Virtualization - Jun 2022 - [PATCH 5/6] vDPA: answer num of queue pairs = 1 to userspace when VIRTIO_NET_F_MQ == 0

On Thu, Jun 2, 2022 at 10:48 AM Zhu Lingshan <lingshan.zhu at intel.com>
wrote:
>
> If VIRTIO_NET_F_MQ == 0, the virtio device should have one queue pair,
> so when userspace querying queue pair numbers, it should return mq=1
> than zero
Spec said:

"max_virtqueue_pairs only exists if VIRTIO_NET_F_MQ is set"

So we are probably fine.

Thanks
>
> Signed-off-by: Zhu Lingshan <lingshan.zhu at intel.com>
> ---
>  drivers/vdpa/vdpa.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> index 030d96bdeed2..50a11ece603e 100644
> --- a/drivers/vdpa/vdpa.c
> +++ b/drivers/vdpa/vdpa.c
> @@ -818,9 +818,10 @@ static int vdpa_dev_net_mq_config_fill(struct
vdpa_device *vdev,
>         u16 val_u16;
>
>         if ((features & BIT_ULL(VIRTIO_NET_F_MQ)) == 0)
> -               return 0;
> +               val_u16 = 1;
> +       else
> +               val_u16 = le16_to_cpu((__force
__le16)config->max_virtqueue_pairs);
>
> -       val_u16 = le16_to_cpu(config->max_virtqueue_pairs);
>         return nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MAX_VQP, val_u16);
>  }
>
> --
> 2.31.1
>