# 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
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 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
[docs]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
[docs]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
[docs]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 partion 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
[docs]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
[docs]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'
try:
LOG.debug("Creating md device %(dev)s on %(comp)s",
{'dev': md_device, 'comp': component_devices})
utils.execute('mdadm', '--create', md_device, '--force',
'--run', '--metadata=1', '--level', raid_level,
'--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)
