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To:     Jacob Pan <jacob.jun.pan@linux.intel.com>,
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        "Zanussi, Tom" <tom.zanussi@intel.com>
Subject: RE: [PATCH v4 3/7] iommu: Support allocation of global PASIDs outside
 SVA
Thread-Topic: [PATCH v4 3/7] iommu: Support allocation of global PASIDs
 outside SVA
Thread-Index: AQHZaXsLtMsZXOkKfUCVQhgiFuDaKa8lvRiA
Date:   Tue, 11 Apr 2023 08:02:55 +0000
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References: <20230407180554.2784285-1-jacob.jun.pan@linux.intel.com>
 <20230407180554.2784285-4-jacob.jun.pan@linux.intel.com>
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> From: Jacob Pan <jacob.jun.pan@linux.intel.com>
> Sent: Saturday, April 8, 2023 2:06 AM
> @@ -28,8 +26,8 @@ static int iommu_sva_alloc_pasid(struct mm_struct
> *mm, ioasid_t min, ioasid_t ma
>  		goto out;
>  	}
>=20
> -	ret =3D ida_alloc_range(&iommu_global_pasid_ida, min, max,
> GFP_KERNEL);
> -	if (ret < min)
> +	ret =3D iommu_alloc_global_pasid(min, max);

I wonder whether this can take a device pointer so dev->iommu->max_pasids
is enforced inside the alloc function.

and do we even need the min/max parameters? With special pasids reserved
then what driver needs is just to get a free pasid from the global space wi=
thin
dev->iommu->max_pasids constraint...

iommu_sva_alloc_pasid() can be reworked to avoid min/max by taking a=20
device pointer too.