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Date:   Thu, 12 Jan 2023 09:26:10 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Baolu Lu <baolu.lu@linux.intel.com>
Cc:     Bjorn Helgaas <bhelgaas@google.com>,
        Joerg Roedel <jroedel@suse.de>,
        Christian =?utf-8?B?S8O2bmln?= <christian.koenig@amd.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Vasant Hegde <vasant.hegde@amd.com>,
        Tony Zhu <tony.zhu@intel.com>, linux-pci@vger.kernel.org,
        iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
        Matt Fagnani <matt.fagnani@bell.net>
Subject: Re: [PATCH 1/1] PCI: Add translated request only opt-in for
 pci_enable_pasid()
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 <78a15f05-29d7-9dd3-175a-3915e7357c11@linux.intel.com>
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On Thu, Jan 12, 2023 at 09:25:25PM +0800, Baolu Lu wrote:
> On 2023/1/12 20:38, Jason Gunthorpe wrote:
> > On Thu, Jan 12, 2023 at 04:46:29PM +0800, Lu Baolu wrote:
> > 
> > > -int pci_enable_pasid(struct pci_dev *pdev, int features);
> > > +int pci_enable_pasid(struct pci_dev *pdev, int features, bool
> > > transled_only);
> > 
> > Please use a named flag so we can grep for it..
> 
> Sure. What do you think of this naming?
> 
> + * @flags: device-specific flags
> + *   - PCI_PASID_TRANSLED_REQ_ONLY: The PCI device only issues PASID
> + *                                  memory requests of translated type.

Yes

> > Discuss in the commit message that this is a temporary step and that
> > pci_enable_pasid() needs to be moved to the drivers
> 
> I will add below in commit message:
> 
> At present, it is a common practice to enable/disable PCI PASID in the
> iommu drivers. Considering that the device driver knows more about the
> specific device, we will follow up by moving pci_enable_pasid() into
> the specific device drivers.

Yes

Jason