Hi Marek, On 10/13/2015 07:22 PM, Marek Szyprowski wrote: > Exynos GEM objects contains an array of pointers to the pages, which the > allocated buffer consists of. Till now the code used some hacks (like > relying on DMA-mapping internal structures or using ARM-specific > dma_to_pfn helper) to build this array. This patch fixes this by adding > proper call to dma_get_sgtable_attrs() and using the acquired scatter-list > to construct needed array. This approach is more portable (work also for > ARM64) and finally fixes the layering violation that was present in this > code. I also sent related patches to update codes of Exynos GEM object and i think this can be applied easily on my patchset or i will be able to rebase my patchset on your patch. > > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > --- > Patch is based on exynos-drm-next branch. > --- > drivers/gpu/drm/exynos/exynos_drm_gem.c | 60 +++++++++++++++++++-------------- > 1 file changed, 35 insertions(+), 25 deletions(-) > > diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c > index 29f48756e72f..e998a64a3dd0 100644 > --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c > +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c > @@ -25,6 +25,10 @@ static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem) > struct drm_device *dev = exynos_gem->base.dev; > enum dma_attr attr; > unsigned int nr_pages; > + struct sg_table sgt; > + struct scatterlist *s; > + int ret = -ENOMEM; > + int i, j; > > if (exynos_gem->dma_addr) { > DRM_DEBUG_KMS("already allocated.\n"); > @@ -56,13 +60,10 @@ static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem) > > nr_pages = exynos_gem->size >> PAGE_SHIFT; > > - if (!is_drm_iommu_supported(dev)) { > - exynos_gem->pages = drm_calloc_large(nr_pages, > - sizeof(struct page *)); > - if (!exynos_gem->pages) { > - DRM_ERROR("failed to allocate pages.\n"); > - return -ENOMEM; > - } > + exynos_gem->pages = drm_calloc_large(nr_pages, sizeof(struct page *)); > + if (!exynos_gem->pages) { > + DRM_ERROR("failed to allocate pages.\n"); > + return -ENOMEM; > } > > exynos_gem->cookie = dma_alloc_attrs(dev->dev, exynos_gem->size, > @@ -70,30 +71,40 @@ static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem) > &exynos_gem->dma_attrs); > if (!exynos_gem->cookie) { > DRM_ERROR("failed to allocate buffer.\n"); > - if (exynos_gem->pages) > - drm_free_large(exynos_gem->pages); > - return -ENOMEM; > + goto err_free; > } > > - if (exynos_gem->pages) { > - dma_addr_t start_addr; > - unsigned int i = 0; > - > - start_addr = exynos_gem->dma_addr; > - while (i < nr_pages) { > - exynos_gem->pages[i] = > - pfn_to_page(dma_to_pfn(dev->dev, start_addr)); > - start_addr += PAGE_SIZE; > - i++; > - } > - } else { > - exynos_gem->pages = exynos_gem->cookie; > + ret = dma_get_sgtable_attrs(dev->dev, &sgt, exynos_gem->cookie, > + exynos_gem->dma_addr, exynos_gem->size, > + &exynos_gem->dma_attrs); > + if (ret < 0) { > + DRM_ERROR("failed to get sgtable.\n"); > + goto err_dma_free; > + } > + > + j = 0; > + for_each_sg(sgt.sgl, s, sgt.orig_nents, i) { > + int size = s->length >> PAGE_SHIFT; > + struct page *page = sg_page(s); > + > + while (size-- > 0) > + exynos_gem->pages[j++] = page++; > } drm_prime_sg_to_page_addr_arrays() will do same operation. Thanks. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel