virtio-blk: fixup coccinelle warnings

coccicheck complains about the use of snprintf() in sysfs show
functions:
WARNING  use scnprintf or sprintf

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Ye Guojin <ye.guojin@zte.com.cn>
Link: https://lore.kernel.org/r/20211021065111.1047824-1-ye.guojin@zte.com.cn
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 20f230bfe5b3502aa0a395f28a7490bfacd39d52..bcb02e4a08099a88ecc2664d91ad795961926a4b 100644 (file)
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -704,7 +704,7 @@ cache_type_show(struct device *dev, struct device_attribute *attr, char *buf)
        u8 writeback = virtblk_get_cache_mode(vblk->vdev);
 
        BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types));
-       return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]);
+       return sysfs_emit(buf, "%s\n", virtblk_cache_types[writeback]);
 }
 
 static DEVICE_ATTR_RW(cache_type);