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Date:   Fri, 2 Sep 2022 09:48:44 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Baolu Lu <baolu.lu@linux.intel.com>
Cc:     Joerg Roedel <joro@8bytes.org>,
        Christoph Hellwig <hch@infradead.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.com>,
        Dave Jiang <dave.jiang@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Vinod Koul <vkoul@kernel.org>,
        Eric Auger <eric.auger@redhat.com>,
        Liu Yi L <yi.l.liu@intel.com>,
        Jacob jun Pan <jacob.jun.pan@intel.com>,
        Zhangfei Gao <zhangfei.gao@linaro.org>,
        Zhu Tony <tony.zhu@intel.com>, iommu@lists.linux.dev,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v12 07/17] iommu: Try to allocate blocking domain when
 probing device
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On Thu, Sep 01, 2022 at 06:44:10PM +0800, Baolu Lu wrote:
> On 2022/8/31 22:10, Jason Gunthorpe wrote:
> > On Wed, Aug 31, 2022 at 09:49:44AM +0800, Baolu Lu wrote:
> > > > Maybe all of this is just the good reason to go to a simple
> > > > device->ops->remove_dev_pasid() callback and forget about blocking
> > > > domain here.
> > > 
> > > Do you mean rolling back to what we did in v10?
> > 
> > Yeah, but it shouldn't be a domain_op, removing a pasid is a device op
> > 
> > Just
> > 
> > remove_dev_pasid(struct device *dev, ioasid_t pasid)
> 
> It's clear now. Thanks!
> 
> How about below iommu_attach/detach_device_pasid() code?

I think this is probably the right thing

> By the way, how about naming it "block_dev_pasid(dev, pasid)"?

set/remove is a better pairing that set/block

Jason