiotlb_exit(void);
+extern enum swiotlb_force swiotlb_force;
+extern phys_addr_t io_tlb_start, io_tlb_end;
+
+static inline bool is_swiotlb_buffer(phys_addr_t paddr)
+{
+	return paddr >= io_tlb_start && paddr < io_tlb_end;
+}
+
+bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
+		size_t size, enum dma_data_direction dir, unsigned long attrs);
+void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 #else
-static inline void swiotlb_exit(void) { }
-static inline unsigned int swiotlb_max_segment(void) { return 0; }
-#endif
+#define swiotlb_force SWIOTLB_NO_FORCE
+static inline bool is_swiotlb_buffer(phys_addr_t paddr)
+{
+	return false;
+}
+static inline bool swiotlb_map(struct device *dev, phys_addr_t *phys,
+		dma_addr_t *dma_addr, size_t size, enum dma_data_direction dir,
+		unsigned long attrs)
+{
+	return false;
+}
+static inline void swiotlb_exit(void)
+{
+}
+static inline unsigned int swiotlb_max_segment(void)
+{
+	return 0;
+}
+#endif /* CONFIG_SWIOTLB */
 
 extern void swiotlb_print_info(void);
 extern void swiotlb_set_max_segment(unsigned int);
 
-extern const struct dma_map_ops swiotlb_dma_ops;
-
 #endif /* __LINUX_SWIOTLB_H */