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Date:   Thu, 25 May 2023 08:54:48 -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>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        Joerg Roedel <joro@8bytes.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.com>,
        "dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
        "vkoul@kernel.org" <vkoul@kernel.org>,
        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>,
        "Luck, Tony" <tony.luck@intel.com>,
        "Zanussi, Tom" <tom.zanussi@intel.com>,
        "Ranganathan, Narayan" <narayan.ranganathan@intel.com>,
        jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH v7 2/4] iommu: Move global PASID allocation from SVA to
 core
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        <20230523173451.2932113-3-jacob.jun.pan@linux.intel.com>
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Hi Kevin,

On Thu, 25 May 2023 06:27:40 +0000, "Tian, Kevin" <kevin.tian@intel.com>
wrote:

> > From: Jacob Pan <jacob.jun.pan@linux.intel.com>
> > Sent: Wednesday, May 24, 2023 1:35 AM
> > 
> >  /* Allocate a PASID for the mm within range (inclusive) */
> > -static int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min,
> > ioasid_t max)
> > +static int iommu_sva_alloc_pasid(struct mm_struct *mm, struct device
> > *dev) {
> > +	ioasid_t pasid;
> >  	int ret = 0;
> > 
> > -	if (min == IOMMU_PASID_INVALID ||
> > -	    max == IOMMU_PASID_INVALID ||
> > -	    min == 0 || max < min)
> > -		return -EINVAL;
> > -
> >  	if (!arch_pgtable_dma_compat(mm))
> >  		return -EBUSY;
> > 
> >  	mutex_lock(&iommu_sva_lock);
> >  	/* Is a PASID already associated with this mm? */
> >  	if (mm_valid_pasid(mm)) {
> > -		if (mm->pasid < min || mm->pasid > max)
> > +		if (mm->pasid > dev->iommu->max_pasids)  
> 
> ">" should be ">="  
right, will do

> > +ioasid_t iommu_alloc_global_pasid_dev(struct device *dev)
> > +{
> > +	int ret;
> > +	ioasid_t max;
> > +
> > +	max = dev->iommu->max_pasids;
> > +	ret = ida_alloc_range(&iommu_global_pasid_ida,
> > IOMMU_FIRST_GLOBAL_PASID, max, GFP_KERNEL);  
> 
> max is inclusive. Here should minus one.
yeah, should be -1

> otherwise looks good to me,
> 
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>


Thanks,

Jacob