virtio-vdpa: support per vq dma device

This patch adds the support of per vq dma device for virito-vDPA. vDPA
parents then are allowed to use different DMA devices. This is useful
for the parents that have software or emulated virtqueues.
Reviewed-by: Eli Cohen <elic@nvidia.com>
Tested-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230119061525.75068-4-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/virtio/virtio_vdpa.c

@@ -135,6 +135,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
 {
 	struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);
 	struct vdpa_device *vdpa = vd_get_vdpa(vdev);
+	struct device *dma_dev;
 	const struct vdpa_config_ops *ops = vdpa->config;
 	struct virtio_vdpa_vq_info *info;
 	struct vdpa_callback cb;
@@ -175,9 +176,15 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
 
 	/* Create the vring */
 	align = ops->get_vq_align(vdpa);
-	vq = vring_create_virtqueue(index, max_num, align, vdev,
+
+	if (ops->get_vq_dma_dev)
+		dma_dev = ops->get_vq_dma_dev(vdpa, index);
+	else
+		dma_dev = vdpa_get_dma_dev(vdpa);
+	vq = vring_create_virtqueue_dma(index, max_num, align, vdev,
 					true, may_reduce_num, ctx,
-				    virtio_vdpa_notify, callback, name);
+					virtio_vdpa_notify, callback,
+					name, dma_dev);
 	if (!vq) {
 		err = -ENOMEM;
 		goto error_new_virtqueue;