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.
Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
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++;
}
+ sg_free_table(&sgt);
+
DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
(unsigned long)exynos_gem->dma_addr, exynos_gem->size);
return 0;
+
+err_dma_free:
+ dma_free_attrs(dev->dev, exynos_gem->size, exynos_gem->cookie,
+ exynos_gem->dma_addr, &exynos_gem->dma_attrs);
+err_free:
+ drm_free_large(exynos_gem->pages);
+
+ return ret;
}
static void exynos_drm_free_buf(struct exynos_drm_gem *exynos_gem)
@@ -112,8 +123,7 @@ static void exynos_drm_free_buf(struct exynos_drm_gem
*exynos_gem)
(dma_addr_t)exynos_gem->dma_addr,
&exynos_gem->dma_attrs);
- if (!is_drm_iommu_supported(dev))
- drm_free_large(exynos_gem->pages);
+ drm_free_large(exynos_gem->pages);
}
static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
--
1.9.2
