iommufd/selftest: Add coverage for the new mmap interface

Extend the loopback test to a new mmap page.

Link: https://patch.msgid.link/r/b02b1220c955c3cf9ea5dd9fe9349ab1b4f8e20b.1752126748.git.nicolinc@nvidia.com
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Pranjal Shrivastava <praan@google.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 51cd744a354f4e73adc32b7ebdf9e4628eb023bd..8fc618b2bcf9675f2af875563493bd12cef34184 100644 (file)
--- a/drivers/iommu/iommufd/iommufd_test.h
+++ b/drivers/iommu/iommufd/iommufd_test.h
@@ -232,12 +232,16 @@ struct iommu_hwpt_invalidate_selftest {
  *                                (IOMMU_VIOMMU_TYPE_SELFTEST)
  * @in_data: Input random data from user space
  * @out_data: Output data (matching @in_data) to user space
+ * @out_mmap_offset: The offset argument for mmap syscall
+ * @out_mmap_length: The length argument for mmap syscall
  *
  * Simply set @out_data=@in_data for a loopback test
  */
 struct iommu_viommu_selftest {
        __u32 in_data;
        __u32 out_data;
+       __aligned_u64 out_mmap_offset;
+       __aligned_u64 out_mmap_length;
 };
 
 /* Should not be equal to any defined value in enum iommu_viommu_invalidate_data_type */

diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index 2189e9b119eebc5c14d88d6fd033ad317e1b9923..8b2c44b3253077a030da75a15cd60d289c70fffd 100644 (file)
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -152,6 +152,9 @@ struct mock_viommu {
        struct mock_iommu_domain *s2_parent;
        struct mock_hw_queue *hw_queue[IOMMU_TEST_HW_QUEUE_MAX];
        struct mutex queue_mutex;
+
+       unsigned long mmap_offset;
+       u32 *page; /* Mmap page to test u32 type of in_data */
 };
 
 static inline struct mock_viommu *to_mock_viommu(struct iommufd_viommu *viommu)
@@ -689,6 +692,10 @@ static void mock_viommu_destroy(struct iommufd_viommu *viommu)
 
        if (refcount_dec_and_test(&mock_iommu->users))
                complete(&mock_iommu->complete);
+       if (mock_viommu->mmap_offset)
+               iommufd_viommu_destroy_mmap(&mock_viommu->core,
+                                           mock_viommu->mmap_offset);
+       free_page((unsigned long)mock_viommu->page);
        mutex_destroy(&mock_viommu->queue_mutex);
 
        /* iommufd core frees mock_viommu and viommu */
@@ -887,11 +894,28 @@ static int mock_viommu_init(struct iommufd_viommu *viommu,
                if (rc)
                        return rc;
 
+               /* Allocate two pages */
+               mock_viommu->page =
+                       (u32 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
+               if (!mock_viommu->page)
+                       return -ENOMEM;
+
+               rc = iommufd_viommu_alloc_mmap(&mock_viommu->core,
+                                              __pa(mock_viommu->page),
+                                              PAGE_SIZE * 2,
+                                              &mock_viommu->mmap_offset);
+               if (rc)
+                       goto err_free_page;
+
+               /* For loopback tests on both the page and out_data */
+               *mock_viommu->page = data.in_data;
                data.out_data = data.in_data;
+               data.out_mmap_length = PAGE_SIZE * 2;
+               data.out_mmap_offset = mock_viommu->mmap_offset;
                rc = iommu_copy_struct_to_user(
                        user_data, &data, IOMMU_VIOMMU_TYPE_SELFTEST, out_data);
                if (rc)
-                       return rc;
+                       goto err_destroy_mmap;
        }
 
        refcount_inc(&mock_iommu->users);
@@ -900,6 +924,13 @@ static int mock_viommu_init(struct iommufd_viommu *viommu,
 
        viommu->ops = &mock_viommu_ops;
        return 0;
+
+err_destroy_mmap:
+       iommufd_viommu_destroy_mmap(&mock_viommu->core,
+                                   mock_viommu->mmap_offset);
+err_free_page:
+       free_page((unsigned long)mock_viommu->page);
+       return rc;
 }
 
 static const struct iommu_ops mock_ops = {

diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index 73426de77675ae335e0b487230d45ff7b6963c54..0b21c095ca5e09ed15d179a3d2c387fab1473e7f 100644 (file)
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -2799,6 +2799,7 @@ TEST_F(iommufd_viommu, viommu_alloc_with_data)
        struct iommu_viommu_selftest data = {
                .in_data = 0xbeef,
        };
+       uint32_t *test;
 
        if (!self->device_id)
                SKIP(return, "Skipping test for variant no_viommu");
@@ -2807,6 +2808,24 @@ TEST_F(iommufd_viommu, viommu_alloc_with_data)
                              IOMMU_VIOMMU_TYPE_SELFTEST, &data, sizeof(data),
                              &self->viommu_id);
        ASSERT_EQ(data.out_data, data.in_data);
+
+       /* Negative mmap tests -- offset and length cannot be changed */
+       test_err_mmap(ENXIO, data.out_mmap_length,
+                     data.out_mmap_offset + PAGE_SIZE);
+       test_err_mmap(ENXIO, data.out_mmap_length,
+                     data.out_mmap_offset + PAGE_SIZE * 2);
+       test_err_mmap(ENXIO, data.out_mmap_length / 2, data.out_mmap_offset);
+       test_err_mmap(ENXIO, data.out_mmap_length * 2, data.out_mmap_offset);
+
+       /* Now do a correct mmap for a loopback test */
+       test = mmap(NULL, data.out_mmap_length, PROT_READ | PROT_WRITE,
+                   MAP_SHARED, self->fd, data.out_mmap_offset);
+       ASSERT_NE(MAP_FAILED, test);
+       ASSERT_EQ(data.in_data, *test);
+
+       /* The owner of the mmap region should be blocked */
+       EXPECT_ERRNO(EBUSY, _test_ioctl_destroy(self->fd, self->viommu_id));
+       munmap(test, data.out_mmap_length);
 }
 
 TEST_F(iommufd_viommu, vdevice_alloc)

diff --git a/tools/testing/selftests/iommu/iommufd_utils.h b/tools/testing/selftests/iommu/iommufd_utils.h
index 9a556f99d9924762af0ed85c7a20360813574b5a..4a1b2bade018898dade8c622d0444f2f9b357cd1 100644 (file)
--- a/tools/testing/selftests/iommu/iommufd_utils.h
+++ b/tools/testing/selftests/iommu/iommufd_utils.h
@@ -56,6 +56,10 @@ static unsigned long PAGE_SIZE;
 #define offsetofend(TYPE, MEMBER) \
        (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER))
 
+#define test_err_mmap(_errno, length, offset)                                 \
+       EXPECT_ERRNO(_errno, (long)mmap(NULL, length, PROT_READ | PROT_WRITE, \
+                                       MAP_SHARED, self->fd, offset))
+
 static inline void *memfd_mmap(size_t length, int prot, int flags, int *mfd_p)
 {
        int mfd_flags = (flags & MAP_HUGETLB) ? MFD_HUGETLB : 0;