Re: [PATCH v9 00/14] iommufd: Add vIOMMU infrastructure (Part-3: vEVENTQ)

[Jason Gunthorpe <jgg@nvidia.com>]

On Tue, Mar 11, 2025 at 12:44:18PM -0700, Nicolin Chen wrote:
> As the vIOMMU infrastructure series part-3, this introduces a new vEVENTQ
> object. The existing FAULT object provides a nice notification pathway to
> the user space with a queue already, so let vEVENTQ reuse that.
> 
> Mimicing the HWPT structure, add a common EVENTQ structure to support its
> derivatives: IOMMUFD_OBJ_FAULT (existing) and IOMMUFD_OBJ_VEVENTQ (new).
> 
> An IOMMUFD_CMD_VEVENTQ_ALLOC is introduced to allocate vEVENTQ object for
> vIOMMUs. One vIOMMU can have multiple vEVENTQs in different types but can
> not support multiple vEVENTQs in the same type.
> 
> The forwarding part is fairly simple but might need to replace a physical
> device ID with a virtual device ID in a driver-level event data structure.
> So, this also adds some helpers for drivers to use.
> 
> As usual, this series comes with the selftest coverage for this new ioctl
> and with a real world use case in the ARM SMMUv3 driver.

> Nicolin Chen (14):
>   iommufd/fault: Move two fault functions out of the header
>   iommufd/fault: Add an iommufd_fault_init() helper
>   iommufd: Abstract an iommufd_eventq from iommufd_fault
>   iommufd: Rename fault.c to eventq.c
>   iommufd: Add IOMMUFD_OBJ_VEVENTQ and IOMMUFD_CMD_VEVENTQ_ALLOC
>   iommufd/viommu: Add iommufd_viommu_get_vdev_id helper
>   iommufd/viommu: Add iommufd_viommu_report_event helper
>   iommufd/selftest: Require vdev_id when attaching to a nested domain
>   iommufd/selftest: Add IOMMU_TEST_OP_TRIGGER_VEVENT for vEVENTQ
>     coverage
>   iommufd/selftest: Add IOMMU_VEVENTQ_ALLOC test coverage
>   Documentation: userspace-api: iommufd: Update FAULT and VEVENTQ
>   iommu/arm-smmu-v3: Introduce struct arm_smmu_vmaster
>   iommu/arm-smmu-v3: Report events that belong to devices attached to
>     vIOMMU
>   iommu/arm-smmu-v3: Set MEV bit in nested STE for DoS mitigations

Applied, thanks

Jason