Date:   Tue, 14 Feb 2023 13:33:52 -0800
From:   Jacob Pan <jacob.jun.pan@linux.intel.com>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Jean-Philippe Brucker <jean-philippe@linaro.org>,
        LKML <linux-kernel@vger.kernel.org>, 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>,
        Will Deacon <will@kernel.org>,
        David Woodhouse <dwmw2@infradead.org>,
        Raj Ashok <ashok.raj@intel.com>,
        "Tian, Kevin" <kevin.tian@intel.com>, Yi Liu <yi.l.liu@intel.com>,
        jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH v2 3/3] iommu: Remove ioasid infrastructure
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In-Reply-To: <Y+vLiWS3+Rp+If6U@nvidia.com>
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        <20230214064414.1038058-4-jacob.jun.pan@linux.intel.com>
        <Y+tVMRzRQbcc7Guz@myrica>
        <Y+uHSry/tpgGNr/b@nvidia.com>
        <20230214093107.323d7e76@jacob-builder>
        <Y+vLiWS3+Rp+If6U@nvidia.com>
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Hi Jason,

On Tue, 14 Feb 2023 13:57:29 -0400, Jason Gunthorpe <jgg@nvidia.com> wrote:

> On Tue, Feb 14, 2023 at 09:31:07AM -0800, Jacob Pan wrote:
> > Hi Jason,
> > 
> > On Tue, 14 Feb 2023 09:06:18 -0400, Jason Gunthorpe <jgg@nvidia.com>
> > wrote: 
> > > On Tue, Feb 14, 2023 at 09:32:33AM +0000, Jean-Philippe Brucker
> > > wrote:  
> > > > > diff --git a/include/uapi/linux/iommu.h
> > > > > b/include/uapi/linux/iommu.h index 65d8b0234f69..a95f07f0c98c
> > > > > 100644 --- a/include/uapi/linux/iommu.h
> > > > > +++ b/include/uapi/linux/iommu.h
> > > > > @@ -157,5 +157,6 @@ struct iommu_page_response {
> > > > >  	__u32	grpid;
> > > > >  	__u32	code;
> > > > >  };
> > > > > +#define IOMMU_PASID_INVALID	(-1U)    
> > > > 
> > > > Why change UAPI?    
> > > 
> > > There is no uapi, this whole file needs to be deleted too
> > >   
> > ok. another clean up.
> > 
> > As I also replied to Jean, I ran into a circular #include problem if
> > mm.h #include iommu.h, I guess I could also create another header, e.g.
> > iommu_defs.h to avoid it. any other suggestions?  
> 
> Given this header is not used, just delete things from it to resolve
> the problem?
no, sorry i didn't make it clear. I meant if we do #include <linux/iommu.h>
in sched/mm.h, then I got circular include problem.

The problem is not with include/uapi/linux/iommu.h

I could fix it by adding another header include/linux/iommu_defs.h for
#define IOMMU_PASID_INVALID	(-1U) 
But it feels like an overkill.

Thanks,

Jacob