> From: Nicolin Chen <nicol...@nvidia.com> > Sent: Tuesday, October 22, 2024 8:19 AM > > Add a new ioctl for user space to do a vIOMMU allocation. It must be based > on a nesting parent HWPT, so take its refcount. > > If an IOMMU driver supports a driver-managed vIOMMU object, it must > define
why highlight 'driver-managed', implying a core-managed vIOMMU object some day? > +/** > + * struct iommu_viommu_alloc - ioctl(IOMMU_VIOMMU_ALLOC) > + * @size: sizeof(struct iommu_viommu_alloc) > + * @flags: Must be 0 > + * @type: Type of the virtual IOMMU. Must be defined in enum > iommu_viommu_type > + * @dev_id: The device's physical IOMMU will be used to back the virtual > IOMMU > + * @hwpt_id: ID of a nesting parent HWPT to associate to > + * @out_viommu_id: Output virtual IOMMU ID for the allocated object > + * > + * Allocate a virtual IOMMU object that represents the underlying physical > + * IOMMU's virtualization support. The vIOMMU object is a security-isolated > + * slice of the physical IOMMU HW that is unique to a specific VM. the object itself is a software abstraction, while a 'slice' is a set of real hw resources.
