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Subject: Re: [PATCH v3 01/12] iommu: Introduce dirty log tracking framework
To:     Keqian Zhu <zhukeqian1@huawei.com>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        iommu@lists.linux-foundation.org,
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        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Tian Kevin <kevin.tian@intel.com>
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From:   Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <4e7ae083-08f5-b273-f873-21a2960ea68a@linux.intel.com>
Date:   Mon, 19 Apr 2021 09:59:36 +0800
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Hi Keqian,

On 4/16/21 5:07 PM, Keqian Zhu wrote:
>> I am worrying about having two sets of APIs for single purpose. From
>> vendor iommu driver's point of view, this feature is per device. Hence,
>> it still needs to do the same thing.
> Yes, we can unify the granule of feature reporting and status management.
> 
> The basic granule of dirty tracking is iommu_domain, I think it's very reasonable. We need an
> interface to report the feature of iommu_domain, then the logic is much more clear.
> 
> Every time we add new device or remove device from the domain, we should update the feature (e.g.,
> maintain a counter of unsupported devices).

Yes. This looks cleaner.

> 
> What do you think about this idea?
> 
> Thanks,
> Keqian

Best regards,
baolu