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Subject: Re: [PATCH 07/21] vdpa: multiple address spaces support
To:     Eli Cohen <elic@nvidia.com>
Cc:     mst@redhat.com, eperezma@redhat.com, kvm@vger.kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
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        lingshan.zhu@intel.com, rob.miller@broadcom.com,
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References: <20201216064818.48239-1-jasowang@redhat.com>
 <20201216064818.48239-8-jasowang@redhat.com>
 <20201229072832.GA195479@mtl-vdi-166.wap.labs.mlnx>
From:   Jason Wang <jasowang@redhat.com>
Message-ID: <bbd05848-3376-3a35-8914-16f19c74f373@redhat.com>
Date:   Wed, 30 Dec 2020 12:00:00 +0800
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On 2020/12/29 下午3:28, Eli Cohen wrote:
>> @@ -43,6 +43,8 @@ struct vdpa_vq_state {
>>    * @index: device index
>>    * @features_valid: were features initialized? for legacy guests
>>    * @nvqs: the number of virtqueues
>> + * @ngroups: the number of virtqueue groups
>> + * @nas: the number of address spaces
> I am not sure these can be categorised as part of the state of the VQ.
> It's more of a property so maybe we can have a callback to get the
> properties of the VQ?
>
> Moreover, I think they should be handled in the hardware drivers to
> return 1 for both ngroups and nas.


We can, but those are static attributes that is not expected to be 
changed by the driver.

Introduce callbacks for those static stuffs does not give us any advantage.

For group id and notification area, since we don't have a abstract of 
vdpa_virtqueue. The only choice is to introduce callbacks for them.

Maybe it's time to introduce vdpa_virtqueue.

Thanks