nova/nova/pci/utils.py

227 lines
7.9 KiB
Python

# Copyright (c) 2013 Intel, Inc.
# Copyright (c) 2012 OpenStack Foundation
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import glob
import os
import re
from oslo_log import log as logging
import six
from nova import exception
LOG = logging.getLogger(__name__)
PCI_VENDOR_PATTERN = "^(hex{4})$".replace("hex", "[\da-fA-F]")
_PCI_ADDRESS_PATTERN = ("^(hex{4}):(hex{2}):(hex{2}).(oct{1})$".
replace("hex", "[\da-fA-F]").
replace("oct", "[0-7]"))
_PCI_ADDRESS_REGEX = re.compile(_PCI_ADDRESS_PATTERN)
_SRIOV_TOTALVFS = "sriov_totalvfs"
def pci_device_prop_match(pci_dev, specs):
"""Check if the pci_dev meet spec requirement
Specs is a list of PCI device property requirements.
An example of device requirement that the PCI should be either:
a) Device with vendor_id as 0x8086 and product_id as 0x8259, or
b) Device with vendor_id as 0x10de and product_id as 0x10d8:
[{"vendor_id":"8086", "product_id":"8259"},
{"vendor_id":"10de", "product_id":"10d8",
"capabilities_network": ["rx", "tx", "tso", "gso"]}]
"""
def _matching_devices(spec):
for k, v in spec.items():
pci_dev_v = pci_dev.get(k)
if isinstance(v, list) and isinstance(pci_dev_v, list):
if not all(x in pci_dev.get(k) for x in v):
return False
else:
# We don't need to check case for tags in order to avoid any
# mismatch with the tags provided by users for port
# binding profile and the ones configured by operators
# with pci whitelist option.
if isinstance(v, six.string_types):
v = v.lower()
if isinstance(pci_dev_v, six.string_types):
pci_dev_v = pci_dev_v.lower()
if pci_dev_v != v:
return False
return True
return any(_matching_devices(spec) for spec in specs)
def parse_address(address):
"""Returns (domain, bus, slot, function) from PCI address that is stored in
PciDevice DB table.
"""
m = _PCI_ADDRESS_REGEX.match(address)
if not m:
raise exception.PciDeviceWrongAddressFormat(address=address)
return m.groups()
def get_pci_address_fields(pci_addr):
"""Parse a fully-specified PCI device address.
Does not validate that the components are valid hex or wildcard values.
:param pci_addr: A string of the form "<domain>:<bus>:<slot>.<function>".
:return: A 4-tuple of strings ("<domain>", "<bus>", "<slot>", "<function>")
"""
dbs, sep, func = pci_addr.partition('.')
domain, bus, slot = dbs.split(':')
return domain, bus, slot, func
def get_pci_address(domain, bus, slot, func):
"""Assembles PCI address components into a fully-specified PCI address.
Does not validate that the components are valid hex or wildcard values.
:param domain, bus, slot, func: Hex or wildcard strings.
:return: A string of the form "<domain>:<bus>:<slot>.<function>".
"""
return '%s:%s:%s.%s' % (domain, bus, slot, func)
def get_function_by_ifname(ifname):
"""Given the device name, returns the PCI address of a device
and returns True if the address is in a physical function.
"""
dev_path = "/sys/class/net/%s/device" % ifname
sriov_totalvfs = 0
if os.path.isdir(dev_path):
try:
# sriov_totalvfs contains the maximum possible VFs for this PF
with open(os.path.join(dev_path, _SRIOV_TOTALVFS)) as fd:
sriov_totalvfs = int(fd.read())
return (os.readlink(dev_path).strip("./"),
sriov_totalvfs > 0)
except (IOError, ValueError):
return os.readlink(dev_path).strip("./"), False
return None, False
def is_physical_function(domain, bus, slot, function):
dev_path = "/sys/bus/pci/devices/%(d)s:%(b)s:%(s)s.%(f)s/" % {
"d": domain, "b": bus, "s": slot, "f": function}
if os.path.isdir(dev_path):
try:
with open(dev_path + _SRIOV_TOTALVFS) as fd:
sriov_totalvfs = int(fd.read())
return sriov_totalvfs > 0
except (IOError, ValueError):
pass
return False
def _get_sysfs_netdev_path(pci_addr, pf_interface):
"""Get the sysfs path based on the PCI address of the device.
Assumes a networking device - will not check for the existence of the path.
"""
if pf_interface:
return "/sys/bus/pci/devices/%s/physfn/net" % pci_addr
return "/sys/bus/pci/devices/%s/net" % pci_addr
def get_ifname_by_pci_address(pci_addr, pf_interface=False):
"""Get the interface name based on a VF's pci address.
The returned interface name is either the parent PF's or that of the VF
itself based on the argument of pf_interface.
"""
dev_path = _get_sysfs_netdev_path(pci_addr, pf_interface)
try:
dev_info = os.listdir(dev_path)
return dev_info.pop()
except Exception:
raise exception.PciDeviceNotFoundById(id=pci_addr)
def get_mac_by_pci_address(pci_addr, pf_interface=False):
"""Get the MAC address of the nic based on its PCI address.
Raises PciDeviceNotFoundById in case the pci device is not a NIC
"""
dev_path = _get_sysfs_netdev_path(pci_addr, pf_interface)
if_name = get_ifname_by_pci_address(pci_addr, pf_interface)
addr_file = os.path.join(dev_path, if_name, 'address')
try:
with open(addr_file) as f:
mac = next(f).strip()
return mac
except (IOError, StopIteration) as e:
LOG.warning("Could not find the expected sysfs file for "
"determining the MAC address of the PCI device "
"%(addr)s. May not be a NIC. Error: %(e)s",
{'addr': pci_addr, 'e': e})
raise exception.PciDeviceNotFoundById(id=pci_addr)
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
def get_net_name_by_vf_pci_address(vfaddress):
"""Given the VF PCI address, returns the net device name.
Every VF is associated to a PCI network device. This function
returns the libvirt name given to this network device; e.g.:
<device>
<name>net_enp8s0f0_90_e2_ba_5e_a6_40</name>
...
In the libvirt parser information tree, the network device stores the
network capabilities associated to this device.
"""
try:
mac = get_mac_by_pci_address(vfaddress).split(':')
ifname = get_ifname_by_pci_address(vfaddress)
return ("net_%(ifname)s_%(mac)s" %
{'ifname': ifname, 'mac': '_'.join(mac)})
except Exception:
LOG.warning("No net device was found for VF %(vfaddress)s",
{'vfaddress': vfaddress})
return