> From: Liu, Yi L <yi.l.liu@xxxxxxxxx> > Sent: Friday, November 17, 2023 9:07 PM > + > + hwpt = iommufd_hw_pagetable_get_nested(ucmd, cmd->hwpt_id); > + if (IS_ERR(hwpt)) > + return PTR_ERR(hwpt); > + > + rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain, > &data_array, > + &cmd- > >out_driver_error_code); > + cmd->req_num = data_array.entry_num; > + if (iommufd_ucmd_respond(ucmd, sizeof(*cmd))) > + return -EFAULT; > + iommufd_put_object(&hwpt->obj); the object is not put when ucmd response fails. It can be put right after calling @cache_invalidate_user() > @@ -309,6 +309,7 @@ union ucmd_buffer { > struct iommu_hwpt_alloc hwpt; > struct iommu_hwpt_get_dirty_bitmap get_dirty_bitmap; > struct iommu_hwpt_set_dirty_tracking set_dirty_tracking; > + struct iommu_hwpt_invalidate cache; In alphabetic order this should be put before "hwpt_set_dirty" > struct iommu_ioas_alloc alloc; > struct iommu_ioas_allow_iovas allow_iovas; > struct iommu_ioas_copy ioas_copy; > @@ -348,6 +349,8 @@ static const struct iommufd_ioctl_op > iommufd_ioctl_ops[] = { > struct iommu_hwpt_get_dirty_bitmap, data), > IOCTL_OP(IOMMU_HWPT_SET_DIRTY_TRACKING, > iommufd_hwpt_set_dirty_tracking, > struct iommu_hwpt_set_dirty_tracking, __reserved), > + IOCTL_OP(IOMMU_HWPT_INVALIDATE, iommufd_hwpt_invalidate, > + struct iommu_hwpt_invalidate, out_driver_error_code), ditto > +/** > + * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE) > + * @size: sizeof(struct iommu_hwpt_invalidate) > + * @hwpt_id: HWPT ID of a nested HWPT for cache invalidation remove the first 'HWPT' > + * @reqs_uptr: User pointer to an array having @req_num of cache > invalidation > + * requests. The request entries in the array are of fixed width > + * @req_len, and contain a user data structure for invalidation > + * request specific to the given hardware page table. > + * @req_type: One of enum iommu_hwpt_data_type, defining the data > type of all > + * the entries in the invalidation request array. It should suit > + * with the data_type passed per the allocation of the hwpt pointed > + * by @hwpt_id. "It should match the data_type given to the specified hwpt" > + * @req_len: Length (in bytes) of a request entry in the request array > + * @req_num: Input the number of cache invalidation requests in the array. > + * Output the number of requests successfully handled by kernel. > + * @out_driver_error_code: Report a driver speicifc error code upon failure. > + * It's optional, driver has a choice to fill it or > + * not. Being optional how does the user tell whether the code is filled or not? > + * > + * Invalidate the iommu cache for user-managed page table. Modifications > on a > + * user-managed page table should be followed by this operation to sync > cache. > + * Each ioctl can support one or more cache invalidation requests in the > array > + * that has a total size of @req_len * @req_num. > + */ > +struct iommu_hwpt_invalidate { > + __u32 size; > + __u32 hwpt_id; > + __aligned_u64 reqs_uptr; > + __u32 req_type; > + __u32 req_len; > + __u32 req_num; > + __u32 out_driver_error_code; > +}; Probably 'data_uptr', 'data_type', "entry_len' and 'entry_num" read slightly better.