From: Nicolin Chen <nicolinc@nvidia.com>
Date: Thu, 10 Jul 2025 05:59:00 +0000 (-0700)
Subject: iommufd/selftest: Support user_data in mock_viommu_alloc
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=afeaf592c1d435b8773471880c6c349506569cac;p=thirdparty%2Fkernel%2Flinux.git

iommufd/selftest: Support user_data in mock_viommu_alloc

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

Link: https://patch.msgid.link/r/cae4632bb3d98a1efb3b77488fbf81814f2041c6.1752126748.git.nicolinc@nvidia.com
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---

diff --git a/drivers/iommu/iommufd/iommufd_test.h b/drivers/iommu/iommufd/iommufd_test.h
index 1cd7e83941298..fbf9ecb35a137 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 0d896a89ace75..38066dfeb2e76 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;