dma-direct: comment the dma_direct_free calling convention

Christoph Hellwig · Christoph Hellwig · commit 42ed64524d84 · 2018-02-12T15:59:07.000Z
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
@@ -84,6 +84,10 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
 	return page_address(page);
 }
 
+/*
+ * NOTE: this function must never look at the dma_addr argument, because we want
+ * to be able to use it as a helper for iommu implementations as well.
+ */
 void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
 		dma_addr_t dma_addr, unsigned long attrs)
 {

Original file line number	Diff line number	Diff line change
`@@ -84,6 +84,10 @@ void dma_direct_alloc(struct device dev, size_t size, dma_addr_t *dma_handle,`
`84`	`84`	`return page_address(page);`
`85`	`85`	`}`
`86`	`86`
	`87`	`+/*`
	`88`	`+ * NOTE: this function must never look at the dma_addr argument, because we want`
	`89`	`+ * to be able to use it as a helper for iommu implementations as well.`
	`90`	`+ */`
`87`	`91`	`void dma_direct_free(struct device dev, size_t size, void cpu_addr,`
`88`	`92`	`dma_addr_t dma_addr, unsigned long attrs)`
`89`	`93`	`{`