[PATCH 2/3] drm/cma-helper: Use sgt_dma_contiguous() helper

[Daniel Vetter]

On Tue, Dec 03, 2019 at 05:32:02PM +0100, Thierry Reding wrote:
> From: Thierry Reding <treding at nvidia.com>
> 
> Functionality to count the number of contiguous DMA chunks in an SG
> table has been added to the scatterlist library. Use this functionality
> to replace an open-coded version in the GEM/CMA helpers.
> 
> Signed-off-by: Thierry Reding <treding at nvidia.com>

On the first 2 patches:

Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>

> ---
>  drivers/gpu/drm/drm_gem_cma_helper.c | 22 ++--------------------
>  1 file changed, 2 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
> index 12e98fb28229..5bbae9654cc6 100644
> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
> @@ -471,26 +471,8 @@ drm_gem_cma_prime_import_sg_table(struct drm_device *dev,
>  {
>  	struct drm_gem_cma_object *cma_obj;
>  
> -	if (sgt->nents != 1) {
> -		/* check if the entries in the sg_table are contiguous */
> -		dma_addr_t next_addr = sg_dma_address(sgt->sgl);
> -		struct scatterlist *s;
> -		unsigned int i;
> -
> -		for_each_sg(sgt->sgl, s, sgt->nents, i) {
> -			/*
> -			 * sg_dma_address(s) is only valid for entries
> -			 * that have sg_dma_len(s) != 0
> -			 */
> -			if (!sg_dma_len(s))
> -				continue;
> -
> -			if (sg_dma_address(s) != next_addr)
> -				return ERR_PTR(-EINVAL);
> -
> -			next_addr = sg_dma_address(s) + sg_dma_len(s);
> -		}
> -	}
> +	if (!sgt_dma_contiguous(sgt))
> +		return ERR_PTR(-EINVAL);
>  
>  	/* Create a CMA GEM buffer. */
>  	cma_obj = __drm_gem_cma_create(dev, attach->dmabuf->size);
> -- 
> 2.23.0
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch