Date:   Mon, 20 Mar 2023 14:22:38 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     Jacob Pan <jacob.jun.pan@linux.intel.com>,
        "Luck, Tony" <tony.luck@intel.com>,
        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>,
        "dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
        "vkoul@kernel.org" <vkoul@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Will Deacon <will@kernel.org>,
        David Woodhouse <dwmw2@infradead.org>,
        "Raj, Ashok" <ashok.raj@intel.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "Yu, Fenghua" <fenghua.yu@intel.com>,
        "Jiang, Dave" <dave.jiang@intel.com>,
        "Zanussi, Tom" <tom.zanussi@intel.com>
Subject: Re: [PATCH 3/4] iommu/sva: Support reservation of global PASIDs
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On Thu, Mar 16, 2023 at 07:25:17AM +0000, Tian, Kevin wrote:
 
> I still doubt 'reserve' is the right interface to define.
> 
> for DMA domain probably yes as it's static and one-off.
> 
> but thinking louder when the same driver starts to support SIOV we
> need allocating additional PASIDs on demand which is hardly to be
> fit in a reservation interface.

Sure, it is the same thing.

It is "reserve" in the sense they are not assigned to mm structs and
not used for SVA.

Jason