Date:   Mon, 30 Jan 2023 11:29:52 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Niklas Schnelle <schnelle@linux.ibm.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Wenjia Zhang <wenjia@linux.ibm.com>,
        Matthew Rosato <mjrosato@linux.ibm.com>,
        Gerd Bayer <gbayer@linux.ibm.com>,
        Pierre Morel <pmorel@linux.ibm.com>, iommu@lists.linux.dev,
        linux-s390@vger.kernel.org, borntraeger@linux.ibm.com,
        hca@linux.ibm.com, gor@linux.ibm.com,
        gerald.schaefer@linux.ibm.com, agordeev@linux.ibm.com,
        svens@linux.ibm.com, linux-kernel@vger.kernel.org,
        Julian Ruess <julianr@linux.ibm.com>
Subject: Re: [PATCH v5 5/7] iommu/dma: Allow a single FQ in addition to
 per-CPU FQs
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On Mon, Jan 30, 2023 at 03:13:22PM +0000, Robin Murphy wrote:

> Either way, the more I think about this the more I'm starting to agree that
> adding more domain types for iommu-dma policy is a step in the wrong
> direction. If I may, I'd like to fall back on the "or at least some definite
> internal flag" part of my original suggestion :)

Yes please, lets try to remove IOMMU_DOMAIN_DMA, not add more :)

At this point we should probably just sort of hackily add a ops flag
to indicate single queue and when we fixup the policy logic we can
make it a user selectable policy as well.

Jason