iommufd/selftest: Add a selftest for IOMMU_HWPT_ALLOC

Test the basic flow.

Link: https://lore.kernel.org/r/19-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.comReviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/iommu/iommufd/io_pagetable.c

@@ -1180,6 +1180,9 @@ int iopt_table_enforce_dev_resv_regions(struct io_pagetable *iopt,
 	unsigned int num_sw_msi = 0;
 	int rc;
 
+	if (iommufd_should_fail())
+		return -EINVAL;
+
 	down_write(&iopt->iova_rwsem);
 	/* FIXME: drivers allocate memory but there is no failure propogated */
 	iommu_get_resv_regions(dev, &resv_regions);

tools/testing/selftests/iommu/iommufd.c

@@ -1338,6 +1338,21 @@ TEST_F(iommufd_mock_domain, replace)
 	test_ioctl_destroy(ioas_id);
 }
 
+TEST_F(iommufd_mock_domain, alloc_hwpt)
+{
+	int i;
+
+	for (i = 0; i != variant->mock_domains; i++) {
+		uint32_t stddev_id;
+		uint32_t hwpt_id;
+
+		test_cmd_hwpt_alloc(self->idev_ids[0], self->ioas_id, &hwpt_id);
+		test_cmd_mock_domain(hwpt_id, &stddev_id, NULL, NULL);
+		test_ioctl_destroy(stddev_id);
+		test_ioctl_destroy(hwpt_id);
+	}
+}
+
 /* VFIO compatibility IOCTLs */
 
 TEST_F(iommufd, simple_ioctls)

tools/testing/selftests/iommu/iommufd_fail_nth.c

@@ -579,6 +579,8 @@ TEST_FAIL_NTH(basic_fail_nth, device)
 	uint32_t ioas_id;
 	uint32_t ioas_id2;
 	uint32_t stdev_id;
+	uint32_t idev_id;
+	uint32_t hwpt_id;
 	__u64 iova;
 
 	self->fd = open("/dev/iommu", O_RDWR);
@@ -605,11 +607,18 @@ TEST_FAIL_NTH(basic_fail_nth, device)
 
 	fail_nth_enable();
 
-	if (_test_cmd_mock_domain(self->fd, ioas_id, &stdev_id, NULL, NULL))
+	if (_test_cmd_mock_domain(self->fd, ioas_id, &stdev_id, NULL,
+				  &idev_id))
+		return -1;
+
+	if (_test_cmd_hwpt_alloc(self->fd, idev_id, ioas_id, &hwpt_id))
 		return -1;
 
 	if (_test_cmd_mock_domain_replace(self->fd, stdev_id, ioas_id2, NULL))
 		return -1;
+
+	if (_test_cmd_mock_domain_replace(self->fd, stdev_id, hwpt_id, NULL))
+		return -1;
 	return 0;
 }
 

tools/testing/selftests/iommu/iommufd_utils.h

@@ -98,6 +98,27 @@ static int _test_cmd_mock_domain_replace(int fd, __u32 stdev_id, __u32 pt_id,
 	EXPECT_ERRNO(_errno, _test_cmd_mock_domain_replace(self->fd, stdev_id, \
 							   pt_id, NULL))
 
+static int _test_cmd_hwpt_alloc(int fd, __u32 device_id, __u32 pt_id,
+					 __u32 *hwpt_id)
+{
+	struct iommu_hwpt_alloc cmd = {
+		.size = sizeof(cmd),
+		.dev_id = device_id,
+		.pt_id = pt_id,
+	};
+	int ret;
+
+	ret = ioctl(fd, IOMMU_HWPT_ALLOC, &cmd);
+	if (ret)
+		return ret;
+	if (hwpt_id)
+		*hwpt_id = cmd.out_hwpt_id;
+	return 0;
+}
+
+#define test_cmd_hwpt_alloc(device_id, pt_id, hwpt_id) \
+	ASSERT_EQ(0, _test_cmd_hwpt_alloc(self->fd, device_id, pt_id, hwpt_id))
+
 static int _test_cmd_create_access(int fd, unsigned int ioas_id,
 				   __u32 *access_id, unsigned int flags)
 {