bootstrap-vz/bootstrapvz/base/fs/partitionmaps/gpt.py
2016-12-10 19:04:43 +01:00

107 lines
5 KiB
Python

from abstract import AbstractPartitionMap
from ..partitions.gpt import GPTPartition
from ..partitions.gpt_swap import GPTSwapPartition
from bootstrapvz.common.tools import log_check_call
class GPTPartitionMap(AbstractPartitionMap):
"""Represents a GPT partition map
"""
def __init__(self, data, sector_size, bootloader):
"""
:param dict data: volume.partitions part of the manifest
:param int sector_size: Sectorsize of the volume
:param str bootloader: Name of the bootloader we will use for bootstrapping
"""
from bootstrapvz.common.sectors import Sectors
# List of partitions
self.partitions = []
# Returns the last partition unless there is none
def last_partition():
return self.partitions[-1] if len(self.partitions) > 0 else None
if bootloader == 'grub':
# If we are using the grub bootloader we need to create an unformatted partition
# at the beginning of the map. Its size is 1007kb, which seems to be chosen so that
# primary gpt + grub = 1024KiB
# The 1 MiB will be subtracted later on, once we know what the subsequent partition is
from ..partitions.unformatted import UnformattedPartition
self.grub_boot = UnformattedPartition(Sectors('1MiB', sector_size), last_partition())
self.partitions.append(self.grub_boot)
# Offset all partitions by 1 sector.
# parted in jessie has changed and no longer allows
# partitions to be right next to each other.
partition_gap = Sectors(1, sector_size)
# The boot and swap partitions are optional
if 'boot' in data:
self.boot = GPTPartition(Sectors(data['boot']['size'], sector_size),
data['boot']['filesystem'], data['boot'].get('format_command', None),
data['boot'].get('mountopts', None), 'boot', last_partition())
if self.boot.previous is not None:
# No need to pad if this is the first partition
self.boot.pad_start += partition_gap
self.boot.size -= partition_gap
self.partitions.append(self.boot)
if 'swap' in data:
self.swap = GPTSwapPartition(Sectors(data['swap']['size'], sector_size), last_partition())
if self.swap.previous is not None:
self.swap.pad_start += partition_gap
self.swap.size -= partition_gap
self.partitions.append(self.swap)
self.root = GPTPartition(Sectors(data['root']['size'], sector_size),
data['root']['filesystem'], data['root'].get('format_command', None),
data['root'].get('mountopts', None), 'root', last_partition())
if self.root.previous is not None:
self.root.pad_start += partition_gap
self.root.size -= partition_gap
self.partitions.append(self.root)
# Create all additional partitions
for partition in data:
if partition not in ["boot", "swap", "root", "type"] and not None:
part_tmp = GPTPartition(Sectors(data[partition]['size'], sector_size),
data[partition]['filesystem'], data[partition].get('format_command', None),
data[partition].get('mountopts', None), partition, last_partition())
part_tmp.pad_start += partition_gap
part_tmp.size -= partition_gap
setattr(self, partition, part_tmp)
self.partitions.append(part_tmp)
if hasattr(self, 'grub_boot'):
# Mark the grub partition as a bios_grub partition
self.grub_boot.flags.append('bios_grub')
# Subtract the grub partition size from the subsequent partition
self.partitions[1].size -= self.grub_boot.size
else:
# Not using grub, mark the boot partition or root as bootable
getattr(self, 'boot', self.root).flags.append('legacy_boot')
# The first and last 34 sectors are reserved for the primary/secondary GPT
primary_gpt_size = Sectors(34, sector_size)
self.partitions[0].pad_start += primary_gpt_size
self.partitions[0].size -= primary_gpt_size
secondary_gpt_size = Sectors(34, sector_size)
self.partitions[-1].pad_end += secondary_gpt_size
self.partitions[-1].size -= secondary_gpt_size
super(GPTPartitionMap, self).__init__(bootloader)
def _before_create(self, event):
"""Creates the partition map
"""
volume = event.volume
# Disk alignment still plays a role in virtualized environment,
# but I honestly have no clue as to what best practice is here, so we choose 'none'
log_check_call(['parted', '--script', '--align', 'none', volume.device_path,
'--', 'mklabel', 'gpt'])
# Create the partitions
for partition in self.partitions:
partition.create(volume)