From 5cce87c7d2f1dc5b65f147d2920ea5d8826c2492 Mon Sep 17 00:00:00 2001 From: Marek Marczykowski Date: Fri, 10 Jun 2011 18:36:20 +0200 Subject: [PATCH] dom0: Introduce qvm-revert-template-changes tool --- dom0/qvm-tools/qvm-revert-template-changes | 140 +++++++++++++++++++++ 1 file changed, 140 insertions(+) create mode 100755 dom0/qvm-tools/qvm-revert-template-changes diff --git a/dom0/qvm-tools/qvm-revert-template-changes b/dom0/qvm-tools/qvm-revert-template-changes new file mode 100755 index 00000000..81dfbae7 --- /dev/null +++ b/dom0/qvm-tools/qvm-revert-template-changes @@ -0,0 +1,140 @@ +#!/usr/bin/python2.6 +# +# The Qubes OS Project, http://www.qubes-os.org +# +# Copyright (C) 2011 Marek Marczykowski +# +# 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. +# +# + +from qubes.qubes import QubesVmCollection +from qubes.qubes import QubesException +from optparse import OptionParser +import subprocess +import os +import time +import glob + +def main(): + usage = "usage: %prog [options] " + parser = OptionParser (usage) + parser.add_option ("--force", action="store_true", dest="force", default=False, + help="Do not prompt for comfirmation") + + (options, args) = parser.parse_args () + if (len (args) != 1): + parser.error ("You must specify TemplateVM name!") + vmname = args[0] + + if os.geteuid() != 0: + print "ERROR: This tool must be run as root!" + exit(1) + + qvm_collection = QubesVmCollection() + qvm_collection.lock_db_for_reading() + qvm_collection.load() + qvm_collection.unlock_db() + + vm = qvm_collection.get_vm_by_name(vmname) + if vm is None: + print "A VM with the name '{0}' does not exist in the system.".format(vmname) + exit(1) + + if not vm.is_template(): + print "A VM '{0}' is not template.".format(vmname) + exit(1) + + if vm.is_running(): + print "You must stop VM first." + exit(1) + + oldcow_img = vm.rootcow_img + '.old' + oldcow_stat = os.stat(oldcow_img) + oldcow_time_str = time.strftime("%F %T", time.gmtime(oldcow_stat.st_mtime)) + + root_stat = os.stat(vm.root_img) + old_dmdev = "/dev/mapper/snapshot-{0:x}:{1}-{2:x}:{3}".format( + root_stat[2], root_stat[1], + oldcow_stat[2], oldcow_stat[1]) + + snapshots = glob.glob('/dev/mapper/snapshot-{0:x}:{1}-*'.format(root_stat[2], root_stat[1])) + snapshot_present = False + for dev in snapshots: + if dev == old_dmdev: + snapshot_present = True + else: + print "ERROR: You must shutdown all VMs running system older/newer than last good one." + exit(1) + + root_blocks = os.path.getsize(vm.root_img)/512 + if not snapshot_present: + p = subprocess.Popen (["/etc/xen/scripts/block-snapshot", "prepare", + "snapshot", "{0}:{1}".format(vm.root_img, oldcow_img)], + stdout=subprocess.PIPE) + result = p.communicate() + if result[0].strip() != old_dmdev: + print "ERROR: Cannot create snapshot device ({0} != {1})".format( + result[0].strip(), old_dmdev) + exit(1) + + + print "INFO: Reverting template changes done at {0}".format(oldcow_time_str) + if not options.force: + prompt = raw_input ("Do you want to proceed? [y/N] ") + if not (prompt == "y" or prompt == "Y"): + exit (0) + + p = subprocess.Popen(["/sbin/dmsetup", "table", old_dmdev], stdout=subprocess.PIPE) + result = p.communicate() + dm_table = result[0] + dm_table_elements = dm_table.split(' ') + if dm_table_elements[2] != 'snapshot': + print "ERROR: Unexpected device-mapper type ({0}). Template changes reverting already running".format(dm_table_elements[2]) + exit(1) + + dm_table_elements[2] = 'snapshot-merge' + dm_table = ' '.join(dm_table_elements) + subprocess.check_call(["/sbin/dmsetup", "reload", old_dmdev, "--table", dm_table]) + # Reload new table into LIVE slot + subprocess.check_call(["/sbin/dmsetup", "suspend", old_dmdev]) + subprocess.check_call(["/sbin/dmsetup", "resume", old_dmdev]) + # Wait to snapshot merge completed + while True: + p = subprocess.Popen(["/sbin/dmsetup", "status", old_dmdev], stdout=subprocess.PIPE) + result = p.communicate() + status_details = result[0].split(' ') + blocks_used = status_details[3].split('/')[0] + if int(blocks_used) == int(status_details[4]): + break + print "\r-> Reverting template changes: {0} of {1} left".format(blocks_used, root_blocks), + time.sleep(1) + print "\r-> Reverting template changes: done".format(blocks_used, root_blocks) + + dm_table_elements[2] = 'snapshot' + dm_table = ' '.join(dm_table_elements) + subprocess.check_call(["/sbin/dmsetup", "reload", old_dmdev, "--table", dm_table]) + # Reload new table into LIVE slot + subprocess.check_call(["/sbin/dmsetup", "suspend", old_dmdev]) + subprocess.check_call(["/sbin/dmsetup", "resume", old_dmdev]) + + subprocess.check_call(["/etc/xen/scripts/block-snapshot", "cleanup", + "snapshot", old_dmdev]) + + os.rename(oldcow_img, vm.rootcow_img) + exit(0) + + +main()