Re: [PATCH] media: vb2 dma-contig: Constify dma_buf_ops structures.

From: Marek Szyprowski
Date: Tue Jul 04 2017 - 01:23:11 EST


Hi Arvind,

On 2017-07-01 13:27, Arvind Yadav wrote:
dma_buf_ops are not supposed to change at runtime. All functions
working with dma_buf_ops provided by <linux/dma-buf.h> work with
const dma_buf_ops. So mark the non-const structs as const.

File size before:
text data bss dec hex filename
6035 272 0 6307 18a3 drivers/media/v4l2-core/videobuf2-dma-contig.o

File size After adding 'const':
text data bss dec hex filename
6155 160 0 6315 18ab drivers/media/v4l2-core/videobuf2-dma-contig.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>

Thanks!
Acked-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>

---
drivers/media/v4l2-core/videobuf2-dma-contig.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index 4f246d1..5b90a66 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -352,7 +352,7 @@ static int vb2_dc_dmabuf_ops_mmap(struct dma_buf *dbuf,
return vb2_dc_mmap(dbuf->priv, vma);
}
-static struct dma_buf_ops vb2_dc_dmabuf_ops = {
+static const struct dma_buf_ops vb2_dc_dmabuf_ops = {
.attach = vb2_dc_dmabuf_ops_attach,
.detach = vb2_dc_dmabuf_ops_detach,
.map_dma_buf = vb2_dc_dmabuf_ops_map,

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland