Re: [PATCH 8/8] iommu/vt-d: Add set_dev_pasid callback for nested domain

On 2024/1/16 1:22, Jason Gunthorpe wrote:

On Sun, Nov 26, 2023 at 10:34:28PM -0800, Yi Liu wrote:

...

+static int intel_nested_set_dev_pasid(struct iommu_domain *domain,

• 		      struct device *dev, ioasid_t pasid)
  

+{

• struct device_domain_info *info = dev_iommu_priv_get(dev);
• struct dmar_domain *dmar_domain = to_dmar_domain(domain);
• struct intel_iommu *iommu = info->iommu;
• struct dev_pasid_info *dev_pasid;
• unsigned long flags;
• int ret = 0;
• if (!pasid_supported(iommu))

• return -EOPNOTSUPP;
  

• if (iommu->agaw < dmar_domain->s2_domain->agaw)

• return -EINVAL;
  

• ret = prepare_domain_attach_device(&dmar_domain->s2_domain->domain, dev);
• if (ret)

• return ret;
  

• dev_pasid = kzalloc(sizeof(*dev_pasid), GFP_KERNEL);
• if (!dev_pasid)

• return -ENOMEM;
  

• ret = domain_attach_iommu(dmar_domain, iommu);
• if (ret)

• goto err_free;
  

• ret = intel_pasid_setup_nested(iommu, dev, pasid, dmar_domain);
• if (ret)

• goto err_detach_iommu;
  

• dev_pasid->dev = dev;
• dev_pasid->pasid = pasid;
• spin_lock_irqsave(&dmar_domain->lock, flags);
• list_add(&dev_pasid->link_domain, &dmar_domain->dev_pasids);
• spin_unlock_irqrestore(&dmar_domain->lock, flags);
• return 0;

+err_detach_iommu:

• domain_detach_iommu(dmar_domain, iommu);

+err_free:

• kfree(dev_pasid);
• return ret;

+}

This seems alot longer than I'd think it should be, why isn't it exactly the same code as the other set_dev_pasid's?

Yes. It should be. The only difference is how to configure the pasid entry.

Best regards, baolu