dma-mapping: remove the mapping_error dma_map_ops method

No users left except for vmd which just forwards it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/pci/controller/vmd.c

@@ -394,11 +394,6 @@ static void vmd_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 	vmd_dma_ops(dev)->sync_sg_for_device(to_vmd_dev(dev), sg, nents, dir);
 }
 
-static int vmd_mapping_error(struct device *dev, dma_addr_t addr)
-{
-	return vmd_dma_ops(dev)->mapping_error(to_vmd_dev(dev), addr);
-}
-
 static int vmd_dma_supported(struct device *dev, u64 mask)
 {
 	return vmd_dma_ops(dev)->dma_supported(to_vmd_dev(dev), mask);
@@ -446,7 +441,6 @@ static void vmd_setup_dma_ops(struct vmd_dev *vmd)
 	ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_device);
 	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_cpu);
 	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_device);
-	ASSIGN_VMD_DMA_OPS(source, dest, mapping_error);
 	ASSIGN_VMD_DMA_OPS(source, dest, dma_supported);
 	ASSIGN_VMD_DMA_OPS(source, dest, get_required_mask);
 	add_dma_domain(domain);

include/linux/dma-mapping.h

@@ -128,7 +128,6 @@ struct dma_map_ops {
 				   enum dma_data_direction dir);
 	void (*cache_sync)(struct device *dev, void *vaddr, size_t size,
 			enum dma_data_direction direction);
-	int (*mapping_error)(struct device *dev, dma_addr_t dma_addr);
 	int (*dma_supported)(struct device *dev, u64 mask);
 	u64 (*get_required_mask)(struct device *dev);
 };
@@ -580,12 +579,8 @@ static inline void dma_free_coherent(struct device *dev, size_t size,
 
 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 {
-	const struct dma_map_ops *ops = get_dma_ops(dev);
-
 	debug_dma_mapping_error(dev, dma_addr);
 
-	if (ops->mapping_error)
-		return ops->mapping_error(dev, dma_addr);
 	if (dma_addr == DMA_MAPPING_ERROR)
 		return 1;
 	return 0;