On Wed, Mar 08, 2023 at 11:53:54PM -0800, 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. So before set up nested translation, userspace > needs to know the hardware iommu information. 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. > > This series reports the iommu hardware information for a given iommufd_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_DEVICE_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 picture is available in [1] as well. Other than the small notes this looks pretty good to me Jason
