# pylint: skip-file # # The Qubes OS Project, http://www.qubes-os.org # # Copyright (C) 2010 Rafal Wojtczuk # # 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. # # import ConfigParser import SocketServer import logging import logging.handlers import os import socket import sys import thread import xen.lowlevel.xs import qubes.qmemman import qubes.qmemman.algo import qubes.utils SOCK_PATH = '/var/run/qubes/qmemman.sock' LOG_PATH = '/var/log/qubes/qmemman.log' system_state = qubes.qmemman.SystemState() global_lock = thread.allocate_lock() # If XS_Watcher will # handle meminfo event before @introduceDomain, it will use # incomplete domain list for that and may redistribute memory # allocated to some VM, but not yet used (see #1389). # To fix that, system_state should be updated (refresh domain # list) before processing other changes, every time some process requested # memory for a new VM, before releasing the lock. Then XS_Watcher will check # this flag before processing other event. force_refresh_domain_list = False def only_in_first_list(l1, l2): ret = [] for i in l1: if not i in l2: ret.append(i) return ret def get_domain_meminfo_key(domain_id): return '/local/domain/'+domain_id+'/memory/meminfo' class WatchType(object): def __init__(self, fn, param): self.fn = fn self.param = param class XS_Watcher(object): def __init__(self): self.log = logging.getLogger('qmemman.daemon.xswatcher') self.log.debug('XS_Watcher()') self.handle = xen.lowlevel.xs.xs() self.handle.watch('@introduceDomain', WatchType( XS_Watcher.domain_list_changed, False)) self.handle.watch('@releaseDomain', WatchType( XS_Watcher.domain_list_changed, False)) self.watch_token_dict = {} def domain_list_changed(self, refresh_only=False): """ Check if any domain was created/destroyed. If it was, update appropriate list. Then redistribute memory. :param refresh_only If True, only refresh domain list, do not redistribute memory. In this mode, caller must already hold global_lock. """ self.log.debug('domain_list_changed(only_refresh={!r})'.format( refresh_only)) got_lock = False if not refresh_only: self.log.debug('acquiring global_lock') global_lock.acquire() got_lock = True self.log.debug('global_lock acquired') try: curr = self.handle.ls('', '/local/domain') if curr is None: return # check if domain is really there, it may happen that some empty # directories are left in xenstore curr = filter( lambda x: self.handle.read('', '/local/domain/{}/domid'.format(x) ) is not None, curr ) self.log.debug('curr={!r}'.format(curr)) for i in only_in_first_list(curr, self.watch_token_dict.keys()): # new domain has been created watch = WatchType(XS_Watcher.meminfo_changed, i) self.watch_token_dict[i] = watch self.handle.watch(get_domain_meminfo_key(i), watch) system_state.add_domain(i) for i in only_in_first_list(self.watch_token_dict.keys(), curr): # domain destroyed self.handle.unwatch(get_domain_meminfo_key(i), self.watch_token_dict[i]) self.watch_token_dict.pop(i) system_state.del_domain(i) finally: if got_lock: global_lock.release() self.log.debug('global_lock released') if not refresh_only: system_state.do_balance() def meminfo_changed(self, domain_id): self.log.debug('meminfo_changed(domain_id={!r})'.format(domain_id)) untrusted_meminfo_key = self.handle.read( '', get_domain_meminfo_key(domain_id)) if untrusted_meminfo_key == None or untrusted_meminfo_key == '': return self.log.debug('acquiring global_lock') global_lock.acquire() self.log.debug('global_lock acquired') if force_refresh_domain_list: self.domain_list_changed(refresh_only=True) system_state.refresh_meminfo(domain_id, untrusted_meminfo_key) global_lock.release() self.log.debug('global_lock released') def watch_loop(self): self.log.debug('watch_loop()') while True: result = self.handle.read_watch() self.log.debug('watch_loop result={!r}'.format(result)) token = result[1] token.fn(self, token.param) class QMemmanReqHandler(SocketServer.BaseRequestHandler): """ The RequestHandler class for our server. It is instantiated once per connection to the server, and must override the handle() method to implement communication to the client. """ def handle(self): self.log = logging.getLogger('qmemman.daemon.reqhandler') got_lock = False try: # self.request is the TCP socket connected to the client while True: self.data = self.request.recv(1024).strip() self.log.debug('data={!r}'.format(self.data)) if len(self.data) == 0: self.log.info('EOF') if got_lock: global force_refresh_domain_list force_refresh_domain_list = True return # XXX something is wrong here: return without release? if got_lock: self.log.warning('Second request over qmemman.sock?') return self.log.debug('acquiring global_lock') global_lock.acquire() self.log.debug('global_lock acquired') got_lock = True if system_state.do_balloon(int(self.data)): resp = "OK\n" else: resp = "FAIL\n" self.log.debug('resp={!r}'.format(resp)) self.request.send(resp) except BaseException as e: self.log.exception( "exception while handling request: {!r}".format(e)) finally: if got_lock: global_lock.release() self.log.debug('global_lock released') parser = qubes.tools.QubesArgumentParser(want_app=False) parser.add_argument('--config', '-c', metavar='FILE', action='store', default='/etc/qubes/qmemman.conf', help='qmemman config file') parser.add_argument('--foreground', action='store_true', default=False, help='do not close stdio') def main(): args = parser.parse_args() # setup logging ha_syslog = logging.handlers.SysLogHandler('/dev/log') ha_syslog.setFormatter( logging.Formatter('%(name)s[%(process)d]: %(message)s')) logging.root.addHandler(ha_syslog) # leave log for backwards compatibility ha_file = logging.FileHandler(LOG_PATH) ha_file.setFormatter( logging.Formatter('%(asctime)s %(name)s[%(process)d]: %(message)s')) logging.root.addHandler(ha_file) if args.foreground: ha_stderr = logging.StreamHandler(sys.stderr) ha_file.setFormatter( logging.Formatter('%(asctime)s %(name)s[%(process)d]: %(message)s')) logging.root.addHandler(ha_stderr) else: # close io sys.stdout.close() sys.stderr.close() sys.stdin.close() logging.root.setLevel(parser.get_loglevel_from_verbosity(args)) log = logging.getLogger('qmemman.daemon') config = ConfigParser.SafeConfigParser({ 'vm-min-mem': str(qubes.qmemman.algo.MIN_PREFMEM), 'dom0-mem-boost': str(qubes.qmemman.algo.DOM0_MEM_BOOST), 'cache-margin-factor': str(qubes.qmemman.algo.CACHE_FACTOR) }) config.read(args.config) if config.has_section('global'): qubes.qmemman.algo.MIN_PREFMEM = \ qubes.utils.parse_size(config.get('global', 'vm-min-mem')) qubes.qmemman.algo.DOM0_MEM_BOOST = \ qubes.utils.parse_size(config.get('global', 'dom0-mem-boost')) qubes.qmemman.algo.CACHE_FACTOR = \ config.getfloat('global', 'cache-margin-factor') log.info('MIN_PREFMEM={algo.MIN_PREFMEM}' ' DOM0_MEM_BOOST={algo.DOM0_MEM_BOOST}' ' CACHE_FACTOR={algo.CACHE_FACTOR}'.format( algo=qubes.qmemman.algo)) try: os.unlink(SOCK_PATH) except: pass log.debug('instantiating server') os.umask(0) server = SocketServer.UnixStreamServer(SOCK_PATH, QMemmanReqHandler) os.umask(0o077) # notify systemd nofity_socket = os.getenv('NOTIFY_SOCKET') if nofity_socket: log.debug('notifying systemd') s = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM) if nofity_socket.startswith('@'): nofity_socket = '\0%s' % nofity_socket[1:] s.connect(nofity_socket) s.sendall("READY=1") s.close() thread.start_new_thread(server.serve_forever, ()) XS_Watcher().watch_loop()