@@ -53,11 +53,10 @@ static void sync_for_device(struct msm_gem_object *msm_obj)
struct device *dev = msm_obj->base.dev->dev;
if (get_dma_ops(dev) && IS_ENABLED(CONFIG_ARM64)) {
- dma_sync_sg_for_device(dev, msm_obj->sgt->sgl,
- msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
+ dma_sync_sgtable_for_device(dev, msm_obj->sgt,
+ DMA_BIDIRECTIONAL);
} else {
- dma_map_sg(dev, msm_obj->sgt->sgl,
- msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
+ dma_map_sgtable(dev, msm_obj->sgt, DMA_BIDIRECTIONAL);
}
}
@@ -66,11 +65,9 @@ static void sync_for_cpu(struct msm_gem_object *msm_obj)
struct device *dev = msm_obj->base.dev->dev;
if (get_dma_ops(dev) && IS_ENABLED(CONFIG_ARM64)) {
- dma_sync_sg_for_cpu(dev, msm_obj->sgt->sgl,
- msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
+ dma_sync_sgtable_for_cpu(dev, msm_obj->sgt, DMA_BIDIRECTIONAL);
} else {
- dma_unmap_sg(dev, msm_obj->sgt->sgl,
- msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
+ dma_unmap_sgtable(dev, msm_obj->sgt, DMA_BIDIRECTIONAL);
}
}
@@ -43,7 +43,7 @@ static int msm_iommu_map(struct msm_mmu *mmu, uint64_t iova,
struct msm_iommu *iommu = to_msm_iommu(mmu);
size_t ret;
- ret = iommu_map_sg(iommu->domain, iova, sgt->sgl, sgt->nents, prot);
+ ret = iommu_map_sgtable(iommu->domain, iova, sgt, prot);
WARN_ON(!ret);
return (ret == len) ? 0 : -EINVAL;
The Documentation/DMA-API-HOWTO.txt states that dma_map_sg returns the numer of the created entries in the DMA address space. However the subsequent calls to dma_sync_sg_for_{device,cpu} and dma_unmap_sg must be called with the original number of the entries passed to dma_map_sg. The sg_table->nents in turn holds the result of the dma_map_sg call as stated in include/linux/scatterlist.h. A common mistake was to ignore a result of the dma_map_sg function and don't use the sg_table->orig_nents at all. To avoid such issues, lets use common dma-mapping wrappers operating directly on the struct sg_table objects and adjust references to the nents and orig_nents respectively. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- For more information, see '[PATCH v3 00/25] DRM: fix struct sg_table nents vs. orig_nents misuse' thread: https://lkml.org/lkml/2020/5/5/187 --- drivers/gpu/drm/msm/msm_gem.c | 13 +++++-------- drivers/gpu/drm/msm/msm_iommu.c | 2 +- 2 files changed, 6 insertions(+), 9 deletions(-)