openstack/os-vif
Code Issues Proposed changes
os-vif/vif_plug_ovs/linux_net.py
Sean Mooney 655c83d706 only disable mac ageing for ovs hybrid plug 
The mac ageing configuration on linux bridges is now
conditional and caller controlled. By default mac ageing
is unspecified and will use the kernel's default of 300
seconds. For ovs with hybrid plug we override this to
0 to prevent packet loss issue during some migration
edgecases. This change reverts disabling mac ageing
for the linux bridge plugin which was accidentally
introduced during the brctl removal via inheriting the
ovs plugin's default behavior when the bridge create
code became shared.

Change-Id: I95612352de6cdb47de98eb80c208dd1a74499d41
Closes-bug: #1837252
2019-08-07 18:54:47 +01:00

392 lines
13 KiB
Python
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# Derived from nova/network/linux_net.py
#
# Copyright (c) 2011 X.commerce, a business unit of eBay Inc.
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# 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.
"""Implements vlans, bridges using linux utilities."""
import glob
import os
import re
import sys
from os_vif.internal.ip.api import ip as ip_lib
from oslo_concurrency import processutils
from oslo_log import log as logging
from oslo_utils import excutils
from vif_plug_ovs import constants
from vif_plug_ovs import exception
from vif_plug_ovs import privsep
LOG = logging.getLogger(__name__)
VIRTFN_RE = re.compile(r"virtfn(\d+)")
# phys_port_name only contains the VF number
INT_RE = re.compile(r"^(\d+)$")
# phys_port_name contains VF## or vf##
VF_RE = re.compile(r"vf(\d+)", re.IGNORECASE)
# phys_port_name contains PF## or pf##
PF_RE = re.compile(r"pf(\d+)", re.IGNORECASE)
# bus_info (bdf) contains <bus>:<dev>.<func>
PF_FUNC_RE = re.compile(r"\.(\d+)", 0)
_SRIOV_TOTALVFS = "sriov_totalvfs"
NIC_NAME_LEN = 14
def _update_device_mtu(dev, mtu):
if not mtu:
return
if sys.platform != constants.PLATFORM_WIN32:
# Hyper-V with OVS does not support external programming of
# virtual interface MTUs via netsh or other Windows tools.
# When plugging an interface on Windows, we therefore skip
# programming the MTU and fallback to DHCP advertisement.
set_device_mtu(dev, mtu)
@privsep.vif_plug.entrypoint
def delete_net_dev(dev):
"""Delete a network device only if it exists."""
if ip_lib.exists(dev):
try:
ip_lib.delete(dev, check_exit_code=[0, 2, 254])
LOG.debug("Net device removed: '%s'", dev)
except processutils.ProcessExecutionError:
with excutils.save_and_reraise_exception():
LOG.error("Failed removing net device: '%s'", dev)
@privsep.vif_plug.entrypoint
def create_veth_pair(dev1_name, dev2_name, mtu):
"""Create a pair of veth devices with the specified names,
deleting any previous devices with those names.
"""
for dev in [dev1_name, dev2_name]:
delete_net_dev(dev)
ip_lib.add(dev1_name, 'veth', peer=dev2_name)
for dev in [dev1_name, dev2_name]:
ip_lib.set(dev, state='up')
ip_lib.set(dev, promisc='on')
_update_device_mtu(dev, mtu)
@privsep.vif_plug.entrypoint
def update_veth_pair(dev1_name, dev2_name, mtu):
"""Update a pair of veth devices with new configuration."""
for dev in [dev1_name, dev2_name]:
_update_device_mtu(dev, mtu)
def _disable_ipv6(bridge):
"""Disable ipv6 if available for bridge. Must be called from
privsep context.
"""
# NOTE(sean-k-mooney): os-vif disables ipv6 to ensure the Bridge
# does not aquire an ipv6 auto config or link local adress.
# This is required to prevent bug 1302080.
# https://bugs.launchpad.net/neutron/+bug/1302080
disv6 = ('/proc/sys/net/ipv6/conf/%s/disable_ipv6' %
bridge)
if os.path.exists(disv6):
with open(disv6, 'w') as f:
f.write('1')
# TODO(ralonsoh): extract into common module
def _arp_filtering(bridge):
"""Prevent the bridge from replying to ARP messages with machine local IPs
1. Reply only if the target IP address is local address configured on the
incoming interface.
2. Always use the best local address.
"""
arp_params = [('/proc/sys/net/ipv4/conf/%s/arp_ignore' % bridge, '1'),
('/proc/sys/net/ipv4/conf/%s/arp_announce' % bridge, '2')]
for parameter, value in arp_params:
if os.path.exists(parameter):
with open(parameter, 'w') as f:
f.write(value)
@privsep.vif_plug.entrypoint
def ensure_bridge(bridge):
if not ip_lib.exists(bridge):
# NOTE(sean-k-mooney): we set mac ageing to 0 to disable mac ageing
# on the hybrid plug bridge to avoid packet loss during live
# migration. This avoids bug #1715317 and related bug #1414559
ip_lib.add(bridge, 'bridge', ageing=0)
_disable_ipv6(bridge)
_arp_filtering(bridge)
# we bring up the bridge to allow it to switch packets
set_interface_state(bridge, 'up')
@privsep.vif_plug.entrypoint
def delete_bridge(bridge, dev):
if ip_lib.exists(bridge):
# Note(sean-k-mooney): this will detach all ports on
# the bridge before deleting the bridge.
ip_lib.delete(bridge, check_exit_code=[0, 2, 254])
# howver it will not set the detached interface down
# so we set the dev down if dev is not None and exists.
if dev and ip_lib.exists(dev):
set_interface_state(dev, "down")
@privsep.vif_plug.entrypoint
def add_bridge_port(bridge, dev):
ip_lib.set(dev, master=bridge)
@privsep.vif_plug.entrypoint
def set_device_mtu(dev, mtu):
"""Set the device MTU."""
if ip_lib.exists(dev):
ip_lib.set(dev, mtu=mtu, check_exit_code=[0, 2, 254])
@privsep.vif_plug.entrypoint
def set_interface_state(interface_name, port_state):
ip_lib.set(interface_name, state=port_state, check_exit_code=[0, 2, 254])
def _parse_vf_number(phys_port_name):
"""Parses phys_port_name and returns VF number or None.
To determine the VF number of a representor, parse phys_port_name
in the following sequence and return the first valid match. If none
match, then the representor is not for a VF.
"""
match = INT_RE.search(phys_port_name)
if match:
return match.group(1)
match = VF_RE.search(phys_port_name)
if match:
return match.group(1)
return None
def _parse_pf_number(phys_port_name):
"""Parses phys_port_name and returns PF number or None.
To determine the PF number of a representor, parse phys_port_name in
the following sequence and return the first valid match. If none
match, then the representor is not for a PF.
"""
match = PF_RE.search(phys_port_name)
if match:
return match.group(1)
return None
# This function is taken from nova/pci/utils.py
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
dev_path_file = os.path.join(dev_path, _SRIOV_TOTALVFS)
with open(dev_path_file, 'r') as fd:
sriov_totalvfs = int(fd.readline().rstrip())
return (os.readlink(dev_path).strip("./"),
sriov_totalvfs > 0)
except (IOError, ValueError):
return os.readlink(dev_path).strip("./"), False
return None, False
def _get_pf_func(pf_ifname):
"""Gets PF function number using pf_ifname and returns function
number or None.
"""
address_str, pf = get_function_by_ifname(pf_ifname)
if not address_str:
return None
match = PF_FUNC_RE.search(address_str)
if match:
return match.group(1)
return None
def get_representor_port(pf_ifname, vf_num):
"""Get the representor netdevice which is corresponding to the VF.
This method gets PF interface name and number of VF. It iterates over all
the interfaces under the PF location and looks for interface that has the
VF number in the phys_port_name. That interface is the representor for
the requested VF.
"""
pf_path = "/sys/class/net/%s" % pf_ifname
pf_sw_id_file = os.path.join(pf_path, "phys_switch_id")
pf_sw_id = None
try:
with open(pf_sw_id_file, 'r') as fd:
pf_sw_id = fd.readline().rstrip()
except (OSError, IOError):
raise exception.RepresentorNotFound(ifname=pf_ifname, vf_num=vf_num)
pf_subsystem_file = os.path.join(pf_path, "subsystem")
try:
devices = os.listdir(pf_subsystem_file)
except (OSError, IOError):
raise exception.RepresentorNotFound(ifname=pf_ifname, vf_num=vf_num)
for device in devices:
address_str, pf = get_function_by_ifname(device)
if pf:
continue
device_path = "/sys/class/net/%s" % device
device_sw_id_file = os.path.join(device_path, "phys_switch_id")
try:
with open(device_sw_id_file, 'r') as fd:
device_sw_id = fd.readline().rstrip()
except (OSError, IOError):
continue
if device_sw_id != pf_sw_id:
continue
device_port_name_file = (
os.path.join(device_path, 'phys_port_name'))
if not os.path.isfile(device_port_name_file):
continue
try:
with open(device_port_name_file, 'r') as fd:
phys_port_name = fd.readline().rstrip()
except (OSError, IOError):
continue
# If the phys_port_name of the VF-rep is of the format pfXvfY
# (or vfY@pfX), then match "X" (parent PF's func number) with
# the PCI func number of pf_ifname.
rep_parent_pf_func = _parse_pf_number(phys_port_name)
if rep_parent_pf_func is not None:
ifname_pf_func = _get_pf_func(pf_ifname)
if ifname_pf_func is None:
continue
if int(rep_parent_pf_func) != int(ifname_pf_func):
continue
representor_num = _parse_vf_number(phys_port_name)
# Note: representor_num can be 0, referring to VF0
if representor_num is None:
continue
# At this point we're confident we have a representor.
try:
if int(representor_num) == int(vf_num):
return device
except (ValueError):
continue
raise exception.RepresentorNotFound(ifname=pf_ifname, vf_num=vf_num)
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 _is_switchdev(netdev):
"""Returns True if a netdev has a readable phys_switch_id"""
try:
sw_id_file = "/sys/class/net/%s/phys_switch_id" % netdev
with open(sw_id_file, 'r') as fd:
phys_switch_id = fd.readline().rstrip()
if phys_switch_id != "" and phys_switch_id is not None:
return True
except (OSError, IOError):
return False
return False
def get_ifname_by_pci_address(pci_addr, pf_interface=False, switchdev=False):
"""Get the interface name based on a VF's pci address
:param pci_addr: the PCI address of the VF
:param pf_interface: if True, look for the netdev of the parent PF
:param switchdev: if True, ensure that phys_switch_id is valid
:returns: netdev interface name
The returned interface name is either the parent PF or that of the VF
itself based on the argument of pf_interface.
"""
dev_path = _get_sysfs_netdev_path(pci_addr, pf_interface)
# make the if statement later more readable
ignore_switchdev = not switchdev
try:
for netdev in os.listdir(dev_path):
if ignore_switchdev or _is_switchdev(netdev):
return netdev
except Exception:
raise exception.PciDeviceNotFoundById(id=pci_addr)
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.
"""
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_dpdk_representor_port_name(port_id):
devname = "vfr" + port_id
return devname[:NIC_NAME_LEN]
def get_pf_pci_from_vf(vf_pci):
"""Get physical function PCI address of a VF
:param vf_pci: the PCI address of the VF
:return: the PCI address of the PF
"""
physfn_path = os.readlink("/sys/bus/pci/devices/%s/physfn" % vf_pci)
return os.path.basename(physfn_path)
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