Re: [PATCH v2 06/22] iommufd/selftest: Support user_data in mock_viommu_alloc

Pranjal Shrivastava
2025-04-28T20:01:15Z

On Fri, Apr 25, 2025 at 10:58:01PM -0700, Nicolin Chen wrote:
> Add a simple user_data for an input-to-output loopback test.
>
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> ---
> drivers/iommu/iommufd/iommufd_test.h | 13 +++++++++++++
> drivers/iommu/iommufd/selftest.c | 19 +++++++++++++++++++
> 2 files changed, 32 insertions(+)
>
> diff --git a/drivers/iommu/iommufd/iommufd_test.h b/drivers/iommu/iommufd/iommufd_test.h
> index 1cd7e8394129..fbf9ecb35a13 100644
> --- a/drivers/iommu/iommufd/iommufd_test.h
> +++ b/drivers/iommu/iommufd/iommufd_test.h
> @@ -227,6 +227,19 @@ struct iommu_hwpt_invalidate_selftest {
>
> #define IOMMU_VIOMMU_TYPE_SELFTEST 0xdeadbeef
>
> +/**
> + * struct iommu_viommu_selftest - vIOMMU data for Mock driver
> + * (IOMMU_VIOMMU_TYPE_SELFTEST)
> + * @in_data: Input random data from user space
> + * @out_data: Output data (matching @in_data) to user space
> + *
> + * Simply set @out_data=@in_data for a loopback test
> + */
> +struct iommu_viommu_selftest {
> + __u32 in_data;
> + __u32 out_data;
> +};
> +
> /* Should not be equal to any defined value in enum iommu_viommu_invalidate_data_type */
> #define IOMMU_VIOMMU_INVALIDATE_DATA_SELFTEST 0xdeadbeef
> #define IOMMU_VIOMMU_INVALIDATE_DATA_SELFTEST_INVALID 0xdadbeef
> diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
> index 8b8ba4fb91cd..b04bd2fbc53d 100644
> --- a/drivers/iommu/iommufd/selftest.c
> +++ b/drivers/iommu/iommufd/selftest.c
> @@ -740,16 +740,35 @@ mock_viommu_alloc(struct device *dev, struct iommu_domain *domain,
> {
> struct mock_iommu_device *mock_iommu =
> iommu_get_iommu_dev(dev, struct mock_iommu_device, iommu_dev);
> + struct iommu_viommu_selftest data;
> struct mock_viommu *mock_viommu;
> + int rc;
>
> if (viommu_type != IOMMU_VIOMMU_TYPE_SELFTEST)
> return ERR_PTR(-EOPNOTSUPP);
>
> + if (user_data) {
> + rc = iommu_copy_struct_from_user(
> + &data, user_data, IOMMU_VIOMMU_TYPE_SELFTEST, out_data);
> + if (rc)
> + return ERR_PTR(rc);
> + }
> +
> mock_viommu = iommufd_viommu_alloc(ictx, struct mock_viommu, core,
> &mock_viommu_ops);
> if (IS_ERR(mock_viommu))
> return ERR_CAST(mock_viommu);
>
> + if (user_data) {
> + data.out_data = data.in_data;
> + rc = iommu_copy_struct_to_user(
> + user_data, &data, IOMMU_VIOMMU_TYPE_SELFTEST, out_data);
> + if (rc) {
> + iommufd_struct_destroy(ictx, mock_viommu, core);
> + return ERR_PTR(rc);
> + }
> + }
> +
> refcount_inc(&mock_iommu->users);
> return &mock_viommu->core;
> }

Builds fine for me.

Reviewed-by: Pranjal Shrivastava <praan@google.com>

> --
> 2.43.0
>