RE: [PATCH v2 6/7] iommufd/selftest: Make selftest create a more complete mock device

From: Jason Gunthorpe jgg@nvidia.com Sent: Thursday, February 23, 2023 5:03 AM

iommufd wants to use more infrastructure, like the iommu_group, that the mock device does not support. Create a more complete mock device that can go through the whole cycle of ownership, blocking domain, and has an iommu_group.

this is a nice move! Presumable with a real struct device we can further extend the mock device to test nested, pasid attach/alloc, etc. in the future.

• /*

• * The iommu core has no way to associate a single device with an
  

iommu

• * driver (heck currently it can't even support two iommu_drivers
  

• * registering). Hack it together with an open coded dev_iommu_get().
  

• * Notice that the normal notifier triggered iommu release process
  

also

• * does not work here because this bus is not in iommu_buses.
  

• */
  

• mdev->dev.iommu = kzalloc(sizeof(*dev_iommu), GFP_KERNEL);
• if (!mdev->dev.iommu) {

• rc = -ENOMEM;
  

• goto err_group;
  

• }
• mutex_init(&mdev->dev.iommu->lock);
• mdev->dev.iommu->iommu_dev = &mock_iommu_device;

I understand how this hack works but didn't get why in this case dev_iommu_get() cannot be reused...

but this is minor.

Reviewed-by: Kevin Tian kevin.tian@intel.com