Re: [PATCH 0/5] iommu: Some IOVA code reorganisation

Robin Murphy
2021-11-16T14:26:02Z

On 2021-11-16 14:21, John Garry wrote:
> 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?

Hey John - as it happens I started hacking on that in earnest about half
an hour ago, aiming to get something out later this week.

Cheers,
Robin.

> 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