[PATCH v8 08/29] iommufd/selftest: Support user_data in mock_viommu_alloc

Nicolin Chen
2025-07-05T01:14:21Z

Add a simple user_data for an input-to-output loopback test.

Reviewed-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/iommufd/iommufd_test.h | 13 +++++++++++++
drivers/iommu/iommufd/selftest.c | 15 +++++++++++++++
2 files changed, 28 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 0d896a89ace7..38066dfeb2e7 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -784,6 +784,21 @@ static int mock_viommu_init(struct iommufd_viommu *viommu,
{
struct mock_iommu_device *mock_iommu = container_of(
viommu->iommu_dev, struct mock_iommu_device, iommu_dev);
+ struct iommu_viommu_selftest data;
+ int rc;
+
+ if (user_data) {
+ rc = iommu_copy_struct_from_user(
+ &data, user_data, IOMMU_VIOMMU_TYPE_SELFTEST, out_data);
+ if (rc)
+ return rc;
+
+ data.out_data = data.in_data;
+ rc = iommu_copy_struct_to_user(
+ user_data, &data, IOMMU_VIOMMU_TYPE_SELFTEST, out_data);
+ if (rc)
+ return rc;
+ }

refcount_inc(&mock_iommu->users);
viommu->ops = &mock_viommu_ops;
--
2.43.0