Messages in this thread | | | From | "Tian, Kevin" <> | Subject | RE: [PATCH RFC 01/11] iommu: Add pasid_bits field in struct dev_iommu | Date | Mon, 21 Mar 2022 07:01:36 +0000 |
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> From: Lu Baolu <baolu.lu@linux.intel.com> > Sent: Sunday, March 20, 2022 2:40 PM > > Use this field to save the pasid/ssid bits that a device is able to > support with its IOMMU hardware. It is a generic attribute of a device > and lifting it into the per-device dev_iommu struct makes it possible > to allocate a PASID for device without calls into the IOMMU drivers. > Any iommu driver which suports PASID related features should set this > field before features are enabled on the devices. > > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > --- > include/linux/iommu.h | 1 + > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 + > drivers/iommu/intel/iommu.c | 5 ++++- > 3 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index 6ef2df258673..36f43af0af53 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -368,6 +368,7 @@ struct dev_iommu { > struct iommu_fwspec *fwspec; > struct iommu_device *iommu_dev; > void *priv; > + unsigned int pasid_bits; > }; > > int iommu_device_register(struct iommu_device *iommu, > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > index 627a3ed5ee8f..8e262210b5ad 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -2812,6 +2812,7 @@ static int arm_smmu_dev_enable_feature(struct > device *dev, > master->iopf_enabled = true; > return 0; > case IOMMU_DEV_FEAT_SVA: > + dev->iommu->pasid_bits = master->ssid_bits; > return arm_smmu_master_enable_sva(master); > default: > return -EINVAL; > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c > index 6f7485c44a4b..c1b91bce1530 100644 > --- a/drivers/iommu/intel/iommu.c > +++ b/drivers/iommu/intel/iommu.c > @@ -4587,8 +4587,11 @@ static struct iommu_device > *intel_iommu_probe_device(struct device *dev) > if (pasid_supported(iommu)) { > int features = pci_pasid_features(pdev); > > - if (features >= 0) > + if (features >= 0) { > info->pasid_supported = features | 1; > + dev->iommu->pasid_bits = > + fls(pci_max_pasids(pdev)) - 1;
Original intel_svm_alloc_pasid() covers both PCI and non-PCI devices:
ioasid_t max_pasid = dev_is_pci(dev) ? pci_max_pasids(to_pci_dev(dev)) : intel_pasid_max_id;
though I'm not sure whether non-PCI SVA has been supported indeed, this patch implies a functional change here.
> + } > } > > if (info->ats_supported && ecap_prs(iommu->ecap) > && > -- > 2.25.1
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