[PATCH v7 4/8] vfio: selftests: Extend container/iommufd setup for passing vf_token

Raghavendra Rao Ananta
2026-04-02T17:31:08Z

A UUID is normally set as a vf_token to correspond the VFs with the
PFs, if they are both bound by the vfio-pci driver. This is true for
iommufd-based approach and container-based approach. The token can be
set either during device creation (VFIO_GROUP_GET_DEVICE_FD) in
container-based approach or during iommu bind (VFIO_DEVICE_BIND_IOMMUFD)
in the iommu-fd case. Hence extend the functions,
vfio_pci_iommufd_setup() and vfio_pci_container_setup(), to accept
vf_token as an (optional) argument and handle the necessary setup.

No functional changes are expected.

Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
---
tools/testing/selftests/vfio/Makefile | 2 +
.../selftests/vfio/lib/vfio_pci_device.c | 46 +++++++++++++++----
2 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/vfio/Makefile b/tools/testing/selftests/vfio/Makefile
index 6a9ac6dd32cb6..f27ed18070f14 100644
--- a/tools/testing/selftests/vfio/Makefile
+++ b/tools/testing/selftests/vfio/Makefile
@@ -28,6 +28,8 @@ CFLAGS += $(EXTRA_CFLAGS)

LDFLAGS += -pthread

+LDLIBS += -luuid
+
$(TEST_GEN_PROGS): %: %.o $(LIBVFIO_O)
$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $< $(LIBVFIO_O) $(LDLIBS) -o $@

diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c b/tools/testing/selftests/vfio/lib/vfio_pci_device.c
index 82f255f0486dc..dc8b37df8d1f1 100644
--- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c
+++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c
@@ -22,6 +22,8 @@
#include <linux/types.h>
#include <linux/vfio.h>

+#include <uuid/uuid.h>
+
#include "kselftest.h"
#include <libvfio.h>

@@ -220,7 +222,27 @@ static void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf
ioctl_assert(device->group_fd, VFIO_GROUP_SET_CONTAINER, &device->iommu->container_fd);
}

-static void vfio_pci_container_setup(struct vfio_pci_device *device, const char *bdf)
+static void vfio_pci_group_get_device_fd(struct vfio_pci_device *device,
+ const char *bdf, const char *vf_token)
+{
+ char arg[64];
+
+ /*
+ * If a vf_token exists, argument to VFIO_GROUP_GET_DEVICE_FD
+ * will be in the form of the following example:
+ * "0000:04:10.0 vf_token=bd8d9d2b-5a5f-4f5a-a211-f591514ba1f3"
+ */
+ if (vf_token)
+ snprintf_assert(arg, ARRAY_SIZE(arg), "%s vf_token=%s", bdf, vf_token);
+ else
+ snprintf_assert(arg, ARRAY_SIZE(arg), "%s", bdf);
+
+ device->fd = ioctl(device->group_fd, VFIO_GROUP_GET_DEVICE_FD, arg);
+ VFIO_ASSERT_GE(device->fd, 0);
+}
+
+static void vfio_pci_container_setup(struct vfio_pci_device *device,
+ const char *bdf, const char *vf_token)
{
struct iommu *iommu = device->iommu;
unsigned long iommu_type = iommu->mode->iommu_type;
@@ -238,8 +260,7 @@ static void vfio_pci_container_setup(struct vfio_pci_device *device, const char
*/
(void)ioctl(iommu->container_fd, VFIO_SET_IOMMU, (void *)iommu_type);

- device->fd = ioctl(device->group_fd, VFIO_GROUP_GET_DEVICE_FD, bdf);
- VFIO_ASSERT_GE(device->fd, 0);
+ vfio_pci_group_get_device_fd(device, bdf, vf_token);
}

static void vfio_pci_device_setup(struct vfio_pci_device *device)
@@ -300,12 +321,20 @@ const char *vfio_pci_get_cdev_path(const char *bdf)
return cdev_path;
}

-static void vfio_device_bind_iommufd(int device_fd, int iommufd)
+static void vfio_device_bind_iommufd(int device_fd, int iommufd,
+ const char *vf_token)
{
struct vfio_device_bind_iommufd args = {
.argsz = sizeof(args),
.iommufd = iommufd,
};
+ uuid_t token_uuid;
+
+ if (vf_token) {
+ VFIO_ASSERT_EQ(uuid_parse(vf_token, token_uuid), 0);
+ args.flags |= VFIO_DEVICE_BIND_FLAG_TOKEN;
+ args.token_uuid_ptr = (u64)token_uuid;
+ }

ioctl_assert(device_fd, VFIO_DEVICE_BIND_IOMMUFD, &args);
}
@@ -320,7 +349,8 @@ static void vfio_device_attach_iommufd_pt(int device_fd, u32 pt_id)
ioctl_assert(device_fd, VFIO_DEVICE_ATTACH_IOMMUFD_PT, &args);
}

-static void vfio_pci_iommufd_setup(struct vfio_pci_device *device, const char *bdf)
+static void vfio_pci_iommufd_setup(struct vfio_pci_device *device,
+ const char *bdf, const char *vf_token)
{
const char *cdev_path = vfio_pci_get_cdev_path(bdf);

@@ -328,7 +358,7 @@ static void vfio_pci_iommufd_setup(struct vfio_pci_device *device, const char *b
VFIO_ASSERT_GE(device->fd, 0);
free((void *)cdev_path);

- vfio_device_bind_iommufd(device->fd, device->iommu->iommufd);
+ vfio_device_bind_iommufd(device->fd, device->iommu->iommufd, vf_token);
vfio_device_attach_iommufd_pt(device->fd, device->iommu->ioas_id);
}

@@ -344,9 +374,9 @@ struct vfio_pci_device *vfio_pci_device_init(const char *bdf, struct iommu *iomm
device->bdf = bdf;

if (iommu->mode->container_path)
- vfio_pci_container_setup(device, bdf);
+ vfio_pci_container_setup(device, bdf, NULL);
else
- vfio_pci_iommufd_setup(device, bdf);
+ vfio_pci_iommufd_setup(device, bdf, NULL);

vfio_pci_device_setup(device);
vfio_pci_driver_probe(device);
--
2.53.0.1213.gd9a14994de-goog