Subject: Re: [PATCH 0/5] iommu: Some IOVA code reorganisation
To:     Will Deacon <will@kernel.org>, <robin.murphy@arm.com>
CC:     <joro@8bytes.org>, <mst@redhat.com>, <jasowang@redhat.com>,
        <xieyongji@bytedance.com>, <linux-kernel@vger.kernel.org>,
        <iommu@lists.linux-foundation.org>,
        <virtualization@lists.linux-foundation.org>, <linuxarm@huawei.com>,
        <thunder.leizhen@huawei.com>, <baolu.lu@linux.intel.com>
References: <1632477717-5254-1-git-send-email-john.garry@huawei.com>
 <20211004114418.GC27373@willie-the-truck>
From:   John Garry <john.garry@huawei.com>
Message-ID: <cdb502c5-4896-385b-8872-f4f20e9c7e34@huawei.com>
Date:   Tue, 16 Nov 2021 14:21:09 +0000
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On 04/10/2021 12:44, Will Deacon wrote:
> On Fri, Sep 24, 2021 at 06:01:52PM +0800, John Garry wrote:
>> The IOVA domain structure is a bit overloaded, holding:
>> - IOVA tree management
>> - FQ control
>> - IOVA rcache memories
>>
>> Indeed only a couple of IOVA users use the rcache, and only dma-iommu.c
>> uses the FQ feature.
>>
>> This series separates out that structure. In addition, it moves the FQ
>> code into dma-iommu.c . This is not strictly necessary, but it does make
>> it easier for the FQ domain lookup the rcache domain.
>>
>> The rcache code stays where it is, as it may be reworked in future, so
>> there is not much point in relocating and then discarding.
>>
>> This topic was initially discussed and suggested (I think) by Robin here:
>> https://lore.kernel.org/linux-iommu/1d06eda1-9961-d023-f5e7-fe87e768f067@arm.com/
> It would be useful to have Robin's Ack on patches 2-4. The implementation
> looks straightforward to me, but the thread above isn't very clear about
> what is being suggested.

Hi Robin,

Just wondering if you had made any progress on your FQ code rework or 
your own re-org?

I wasn't planning on progressing 
https://lore.kernel.org/linux-iommu/1626259003-201303-1-git-send-email-john.garry@huawei.com/ 
until this is done first (and that is still a big issue), even though 
not strictly necessary.

Thanks,
John