[PATCH 1/6] dma-buf: add peer2peer flag

[Daniel Vetter]

On Mon, Mar 30, 2020 at 03:55:31PM +0200, Christian König wrote:
> Add a peer2peer flag noting that the importer can deal with device
> resources which are not backed by pages.
> 
> Signed-off-by: Christian König <christian.koenig at amd.com>

On the series:

Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
>  drivers/dma-buf/dma-buf.c |  2 ++
>  include/linux/dma-buf.h   | 10 ++++++++++
>  2 files changed, 12 insertions(+)
> 
> diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
> index ccc9eda1bc28..570c923023e6 100644
> --- a/drivers/dma-buf/dma-buf.c
> +++ b/drivers/dma-buf/dma-buf.c
> @@ -690,6 +690,8 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev,
>  
>  	attach->dev = dev;
>  	attach->dmabuf = dmabuf;
> +	if (importer_ops)
> +		attach->peer2peer = importer_ops->allow_peer2peer;
>  	attach->importer_ops = importer_ops;
>  	attach->importer_priv = importer_priv;
>  
> diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
> index 1ade486fc2bb..82e0a4a64601 100644
> --- a/include/linux/dma-buf.h
> +++ b/include/linux/dma-buf.h
> @@ -334,6 +334,14 @@ struct dma_buf {
>   * Attachment operations implemented by the importer.
>   */
>  struct dma_buf_attach_ops {
> +	/**
> +	 * @allow_peer2peer:
> +	 *
> +	 * If this is set to true the importer must be able to handle peer
> +	 * resources without struct pages.
> +	 */
> +	bool allow_peer2peer;
> +
>  	/**
>  	 * @move_notify
>  	 *
> @@ -362,6 +370,7 @@ struct dma_buf_attach_ops {
>   * @node: list of dma_buf_attachment, protected by dma_resv lock of the dmabuf.
>   * @sgt: cached mapping.
>   * @dir: direction of cached mapping.
> + * @peer2peer: true if the importer can handle peer resources without pages.
>   * @priv: exporter specific attachment data.
>   * @importer_ops: importer operations for this attachment, if provided
>   * dma_buf_map/unmap_attachment() must be called with the dma_resv lock held.
> @@ -382,6 +391,7 @@ struct dma_buf_attachment {
>  	struct list_head node;
>  	struct sg_table *sgt;
>  	enum dma_data_direction dir;
> +	bool peer2peer;
>  	const struct dma_buf_attach_ops *importer_ops;
>  	void *importer_priv;
>  	void *priv;
> -- 
> 2.17.1
> 

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