[PATCH v5 21/38] drm: rockchip: use common helper for a scatterlist contiguity check

From: Marek Szyprowski
Date: Wed May 13 2020 - 09:35:00 EST


Use common helper for checking the contiguity of the imported dma-buf.

Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
For more information, see '[PATCH v5 00/38] DRM: fix struct sg_table nents
vs. orig_nents misuse' thread:
https://lore.kernel.org/linux-iommu/20200513132114.6046-1-m.szyprowski@xxxxxxxxxxx/T/
---
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 19 +------------------
1 file changed, 1 insertion(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
index 0d18846..21f8cb2 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
@@ -460,23 +460,6 @@ struct sg_table *rockchip_gem_prime_get_sg_table(struct drm_gem_object *obj)
return sgt;
}

-static unsigned long rockchip_sg_get_contiguous_size(struct sg_table *sgt,
- int count)
-{
- struct scatterlist *s;
- dma_addr_t expected = sg_dma_address(sgt->sgl);
- unsigned int i;
- unsigned long size = 0;
-
- for_each_sg(sgt->sgl, s, count, i) {
- if (sg_dma_address(s) != expected)
- break;
- expected = sg_dma_address(s) + sg_dma_len(s);
- size += sg_dma_len(s);
- }
- return size;
-}
-
static int
rockchip_gem_iommu_map_sg(struct drm_device *drm,
struct dma_buf_attachment *attach,
@@ -498,7 +481,7 @@ static unsigned long rockchip_sg_get_contiguous_size(struct sg_table *sgt,
if (!count)
return -EINVAL;

- if (rockchip_sg_get_contiguous_size(sg, count) < attach->dmabuf->size) {
+ if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) {
DRM_ERROR("failed to map sg_table to contiguous linear address.\n");
dma_unmap_sg(drm->dev, sg->sgl, sg->nents,
DMA_BIDIRECTIONAL);
--
1.9.1