ironic-python-agent/ironic_python_agent/raid_utils.py

447 lines
18 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 copy
import re
import shlex
from ironic_lib import utils as il_utils
from oslo_concurrency import processutils
from oslo_log import log as logging
from ironic_python_agent import disk_utils
from ironic_python_agent import errors
from ironic_python_agent import utils
LOG = logging.getLogger(__name__)
# NOTE(dtantsur): 550 MiB is used by DIB and seems a common guidance:
# https://www.rodsbooks.com/efi-bootloaders/principles.html
ESP_SIZE_MIB = 550
# NOTE(rpittau) The partition number used to create a raid device.
# Could be changed to variable if we ever decide, for example to create
# some additional partitions (e.g. boot partitions), so md0 is on the
# partition 1, md1 on the partition 2, and so on.
RAID_PARTITION = 1
def get_block_devices_for_raid(block_devices, logical_disks):
"""Get block devices that are involved in the RAID configuration.
This call does two things:
* Collect all block devices that are involved in RAID.
* Update each logical disks with suitable block devices.
"""
serialized_devs = [dev.serialize() for dev in block_devices]
# NOTE(dtantsur): we're going to modify the structure, so make a copy
logical_disks = copy.deepcopy(logical_disks)
# NOTE(dtantsur): using a list here is less efficient than a set, but
# allows keeping the original ordering.
result = []
for logical_disk in logical_disks:
if logical_disk.get('physical_disks'):
matching = []
for phys_disk in logical_disk['physical_disks']:
candidates = [
dev['name'] for dev in il_utils.find_devices_by_hints(
serialized_devs, phys_disk)
]
if not candidates:
raise errors.SoftwareRAIDError(
"No candidates for physical disk %(hints)s "
"from the list %(devices)s"
% {'hints': phys_disk, 'devices': serialized_devs})
try:
matching.append(next(x for x in candidates
if x not in matching))
except StopIteration:
raise errors.SoftwareRAIDError(
"No candidates left for physical disk %(hints)s "
"from the list %(candidates)s after picking "
"%(matching)s for previous volumes"
% {'hints': phys_disk, 'matching': matching,
'candidates': candidates})
else:
# This RAID device spans all disks.
matching = [dev.name for dev in block_devices]
# Update the result keeping the ordering and avoiding duplicates.
result.extend(disk for disk in matching if disk not in result)
logical_disk['block_devices'] = matching
return result, logical_disks
def calculate_raid_start(target_boot_mode, partition_table_type, dev_name):
"""Define the start sector for the raid partition.
:param target_boot_mode: the node boot mode.
:param partition_table_type: the node partition label, gpt or msdos.
:param dev_name: block device in the raid configuration.
:return: The start sector for the raid partition.
"""
# TODO(rg): TBD, several options regarding boot part slots here:
# 1. Create boot partitions in prevision
# 2. Just leave space
# 3. Do nothing: rely on the caller to specify target_raid_config
# correctly according to what they intend to do (e.g. not set MAX
# if they know they will need some space for bios boot or efi
# parts). Best option imo, if we accept that the target volume
# granularity is GiB, so you lose up to 1GiB just for a bios boot
# partition...
if target_boot_mode == 'uefi':
# Leave 551MiB - start_sector s for the esp (approx 550 MiB)
# TODO(dtantsur): 550 MiB is a waste in most cases, make it
# configurable?
raid_start = '%sMiB' % (ESP_SIZE_MIB + 1)
else:
if partition_table_type == 'gpt':
# Leave 8MiB - start_sector s (approx 7MiB)
# for the bios boot partition or the ppc prepboot part
# This should avoid grub errors saying that it cannot
# install boot stage 1.5/2 (since the mbr gap does not
# exist on disk holders with gpt tables)
raid_start = '8MiB'
else:
# sgdisk works fine for display data on mbr tables too
out, _u = utils.execute('sgdisk', '-F', dev_name)
raid_start = "{}s".format(out.splitlines()[-1])
return raid_start
def calc_raid_partition_sectors(psize, start):
"""Calculates end sector and converts start and end sectors including
the unit of measure, compatible with parted.
:param psize: size of the raid partition
:param start: start sector of the raid partition in integer format
:return: start and end sector in parted compatible format, end sector
as integer
"""
if isinstance(start, int):
start_str = '%dGiB' % start
else:
start_str = start
if psize == -1:
end_str = '-1'
end = '-1'
else:
if isinstance(start, int):
end = start + psize
else:
# First partition case, start is sth like 2048s
end = psize
end_str = '%dGiB' % end
return start_str, end_str, end
def create_raid_partition_tables(block_devices, partition_table_type,
target_boot_mode):
"""Creates partition tables in all disks in a RAID configuration and
reports the starting sector for each partition on each disk.
:param block_devices: disks where we want to create the partition tables.
:param partition_table_type: type of partition table to create, for example
gpt or msdos.
:param target_boot_mode: the node selected boot mode, for example uefi
or bios.
:return: a dictionary of devices and the start of the corresponding
partition.
"""
parted_start_dict = {}
for dev_name in block_devices:
utils.create_partition_table(dev_name, partition_table_type)
parted_start_dict[dev_name] = calculate_raid_start(
target_boot_mode, partition_table_type, dev_name)
return parted_start_dict
def _get_actual_component_devices(raid_device):
"""Get the component devices of a Software RAID device.
Examine an md device and return its constituent devices.
:param raid_device: A Software RAID block device name.
:returns: A list of the component devices.
"""
if not raid_device:
return []
try:
out, _ = utils.execute('mdadm', '--detail', raid_device,
use_standard_locale=True)
except processutils.ProcessExecutionError as e:
LOG.warning('Could not get component devices of %(dev)s: %(err)s',
{'dev': raid_device, 'err': e})
return []
component_devices = []
lines = out.splitlines()
# the first line contains the md device itself
for line in lines[1:]:
device = re.findall(r'/dev/\w+', line)
component_devices += device
return component_devices
def create_raid_device(index, logical_disk):
"""Create a raid device.
:param index: the index of the resulting md device.
:param logical_disk: the logical disk containing the devices used to
crete the raid.
:raise: errors.SoftwareRAIDError if not able to create the raid device
or fails to re-add a device to a raid.
"""
md_device = '/dev/md%d' % index
component_devices = []
for device in logical_disk['block_devices']:
# The partition delimiter for all common harddrives (sd[a-z]+)
part_delimiter = ''
if 'nvme' in device:
part_delimiter = 'p'
component_devices.append(
device + part_delimiter + str(index + RAID_PARTITION))
raid_level = logical_disk['raid_level']
# The schema check allows '1+0', but mdadm knows it as '10'.
if raid_level == '1+0':
raid_level = '10'
volume_name = logical_disk.get('volume_name')
try:
if volume_name is None:
volume_name = md_device
LOG.debug("Creating md device %(dev)s with name %(name)s"
"on %(comp)s",
{'dev': md_device, 'name': volume_name,
'comp': component_devices})
utils.execute('mdadm', '--create', md_device, '--force',
'--run', '--metadata=1', '--level', raid_level,
'--name', volume_name, '--raid-devices',
len(component_devices), *component_devices)
except processutils.ProcessExecutionError as e:
msg = "Failed to create md device {} on {}: {}".format(
md_device, ' '.join(component_devices), e)
raise errors.SoftwareRAIDError(msg)
# check for missing devices and re-add them
actual_components = _get_actual_component_devices(md_device)
missing = set(component_devices) - set(actual_components)
for dev in missing:
try:
LOG.warning('Found %(device)s to be missing from %(md)s '
'... re-adding!',
{'device': dev, 'md': md_device})
utils.execute('mdadm', '--add', md_device, dev,
attempts=3, delay_on_retry=True)
except processutils.ProcessExecutionError as e:
msg = "Failed re-add {} to {}: {}".format(
dev, md_device, e)
raise errors.SoftwareRAIDError(msg)
def get_next_free_raid_device():
"""Get a device name that is still free."""
from ironic_python_agent import hardware
names = {dev.name for dev in
hardware.dispatch_to_managers('list_block_devices')}
for idx in range(128):
name = f'/dev/md{idx}'
if name not in names:
return name
raise errors.SoftwareRAIDError("No free md (RAID) devices are left")
def get_volume_name_of_raid_device(raid_device):
"""Get the volume name of a RAID device
:param raid_device: A Software RAID block device name.
:returns: volume name of the device, or None
"""
if not raid_device:
return None
try:
out, _ = utils.execute('mdadm', '--detail', raid_device,
use_standard_locale=True)
except processutils.ProcessExecutionError as e:
LOG.warning('Could not retrieve the volume name of %(dev)s: %(err)s',
{'dev': raid_device, 'err': e})
return None
lines = out.splitlines()
for line in lines:
if re.search(r'Name', line) is not None:
split_array = line.split(':')
# expecting format:
# Name : <host>:name (optional comment)
if len(split_array) == 3:
candidate = split_array[2]
else:
return None
# if name is followed by some other text
# such as (local to host <domain>) remove
# everything after " "
if " " in candidate:
candidate = candidate.split(" ")[0]
volume_name = candidate
return volume_name
return None
# TODO(rg): handle PreP boot parts relocation as well
def prepare_boot_partitions_for_softraid(device, holders, efi_part,
target_boot_mode):
"""Prepare boot partitions when relevant.
Create either a RAIDed EFI partition or bios boot partitions for software
RAID, according to both target boot mode and disk holders partition table
types.
:param device: the softraid device path
:param holders: the softraid drive members
:param efi_part: when relevant the efi partition coming from the image
deployed on softraid device, can be/is often None
:param target_boot_mode: target boot mode can be bios/uefi/None
or anything else for unspecified
:returns: the path to the ESP md device when target boot mode is uefi,
nothing otherwise.
"""
# Actually any fat partition could be a candidate. Let's assume the
# partition also has the esp flag
if target_boot_mode == 'uefi':
if not efi_part:
LOG.debug("No explicit EFI partition provided. Scanning for any "
"EFI partition located on software RAID device %s to "
"be relocated",
device)
# NOTE: for whole disk images, no efi part uuid will be provided.
# Let's try to scan for esp on the root softraid device. If not
# found, it's fine in most cases to just create an empty esp and
# let grub handle the magic.
efi_part = disk_utils.find_efi_partition(device)
if efi_part:
efi_part = '{}p{}'.format(device, efi_part['number'])
# check if we have a RAIDed ESP already
md_device = find_esp_raid()
if md_device:
LOG.info("Found RAIDed ESP %s, skip creation", md_device)
else:
LOG.info("Creating EFI partitions on software RAID holder disks")
# We know that we kept this space when configuring raid,see
# hardware.GenericHardwareManager.create_configuration.
# We could also directly get the EFI partition size.
partsize_mib = ESP_SIZE_MIB
partlabel_prefix = 'uefi-holder-'
efi_partitions = []
for number, holder in enumerate(holders):
# NOTE: see utils.get_partition_table_type_from_specs
# for uefi we know that we have setup a gpt partition table,
# sgdisk can be used to edit table, more user friendly
# for alignment and relative offsets
partlabel = '{}{}'.format(partlabel_prefix, number)
out, _u = utils.execute('sgdisk', '-F', holder)
start_sector = '{}s'.format(out.splitlines()[-1].strip())
out, _u = utils.execute(
'sgdisk', '-n', '0:{}:+{}MiB'.format(start_sector,
partsize_mib),
'-t', '0:ef00', '-c', '0:{}'.format(partlabel), holder)
# Refresh part table
utils.execute("partprobe")
utils.execute("blkid")
target_part, _u = utils.execute(
"blkid", "-l", "-t", "PARTLABEL={}".format(partlabel),
holder)
target_part = target_part.splitlines()[-1].split(':', 1)[0]
efi_partitions.append(target_part)
LOG.debug("EFI partition %s created on holder disk %s",
target_part, holder)
# RAID the ESPs, metadata=1.0 is mandatory to be able to boot
md_device = get_next_free_raid_device()
LOG.debug("Creating md device %(md_device)s for the ESPs "
"on %(efi_partitions)s",
{'md_device': md_device,
'efi_partitions': efi_partitions})
utils.execute('mdadm', '--create', md_device, '--force',
'--run', '--metadata=1.0', '--level', '1',
'--name', 'esp', '--raid-devices',
len(efi_partitions),
*efi_partitions)
disk_utils.trigger_device_rescan(md_device)
if efi_part:
# Blockdev copy the source ESP and erase it
LOG.debug("Relocating EFI %s to %s", efi_part, md_device)
utils.execute('cp', efi_part, md_device)
LOG.debug("Erasing EFI partition %s", efi_part)
utils.execute('wipefs', '-a', efi_part)
else:
fslabel = 'efi-part'
il_utils.mkfs(fs='vfat', path=md_device, label=fslabel)
return md_device
elif target_boot_mode == 'bios':
partlabel_prefix = 'bios-boot-part-'
for number, holder in enumerate(holders):
label = disk_utils.get_partition_table_type(holder)
if label == 'gpt':
LOG.debug("Creating bios boot partition on disk holder %s",
holder)
out, _u = utils.execute('sgdisk', '-F', holder)
start_sector = '{}s'.format(out.splitlines()[-1].strip())
partlabel = '{}{}'.format(partlabel_prefix, number)
out, _u = utils.execute(
'sgdisk', '-n', '0:{}:+2MiB'.format(start_sector),
'-t', '0:ef02', '-c', '0:{}'.format(partlabel), holder)
# Q: MBR case, could we dd the boot code from the softraid
# (446 first bytes) if we detect a bootloader with
# _is_bootloader_loaded?
# A: This won't work. Because it includes the address on the
# disk, as in virtual disk, where to load the data from.
# Since there is a structural difference, this means it will
# fail.
def find_esp_raid():
"""Find the ESP md device in case of a rebuild."""
# find devices of type 'RAID1' and fstype 'VFAT'
lsblk = utils.execute('lsblk', '-PbioNAME,TYPE,FSTYPE')
report = lsblk[0]
for line in report.split('\n'):
dev = {}
vals = shlex.split(line)
for key, val in (v.split('=', 1) for v in vals):
dev[key] = val.strip()
if dev.get('TYPE') == 'raid1' and dev.get('FSTYPE') == 'vfat':
return '/dev/' + dev.get('NAME')