Add missing DMA ops

For the initial architecture submission, not all of the DMA ops were
implemented.  This patch adds the *map_page and *map_sg variants of the
DMA mapping ops.

This patch is currently of interest mainly to some drivers that haven't
been submitted upstream yet.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c
index 968d3ee..f1c8ee2 100644
--- a/arch/openrisc/kernel/dma.c
+++ b/arch/openrisc/kernel/dma.c
@@ -154,6 +154,33 @@
 	/* Nothing special to do here... */
 }
 
+int or1k_map_sg(struct device *dev, struct scatterlist *sg,
+		int nents, enum dma_data_direction dir,
+		struct dma_attrs *attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		s->dma_address = or1k_map_page(dev, sg_page(s), s->offset,
+					       s->length, dir, NULL);
+	}
+
+	return nents;
+}
+
+void or1k_unmap_sg(struct device *dev, struct scatterlist *sg,
+		   int nents, enum dma_data_direction dir,
+		   struct dma_attrs *attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		or1k_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir, NULL);
+	}
+}
+
 void or1k_sync_single_for_cpu(struct device *dev,
 			      dma_addr_t dma_handle, size_t size,
 			      enum dma_data_direction dir)
@@ -187,5 +214,4 @@
 
 	return 0;
 }
-
 fs_initcall(dma_init);