Re: [PATCH v2 4/6] vfio: selftests: Export more vfio_pci functions

[David Matlack <dmatlack@google.com>]

On 2025-12-10 06:14 PM, Raghavendra Rao Ananta wrote:

shotlog nit: "Expose more vfio_pci_device functions"

> Refactor and make the functions called under device initialization
> public. A later patch adds a test that calls these functions to validate
> the UAPI of SR-IOV devices. Opportunistically, to test the success
> and failure cases of the UAPI, split the functions dealing with
> VFIO_GROUP_GET_DEVICE_FD and VFIO_DEVICE_BIND_IOMMUFD into a core
> function and another one that asserts the ioctl. The former will be
> used for testing the SR-IOV UAPI, hence only export these.
> 
> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
> ---
>  .../lib/include/libvfio/vfio_pci_device.h     |  7 +++
>  .../selftests/vfio/lib/vfio_pci_device.c      | 44 ++++++++++++++-----
>  2 files changed, 39 insertions(+), 12 deletions(-)
> 
> diff --git a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
> index 2858885a89bbb..6186ca463ca6e 100644
> --- a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
> +++ b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
> @@ -122,4 +122,11 @@ static inline bool vfio_pci_device_match(struct vfio_pci_device *device,
>  
>  const char *vfio_pci_get_cdev_path(const char *bdf);
>  
> +void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf);
> +void __vfio_pci_group_get_device_fd(struct vfio_pci_device *device,
> +				    const char *bdf, const char *vf_token);
> +void vfio_container_set_iommu(struct vfio_pci_device *device);
> +void vfio_pci_iommufd_cdev_open(struct vfio_pci_device *device, const char *bdf);
> +int __vfio_device_bind_iommufd(int device_fd, int iommufd, const char *vf_token);
> +
>  #endif /* SELFTESTS_VFIO_LIB_INCLUDE_LIBVFIO_VFIO_PCI_DEVICE_H */
> diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c b/tools/testing/selftests/vfio/lib/vfio_pci_device.c
> index ac9a5244ddc46..208da2704d9e2 100644
> --- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c
> +++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c
> @@ -180,7 +180,7 @@ void vfio_pci_device_reset(struct vfio_pci_device *device)
>  	ioctl_assert(device->fd, VFIO_DEVICE_RESET, NULL);
>  }
>  
> -static void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf)
> +void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf)
>  {
>  	struct vfio_group_status group_status = {
>  		.argsz = sizeof(group_status),
> @@ -200,8 +200,8 @@ 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_group_get_device_fd(struct vfio_pci_device *device,
> -					 const char *bdf, const char *vf_token)
> +void __vfio_pci_group_get_device_fd(struct vfio_pci_device *device,
> +				    const char *bdf, const char *vf_token)
>  {
>  	char arg[64] = {0};
>  
> @@ -216,18 +216,21 @@ static void vfio_pci_group_get_device_fd(struct vfio_pci_device *device,
>  		snprintf(arg, ARRAY_SIZE(arg), "%s", bdf);
>  
>  	device->fd = ioctl(device->group_fd, VFIO_GROUP_GET_DEVICE_FD, arg);
> +}
> +
> +static void vfio_pci_group_get_device_fd(struct vfio_pci_device *device,
> +					 const char *bdf, const char *vf_token)
> +{
> +	__vfio_pci_group_get_device_fd(device, bdf, vf_token);
>  	VFIO_ASSERT_GE(device->fd, 0);
>  }
>  
> -static void vfio_pci_container_setup(struct vfio_pci_device *device,
> -				     const char *bdf, const char *vf_token)
> +void vfio_container_set_iommu(struct vfio_pci_device *device)
>  {
>  	struct iommu *iommu = device->iommu;
>  	unsigned long iommu_type = iommu->mode->iommu_type;
>  	int ret;
>  
> -	vfio_pci_group_setup(device, bdf);
> -
>  	ret = ioctl(iommu->container_fd, VFIO_CHECK_EXTENSION, iommu_type);
>  	VFIO_ASSERT_GT(ret, 0, "VFIO IOMMU type %lu not supported\n", iommu_type);
>  
> @@ -237,7 +240,13 @@ static void vfio_pci_container_setup(struct vfio_pci_device *device,
>  	 * because the IOMMU type is already set.
>  	 */
>  	(void)ioctl(iommu->container_fd, VFIO_SET_IOMMU, (void *)iommu_type);
> +}
>  
> +static void vfio_pci_container_setup(struct vfio_pci_device *device,
> +				     const char *bdf, const char *vf_token)
> +{
> +	vfio_pci_group_setup(device, bdf);
> +	vfio_container_set_iommu(device);
>  	vfio_pci_group_get_device_fd(device, bdf, vf_token);
>  }
>  
> @@ -299,8 +308,7 @@ const char *vfio_pci_get_cdev_path(const char *bdf)
>  	return cdev_path;
>  }
>  
> -static void vfio_device_bind_iommufd(int device_fd, int iommufd,
> -				     const char *vf_token)
> +int __vfio_device_bind_iommufd(int device_fd, int iommufd, const char *vf_token)
>  {
>  	struct vfio_device_bind_iommufd args = {
>  		.argsz = sizeof(args),
> @@ -314,7 +322,15 @@ static void vfio_device_bind_iommufd(int device_fd, int iommufd,
>  		args.token_uuid_ptr = (u64)token_uuid;
>  	}
>  
> -	ioctl_assert(device_fd, VFIO_DEVICE_BIND_IOMMUFD, &args);
> +	return ioctl(device_fd, VFIO_DEVICE_BIND_IOMMUFD, &args);
> +}
> +
> +static void vfio_device_bind_iommufd(int device_fd, int iommufd,
> +				     const char *vf_token)
> +{
> +	int ret = __vfio_device_bind_iommufd(device_fd, iommufd, vf_token);
> +
> +	VFIO_ASSERT_EQ(ret, 0, "Failed VFIO_DEVICE_BIND_IOMMUFD ioctl\n");
>  }
>  
>  static void vfio_device_attach_iommufd_pt(int device_fd, u32 pt_id)
> @@ -327,15 +343,19 @@ 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, const char *vf_token)
> +void vfio_pci_iommufd_cdev_open(struct vfio_pci_device *device, const char *bdf)

nit: vfio_pci_cdev_open()

Opening the cdev doesn't interact with iommufd in the kernel in any way.
It's a pure VFIO operation. So having iommufd in the name here might be
confusing.

>  {
>  	const char *cdev_path = vfio_pci_get_cdev_path(bdf);
>  
>  	device->fd = open(cdev_path, O_RDWR);
>  	VFIO_ASSERT_GE(device->fd, 0);
>  	free((void *)cdev_path);
> +}
>  
> +static void vfio_pci_iommufd_setup(struct vfio_pci_device *device,
> +				   const char *bdf, const char *vf_token)
> +{
> +	vfio_pci_iommufd_cdev_open(device, bdf);
>  	vfio_device_bind_iommufd(device->fd, device->iommu->iommufd, vf_token);
>  	vfio_device_attach_iommufd_pt(device->fd, device->iommu->ioas_id);
>  }
> -- 
> 2.52.0.239.gd5f0c6e74e-goog
>