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

[Pranjal Shrivastava]

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 at 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 at google.com>

> -- 
> 2.43.0
>