vdpa: Add set/get_vq_affinity callbacks in vdpa_config_ops

This introduces set/get_vq_affinity callbacks in
vdpa_config_ops to support virtqueue affinity
management for vdpa device drivers.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230323053043.35-3-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/virtio/virtio_vdpa.c

@@ -337,6 +337,32 @@ static const char *virtio_vdpa_bus_name(struct virtio_device *vdev)
 	return dev_name(&vdpa->dev);
 }
 
+static int virtio_vdpa_set_vq_affinity(struct virtqueue *vq,
+				       const struct cpumask *cpu_mask)
+{
+	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq->vdev);
+	struct vdpa_device *vdpa = vd_dev->vdpa;
+	const struct vdpa_config_ops *ops = vdpa->config;
+	unsigned int index = vq->index;
+
+	if (ops->set_vq_affinity)
+		return ops->set_vq_affinity(vdpa, index, cpu_mask);
+
+	return 0;
+}
+
+static const struct cpumask *
+virtio_vdpa_get_vq_affinity(struct virtio_device *vdev, int index)
+{
+	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	const struct vdpa_config_ops *ops = vdpa->config;
+
+	if (ops->get_vq_affinity)
+		return ops->get_vq_affinity(vdpa, index);
+
+	return NULL;
+}
+
 static const struct virtio_config_ops virtio_vdpa_config_ops = {
 	.get		= virtio_vdpa_get,
 	.set		= virtio_vdpa_set,
@@ -349,6 +375,8 @@ static const struct virtio_config_ops virtio_vdpa_config_ops = {
 	.get_features	= virtio_vdpa_get_features,
 	.finalize_features = virtio_vdpa_finalize_features,
 	.bus_name	= virtio_vdpa_bus_name,
+	.set_vq_affinity = virtio_vdpa_set_vq_affinity,
+	.get_vq_affinity = virtio_vdpa_get_vq_affinity,
 };
 
 static void virtio_vdpa_release_dev(struct device *_d)

include/linux/vdpa.h

@@ -250,6 +250,15 @@ struct vdpa_map_file {
  *				@vdev: vdpa device
  *				Returns the iova range supported by
  *				the device.
+ * @set_vq_affinity:		Set the affinity of virtqueue (optional)
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				@cpu_mask: the affinity mask
+ *				Returns integer: success (0) or error (< 0)
+ * @get_vq_affinity:		Get the affinity of virtqueue (optional)
+ *				@vdev: vdpa device
+ *				@idx: virtqueue index
+ *				Returns the affinity mask
  * @set_group_asid:		Set address space identifier for a
  *				virtqueue group (optional)
  *				@vdev: vdpa device
@@ -340,6 +349,10 @@ struct vdpa_config_ops {
 			   const void *buf, unsigned int len);
 	u32 (*get_generation)(struct vdpa_device *vdev);
 	struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
+	int (*set_vq_affinity)(struct vdpa_device *vdev, u16 idx,
+			       const struct cpumask *cpu_mask);
+	const struct cpumask *(*get_vq_affinity)(struct vdpa_device *vdev,
+						 u16 idx);
 
 	/* DMA ops */
 	int (*set_map)(struct vdpa_device *vdev, unsigned int asid,