177 lines
7.2 KiB
Python
177 lines
7.2 KiB
Python
# Copyright 2016 Andreas Florath (andreas@florath.net)
|
|
#
|
|
# 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 logging
|
|
import os
|
|
|
|
from subprocess import CalledProcessError
|
|
|
|
from diskimage_builder.block_device.exception import \
|
|
BlockDeviceSetupException
|
|
from diskimage_builder.block_device.level1.mbr import MBR
|
|
from diskimage_builder.block_device.level1.partition import PartitionNode
|
|
from diskimage_builder.block_device.plugin import PluginBase
|
|
from diskimage_builder.block_device.utils import exec_sudo
|
|
from diskimage_builder.block_device.utils import parse_abs_size_spec
|
|
from diskimage_builder.block_device.utils import parse_rel_size_spec
|
|
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class Partitioning(PluginBase):
|
|
|
|
def __init__(self, config, default_config):
|
|
logger.debug("Creating Partitioning object; config [%s]", config)
|
|
super(Partitioning, self).__init__()
|
|
|
|
# Because using multiple partitions of one base is done
|
|
# within one object, there is the need to store a flag if the
|
|
# creation of the partitions was already done.
|
|
self.already_created = False
|
|
|
|
# Parameter check
|
|
if 'base' not in config:
|
|
raise BlockDeviceSetupException("Partitioning config needs 'base'")
|
|
self.base = config['base']
|
|
|
|
if 'partitions' not in config:
|
|
raise BlockDeviceSetupException(
|
|
"Partitioning config needs 'partitions'")
|
|
|
|
if 'label' not in config:
|
|
raise BlockDeviceSetupException(
|
|
"Partitioning config needs 'label'")
|
|
self.label = config['label']
|
|
if self.label not in ("mbr", ):
|
|
raise BlockDeviceSetupException("Label must be 'mbr'")
|
|
|
|
# It is VERY important to get the alignment correct. If this
|
|
# is not correct, the disk performance might be very poor.
|
|
# Example: In some tests a 'off by one' leads to a write
|
|
# performance of 30% compared to a correctly aligned
|
|
# partition.
|
|
# The problem for DIB is, that it cannot assume that the host
|
|
# system uses the same IO sizes as the target system,
|
|
# therefore here a fixed approach (as used in all modern
|
|
# systems with large disks) is used. The partitions are
|
|
# aligned to 1MiB (which are about 2048 times 512 bytes
|
|
# blocks)
|
|
self.align = 1024 * 1024 # 1MiB as default
|
|
if 'align' in config:
|
|
self.align = parse_abs_size_spec(config['align'])
|
|
|
|
self.partitions = []
|
|
prev_partition = None
|
|
|
|
for part_cfg in config['partitions']:
|
|
np = PartitionNode(part_cfg, self, prev_partition)
|
|
self.partitions.append(np)
|
|
prev_partition = np
|
|
|
|
def get_nodes(self):
|
|
# return the list of partitions
|
|
return self.partitions
|
|
|
|
def _size_of_block_dev(self, dev):
|
|
with open(dev, "r") as fd:
|
|
fd.seek(0, 2)
|
|
return fd.tell()
|
|
|
|
def _all_part_devices_exist(self, expected_part_devices):
|
|
for part_device in expected_part_devices:
|
|
logger.debug("Checking if partition device [%s] exists",
|
|
part_device)
|
|
if not os.path.exists(part_device):
|
|
logger.info("Partition device [%s] does not exists",
|
|
part_device)
|
|
return False
|
|
logger.debug("Partition already exists [%s]", part_device)
|
|
return True
|
|
|
|
def _notify_os_of_partition_changes(self, device_path, partition_devices):
|
|
"""Notify of of partition table changes
|
|
|
|
There is the need to call some programs to inform the operating
|
|
system of partition tables changes.
|
|
These calls are highly distribution and version specific. Here
|
|
a couple of different methods are used to get the best result.
|
|
"""
|
|
try:
|
|
exec_sudo(["partprobe", device_path])
|
|
exec_sudo(["udevadm", "settle"])
|
|
except CalledProcessError as e:
|
|
logger.info("Ignoring settling failure: %s", e)
|
|
pass
|
|
|
|
if self._all_part_devices_exist(partition_devices):
|
|
return
|
|
# If running inside Docker, make our nodes manually, because udev
|
|
# will not be working.
|
|
if os.path.exists("/.dockerenv"):
|
|
# kpartx cannot run in sync mode in docker.
|
|
exec_sudo(["kpartx", "-av", device_path])
|
|
exec_sudo(["dmsetup", "--noudevsync", "mknodes"])
|
|
return
|
|
|
|
exec_sudo(["kpartx", "-avs", device_path])
|
|
|
|
def create(self, result, rollback):
|
|
# not this is NOT a node and this is not called directly! The
|
|
# create() calls in the partition nodes this plugin has
|
|
# created are calling back into this.
|
|
image_path = result['blockdev'][self.base]['image']
|
|
device_path = result['blockdev'][self.base]['device']
|
|
logger.info("Creating partition on [%s] [%s]",
|
|
self.base, image_path)
|
|
|
|
# This is a bit of a hack. Each of the partitions is actually
|
|
# in the graph, so for every partition we get a create() call
|
|
# as the walk happens. But we only need to create the
|
|
# partition table once...
|
|
if self.already_created:
|
|
logger.info("Not creating the partitions a second time.")
|
|
return
|
|
|
|
assert self.label == 'mbr'
|
|
|
|
partition_devices = set()
|
|
disk_size = self._size_of_block_dev(image_path)
|
|
with MBR(image_path, disk_size, self.align) as part_impl:
|
|
for part_cfg in self.partitions:
|
|
part_name = part_cfg.get_name()
|
|
part_bootflag = PartitionNode.flag_boot \
|
|
in part_cfg.get_flags()
|
|
part_primary = PartitionNode.flag_primary \
|
|
in part_cfg.get_flags()
|
|
part_size = part_cfg.get_size()
|
|
part_free = part_impl.free()
|
|
part_type = part_cfg.get_type()
|
|
logger.debug("Not partitioned space [%d]", part_free)
|
|
part_size = parse_rel_size_spec(part_size,
|
|
part_free)[1]
|
|
part_no \
|
|
= part_impl.add_partition(part_primary, part_bootflag,
|
|
part_size, part_type)
|
|
logger.debug("Create partition [%s] [%d]",
|
|
part_name, part_no)
|
|
partition_device_name = device_path + "p%d" % part_no
|
|
result['blockdev'][part_name] \
|
|
= {'device': partition_device_name}
|
|
partition_devices.add(partition_device_name)
|
|
|
|
self.already_created = True
|
|
self._notify_os_of_partition_changes(device_path, partition_devices)
|
|
return
|