| Message ID | 1488491084-17252-4-git-send-email-labbott@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On March 03, 2017 5:45 AM Laura Abbott wrote: > > +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(table); Free 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); > + } > + Do we need a helper, sg_copy_table(dst_table, src_table)? > + return new_table; > +} > +
On 03/03/2017 12:18 AM, Hillf Danton wrote: > > On March 03, 2017 5:45 AM Laura Abbott wrote: >> >> +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(table); > > Free 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); >> + } >> + > > Do we need a helper, sg_copy_table(dst_table, src_table)? > >> + return new_table; >> +} >> + Yes, that would probably be good since I've seen this code elsewhere. Thanks, Laura
diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c index 94a498e..ce4adac 100644 --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -799,6 +799,32 @@ 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(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) { @@ -806,13 +832,15 @@ 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,
Ion currently returns a single sg_table on each dma_map call. This is incorrect for later usage. Signed-off-by: Laura Abbott <labbott@redhat.com> --- drivers/staging/android/ion/ion.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-)