dmatest: implement two helpers to unmap dma memory

The unmap_src() and unmap_dst() will be used later as well.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/dma/dmatest.c

@@ -228,6 +228,20 @@ static void dmatest_callback(void *arg)
 	wake_up_all(done->wait);
 }
 
+static inline void unmap_src(struct device *dev, dma_addr_t *addr, size_t len,
+			     unsigned int count)
+{
+	while (count--)
+		dma_unmap_single(dev, addr[count], len, DMA_TO_DEVICE);
+}
+
+static inline void unmap_dst(struct device *dev, dma_addr_t *addr, size_t len,
+			     unsigned int count)
+{
+	while (count--)
+		dma_unmap_single(dev, addr[count], len, DMA_BIDIRECTIONAL);
+}
+
 /*
  * This function repeatedly tests DMA transfers of various lengths and
  * offsets for a given operation type until it is told to exit by
@@ -383,13 +397,8 @@ static int dmatest_func(void *data)
 		}
 
 		if (!tx) {
-			for (i = 0; i < src_cnt; i++)
-				dma_unmap_single(dev->dev, dma_srcs[i], len,
-						 DMA_TO_DEVICE);
-			for (i = 0; i < dst_cnt; i++)
-				dma_unmap_single(dev->dev, dma_dsts[i],
-						 test_buf_size,
-						 DMA_BIDIRECTIONAL);
+			unmap_src(dev->dev, dma_srcs, len, src_cnt);
+			unmap_dst(dev->dev, dma_dsts, test_buf_size, dst_cnt);
 			pr_warning("%s: #%u: prep error with src_off=0x%x "
 					"dst_off=0x%x len=0x%x\n",
 					thread_name, total_tests - 1,
@@ -443,9 +452,7 @@ static int dmatest_func(void *data)
 		}
 
 		/* Unmap by myself (see DMA_COMPL_SKIP_DEST_UNMAP above) */
-		for (i = 0; i < dst_cnt; i++)
-			dma_unmap_single(dev->dev, dma_dsts[i], test_buf_size,
-					 DMA_BIDIRECTIONAL);
+		unmap_dst(dev->dev, dma_dsts, test_buf_size, dst_cnt);
 
 		error_count = 0;