1 files changed, 78 insertions, 13 deletions

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 2b06a809d0b9..8349a9f2c345 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -156,7 +156,7 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
 		addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);
 	else
 		addr = ops->map_page(dev, page, offset, size, dir, attrs);
-	debug_dma_map_page(dev, page, offset, size, dir, addr);
+	debug_dma_map_page(dev, page, offset, size, dir, addr, attrs);
 
 	return addr;
 }
@@ -177,12 +177,8 @@ void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
 }
 EXPORT_SYMBOL(dma_unmap_page_attrs);
 
-/*
- * dma_maps_sg_attrs returns 0 on error and > 0 on success.
- * It should never return a value < 0.
- */
-int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
-		enum dma_data_direction dir, unsigned long attrs)
+static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
+	 int nents, enum dma_data_direction dir, unsigned long attrs)
 {
 	const struct dma_map_ops *ops = get_dma_ops(dev);
 	int ents;
@@ -197,13 +193,82 @@ int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
 		ents = dma_direct_map_sg(dev, sg, nents, dir, attrs);
 	else
 		ents = ops->map_sg(dev, sg, nents, dir, attrs);
-	BUG_ON(ents < 0);
-	debug_dma_map_sg(dev, sg, nents, ents, dir);
+
+	if (ents > 0)
+		debug_dma_map_sg(dev, sg, nents, ents, dir, attrs);
+	else if (WARN_ON_ONCE(ents != -EINVAL && ents != -ENOMEM &&
+			      ents != -EIO))
+		return -EIO;
 
 	return ents;
 }
+
+/**
+ * dma_map_sg_attrs - Map the given buffer for DMA
+ * @dev:	The device for which to perform the DMA operation
+ * @sg:		The sg_table object describing the buffer
+ * @nents:	Number of entries to map
+ * @dir:	DMA direction
+ * @attrs:	Optional DMA attributes for the map operation
+ *
+ * Maps a buffer described by a scatterlist passed in the sg argument with
+ * nents segments for the @dir DMA operation by the @dev device.
+ *
+ * Returns the number of mapped entries (which can be less than nents)
+ * on success. Zero is returned for any error.
+ *
+ * dma_unmap_sg_attrs() should be used to unmap the buffer with the
+ * original sg and original nents (not the value returned by this funciton).
+ */
+unsigned int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
+		    int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+	int ret;
+
+	ret = __dma_map_sg_attrs(dev, sg, nents, dir, attrs);
+	if (ret < 0)
+		return 0;
+	return ret;
+}
 EXPORT_SYMBOL(dma_map_sg_attrs);
 
+/**
+ * dma_map_sgtable - Map the given buffer for DMA
+ * @dev:	The device for which to perform the DMA operation
+ * @sgt:	The sg_table object describing the buffer
+ * @dir:	DMA direction
+ * @attrs:	Optional DMA attributes for the map operation
+ *
+ * Maps a buffer described by a scatterlist stored in the given sg_table
+ * object for the @dir DMA operation by the @dev device. After success, the
+ * ownership for the buffer is transferred to the DMA domain.  One has to
+ * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the
+ * ownership of the buffer back to the CPU domain before touching the
+ * buffer by the CPU.
+ *
+ * Returns 0 on success or a negative error code on error. The following
+ * error codes are supported with the given meaning:
+ *
+ *   -EINVAL	An invalid argument, unaligned access or other error
+ *		in usage. Will not succeed if retried.
+ *   -ENOMEM	Insufficient resources (like memory or IOVA space) to
+ *		complete the mapping. Should succeed if retried later.
+ *   -EIO	Legacy error code with an unknown meaning. eg. this is
+ *		returned if a lower level call returned DMA_MAPPING_ERROR.
+ */
+int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
+		    enum dma_data_direction dir, unsigned long attrs)
+{
+	int nents;
+
+	nents = __dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
+	if (nents < 0)
+		return nents;
+	sgt->nents = nents;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dma_map_sgtable);
+
 void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
 				      int nents, enum dma_data_direction dir,
 				      unsigned long attrs)
@@ -240,7 +305,7 @@ dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
 	else if (ops->map_resource)
 		addr = ops->map_resource(dev, phys_addr, size, dir, attrs);
 
-	debug_dma_map_resource(dev, phys_addr, size, dir, addr);
+	debug_dma_map_resource(dev, phys_addr, size, dir, addr, attrs);
 	return addr;
 }
 EXPORT_SYMBOL(dma_map_resource);
@@ -445,7 +510,7 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 	else
 		return NULL;
 
-	debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
+	debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr, attrs);
 	return cpu_addr;
 }
 EXPORT_SYMBOL(dma_alloc_attrs);
@@ -501,7 +566,7 @@ struct page *dma_alloc_pages(struct device *dev, size_t size,
 	struct page *page = __dma_alloc_pages(dev, size, dma_handle, dir, gfp);
 
 	if (page)
-		debug_dma_map_page(dev, page, 0, size, dir, *dma_handle);
+		debug_dma_map_page(dev, page, 0, size, dir, *dma_handle, 0);
 	return page;
 }
 EXPORT_SYMBOL_GPL(dma_alloc_pages);
@@ -579,7 +644,7 @@ struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
 
 	if (sgt) {
 		sgt->nents = 1;
-		debug_dma_map_sg(dev, sgt->sgl, sgt->orig_nents, 1, dir);
+		debug_dma_map_sg(dev, sgt->sgl, sgt->orig_nents, 1, dir, attrs);
 	}
 	return sgt;
 }