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Subject: Re: [PATCH] vhost: introduce vDPA based backend
To:     Tiwei Bie <tiwei.bie@intel.com>
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        maxime.coquelin@redhat.com, lingshan.zhu@intel.com,
        dan.daly@intel.com, cunming.liang@intel.com, zhihong.wang@intel.com
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 <7aab2892-bb19-a06a-a6d3-9c28bc4c3400@redhat.com>
 <20200205020247.GA368700@___>
From:   Jason Wang <jasowang@redhat.com>
Message-ID: <ad1707a0-7884-1329-52c6-8139230a930c@redhat.com>
Date:   Wed, 5 Feb 2020 11:11:08 +0800
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On 2020/2/5 =E4=B8=8A=E5=8D=8810:02, Tiwei Bie wrote:
>> Before trying to do this it looks to me we need the following during t=
he
>> probe
>>
>> 1) if set_map() is not supported by the vDPA device probe the IOMMU th=
at is
>> supported by the vDPA device
>> 2) allocate IOMMU domain
>>
>> And then:
>>
>> 3) pin pages through GUP and do proper accounting
>> 4) store GPA->HPA mapping in the umem
>> 5) generate diffs of memory table and using IOMMU API to setup the dma
>> mapping in this method
>>
>> For 1), I'm not sure parent is sufficient for to doing this or need to
>> introduce new API like iommu_device in mdev.
> Agree. We may also need to introduce something like
> the iommu_device.
>

Right, this is what I plan to do in next version.

Thanks