[PATCH 4/4] vfio: selftests: Add tests to validate SR-IOV UAPI

[Raghavendra Rao Ananta <rananta@google.com>]

Add a test to validate the SR-IOV UAPI, including the following cases,
iterating over all the IOMMU modes currently supported:
 - Setting correct/incorrect/NULL tokens during device init.
 - Close the PF device immediately after setting the token.
 - Change/override the PF's token after device init.

Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
---
 tools/testing/selftests/vfio/Makefile         |   1 +
 .../selftests/vfio/vfio_pci_sriov_uapi_test.c | 220 ++++++++++++++++++
 2 files changed, 221 insertions(+)
 create mode 100644 tools/testing/selftests/vfio/vfio_pci_sriov_uapi_test.c

diff --git a/tools/testing/selftests/vfio/Makefile b/tools/testing/selftests/vfio/Makefile
index 324ba0175a333..e9fad0acf4d13 100644
--- a/tools/testing/selftests/vfio/Makefile
+++ b/tools/testing/selftests/vfio/Makefile
@@ -3,6 +3,7 @@ TEST_GEN_PROGS += vfio_dma_mapping_test
 TEST_GEN_PROGS += vfio_iommufd_setup_test
 TEST_GEN_PROGS += vfio_pci_device_test
 TEST_GEN_PROGS += vfio_pci_driver_test
+TEST_GEN_PROGS += vfio_pci_sriov_uapi_test
 TEST_PROGS_EXTENDED := run.sh
 include ../lib.mk
 include lib/libvfio.mk
diff --git a/tools/testing/selftests/vfio/vfio_pci_sriov_uapi_test.c b/tools/testing/selftests/vfio/vfio_pci_sriov_uapi_test.c
new file mode 100644
index 0000000000000..4d63359053230
--- /dev/null
+++ b/tools/testing/selftests/vfio/vfio_pci_sriov_uapi_test.c
@@ -0,0 +1,220 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <linux/limits.h>
+
+#include <vfio_util.h>
+
+#include "../kselftest_harness.h"
+
+#define PCI_SYSFS_PATH "/sys/bus/pci/devices"
+
+#define UUID_1 "52ac9bff-3a88-4fbd-901a-0d767c3b6c97"
+#define UUID_2 "88594674-90a0-47a9-aea8-9d9b352ac08a"
+
+static const char *pf_dev_bdf;
+static char vf_dev_bdf[16];
+
+struct vfio_pci_device *pf_device;
+struct vfio_pci_device *vf_device;
+
+static void test_vfio_pci_container_setup(struct vfio_pci_device *device,
+					   const char *bdf,
+					   const char *vf_token)
+{
+	vfio_container_open(device);
+	vfio_pci_group_setup(device, bdf);
+	vfio_container_set_iommu(device);
+	__vfio_container_get_device_fd(device, bdf, vf_token);
+}
+
+static int test_vfio_pci_iommufd_setup(struct vfio_pci_device *device,
+					const char *bdf, const char *vf_token)
+{
+	vfio_pci_iommufd_cdev_open(device, bdf);
+	vfio_pci_iommufd_iommudev_open(device);
+	return __vfio_device_bind_iommufd(device->fd, device->iommufd, vf_token);
+}
+
+static struct vfio_pci_device *test_vfio_pci_device_init(const char *bdf,
+							  const char *iommu_mode,
+							  const char *vf_token,
+							  int *out_ret)
+{
+	struct vfio_pci_device *device;
+
+	device = calloc(1, sizeof(*device));
+	VFIO_ASSERT_NOT_NULL(device);
+
+	device->iommu_mode = lookup_iommu_mode(iommu_mode);
+
+	if (iommu_mode_container_path(iommu_mode)) {
+		test_vfio_pci_container_setup(device, bdf, vf_token);
+		/* The device fd will be -1 in case of mismatched tokens */
+		*out_ret = (device->fd < 0);
+	} else {
+		*out_ret = test_vfio_pci_iommufd_setup(device, bdf, vf_token);
+	}
+
+	return device;
+}
+
+static void test_vfio_pci_device_cleanup(struct vfio_pci_device *device)
+{
+	if (device->fd > 0)
+		VFIO_ASSERT_EQ(close(device->fd), 0);
+
+	if (device->iommufd) {
+		VFIO_ASSERT_EQ(close(device->iommufd), 0);
+	} else {
+		VFIO_ASSERT_EQ(close(device->group_fd), 0);
+		VFIO_ASSERT_EQ(close(device->container_fd), 0);
+	}
+
+	free(device);
+}
+
+FIXTURE(vfio_pci_sriov_uapi_test) {};
+
+FIXTURE_SETUP(vfio_pci_sriov_uapi_test)
+{
+	char vf_path[PATH_MAX] = {0};
+	char path[PATH_MAX] = {0};
+	unsigned int nr_vfs;
+	char buf[32] = {0};
+	int ret;
+	int fd;
+
+	/* Check if SR-IOV is supported by the device */
+	snprintf(path, PATH_MAX, "%s/%s/sriov_totalvfs", PCI_SYSFS_PATH, pf_dev_bdf);
+	fd = open(path, O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "SR-IOV may not be supported by the device\n");
+		exit(KSFT_SKIP);
+	}
+
+	ASSERT_GT(read(fd, buf, ARRAY_SIZE(buf)), 0);
+	ASSERT_EQ(close(fd), 0);
+	nr_vfs = strtoul(buf, NULL, 0);
+	if (nr_vfs < 0) {
+		fprintf(stderr, "SR-IOV may not be supported by the device\n");
+		exit(KSFT_SKIP);
+	}
+
+	/* Setup VFs, if already not done */
+	snprintf(path, PATH_MAX, "%s/%s/sriov_numvfs", PCI_SYSFS_PATH, pf_dev_bdf);
+	ASSERT_GT(fd = open(path, O_RDWR), 0);
+	ASSERT_GT(read(fd, buf, ARRAY_SIZE(buf)), 0);
+	nr_vfs = strtoul(buf, NULL, 0);
+	if (nr_vfs == 0)
+		ASSERT_EQ(write(fd, "1", 1), 1);
+	ASSERT_EQ(close(fd), 0);
+
+	/* Get the BDF of the first VF */
+	snprintf(path, PATH_MAX, "%s/%s/virtfn0", PCI_SYSFS_PATH, pf_dev_bdf);
+	ret = readlink(path, vf_path, PATH_MAX);
+	ASSERT_NE(ret, -1);
+	ret = sscanf(basename(vf_path), "%s", vf_dev_bdf);
+	ASSERT_EQ(ret, 1);
+}
+
+FIXTURE_TEARDOWN(vfio_pci_sriov_uapi_test)
+{
+}
+
+FIXTURE_VARIANT(vfio_pci_sriov_uapi_test) {
+	const char *iommu_mode;
+	char *vf_token;
+};
+
+#define FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode, _name, _vf_token)		\
+FIXTURE_VARIANT_ADD(vfio_pci_sriov_uapi_test, _iommu_mode ## _ ## _name) {	\
+	.iommu_mode = #_iommu_mode,						\
+	.vf_token = (_vf_token),						\
+}
+
+FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(same_uuid, UUID_1);
+FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(diff_uuid, UUID_2);
+FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES(null_uuid, NULL);
+
+/*
+ * PF's token is always set with UUID_1 and VF's token is rotated with
+ * various tokens (including UUID_1 and NULL).
+ * This asserts if the VF device is successfully created for a match
+ * in the token or actually fails during a mismatch.
+ */
+#define ASSERT_VF_CREATION(_ret) do {				\
+	if (variant->vf_token == NULL ||			\
+	    strcmp(UUID_1, variant->vf_token)) {		\
+	    ASSERT_NE((_ret), 0);				\
+	} else {						\
+	    ASSERT_EQ((_ret), 0);				\
+	}							\
+} while (0)
+
+/*
+ * Validate if the UAPI handles correctly and incorrectly set token on the VF.
+ */
+TEST_F(vfio_pci_sriov_uapi_test, init_token_match)
+{
+	int ret;
+
+	pf_device = test_vfio_pci_device_init(pf_dev_bdf, variant->iommu_mode,
+					      UUID_1, &ret);
+	vf_device = test_vfio_pci_device_init(vf_dev_bdf, variant->iommu_mode,
+					      variant->vf_token, &ret);
+
+	ASSERT_VF_CREATION(ret);
+
+	test_vfio_pci_device_cleanup(vf_device);
+	test_vfio_pci_device_cleanup(pf_device);
+}
+
+/*
+ * After setting a token on the PF, validate if the VF can still set the
+ * expected token.
+ */
+TEST_F(vfio_pci_sriov_uapi_test, pf_early_close)
+{
+	int ret;
+
+	pf_device = test_vfio_pci_device_init(pf_dev_bdf, variant->iommu_mode,
+					      UUID_1, &ret);
+	test_vfio_pci_device_cleanup(pf_device);
+
+	vf_device = test_vfio_pci_device_init(vf_dev_bdf, variant->iommu_mode,
+					      variant->vf_token, &ret);
+
+	ASSERT_VF_CREATION(ret);
+
+	test_vfio_pci_device_cleanup(vf_device);
+}
+
+/*
+ * After PF device init, override the exsiting token and validate if the newly
+ * set token is the one that's active.
+ */
+TEST_F(vfio_pci_sriov_uapi_test, override_token)
+{
+	int ret;
+
+	pf_device = test_vfio_pci_device_init(pf_dev_bdf, variant->iommu_mode,
+					      UUID_2, &ret);
+	vfio_device_set_vf_token(pf_device->fd, UUID_1);
+
+	vf_device = test_vfio_pci_device_init(vf_dev_bdf, variant->iommu_mode,
+					      variant->vf_token, &ret);
+
+	ASSERT_VF_CREATION(ret);
+
+	test_vfio_pci_device_cleanup(vf_device);
+	test_vfio_pci_device_cleanup(pf_device);
+}
+
+int main(int argc, char *argv[])
+{
+	pf_dev_bdf = vfio_selftests_get_bdf(&argc, argv);
+	return test_harness_run(argc, argv);
+}
-- 
2.51.2.997.g839fc31de9-goog