Re: [PATCH] mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK

[Michael S. Tsirkin]

On Mon, Jul 03, 2023 at 04:25:14PM +0200, Eugenio Pérez wrote:
> Offer this backend feature as mlx5 is compatible with it. It allows it
> to do live migration with CVQ, dynamically switching between passthrough
> and shadow virtqueue.
> 
> Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>

Same comment.

> ---
>  drivers/vdpa/mlx5/net/mlx5_vnet.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 9138ef2fb2c8..5f309a16b9dc 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -7,6 +7,7 @@
>  #include <uapi/linux/virtio_net.h>
>  #include <uapi/linux/virtio_ids.h>
>  #include <uapi/linux/vdpa.h>
> +#include <uapi/linux/vhost_types.h>
>  #include <linux/virtio_config.h>
>  #include <linux/auxiliary_bus.h>
>  #include <linux/mlx5/cq.h>
> @@ -2499,6 +2500,11 @@ static void unregister_link_notifier(struct mlx5_vdpa_net *ndev)
>  		flush_workqueue(ndev->mvdev.wq);
>  }
>  
> +static u64 mlx5_vdpa_get_backend_features(const struct vdpa_device *vdpa)
> +{
> +	return BIT_ULL(VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK);
> +}
> +
>  static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features)
>  {
>  	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
> @@ -3140,6 +3146,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = {
>  	.get_vq_align = mlx5_vdpa_get_vq_align,
>  	.get_vq_group = mlx5_vdpa_get_vq_group,
>  	.get_device_features = mlx5_vdpa_get_device_features,
> +	.get_backend_features = mlx5_vdpa_get_backend_features,
>  	.set_driver_features = mlx5_vdpa_set_driver_features,
>  	.get_driver_features = mlx5_vdpa_get_driver_features,
>  	.set_config_cb = mlx5_vdpa_set_config_cb,
> -- 
> 2.39.3