[PATCH] dma-buf: Add support for mapping buffers with DMA attributes
guangming.cao at mediatek.com
guangming.cao at mediatek.com
Thu Aug 26 06:42:33 UTC 2021
From: Guangming Cao <Guangming.Cao at mediatek.com>
When mapping the memory represented by a dma-buf into a device's
address space, it might be desireable to map the memory with
certain DMA attributes. Thus, introduce the dma_mapping_attrs
field in the dma_buf_attachment structure so that when
the memory is mapped with dma_buf_map_attachment, it is mapped
with the desired DMA attributes.
Signed-off-by: Isaac J. Manjarres <isaacm at codeaurora.org>
Signed-off-by: Sandeep Patil <sspatil at google.com>
Signed-off-by: Guangming Cao <Guangming.Cao at mediatek.com>
---
drivers/dma-buf/heaps/cma_heap.c | 6 ++++--
drivers/dma-buf/heaps/system_heap.c | 6 ++++--
include/linux/dma-buf.h | 3 +++
3 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
index 0c05b79870f9..2c9feb3bfc3e 100644
--- a/drivers/dma-buf/heaps/cma_heap.c
+++ b/drivers/dma-buf/heaps/cma_heap.c
@@ -99,9 +99,10 @@ static struct sg_table *cma_heap_map_dma_buf(struct dma_buf_attachment *attachme
{
struct dma_heap_attachment *a = attachment->priv;
struct sg_table *table = &a->table;
+ int attrs = attachment->dma_map_attrs;
int ret;
- ret = dma_map_sgtable(attachment->dev, table, direction, 0);
+ ret = dma_map_sgtable(attachment->dev, table, direction, attrs);
if (ret)
return ERR_PTR(-ENOMEM);
a->mapped = true;
@@ -113,9 +114,10 @@ static void cma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
enum dma_data_direction direction)
{
struct dma_heap_attachment *a = attachment->priv;
+ int attrs = attachment->dma_map_attrs;
a->mapped = false;
- dma_unmap_sgtable(attachment->dev, table, direction, 0);
+ dma_unmap_sgtable(attachment->dev, table, direction, attrs);
}
static int cma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c
index 23a7e74ef966..fc7b1e02988e 100644
--- a/drivers/dma-buf/heaps/system_heap.c
+++ b/drivers/dma-buf/heaps/system_heap.c
@@ -130,9 +130,10 @@ static struct sg_table *system_heap_map_dma_buf(struct dma_buf_attachment *attac
{
struct dma_heap_attachment *a = attachment->priv;
struct sg_table *table = a->table;
+ int attrs = attachment->dma_map_attrs;
int ret;
- ret = dma_map_sgtable(attachment->dev, table, direction, 0);
+ ret = dma_map_sgtable(attachment->dev, table, direction, attrs);
if (ret)
return ERR_PTR(ret);
@@ -145,9 +146,10 @@ static void system_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
enum dma_data_direction direction)
{
struct dma_heap_attachment *a = attachment->priv;
+ int attrs = attachment->dma_map_attrs;
a->mapped = false;
- dma_unmap_sgtable(attachment->dev, table, direction, 0);
+ dma_unmap_sgtable(attachment->dev, table, direction, attrs);
}
static int system_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index efdc56b9d95f..4d650731766e 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -379,6 +379,8 @@ struct dma_buf_attach_ops {
* @importer_ops: importer operations for this attachment, if provided
* dma_buf_map/unmap_attachment() must be called with the dma_resv lock held.
* @importer_priv: importer specific attachment data.
+ * @dma_map_attrs: DMA attributes to be used when the exporter maps the buffer
+ * through dma_buf_map_attachment.
*
* This structure holds the attachment information between the dma_buf buffer
* and its user device(s). The list contains one attachment struct per device
@@ -399,6 +401,7 @@ struct dma_buf_attachment {
const struct dma_buf_attach_ops *importer_ops;
void *importer_priv;
void *priv;
+ unsigned long dma_map_attrs;
};
/**
--
2.17.1
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