utils.py 文件源码

def get_vf_num_by_pci_address(pci_addr):
    """Get the VF number based on a VF's pci address

    A VF is associated with an VF number, which ip link command uses to
    configure it. This number can be obtained from the PCI device filesystem.
    """
    VIRTFN_RE = re.compile("virtfn(\d+)")
    virtfns_path = "/sys/bus/pci/devices/%s/physfn/virtfn*" % (pci_addr)
    vf_num = None
    try:
        for vf_path in glob.iglob(virtfns_path):
            if re.search(pci_addr, os.readlink(vf_path)):
                t = VIRTFN_RE.search(vf_path)
                vf_num = t.group(1)
                break
    except Exception:
        pass
    if vf_num is None:
        raise exception.PciDeviceNotFoundById(id=pci_addr)
    return vf_num