@@ -140,13 +140,12 @@ struct sg_table *dma_heap_map_dma_buf(struct dma_buf_attachment *attachment,
enum dma_data_direction direction)
{
struct dma_heaps_attachment *a = attachment->priv;
- struct sg_table *table;
-
- table = &a->table;
+ struct sg_table *table = &a->table;
+ int ret;
- if (!dma_map_sg(attachment->dev, table->sgl, table->nents,
- direction))
- table = ERR_PTR(-ENOMEM);
+ ret = dma_map_sgtable(attachment->dev, table, direction);
+ if (ret)
+ table = ERR_PTR(ret);
return table;
}
@@ -154,7 +153,7 @@ static void dma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
struct sg_table *table,
enum dma_data_direction direction)
{
- dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);
+ dma_unmap_sgtable(attachment->dev, table, direction);
}
static vm_fault_t dma_heap_vm_fault(struct vm_fault *vmf)
@@ -63,10 +63,9 @@ static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf,
GFP_KERNEL);
if (ret < 0)
goto err;
- if (!dma_map_sg(dev, sg->sgl, sg->nents, direction)) {
- ret = -EINVAL;
+ ret = dma_map_sgtable(dev, sg, direction);
+ if (ret < 0)
goto err;
- }
return sg;
err:
@@ -78,7 +77,7 @@ static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf,
static void put_sg_table(struct device *dev, struct sg_table *sg,
enum dma_data_direction direction)
{
- dma_unmap_sg(dev, sg->sgl, sg->nents, direction);
+ dma_unmap_sgtable(dev, sg, direction);
sg_free_table(sg);
kfree(sg);
}
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/dma-buf/heaps/heap-helpers.c | 13 ++++++------- drivers/dma-buf/udmabuf.c | 7 +++---- 2 files changed, 9 insertions(+), 11 deletions(-) -- 1.9.1 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel