> From: Nicolin Chen <nicolinc@xxxxxxxxxx> > Sent: Friday, March 17, 2023 12:02 PM > > On Fri, Mar 17, 2023 at 03:02:26AM +0000, Tian, Kevin wrote: > > > > +/** > > > + * struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC) > > > + * @size: sizeof(struct iommu_hwpt_alloc) > > > + * @flags: Must be 0 > > > + * @dev_id: The device to allocate this HWPT for > > > + * @pt_id: The IOAS to connect this HWPT to > > > + * @out_hwpt_id: The ID of the new HWPT > > > + * @__reserved: Must be 0 > > > + * > > > + * Explicitly allocate a hardware page table object. This is the same > object > > > + * type that is returned by iommufd_device_attach() and represents the > > > + * underlying iommu driver's iommu_domain kernel object. > > > + * > > > + * A normal HWPT will be created with the mappings from the given > IOAS. > > > + */ > > > > 'normal' is a confusing word in this context. > > Yea, Eric was asking about a related question in another thread, > because he couldn't get this part. I think we could replace this > "normal" with just "kernel-managed", so eventually it would look > like the following narrative after adding user_data and nesting: > > * A kernel-managed HWPT will be created with the mappings from the given > IOAS. > * The @data_type for its allocation can be set to > IOMMU_HWPT_TYPE_DEFAULT, or > * another type (being listed below) to customize the allocation. > * > * A user-managed HWPT will be created from a given parent HWPT via > @pt_id, in > * which the parent HWPT must be allocated previously via the same ioctl > from a > * given IOAS. The @data_type must not be set to > IOMMU_HWPT_TYPE_DEFAULT but a > * pre-defined type corresponding to the underlying IOMMU hardware. that is fine. But at this point it's clearer to simply remove 'normal'. 😊
