Re: [PATCH v7 3/3] iommu/vt-d: Add iotlb flush for nested domain

Jason Gunthorpe
2023-12-06T18:57:01Z

On Fri, Nov 17, 2023 at 05:18:16AM -0800, Yi Liu wrote:
> +static int intel_nested_cache_invalidate_user(struct iommu_domain *domain,
> + struct iommu_user_data_array *array,
> + u32 *cerror_idx)
> +{
> + struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> + struct iommu_hwpt_vtd_s1_invalidate inv_info;
> + u32 index;
> + int ret;
> +
> + /* REVISIT:
> + * VT-d has defined ITE, ICE, IQE for invalidation failure per hardware,
> + * but no error code yet, so just set the error code to be 0.
> + */
> + *cerror_idx = 0;
> +
> + for (index = 0; index < array->entry_num; index++) {
> + ret = iommu_copy_struct_from_user_array(&inv_info, array,
> + IOMMU_HWPT_DATA_VTD_S1,
> + index, __reserved);
> + if (ret) {
> + pr_err_ratelimited("Failed to fetch invalidation request\n");
> + break;

No error prints on ioctls!

> + if (inv_info.addr == 0 && inv_info.npages == -1)
> + intel_flush_iotlb_all(domain);

-1 is clearer written as U64_MAX - same remark for the comment
documenting it.

Jason