From: Thierry Reding Date: Fri, 8 Jun 2018 13:00:05 +0000 (+0200) Subject: drm/tegra: gem: Use sg_alloc_table_from_pages() X-Git-Tag: v5.5-rc1~128^2~20^2~50 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=acf6b77c4c3dc38de1e435d114c267cd8dedc913;p=linux.git drm/tegra: gem: Use sg_alloc_table_from_pages() Instead of manually creating the SG table for a discontiguous buffer, use the existing sg_alloc_table_from_pages(). Note that this is not safe to be used with the ARM DMA/IOMMU integration code because that will not ensure that the whole buffer is mapped contiguously. Depending on the size of the individual entries the mapping may end up containing holes to ensure alignment. However, we only ever use these buffers with explicit IOMMU API usage and know how to avoid these holes. Signed-off-by: Thierry Reding --- diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c index 00701cadaceb..d2f88cc3134f 100644 --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -508,14 +508,9 @@ tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach, return NULL; if (bo->pages) { - struct scatterlist *sg; - unsigned int i; - - if (sg_alloc_table(sgt, bo->num_pages, GFP_KERNEL)) + if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages, + 0, gem->size, GFP_KERNEL) < 0) goto free; - - for_each_sg(sgt->sgl, sg, bo->num_pages, i) - sg_set_page(sg, bo->pages[i], PAGE_SIZE, 0); } else { if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova, gem->size) < 0)