From 17fd283f3870dd63c91c99591aab14e21799c119 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Mon, 3 Apr 2017 11:57:47 -0700 Subject: [PATCH] staging: android: ion: Duplicate sg_table Ion currently returns a single sg_table on each dma_map call. This is incorrect for later usage. Signed-off-by: Laura Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/ion/ion.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c index c2adfe1ea2b9..7dcb8a94de8a 100644 --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -800,6 +800,32 @@ static void ion_buffer_sync_for_device(struct ion_buffer *buffer, struct device *dev, enum dma_data_direction direction); +static struct sg_table *dup_sg_table(struct sg_table *table) +{ + struct sg_table *new_table; + int ret, i; + struct scatterlist *sg, *new_sg; + + new_table = kzalloc(sizeof(*new_table), GFP_KERNEL); + if (!new_table) + return ERR_PTR(-ENOMEM); + + ret = sg_alloc_table(new_table, table->nents, GFP_KERNEL); + if (ret) { + kfree(new_table); + return ERR_PTR(-ENOMEM); + } + + new_sg = new_table->sgl; + for_each_sg(table->sgl, sg, table->nents, i) { + memcpy(new_sg, sg, sizeof(*sg)); + sg->dma_address = 0; + new_sg = sg_next(new_sg); + } + + return new_table; +} + static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment, enum dma_data_direction direction) { @@ -807,13 +833,15 @@ static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment, struct ion_buffer *buffer = dmabuf->priv; ion_buffer_sync_for_device(buffer, attachment->dev, direction); - return buffer->sg_table; + return dup_sg_table(buffer->sg_table); } static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment, struct sg_table *table, enum dma_data_direction direction) { + sg_free_table(table); + kfree(table); } void ion_pages_sync_for_device(struct device *dev, struct page *page, -- 2.11.0