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Date:   Thu, 13 Jul 2023 09:00:07 -0700
From:   Jacob Pan <jacob.jun.pan@linux.intel.com>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     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>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Will Deacon <will@kernel.org>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "Yu, Fenghua" <fenghua.yu@intel.com>,
        "Luck, Tony" <tony.luck@intel.com>, jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH v10 2/7] iommu: Move global PASID allocation from SVA to
 core
Message-ID: <20230713090007.40ef2ac3@jacob-builder>
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        <20230712163355.3177511-3-jacob.jun.pan@linux.intel.com>
        <BN9PR11MB527619C7106BE91167B9EC118C37A@BN9PR11MB5276.namprd11.prod.outlook.com>
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Hi Kevin,

On Thu, 13 Jul 2023 07:42:01 +0000, "Tian, Kevin" <kevin.tian@intel.com>
wrote:

> > From: Jacob Pan <jacob.jun.pan@linux.intel.com>
> > Sent: Thursday, July 13, 2023 12:34 AM
> > 
> >  }
> > +
> > +ioasid_t iommu_alloc_global_pasid_dev(struct device *dev)
> > +{
> > +	int ret;
> > +
> > +	/* max_pasids == 0 means that the device does not support
> > PASID */
> > +	if (!dev->iommu->max_pasids)
> > +		return IOMMU_PASID_INVALID;
> > +
> > +	/*
> > +	 * max_pasids is set up by vendor driver based on number of
> > PASID bits
> > +	 * supported but the IDA allocation is inclusive.
> > +	 */
> > +	ret = ida_alloc_range(&iommu_global_pasid_ida,
> > IOMMU_FIRST_GLOBAL_PASID,
> > +			      dev->iommu->max_pasids - 1, GFP_KERNEL);
> > +	return ret < 0 ? IOMMU_PASID_INVALID : ret;
> > +}
> > +EXPORT_SYMBOL_GPL(iommu_alloc_global_pasid_dev);  
> 
> nit. Just call it iommu_alloc_global_pasid.

will do. it will be symmetric.

Thanks,

Jacob