Subject: Re: [PATCH 2/7] vDPA/ifcvf: introduce new helpers to set config vector and vq vectors

From: "Michael S. Tsirkin" <[email-masked]>
Date: Mon, 10 Jan 2022 01:15:53 -0500

On Mon, Jan 10, 2022 at 01:18:46PM +0800, Zhu Lingshan wrote:
> This commit introduces new helpers to set config vector
> and vq vectors in virtio common config space.
> 
> Signed-off-by: Zhu Lingshan <[email-masked]>
> ---
>  drivers/vdpa/ifcvf/ifcvf_base.c | 30 ++++++++++++++++++++++++++++++
>  drivers/vdpa/ifcvf/ifcvf_base.h |  2 ++
>  2 files changed, 32 insertions(+)
> 
> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c b/drivers/vdpa/ifcvf/ifcvf_base.c
> index 0b5df4cfaf06..696a41560eaa 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_base.c
> +++ b/drivers/vdpa/ifcvf/ifcvf_base.c
> @@ -15,6 +15,36 @@ struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw)
>  	return container_of(hw, struct ifcvf_adapter, vf);
>  }
>  
> +int ifcvf_set_vq_vector(struct ifcvf_hw *hw, u16 qid, int vector)
> +{
> +	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
> +	struct ifcvf_adapter *ifcvf = vf_to_adapter(hw);
> +
> +	ifc_iowrite16(qid, &cfg->queue_select);
> +	ifc_iowrite16(vector, &cfg->queue_msix_vector);
> +	if (ifc_ioread16(&cfg->queue_msix_vector) == VIRTIO_MSI_NO_VECTOR) {
> +		IFCVF_ERR(ifcvf->pdev, "No msix vector for queue %u\n", qid);
> +			return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +int ifcvf_set_config_vector(struct ifcvf_hw *hw, int vector)
> +{
> +	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
> +	struct ifcvf_adapter *ifcvf = vf_to_adapter(hw);
> +
> +	cfg = hw->common_cfg;
> +	ifc_iowrite16(vector,  &cfg->msix_config);
> +	if (ifc_ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFCVF_ERR(ifcvf->pdev, "No msix vector for device config\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +

The messages are confusing. Something like "unable to set" would be
clearer. And maybe supply the info which vector and which vq to set?

>  static void __iomem *get_cap_addr(struct ifcvf_hw *hw,
>  				  struct virtio_pci_cap *cap)
>  {
> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
> index c924a7673afb..1d5431040d7d 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_base.h
> +++ b/drivers/vdpa/ifcvf/ifcvf_base.h
> @@ -157,4 +157,6 @@ u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid);
>  int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num);
>  struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw);
>  int ifcvf_probed_virtio_net(struct ifcvf_hw *hw);
> +int ifcvf_set_vq_vector(struct ifcvf_hw *hw, u16 qid, int vector);
> +int ifcvf_set_config_vector(struct ifcvf_hw *hw, int vector);
>  #endif /* _IFCVF_H_ */
> -- 
> 2.27.0