drm: mediatek: use common helper for a scatterlist contiguity check

Use common helper for checking the contiguity of the imported dma-buf and
do this check before allocating resources, so the error path is simpler.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
index 6190cc3..3654ec7 100644 (file)
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -212,37 +212,21 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
                        struct dma_buf_attachment *attach, struct sg_table *sg)
 {
        struct mtk_drm_gem_obj *mtk_gem;
-       int ret;
-       struct scatterlist *s;
-       unsigned int i;
-       dma_addr_t expected;
 
-       mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
+       /* check if the entries in the sg_table are contiguous */
+       if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) {
+               DRM_ERROR("sg_table is not contiguous");
+               return ERR_PTR(-EINVAL);
+       }
 
+       mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size);
        if (IS_ERR(mtk_gem))
                return ERR_CAST(mtk_gem);
 
-       expected = sg_dma_address(sg->sgl);
-       for_each_sg(sg->sgl, s, sg->nents, i) {
-               if (!sg_dma_len(s))
-                       break;
-
-               if (sg_dma_address(s) != expected) {
-                       DRM_ERROR("sg_table is not contiguous");
-                       ret = -EINVAL;
-                       goto err_gem_free;
-               }
-               expected = sg_dma_address(s) + sg_dma_len(s);
-       }
-
        mtk_gem->dma_addr = sg_dma_address(sg->sgl);
        mtk_gem->sg = sg;
 
        return &mtk_gem->base;
-
-err_gem_free:
-       kfree(mtk_gem);
-       return ERR_PTR(ret);
 }
 
 void *mtk_drm_gem_prime_vmap(struct drm_gem_object *obj)