On Fri, Aug 11, 2023 at 12:14:57AM -0700, Yi Liu wrote: > iommufd gives userspace the capability to manipulate iommu subsytem. > e.g. DMA map/unmap etc. In the near future, it will support iommu nested > translation. Different platform vendors have different implementation for > the nested translation. For example, Intel VT-d supports using guest I/O > page table as the stage-1 translation table. This requires guest I/O page > table be compatible with hardware IOMMU. So before set up nested translation, > userspace needs to know the hardware iommu information to understand the > nested translation requirements. > > This series reports the iommu hardware information for a given device > which has been bound to iommufd. It is preparation work for userspace to > allocate hwpt for given device. Like the nested translation support[1]. > > This series introduces an iommu op to report the iommu hardware info, > and an ioctl IOMMU_GET_HW_INFO is added to report such hardware info to > user. enum iommu_hw_info_type is defined to differentiate the iommu hardware > info reported to user hence user can decode them. This series only adds the > framework for iommu hw info reporting, the complete reporting path needs vendor > specific definition and driver support. The full code is available in [1] > as well. > > [1] https://github.com/yiliu1765/iommufd/tree/wip/iommufd_nesting_08112023-yi > (only the hw_info report path is the latest, other parts is wip) I made the changes I noted and pull these plus the single vt-d patch into iommufd for-next Let me know if it is not OK and we can back it out Thanks, Jason