iommufd/selftest: Add coverage for reporting max_pasid_log2 via IOMMU_HW_INFO

commit 6d9500b
Author: Yi Liu <yi.l.liu@intel.com>
Date: Fri Mar 21 11:01:43 2025 -0700

    iommufd/selftest: Add coverage for reporting max_pasid_log2 via IOMMU_HW_INFO

    IOMMU_HW_INFO is extended to report max_pasid_log2, hence add coverage
    for it.

    Link: https://patch.msgid.link/r/20250321180143.8468-6-yi.l.liu@intel.com
    Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
    Tested-by: Nicolin Chen <nicolinc@nvidia.com>
    Signed-off-by: Yi Liu <yi.l.liu@intel.com>
    Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

(cherry picked from commit 6d9500b)
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Upstream-Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
JIRA: https://issues.redhat.com/browse/RHEL-73603

Author: snits

tools/testing/selftests/iommu/iommufd.c

@@ -342,12 +342,14 @@ FIXTURE(iommufd_ioas)
 	uint32_t hwpt_id;
 	uint32_t device_id;
 	uint64_t base_iova;
+	uint32_t device_pasid_id;
 };
 
 FIXTURE_VARIANT(iommufd_ioas)
 {
 	unsigned int mock_domains;
 	unsigned int memory_limit;
+	bool pasid_capable;
 };
 
 FIXTURE_SETUP(iommufd_ioas)
@@ -372,6 +374,12 @@ FIXTURE_SETUP(iommufd_ioas)
 					     IOMMU_TEST_DEV_CACHE_DEFAULT);
 		self->base_iova = MOCK_APERTURE_START;
 	}
+
+	if (variant->pasid_capable)
+		test_cmd_mock_domain_flags(self->ioas_id,
+					   MOCK_FLAGS_DEVICE_PASID,
+					   NULL, NULL,
+					   &self->device_pasid_id);
 }
 
 FIXTURE_TEARDOWN(iommufd_ioas)
@@ -387,6 +395,7 @@ FIXTURE_VARIANT_ADD(iommufd_ioas, no_domain)
 FIXTURE_VARIANT_ADD(iommufd_ioas, mock_domain)
 {
 	.mock_domains = 1,
+	.pasid_capable = true,
 };
 
 FIXTURE_VARIANT_ADD(iommufd_ioas, two_mock_domain)
@@ -752,6 +761,8 @@ TEST_F(iommufd_ioas, get_hw_info)
 	} buffer_smaller;
 
 	if (self->device_id) {
+		uint8_t max_pasid = 0;
+
 		/* Provide a zero-size user_buffer */
 		test_cmd_get_hw_info(self->device_id, NULL, 0);
 		/* Provide a user_buffer with exact size */
@@ -766,6 +777,13 @@ TEST_F(iommufd_ioas, get_hw_info)
 		 * the fields within the size range still gets updated.
 		 */
 		test_cmd_get_hw_info(self->device_id, &buffer_smaller, sizeof(buffer_smaller));
+		test_cmd_get_hw_info_pasid(self->device_id, &max_pasid);
+		ASSERT_EQ(0, max_pasid);
+		if (variant->pasid_capable) {
+			test_cmd_get_hw_info_pasid(self->device_pasid_id,
+						   &max_pasid);
+			ASSERT_EQ(MOCK_PASID_WIDTH, max_pasid);
+		}
 	} else {
 		test_err_get_hw_info(ENOENT, self->device_id,
 				     &buffer_exact, sizeof(buffer_exact));

tools/testing/selftests/iommu/iommufd_fail_nth.c

@@ -666,7 +666,8 @@ TEST_FAIL_NTH(basic_fail_nth, device)
 					&self->stdev_id, NULL, &idev_id))
 		return -1;
 
-	if (_test_cmd_get_hw_info(self->fd, idev_id, &info, sizeof(info), NULL))
+	if (_test_cmd_get_hw_info(self->fd, idev_id, &info,
+				  sizeof(info), NULL, NULL))
 		return -1;
 
 	if (_test_cmd_hwpt_alloc(self->fd, idev_id, ioas_id, 0,

tools/testing/selftests/iommu/iommufd_utils.h

@@ -758,7 +758,8 @@ static void teardown_iommufd(int fd, struct __test_metadata *_metadata)
 
 /* @data can be NULL */
 static int _test_cmd_get_hw_info(int fd, __u32 device_id, void *data,
-				 size_t data_len, uint32_t *capabilities)
+				 size_t data_len, uint32_t *capabilities,
+				 uint8_t *max_pasid)
 {
 	struct iommu_test_hw_info *info = (struct iommu_test_hw_info *)data;
 	struct iommu_hw_info cmd = {
@@ -803,6 +804,9 @@ static int _test_cmd_get_hw_info(int fd, __u32 device_id, void *data,
 			assert(!info->flags);
 	}
 
+	if (max_pasid)
+		*max_pasid = cmd.out_max_pasid_log2;
+
 	if (capabilities)
 		*capabilities = cmd.out_capabilities;
 
@@ -811,14 +815,19 @@ static int _test_cmd_get_hw_info(int fd, __u32 device_id, void *data,
 
 #define test_cmd_get_hw_info(device_id, data, data_len)               \
 	ASSERT_EQ(0, _test_cmd_get_hw_info(self->fd, device_id, data, \
-					   data_len, NULL))
+					   data_len, NULL, NULL))
 
 #define test_err_get_hw_info(_errno, device_id, data, data_len)               \
 	EXPECT_ERRNO(_errno, _test_cmd_get_hw_info(self->fd, device_id, data, \
-						   data_len, NULL))
+						   data_len, NULL, NULL))
 
 #define test_cmd_get_hw_capabilities(device_id, caps, mask) \
-	ASSERT_EQ(0, _test_cmd_get_hw_info(self->fd, device_id, NULL, 0, &caps))
+	ASSERT_EQ(0, _test_cmd_get_hw_info(self->fd, device_id, NULL, \
+					   0, &caps, NULL))
+
+#define test_cmd_get_hw_info_pasid(device_id, max_pasid)              \
+	ASSERT_EQ(0, _test_cmd_get_hw_info(self->fd, device_id, NULL, \
+					   0, NULL, max_pasid))
 
 static int _test_ioctl_fault_alloc(int fd, __u32 *fault_id, __u32 *fault_fd)
 {