Date:   Tue, 14 Feb 2023 10:56:02 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        Joerg Roedel <joro@8bytes.org>,
        Jean-Philippe Brucker <jean-philippe@linaro.com>,
        Robin Murphy <robin.murphy@arm.com>,
        David Woodhouse <dwmw2@infradead.org>,
        "Raj, Ashok" <ashok.raj@intel.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>
Subject: Re: [PATCH 2/2] iommu/ioasid: Remove custom IOASID allocator
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On Tue, Feb 14, 2023 at 06:26:25AM +0000, Tian, Kevin wrote:
> > From: Jason Gunthorpe <jgg@nvidia.com>
> > Sent: Tuesday, February 14, 2023 7:46 AM
> > 
> > > > So if a cgroup comes it is just a matter of putting charges in the
> > > > right place which is auditable by looking at calls to attach pasid
> > > > functions.
> > > shouldn't we charge cg during allocation? Or it might be too early for
> > > iommufd so we have to wait  until attach?
> > 
> > We need to sort this all out. I would expect that iommufd will have an
> > allocation API.
> > 
> 
> yes. 
> 
> btw presumably iommu_global_pasid_ida should be move to iommu.c
> since it will be used beyond sva.

Yeah, maybe, I'd think about moving it when we get patches to use it
more than SVA.

Jason