Re: [PATCH] media: vb2 vmalloc: Constify dma_buf_ops structures.

From: Marek Szyprowski
Date: Tue Jul 04 2017 - 01:23:30 EST


Hi Arvind,

On 2017-07-01 13:37, 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
3171 192 0 3363 d23 drivers/media/v4l2-core/videobuf2-vmalloc.o

File size After adding 'const':
text data bss dec hex filename
3291 80 0 3371 d2b drivers/media/v4l2-core/videobuf2-vmalloc.o

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

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

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

diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c
index b337d78..6bc130f 100644
--- a/drivers/media/v4l2-core/videobuf2-vmalloc.c
+++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c
@@ -338,7 +338,7 @@ static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
return vb2_vmalloc_mmap(dbuf->priv, vma);
}
-static struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
+static const struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
.attach = vb2_vmalloc_dmabuf_ops_attach,
.detach = vb2_vmalloc_dmabuf_ops_detach,
.map_dma_buf = vb2_vmalloc_dmabuf_ops_map,

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