qubes-installer-qubes-os/anaconda/pyanaconda/storage/deviceaction.py
2013-01-24 01:45:53 +01:00

616 lines
21 KiB
Python

# deviceaction.py
# Device modification action classes for anaconda's storage configuration
# module.
#
# Copyright (C) 2009 Red Hat, Inc.
#
# This copyrighted material is made available to anyone wishing to use,
# modify, copy, or redistribute it subject to the terms and conditions of
# the GNU General Public License v.2, or (at your option) any later version.
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY expressed or implied, including the implied warranties of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details. You should have received a copy of the
# GNU General Public License along with this program; if not, write to the
# Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA. Any Red Hat trademarks that are incorporated in the
# source code or documentation are not subject to the GNU General Public
# License and may only be used or replicated with the express permission of
# Red Hat, Inc.
#
# Red Hat Author(s): Dave Lehman <dlehman@redhat.com>
#
from udev import *
import math
from devices import StorageDevice
from devices import PartitionDevice
from devices import LVMLogicalVolumeDevice
from formats import getFormat
from errors import *
from parted import partitionFlag, PARTITION_LBA
import gettext
_ = lambda x: gettext.ldgettext("anaconda", x)
import logging
log = logging.getLogger("storage")
# The values are just hints as to the ordering.
# Eg: fsmod and devmod ordering depends on the mod (shrink -v- grow)
ACTION_TYPE_NONE = 0
ACTION_TYPE_DESTROY = 1000
ACTION_TYPE_RESIZE = 500
ACTION_TYPE_MIGRATE = 250
ACTION_TYPE_CREATE = 100
action_strings = {ACTION_TYPE_NONE: "None",
ACTION_TYPE_DESTROY: "Destroy",
ACTION_TYPE_RESIZE: "Resize",
ACTION_TYPE_MIGRATE: "Migrate",
ACTION_TYPE_CREATE: "Create"}
ACTION_OBJECT_NONE = 0
ACTION_OBJECT_FORMAT = 1
ACTION_OBJECT_DEVICE = 2
object_strings = {ACTION_OBJECT_NONE: "None",
ACTION_OBJECT_FORMAT: "Format",
ACTION_OBJECT_DEVICE: "Device"}
RESIZE_SHRINK = 88
RESIZE_GROW = 89
resize_strings = {RESIZE_SHRINK: "Shrink",
RESIZE_GROW: "Grow"}
def action_type_from_string(type_string):
if type_string is None:
return None
for (k,v) in action_strings.items():
if v.lower() == type_string.lower():
return k
return resize_type_from_string(type_string)
def action_object_from_string(type_string):
if type_string is None:
return None
for (k,v) in object_strings.items():
if v.lower() == type_string.lower():
return k
def resize_type_from_string(type_string):
if type_string is None:
return None
for (k,v) in resize_strings.items():
if v.lower() == type_string.lower():
return k
class DeviceAction(object):
""" An action that will be carried out in the future on a Device.
These classes represent actions to be performed on devices or
filesystems.
The operand Device instance will be modified according to the
action, but no changes will be made to the underlying device or
filesystem until the DeviceAction instance's execute method is
called. The DeviceAction instance's cancel method should reverse
any modifications made to the Device instance's attributes.
If the Device instance represents a pre-existing device, the
constructor should call any methods or set any attributes that the
action will eventually change. Device/DeviceFormat classes should verify
that the requested modifications are reasonable and raise an
exception if not.
Only one action of any given type/object pair can exist for any
given device at any given time. This is enforced by the
DeviceTree.
Basic usage:
a = DeviceAction(dev)
a.execute()
OR
a = DeviceAction(dev)
a.cancel()
XXX should we back up the device with a deep copy for forcibly
cancelling actions?
The downside is that we lose any checking or verification that
would get done when resetting the Device instance's attributes to
their original values.
The upside is that we would be guaranteed to achieve a total
reversal. No chance of, eg: resizes ending up altering Device
size due to rounding or other miscalculation.
"""
type = ACTION_TYPE_NONE
obj = ACTION_OBJECT_NONE
_id = 0
def __init__(self, device):
if not isinstance(device, StorageDevice):
raise ValueError("arg 1 must be a StorageDevice instance")
self.device = device
# Establish a unique id for each action instance. Making shallow or
# deep copyies of DeviceAction instances will require __copy__ and
# __deepcopy__ methods to handle incrementing the id in the copy
self.id = DeviceAction._id
DeviceAction._id += 1
def execute(self):
""" perform the action """
pass
def cancel(self):
""" cancel the action """
pass
@property
def isDestroy(self):
return self.type == ACTION_TYPE_DESTROY
@property
def isCreate(self):
return self.type == ACTION_TYPE_CREATE
@property
def isMigrate(self):
return self.type == ACTION_TYPE_MIGRATE
@property
def isResize(self):
return self.type == ACTION_TYPE_RESIZE
@property
def isShrink(self):
return (self.type == ACTION_TYPE_RESIZE and self.dir == RESIZE_SHRINK)
@property
def isGrow(self):
return (self.type == ACTION_TYPE_RESIZE and self.dir == RESIZE_GROW)
@property
def isDevice(self):
return self.obj == ACTION_OBJECT_DEVICE
@property
def isFormat(self):
return self.obj == ACTION_OBJECT_FORMAT
@property
def format(self):
return self.device.format
def __str__(self):
s = "[%d] %s %s" % (self.id, action_strings[self.type],
object_strings[self.obj])
if self.isResize:
s += " (%s)" % resize_strings[self.dir]
if self.isFormat:
s += " %s" % self.format.desc
if self.isMigrate:
s += " to %s" % self.format.migrationTarget
s += " on"
s += " %s %s (id %d)" % (self.device.type, self.device.name,
self.device.id)
return s
def requires(self, action):
""" Return True if self requires action. """
return False
def obsoletes(self, action):
""" Return True is self obsoletes action.
DeviceAction instances obsolete other DeviceAction instances with
lower id and same device.
"""
return (self.device.id == action.device.id and
self.type == action.type and
self.obj == action.obj and
self.id > action.id)
class ActionCreateDevice(DeviceAction):
""" Action representing the creation of a new device. """
type = ACTION_TYPE_CREATE
obj = ACTION_OBJECT_DEVICE
def __init__(self, device):
if device.exists:
raise ValueError("device already exists")
# FIXME: assert device.fs is None
DeviceAction.__init__(self, device)
def execute(self):
self.device.create()
def requires(self, action):
""" Return True if self requires action.
Device create actions require other actions when either of the
following is true:
- this action's device depends on the other action's device
- both actions are partition create actions on the same disk
and this partition has a higher number
"""
rc = False
if self.device.dependsOn(action.device):
rc = True
elif (action.isCreate and action.isDevice and
isinstance(self.device, PartitionDevice) and
isinstance(action.device, PartitionDevice) and
self.device.disk == action.device.disk):
# create partitions in ascending numerical order
selfNum = self.device.partedPartition.number
otherNum = action.device.partedPartition.number
if selfNum > otherNum:
rc = True
elif (action.isCreate and action.isDevice and
isinstance(self.device, LVMLogicalVolumeDevice) and
isinstance(action.device, LVMLogicalVolumeDevice) and
self.device.vg == action.device.vg and
action.device.singlePV and not self.device.singlePV):
rc = True
return rc
class ActionDestroyDevice(DeviceAction):
""" An action representing the deletion of an existing device. """
type = ACTION_TYPE_DESTROY
obj = ACTION_OBJECT_DEVICE
def __init__(self, device):
# XXX should we insist that device.fs be None?
DeviceAction.__init__(self, device)
if device.exists:
device.teardown()
def execute(self):
self.device.destroy()
# Make sure libparted does not keep cached info for this device
# and returns it when we create a new device with the same name
if self.device.partedDevice:
try:
self.device.partedDevice.removeFromCache()
except Exception:
pass
def requires(self, action):
""" Return True if self requires action.
Device destroy actions require other actions when either of the
following is true:
- the other action's device depends on this action's device
- both actions are partition create actions on the same disk
and this partition has a lower number
"""
rc = False
if action.device.dependsOn(self.device) and action.isDestroy:
rc = True
elif (action.isDestroy and action.isDevice and
isinstance(self.device, PartitionDevice) and
isinstance(action.device, PartitionDevice) and
self.device.disk == action.device.disk):
# remove partitions in descending numerical order
selfNum = self.device.partedPartition.number
otherNum = action.device.partedPartition.number
if selfNum < otherNum:
rc = True
elif (action.isDestroy and action.isFormat and
action.device.id == self.device.id):
# device destruction comes after destruction of device's format
rc = True
return rc
def obsoletes(self, action):
""" Return True if self obsoletes action.
- obsoletes all actions w/ lower id that act on the same device,
including self, if device does not exist
- obsoletes all but ActionDestroyFormat actions w/ lower id on the
same device if device exists
"""
rc = False
if action.device.id == self.device.id:
if self.id >= action.id and not self.device.exists:
rc = True
elif self.id > action.id and \
self.device.exists and \
not (action.isDestroy and action.isFormat):
rc = True
return rc
class ActionResizeDevice(DeviceAction):
""" An action representing the resizing of an existing device. """
type = ACTION_TYPE_RESIZE
obj = ACTION_OBJECT_DEVICE
def __init__(self, device, newsize):
if not device.resizable:
raise ValueError("device is not resizable")
if long(math.floor(device.currentSize)) == newsize:
raise ValueError("new size same as old size")
DeviceAction.__init__(self, device)
if newsize > long(math.floor(device.currentSize)):
self.dir = RESIZE_GROW
else:
self.dir = RESIZE_SHRINK
if device.targetSize > 0:
self.origsize = device.targetSize
else:
self.origsize = device.size
self.device.targetSize = newsize
def execute(self):
self.device.resize()
def cancel(self):
self.device.targetSize = self.origsize
def requires(self, action):
""" Return True if self requires action.
A device resize action requires another action if:
- the other action is a format resize on the same device and
both are shrink operations
- the other action grows a device (or format it contains) that
this action's device depends on
- the other action shrinks a device (or format it contains)
that depends on this action's device
"""
retval = False
if action.isResize:
if self.device.id == action.device.id and \
self.dir == action.dir and \
action.isFormat and self.isShrink:
retval = True
elif action.isGrow and self.device.dependsOn(action.device):
retval = True
elif action.isShrink and action.device.dependsOn(self.device):
retval = True
return retval
class ActionCreateFormat(DeviceAction):
""" An action representing creation of a new filesystem. """
type = ACTION_TYPE_CREATE
obj = ACTION_OBJECT_FORMAT
def __init__(self, device, format=None):
DeviceAction.__init__(self, device)
if format:
self.origFormat = device.format
if self.device.format.exists:
self.device.format.teardown()
self.device.format = format
else:
self.origFormat = getFormat(None)
def execute(self):
from pyanaconda.progress import progress_report
msg = _("Creating %(type)s on %(device)s") % {"type": self.device.format.type, "device": self.device.path}
with progress_report(msg):
self.device.setup()
if isinstance(self.device, PartitionDevice):
for flag in partitionFlag.keys():
# Keep the LBA flag on pre-existing partitions
if flag in [ PARTITION_LBA, self.format.partedFlag ]:
continue
self.device.unsetFlag(flag)
if self.format.partedFlag is not None:
self.device.setFlag(self.format.partedFlag)
if self.format.partedSystem is not None:
self.device.partedPartition.system = self.format.partedSystem
self.device.disk.format.commitToDisk()
self.device.format.create(device=self.device.path,
options=self.device.formatArgs)
# Get the UUID now that the format is created
udev_settle()
self.device.updateSysfsPath()
info = udev_get_block_device(self.device.sysfsPath)
self.device.format.uuid = udev_device_get_uuid(info)
def cancel(self):
self.device.format = self.origFormat
def requires(self, action):
""" Return True if self requires action.
Format create action can require another action if:
- this action's device depends on the other action's device
and the other action is not a device destroy action
- the other action is a create or resize of this action's
device
"""
return ((self.device.dependsOn(action.device) and
not (action.isDestroy and action.isDevice)) or
(action.isDevice and (action.isCreate or action.isResize) and
self.device.id == action.device.id))
def obsoletes(self, action):
""" Return True if this action obsoletes action.
Format create actions obsolete the following actions:
- format actions w/ lower id on this action's device, other
than those that destroy existing formats
"""
return (self.device.id == action.device.id and
self.obj == action.obj and
not (action.isDestroy and action.format.exists) and
self.id > action.id)
class ActionDestroyFormat(DeviceAction):
""" An action representing the removal of an existing filesystem. """
type = ACTION_TYPE_DESTROY
obj = ACTION_OBJECT_FORMAT
def __init__(self, device):
DeviceAction.__init__(self, device)
self.origFormat = self.device.format
if device.format.exists:
device.format.teardown()
self.device.format = None
def execute(self):
""" wipe the filesystem signature from the device """
self.device.setup(orig=True)
self.format.destroy()
udev_settle()
self.device.teardown()
def cancel(self):
self.device.format = self.origFormat
@property
def format(self):
return self.origFormat
def requires(self, action):
""" Return True if self requires action.
Format destroy actions require other actions when:
- the other action's device depends on this action's device
and the other action is a destroy action
"""
return action.device.dependsOn(self.device) and action.isDestroy
def obsoletes(self, action):
""" Return True if this action obsoletes action.
Format destroy actions obsolete the following actions:
- format actions w/ lower id on same device, including self if
format does not exist
- format destroy action on a non-existent format shouldn't
obsolete a format destroy action on an existing one
"""
return (self.device.id == action.device.id and
self.obj == action.obj and
(self.id > action.id or
(self.id == action.id and not self.format.exists)) and
not (action.format.exists and not self.format.exists))
class ActionResizeFormat(DeviceAction):
""" An action representing the resizing of an existing filesystem.
XXX Do we even want to support resizing of a filesystem without
also resizing the device it resides on?
"""
type = ACTION_TYPE_RESIZE
obj = ACTION_OBJECT_FORMAT
def __init__(self, device, newsize):
if not device.format.resizable:
raise ValueError("format is not resizable")
if long(math.floor(device.format.currentSize)) == newsize:
raise ValueError("new size same as old size")
DeviceAction.__init__(self, device)
if newsize > long(math.floor(device.format.currentSize)):
self.dir = RESIZE_GROW
else:
self.dir = RESIZE_SHRINK
self.origSize = self.device.format.targetSize
self.device.format.targetSize = newsize
def execute(self):
from pyanaconda.progress import progress_report
msg = _("Resizing filesystem on %(device)s") % {"device": self.device.path}
with progress_report(msg):
self.device.setup(orig=True)
self.device.format.doResize()
def cancel(self):
self.device.format.targetSize = self.origSize
def requires(self, action):
""" Return True if self requires action.
A format resize action requires another action if:
- the other action is a device resize on the same device and
both are grow operations
- the other action shrinks a device (or format it contains)
that depends on this action's device
- the other action grows a device (or format) that this
action's device depends on
"""
retval = False
if action.isResize:
if self.device.id == action.device.id and \
self.dir == action.dir and \
action.isDevice and self.isGrow:
retval = True
elif action.isShrink and action.device.dependsOn(self.device):
retval = True
elif action.isGrow and self.device.dependsOn(action.device):
retval = True
return retval
class ActionMigrateFormat(DeviceAction):
""" An action representing the migration of an existing filesystem. """
type = ACTION_TYPE_MIGRATE
obj = ACTION_OBJECT_FORMAT
def __init__(self, device):
if not device.format.migratable or not device.format.exists:
raise ValueError("device format is not migratable")
DeviceAction.__init__(self, device)
self.device.format.migrate = True
def execute(self):
from pyanaconda.progress import progress_report
msg = _("Migrating filesystem on %(device)s") % {"device": self.device.path}
with progress_report(msg):
self.device.setup(orig=True)
self.device.format.doMigrate()
def cancel(self):
self.device.format.migrate = False