[PATCH 15/17] iommufd/selftest: Add coverage for IOMMU_HWPT_ALLOC ioctl

Yi Liu
2023-02-09T04:35:50Z

From: Nicolin Chen <nicolinc@nvidia.com>

This allows to allocate hwpt for mock device to check the IOMMU_HWPT_ALLOC
in selftest.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/iommu/iommufd/device.c | 2 +-
drivers/iommu/iommufd/hw_pagetable.c | 28 ++++-
drivers/iommu/iommufd/iommufd_test.h | 16 +++
drivers/iommu/iommufd/selftest.c | 42 ++++++-
tools/testing/selftests/iommu/iommufd.c | 116 +++++++++++++++++-
tools/testing/selftests/iommu/iommufd_utils.h | 68 ++++++++++
6 files changed, 266 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index bf803975062c..ea5691468740 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -228,7 +228,7 @@ int iommufd_device_get_info(struct iommufd_ucmd *ucmd)
cmd->out_pgtbl_type_bitmap = iommufd_supported_pgtbl_types[ops->driver_type];
#ifdef CONFIG_IOMMUFD_TEST
else
- cmd->out_pgtbl_type_bitmap = 0;
+ cmd->out_pgtbl_type_bitmap = U64_MAX; // Pretend to support all types
#endif

rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index 44a75ccc8e08..1f1940969b2b 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -5,6 +5,7 @@
#include <linux/iommu.h>

#include "iommufd_private.h"
+#include "iommufd_test.h"

void iommufd_hw_pagetable_destroy(struct iommufd_object *obj)
{
@@ -111,6 +112,15 @@ static const size_t iommufd_hwpt_info_size[] = {
[IOMMU_PGTBL_DATA_VTD_S1] = sizeof(struct iommu_hwpt_intel_vtd),
};

+/* Return true if type is supported, otherwise false */
+static inline bool
+iomufd_hwpt_type_check(enum iommu_device_data_type driver_type,
+ enum iommu_pgtbl_data_type type)
+{
+ return ((1 << type) &
+ iommufd_supported_pgtbl_types[driver_type]);
+}
+
int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
{
struct iommufd_hw_pagetable *hwpt, *parent = NULL;
@@ -124,6 +134,7 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
void *data = NULL;
u32 driver_type, klen;
int rc;
+ bool support;

if (cmd->__reserved || cmd->flags)
return -EOPNOTSUPP;
@@ -148,8 +159,14 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
driver_type = ops->driver_type;

/* data_type should be a supported type by the hardware */
- if (!((1 << cmd->data_type) &
- iommufd_supported_pgtbl_types[driver_type])) {
+ if (cmd->data_type != IOMMU_PGTBL_DATA_SELFTTEST)
+ support = iomufd_hwpt_type_check(driver_type,
+ cmd->data_type);
+#ifdef CONFIG_IOMMUFD_TEST
+ else
+ support = true; /* selftest pretend to support all types */
+#endif
+ if (!support) {
rc = -EINVAL;
goto out_put_dev;
}
@@ -182,7 +199,12 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
goto out_put_pt;
}

- klen = iommufd_hwpt_info_size[cmd->data_type];
+ if (cmd->data_type != IOMMU_PGTBL_DATA_SELFTTEST)
+ klen = iommufd_hwpt_info_size[cmd->data_type];
+#ifdef CONFIG_IOMMUFD_TEST
+ else
+ klen = sizeof(struct iommu_hwpt_selftest);
+#endif
if (klen) {
if (!cmd->data_len) {
rc = -EINVAL;
diff --git a/drivers/iommu/iommufd/iommufd_test.h b/drivers/iommu/iommufd/iommufd_test.h
index a73ab51afe79..842b81397a2a 100644
--- a/drivers/iommu/iommufd/iommufd_test.h
+++ b/drivers/iommu/iommufd/iommufd_test.h
@@ -114,4 +114,20 @@ struct iommu_device_info_selftest {
__u32 test_reg;
};

+/* Should not be equal to any defined value in enum iommu_pgtbl_data_type */
+#define IOMMU_PGTBL_DATA_SELFTTEST 0xbadbeef
+
+/**
+ * struct iommu_hwpt_selftest
+ *
+ * @flags: page table entry attributes
+ * @test_config: default iotlb setup (value IOMMU_TEST_IOTLB_DEFAULT)
+ */
+struct iommu_hwpt_selftest {
+#define IOMMU_TEST_FLAG_NESTED (1 << 0)
+ __u64 flags;
+#define IOMMU_TEST_IOTLB_DEFAULT 0xbadbeef
+ __u64 test_config;
+};
+
#endif
diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index 3623a42648d5..354a0054afad 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -84,7 +84,9 @@ void iommufd_test_syz_conv_iova_id(struct iommufd_ucmd *ucmd,

struct mock_iommu_domain {
struct iommu_domain domain;
+ struct mock_iommu_domain *parent;
struct xarray pfns;
+ u32 iotlb;
};

enum selftest_obj_type {
@@ -119,6 +121,8 @@ static void *mock_domain_hw_info(struct device *dev, u32 *length)
return info;
}

+static const struct iommu_ops mock_ops;
+
static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type)
{
struct mock_iommu_domain *mock;
@@ -132,10 +136,38 @@ static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type)
mock->domain.geometry.aperture_start = MOCK_APERTURE_START;
mock->domain.geometry.aperture_end = MOCK_APERTURE_LAST;
mock->domain.pgsize_bitmap = MOCK_IO_PAGE_SIZE;
+ mock->domain.ops = mock_ops.default_domain_ops;
+ mock->domain.type = IOMMU_DOMAIN_UNMANAGED;
xa_init(&mock->pfns);
return &mock->domain;
}

+static struct iommu_domain_ops domain_nested_ops;
+
+static struct iommu_domain *mock_domain_alloc_user(struct device *dev,
+ struct iommu_domain *parent,
+ const void *user_data)
+{
+ const struct iommu_hwpt_selftest *alloc = user_data;
+ struct mock_iommu_domain *mock_parent;
+ struct mock_iommu_domain *mock;
+
+ if (!parent || !alloc || !(alloc->flags & IOMMU_TEST_FLAG_NESTED))
+ return mock_domain_alloc(IOMMU_DOMAIN_UNMANAGED);
+
+ mock_parent = container_of(parent, struct mock_iommu_domain, domain);
+
+ mock = kzalloc(sizeof(*mock), GFP_KERNEL);
+ if (!mock)
+ return NULL;
+ mock->parent = mock_parent;
+ mock->iotlb = alloc->test_config;
+ mock->domain.pgsize_bitmap = MOCK_IO_PAGE_SIZE;
+ mock->domain.ops = &domain_nested_ops;
+ mock->domain.type = IOMMU_DOMAIN_NESTED;
+ return &mock->domain;
+}
+
static void mock_domain_free(struct iommu_domain *domain)
{
struct mock_iommu_domain *mock =
@@ -257,6 +289,7 @@ static const struct iommu_ops mock_ops = {
.driver_type = IOMMU_DEVICE_DATA_SELFTEST,
.hw_info = mock_domain_hw_info,
.domain_alloc = mock_domain_alloc,
+ .domain_alloc_user = mock_domain_alloc_user,
.default_domain_ops =
&(struct iommu_domain_ops){
.free = mock_domain_free,
@@ -266,6 +299,10 @@ static const struct iommu_ops mock_ops = {
},
};

+static struct iommu_domain_ops domain_nested_ops = {
+ .free = mock_domain_free,
+};
+
static inline struct iommufd_hw_pagetable *
get_md_pagetable(struct iommufd_ucmd *ucmd, u32 mockpt_id,
struct mock_iommu_domain **mock)
@@ -278,7 +315,10 @@ get_md_pagetable(struct iommufd_ucmd *ucmd, u32 mockpt_id,
if (IS_ERR(obj))
return ERR_CAST(obj);
hwpt = container_of(obj, struct iommufd_hw_pagetable, obj);
- if (hwpt->domain->ops != mock_ops.default_domain_ops) {
+ if ((hwpt->domain->type == IOMMU_DOMAIN_UNMANAGED &&
+ hwpt->domain->ops != mock_ops.default_domain_ops) ||
+ (hwpt->domain->type == IOMMU_DOMAIN_NESTED &&
+ hwpt->domain->ops != &domain_nested_ops)) {
iommufd_put_object(&hwpt->obj);
return ERR_PTR(-EINVAL);
}
diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index 8e1369451464..ddd7c898fc50 100644
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -125,6 +125,7 @@ TEST_F(iommufd, cmd_length)
TEST_LENGTH(iommu_option, IOMMU_OPTION);
TEST_LENGTH(iommu_vfio_ioas, IOMMU_VFIO_IOAS);
TEST_LENGTH(iommu_device_info, IOMMU_DEVICE_GET_INFO);
+ TEST_LENGTH(iommu_hwpt_alloc, IOMMU_HWPT_ALLOC);
#undef TEST_LENGTH
}

@@ -196,6 +197,7 @@ FIXTURE_VARIANT(iommufd_ioas)
{
unsigned int mock_domains;
unsigned int memory_limit;
+ bool new_hwpt;
};

FIXTURE_SETUP(iommufd_ioas)
@@ -235,6 +237,12 @@ FIXTURE_VARIANT_ADD(iommufd_ioas, mock_domain)
.mock_domains = 1,
};

+FIXTURE_VARIANT_ADD(iommufd_ioas, mock_domain_hwpt)
+{
+ .mock_domains = 1,
+ .new_hwpt = true,
+};
+
FIXTURE_VARIANT_ADD(iommufd_ioas, two_mock_domain)
{
.mock_domains = 2,
@@ -250,6 +258,96 @@ TEST_F(iommufd_ioas, ioas_auto_destroy)
{
}

+TEST_F(iommufd_ioas, ioas_new_hwpt)
+{
+ uint32_t new_hwpt_id = 0;
+ bool nested = true;
+
+ if (self->dev_id) {
+ test_cmd_mock_domain_alloc_and_replace(self->ioas_id,
+ self->dev_id,
+ &new_hwpt_id, !nested);
+ /* hw_pagetable cannot be freed if a device is attached to it */
+ EXPECT_ERRNO(EBUSY, _test_ioctl_destroy(self->fd, new_hwpt_id));
+
+ /* Detach from the new hw_pagetable and try again */
+ test_cmd_mock_domain_replace(self->ioas_id, self->dev_id,
+ self->domain_id);
+ test_ioctl_destroy(new_hwpt_id);
+ } else {
+ test_err_ioctl_hwpt_alloc(ENOENT, self->ioas_id, self->dev_id,
+ &new_hwpt_id, !nested);
+ test_err_mock_domain_replace(ENOENT, self->ioas_id,
+ self->dev_id, new_hwpt_id);
+ }
+}
+
+TEST_F(iommufd_ioas, ioas_nested_hwpt)
+{
+ uint32_t nested_hwpt_id[2] = {};
+ uint32_t parent_hwpt_id = 0;
+ uint32_t test_hwpt_id = 0;
+ bool nested = true;
+
+ if (self->dev_id) {
+ /* Negative tests */
+ test_err_ioctl_hwpt_alloc(EINVAL, self->dev_id,
+ self->ioas_id, &test_hwpt_id, !nested);
+ test_err_ioctl_hwpt_alloc(EINVAL, self->dev_id,
+ self->dev_id, &test_hwpt_id, !nested);
+
+ /* Allocate two nested hwpts sharing one common parent hwpt */
+ test_ioctl_hwpt_alloc(self->ioas_id, self->dev_id,
+ &parent_hwpt_id, !nested);
+
+ test_ioctl_hwpt_alloc(parent_hwpt_id, self->dev_id,
+ &nested_hwpt_id[0], nested);
+ test_ioctl_hwpt_alloc(parent_hwpt_id, self->dev_id,
+ &nested_hwpt_id[1], nested);
+
+ /* Negative test: a nested hwpt on top of a nested hwpt */
+ test_err_ioctl_hwpt_alloc(EINVAL, nested_hwpt_id[0],
+ self->dev_id, &test_hwpt_id, nested);
+ /* Negative test: parent hwpt now cannot be freed */
+ EXPECT_ERRNO(EBUSY,
+ _test_ioctl_destroy(self->fd, parent_hwpt_id));
+
+ /* Attach device to nested_hwpt_id[0] that then will be busy */
+ test_cmd_mock_domain_replace(self->ioas_id, self->dev_id,
+ nested_hwpt_id[0]);
+ EXPECT_ERRNO(EBUSY,
+ _test_ioctl_destroy(self->fd, nested_hwpt_id[0]));
+
+ /* Switch from nested_hwpt_id[0] to nested_hwpt_id[1] */
+ test_cmd_mock_domain_replace(self->ioas_id, self->dev_id,
+ nested_hwpt_id[1]);
+ EXPECT_ERRNO(EBUSY,
+ _test_ioctl_destroy(self->fd, nested_hwpt_id[1]));
+ test_ioctl_destroy(nested_hwpt_id[0]);
+
+ /* Detach from nested_hwpt_id[1] and destroy it */
+ test_cmd_mock_domain_replace(self->ioas_id, self->dev_id,
+ parent_hwpt_id);
+ test_ioctl_destroy(nested_hwpt_id[1]);
+
+ /* Detach from the parent hw_pagetable and destroy it */
+ test_cmd_mock_domain_replace(self->ioas_id, self->dev_id,
+ self->domain_id);
+ test_ioctl_destroy(parent_hwpt_id);
+ } else {
+ test_err_ioctl_hwpt_alloc(ENOENT, self->ioas_id, self->dev_id,
+ &parent_hwpt_id, false);
+ test_err_ioctl_hwpt_alloc(ENOENT, parent_hwpt_id, self->dev_id,
+ &nested_hwpt_id[0], true);
+ test_err_ioctl_hwpt_alloc(ENOENT, parent_hwpt_id, self->dev_id,
+ &nested_hwpt_id[1], true);
+ test_err_mock_domain_replace(ENOENT, self->ioas_id,
+ self->dev_id, nested_hwpt_id[0]);
+ test_err_mock_domain_replace(ENOENT, self->ioas_id,
+ self->dev_id, nested_hwpt_id[1]);
+ }
+}
+
TEST_F(iommufd_ioas, ioas_destroy)
{
if (self->domain_id) {
@@ -621,6 +719,7 @@ TEST_F(iommufd_ioas, access_pin)
MOCK_FLAGS_ACCESS_CREATE_NEEDS_PIN_PAGES);

for (npages = 1; npages < BUFFER_SIZE / PAGE_SIZE; npages++) {
+ uint32_t new_hwpt_id = 0;
uint32_t mock_device_id;
uint32_t mock_hwpt_id;

@@ -655,11 +754,26 @@ TEST_F(iommufd_ioas, access_pin)
&access_cmd));
test_cmd_mock_domain(self->ioas_id, &mock_device_id,
&mock_hwpt_id);
- check_map_cmd.id = mock_hwpt_id;
+ if (variant->new_hwpt) {
+ test_cmd_mock_domain_alloc_and_replace(self->ioas_id,
+ mock_device_id,
+ &new_hwpt_id,
+ false);
+ check_map_cmd.id = new_hwpt_id;
+ } else {
+ check_map_cmd.id = mock_hwpt_id;
+ }
ASSERT_EQ(0, ioctl(self->fd,
_IOMMU_TEST_CMD(IOMMU_TEST_OP_MD_CHECK_MAP),
&check_map_cmd));

+ if (variant->new_hwpt) {
+ /* Detach from the new hwpt for its destroy() */
+ test_cmd_mock_domain_replace(self->ioas_id,
+ mock_device_id,
+ mock_hwpt_id);
+ test_ioctl_destroy(new_hwpt_id);
+ }
test_ioctl_destroy(mock_device_id);
test_ioctl_destroy(mock_hwpt_id);
test_cmd_destroy_access_pages(
diff --git a/tools/testing/selftests/iommu/iommufd_utils.h b/tools/testing/selftests/iommu/iommufd_utils.h
index 1807d29c05f8..cb8a5e3beca6 100644
--- a/tools/testing/selftests/iommu/iommufd_utils.h
+++ b/tools/testing/selftests/iommu/iommufd_utils.h
@@ -66,6 +66,36 @@ static int _test_cmd_mock_domain(int fd, unsigned int ioas_id, __u32 *device_id,
EXPECT_ERRNO(_errno, _test_cmd_mock_domain(self->fd, ioas_id, \
device_id, hwpt_id))

+static int _test_cmd_mock_domain_replace(int fd, unsigned int ioas_id,
+ __u32 device_id, __u32 hwpt_id)
+{
+ struct iommu_test_cmd cmd = {
+ .size = sizeof(cmd),
+ .op = IOMMU_TEST_OP_MOCK_DOMAIN_REPLACE,
+ .id = ioas_id,
+ .mock_domain_replace = {
+ .device_id = device_id,
+ .hwpt_id = hwpt_id,
+ },
+ };
+
+ return ioctl(fd, IOMMU_TEST_CMD, &cmd);
+}
+
+#define test_cmd_mock_domain_replace(ioas_id, device_id, hwpt_id) \
+ ASSERT_EQ(0, _test_cmd_mock_domain_replace(self->fd, ioas_id, device_id, \
+ hwpt_id))
+#define test_err_mock_domain_replace(_errno, ioas_id, device_id, hwpt_id) \
+ EXPECT_ERRNO(_errno, _test_cmd_mock_domain_replace(self->fd, ioas_id, \
+ device_id, hwpt_id))
+
+#define test_cmd_mock_domain_alloc_and_replace(ioas_id, device_id, \
+ hwpt_id, nested) \
+ ({ \
+ test_ioctl_hwpt_alloc(ioas_id, device_id, hwpt_id, nested); \
+ test_cmd_mock_domain_replace(ioas_id, device_id, *(hwpt_id)); \
+ })
+
static int _test_cmd_access_set_ioas(int fd, __u32 access_id,
unsigned int ioas_id)
{
@@ -159,6 +189,44 @@ static int _test_ioctl_ioas_alloc(int fd, __u32 *id)
ASSERT_NE(0, *(id)); \
})

+static int _test_ioctl_hwpt_alloc(int fd, __u32 pt_id, __u32 dev_id,
+ __u32 *out_hwpt_id, bool nested)
+{
+ struct iommu_hwpt_selftest data = {
+ .flags = nested ? IOMMU_TEST_FLAG_NESTED : 0,
+ .test_config = nested ? IOMMU_TEST_IOTLB_DEFAULT : 0,
+ };
+ struct iommu_hwpt_alloc cmd = {
+ .size = sizeof(cmd),
+ .dev_id = dev_id,
+ .pt_id = pt_id,
+ .data_type = IOMMU_PGTBL_DATA_SELFTTEST,
+ .data_len = sizeof(data),
+ .data_uptr = (uint64_t)&data,
+ };
+ int ret;
+
+ ret = ioctl(fd, IOMMU_HWPT_ALLOC, &cmd);
+ if (ret)
+ return ret;
+ *out_hwpt_id = cmd.out_hwpt_id;
+ return 0;
+}
+
+#define test_ioctl_hwpt_alloc(pt_id, dev_id, out_hwpt_id, nested) \
+ ({ \
+ ASSERT_EQ(0, _test_ioctl_hwpt_alloc(self->fd, pt_id, dev_id, \
+ out_hwpt_id, nested)); \
+ ASSERT_NE(0, *(out_hwpt_id)); \
+ })
+#define test_err_ioctl_hwpt_alloc(_errno, pt_id, dev_id, out_hwpt_id, nested) \
+ ({ \
+ EXPECT_ERRNO(_errno, \
+ _test_ioctl_hwpt_alloc(self->fd, pt_id, dev_id, \
+ out_hwpt_id, nested)); \
+ ASSERT_EQ(0, *(out_hwpt_id)); \
+ })
+
static int _test_ioctl_ioas_map(int fd, unsigned int ioas_id, void *buffer,
size_t length, __u64 *iova, unsigned int flags)
{
--
2.34.1