[v6,5/6] iommufd/selftest: Add IOMMU_TEST_OP_MD_CHECK_IOTLB test op

diff --git a/drivers/iommu/iommufd/iommufd_test.h b/drivers/iommu/iommufd/iommufd_test.h
index 0000f58dcda3..35d6207a96dd 100644
--- a/drivers/iommu/iommufd/iommufd_test.h
+++ b/drivers/iommu/iommufd/iommufd_test.h
@@ -21,6 +21,7 @@  enum {
 	IOMMU_TEST_OP_ACCESS_REPLACE_IOAS,
 	IOMMU_TEST_OP_MOCK_DOMAIN_FLAGS,
 	IOMMU_TEST_OP_DIRTY,
+	IOMMU_TEST_OP_MD_CHECK_IOTLB,
 };
 
 enum {
@@ -121,6 +122,10 @@  struct iommu_test_cmd {
 			__aligned_u64 uptr;
 			__aligned_u64 out_nr_dirty;
 		} dirty;
+		struct {
+			__u32 id;
+			__u32 iotlb;
+		} check_iotlb;
 	};
 	__u32 last;
 };
diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index 2a9b970ca84e..f2d4599f701b 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -836,6 +836,28 @@  static int iommufd_test_md_check_refs(struct iommufd_ucmd *ucmd,
 	return 0;
 }
 
+static int iommufd_test_md_check_iotlb(struct iommufd_ucmd *ucmd,
+				       u32 mockpt_id, unsigned int iotlb_id,
+				       u32 iotlb)
+{
+	struct mock_iommu_domain_nested *mock_nested;
+	struct iommufd_hw_pagetable *hwpt;
+	int rc = 0;
+
+	hwpt = get_md_pagetable_nested(ucmd, mockpt_id, &mock_nested);
+	if (IS_ERR(hwpt))
+		return PTR_ERR(hwpt);
+
+	mock_nested = container_of(hwpt->domain,
+				   struct mock_iommu_domain_nested, domain);
+
+	if (iotlb_id > MOCK_NESTED_DOMAIN_IOTLB_ID_MAX ||
+	    mock_nested->iotlb[iotlb_id] != iotlb)
+		rc = -EINVAL;
+	iommufd_put_object(&hwpt->obj);
+	return rc;
+}
+
 struct selftest_access {
 	struct iommufd_access *access;
 	struct file *file;
@@ -1317,6 +1339,10 @@  int iommufd_test(struct iommufd_ucmd *ucmd)
 		return iommufd_test_md_check_refs(
 			ucmd, u64_to_user_ptr(cmd->check_refs.uptr),
 			cmd->check_refs.length, cmd->check_refs.refs);
+	case IOMMU_TEST_OP_MD_CHECK_IOTLB:
+		return iommufd_test_md_check_iotlb(ucmd, cmd->id,
+						   cmd->check_iotlb.id,
+						   cmd->check_iotlb.iotlb);
 	case IOMMU_TEST_OP_CREATE_ACCESS:
 		return iommufd_test_create_access(ucmd, cmd->id,
 						  cmd->create_access.flags);
diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index 6ed328c863c4..c8763b880a16 100644
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -330,6 +330,10 @@  TEST_F(iommufd_ioas, alloc_hwpt_nested)
 					   &nested_hwpt_id[1],
 					   IOMMU_HWPT_DATA_SELFTEST, &data,
 					   sizeof(data));
+		test_cmd_hwpt_check_iotlb_all(nested_hwpt_id[0],
+					      IOMMU_TEST_IOTLB_DEFAULT);
+		test_cmd_hwpt_check_iotlb_all(nested_hwpt_id[1],
+					      IOMMU_TEST_IOTLB_DEFAULT);
 
 		/* Negative test: a nested hwpt on top of a nested hwpt */
 		test_err_hwpt_alloc_nested(EINVAL, self->device_id,
diff --git a/tools/testing/selftests/iommu/iommufd_utils.h b/tools/testing/selftests/iommu/iommufd_utils.h
index 050e9751321c..69561ba9e7aa 100644
--- a/tools/testing/selftests/iommu/iommufd_utils.h
+++ b/tools/testing/selftests/iommu/iommufd_utils.h
@@ -195,6 +195,30 @@  static int _test_cmd_hwpt_alloc(int fd, __u32 device_id, __u32 pt_id,
 		     _test_cmd_hwpt_alloc(self->fd, device_id, pt_id, flags, \
 					  hwpt_id, data_type, data, data_len))
 
+#define test_cmd_hwpt_check_iotlb(hwpt_id, iotlb_id, expected)                 \
+	({                                                                     \
+		struct iommu_test_cmd test_cmd = {                             \
+			.size = sizeof(test_cmd),                              \
+			.op = IOMMU_TEST_OP_MD_CHECK_IOTLB,                    \
+			.id = hwpt_id,                                         \
+			.check_iotlb = {                                       \
+				.id = iotlb_id,                                \
+				.iotlb = expected,                             \
+			},                                                     \
+		};                                                             \
+		ASSERT_EQ(0,                                                   \
+			  ioctl(self->fd,                                      \
+				_IOMMU_TEST_CMD(IOMMU_TEST_OP_MD_CHECK_IOTLB), \
+				&test_cmd));                                   \
+	})
+
+#define test_cmd_hwpt_check_iotlb_all(hwpt_id, expected)                       \
+	({                                                                     \
+		int i;                                                         \
+		for (i = 0; i < MOCK_NESTED_DOMAIN_IOTLB_NUM; i++)             \
+			test_cmd_hwpt_check_iotlb(hwpt_id, i, expected);       \
+	})
+
 static int _test_cmd_access_replace_ioas(int fd, __u32 access_id,
 					 unsigned int ioas_id)
 {