_wait_and_reraise() is similar to asyncio.gather(), but it preserves the current behavior of waiting for all futures and only _then_ reraising the first exception (if there is any) in line. Also switch Storage.create() and Storage.clone() to _wait_and_reraise(). Previously, they called asyncio.wait() and implicitly swallowed all exceptions.
		
			
				
	
	
		
			958 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			958 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
#
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# The Qubes OS Project, https://www.qubes-os.org/
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#
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# Copyright (C) 2013-2015  Joanna Rutkowska <joanna@invisiblethingslab.com>
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# Copyright (C) 2013-2015  Marek Marczykowski-Górecki
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#                              <marmarek@invisiblethingslab.com>
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# Copyright (C) 2015  Wojtek Porczyk <woju@invisiblethingslab.com>
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#
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# This library is free software; you can redistribute it and/or
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# modify it under the terms of the GNU Lesser General Public
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# License as published by the Free Software Foundation; either
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# version 2.1 of the License, or (at your option) any later version.
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#
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# This library is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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# Lesser General Public License for more details.
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#
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# You should have received a copy of the GNU Lesser General Public
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# License along with this library; if not, see <https://www.gnu.org/licenses/>.
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#
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""" Qubes storage system"""
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from __future__ import absolute_import
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import inspect
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import os
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import os.path
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import string  # pylint: disable=deprecated-module
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import subprocess
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import time
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from datetime import datetime
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import asyncio
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import lxml.etree
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import pkg_resources
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import qubes
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import qubes.exc
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import qubes.utils
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STORAGE_ENTRY_POINT = 'qubes.storage'
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class StoragePoolException(qubes.exc.QubesException):
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    ''' A general storage exception '''
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    pass
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class BlockDevice:
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    ''' Represents a storage block device. '''
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    # pylint: disable=too-few-public-methods
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    def __init__(self, path, name, script=None, rw=True, domain=None,
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                 devtype='disk'):
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        assert name, 'Missing device name'
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        assert path, 'Missing device path'
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        self.path = path
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        self.name = name
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        self.rw = rw
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        self.script = script
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        self.domain = domain
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        self.devtype = devtype
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class Volume:
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    ''' Encapsulates all data about a volume for serialization to qubes.xml and
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        libvirt config.
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        Keep in mind!
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        volatile        = not snap_on_start and not save_on_stop
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        snapshot        =     snap_on_start and not save_on_stop
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        origin          = not snap_on_start and     save_on_stop
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        origin_snapshot =     snap_on_start and     save_on_stop
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    '''
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    devtype = 'disk'
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    domain = None
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    path = None
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    script = None
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    #: disk space used by this volume, can be smaller than :py:attr:`size`
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    #: for sparse volumes
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    usage = 0
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    def __init__(self, name, pool, vid,
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            revisions_to_keep=0, rw=False, save_on_stop=False, size=0,
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            snap_on_start=False, source=None, **kwargs):
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        ''' Initialize a volume.
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            :param str name: The name of the volume inside owning domain
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            :param Pool pool: The pool object
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            :param str vid:  Volume identifier needs to be unique in pool
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            :param int revisions_to_keep: Amount of revisions to keep around
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            :param bool rw: If true volume will be mounted read-write
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            :param bool snap_on_start: Create a snapshot from source on
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                start, instead of using volume own data
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            :param bool save_on_stop: Write changes to the volume in
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                vm.stop(), otherwise - discard
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            :param Volume source: other volume in same pool to make snapshot
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                from, required if *snap_on_start*=`True`
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            :param str/int size: Size of the volume
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        '''
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        super(Volume, self).__init__(**kwargs)
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        assert isinstance(pool, Pool)
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        assert source is None or (isinstance(source, Volume)
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                                  and source.pool == pool)
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        if snap_on_start and source is None:
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            msg = "snap_on_start specified on {!r} but no volume source set"
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            msg = msg.format(name)
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            raise StoragePoolException(msg)
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        elif not snap_on_start and source is not None:
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            msg = "source specified on {!r} but no snap_on_start set"
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            msg = msg.format(name)
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            raise StoragePoolException(msg)
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        #: Name of the volume in a domain it's attached to (like `root` or
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        #: `private`).
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        self.name = str(name)
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        #: :py:class:`Pool` instance owning this volume
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        self.pool = pool
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        #: How many revisions of the volume to keep. Each revision is created
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        #  at :py:meth:`stop`, if :py:attr:`save_on_stop` is True
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        self.revisions_to_keep = int(revisions_to_keep)
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        #: Should this volume be writable by domain.
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        self.rw = rw
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        #: Should volume state be saved or discarded at :py:meth:`stop`
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        self.save_on_stop = save_on_stop
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        self._size = int(size)
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        #: Should the volume state be initialized with a snapshot of
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        #: same-named volume of domain's template.
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        self.snap_on_start = snap_on_start
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        #: source volume for :py:attr:`snap_on_start` volumes
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        self.source = source
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        #: Volume unique (inside given pool) identifier
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        self.vid = vid
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    def __eq__(self, other):
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        if isinstance(other, Volume):
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            return other.pool == self.pool and other.vid == self.vid
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        return NotImplemented
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    def __hash__(self):
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        return hash('%s:%s' % (self.pool, self.vid))
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    def __neq__(self, other):
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        return not self.__eq__(other)
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    def __repr__(self):
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        return '{!r}'.format(str(self.pool) + ':' + self.vid)
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    def __str__(self):
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        return str(self.vid)
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    def __xml__(self):
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        config = _sanitize_config(self.config)
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        return lxml.etree.Element('volume', **config)
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    def create(self):
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        ''' Create the given volume on disk.
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            This method is called only once in the volume lifetime. Before
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            calling this method, no data on disk should be touched (in
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            context of this volume).
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            This can be implemented as a coroutine.
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        '''
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        raise self._not_implemented("create")
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    def remove(self):
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        ''' Remove volume.
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        This can be implemented as a coroutine.'''
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        raise self._not_implemented("remove")
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    def export(self):
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        ''' Returns a path to read the volume data from.
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            Reading from this path when domain owning this volume is
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            running (i.e. when :py:meth:`is_dirty` is True) should return the
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            data from before domain startup.
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            Reading from the path returned by this method should return the
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            volume data. If extracting volume data require something more
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            than just reading from file (for example connecting to some other
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            domain, or decompressing the data), the returned path may be a pipe.
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        '''
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        raise self._not_implemented("export")
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    def import_data(self):
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        ''' Returns a path to overwrite volume data.
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            This method is called after volume was already :py:meth:`create`-ed.
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            Writing to this path should overwrite volume data. If importing
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            volume data require something more than just writing to a file (
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            for example connecting to some other domain, or converting data
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            on the fly), the returned path may be a pipe.
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        '''
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        raise self._not_implemented("import")
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    def import_data_end(self, success):
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        ''' End the data import operation. This may be used by pool
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        implementation to commit changes, cleanup temporary files etc.
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        This method is called regardless the operation was successful or not.
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        :param success: True if data import was successful, otherwise False
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        '''
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        # by default do nothing
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        pass
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    def import_volume(self, src_volume):
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        ''' Imports data from a different volume (possibly in a different
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        pool.
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        The volume needs to be create()d first.
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        This can be implemented as a coroutine. '''
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        # pylint: disable=unused-argument
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        raise self._not_implemented("import_volume")
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    def is_dirty(self):
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        ''' Return `True` if volume was not properly shutdown and committed.
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            This include the situation when domain owning the volume is still
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            running.
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        '''
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        raise self._not_implemented("is_dirty")
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    def is_outdated(self):
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        ''' Returns `True` if this snapshot of a source volume (for
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        `snap_on_start`=True) is outdated.
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        '''
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        raise self._not_implemented("is_outdated")
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    def resize(self, size):
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        ''' Expands volume, throws
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            :py:class:`qubes.storage.StoragePoolException` if
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            given size is less than current_size
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            This can be implemented as a coroutine.
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            :param int size: new size in bytes
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        '''
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        # pylint: disable=unused-argument
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        raise self._not_implemented("resize")
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    def revert(self, revision=None):
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        ''' Revert volume to previous revision
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        This can be implemented as a coroutine.
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        :param revision: revision to revert volume to, see :py:attr:`revisions`
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        '''
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        # pylint: disable=unused-argument
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        raise self._not_implemented("revert")
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    def start(self):
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        ''' Do what ever is needed on start.
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        This include making a snapshot of template's volume if
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        :py:attr:`snap_on_start` is set.
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        This can be implemented as a coroutine.'''
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        raise self._not_implemented("start")
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    def stop(self):
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        ''' Do what ever is needed on stop.
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        This include committing data if :py:attr:`save_on_stop` is set.
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        This can be implemented as a coroutine.'''
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        raise self._not_implemented("stop")
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    def verify(self):
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        ''' Verifies the volume.
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        This function is supposed to either return :py:obj:`True`, or raise
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        an exception.
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        This can be implemented as a coroutine.'''
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        raise self._not_implemented("verify")
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    def block_device(self):
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        ''' Return :py:class:`BlockDevice` for serialization in
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            the libvirt XML template as <disk>.
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        '''
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        return BlockDevice(self.path, self.name, self.script,
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                                         self.rw, self.domain, self.devtype)
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    @property
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    def revisions(self):
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        ''' Returns a dict containing revision identifiers and time of their
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        creation '''
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        msg = "{!s} has revisions not implemented".format(self.__class__)
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        raise NotImplementedError(msg)
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    @property
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    def size(self):
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        ''' Volume size in bytes '''
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        return self._size
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    @size.setter
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    def size(self, size):
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        # pylint: disable=attribute-defined-outside-init
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        self._size = int(size)
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    @property
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    def config(self):
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        ''' return config data for serialization to qubes.xml '''
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        result = {
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            'name': self.name,
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            'pool': str(self.pool),
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            'vid': self.vid,
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            'revisions_to_keep': self.revisions_to_keep,
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            'rw': self.rw,
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            'save_on_stop': self.save_on_stop,
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            'snap_on_start': self.snap_on_start,
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        }
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        if self.size:
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            result['size'] = self.size
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        if self.source:
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            result['source'] = str(self.source)
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        return result
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    def _not_implemented(self, method_name):
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        ''' Helper for emitting helpful `NotImplementedError` exceptions '''
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        msg = "Volume {!s} has {!s}() not implemented"
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        msg = msg.format(str(self.__class__.__name__), method_name)
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        return NotImplementedError(msg)
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class Storage:
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    ''' Class for handling VM virtual disks.
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    This is base class for all other implementations, mostly with Xen on Linux
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    in mind.
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    '''
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    AVAILABLE_FRONTENDS = {'xvd' + c for c in string.ascii_lowercase}
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    def __init__(self, vm):
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        #: Domain for which we manage storage
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        self.vm = vm
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        self.log = self.vm.log
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        #: Additional drive (currently used only by HVM)
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        self.drive = None
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        if hasattr(vm, 'volume_config'):
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            for name, conf in self.vm.volume_config.items():
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                self.init_volume(name, conf)
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    def _update_volume_config_source(self, name, volume_config):
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        '''Retrieve 'source' volume from VM's template'''
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        template = getattr(self.vm, 'template', None)
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        # recursively lookup source volume - templates may be
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        # chained (TemplateVM -> AppVM -> DispVM, where the
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        # actual source should be used from TemplateVM)
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        while template:
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            source = template.volumes[name]
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            volume_config['source'] = source
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            volume_config['pool'] = source.pool
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            volume_config['size'] = source.size
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            if source.source is not None:
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                template = getattr(template, 'template', None)
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            else:
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                break
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    def init_volume(self, name, volume_config):
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        ''' Initialize Volume instance attached to this domain '''
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        if 'name' not in volume_config:
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            volume_config['name'] = name
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        if 'source' in volume_config:
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            # we have no control over VM load order,
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            # so initialize storage recursively if needed
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            template = getattr(self.vm, 'template', None)
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            if template and template.storage is None:
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                template.storage = Storage(template)
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            if volume_config['source'] is None:
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                self._update_volume_config_source(name, volume_config)
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            else:
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                # if source is already specified, pool needs to be too
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                pool = self.vm.app.get_pool(volume_config['pool'])
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                volume_config['source'] = pool.volumes[volume_config['source']]
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 | 
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        # if pool still unknown, load default
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        if 'pool' not in volume_config:
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            volume_config['pool'] = \
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                getattr(self.vm.app, 'default_pool_' + name)
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        pool = self.vm.app.get_pool(volume_config['pool'])
 | 
						|
        if 'internal' in volume_config:
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            # migrate old config
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            del volume_config['internal']
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        volume = pool.init_volume(self.vm, volume_config)
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        self.vm.volumes[name] = volume
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        return volume
 | 
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    def attach(self, volume, rw=False):
 | 
						|
        ''' Attach a volume to the domain '''
 | 
						|
        assert self.vm.is_running()
 | 
						|
 | 
						|
        if self._is_already_attached(volume):
 | 
						|
            self.vm.log.info("{!r} already attached".format(volume))
 | 
						|
            return
 | 
						|
 | 
						|
        try:
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						|
            frontend = self.unused_frontend()
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						|
        except IndexError:
 | 
						|
            raise StoragePoolException("No unused frontend found")
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        disk = lxml.etree.Element("disk")
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						|
        disk.set('type', 'block')
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						|
        disk.set('device', 'disk')
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						|
        lxml.etree.SubElement(disk, 'driver').set('name', 'phy')
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						|
        lxml.etree.SubElement(disk, 'source').set('dev', '/dev/%s' % volume.vid)
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        lxml.etree.SubElement(disk, 'target').set('dev', frontend)
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        if not rw:
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						|
            lxml.etree.SubElement(disk, 'readonly')
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						|
 | 
						|
        if volume.domain is not None:
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            lxml.etree.SubElement(disk, 'backenddomain').set(
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                'name', volume.domain.name)
 | 
						|
 | 
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        xml_string = lxml.etree.tostring(disk, encoding='utf-8')
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						|
        self.vm.libvirt_domain.attachDevice(xml_string)
 | 
						|
        # trigger watches to update device status
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						|
        # FIXME: this should be removed once libvirt will report such
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						|
        # events itself
 | 
						|
        # self.vm.untrusted_qdb.write('/qubes-block-devices', '')
 | 
						|
        # ← do we need this?
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						|
 | 
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    def _is_already_attached(self, volume):
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						|
        ''' Checks if the given volume is already attached '''
 | 
						|
        parsed_xml = lxml.etree.fromstring(self.vm.libvirt_domain.XMLDesc())
 | 
						|
        disk_sources = parsed_xml.xpath("//domain/devices/disk/source")
 | 
						|
        for source in disk_sources:
 | 
						|
            if source.get('dev') == '/dev/%s' % volume.vid:
 | 
						|
                return True
 | 
						|
        return False
 | 
						|
 | 
						|
    def detach(self, volume):
 | 
						|
        ''' Detach a volume from domain '''
 | 
						|
        parsed_xml = lxml.etree.fromstring(self.vm.libvirt_domain.XMLDesc())
 | 
						|
        disks = parsed_xml.xpath("//domain/devices/disk")
 | 
						|
        for disk in disks:
 | 
						|
            source = disk.xpath('source')[0]
 | 
						|
            if source.get('dev') == '/dev/%s' % volume.vid:
 | 
						|
                disk_xml = lxml.etree.tostring(disk, encoding='utf-8')
 | 
						|
                self.vm.libvirt_domain.detachDevice(disk_xml)
 | 
						|
                return
 | 
						|
        raise StoragePoolException('Volume {!r} is not attached'.format(volume))
 | 
						|
 | 
						|
    @property
 | 
						|
    def kernels_dir(self):
 | 
						|
        '''Directory where kernel resides.
 | 
						|
 | 
						|
        If :py:attr:`self.vm.kernel` is :py:obj:`None`, the this points inside
 | 
						|
        :py:attr:`self.vm.dir_path`
 | 
						|
        '''
 | 
						|
        assert 'kernel' in self.vm.volumes, "VM has no kernel volume"
 | 
						|
        return self.vm.volumes['kernel'].kernels_dir
 | 
						|
 | 
						|
    def get_disk_utilization(self):
 | 
						|
        ''' Returns summed up disk utilization for all domain volumes '''
 | 
						|
        result = 0
 | 
						|
        for volume in self.vm.volumes.values():
 | 
						|
            result += volume.usage
 | 
						|
        return result
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def resize(self, volume, size):
 | 
						|
        ''' Resizes volume a read-writable volume '''
 | 
						|
        if isinstance(volume, str):
 | 
						|
            volume = self.vm.volumes[volume]
 | 
						|
        ret = volume.resize(size)
 | 
						|
        if asyncio.iscoroutine(ret):
 | 
						|
            yield from ret
 | 
						|
        if self.vm.is_running():
 | 
						|
            try:
 | 
						|
                yield from self.vm.run_service_for_stdio('qubes.ResizeDisk',
 | 
						|
                    input=volume.name.encode(),
 | 
						|
                    user='root')
 | 
						|
            except subprocess.CalledProcessError as e:
 | 
						|
                service_error = e.stderr.decode('ascii', errors='ignore')
 | 
						|
                service_error = service_error.replace('%', '')
 | 
						|
                raise StoragePoolException(
 | 
						|
                    'Online resize of volume {} failed (you need to resize '
 | 
						|
                    'filesystem manually): {}'.format(volume, service_error))
 | 
						|
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def create(self):
 | 
						|
        ''' Creates volumes on disk '''
 | 
						|
        old_umask = os.umask(0o002)
 | 
						|
 | 
						|
        coros = []
 | 
						|
        for volume in self.vm.volumes.values():
 | 
						|
            # launch the operation, if it's asynchronous, then append to wait
 | 
						|
            #  for them at the end
 | 
						|
            ret = volume.create()
 | 
						|
            if asyncio.iscoroutine(ret):
 | 
						|
                coros.append(ret)
 | 
						|
        yield from _wait_and_reraise(coros)
 | 
						|
 | 
						|
        os.umask(old_umask)
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def clone_volume(self, src_vm, name):
 | 
						|
        ''' Clone single volume from the specified vm
 | 
						|
 | 
						|
        :param QubesVM src_vm: source VM
 | 
						|
        :param str name: name of volume to clone ('root', 'private' etc)
 | 
						|
        :return cloned volume object
 | 
						|
        '''
 | 
						|
        config = self.vm.volume_config[name]
 | 
						|
        dst_pool = self.vm.app.get_pool(config['pool'])
 | 
						|
        dst = dst_pool.init_volume(self.vm, config)
 | 
						|
        src_volume = src_vm.volumes[name]
 | 
						|
        msg = "Importing volume {!s} from vm {!s}"
 | 
						|
        self.vm.log.info(msg.format(src_volume.name, src_vm.name))
 | 
						|
 | 
						|
        # First create the destination volume
 | 
						|
        create_op_ret = dst.create()
 | 
						|
        # clone/import functions may be either synchronous or asynchronous
 | 
						|
        # in the later case, we need to wait for them to finish
 | 
						|
        if asyncio.iscoroutine(create_op_ret):
 | 
						|
            yield from create_op_ret
 | 
						|
 | 
						|
        # Then import data from source volume
 | 
						|
        clone_op_ret = dst.import_volume(src_volume)
 | 
						|
 | 
						|
        # clone/import functions may be either synchronous or asynchronous
 | 
						|
        # in the later case, we need to wait for them to finish
 | 
						|
        if asyncio.iscoroutine(clone_op_ret):
 | 
						|
            yield from clone_op_ret
 | 
						|
        self.vm.volumes[name] = dst
 | 
						|
        return self.vm.volumes[name]
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def clone(self, src_vm):
 | 
						|
        ''' Clone volumes from the specified vm '''
 | 
						|
 | 
						|
        self.vm.volumes = {}
 | 
						|
        with VmCreationManager(self.vm):
 | 
						|
            yield from _wait_and_reraise([self.clone_volume(src_vm, vol_name)
 | 
						|
                for vol_name in self.vm.volume_config.keys()])
 | 
						|
 | 
						|
    @property
 | 
						|
    def outdated_volumes(self):
 | 
						|
        ''' Returns a list of outdated volumes '''
 | 
						|
        result = []
 | 
						|
        if self.vm.is_halted():
 | 
						|
            return result
 | 
						|
 | 
						|
        volumes = self.vm.volumes
 | 
						|
        for volume in volumes.values():
 | 
						|
            if volume.is_outdated():
 | 
						|
                result += [volume]
 | 
						|
 | 
						|
        return result
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def verify(self):
 | 
						|
        '''Verify that the storage is sane.
 | 
						|
 | 
						|
        On success, returns normally. On failure, raises exception.
 | 
						|
        '''
 | 
						|
        if not os.path.exists(self.vm.dir_path):
 | 
						|
            raise qubes.exc.QubesVMError(
 | 
						|
                self.vm,
 | 
						|
                'VM directory does not exist: {}'.format(self.vm.dir_path))
 | 
						|
        futures = []
 | 
						|
        for volume in self.vm.volumes.values():
 | 
						|
            ret = volume.verify()
 | 
						|
            if asyncio.iscoroutine(ret):
 | 
						|
                futures.append(ret)
 | 
						|
        yield from _wait_and_reraise(futures)
 | 
						|
        self.vm.fire_event('domain-verify-files')
 | 
						|
        return True
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def remove(self):
 | 
						|
        ''' Remove all the volumes.
 | 
						|
 | 
						|
            Errors on removal are catched and logged.
 | 
						|
        '''
 | 
						|
        futures = []
 | 
						|
        for name, volume in self.vm.volumes.items():
 | 
						|
            self.log.info('Removing volume %s: %s' % (name, volume.vid))
 | 
						|
            try:
 | 
						|
                ret = volume.remove()
 | 
						|
                if asyncio.iscoroutine(ret):
 | 
						|
                    futures.append(ret)
 | 
						|
            except (IOError, OSError) as e:
 | 
						|
                self.vm.log.exception("Failed to remove volume %s", name, e)
 | 
						|
 | 
						|
        try:
 | 
						|
            yield from _wait_and_reraise(futures)
 | 
						|
        except (IOError, OSError) as e:
 | 
						|
            self.vm.log.exception("Failed to remove some volume", e)
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def start(self):
 | 
						|
        ''' Execute the start method on each volume '''
 | 
						|
        futures = []
 | 
						|
        for volume in self.vm.volumes.values():
 | 
						|
            ret = volume.start()
 | 
						|
            if asyncio.iscoroutine(ret):
 | 
						|
                futures.append(ret)
 | 
						|
 | 
						|
        yield from _wait_and_reraise(futures)
 | 
						|
 | 
						|
    @asyncio.coroutine
 | 
						|
    def stop(self):
 | 
						|
        ''' Execute the stop method on each volume '''
 | 
						|
        futures = []
 | 
						|
        for volume in self.vm.volumes.values():
 | 
						|
            ret = volume.stop()
 | 
						|
            if asyncio.iscoroutine(ret):
 | 
						|
                futures.append(ret)
 | 
						|
 | 
						|
        yield from _wait_and_reraise(futures)
 | 
						|
 | 
						|
    def unused_frontend(self):
 | 
						|
        ''' Find an unused device name '''
 | 
						|
        unused_frontends = self.AVAILABLE_FRONTENDS.difference(
 | 
						|
            self.used_frontends)
 | 
						|
        return sorted(unused_frontends)[0]
 | 
						|
 | 
						|
    @property
 | 
						|
    def used_frontends(self):
 | 
						|
        ''' Used device names '''
 | 
						|
        xml = self.vm.libvirt_domain.XMLDesc()
 | 
						|
        parsed_xml = lxml.etree.fromstring(xml)
 | 
						|
        return {target.get('dev', None)
 | 
						|
                    for target in parsed_xml.xpath(
 | 
						|
                        "//domain/devices/disk/target")}
 | 
						|
 | 
						|
    def export(self, volume):
 | 
						|
        ''' Helper function to export volume (pool.export(volume))'''
 | 
						|
        assert isinstance(volume, (Volume, str)), \
 | 
						|
            "You need to pass a Volume or pool name as str"
 | 
						|
        if isinstance(volume, Volume):
 | 
						|
            return volume.export()
 | 
						|
 | 
						|
        return self.vm.volumes[volume].export()
 | 
						|
 | 
						|
    def import_data(self, volume):
 | 
						|
        ''' Helper function to import volume data (pool.import_data(volume))'''
 | 
						|
        assert isinstance(volume, (Volume, str)), \
 | 
						|
            "You need to pass a Volume or pool name as str"
 | 
						|
        if isinstance(volume, Volume):
 | 
						|
            return volume.import_data()
 | 
						|
 | 
						|
        return self.vm.volumes[volume].import_data()
 | 
						|
 | 
						|
    def import_data_end(self, volume, success):
 | 
						|
        ''' Helper function to finish/cleanup data import
 | 
						|
        (pool.import_data_end( volume))'''
 | 
						|
        assert isinstance(volume, (Volume, str)), \
 | 
						|
            "You need to pass a Volume or pool name as str"
 | 
						|
        if isinstance(volume, Volume):
 | 
						|
            return volume.import_data_end(success=success)
 | 
						|
 | 
						|
        return self.vm.volumes[volume].import_data_end(success=success)
 | 
						|
 | 
						|
 | 
						|
class VolumesCollection:
 | 
						|
    '''Convenient collection wrapper for pool.get_volume and
 | 
						|
    pool.list_volumes
 | 
						|
    '''
 | 
						|
    def __init__(self, pool):
 | 
						|
        self._pool = pool
 | 
						|
 | 
						|
    def __getitem__(self, item):
 | 
						|
        ''' Get a single volume with given Volume ID.
 | 
						|
 | 
						|
        You can also a Volume instance to get the same Volume or KeyError if
 | 
						|
        Volume no longer exists.
 | 
						|
 | 
						|
        :param item: a Volume ID (str) or a Volume instance
 | 
						|
        '''
 | 
						|
        if isinstance(item, Volume):
 | 
						|
            if item.pool == self._pool:
 | 
						|
                return self[item.vid]
 | 
						|
            raise KeyError(item)
 | 
						|
        try:
 | 
						|
            return self._pool.get_volume(item)
 | 
						|
        except NotImplementedError:
 | 
						|
            for vol in self:
 | 
						|
                if vol.vid == item:
 | 
						|
                    return vol
 | 
						|
            # if list_volumes is not implemented too, it will raise
 | 
						|
            # NotImplementedError again earlier
 | 
						|
            raise KeyError(item)
 | 
						|
 | 
						|
    def __iter__(self):
 | 
						|
        ''' Get iterator over pool's volumes '''
 | 
						|
        return iter(self._pool.list_volumes())
 | 
						|
 | 
						|
    def __contains__(self, item):
 | 
						|
        ''' Check if given volume (either Volume ID or Volume instance) is
 | 
						|
        present in the pool
 | 
						|
        '''
 | 
						|
        try:
 | 
						|
            return self[item] is not None
 | 
						|
        except KeyError:
 | 
						|
            return False
 | 
						|
 | 
						|
    def keys(self):
 | 
						|
        ''' Return list of volume IDs '''
 | 
						|
        return [vol.vid for vol in self]
 | 
						|
 | 
						|
    def values(self):
 | 
						|
        ''' Return list of Volumes'''
 | 
						|
        return [vol for vol in self]
 | 
						|
 | 
						|
 | 
						|
class Pool:
 | 
						|
    ''' A Pool is used to manage different kind of volumes (File
 | 
						|
        based/LVM/Btrfs/...).
 | 
						|
 | 
						|
        3rd Parties providing own storage implementations will need to extend
 | 
						|
        this class.
 | 
						|
    '''  # pylint: disable=unused-argument
 | 
						|
    private_img_size = qubes.config.defaults['private_img_size']
 | 
						|
    root_img_size = qubes.config.defaults['root_img_size']
 | 
						|
 | 
						|
    def __init__(self, name, revisions_to_keep=1, **kwargs):
 | 
						|
        super(Pool, self).__init__(**kwargs)
 | 
						|
        self._volumes_collection = VolumesCollection(self)
 | 
						|
        self.name = name
 | 
						|
        self.revisions_to_keep = revisions_to_keep
 | 
						|
        kwargs['name'] = self.name
 | 
						|
 | 
						|
    def __eq__(self, other):
 | 
						|
        if isinstance(other, Pool):
 | 
						|
            return self.name == other.name
 | 
						|
        if isinstance(other, str):
 | 
						|
            return self.name == other
 | 
						|
        return NotImplemented
 | 
						|
 | 
						|
    def __neq__(self, other):
 | 
						|
        return not self.__eq__(other)
 | 
						|
 | 
						|
    def __str__(self):
 | 
						|
        return self.name
 | 
						|
 | 
						|
    def __hash__(self):
 | 
						|
        return hash(self.name)
 | 
						|
 | 
						|
    def __xml__(self):
 | 
						|
        config = _sanitize_config(self.config)
 | 
						|
        return lxml.etree.Element('pool', **config)
 | 
						|
 | 
						|
    @property
 | 
						|
    def config(self):
 | 
						|
        ''' Returns the pool config to be written to qubes.xml '''
 | 
						|
        raise self._not_implemented("config")
 | 
						|
 | 
						|
    def destroy(self):
 | 
						|
        ''' Called when removing the pool. Use this for implementation specific
 | 
						|
            clean up.
 | 
						|
        '''
 | 
						|
        raise self._not_implemented("destroy")
 | 
						|
 | 
						|
    def init_volume(self, vm, volume_config):
 | 
						|
        ''' Initialize a :py:class:`qubes.storage.Volume` from `volume_config`.
 | 
						|
        '''
 | 
						|
        raise self._not_implemented("init_volume")
 | 
						|
 | 
						|
    def setup(self):
 | 
						|
        ''' Called when adding a pool to the system. Use this for implementation
 | 
						|
            specific set up.
 | 
						|
        '''
 | 
						|
        raise self._not_implemented("setup")
 | 
						|
 | 
						|
    @property
 | 
						|
    def volumes(self):
 | 
						|
        ''' Return a collection of volumes managed by this pool '''
 | 
						|
        return self._volumes_collection
 | 
						|
 | 
						|
    def list_volumes(self):
 | 
						|
        ''' Return a list of volumes managed by this pool '''
 | 
						|
        raise self._not_implemented("list_volumes")
 | 
						|
 | 
						|
    def get_volume(self, vid):
 | 
						|
        ''' Return a volume with *vid* from this pool
 | 
						|
 | 
						|
        :raise KeyError: if no volume is found
 | 
						|
        '''
 | 
						|
        raise self._not_implemented("get_volume")
 | 
						|
 | 
						|
    def included_in(self, app):
 | 
						|
        ''' Check if this pool is physically included in another one
 | 
						|
 | 
						|
        This works on best-effort basis, because one pool driver may not know
 | 
						|
        all the other drivers.
 | 
						|
 | 
						|
        :param app: Qubes() object to lookup other pools in
 | 
						|
        :returns pool or None
 | 
						|
        '''
 | 
						|
        pass
 | 
						|
 | 
						|
    @property
 | 
						|
    def size(self):
 | 
						|
        ''' Storage pool size in bytes, or None if unknown '''
 | 
						|
        pass
 | 
						|
 | 
						|
    @property
 | 
						|
    def usage(self):
 | 
						|
        ''' Space used in the pool in bytes, or None if unknown '''
 | 
						|
        pass
 | 
						|
 | 
						|
    def _not_implemented(self, method_name):
 | 
						|
        ''' Helper for emitting helpful `NotImplementedError` exceptions '''
 | 
						|
        msg = "Pool driver {!s} has {!s}() not implemented"
 | 
						|
        msg = msg.format(str(self.__class__.__name__), method_name)
 | 
						|
        return NotImplementedError(msg)
 | 
						|
 | 
						|
 | 
						|
@asyncio.coroutine
 | 
						|
def _wait_and_reraise(futures):
 | 
						|
    if futures:
 | 
						|
        done, _ = yield from asyncio.wait(futures)
 | 
						|
        for task in done:  # (re-)raise first exception in line
 | 
						|
            task.result()
 | 
						|
 | 
						|
 | 
						|
def _sanitize_config(config):
 | 
						|
    ''' Helper function to convert types to appropriate strings
 | 
						|
    '''  # FIXME: find another solution for serializing basic types
 | 
						|
    result = {}
 | 
						|
    for key, value in config.items():
 | 
						|
        if isinstance(value, bool):
 | 
						|
            if value:
 | 
						|
                result[key] = 'True'
 | 
						|
        else:
 | 
						|
            result[key] = str(value)
 | 
						|
    return result
 | 
						|
 | 
						|
 | 
						|
def pool_drivers():
 | 
						|
    """ Return a list of EntryPoints names """
 | 
						|
    return [ep.name
 | 
						|
            for ep in pkg_resources.iter_entry_points(STORAGE_ENTRY_POINT)]
 | 
						|
 | 
						|
 | 
						|
def driver_parameters(name):
 | 
						|
    ''' Get __init__ parameters from a driver with out `self` & `name`. '''
 | 
						|
    init_function = qubes.utils.get_entry_point_one(
 | 
						|
        qubes.storage.STORAGE_ENTRY_POINT, name).__init__
 | 
						|
    signature = inspect.signature(init_function)
 | 
						|
    params = signature.parameters.keys()
 | 
						|
    ignored_params = ['self', 'name', 'kwargs']
 | 
						|
    return [p for p in params if p not in ignored_params]
 | 
						|
 | 
						|
 | 
						|
def isodate(seconds):
 | 
						|
    ''' Helper method which returns an iso date '''
 | 
						|
    return datetime.utcfromtimestamp(seconds).isoformat("T")
 | 
						|
 | 
						|
def search_pool_containing_dir(pools, dir_path):
 | 
						|
    ''' Helper function looking for a pool containing given directory.
 | 
						|
 | 
						|
    This is useful for implementing Pool.included_in method
 | 
						|
    '''
 | 
						|
 | 
						|
    real_dir_path = os.path.realpath(dir_path)
 | 
						|
 | 
						|
    # prefer filesystem pools
 | 
						|
    for pool in pools:
 | 
						|
        if hasattr(pool, 'dir_path'):
 | 
						|
            pool_real_dir_path = os.path.realpath(pool.dir_path)
 | 
						|
            if os.path.commonpath([pool_real_dir_path, real_dir_path]) == \
 | 
						|
               pool_real_dir_path:
 | 
						|
                return pool
 | 
						|
 | 
						|
    # then look for lvm
 | 
						|
    for pool in pools:
 | 
						|
        if hasattr(pool, 'thin_pool') and hasattr(pool, 'volume_group'):
 | 
						|
            if (pool.volume_group, pool.thin_pool) == \
 | 
						|
                    DirectoryThinPool.thin_pool(real_dir_path):
 | 
						|
                return pool
 | 
						|
 | 
						|
    return None
 | 
						|
 | 
						|
 | 
						|
class VmCreationManager:
 | 
						|
    ''' A `ContextManager` which cleans up if volume creation fails.
 | 
						|
    '''  # pylint: disable=too-few-public-methods
 | 
						|
    def __init__(self, vm):
 | 
						|
        self.vm = vm
 | 
						|
 | 
						|
    def __enter__(self):
 | 
						|
        pass
 | 
						|
 | 
						|
    def __exit__(self, type, value, tb):  # pylint: disable=redefined-builtin
 | 
						|
        if type is not None and value is not None and tb is not None:
 | 
						|
            for volume in self.vm.volumes.values():
 | 
						|
                try:
 | 
						|
                    volume.remove()
 | 
						|
                except Exception:  # pylint: disable=broad-except
 | 
						|
                    pass
 | 
						|
            os.rmdir(self.vm.dir_path)
 | 
						|
 | 
						|
# pylint: disable=too-few-public-methods
 | 
						|
class DirectoryThinPool:
 | 
						|
    '''The thin pool containing the device of given filesystem'''
 | 
						|
    _thin_pool = {}
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _init(cls, dir_path):
 | 
						|
        '''Find out the thin pool containing given filesystem'''
 | 
						|
        if dir_path not in cls._thin_pool:
 | 
						|
            cls._thin_pool[dir_path] = None, None
 | 
						|
 | 
						|
            try:
 | 
						|
                fs_stat = os.stat(dir_path)
 | 
						|
                fs_major = (fs_stat.st_dev & 0xff00) >> 8
 | 
						|
                fs_minor = fs_stat.st_dev & 0xff
 | 
						|
 | 
						|
                sudo = []
 | 
						|
                if os.getuid():
 | 
						|
                    sudo = ['sudo']
 | 
						|
                root_table = subprocess.check_output(sudo + ["dmsetup",
 | 
						|
                    "-j", str(fs_major), "-m", str(fs_minor),
 | 
						|
                    "table"], stderr=subprocess.DEVNULL)
 | 
						|
 | 
						|
                _start, _sectors, target_type, target_args = \
 | 
						|
                    root_table.decode().split(" ", 3)
 | 
						|
                if target_type == "thin":
 | 
						|
                    thin_pool_devnum, _thin_pool_id = target_args.split(" ")
 | 
						|
                    with open("/sys/dev/block/{}/dm/name"
 | 
						|
                        .format(thin_pool_devnum), "r") as thin_pool_tpool_f:
 | 
						|
                        thin_pool_tpool = thin_pool_tpool_f.read().rstrip('\n')
 | 
						|
                    if thin_pool_tpool.endswith("-tpool"):
 | 
						|
                        volume_group, thin_pool, _tpool = \
 | 
						|
                            thin_pool_tpool.rsplit("-", 2)
 | 
						|
                        cls._thin_pool[dir_path] = volume_group, thin_pool
 | 
						|
            except:  # pylint: disable=bare-except
 | 
						|
                pass
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def thin_pool(cls, dir_path):
 | 
						|
        '''Thin tuple (volume group, pool name) containing given filesystem'''
 | 
						|
        cls._init(dir_path)
 | 
						|
        return cls._thin_pool[dir_path]
 |