dmatest: check for dma mapping error

The kernel emits a warning if CONFIG_DMA_API_DEBUG=y:

  WARNING: at lib/dma-debug.c:933 check_unmap+0x5d6/0x6ac()
  dw_dmac dw_dmac.0: DMA-API: device driver failed to check map error[device address=0x0000000035698305] [size=14365 bytes] [mapped as single]

Fix this by adding the required checking of the dma_map_single() return
value.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 21 insertions, 1 deletions

diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index 6be893baadd9..64b048d7fba7 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -367,15 +367,35 @@ static int dmatest_func(void *data)
 
                         dma_srcs[i] = dma_map_single(dev->dev, buf, len,
                                                      DMA_TO_DEVICE);
+                        ret = dma_mapping_error(dev->dev, dma_srcs[i]);
+                        if (ret) {
+                                unmap_src(dev->dev, dma_srcs, len, i);
+                                pr_warn("%s: #%u: mapping error %d with "
+                                        "src_off=0x%x len=0x%x\n",
+                                        thread_name, total_tests - 1, ret,
+                                        src_off, len);
+                                failed_tests++;
+                                continue;
+                        }
                 }
                 /* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
                 for (i = 0; i < dst_cnt; i++) {
                         dma_dsts[i] = dma_map_single(dev->dev, thread->dsts[i],
                                                      test_buf_size,
                                                      DMA_BIDIRECTIONAL);
+                        ret = dma_mapping_error(dev->dev, dma_dsts[i]);
+                        if (ret) {
+                                unmap_src(dev->dev, dma_srcs, len, src_cnt);
+                                unmap_dst(dev->dev, dma_dsts, test_buf_size, i);
+                                pr_warn("%s: #%u: mapping error %d with "
+                                        "dst_off=0x%x len=0x%x\n",
+                                        thread_name, total_tests - 1, ret,
+                                        dst_off, test_buf_size);
+                                failed_tests++;
+                                continue;
+                        }
                 }
 
-
                 if (thread->type == DMA_MEMCPY)
                         tx = dev->device_prep_dma_memcpy(chan,
                                                          dma_dsts[0] + dst_off,