RE: [PATCH 3/5] virtio-vdpa: support per vq dma device

[Eli Cohen]

> From: Jason Wang <jasowang@xxxxxxxxxx>
> Sent: Wednesday, 11 January 2023 8:28
> To: mst@xxxxxxxxxx; jasowang@xxxxxxxxxx
> Cc: Eli Cohen <elic@xxxxxxxxxx>; gdawar@xxxxxxx;
> virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> tanuj.kamde@xxxxxxx
> Subject: [PATCH 3/5] 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.
> 
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
Reviewed-by: Eli Cohen <elic@xxxxxxxxxx>
Tested-by: <elic@xxxxxxxxxx>
> ---
>  drivers/virtio/virtio_vdpa.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
> index 9670cc79371d..d7f5af62ddaa 100644
> --- a/drivers/virtio/virtio_vdpa.c
> +++ b/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,
> -				    true, may_reduce_num, ctx,
> -				    virtio_vdpa_notify, callback, name);
> +
> +	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, dma_dev);
>  	if (!vq) {
>  		err = -ENOMEM;
>  		goto error_new_virtqueue;
> --
> 2.25.1