dma-buf: add peer2peer flag

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@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/359286/

1 files changed, 10 insertions, 0 deletions

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
@@ -335,6 +335,14 @@ struct dma_buf {
  */
 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
 	 *
 	 * If this callback is provided the framework can avoid pinning the
@@ -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;