Re: [PATCH v8 4/8] vfio: selftests: Extend container/iommufd setup for passing vf_token

[Vipin Sharma <vipinsh@google.com>]

On Tue, May 05, 2026 at 09:28:34PM +0000, Raghavendra Rao Ananta wrote:
> 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 e26917ee169c5..4437f04660089 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 80e8e5bebd7ca..e59b6689f4576 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>
>  
> @@ -222,7 +224,27 @@ 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;
> @@ -240,8 +262,7 @@ 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)
> @@ -302,12 +323,20 @@ 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);
>  }
> @@ -322,7 +351,8 @@ 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);
>  
> @@ -330,7 +360,7 @@ 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);
>  }
>  
> @@ -346,9 +376,9 @@ 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);
> -- 
> 2.54.0.545.g6539524ca2-goog
> 
Reviewed-by: Vipin Sharma <vipinsh@google.com>