#!/usr/bin/python2 # # The Qubes OS Project, http://www.qubes-os.org # # Copyright (C) 2016 Bahtiar `kalkin-` Gadimov # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty 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. # ''' Manage pools and volumes managed by the 'lvm_thin' driver. ''' from __future__ import print_function import argparse import logging import subprocess import sys import time import lvm # pylint: disable=import-error log = logging.getLogger('qubes.storage.lvm') def pool_exists(args): """ Check if given name is an lvm thin volume. """ # TODO Implement a faster and proper working version pool_exists vg_name, thin_pool_name = args.pool_id.split('/', 1) volume_group = lvm.vgOpen(vg_name) for p in volume_group.listLVs(): if p.getAttr()[0] == 't' and p.getName() == thin_pool_name: volume_group.close() return True volume_group.close() return False def volume_exists(volume): """ Check if the given volume exists and is a thin volume """ log.debug("Checking if the %s thin volume exists", volume) assert volume is not None vg_name, volume_name = volume.split('/', 1) volume_group = lvm.vgOpen(vg_name) for p in volume_group.listLVs(): if p.getAttr()[0] == 'V' and p.getName() == volume_name: volume_group.close() return True volume_group.close() return False def remove_volume(args): """ Tries to remove the specified logical volume. If the removal fails it will try up to 3 times waiting 1, 2 and 3 seconds between tries. Most of the time this function fails if some process still has the volume locked. """ img = args.name if not volume_exists(img): log.info("Expected to remove %s, but volume does not exist", img) return tries = 1 successful = False cmd = ['lvremove', '-f', img] while tries <= 3 and not successful: log.info("Trying to remove LVM %s", img) try: output = subprocess.check_output(cmd, stderr=subprocess.STDOUT) log.debug(output) successful = True except subprocess.CalledProcessError: successful = False if successful: break else: time.sleep(tries) tries += 1 if not successful: log.error('Could not remove volume ' + img) def clone_volume(args): """ Calls lvcreate and creates new snapshot. """ old = args.source new_name = args.destination cmd = ["lvcreate", "-kn", "-ay", "-s", old, "-n", new_name] return subprocess.call(cmd) def new_volume(args): ''' Creates a new volume in the specified thin pool, formated with ext4 ''' thin_pool = args.pool_id name = args.name size = args.size log.info('Creating new Thin LVM %s in %s VG %s bytes', name, thin_pool, size) cmd = ['lvcreate', '-T', thin_pool, '-kn', '-ay', '-n', name, '-V', str(size) + 'B'] return subprocess.call(cmd) def rename_volume(old_name, new_name): ''' Rename volume ''' log.debug("Renaming LVM %s to %s ", old_name, new_name) retcode = subprocess.call(["lvrename", old_name, new_name]) if retcode != 0: raise IOError("Error renaming LVM %s to %s " % (old_name, new_name)) return new_name def init_pool_parser(sub_parsers): ''' Initialize pool subparser ''' pool_parser = sub_parsers.add_parser( 'pool', help="Exit with exit code 0 if pool exists") pool_parser.add_argument('pool_id', metavar='VG/POOL', help="volume_group/pool_name") pool_parser.set_defaults(func=pool_exists) def init_new_parser(sub_parsers): ''' Initialize the 'new' subparser ''' new_parser = sub_parsers.add_parser( 'create', help='Creates a new thin ThinPoolLogicalVolume') new_parser.add_argument('pool_id', metavar='VG/POOL', help="volume_group/pool_name") new_parser.add_argument('name', help='name of the new ThinPoolLogicalVolume') new_parser.add_argument( 'size', help='size in bytes of the new ThinPoolLogicalVolume') new_parser.set_defaults(func=new_volume) def init_import_parser(sub_parsers): ''' Initialize import subparser ''' import_parser = sub_parsers.add_parser( 'import', help='sparse copy data from stdin to a thin volume') import_parser.add_argument('name', metavar='VG/VID', help='volume_group/volume_name') import_parser.set_defaults(func=import_volume) def init_clone_parser(sub_parsers): ''' Initialize clone subparser ''' clone_parser = sub_parsers.add_parser( 'clone', help='sparse copy data from stdin to a thin volume') clone_parser.add_argument('source', metavar='VG/VID', help='volume_group/volume_name') clone_parser.add_argument('destination', metavar='VG/VID', help='volume_group/volume_name') clone_parser.set_defaults(func=clone_volume) def import_volume(args): ''' Imports from stdin to a thin volume ''' name = args.name src = sys.stdin blk_size = 4096 zeros = '\x00' * blk_size dst_path = '/dev/%s' % name with open(dst_path, 'wb') as dst: while True: tmp = src.read(blk_size) if not tmp: break elif tmp == zeros: dst.seek(blk_size, 1) else: dst.write(tmp) def list_volumes(args): ''' lists volumes ''' vg_name, _ = args.name.split('/') volume_group = lvm.vgOpen(vg_name) for p in volume_group.listLVs(): if p.getAttr()[0] == 'V': print(vg_name + "/" + p.getName() + ' ' + p.getAttr()) volume_group.close() def init_volumes_parser(sub_parsers): ''' Initialize volumes subparser ''' parser = sub_parsers.add_parser('volumes', help='list volumes in a pool') parser.add_argument('name', metavar='VG/THIN_POOL', help='volume_group/thin_pool_name') parser.set_defaults(func=list_volumes) def init_remove_parser(sub_parsers): ''' Initialize remove subparser ''' remove_parser = sub_parsers.add_parser('remove', help='Removes a LogicalVolume') remove_parser.add_argument('name', metavar='VG/VID', help='volume_group/volume_name') remove_parser.set_defaults(func=remove_volume) def get_parser(): '''Create :py:class:`argparse.ArgumentParser` suitable for :program:`qubes-lvm`. ''' parser = argparse.ArgumentParser(description=__doc__) # pylint: disable=protected-access parser.register('action', 'parsers', argparse._SubParsersAction) sub_parsers = parser.add_subparsers( title='commands', description="For more information see qubes-lvm command -h", dest='command') init_pool_parser(sub_parsers) init_import_parser(sub_parsers) init_new_parser(sub_parsers) init_volumes_parser(sub_parsers) init_remove_parser(sub_parsers) init_clone_parser(sub_parsers) return parser def main(args=None): '''Main routine of :program:`qubes-lvm`.''' args = get_parser().parse_args(args) return args.func(args) if __name__ == '__main__': sys.exit(main())