dma-mapping: benchmark: avoid needless copy_to_user if benchmark fails
If do_map_benchmark() has failed, there is nothing useful to copy back
to userspace.
Suggested-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
index 2478957..a6edb1e 100644
--- a/kernel/dma/map_benchmark.c
+++ b/kernel/dma/map_benchmark.c
@@ -256,6 +256,9 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
* dma_mask changed by benchmark
*/
dma_set_mask(map->dev, old_dma_mask);
+
+ if (ret)
+ return ret;
break;
default:
return -EINVAL;
