| # -*- coding: utf-8 -*- |
| # Copyright 2016 The Chromium OS Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| """Script for VM Management.""" |
| |
| from __future__ import print_function |
| |
| import os |
| |
| from chromite.lib import commandline |
| from chromite.lib import cros_build_lib |
| from chromite.lib import cros_logging as logging |
| from chromite.lib import osutils |
| from chromite.lib import remote_access |
| from chromite.lib import retry_util |
| |
| |
| class VMError(Exception): |
| """Exception for VM failures.""" |
| |
| def __init__(self, message): |
| super(VMError, self).__init__() |
| logging.error(message) |
| |
| |
| class VM(object): |
| """Class for managing a VM.""" |
| |
| SSH_PORT = 9222 |
| |
| def __init__(self, image_path=None, qemu_path=None, enable_kvm=True, |
| display=True, ssh_port=SSH_PORT, dry_run=False): |
| """Initialize VM. |
| |
| Args: |
| image_path: path of vm image. |
| qemu_path: path to qemu binary. |
| enable_kvm: enable kvm (kernel support for virtualization). |
| display: display video output. |
| ssh_port: ssh port to use. |
| dry_run: disable VM commands. |
| """ |
| |
| self.qemu_path = qemu_path |
| self.enable_kvm = enable_kvm |
| # We don't need sudo access for software emulation or if /dev/kvm is |
| # writeable. |
| self.use_sudo = enable_kvm and not os.access('/dev/kvm', os.W_OK) |
| self.display = display |
| self.image_path = image_path |
| self.ssh_port = ssh_port |
| self.dry_run = dry_run |
| |
| self.vm_dir = os.path.join(osutils.GetGlobalTempDir(), 'cros_vm') |
| if os.path.exists(self.vm_dir): |
| # For security, ensure that vm_dir is not a symlink, and is owned by us or |
| # by root. |
| assert not os.path.islink(self.vm_dir), \ |
| 'VM state dir is misconfigured; please recreate: %s' % self.vm_dir |
| st_uid = os.stat(self.vm_dir).st_uid |
| assert st_uid == 0 or st_uid == os.getuid(), \ |
| 'VM state dir is misconfigured; please recreate: %s' % self.vm_dir |
| |
| self.pidfile = os.path.join(self.vm_dir, 'kvm.pid') |
| self.kvm_monitor = os.path.join(self.vm_dir, 'kvm.monitor') |
| self.kvm_pipe_in = '%s.in' % self.kvm_monitor # to KVM |
| self.kvm_pipe_out = '%s.out' % self.kvm_monitor # from KVM |
| self.kvm_serial = '%s.serial' % self.kvm_monitor |
| |
| self.remote = remote_access.RemoteDevice(remote_access.LOCALHOST, |
| port=ssh_port) |
| |
| # TODO(achuith): support nographics, snapshot, mem_path, usb_passthrough, |
| # moblab, etc. |
| |
| |
| def _RunCommand(self, *args, **kwargs): |
| """Use SudoRunCommand or RunCommand as necessary.""" |
| if self.use_sudo: |
| return cros_build_lib.SudoRunCommand(*args, **kwargs) |
| else: |
| return cros_build_lib.RunCommand(*args, **kwargs) |
| |
| def _CleanupFiles(self, recreate): |
| """Cleanup vm_dir. |
| |
| Args: |
| recreate: recreate vm_dir. |
| """ |
| osutils.RmDir(self.vm_dir, ignore_missing=True, sudo=self.use_sudo) |
| if recreate: |
| osutils.SafeMakedirs(self.vm_dir) |
| |
| def PerformAction(self, start=False, stop=False, cmd=None): |
| """Performs an action, one of start, stop, or run a command in the VM. |
| |
| Args: |
| start: start the VM. |
| stop: stop the VM. |
| cmd: list or scalar command to run in the VM. |
| |
| Returns: |
| cmd output. |
| """ |
| |
| if not start and not stop and not cmd: |
| raise VMError('Must specify one of start, stop, or cmd.') |
| if start: |
| self.Start() |
| if stop: |
| self.Stop() |
| if cmd: |
| return self.RemoteCommand(cmd.split()) |
| |
| def Start(self): |
| """Start the VM.""" |
| |
| self.Stop() |
| |
| logging.debug('Start VM') |
| if not self.qemu_path: |
| self.qemu_path = osutils.Which('qemu-system-x86_64') |
| if not self.qemu_path: |
| raise VMError('qemu not found.') |
| logging.debug('qemu path=%s', self.qemu_path) |
| |
| if not self.image_path: |
| self.image_path = os.environ.get('VM_IMAGE_PATH', '') |
| logging.debug('vm image path=%s', self.image_path) |
| if not self.image_path or not os.path.exists(self.image_path): |
| raise VMError('VM image path %s does not exist.' % self.image_path) |
| |
| self._CleanupFiles(recreate=True) |
| # Make sure we can read these files later on by creating them as ourselves. |
| osutils.Touch(self.kvm_serial) |
| for pipe in [self.kvm_pipe_in, self.kvm_pipe_out]: |
| os.mkfifo(pipe, 0600) |
| osutils.Touch(self.pidfile) |
| |
| args = [self.qemu_path, '-m', '2G', '-smp', '4', '-vga', 'cirrus', |
| '-daemonize', |
| '-pidfile', self.pidfile, |
| '-chardev', 'pipe,id=control_pipe,path=%s' % self.kvm_monitor, |
| '-serial', 'file:%s' % self.kvm_serial, |
| '-mon', 'chardev=control_pipe', |
| '-net', 'nic,model=virtio', |
| '-net', 'user,hostfwd=tcp:127.0.0.1:%d-:22' % self.ssh_port, |
| '-drive', 'file=%s,index=0,media=disk,cache=unsafe' |
| % self.image_path] |
| if self.enable_kvm: |
| args.append('-enable-kvm') |
| if not self.display: |
| args.extend(['-display', 'none']) |
| logging.info(cros_build_lib.CmdToStr(args)) |
| logging.info('Pid file: %s', self.pidfile) |
| if not self.dry_run: |
| self._RunCommand(args) |
| |
| def _GetVMPid(self): |
| """Get the pid of the VM. |
| |
| Returns: |
| pid of the VM. |
| """ |
| if not os.path.exists(self.vm_dir): |
| logging.debug('%s not present.', self.vm_dir) |
| return 0 |
| |
| if not os.path.exists(self.pidfile): |
| logging.info('%s does not exist.', self.pidfile) |
| return 0 |
| |
| pid = osutils.ReadFile(self.pidfile).rstrip() |
| if not pid.isdigit(): |
| # Ignore blank/empty files. |
| if pid: |
| logging.error('%s in %s is not a pid.', pid, self.pidfile) |
| return 0 |
| |
| return int(pid) |
| |
| def IsRunning(self): |
| """Returns True if there's a running VM. |
| |
| Returns: |
| True if there's a running VM. |
| """ |
| pid = self._GetVMPid() |
| if not pid: |
| return False |
| |
| # Make sure the process actually exists. |
| return os.path.isdir('/proc/%i' % pid) |
| |
| def Stop(self): |
| """Stop the VM.""" |
| logging.debug('Stop VM') |
| |
| pid = self._GetVMPid() |
| if pid: |
| logging.info('Killing %d.', pid) |
| if not self.dry_run: |
| self._RunCommand(['kill', '-9', str(pid)], error_code_ok=True) |
| |
| self._CleanupFiles(recreate=False) |
| |
| def _WaitForProcs(self): |
| """Wait for expected processes to launch.""" |
| class _TooFewPidsException(Exception): |
| """Exception for _GetRunningPids to throw.""" |
| |
| def _GetRunningPids(exe, numpids): |
| pids = self.remote.GetRunningPids(exe, full_path=False) |
| logging.info('%s pids: %s', exe, repr(pids)) |
| if len(pids) < numpids: |
| raise _TooFewPidsException() |
| |
| def _WaitForProc(exe, numpids): |
| try: |
| retry_util.RetryException( |
| exception=_TooFewPidsException, |
| max_retry=20, |
| functor=lambda: _GetRunningPids(exe, numpids), |
| sleep=2) |
| except _TooFewPidsException: |
| raise VMError('_WaitForProcs failed: timed out while waiting for ' |
| '%d %s processes to start.' % (numpids, exe)) |
| |
| # We could also wait for session_manager, nacl_helper, etc, but chrome is |
| # the long pole. We expect the parent, 2 zygotes, gpu-process, renderer. |
| # This could potentially break with Mustash. |
| _WaitForProc('chrome', 5) |
| |
| def WaitForBoot(self): |
| """Wait for the VM to boot up. |
| |
| Wait for ssh connection to become active, and wait for all expected chrome |
| processes to be launched. |
| """ |
| if not os.path.exists(self.vm_dir): |
| self.Start() |
| |
| try: |
| result = retry_util.RetryException( |
| exception=remote_access.SSHConnectionError, |
| max_retry=10, |
| functor=lambda: self.RemoteCommand(cmd=['echo']), |
| sleep=5) |
| except remote_access.SSHConnectionError: |
| raise VMError('WaitForBoot timed out trying to connect to VM.') |
| |
| if result.returncode != 0: |
| raise VMError('WaitForBoot failed: %s.' % result.error) |
| |
| self._WaitForProcs() |
| |
| def RemoteCommand(self, cmd): |
| """Run a remote command in the VM. |
| |
| Args: |
| cmd: command to run, of list type. |
| """ |
| if not isinstance(cmd, list): |
| raise VMError('cmd must be a list.') |
| |
| if not self.dry_run: |
| return self.remote.RunCommand(cmd, debug_level=logging.INFO, |
| combine_stdout_stderr=True, |
| log_output=True, |
| error_code_ok=True) |
| |
| def ParseCommandLine(argv): |
| """Parse the command line. |
| |
| Args: |
| argv: Command arguments. |
| |
| Returns: |
| List of parsed args. |
| """ |
| parser = commandline.ArgumentParser(description=__doc__) |
| parser.add_argument('--start', action='store_true', default=False, |
| help='Start the VM.') |
| parser.add_argument('--stop', action='store_true', default=False, |
| help='Stop the VM.') |
| parser.add_argument('--cmd', help='Run this command in the VM.') |
| parser.add_argument('--image-path', type='path', |
| help='Path to VM image to launch with --start.') |
| parser.add_argument('--qemu-path', type='path', |
| help='Path of qemu binary to launch with --start.') |
| parser.add_argument('--disable-kvm', dest='enable_kvm', |
| action='store_false', default=True, |
| help='Disable KVM, use software emulation.') |
| parser.add_argument('--no-display', dest='display', |
| action='store_false', default=True, |
| help='Do not display video output.') |
| parser.add_argument('--ssh-port', type=int, default=VM.SSH_PORT, |
| help='ssh port to communicate with VM.') |
| parser.add_argument('--dry-run', action='store_true', default=False, |
| help='dry run for debugging.') |
| return parser.parse_args(argv) |
| |
| |
| def main(argv): |
| args = ParseCommandLine(argv) |
| vm = VM(image_path=args.image_path, qemu_path=args.qemu_path, |
| enable_kvm=args.enable_kvm, display=args.display, |
| ssh_port=args.ssh_port, dry_run=args.dry_run) |
| vm.PerformAction(start=args.start, stop=args.stop, cmd=args.cmd) |
