diff mbox series

dma-buf: Add support for mapping buffers with DMA attributes

Message ID 20210830023911.4410-1-guangming.cao@mediatek.com
State New
Headers show
Series dma-buf: Add support for mapping buffers with DMA attributes | expand

Commit Message

guangming.cao@mediatek.com Aug. 30, 2021, 2:39 a.m. UTC
From: Guangming Cao <Guangming.Cao@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@codeaurora.org>
Signed-off-by: Sandeep Patil <sspatil@google.com>
Signed-off-by: Guangming Cao <Guangming.Cao@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(-)

Comments

Daniel Vetter Aug. 31, 2021, 12:47 p.m. UTC | #1
On Mon, Aug 30, 2021 at 10:39:11AM +0800, guangming.cao@mediatek.com wrote:
> From: Guangming Cao <Guangming.Cao@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@codeaurora.org>

> Signed-off-by: Sandeep Patil <sspatil@google.com>

> Signed-off-by: Guangming Cao <Guangming.Cao@mediatek.com>


Can you pls include the code that's going to use this here too?

At a glance all the attributes you might want to set are supposed to be
under the control of the exporter, not the importer.
-Daniel

> ---

>  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

> 


-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
diff mbox series

Patch

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;
 };
 
 /**