nova/nova/pci/devspec.py
Dmitrii Shcherbakov 0d5f8ffc2b Introduce remote_managed tag for PCI devs
PCI devices may be managed remotely from the perspective of a hypervisor
host (e.g. by a SmartNIC DPU) which means that the VF control plane is
not available to the hypervisor. Depending on the presence of a
remote_managed device attribute in the InstancePCIRequest spec and
available device types in a pool, additional processing needs to be
done:

* Filtering of devices marked as `remote_managed: "true"` in the
  whitelist configuration so that they are not used in legacy SR-IOV
  and hardware offload requests;

* Early error reporting if PFs marked as remote_managed="true" are
  present in the whitelist configuration. This is not supported
  explicitly since allocating such PFs would remove the associated
  VFs from the pool and an instance with such PF and its VFs will
  not have access to the control plane required for representor
  interface plugging at the SmartNIC DPU side. This configuration
  is not valid which is enforced in the PCIDeviceStats code.

* Checking of the presence of a card serial number in the PCI VPD
  capability of a device if it was marked as `remote_managed: "true"`
  in the whitelist. The card serial number presence is mandatory
  because it is used for identification of a host in the networking
  backend that will handle the configuration of a given PCI device at
  the remote host side (i.e. representor plugging, flow programming).

For compatibility, all devices not explicitly marked as remote_managed
in the whitelist are assumed to have remote_managed attribute set to
False.

Implements: blueprint integration-with-off-path-network-backends
Change-Id: Ic44d5e206326827d00a751da3cea67afe3929a08
2022-02-09 01:23:24 +03:00

397 lines
16 KiB
Python

#
# 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 abc
import re
import string
import typing as ty
from nova import exception
from nova.i18n import _
from nova import objects
from nova.pci.request import PCI_REMOTE_MANAGED_TAG
from nova.pci import utils
from oslo_log import log as logging
from oslo_utils import strutils
MAX_VENDOR_ID = 0xFFFF
MAX_PRODUCT_ID = 0xFFFF
MAX_FUNC = 0x7
MAX_DOMAIN = 0xFFFF
MAX_BUS = 0xFF
MAX_SLOT = 0x1F
ANY = '*'
REGEX_ANY = '.*'
LOG = logging.getLogger(__name__)
PCISpecAddressType = ty.Union[ty.Dict[str, str], str]
class PciAddressSpec(metaclass=abc.ABCMeta):
"""Abstract class for all PCI address spec styles
This class checks the address fields of the pci.passthrough_whitelist
"""
def __init__(self, pci_addr: str) -> None:
self.domain = ''
self.bus = ''
self.slot = ''
self.func = ''
@abc.abstractmethod
def match(self, pci_addr):
pass
def is_single_address(self) -> bool:
return all([
all(c in string.hexdigits for c in self.domain),
all(c in string.hexdigits for c in self.bus),
all(c in string.hexdigits for c in self.slot),
all(c in string.hexdigits for c in self.func)])
def _set_pci_dev_info(
self, prop: str, maxval: int, hex_value: str
) -> None:
a = getattr(self, prop)
if a == ANY:
return
try:
v = int(a, 16)
except ValueError:
raise exception.PciConfigInvalidWhitelist(
reason=_("property %(property)s ('%(attr)s') does not parse "
"as a hex number.") % {'property': prop, 'attr': a})
if v > maxval:
raise exception.PciConfigInvalidWhitelist(
reason=_("property %(property)s (%(attr)s) is greater than "
"the maximum allowable value (%(max)X).") %
{'property': prop, 'attr': a, 'max': maxval})
setattr(self, prop, hex_value % v)
class PhysicalPciAddress(PciAddressSpec):
"""Manages the address fields for a fully-qualified PCI address.
This function class will validate the address fields for a single
PCI device.
"""
def __init__(self, pci_addr: PCISpecAddressType) -> None:
try:
# TODO(stephenfin): Is this ever actually a string?
if isinstance(pci_addr, dict):
self.domain = pci_addr['domain']
self.bus = pci_addr['bus']
self.slot = pci_addr['slot']
self.func = pci_addr['function']
else:
self.domain, self.bus, self.slot, self.func = (
utils.get_pci_address_fields(pci_addr))
self._set_pci_dev_info('func', MAX_FUNC, '%1x')
self._set_pci_dev_info('domain', MAX_DOMAIN, '%04x')
self._set_pci_dev_info('bus', MAX_BUS, '%02x')
self._set_pci_dev_info('slot', MAX_SLOT, '%02x')
except (KeyError, ValueError):
raise exception.PciDeviceWrongAddressFormat(address=pci_addr)
def match(self, phys_pci_addr: PciAddressSpec) -> bool:
conditions = [
self.domain == phys_pci_addr.domain,
self.bus == phys_pci_addr.bus,
self.slot == phys_pci_addr.slot,
self.func == phys_pci_addr.func,
]
return all(conditions)
def __str__(self):
return f'{self.domain}:{self.bus}:{self.slot}.{self.func}'
class PciAddressGlobSpec(PciAddressSpec):
"""Manages the address fields with glob style.
This function class will validate the address fields with glob style,
check for wildcards, and insert wildcards where the field is left blank.
"""
def __init__(self, pci_addr: str) -> None:
self.domain = ANY
self.bus = ANY
self.slot = ANY
self.func = ANY
dbs, sep, func = pci_addr.partition('.')
if func:
self.func = func.strip()
self._set_pci_dev_info('func', MAX_FUNC, '%01x')
if dbs:
dbs_fields = dbs.split(':')
if len(dbs_fields) > 3:
raise exception.PciDeviceWrongAddressFormat(address=pci_addr)
# If we got a partial address like ":00.", we need to turn this
# into a domain of ANY, a bus of ANY, and a slot of 00. This code
# allows the address bus and/or domain to be left off
dbs_all = [ANY] * (3 - len(dbs_fields))
dbs_all.extend(dbs_fields)
dbs_checked = [s.strip() or ANY for s in dbs_all]
self.domain, self.bus, self.slot = dbs_checked
self._set_pci_dev_info('domain', MAX_DOMAIN, '%04x')
self._set_pci_dev_info('bus', MAX_BUS, '%02x')
self._set_pci_dev_info('slot', MAX_SLOT, '%02x')
def match(self, phys_pci_addr: PciAddressSpec) -> bool:
conditions = [
self.domain in (ANY, phys_pci_addr.domain),
self.bus in (ANY, phys_pci_addr.bus),
self.slot in (ANY, phys_pci_addr.slot),
self.func in (ANY, phys_pci_addr.func)
]
return all(conditions)
class PciAddressRegexSpec(PciAddressSpec):
"""Manages the address fields with regex style.
This function class will validate the address fields with regex style.
The validation includes check for all PCI address attributes and validate
their regex.
"""
def __init__(self, pci_addr: dict) -> None:
try:
self.domain = pci_addr.get('domain', REGEX_ANY)
self.bus = pci_addr.get('bus', REGEX_ANY)
self.slot = pci_addr.get('slot', REGEX_ANY)
self.func = pci_addr.get('function', REGEX_ANY)
self.domain_regex = re.compile(self.domain)
self.bus_regex = re.compile(self.bus)
self.slot_regex = re.compile(self.slot)
self.func_regex = re.compile(self.func)
except re.error:
raise exception.PciDeviceWrongAddressFormat(address=pci_addr)
def match(self, phys_pci_addr: PciAddressSpec) -> bool:
conditions = [
bool(self.domain_regex.match(phys_pci_addr.domain)),
bool(self.bus_regex.match(phys_pci_addr.bus)),
bool(self.slot_regex.match(phys_pci_addr.slot)),
bool(self.func_regex.match(phys_pci_addr.func))
]
return all(conditions)
class WhitelistPciAddress(object):
"""Manages the address fields of the whitelist.
This class checks the address fields of the pci.passthrough_whitelist
configuration option, validating the address fields.
Example configs:
| [pci]
| passthrough_whitelist = {"address":"*:0a:00.*",
| "physical_network":"physnet1"}
| passthrough_whitelist = {"address": {"domain": ".*",
"bus": "02",
"slot": "01",
"function": "[0-2]"},
"physical_network":"net1"}
| passthrough_whitelist = {"vendor_id":"1137","product_id":"0071"}
"""
def __init__(
self, pci_addr: PCISpecAddressType, is_physical_function: bool
) -> None:
self.is_physical_function = is_physical_function
self._init_address_fields(pci_addr)
def _check_physical_function(self) -> None:
if self.pci_address_spec.is_single_address():
self.is_physical_function = (
utils.is_physical_function(
self.pci_address_spec.domain,
self.pci_address_spec.bus,
self.pci_address_spec.slot,
self.pci_address_spec.func))
def _init_address_fields(self, pci_addr: PCISpecAddressType) -> None:
self.pci_address_spec: PciAddressSpec
if not self.is_physical_function:
if isinstance(pci_addr, str):
self.pci_address_spec = PciAddressGlobSpec(pci_addr)
elif isinstance(pci_addr, dict):
self.pci_address_spec = PciAddressRegexSpec(pci_addr)
else:
raise exception.PciDeviceWrongAddressFormat(address=pci_addr)
self._check_physical_function()
else:
self.pci_address_spec = PhysicalPciAddress(pci_addr)
def match(self, pci_addr: str, pci_phys_addr: ty.Optional[str]) -> bool:
"""Match a device to this PciAddress.
Assume this is called with a ``pci_addr`` and ``pci_phys_addr``
reported by libvirt. No attempt is made to verify if ``pci_addr`` is a
VF of ``pci_phys_addr``.
:param pci_addr: PCI address of the device to match.
:param pci_phys_addr: PCI address of the parent of the device to match
(or None if the device is not a VF).
"""
# Try to match on the parent PCI address if the PciDeviceSpec is a
# PF (sriov is available) and the device to match is a VF. This
# makes it possible to specify the PCI address of a PF in the
# pci.passthrough_whitelist to match any of its VFs' PCI addresses.
if self.is_physical_function and pci_phys_addr:
pci_phys_addr_obj = PhysicalPciAddress(pci_phys_addr)
if self.pci_address_spec.match(pci_phys_addr_obj):
return True
# Try to match on the device PCI address only.
pci_addr_obj = PhysicalPciAddress(pci_addr)
return self.pci_address_spec.match(pci_addr_obj)
class PciDeviceSpec(PciAddressSpec):
def __init__(self, dev_spec: ty.Dict[str, str]) -> None:
self.tags = dev_spec
self._init_dev_details()
def _address_obj(self) -> ty.Optional[WhitelistPciAddress]:
address_obj = None
if self.dev_name:
address_str, pf = utils.get_function_by_ifname(self.dev_name)
if not address_str:
return None
# Note(moshele): In this case we always passing a string
# of the PF pci address
address_obj = WhitelistPciAddress(address_str, pf)
else: # use self.address
address_obj = self.address
return address_obj
def _init_dev_details(self) -> None:
self.vendor_id = self.tags.pop("vendor_id", ANY)
self.product_id = self.tags.pop("product_id", ANY)
self.dev_name = self.tags.pop("devname", None)
self.address: ty.Optional[WhitelistPciAddress] = None
# Note(moshele): The address attribute can be a string or a dict.
# For glob syntax or specific pci it is a string and for regex syntax
# it is a dict. The WhitelistPciAddress class handles both types.
address = self.tags.pop("address", None)
self.vendor_id = self.vendor_id.strip()
self._set_pci_dev_info('vendor_id', MAX_VENDOR_ID, '%04x')
self._set_pci_dev_info('product_id', MAX_PRODUCT_ID, '%04x')
if address and self.dev_name:
raise exception.PciDeviceInvalidDeviceName()
if not self.dev_name:
self.address = WhitelistPciAddress(address or '*:*:*.*', False)
# PFs with remote_managed tags are explicitly not supported. If they
# are tagged as such by mistake in the whitelist Nova will
# raise an exception. The reason for excluding PFs is the lack of a way
# for an instance to access the control plane at the remote side (e.g.
# on a DPU) for managing the PF representor corresponding to the PF.
address_obj = self._address_obj()
self._remote_managed = strutils.bool_from_string(
self.tags.get(PCI_REMOTE_MANAGED_TAG))
if self._remote_managed:
if address_obj is None:
# Note that this will happen if a netdev was specified in the
# whitelist but it is not actually present on a system - in
# this case Nova is not able to look up an address by
# a netdev name.
raise exception.PciDeviceRemoteManagedNotPresent()
elif address_obj.is_physical_function:
pf_addr = str(address_obj.pci_address_spec)
vf_product_id = utils.get_vf_product_id_by_pf_addr(pf_addr)
# VF vendor IDs have to match the corresponding PF vendor IDs
# per the SR-IOV spec so we use it for matching here.
pf_vendor_id, pf_product_id = utils.get_pci_ids_by_pci_addr(
pf_addr)
# Check the actual vendor ID and VF product ID of an assumed
# VF (based on the actual PF). The VF product ID must match
# the actual one if this is a VF device spec.
if (self.product_id == vf_product_id and
self.vendor_id in (pf_vendor_id, ANY)):
pass
elif (self.product_id in (pf_product_id, ANY) and
self.vendor_id in (pf_vendor_id, ANY)):
raise exception.PciDeviceInvalidPFRemoteManaged(
address_obj.pci_address_spec)
else:
# The specified product and vendor IDs of what is supposed
# to be a VF corresponding to the PF PCI address do not
# match the actual ones for this PF. This means that the
# whitelist is invalid.
raise exception.PciConfigInvalidWhitelist(
reason=_('the specified VF vendor ID %(vendor_id)s and'
' product ID %(product_id)s do not match the'
' expected VF IDs based on the corresponding'
' PF identified by PCI address %(pf_addr)s') %
{'vendor_id': self.vendor_id,
'product_id': self.product_id,
'pf_addr': pf_addr})
def _ensure_remote_managed_dev_vpd_serial(
self, dev_dict: ty.Dict[str, ty.Any]) -> bool:
"""Ensure the presence of a serial number field in PCI VPD.
A card serial number extracted from PCI VPD is required to allow a
networking backend to identify which remote host needs to program a
given device. So if a device is tagged as remote_managed, it must
have the card serial number or be filtered out.
"""
if not self._remote_managed:
return True
card_sn = dev_dict.get('capabilities', {}).get(
'vpd', {}).get('card_serial_number')
# None or empty card_serial_number should be filtered out. That would
# mean either no serial number in the VPD (if present at all) or SN is
# an empty string which is not useful for device identification.
return bool(card_sn)
def match(self, dev_dict: ty.Dict[str, ty.Any]) -> bool:
address_obj: ty.Optional[WhitelistPciAddress] = self._address_obj()
if not address_obj:
return False
return all([
self.vendor_id in (ANY, dev_dict['vendor_id']),
self.product_id in (ANY, dev_dict['product_id']),
address_obj.match(dev_dict['address'],
dev_dict.get('parent_addr')),
self._ensure_remote_managed_dev_vpd_serial(dev_dict),
])
def match_pci_obj(self, pci_obj: 'objects.PciDevice') -> bool:
dev_dict = {
'vendor_id': pci_obj.vendor_id,
'product_id': pci_obj.product_id,
'address': pci_obj.address,
'parent_addr': pci_obj.parent_addr,
'capabilities': {
'vpd': {'card_serial_number': pci_obj.card_serial_number}}
}
return self.match(dev_dict)
def get_tags(self) -> ty.Dict[str, str]:
return self.tags