[PATCH AUTOSEL 6.6 02/18] dma-mapping: benchmark: avoid needless copy_to_user if benchmark fails

Sasha Levin
2024-06-05T12:04:12Z

From: Fedor Pchelkin <pchelkin@ispras.ru>

[ Upstream commit f7c9ccaadffd13066353332c13d7e9bf73b8f92d ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/dma/map_benchmark.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
index 02205ab53b7e9..28ca165cb62c1 100644
--- a/kernel/dma/map_benchmark.c
+++ b/kernel/dma/map_benchmark.c
@@ -252,6 +252,9 @@ 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;
--
2.43.0