[PATCH v4 1/9] vdpa: add bind_mm/unbind_mm callbacks

[Stefano Garzarella <sgarzare@redhat.com>]

These new optional callbacks is used to bind/unbind the device to
a specific address space so the vDPA framework can use VA when
these callbacks are implemented.

Suggested-by: Jason Wang <jasowang@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---

Notes:
    v2:
    - removed `struct task_struct *owner` param (unused for now, maybe
      useful to support cgroups) [Jason]
    - add unbind_mm callback [Jason]

 include/linux/vdpa.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 43f59ef10cc9..369c21394284 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -290,6 +290,14 @@ struct vdpa_map_file {
  *				@vdev: vdpa device
  *				@idx: virtqueue index
  *				Returns pointer to structure device or error (NULL)
+ * @bind_mm:			Bind the device to a specific address space
+ *				so the vDPA framework can use VA when this
+ *				callback is implemented. (optional)
+ *				@vdev: vdpa device
+ *				@mm: address space to bind
+ * @unbind_mm:			Unbind the device from the address space
+ *				bound using the bind_mm callback. (optional)
+ *				@vdev: vdpa device
  * @free:			Free resources that belongs to vDPA (optional)
  *				@vdev: vdpa device
  */
@@ -351,6 +359,8 @@ struct vdpa_config_ops {
 	int (*set_group_asid)(struct vdpa_device *vdev, unsigned int group,
 			      unsigned int asid);
 	struct device *(*get_vq_dma_dev)(struct vdpa_device *vdev, u16 idx);
+	int (*bind_mm)(struct vdpa_device *vdev, struct mm_struct *mm);
+	void (*unbind_mm)(struct vdpa_device *vdev);
 
 	/* Free device resources */
 	void (*free)(struct vdpa_device *vdev);
-- 
2.39.2