[SPARC64]: Implement pci_dma_error().

arch/sparc64/kernel/pci_iommu.c

@@ -352,8 +352,7 @@ dma_addr_t pci_map_single(struct pci_dev *pdev, void *ptr, size_t sz, int direct
 
 bad:
 	spin_unlock_irqrestore(&iommu->lock, flags);
-	BUG();
-	return 0;
+	return PCI_DMA_ERROR_CODE;
 }
 
 /* Unmap a single streaming mode DMA translation. */
@@ -580,8 +579,7 @@ int pci_map_sg(struct pci_dev *pdev, struct scatterlist *sglist, int nelems, int
 
 bad:
 	spin_unlock_irqrestore(&iommu->lock, flags);
-	BUG();
-	return 0;
+	return PCI_DMA_ERROR_CODE;
 }
 
 /* Unmap a set of streaming mode DMA translations. */

include/asm-sparc64/pci.h

@@ -213,6 +213,13 @@ pci_dac_dma_sync_single_for_device(struct pci_dev *pdev, dma64_addr_t dma_addr,
 	 */
 }
 
+#define PCI_DMA_ERROR_CODE	(~(dma_addr_t)0x0)
+
+static inline int pci_dma_error(dma_addr_t dma_addr)
+{
+	return (dma_addr == PCI_DMA_ERROR_CODE);
+}
+
 /* Return the index of the PCI controller for device PDEV. */
 
 extern int pci_domain_nr(struct pci_bus *bus);