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Date:   Wed, 25 Aug 2021 07:32:37 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Jason Gunthorpe <jgg@ziepe.ca>
Cc:     Christoph Hellwig <hch@lst.de>,
        Alex Williamson <alex.williamson@redhat.com>,
        Diana Craciun <diana.craciun@oss.nxp.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Kirti Wankhede <kwankhede@nvidia.com>,
        Eric Auger <eric.auger@redhat.com>, kvm@vger.kernel.org
Subject: Re: [PATCH 07/14] vfio: simplify iommu group allocation for
 mediated devices
Message-ID: <20210825053237.GB26806@lst.de>
References: <20210824144649.1488190-1-hch@lst.de> <20210824144649.1488190-8-hch@lst.de> <20210825001916.GN543798@ziepe.ca>
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On Tue, Aug 24, 2021 at 09:19:16PM -0300, Jason Gunthorpe wrote:
> The mechanism looks fine, but I think the core code is much clearer if
> the name is not 'mediated' but 'sw_iommu' or something that implies
> the group is running with a software page table. mediated has become
> so overloaded in this code.

I thought that was sort of the definition of mediated - there needs to
ben entify that "mediates" access so that a user of this interface
can't trigger undmediated DMA to arbitrary addresses.  My other choice
that I used for a while was "virtual".  sw_iommu sounds a little clumsy.

I guess either way we need some documentation describing it along the
above lines.