Coverage for drivers/blktap2.py : 40%

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1#!/usr/bin/python3
2#
3# Copyright (C) Citrix Systems Inc.
4#
5# This program is free software; you can redistribute it and/or modify
6# it under the terms of the GNU Lesser General Public License as published
7# by the Free Software Foundation; version 2.1 only.
8#
9# This program is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12# GNU Lesser General Public License for more details.
13#
14# You should have received a copy of the GNU Lesser General Public License
15# along with this program; if not, write to the Free Software Foundation, Inc.,
16# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17#
18# blktap2: blktap/tapdisk management layer
19#
20import grp
21import os
22import re
23import stat
24import time
25import copy
26from lock import Lock
27import util
28import xmlrpc.client
29import http.client
30import errno
31import signal
32import subprocess
33import syslog as _syslog
34import glob
35import json
36import xs_errors
37import XenAPI # pylint: disable=import-error
38import scsiutil
39from syslog import openlog, syslog
40from stat import * # S_ISBLK(), ...
41import nfs
43import resetvdis
44import vhdutil
45import lvhdutil
47import VDI as sm
49# For RRDD Plugin Registration
50from xmlrpc.client import ServerProxy, Transport
51from socket import socket, AF_UNIX, SOCK_STREAM
53try:
54 from linstorvolumemanager import log_drbd_openers
55 LINSTOR_AVAILABLE = True
56except ImportError:
57 LINSTOR_AVAILABLE = False
59PLUGIN_TAP_PAUSE = "tapdisk-pause"
61SOCKPATH = "/var/xapi/xcp-rrdd"
63NUM_PAGES_PER_RING = 32 * 11
64MAX_FULL_RINGS = 8
65POOL_NAME_KEY = "mem-pool"
66POOL_SIZE_KEY = "mem-pool-size-rings"
68ENABLE_MULTIPLE_ATTACH = "/etc/xensource/allow_multiple_vdi_attach"
69NO_MULTIPLE_ATTACH = not (os.path.exists(ENABLE_MULTIPLE_ATTACH))
72def locking(excType, override=True):
73 def locking2(op):
74 def wrapper(self, *args):
75 self.lock.acquire()
76 try:
77 try:
78 ret = op(self, * args)
79 except (util.CommandException, util.SMException, XenAPI.Failure) as e:
80 util.logException("BLKTAP2:%s" % op)
81 msg = str(e)
82 if isinstance(e, util.CommandException):
83 msg = "Command %s failed (%s): %s" % \
84 (e.cmd, e.code, e.reason)
85 if override:
86 raise xs_errors.XenError(excType, opterr=msg)
87 else:
88 raise
89 except:
90 util.logException("BLKTAP2:%s" % op)
91 raise
92 finally:
93 self.lock.release() 93 ↛ exitline 93 didn't except from function 'wrapper', because the raise on line 86 wasn't executed or the raise on line 88 wasn't executed or the raise on line 91 wasn't executed
94 return ret
95 return wrapper
96 return locking2
99class RetryLoop(object):
101 def __init__(self, backoff, limit):
102 self.backoff = backoff
103 self.limit = limit
105 def __call__(self, f):
107 def loop(*__t, **__d):
108 attempt = 0
110 while True:
111 attempt += 1
113 try:
114 return f( * __t, ** __d)
116 except self.TransientFailure as e:
117 e = e.exception
119 if attempt >= self.limit: 119 ↛ 120line 119 didn't jump to line 120, because the condition on line 119 was never true
120 raise e
122 time.sleep(self.backoff)
124 return loop
126 class TransientFailure(Exception):
127 def __init__(self, exception):
128 self.exception = exception
131def retried(**args):
132 return RetryLoop( ** args)
135class TapCtl(object):
136 """Tapdisk IPC utility calls."""
138 PATH = "/usr/sbin/tap-ctl"
140 def __init__(self, cmd, p):
141 self.cmd = cmd
142 self._p = p
143 self.stdout = p.stdout
145 class CommandFailure(Exception):
146 """TapCtl cmd failure."""
148 def __init__(self, cmd, **info):
149 self.cmd = cmd
150 self.info = info
152 def __str__(self):
153 items = self.info.items()
154 info = ", ".join("%s=%s" % item
155 for item in items)
156 return "%s failed: %s" % (self.cmd, info)
158 # Trying to get a non-existent attribute throws an AttributeError
159 # exception
160 def __getattr__(self, key):
161 if key in self.info: 161 ↛ 163line 161 didn't jump to line 163, because the condition on line 161 was never false
162 return self.info[key]
163 return object.__getattribute__(self, key)
165 @property
166 def has_status(self):
167 return 'status' in self.info
169 @property
170 def has_signal(self):
171 return 'signal' in self.info
173 # Retrieves the error code returned by the command. If the error code
174 # was not supplied at object-construction time, zero is returned.
175 def get_error_code(self):
176 key = 'status'
177 if key in self.info: 177 ↛ 180line 177 didn't jump to line 180, because the condition on line 177 was never false
178 return self.info[key]
179 else:
180 return 0
182 @classmethod
183 def __mkcmd_real(cls, args):
184 return [cls.PATH] + [str(x) for x in args]
186 __next_mkcmd = __mkcmd_real
188 @classmethod
189 def _mkcmd(cls, args):
191 __next_mkcmd = cls.__next_mkcmd
192 cls.__next_mkcmd = cls.__mkcmd_real
194 return __next_mkcmd(args)
196 @classmethod
197 def _call(cls, args, quiet=False, input=None, text_mode=True):
198 """
199 Spawn a tap-ctl process. Return a TapCtl invocation.
200 Raises a TapCtl.CommandFailure if subprocess creation failed.
201 """
202 cmd = cls._mkcmd(args)
204 if not quiet:
205 util.SMlog(cmd)
206 try:
207 p = subprocess.Popen(cmd,
208 stdin=subprocess.PIPE,
209 stdout=subprocess.PIPE,
210 stderr=subprocess.PIPE,
211 close_fds=True,
212 universal_newlines=text_mode)
213 if input:
214 p.stdin.write(input)
215 p.stdin.close()
216 except OSError as e:
217 raise cls.CommandFailure(cmd, errno=e.errno)
219 return cls(cmd, p)
221 def _errmsg(self):
222 output = map(str.rstrip, self._p.stderr)
223 return "; ".join(output)
225 def _wait(self, quiet=False):
226 """
227 Reap the child tap-ctl process of this invocation.
228 Raises a TapCtl.CommandFailure on non-zero exit status.
229 """
230 status = self._p.wait()
231 if not quiet:
232 util.SMlog(" = %d" % status)
234 if status == 0:
235 return
237 info = {'errmsg': self._errmsg(),
238 'pid': self._p.pid}
240 if status < 0:
241 info['signal'] = -status
242 else:
243 info['status'] = status
245 raise self.CommandFailure(self.cmd, ** info)
247 @classmethod
248 def _pread(cls, args, quiet=False, input=None, text_mode=True):
249 """
250 Spawn a tap-ctl invocation and read a single line.
251 """
252 tapctl = cls._call(args=args, quiet=quiet, input=input,
253 text_mode=text_mode)
255 output = tapctl.stdout.readline().rstrip()
257 tapctl._wait(quiet)
258 return output
260 @staticmethod
261 def _maybe(opt, parm):
262 if parm is not None:
263 return [opt, parm]
264 return []
266 @classmethod
267 def __list(cls, minor=None, pid=None, _type=None, path=None):
268 args = ["list"]
269 args += cls._maybe("-m", minor)
270 args += cls._maybe("-p", pid)
271 args += cls._maybe("-t", _type)
272 args += cls._maybe("-f", path)
274 tapctl = cls._call(args, True)
276 for stdout_line in tapctl.stdout:
277 # FIXME: tap-ctl writes error messages to stdout and
278 # confuses this parser
279 if stdout_line == "blktap kernel module not installed\n": 279 ↛ 282line 279 didn't jump to line 282, because the condition on line 279 was never true
280 # This isn't pretty but (a) neither is confusing stdout/stderr
281 # and at least causes the error to describe the fix
282 raise Exception("blktap kernel module not installed: try 'modprobe blktap'")
283 row = {}
285 for field in stdout_line.rstrip().split(' ', 3):
286 bits = field.split('=')
287 if len(bits) == 2: 287 ↛ 299line 287 didn't jump to line 299, because the condition on line 287 was never false
288 key, val = field.split('=')
290 if key in ('pid', 'minor'):
291 row[key] = int(val, 10)
293 elif key in ('state'):
294 row[key] = int(val, 0x10)
296 else:
297 row[key] = val
298 else:
299 util.SMlog("Ignoring unexpected tap-ctl output: %s" % repr(field))
300 yield row
302 tapctl._wait(True)
304 @classmethod
305 @retried(backoff=.5, limit=10)
306 def list(cls, **args):
308 # FIXME. We typically get an EPROTO when uevents interleave
309 # with SM ops and a tapdisk shuts down under our feet. Should
310 # be fixed in SM.
312 try:
313 return list(cls.__list( ** args))
315 except cls.CommandFailure as e:
316 transient = [errno.EPROTO, errno.ENOENT]
317 if e.has_status and e.status in transient:
318 raise RetryLoop.TransientFailure(e)
319 raise
321 @classmethod
322 def allocate(cls, devpath=None):
323 args = ["allocate"]
324 args += cls._maybe("-d", devpath)
325 return cls._pread(args)
327 @classmethod
328 def free(cls, minor):
329 args = ["free", "-m", minor]
330 cls._pread(args)
332 @classmethod
333 @retried(backoff=.5, limit=10)
334 def spawn(cls):
335 args = ["spawn"]
336 try:
337 pid = cls._pread(args)
338 return int(pid)
339 except cls.CommandFailure as ce:
340 # intermittent failures to spawn. CA-292268
341 if ce.status == 1:
342 raise RetryLoop.TransientFailure(ce)
343 raise
345 @classmethod
346 def attach(cls, pid, minor):
347 args = ["attach", "-p", pid, "-m", minor]
348 cls._pread(args)
350 @classmethod
351 def detach(cls, pid, minor):
352 args = ["detach", "-p", pid, "-m", minor]
353 cls._pread(args)
355 @classmethod
356 def _load_key(cls, key_hash, vdi_uuid):
357 import plugins
359 return plugins.load_key(key_hash, vdi_uuid)
361 @classmethod
362 def open(cls, pid, minor, _type, _file, options):
363 params = Tapdisk.Arg(_type, _file)
364 args = ["open", "-p", pid, "-m", minor, '-a', str(params)]
365 text_mode = True
366 input = None
367 if options.get("rdonly"):
368 args.append('-R')
369 if options.get("lcache"):
370 args.append("-r")
371 if options.get("existing_prt") is not None:
372 args.append("-e")
373 args.append(str(options["existing_prt"]))
374 if options.get("secondary"):
375 args.append("-2")
376 args.append(options["secondary"])
377 if options.get("standby"):
378 args.append("-s")
379 if options.get("timeout"):
380 args.append("-t")
381 args.append(str(options["timeout"]))
382 if not options.get("o_direct", True):
383 args.append("-D")
384 if options.get('cbtlog'):
385 args.extend(['-C', options['cbtlog']])
386 if options.get('key_hash'):
387 key_hash = options['key_hash']
388 vdi_uuid = options['vdi_uuid']
389 key = cls._load_key(key_hash, vdi_uuid)
391 if not key:
392 raise util.SMException("No key found with key hash {}".format(key_hash))
393 input = key
394 text_mode = False
395 args.append('-E')
397 cls._pread(args=args, input=input, text_mode=text_mode)
399 @classmethod
400 def close(cls, pid, minor, force=False):
401 args = ["close", "-p", pid, "-m", minor, "-t", "120"]
402 if force:
403 args += ["-f"]
404 cls._pread(args)
406 @classmethod
407 def pause(cls, pid, minor):
408 args = ["pause", "-p", pid, "-m", minor]
409 cls._pread(args)
411 @classmethod
412 def unpause(cls, pid, minor, _type=None, _file=None, mirror=None,
413 cbtlog=None):
414 args = ["unpause", "-p", pid, "-m", minor]
415 if mirror:
416 args.extend(["-2", mirror])
417 if _type and _file:
418 params = Tapdisk.Arg(_type, _file)
419 args += ["-a", str(params)]
420 if cbtlog:
421 args.extend(["-c", cbtlog])
422 cls._pread(args)
424 @classmethod
425 def shutdown(cls, pid):
426 # TODO: This should be a real tap-ctl command
427 os.kill(pid, signal.SIGTERM)
428 os.waitpid(pid, 0)
430 @classmethod
431 def stats(cls, pid, minor):
432 args = ["stats", "-p", pid, "-m", minor]
433 return cls._pread(args, quiet=True)
435 @classmethod
436 def major(cls):
437 args = ["major"]
438 major = cls._pread(args)
439 return int(major)
442class TapdiskExists(Exception):
443 """Tapdisk already running."""
445 def __init__(self, tapdisk):
446 self.tapdisk = tapdisk
448 def __str__(self):
449 return "%s already running" % self.tapdisk
452class TapdiskNotRunning(Exception):
453 """No such Tapdisk."""
455 def __init__(self, **attrs):
456 self.attrs = attrs
458 def __str__(self):
459 items = iter(self.attrs.items())
460 attrs = ", ".join("%s=%s" % attr
461 for attr in items)
462 return "No such Tapdisk(%s)" % attrs
465class TapdiskNotUnique(Exception):
466 """More than one tapdisk on one path."""
468 def __init__(self, tapdisks):
469 self.tapdisks = tapdisks
471 def __str__(self):
472 tapdisks = map(str, self.tapdisks)
473 return "Found multiple tapdisks: %s" % tapdisks
476class TapdiskFailed(Exception):
477 """Tapdisk launch failure."""
479 def __init__(self, arg, err):
480 self.arg = arg
481 self.err = err
483 def __str__(self):
484 return "Tapdisk(%s): %s" % (self.arg, self.err)
486 def get_error(self):
487 return self.err
490class TapdiskInvalidState(Exception):
491 """Tapdisk pause/unpause failure"""
493 def __init__(self, tapdisk):
494 self.tapdisk = tapdisk
496 def __str__(self):
497 return str(self.tapdisk)
500def mkdirs(path, mode=0o777):
501 if not os.path.exists(path):
502 parent, subdir = os.path.split(path)
503 assert parent != path
504 try:
505 if parent:
506 mkdirs(parent, mode)
507 if subdir:
508 os.mkdir(path, mode)
509 except OSError as e:
510 if e.errno != errno.EEXIST:
511 raise
514class KObject(object):
516 SYSFS_CLASSTYPE = None
518 def sysfs_devname(self):
519 raise NotImplementedError("sysfs_devname is undefined")
522class Attribute(object):
524 SYSFS_NODENAME = None
526 def __init__(self, path):
527 self.path = path
529 @classmethod
530 def from_kobject(cls, kobj):
531 path = "%s/%s" % (kobj.sysfs_path(), cls.SYSFS_NODENAME)
532 return cls(path)
534 class NoSuchAttribute(Exception):
535 def __init__(self, name):
536 self.name = name
538 def __str__(self):
539 return "No such attribute: %s" % self.name
541 def _open(self, mode='r'):
542 try:
543 return open(self.path, mode)
544 except IOError as e:
545 if e.errno == errno.ENOENT:
546 raise self.NoSuchAttribute(self)
547 raise
549 def readline(self):
550 f = self._open('r')
551 s = f.readline().rstrip()
552 f.close()
553 return s
555 def writeline(self, val):
556 f = self._open('w')
557 f.write(val)
558 f.close()
561class ClassDevice(KObject):
563 @classmethod
564 def sysfs_class_path(cls):
565 return "/sys/class/%s" % cls.SYSFS_CLASSTYPE
567 def sysfs_path(self):
568 return "%s/%s" % (self.sysfs_class_path(),
569 self.sysfs_devname())
572class Blktap(ClassDevice):
574 DEV_BASEDIR = '/dev/xen/blktap-2'
576 SYSFS_CLASSTYPE = "blktap2"
578 def __init__(self, minor):
579 self.minor = minor
580 self._pool = None
581 self._task = None
583 @classmethod
584 def allocate(cls):
585 # FIXME. Should rather go into init.
586 mkdirs(cls.DEV_BASEDIR)
588 devname = TapCtl.allocate()
589 minor = Tapdisk._parse_minor(devname)
590 return cls(minor)
592 def free(self):
593 TapCtl.free(self.minor)
595 def __str__(self):
596 return "%s(minor=%d)" % (self.__class__.__name__, self.minor)
598 def sysfs_devname(self):
599 return "blktap!blktap%d" % self.minor
601 class Pool(Attribute):
602 SYSFS_NODENAME = "pool"
604 def get_pool_attr(self):
605 if not self._pool:
606 self._pool = self.Pool.from_kobject(self)
607 return self._pool
609 def get_pool_name(self):
610 return self.get_pool_attr().readline()
612 def set_pool_name(self, name):
613 self.get_pool_attr().writeline(name)
615 def set_pool_size(self, pages):
616 self.get_pool().set_size(pages)
618 def get_pool(self):
619 return BlktapControl.get_pool(self.get_pool_name())
621 def set_pool(self, pool):
622 self.set_pool_name(pool.name)
624 class Task(Attribute):
625 SYSFS_NODENAME = "task"
627 def get_task_attr(self):
628 if not self._task:
629 self._task = self.Task.from_kobject(self)
630 return self._task
632 def get_task_pid(self):
633 pid = self.get_task_attr().readline()
634 try:
635 return int(pid)
636 except ValueError:
637 return None
639 def find_tapdisk(self):
640 pid = self.get_task_pid()
641 if pid is None:
642 return None
644 return Tapdisk.find(pid=pid, minor=self.minor)
646 def get_tapdisk(self):
647 tapdisk = self.find_tapdisk()
648 if not tapdisk:
649 raise TapdiskNotRunning(minor=self.minor)
650 return tapdisk
653class Tapdisk(object):
655 TYPES = ['aio', 'vhd']
657 def __init__(self, pid, minor, _type, path, state):
658 self.pid = pid
659 self.minor = minor
660 self.type = _type
661 self.path = path
662 self.state = state
663 self._dirty = False
664 self._blktap = None
666 def __str__(self):
667 state = self.pause_state()
668 return "Tapdisk(%s, pid=%d, minor=%s, state=%s)" % \
669 (self.get_arg(), self.pid, self.minor, state)
671 @classmethod
672 def list(cls, **args):
674 for row in TapCtl.list( ** args):
676 args = {'pid': None,
677 'minor': None,
678 'state': None,
679 '_type': None,
680 'path': None}
682 for key, val in row.items():
683 if key in args:
684 args[key] = val
686 if 'args' in row: 686 ↛ 691line 686 didn't jump to line 691, because the condition on line 686 was never false
687 image = Tapdisk.Arg.parse(row['args'])
688 args['_type'] = image.type
689 args['path'] = image.path
691 if None in args.values(): 691 ↛ 692line 691 didn't jump to line 692, because the condition on line 691 was never true
692 continue
694 yield Tapdisk( ** args)
696 @classmethod
697 def find(cls, **args):
699 found = list(cls.list( ** args))
701 if len(found) > 1: 701 ↛ 702line 701 didn't jump to line 702, because the condition on line 701 was never true
702 raise TapdiskNotUnique(found)
704 if found: 704 ↛ 705line 704 didn't jump to line 705, because the condition on line 704 was never true
705 return found[0]
707 return None
709 @classmethod
710 def find_by_path(cls, path):
711 return cls.find(path=path)
713 @classmethod
714 def find_by_minor(cls, minor):
715 return cls.find(minor=minor)
717 @classmethod
718 def get(cls, **attrs):
720 tapdisk = cls.find( ** attrs)
722 if not tapdisk:
723 raise TapdiskNotRunning( ** attrs)
725 return tapdisk
727 @classmethod
728 def from_path(cls, path):
729 return cls.get(path=path)
731 @classmethod
732 def from_minor(cls, minor):
733 return cls.get(minor=minor)
735 @classmethod
736 def __from_blktap(cls, blktap):
737 tapdisk = cls.from_minor(minor=blktap.minor)
738 tapdisk._blktap = blktap
739 return tapdisk
741 def get_blktap(self):
742 if not self._blktap:
743 self._blktap = Blktap(self.minor)
744 return self._blktap
746 class Arg:
748 def __init__(self, _type, path):
749 self.type = _type
750 self.path = path
752 def __str__(self):
753 return "%s:%s" % (self.type, self.path)
755 @classmethod
756 def parse(cls, arg):
758 try:
759 _type, path = arg.split(":", 1)
760 except ValueError:
761 raise cls.InvalidArgument(arg)
763 if _type not in Tapdisk.TYPES: 763 ↛ 764line 763 didn't jump to line 764, because the condition on line 763 was never true
764 raise cls.InvalidType(_type)
766 return cls(_type, path)
768 class InvalidType(Exception):
769 def __init__(self, _type):
770 self.type = _type
772 def __str__(self):
773 return "Not a Tapdisk type: %s" % self.type
775 class InvalidArgument(Exception):
776 def __init__(self, arg):
777 self.arg = arg
779 def __str__(self):
780 return "Not a Tapdisk image: %s" % self.arg
782 def get_arg(self):
783 return self.Arg(self.type, self.path)
785 def get_devpath(self):
786 return "%s/tapdev%d" % (Blktap.DEV_BASEDIR, self.minor)
788 @classmethod
789 def launch_from_arg(cls, arg):
790 arg = cls.Arg.parse(arg)
791 return cls.launch(arg.path, arg.type, False)
793 @staticmethod
794 def cgclassify(pid):
796 # We dont provide any <controllers>:<path>
797 # so cgclassify uses /etc/cgrules.conf which
798 # we have configured in the spec file.
799 cmd = ["cgclassify", str(pid)]
800 try:
801 util.pread2(cmd)
802 except util.CommandException as e:
803 util.logException(e)
805 @classmethod
806 def launch_on_tap(cls, blktap, path, _type, options):
808 tapdisk = cls.find_by_path(path)
809 if tapdisk: 809 ↛ 810line 809 didn't jump to line 810, because the condition on line 809 was never true
810 raise TapdiskExists(tapdisk)
812 minor = blktap.minor
813 try:
814 pid = TapCtl.spawn()
815 cls.cgclassify(pid)
816 try:
817 TapCtl.attach(pid, minor)
819 try:
820 retry_open = 0
821 while True:
822 try:
823 TapCtl.open(pid, minor, _type, path, options)
824 except TapCtl.CommandFailure as e:
825 err = (
826 'status' in e.info and e.info['status']
827 ) or None
828 if err in (errno.EIO, errno.EROFS, errno.EAGAIN): 828 ↛ 829line 828 didn't jump to line 829, because the condition on line 828 was never true
829 if retry_open < 5:
830 retry_open += 1
831 time.sleep(1)
832 continue
833 if LINSTOR_AVAILABLE and err == errno.EROFS:
834 log_drbd_openers(path)
835 raise
836 try:
837 tapdisk = cls.__from_blktap(blktap)
838 node = '/sys/dev/block/%d:%d' % (tapdisk.major(), tapdisk.minor)
839 util.set_scheduler_sysfs_node(node, ['none', 'noop'])
840 return tapdisk
841 except:
842 TapCtl.close(pid, minor)
843 raise
845 except:
846 TapCtl.detach(pid, minor)
847 raise
849 except:
850 try:
851 TapCtl.shutdown(pid)
852 except:
853 # Best effort to shutdown
854 pass
855 raise
857 except TapCtl.CommandFailure as ctl:
858 util.logException(ctl)
859 if ((path.startswith('/dev/xapi/cd/') or path.startswith('/dev/sr')) and 859 ↛ 863line 859 didn't jump to line 863, because the condition on line 859 was never false
860 ctl.has_status and ctl.get_error_code() == 123): # ENOMEDIUM (No medium found)
861 raise xs_errors.XenError('TapdiskDriveEmpty')
862 else:
863 raise TapdiskFailed(cls.Arg(_type, path), ctl)
865 @classmethod
866 def launch(cls, path, _type, rdonly):
867 blktap = Blktap.allocate()
868 try:
869 return cls.launch_on_tap(blktap, path, _type, {"rdonly": rdonly})
870 except:
871 blktap.free()
872 raise
874 def shutdown(self, force=False):
876 TapCtl.close(self.pid, self.minor, force)
878 TapCtl.detach(self.pid, self.minor)
880 self.get_blktap().free()
882 def pause(self):
884 if not self.is_running():
885 raise TapdiskInvalidState(self)
887 TapCtl.pause(self.pid, self.minor)
889 self._set_dirty()
891 def unpause(self, _type=None, path=None, mirror=None, cbtlog=None):
893 if not self.is_paused():
894 raise TapdiskInvalidState(self)
896 # FIXME: should the arguments be optional?
897 if _type is None:
898 _type = self.type
899 if path is None:
900 path = self.path
902 TapCtl.unpause(self.pid, self.minor, _type, path, mirror=mirror,
903 cbtlog=cbtlog)
905 self._set_dirty()
907 def stats(self):
908 return json.loads(TapCtl.stats(self.pid, self.minor))
909 #
910 # NB. dirty/refresh: reload attributes on next access
911 #
913 def _set_dirty(self):
914 self._dirty = True
916 def _refresh(self, __get):
917 t = self.from_minor(__get('minor'))
918 self.__init__(t.pid, t.minor, t.type, t.path, t.state)
920 def __getattribute__(self, name):
921 def __get(name):
922 # NB. avoid(rec(ursion)
923 return object.__getattribute__(self, name)
925 if __get('_dirty') and \ 925 ↛ 927line 925 didn't jump to line 927, because the condition on line 925 was never true
926 name in ['minor', 'type', 'path', 'state']:
927 self._refresh(__get)
928 self._dirty = False
930 return __get(name)
932 class PauseState:
933 RUNNING = 'R'
934 PAUSING = 'r'
935 PAUSED = 'P'
937 class Flags:
938 DEAD = 0x0001
939 CLOSED = 0x0002
940 QUIESCE_REQUESTED = 0x0004
941 QUIESCED = 0x0008
942 PAUSE_REQUESTED = 0x0010
943 PAUSED = 0x0020
944 SHUTDOWN_REQUESTED = 0x0040
945 LOCKING = 0x0080
946 RETRY_NEEDED = 0x0100
947 LOG_DROPPED = 0x0200
949 PAUSE_MASK = PAUSE_REQUESTED | PAUSED
951 def is_paused(self):
952 return not not (self.state & self.Flags.PAUSED)
954 def is_running(self):
955 return not (self.state & self.Flags.PAUSE_MASK)
957 def pause_state(self):
958 if self.state & self.Flags.PAUSED:
959 return self.PauseState.PAUSED
961 if self.state & self.Flags.PAUSE_REQUESTED:
962 return self.PauseState.PAUSING
964 return self.PauseState.RUNNING
966 @staticmethod
967 def _parse_minor(devpath):
968 regex = r'%s/(blktap|tapdev)(\d+)$' % Blktap.DEV_BASEDIR
969 pattern = re.compile(regex)
970 groups = pattern.search(devpath)
971 if not groups:
972 raise Exception("malformed tap device: '%s' (%s) " % (devpath, regex))
974 minor = groups.group(2)
975 return int(minor)
977 _major = None
979 @classmethod
980 def major(cls):
981 if cls._major:
982 return cls._major
984 devices = open("/proc/devices")
985 for line in devices:
987 row = line.rstrip().split(' ')
988 if len(row) != 2:
989 continue
991 major, name = row
992 if name != 'tapdev':
993 continue
995 cls._major = int(major)
996 break
998 devices.close()
999 return cls._major
1002class VDI(object):
1003 """SR.vdi driver decorator for blktap2"""
1005 CONF_KEY_ALLOW_CACHING = "vdi_allow_caching"
1006 CONF_KEY_MODE_ON_BOOT = "vdi_on_boot"
1007 CONF_KEY_CACHE_SR = "local_cache_sr"
1008 CONF_KEY_O_DIRECT = "o_direct"
1009 LOCK_CACHE_SETUP = "cachesetup"
1011 ATTACH_DETACH_RETRY_SECS = 120
1013 def __init__(self, uuid, target, driver_info):
1014 self.target = self.TargetDriver(target, driver_info)
1015 self._vdi_uuid = uuid
1016 self._session = target.session
1017 self.xenstore_data = scsiutil.update_XS_SCSIdata(uuid, scsiutil.gen_synthetic_page_data(uuid))
1018 self.__o_direct = None
1019 self.__o_direct_reason = None
1020 self.lock = Lock("vdi", uuid)
1021 self.tap = None
1023 def get_o_direct_capability(self, options):
1024 """Returns True/False based on licensing and caching_params"""
1025 if self.__o_direct is not None: 1025 ↛ 1026line 1025 didn't jump to line 1026, because the condition on line 1025 was never true
1026 return self.__o_direct, self.__o_direct_reason
1028 if util.read_caching_is_restricted(self._session): 1028 ↛ 1029line 1028 didn't jump to line 1029, because the condition on line 1028 was never true
1029 self.__o_direct = True
1030 self.__o_direct_reason = "LICENSE_RESTRICTION"
1031 elif not ((self.target.vdi.sr.handles("nfs") or self.target.vdi.sr.handles("ext") or self.target.vdi.sr.handles("smb"))): 1031 ↛ 1034line 1031 didn't jump to line 1034, because the condition on line 1031 was never false
1032 self.__o_direct = True
1033 self.__o_direct_reason = "SR_NOT_SUPPORTED"
1034 elif not (options.get("rdonly") or self.target.vdi.parent):
1035 util.SMlog(self.target.vdi)
1036 self.__o_direct = True
1037 self.__o_direct_reason = "NO_RO_IMAGE"
1038 elif options.get("rdonly") and not self.target.vdi.parent:
1039 self.__o_direct = True
1040 self.__o_direct_reason = "RO_WITH_NO_PARENT"
1041 elif options.get(self.CONF_KEY_O_DIRECT):
1042 self.__o_direct = True
1043 self.__o_direct_reason = "SR_OVERRIDE"
1045 if self.__o_direct is None: 1045 ↛ 1046line 1045 didn't jump to line 1046, because the condition on line 1045 was never true
1046 self.__o_direct = False
1047 self.__o_direct_reason = ""
1049 return self.__o_direct, self.__o_direct_reason
1051 @classmethod
1052 def from_cli(cls, uuid):
1053 import VDI as sm
1055 session = XenAPI.xapi_local()
1056 session.xenapi.login_with_password('root', '', '', 'SM')
1058 target = sm.VDI.from_uuid(session, uuid)
1059 driver_info = target.sr.srcmd.driver_info
1061 session.xenapi.session.logout()
1063 return cls(uuid, target, driver_info)
1065 @staticmethod
1066 def _tap_type(vdi_type):
1067 """Map a VDI type (e.g. 'raw') to a tapdisk driver type (e.g. 'aio')"""
1068 return {
1069 'raw': 'aio',
1070 'vhd': 'vhd',
1071 'iso': 'aio', # for ISO SR
1072 'aio': 'aio', # for LVHD
1073 'file': 'aio',
1074 'phy': 'aio'
1075 }[vdi_type]
1077 def get_tap_type(self):
1078 vdi_type = self.target.get_vdi_type()
1079 return VDI._tap_type(vdi_type)
1081 def get_phy_path(self):
1082 return self.target.get_vdi_path()
1084 class UnexpectedVDIType(Exception):
1086 def __init__(self, vdi_type, target):
1087 self.vdi_type = vdi_type
1088 self.target = target
1090 def __str__(self):
1091 return \
1092 "Target %s has unexpected VDI type '%s'" % \
1093 (type(self.target), self.vdi_type)
1095 VDI_PLUG_TYPE = {'phy': 'phy', # for NETAPP
1096 'raw': 'phy',
1097 'aio': 'tap', # for LVHD raw nodes
1098 'iso': 'tap', # for ISOSR
1099 'file': 'tap',
1100 'vhd': 'tap'}
1102 def tap_wanted(self):
1103 # 1. Let the target vdi_type decide
1105 vdi_type = self.target.get_vdi_type()
1107 try:
1108 plug_type = self.VDI_PLUG_TYPE[vdi_type]
1109 except KeyError:
1110 raise self.UnexpectedVDIType(vdi_type,
1111 self.target.vdi)
1113 if plug_type == 'tap': 1113 ↛ 1114line 1113 didn't jump to line 1114, because the condition on line 1113 was never true
1114 return True
1115 elif self.target.vdi.sr.handles('udev'): 1115 ↛ 1121line 1115 didn't jump to line 1121, because the condition on line 1115 was never false
1116 return True
1117 # 2. Otherwise, there may be more reasons
1118 #
1119 # .. TBD
1121 return False
1123 class TargetDriver:
1124 """Safe target driver access."""
1125 # NB. *Must* test caps for optional calls. Some targets
1126 # actually implement some slots, but do not enable them. Just
1127 # try/except would risk breaking compatibility.
1129 def __init__(self, vdi, driver_info):
1130 self.vdi = vdi
1131 self._caps = driver_info['capabilities']
1133 def has_cap(self, cap):
1134 """Determine if target has given capability"""
1135 return cap in self._caps
1137 def attach(self, sr_uuid, vdi_uuid):
1138 #assert self.has_cap("VDI_ATTACH")
1139 return self.vdi.attach(sr_uuid, vdi_uuid)
1141 def detach(self, sr_uuid, vdi_uuid):
1142 #assert self.has_cap("VDI_DETACH")
1143 self.vdi.detach(sr_uuid, vdi_uuid)
1145 def activate(self, sr_uuid, vdi_uuid):
1146 if self.has_cap("VDI_ACTIVATE"):
1147 return self.vdi.activate(sr_uuid, vdi_uuid)
1149 def deactivate(self, sr_uuid, vdi_uuid):
1150 if self.has_cap("VDI_DEACTIVATE"):
1151 self.vdi.deactivate(sr_uuid, vdi_uuid)
1152 #def resize(self, sr_uuid, vdi_uuid, size):
1153 # return self.vdi.resize(sr_uuid, vdi_uuid, size)
1155 def get_vdi_type(self):
1156 _type = self.vdi.vdi_type
1157 if not _type:
1158 _type = self.vdi.sr.sr_vditype
1159 if not _type:
1160 raise VDI.UnexpectedVDIType(_type, self.vdi)
1161 return _type
1163 def get_vdi_path(self):
1164 return self.vdi.path
1166 class Link(object):
1167 """Relink a node under a common name"""
1168 # NB. We have to provide the device node path during
1169 # VDI.attach, but currently do not allocate the tapdisk minor
1170 # before VDI.activate. Therefore those link steps where we
1171 # relink existing devices under deterministic path names.
1173 BASEDIR = None
1175 def _mklink(self, target):
1176 raise NotImplementedError("_mklink is not defined")
1178 def _equals(self, target):
1179 raise NotImplementedError("_equals is not defined")
1181 def __init__(self, path):
1182 self._path = path
1184 @classmethod
1185 def from_name(cls, name):
1186 path = "%s/%s" % (cls.BASEDIR, name)
1187 return cls(path)
1189 @classmethod
1190 def from_uuid(cls, sr_uuid, vdi_uuid):
1191 name = "%s/%s" % (sr_uuid, vdi_uuid)
1192 return cls.from_name(name)
1194 def path(self):
1195 return self._path
1197 def stat(self):
1198 return os.stat(self.path())
1200 def mklink(self, target):
1202 path = self.path()
1203 util.SMlog("%s -> %s" % (self, target))
1205 mkdirs(os.path.dirname(path))
1206 try:
1207 self._mklink(target)
1208 except OSError as e:
1209 # We do unlink during teardown, but have to stay
1210 # idempotent. However, a *wrong* target should never
1211 # be seen.
1212 if e.errno != errno.EEXIST:
1213 raise
1214 assert self._equals(target), "'%s' not equal to '%s'" % (path, target)
1216 def unlink(self):
1217 try:
1218 os.unlink(self.path())
1219 except OSError as e:
1220 if e.errno != errno.ENOENT:
1221 raise
1223 def __str__(self):
1224 path = self.path()
1225 return "%s(%s)" % (self.__class__.__name__, path)
1227 class SymLink(Link):
1228 """Symlink some file to a common name"""
1230 def readlink(self):
1231 return os.readlink(self.path())
1233 def symlink(self):
1234 return self.path()
1236 def _mklink(self, target):
1237 os.symlink(target, self.path())
1239 def _equals(self, target):
1240 return self.readlink() == target
1242 class DeviceNode(Link):
1243 """Relink a block device node to a common name"""
1245 @classmethod
1246 def _real_stat(cls, target):
1247 """stat() not on @target, but its realpath()"""
1248 _target = os.path.realpath(target)
1249 return os.stat(_target)
1251 @classmethod
1252 def is_block(cls, target):
1253 """Whether @target refers to a block device."""
1254 return S_ISBLK(cls._real_stat(target).st_mode)
1256 def _mklink(self, target):
1258 st = self._real_stat(target)
1259 if not S_ISBLK(st.st_mode):
1260 raise self.NotABlockDevice(target, st)
1262 # set group read for disk group as well as root
1263 os.mknod(self.path(), st.st_mode | stat.S_IRGRP, st.st_rdev)
1264 os.chown(self.path(), st.st_uid, grp.getgrnam("disk").gr_gid)
1266 def _equals(self, target):
1267 target_rdev = self._real_stat(target).st_rdev
1268 return self.stat().st_rdev == target_rdev
1270 def rdev(self):
1271 st = self.stat()
1272 assert S_ISBLK(st.st_mode)
1273 return os.major(st.st_rdev), os.minor(st.st_rdev)
1275 class NotABlockDevice(Exception):
1277 def __init__(self, path, st):
1278 self.path = path
1279 self.st = st
1281 def __str__(self):
1282 return "%s is not a block device: %s" % (self.path, self.st)
1284 class Hybrid(Link):
1286 def __init__(self, path):
1287 VDI.Link.__init__(self, path)
1288 self._devnode = VDI.DeviceNode(path)
1289 self._symlink = VDI.SymLink(path)
1291 def rdev(self):
1292 st = self.stat()
1293 if S_ISBLK(st.st_mode):
1294 return self._devnode.rdev()
1295 raise self._devnode.NotABlockDevice(self.path(), st)
1297 def mklink(self, target):
1298 if self._devnode.is_block(target):
1299 self._obj = self._devnode
1300 else:
1301 self._obj = self._symlink
1302 self._obj.mklink(target)
1304 def _equals(self, target):
1305 return self._obj._equals(target)
1307 class PhyLink(SymLink):
1308 BASEDIR = "/dev/sm/phy"
1309 # NB. Cannot use DeviceNodes, e.g. FileVDIs aren't bdevs.
1311 class NBDLink(SymLink):
1313 BASEDIR = "/run/blktap-control/nbd"
1315 class BackendLink(Hybrid):
1316 BASEDIR = "/dev/sm/backend"
1317 # NB. Could be SymLinks as well, but saving major,minor pairs in
1318 # Links enables neat state capturing when managing Tapdisks. Note
1319 # that we essentially have a tap-ctl list replacement here. For
1320 # now make it a 'Hybrid'. Likely to collapse into a DeviceNode as
1321 # soon as ISOs are tapdisks.
1323 @staticmethod
1324 def _tap_activate(phy_path, vdi_type, sr_uuid, options, pool_size=None):
1326 tapdisk = Tapdisk.find_by_path(phy_path)
1327 if not tapdisk: 1327 ↛ 1328line 1327 didn't jump to line 1328, because the condition on line 1327 was never true
1328 blktap = Blktap.allocate()
1329 blktap.set_pool_name(sr_uuid)
1330 if pool_size:
1331 blktap.set_pool_size(pool_size)
1333 try:
1334 tapdisk = \
1335 Tapdisk.launch_on_tap(blktap,
1336 phy_path,
1337 VDI._tap_type(vdi_type),
1338 options)
1339 except:
1340 blktap.free()
1341 raise
1342 util.SMlog("tap.activate: Launched %s" % tapdisk)
1344 else:
1345 util.SMlog("tap.activate: Found %s" % tapdisk)
1347 return tapdisk.get_devpath(), tapdisk
1349 @staticmethod
1350 def _tap_deactivate(minor):
1352 try:
1353 tapdisk = Tapdisk.from_minor(minor)
1354 except TapdiskNotRunning as e:
1355 util.SMlog("tap.deactivate: Warning, %s" % e)
1356 # NB. Should not be here unless the agent refcount
1357 # broke. Also, a clean shutdown should not have leaked
1358 # the recorded minor.
1359 else:
1360 tapdisk.shutdown()
1361 util.SMlog("tap.deactivate: Shut down %s" % tapdisk)
1363 @classmethod
1364 def tap_pause(cls, session, sr_uuid, vdi_uuid, failfast=False):
1365 """
1366 Pauses the tapdisk.
1368 session: a XAPI session
1369 sr_uuid: the UUID of the SR on which VDI lives
1370 vdi_uuid: the UUID of the VDI to pause
1371 failfast: controls whether the VDI lock should be acquired in a
1372 non-blocking manner
1373 """
1374 util.SMlog("Pause request for %s" % vdi_uuid)
1375 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1376 session.xenapi.VDI.add_to_sm_config(vdi_ref, 'paused', 'true')
1377 sm_config = session.xenapi.VDI.get_sm_config(vdi_ref)
1378 for key in [x for x in sm_config.keys() if x.startswith('host_')]: 1378 ↛ 1379line 1378 didn't jump to line 1379, because the loop on line 1378 never started
1379 host_ref = key[len('host_'):]
1380 util.SMlog("Calling tap-pause on host %s" % host_ref)
1381 if not cls.call_pluginhandler(session, host_ref,
1382 sr_uuid, vdi_uuid, "pause", failfast=failfast):
1383 # Failed to pause node
1384 session.xenapi.VDI.remove_from_sm_config(vdi_ref, 'paused')
1385 return False
1386 return True
1388 @classmethod
1389 def tap_unpause(cls, session, sr_uuid, vdi_uuid, secondary=None,
1390 activate_parents=False):
1391 util.SMlog("Unpause request for %s secondary=%s" % (vdi_uuid, secondary))
1392 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1393 sm_config = session.xenapi.VDI.get_sm_config(vdi_ref)
1394 for key in [x for x in sm_config.keys() if x.startswith('host_')]: 1394 ↛ 1395line 1394 didn't jump to line 1395, because the loop on line 1394 never started
1395 host_ref = key[len('host_'):]
1396 util.SMlog("Calling tap-unpause on host %s" % host_ref)
1397 if not cls.call_pluginhandler(session, host_ref,
1398 sr_uuid, vdi_uuid, "unpause", secondary, activate_parents):
1399 # Failed to unpause node
1400 return False
1401 session.xenapi.VDI.remove_from_sm_config(vdi_ref, 'paused')
1402 return True
1404 @classmethod
1405 def tap_refresh(cls, session, sr_uuid, vdi_uuid, activate_parents=False):
1406 util.SMlog("Refresh request for %s" % vdi_uuid)
1407 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1408 sm_config = session.xenapi.VDI.get_sm_config(vdi_ref)
1409 for key in [x for x in sm_config.keys() if x.startswith('host_')]:
1410 host_ref = key[len('host_'):]
1411 util.SMlog("Calling tap-refresh on host %s" % host_ref)
1412 if not cls.call_pluginhandler(session, host_ref,
1413 sr_uuid, vdi_uuid, "refresh", None,
1414 activate_parents=activate_parents):
1415 # Failed to refresh node
1416 return False
1417 return True
1419 @classmethod
1420 def tap_status(cls, session, vdi_uuid):
1421 """Return True if disk is attached, false if it isn't"""
1422 util.SMlog("Disk status request for %s" % vdi_uuid)
1423 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1424 sm_config = session.xenapi.VDI.get_sm_config(vdi_ref)
1425 for key in [x for x in sm_config.keys() if x.startswith('host_')]: 1425 ↛ 1426line 1425 didn't jump to line 1426, because the loop on line 1425 never started
1426 return True
1427 return False
1429 @classmethod
1430 def call_pluginhandler(cls, session, host_ref, sr_uuid, vdi_uuid, action,
1431 secondary=None, activate_parents=False, failfast=False):
1432 """Optionally, activate the parent LV before unpausing"""
1433 try:
1434 args = {"sr_uuid": sr_uuid, "vdi_uuid": vdi_uuid,
1435 "failfast": str(failfast)}
1436 if secondary:
1437 args["secondary"] = secondary
1438 if activate_parents:
1439 args["activate_parents"] = "true"
1440 ret = session.xenapi.host.call_plugin(
1441 host_ref, PLUGIN_TAP_PAUSE, action,
1442 args)
1443 return ret == "True"
1444 except Exception as e:
1445 util.logException("BLKTAP2:call_pluginhandler %s" % e)
1446 return False
1448 def _add_tag(self, vdi_uuid, writable):
1449 util.SMlog("Adding tag to: %s" % vdi_uuid)
1450 attach_mode = "RO"
1451 if writable: 1451 ↛ 1453line 1451 didn't jump to line 1453, because the condition on line 1451 was never false
1452 attach_mode = "RW"
1453 vdi_ref = self._session.xenapi.VDI.get_by_uuid(vdi_uuid)
1454 host_ref = self._session.xenapi.host.get_by_uuid(util.get_this_host())
1455 sm_config = self._session.xenapi.VDI.get_sm_config(vdi_ref)
1456 attached_as = util.attached_as(sm_config)
1457 if NO_MULTIPLE_ATTACH and (attached_as == "RW" or \ 1457 ↛ 1459line 1457 didn't jump to line 1459, because the condition on line 1457 was never true
1458 (attached_as == "RO" and attach_mode == "RW")):
1459 util.SMlog("need to reset VDI %s" % vdi_uuid)
1460 if not resetvdis.reset_vdi(self._session, vdi_uuid, force=False,
1461 term_output=False, writable=writable):
1462 raise util.SMException("VDI %s not detached cleanly" % vdi_uuid)
1463 sm_config = self._session.xenapi.VDI.get_sm_config(vdi_ref)
1464 if 'relinking' in sm_config:
1465 util.SMlog("Relinking key found, back-off and retry" % sm_config)
1466 return False
1467 if 'paused' in sm_config:
1468 util.SMlog("Paused or host_ref key found [%s]" % sm_config)
1469 return False
1470 self._session.xenapi.VDI.add_to_sm_config(
1471 vdi_ref, 'activating', 'True')
1472 host_key = "host_%s" % host_ref
1473 assert host_key not in sm_config
1474 self._session.xenapi.VDI.add_to_sm_config(vdi_ref, host_key,
1475 attach_mode)
1476 sm_config = self._session.xenapi.VDI.get_sm_config(vdi_ref)
1477 if 'paused' in sm_config or 'relinking' in sm_config:
1478 util.SMlog("Found %s key, aborting" % (
1479 'paused' if 'paused' in sm_config else 'relinking'))
1480 self._session.xenapi.VDI.remove_from_sm_config(vdi_ref, host_key)
1481 self._session.xenapi.VDI.remove_from_sm_config(
1482 vdi_ref, 'activating')
1483 return False
1484 util.SMlog("Activate lock succeeded")
1485 return True
1487 def _check_tag(self, vdi_uuid):
1488 vdi_ref = self._session.xenapi.VDI.get_by_uuid(vdi_uuid)
1489 sm_config = self._session.xenapi.VDI.get_sm_config(vdi_ref)
1490 if 'paused' in sm_config:
1491 util.SMlog("Paused key found [%s]" % sm_config)
1492 return False
1493 return True
1495 def _remove_tag(self, vdi_uuid):
1496 vdi_ref = self._session.xenapi.VDI.get_by_uuid(vdi_uuid)
1497 host_ref = self._session.xenapi.host.get_by_uuid(util.get_this_host())
1498 sm_config = self._session.xenapi.VDI.get_sm_config(vdi_ref)
1499 host_key = "host_%s" % host_ref
1500 if host_key in sm_config:
1501 self._session.xenapi.VDI.remove_from_sm_config(vdi_ref, host_key)
1502 util.SMlog("Removed host key %s for %s" % (host_key, vdi_uuid))
1503 else:
1504 util.SMlog("_remove_tag: host key %s not found, ignore" % host_key)
1506 def _get_pool_config(self, pool_name):
1507 pool_info = dict()
1508 vdi_ref = self.target.vdi.sr.srcmd.params.get('vdi_ref')
1509 if not vdi_ref: 1509 ↛ 1512line 1509 didn't jump to line 1512, because the condition on line 1509 was never true
1510 # attach_from_config context: HA disks don't need to be in any
1511 # special pool
1512 return pool_info
1514 sr_ref = self.target.vdi.sr.srcmd.params.get('sr_ref')
1515 sr_config = self._session.xenapi.SR.get_other_config(sr_ref)
1516 vdi_config = self._session.xenapi.VDI.get_other_config(vdi_ref)
1517 pool_size_str = sr_config.get(POOL_SIZE_KEY)
1518 pool_name_override = vdi_config.get(POOL_NAME_KEY)
1519 if pool_name_override: 1519 ↛ 1524line 1519 didn't jump to line 1524, because the condition on line 1519 was never false
1520 pool_name = pool_name_override
1521 pool_size_override = vdi_config.get(POOL_SIZE_KEY)
1522 if pool_size_override: 1522 ↛ 1524line 1522 didn't jump to line 1524, because the condition on line 1522 was never false
1523 pool_size_str = pool_size_override
1524 pool_size = 0
1525 if pool_size_str: 1525 ↛ 1535line 1525 didn't jump to line 1535, because the condition on line 1525 was never false
1526 try:
1527 pool_size = int(pool_size_str)
1528 if pool_size < 1 or pool_size > MAX_FULL_RINGS: 1528 ↛ 1529line 1528 didn't jump to line 1529, because the condition on line 1528 was never true
1529 raise ValueError("outside of range")
1530 pool_size = NUM_PAGES_PER_RING * pool_size
1531 except ValueError:
1532 util.SMlog("Error: invalid mem-pool-size %s" % pool_size_str)
1533 pool_size = 0
1535 pool_info["mem-pool"] = pool_name
1536 if pool_size: 1536 ↛ 1539line 1536 didn't jump to line 1539, because the condition on line 1536 was never false
1537 pool_info["mem-pool-size"] = str(pool_size)
1539 return pool_info
1541 def linkNBD(self, sr_uuid, vdi_uuid):
1542 if self.tap:
1543 nbd_path = '/run/blktap-control/nbd%d.%d' % (int(self.tap.pid),
1544 int(self.tap.minor))
1545 VDI.NBDLink.from_uuid(sr_uuid, vdi_uuid).mklink(nbd_path)
1547 def attach(self, sr_uuid, vdi_uuid, writable, activate=False, caching_params={}):
1548 """Return/dev/sm/backend symlink path"""
1549 self.xenstore_data.update(self._get_pool_config(sr_uuid))
1550 if not self.target.has_cap("ATOMIC_PAUSE") or activate:
1551 util.SMlog("Attach & activate")
1552 self._attach(sr_uuid, vdi_uuid)
1553 dev_path = self._activate(sr_uuid, vdi_uuid,
1554 {"rdonly": not writable})
1555 self.BackendLink.from_uuid(sr_uuid, vdi_uuid).mklink(dev_path)
1556 self.linkNBD(sr_uuid, vdi_uuid)
1558 # Return backend/ link
1559 back_path = self.BackendLink.from_uuid(sr_uuid, vdi_uuid).path()
1560 if self.tap_wanted():
1561 # Only have NBD if we also have a tap
1562 nbd_path = "nbd:unix:{}:exportname={}".format(
1563 VDI.NBDLink.from_uuid(sr_uuid, vdi_uuid).path(),
1564 vdi_uuid)
1565 else:
1566 nbd_path = ""
1568 options = {"rdonly": not writable}
1569 options.update(caching_params)
1570 o_direct, o_direct_reason = self.get_o_direct_capability(options)
1571 struct = {'params': back_path,
1572 'params_nbd': nbd_path,
1573 'o_direct': o_direct,
1574 'o_direct_reason': o_direct_reason,
1575 'xenstore_data': self.xenstore_data}
1576 util.SMlog('result: %s' % struct)
1578 try:
1579 f = open("%s.attach_info" % back_path, 'a')
1580 f.write(xmlrpc.client.dumps((struct, ), "", True))
1581 f.close()
1582 except:
1583 pass
1585 return xmlrpc.client.dumps((struct, ), "", True)
1587 def activate(self, sr_uuid, vdi_uuid, writable, caching_params):
1588 util.SMlog("blktap2.activate")
1589 options = {"rdonly": not writable}
1590 options.update(caching_params)
1592 sr_ref = self.target.vdi.sr.srcmd.params.get('sr_ref')
1593 sr_other_config = self._session.xenapi.SR.get_other_config(sr_ref)
1594 for i in range(self.ATTACH_DETACH_RETRY_SECS): 1594 ↛ 1601line 1594 didn't jump to line 1601, because the loop on line 1594 didn't complete
1595 try:
1596 if self._activate_locked(sr_uuid, vdi_uuid, options):
1597 return
1598 except util.SRBusyException:
1599 util.SMlog("SR locked, retrying")
1600 time.sleep(1)
1601 raise util.SMException("VDI %s locked" % vdi_uuid)
1603 @locking("VDIUnavailable")
1604 def _activate_locked(self, sr_uuid, vdi_uuid, options):
1605 """Wraps target.activate and adds a tapdisk"""
1607 #util.SMlog("VDI.activate %s" % vdi_uuid)
1608 refresh = False
1609 if self.tap_wanted(): 1609 ↛ 1614line 1609 didn't jump to line 1614, because the condition on line 1609 was never false
1610 if not self._add_tag(vdi_uuid, not options["rdonly"]):
1611 return False
1612 refresh = True
1614 try:
1615 if refresh: 1615 ↛ 1626line 1615 didn't jump to line 1626, because the condition on line 1615 was never false
1616 # it is possible that while the VDI was paused some of its
1617 # attributes have changed (e.g. its size if it was inflated; or its
1618 # path if it was leaf-coalesced onto a raw LV), so refresh the
1619 # object completely
1620 params = self.target.vdi.sr.srcmd.params
1621 target = sm.VDI.from_uuid(self.target.vdi.session, vdi_uuid)
1622 target.sr.srcmd.params = params
1623 driver_info = target.sr.srcmd.driver_info
1624 self.target = self.TargetDriver(target, driver_info)
1626 util.fistpoint.activate_custom_fn( 1626 ↛ exitline 1626 didn't jump to the function exit
1627 "blktap_activate_inject_failure",
1628 lambda: util.inject_failure())
1630 # Attach the physical node
1631 if self.target.has_cap("ATOMIC_PAUSE"): 1631 ↛ 1634line 1631 didn't jump to line 1634, because the condition on line 1631 was never false
1632 self._attach(sr_uuid, vdi_uuid)
1634 vdi_type = self.target.get_vdi_type()
1636 # Take lvchange-p Lock before running
1637 # tap-ctl open
1638 # Needed to avoid race with lvchange -p which is
1639 # now taking the same lock
1640 # This is a fix for CA-155766
1641 if hasattr(self.target.vdi.sr, 'DRIVER_TYPE') and \ 1641 ↛ 1644line 1641 didn't jump to line 1644, because the condition on line 1641 was never true
1642 self.target.vdi.sr.DRIVER_TYPE == 'lvhd' and \
1643 vdi_type == vhdutil.VDI_TYPE_VHD:
1644 lock = Lock("lvchange-p", lvhdutil.NS_PREFIX_LVM + sr_uuid)
1645 lock.acquire()
1647 # When we attach a static VDI for HA, we cannot communicate with
1648 # xapi, because has not started yet. These VDIs are raw.
1649 if vdi_type != vhdutil.VDI_TYPE_RAW: 1649 ↛ 1660line 1649 didn't jump to line 1660, because the condition on line 1649 was never false
1650 session = self.target.vdi.session
1651 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1652 # pylint: disable=used-before-assignment
1653 sm_config = session.xenapi.VDI.get_sm_config(vdi_ref)
1654 if 'key_hash' in sm_config: 1654 ↛ 1655line 1654 didn't jump to line 1655, because the condition on line 1654 was never true
1655 key_hash = sm_config['key_hash']
1656 options['key_hash'] = key_hash
1657 options['vdi_uuid'] = vdi_uuid
1658 util.SMlog('Using key with hash {} for VDI {}'.format(key_hash, vdi_uuid))
1659 # Activate the physical node
1660 dev_path = self._activate(sr_uuid, vdi_uuid, options)
1662 if hasattr(self.target.vdi.sr, 'DRIVER_TYPE') and \ 1662 ↛ 1665line 1662 didn't jump to line 1665, because the condition on line 1662 was never true
1663 self.target.vdi.sr.DRIVER_TYPE == 'lvhd' and \
1664 self.target.get_vdi_type() == vhdutil.VDI_TYPE_VHD:
1665 lock.release()
1666 except:
1667 util.SMlog("Exception in activate/attach")
1668 if self.tap_wanted():
1669 util.fistpoint.activate_custom_fn(
1670 "blktap_activate_error_handling",
1671 lambda: time.sleep(30))
1672 while True:
1673 try:
1674 self._remove_tag(vdi_uuid)
1675 break
1676 except xmlrpc.client.ProtocolError as e:
1677 # If there's a connection error, keep trying forever.
1678 if e.errcode == http.HTTPStatus.INTERNAL_SERVER_ERROR.value:
1679 continue
1680 else:
1681 util.SMlog('failed to remove tag: %s' % e)
1682 break
1683 except Exception as e:
1684 util.SMlog('failed to remove tag: %s' % e)
1685 break
1686 raise
1687 finally:
1688 vdi_ref = self._session.xenapi.VDI.get_by_uuid(vdi_uuid)
1689 self._session.xenapi.VDI.remove_from_sm_config(
1690 vdi_ref, 'activating')
1691 util.SMlog("Removed activating flag from %s" % vdi_uuid) 1691 ↛ exitline 1691 didn't except from function '_activate_locked', because the raise on line 1686 wasn't executed
1693 # Link result to backend/
1694 self.BackendLink.from_uuid(sr_uuid, vdi_uuid).mklink(dev_path)
1695 self.linkNBD(sr_uuid, vdi_uuid)
1696 return True
1698 def _activate(self, sr_uuid, vdi_uuid, options):
1699 vdi_options = self.target.activate(sr_uuid, vdi_uuid)
1701 dev_path = self.setup_cache(sr_uuid, vdi_uuid, options)
1702 if not dev_path: 1702 ↛ 1716line 1702 didn't jump to line 1716, because the condition on line 1702 was never false
1703 phy_path = self.PhyLink.from_uuid(sr_uuid, vdi_uuid).readlink()
1704 # Maybe launch a tapdisk on the physical link
1705 if self.tap_wanted(): 1705 ↛ 1714line 1705 didn't jump to line 1714, because the condition on line 1705 was never false
1706 vdi_type = self.target.get_vdi_type()
1707 options["o_direct"] = self.get_o_direct_capability(options)[0]
1708 if vdi_options: 1708 ↛ 1710line 1708 didn't jump to line 1710, because the condition on line 1708 was never false
1709 options.update(vdi_options)
1710 dev_path, self.tap = self._tap_activate(phy_path, vdi_type,
1711 sr_uuid, options,
1712 self._get_pool_config(sr_uuid).get("mem-pool-size"))
1713 else:
1714 dev_path = phy_path # Just reuse phy
1716 return dev_path
1718 def _attach(self, sr_uuid, vdi_uuid):
1719 attach_info = xmlrpc.client.loads(self.target.attach(sr_uuid, vdi_uuid))[0][0]
1720 params = attach_info['params']
1721 xenstore_data = attach_info['xenstore_data']
1722 phy_path = util.to_plain_string(params)
1723 self.xenstore_data.update(xenstore_data)
1724 # Save it to phy/
1725 self.PhyLink.from_uuid(sr_uuid, vdi_uuid).mklink(phy_path)
1727 def deactivate(self, sr_uuid, vdi_uuid, caching_params):
1728 util.SMlog("blktap2.deactivate")
1729 for i in range(self.ATTACH_DETACH_RETRY_SECS):
1730 try:
1731 if self._deactivate_locked(sr_uuid, vdi_uuid, caching_params):
1732 return
1733 except util.SRBusyException as e:
1734 util.SMlog("SR locked, retrying")
1735 time.sleep(1)
1736 raise util.SMException("VDI %s locked" % vdi_uuid)
1738 @locking("VDIUnavailable")
1739 def _deactivate_locked(self, sr_uuid, vdi_uuid, caching_params):
1740 """Wraps target.deactivate and removes a tapdisk"""
1742 #util.SMlog("VDI.deactivate %s" % vdi_uuid)
1743 if self.tap_wanted() and not self._check_tag(vdi_uuid):
1744 return False
1746 self._deactivate(sr_uuid, vdi_uuid, caching_params)
1747 if self.target.has_cap("ATOMIC_PAUSE"):
1748 self._detach(sr_uuid, vdi_uuid)
1749 if self.tap_wanted():
1750 self._remove_tag(vdi_uuid)
1752 return True
1754 def _resetPhylink(self, sr_uuid, vdi_uuid, path):
1755 self.PhyLink.from_uuid(sr_uuid, vdi_uuid).mklink(path)
1757 def detach(self, sr_uuid, vdi_uuid, deactivate=False, caching_params={}):
1758 if not self.target.has_cap("ATOMIC_PAUSE") or deactivate:
1759 util.SMlog("Deactivate & detach")
1760 self._deactivate(sr_uuid, vdi_uuid, caching_params)
1761 self._detach(sr_uuid, vdi_uuid)
1762 else:
1763 pass # nothing to do
1765 def _deactivate(self, sr_uuid, vdi_uuid, caching_params):
1766 import VDI as sm
1768 # Shutdown tapdisk
1769 back_link = self.BackendLink.from_uuid(sr_uuid, vdi_uuid)
1771 if not util.pathexists(back_link.path()):
1772 util.SMlog("Backend path %s does not exist" % back_link.path())
1773 return
1775 try:
1776 attach_info_path = "%s.attach_info" % (back_link.path())
1777 os.unlink(attach_info_path)
1778 except:
1779 util.SMlog("unlink of attach_info failed")
1781 try:
1782 major, minor = back_link.rdev()
1783 except self.DeviceNode.NotABlockDevice:
1784 pass
1785 else:
1786 if major == Tapdisk.major():
1787 self._tap_deactivate(minor)
1788 self.remove_cache(sr_uuid, vdi_uuid, caching_params)
1790 # Remove the backend link
1791 back_link.unlink()
1792 VDI.NBDLink.from_uuid(sr_uuid, vdi_uuid).unlink()
1794 # Deactivate & detach the physical node
1795 if self.tap_wanted() and self.target.vdi.session is not None:
1796 # it is possible that while the VDI was paused some of its
1797 # attributes have changed (e.g. its size if it was inflated; or its
1798 # path if it was leaf-coalesced onto a raw LV), so refresh the
1799 # object completely
1800 target = sm.VDI.from_uuid(self.target.vdi.session, vdi_uuid)
1801 driver_info = target.sr.srcmd.driver_info
1802 self.target = self.TargetDriver(target, driver_info)
1804 self.target.deactivate(sr_uuid, vdi_uuid)
1806 def _detach(self, sr_uuid, vdi_uuid):
1807 self.target.detach(sr_uuid, vdi_uuid)
1809 # Remove phy/
1810 self.PhyLink.from_uuid(sr_uuid, vdi_uuid).unlink()
1812 def _updateCacheRecord(self, session, vdi_uuid, on_boot, caching):
1813 # Remove existing VDI.sm_config fields
1814 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1815 for key in ["on_boot", "caching"]:
1816 session.xenapi.VDI.remove_from_sm_config(vdi_ref, key)
1817 if not on_boot is None:
1818 session.xenapi.VDI.add_to_sm_config(vdi_ref, 'on_boot', on_boot)
1819 if not caching is None:
1820 session.xenapi.VDI.add_to_sm_config(vdi_ref, 'caching', caching)
1822 def setup_cache(self, sr_uuid, vdi_uuid, params):
1823 if params.get(self.CONF_KEY_ALLOW_CACHING) != "true": 1823 ↛ 1826line 1823 didn't jump to line 1826, because the condition on line 1823 was never false
1824 return
1826 util.SMlog("Requested local caching")
1827 if not self.target.has_cap("SR_CACHING"):
1828 util.SMlog("Error: local caching not supported by this SR")
1829 return
1831 scratch_mode = False
1832 if params.get(self.CONF_KEY_MODE_ON_BOOT) == "reset":
1833 scratch_mode = True
1834 util.SMlog("Requested scratch mode")
1835 if not self.target.has_cap("VDI_RESET_ON_BOOT/2"):
1836 util.SMlog("Error: scratch mode not supported by this SR")
1837 return
1839 dev_path = None
1840 local_sr_uuid = params.get(self.CONF_KEY_CACHE_SR)
1841 if not local_sr_uuid:
1842 util.SMlog("ERROR: Local cache SR not specified, not enabling")
1843 return
1844 dev_path = self._setup_cache(self._session, sr_uuid, vdi_uuid,
1845 local_sr_uuid, scratch_mode, params)
1847 if dev_path:
1848 self._updateCacheRecord(self._session, self.target.vdi.uuid,
1849 params.get(self.CONF_KEY_MODE_ON_BOOT),
1850 params.get(self.CONF_KEY_ALLOW_CACHING))
1852 return dev_path
1854 def alert_no_cache(self, session, vdi_uuid, cache_sr_uuid, err):
1855 vm_uuid = None
1856 vm_label = ""
1857 try:
1858 cache_sr_ref = session.xenapi.SR.get_by_uuid(cache_sr_uuid)
1859 cache_sr_rec = session.xenapi.SR.get_record(cache_sr_ref)
1860 cache_sr_label = cache_sr_rec.get("name_label")
1862 host_ref = session.xenapi.host.get_by_uuid(util.get_this_host())
1863 host_rec = session.xenapi.host.get_record(host_ref)
1864 host_label = host_rec.get("name_label")
1866 vdi_ref = session.xenapi.VDI.get_by_uuid(vdi_uuid)
1867 vbds = session.xenapi.VBD.get_all_records_where( \
1868 "field \"VDI\" = \"%s\"" % vdi_ref)
1869 for vbd_rec in vbds.values():
1870 vm_ref = vbd_rec.get("VM")
1871 vm_rec = session.xenapi.VM.get_record(vm_ref)
1872 vm_uuid = vm_rec.get("uuid")
1873 vm_label = vm_rec.get("name_label")
1874 except:
1875 util.logException("alert_no_cache")
1877 alert_obj = "SR"
1878 alert_uuid = str(cache_sr_uuid)
1879 alert_str = "No space left in Local Cache SR %s" % cache_sr_uuid
1880 if vm_uuid:
1881 alert_obj = "VM"
1882 alert_uuid = vm_uuid
1883 reason = ""
1884 if err == errno.ENOSPC:
1885 reason = "because there is no space left"
1886 alert_str = "The VM \"%s\" is not using IntelliCache %s on the Local Cache SR (\"%s\") on host \"%s\"" % \
1887 (vm_label, reason, cache_sr_label, host_label)
1889 util.SMlog("Creating alert: (%s, %s, \"%s\")" % \
1890 (alert_obj, alert_uuid, alert_str))
1891 session.xenapi.message.create("No space left in local cache", "3",
1892 alert_obj, alert_uuid, alert_str)
1894 def _setup_cache(self, session, sr_uuid, vdi_uuid, local_sr_uuid,
1895 scratch_mode, options):
1896 import SR
1897 import EXTSR
1898 import NFSSR
1899 from lock import Lock
1900 from FileSR import FileVDI
1902 parent_uuid = vhdutil.getParent(self.target.vdi.path,
1903 FileVDI.extractUuid)
1904 if not parent_uuid:
1905 util.SMlog("ERROR: VDI %s has no parent, not enabling" % \
1906 self.target.vdi.uuid)
1907 return
1909 util.SMlog("Setting up cache")
1910 parent_uuid = parent_uuid.strip()
1911 shared_target = NFSSR.NFSFileVDI(self.target.vdi.sr, parent_uuid)
1913 if shared_target.parent:
1914 util.SMlog("ERROR: Parent VDI %s has parent, not enabling" %
1915 shared_target.uuid)
1916 return
1918 SR.registerSR(EXTSR.EXTSR)
1919 local_sr = SR.SR.from_uuid(session, local_sr_uuid)
1921 lock = Lock(self.LOCK_CACHE_SETUP, parent_uuid)
1922 lock.acquire()
1924 # read cache
1925 read_cache_path = "%s/%s.vhdcache" % (local_sr.path, shared_target.uuid)
1926 if util.pathexists(read_cache_path):
1927 util.SMlog("Read cache node (%s) already exists, not creating" % \
1928 read_cache_path)
1929 else:
1930 try:
1931 vhdutil.snapshot(read_cache_path, shared_target.path, False)
1932 except util.CommandException as e:
1933 util.SMlog("Error creating parent cache: %s" % e)
1934 self.alert_no_cache(session, vdi_uuid, local_sr_uuid, e.code)
1935 return None
1937 # local write node
1938 leaf_size = vhdutil.getSizeVirt(self.target.vdi.path)
1939 local_leaf_path = "%s/%s.vhdcache" % \
1940 (local_sr.path, self.target.vdi.uuid)
1941 if util.pathexists(local_leaf_path):
1942 util.SMlog("Local leaf node (%s) already exists, deleting" % \
1943 local_leaf_path)
1944 os.unlink(local_leaf_path)
1945 try:
1946 vhdutil.snapshot(local_leaf_path, read_cache_path, False,
1947 msize=leaf_size // 1024 // 1024, checkEmpty=False)
1948 except util.CommandException as e:
1949 util.SMlog("Error creating leaf cache: %s" % e)
1950 self.alert_no_cache(session, vdi_uuid, local_sr_uuid, e.code)
1951 return None
1953 local_leaf_size = vhdutil.getSizeVirt(local_leaf_path)
1954 if leaf_size > local_leaf_size:
1955 util.SMlog("Leaf size %d > local leaf cache size %d, resizing" %
1956 (leaf_size, local_leaf_size))
1957 vhdutil.setSizeVirtFast(local_leaf_path, leaf_size)
1959 vdi_type = self.target.get_vdi_type()
1961 prt_tapdisk = Tapdisk.find_by_path(read_cache_path)
1962 if not prt_tapdisk:
1963 parent_options = copy.deepcopy(options)
1964 parent_options["rdonly"] = False
1965 parent_options["lcache"] = True
1967 blktap = Blktap.allocate()
1968 try:
1969 blktap.set_pool_name("lcache-parent-pool-%s" % blktap.minor)
1970 # no need to change pool_size since each parent tapdisk is in
1971 # its own pool
1972 prt_tapdisk = \
1973 Tapdisk.launch_on_tap(blktap, read_cache_path,
1974 'vhd', parent_options)
1975 except:
1976 blktap.free()
1977 raise
1979 secondary = "%s:%s" % (self.target.get_vdi_type(),
1980 self.PhyLink.from_uuid(sr_uuid, vdi_uuid).readlink())
1982 util.SMlog("Parent tapdisk: %s" % prt_tapdisk)
1983 leaf_tapdisk = Tapdisk.find_by_path(local_leaf_path)
1984 if not leaf_tapdisk:
1985 blktap = Blktap.allocate()
1986 child_options = copy.deepcopy(options)
1987 child_options["rdonly"] = False
1988 child_options["lcache"] = False
1989 child_options["existing_prt"] = prt_tapdisk.minor
1990 child_options["secondary"] = secondary
1991 child_options["standby"] = scratch_mode
1992 try:
1993 leaf_tapdisk = \
1994 Tapdisk.launch_on_tap(blktap, local_leaf_path,
1995 'vhd', child_options)
1996 except:
1997 blktap.free()
1998 raise
2000 lock.release()
2002 util.SMlog("Local read cache: %s, local leaf: %s" % \
2003 (read_cache_path, local_leaf_path))
2005 self.tap = leaf_tapdisk
2006 return leaf_tapdisk.get_devpath()
2008 def remove_cache(self, sr_uuid, vdi_uuid, params):
2009 if not self.target.has_cap("SR_CACHING"):
2010 return
2012 caching = params.get(self.CONF_KEY_ALLOW_CACHING) == "true"
2014 local_sr_uuid = params.get(self.CONF_KEY_CACHE_SR)
2015 if caching and not local_sr_uuid:
2016 util.SMlog("ERROR: Local cache SR not specified, ignore")
2017 return
2019 if caching:
2020 self._remove_cache(self._session, local_sr_uuid)
2022 if self._session is not None:
2023 self._updateCacheRecord(self._session, self.target.vdi.uuid, None, None)
2025 def _is_tapdisk_in_use(self, minor):
2026 retVal, links, sockets = util.findRunningProcessOrOpenFile("tapdisk")
2027 if not retVal:
2028 # err on the side of caution
2029 return True
2031 for link in links:
2032 if link.find("tapdev%d" % minor) != -1:
2033 return True
2035 socket_re = re.compile(r'^/.*/nbd\d+\.%d' % minor)
2036 for s in sockets:
2037 if socket_re.match(s):
2038 return True
2040 return False
2042 def _remove_cache(self, session, local_sr_uuid):
2043 import SR
2044 import EXTSR
2045 import NFSSR
2046 from lock import Lock
2047 from FileSR import FileVDI
2049 parent_uuid = vhdutil.getParent(self.target.vdi.path,
2050 FileVDI.extractUuid)
2051 if not parent_uuid:
2052 util.SMlog("ERROR: No parent for VDI %s, ignore" % \
2053 self.target.vdi.uuid)
2054 return
2056 util.SMlog("Tearing down the cache")
2058 parent_uuid = parent_uuid.strip()
2059 shared_target = NFSSR.NFSFileVDI(self.target.vdi.sr, parent_uuid)
2061 SR.registerSR(EXTSR.EXTSR)
2062 local_sr = SR.SR.from_uuid(session, local_sr_uuid)
2064 lock = Lock(self.LOCK_CACHE_SETUP, parent_uuid)
2065 lock.acquire()
2067 # local write node
2068 local_leaf_path = "%s/%s.vhdcache" % \
2069 (local_sr.path, self.target.vdi.uuid)
2070 if util.pathexists(local_leaf_path):
2071 util.SMlog("Deleting local leaf node %s" % local_leaf_path)
2072 os.unlink(local_leaf_path)
2074 read_cache_path = "%s/%s.vhdcache" % (local_sr.path, shared_target.uuid)
2075 prt_tapdisk = Tapdisk.find_by_path(read_cache_path)
2076 if not prt_tapdisk:
2077 util.SMlog("Parent tapdisk not found")
2078 elif not self._is_tapdisk_in_use(prt_tapdisk.minor):
2079 util.SMlog("Parent tapdisk not in use: shutting down %s" % \
2080 read_cache_path)
2081 try:
2082 prt_tapdisk.shutdown()
2083 except:
2084 util.logException("shutting down parent tapdisk")
2085 else:
2086 util.SMlog("Parent tapdisk still in use: %s" % read_cache_path)
2087 # the parent cache files are removed during the local SR's background
2088 # GC run
2090 lock.release()
2092PythonKeyError = KeyError
2095class UEventHandler(object):
2097 def __init__(self):
2098 self._action = None
2100 class KeyError(PythonKeyError):
2101 def __init__(self, args):
2102 super().__init__(args)
2103 self.key = args[0]
2105 def __str__(self):
2106 return \
2107 "Key '%s' missing in environment. " % self.key + \
2108 "Not called in udev context?"
2110 @classmethod
2111 def getenv(cls, key):
2112 try:
2113 return os.environ[key]
2114 except KeyError as e:
2115 raise cls.KeyError(e.args[0])
2117 def get_action(self):
2118 if not self._action:
2119 self._action = self.getenv('ACTION')
2120 return self._action
2122 class UnhandledEvent(Exception):
2124 def __init__(self, event, handler):
2125 self.event = event
2126 self.handler = handler
2128 def __str__(self):
2129 return "Uevent '%s' not handled by %s" % \
2130 (self.event, self.handler.__class__.__name__)
2132 ACTIONS = {}
2134 def run(self):
2136 action = self.get_action()
2137 try:
2138 fn = self.ACTIONS[action]
2139 except KeyError:
2140 raise self.UnhandledEvent(action, self)
2142 return fn(self)
2144 def __str__(self):
2145 try:
2146 action = self.get_action()
2147 except:
2148 action = None
2149 return "%s[%s]" % (self.__class__.__name__, action)
2152class __BlktapControl(ClassDevice):
2153 SYSFS_CLASSTYPE = "misc"
2155 def __init__(self):
2156 ClassDevice.__init__(self)
2157 self._default_pool = None
2159 def sysfs_devname(self):
2160 return "blktap!control"
2162 class DefaultPool(Attribute):
2163 SYSFS_NODENAME = "default_pool"
2165 def get_default_pool_attr(self):
2166 if not self._default_pool:
2167 self._default_pool = self.DefaultPool.from_kobject(self)
2168 return self._default_pool
2170 def get_default_pool_name(self):
2171 return self.get_default_pool_attr().readline()
2173 def set_default_pool_name(self, name):
2174 self.get_default_pool_attr().writeline(name)
2176 def get_default_pool(self):
2177 return BlktapControl.get_pool(self.get_default_pool_name())
2179 def set_default_pool(self, pool):
2180 self.set_default_pool_name(pool.name)
2182 class NoSuchPool(Exception):
2183 def __init__(self, name):
2184 self.name = name
2186 def __str__(self):
2187 return "No such pool: {}".format(self.name)
2189 def get_pool(self, name):
2190 path = "%s/pools/%s" % (self.sysfs_path(), name)
2192 if not os.path.isdir(path):
2193 raise self.NoSuchPool(name)
2195 return PagePool(path)
2197BlktapControl = __BlktapControl()
2200class PagePool(KObject):
2202 def __init__(self, path):
2203 self.path = path
2204 self._size = None
2206 def sysfs_path(self):
2207 return self.path
2209 class Size(Attribute):
2210 SYSFS_NODENAME = "size"
2212 def get_size_attr(self):
2213 if not self._size:
2214 self._size = self.Size.from_kobject(self)
2215 return self._size
2217 def set_size(self, pages):
2218 pages = str(pages)
2219 self.get_size_attr().writeline(pages)
2221 def get_size(self):
2222 pages = self.get_size_attr().readline()
2223 return int(pages)
2226class BusDevice(KObject):
2228 SYSFS_BUSTYPE = None
2230 @classmethod
2231 def sysfs_bus_path(cls):
2232 return "/sys/bus/%s" % cls.SYSFS_BUSTYPE
2234 def sysfs_path(self):
2235 path = "%s/devices/%s" % (self.sysfs_bus_path(),
2236 self.sysfs_devname())
2238 return path
2241class XenbusDevice(BusDevice):
2242 """Xenbus device, in XS and sysfs"""
2244 XBT_NIL = ""
2246 XENBUS_DEVTYPE = None
2248 def __init__(self, domid, devid):
2249 self.domid = int(domid)
2250 self.devid = int(devid)
2251 self._xbt = XenbusDevice.XBT_NIL
2253 import xen.lowlevel.xs # pylint: disable=import-error
2254 self.xs = xen.lowlevel.xs.xs()
2256 def xs_path(self, key=None):
2257 path = "backend/%s/%d/%d" % (self.XENBUS_DEVTYPE,
2258 self.domid,
2259 self.devid)
2260 if key is not None:
2261 path = "%s/%s" % (path, key)
2263 return path
2265 def _log(self, prio, msg):
2266 syslog(prio, msg)
2268 def info(self, msg):
2269 self._log(_syslog.LOG_INFO, msg)
2271 def warn(self, msg):
2272 self._log(_syslog.LOG_WARNING, "WARNING: " + msg)
2274 def _xs_read_path(self, path):
2275 val = self.xs.read(self._xbt, path)
2276 #self.info("read %s = '%s'" % (path, val))
2277 return val
2279 def _xs_write_path(self, path, val):
2280 self.xs.write(self._xbt, path, val)
2281 self.info("wrote %s = '%s'" % (path, val))
2283 def _xs_rm_path(self, path):
2284 self.xs.rm(self._xbt, path)
2285 self.info("removed %s" % path)
2287 def read(self, key):
2288 return self._xs_read_path(self.xs_path(key))
2290 def has_xs_key(self, key):
2291 return self.read(key) is not None
2293 def write(self, key, val):
2294 self._xs_write_path(self.xs_path(key), val)
2296 def rm(self, key):
2297 self._xs_rm_path(self.xs_path(key))
2299 def exists(self):
2300 return self.has_xs_key(None)
2302 def begin(self):
2303 assert(self._xbt == XenbusDevice.XBT_NIL)
2304 self._xbt = self.xs.transaction_start()
2306 def commit(self):
2307 ok = self.xs.transaction_end(self._xbt, 0)
2308 self._xbt = XenbusDevice.XBT_NIL
2309 return ok
2311 def abort(self):
2312 ok = self.xs.transaction_end(self._xbt, 1)
2313 assert(ok == True)
2314 self._xbt = XenbusDevice.XBT_NIL
2316 def create_physical_device(self):
2317 """The standard protocol is: toolstack writes 'params', linux hotplug
2318 script translates this into physical-device=%x:%x"""
2319 if self.has_xs_key("physical-device"):
2320 return
2321 try:
2322 params = self.read("params")
2323 frontend = self.read("frontend")
2324 is_cdrom = self._xs_read_path("%s/device-type") == "cdrom"
2325 # We don't have PV drivers for CDROM devices, so we prevent blkback
2326 # from opening the physical-device
2327 if not(is_cdrom):
2328 major_minor = os.stat(params).st_rdev
2329 major, minor = divmod(major_minor, 256)
2330 self.write("physical-device", "%x:%x" % (major, minor))
2331 except:
2332 util.logException("BLKTAP2:create_physical_device")
2334 def signal_hotplug(self, online=True):
2335 xapi_path = "/xapi/%d/hotplug/%s/%d/hotplug" % (self.domid,
2336 self.XENBUS_DEVTYPE,
2337 self.devid)
2338 upstream_path = self.xs_path("hotplug-status")
2339 if online:
2340 self._xs_write_path(xapi_path, "online")
2341 self._xs_write_path(upstream_path, "connected")
2342 else:
2343 self._xs_rm_path(xapi_path)
2344 self._xs_rm_path(upstream_path)
2346 def sysfs_devname(self):
2347 return "%s-%d-%d" % (self.XENBUS_DEVTYPE,
2348 self.domid, self.devid)
2350 def __str__(self):
2351 return self.sysfs_devname()
2353 @classmethod
2354 def find(cls):
2355 pattern = "/sys/bus/%s/devices/%s*" % (cls.SYSFS_BUSTYPE,
2356 cls.XENBUS_DEVTYPE)
2357 for path in glob.glob(pattern):
2359 name = os.path.basename(path)
2360 (_type, domid, devid) = name.split('-')
2362 yield cls(domid, devid)
2365class XenBackendDevice(XenbusDevice):
2366 """Xenbus backend device"""
2367 SYSFS_BUSTYPE = "xen-backend"
2369 @classmethod
2370 def from_xs_path(cls, _path):
2371 (_backend, _type, domid, devid) = _path.split('/')
2373 assert _backend == 'backend'
2374 assert _type == cls.XENBUS_DEVTYPE
2376 domid = int(domid)
2377 devid = int(devid)
2379 return cls(domid, devid)
2382class Blkback(XenBackendDevice):
2383 """A blkback VBD"""
2385 XENBUS_DEVTYPE = "vbd"
2387 def __init__(self, domid, devid):
2388 XenBackendDevice.__init__(self, domid, devid)
2389 self._phy = None
2390 self._vdi_uuid = None
2391 self._q_state = None
2392 self._q_events = None
2394 class XenstoreValueError(Exception):
2395 KEY = None
2397 def __init__(self, vbd, _str):
2398 self.vbd = vbd
2399 self.str = _str
2401 def __str__(self):
2402 return "Backend %s " % self.vbd + \
2403 "has %s = %s" % (self.KEY, self.str)
2405 class PhysicalDeviceError(XenstoreValueError):
2406 KEY = "physical-device"
2408 class PhysicalDevice(object):
2410 def __init__(self, major, minor):
2411 self.major = int(major)
2412 self.minor = int(minor)
2414 @classmethod
2415 def from_xbdev(cls, xbdev):
2417 phy = xbdev.read("physical-device")
2419 try:
2420 major, minor = phy.split(':')
2421 major = int(major, 0x10)
2422 minor = int(minor, 0x10)
2423 except Exception as e:
2424 raise xbdev.PhysicalDeviceError(xbdev, phy)
2426 return cls(major, minor)
2428 def makedev(self):
2429 return os.makedev(self.major, self.minor)
2431 def is_tap(self):
2432 return self.major == Tapdisk.major()
2434 def __str__(self):
2435 return "%s:%s" % (self.major, self.minor)
2437 def __eq__(self, other):
2438 return \
2439 self.major == other.major and \
2440 self.minor == other.minor
2442 def get_physical_device(self):
2443 if not self._phy:
2444 self._phy = self.PhysicalDevice.from_xbdev(self)
2445 return self._phy
2447 class QueueEvents(Attribute):
2448 """Blkback sysfs node to select queue-state event
2449 notifications emitted."""
2451 SYSFS_NODENAME = "queue_events"
2453 QUEUE_RUNNING = (1 << 0)
2454 QUEUE_PAUSE_DONE = (1 << 1)
2455 QUEUE_SHUTDOWN_DONE = (1 << 2)
2456 QUEUE_PAUSE_REQUEST = (1 << 3)
2457 QUEUE_SHUTDOWN_REQUEST = (1 << 4)
2459 def get_mask(self):
2460 return int(self.readline(), 0x10)
2462 def set_mask(self, mask):
2463 self.writeline("0x%x" % mask)
2465 def get_queue_events(self):
2466 if not self._q_events:
2467 self._q_events = self.QueueEvents.from_kobject(self)
2468 return self._q_events
2470 def get_vdi_uuid(self):
2471 if not self._vdi_uuid:
2472 self._vdi_uuid = self.read("sm-data/vdi-uuid")
2473 return self._vdi_uuid
2475 def pause_requested(self):
2476 return self.has_xs_key("pause")
2478 def shutdown_requested(self):
2479 return self.has_xs_key("shutdown-request")
2481 def shutdown_done(self):
2482 return self.has_xs_key("shutdown-done")
2484 def running(self):
2485 return self.has_xs_key('queue-0/kthread-pid')
2487 @classmethod
2488 def find_by_physical_device(cls, phy):
2489 for dev in cls.find():
2490 try:
2491 _phy = dev.get_physical_device()
2492 except cls.PhysicalDeviceError:
2493 continue
2495 if _phy == phy:
2496 yield dev
2498 @classmethod
2499 def find_by_tap_minor(cls, minor):
2500 phy = cls.PhysicalDevice(Tapdisk.major(), minor)
2501 return cls.find_by_physical_device(phy)
2503 @classmethod
2504 def find_by_tap(cls, tapdisk):
2505 return cls.find_by_tap_minor(tapdisk.minor)
2507 def has_tap(self):
2509 if not self.can_tap():
2510 return False
2512 phy = self.get_physical_device()
2513 if phy:
2514 return phy.is_tap()
2516 return False
2518 def is_bare_hvm(self):
2519 """File VDIs for bare HVM. These are directly accessible by Qemu."""
2520 try:
2521 self.get_physical_device()
2523 except self.PhysicalDeviceError as e:
2524 vdi_type = self.read("type")
2526 self.info("HVM VDI: type=%s" % vdi_type)
2528 if e.str is not None or vdi_type != 'file':
2529 raise
2531 return True
2533 return False
2535 def can_tap(self):
2536 return not self.is_bare_hvm()
2539class BlkbackEventHandler(UEventHandler):
2541 LOG_FACILITY = _syslog.LOG_DAEMON
2543 def __init__(self, ident=None, action=None):
2544 if not ident:
2545 ident = self.__class__.__name__
2547 self.ident = ident
2548 self._vbd = None
2549 self._tapdisk = None
2551 UEventHandler.__init__(self)
2553 def run(self):
2555 self.xs_path = self.getenv('XENBUS_PATH')
2556 openlog(str(self), 0, self.LOG_FACILITY)
2558 UEventHandler.run(self)
2560 def __str__(self):
2562 try:
2563 path = self.xs_path
2564 except:
2565 path = None
2567 try:
2568 action = self.get_action()
2569 except:
2570 action = None
2572 return "%s[%s](%s)" % (self.ident, action, path)
2574 def _log(self, prio, msg):
2575 syslog(prio, msg)
2576 util.SMlog("%s: " % self + msg)
2578 def info(self, msg):
2579 self._log(_syslog.LOG_INFO, msg)
2581 def warn(self, msg):
2582 self._log(_syslog.LOG_WARNING, "WARNING: " + msg)
2584 def error(self, msg):
2585 self._log(_syslog.LOG_ERR, "ERROR: " + msg)
2587 def get_vbd(self):
2588 if not self._vbd:
2589 self._vbd = Blkback.from_xs_path(self.xs_path)
2590 return self._vbd
2592 def get_tapdisk(self):
2593 if not self._tapdisk:
2594 minor = self.get_vbd().get_physical_device().minor
2595 self._tapdisk = Tapdisk.from_minor(minor)
2596 return self._tapdisk
2597 #
2598 # Events
2599 #
2601 def __add(self):
2602 vbd = self.get_vbd()
2603 # Manage blkback transitions
2604 # self._manage_vbd()
2606 vbd.create_physical_device()
2608 vbd.signal_hotplug()
2610 @retried(backoff=.5, limit=10)
2611 def add(self):
2612 try:
2613 self.__add()
2614 except Attribute.NoSuchAttribute as e:
2615 #
2616 # FIXME: KOBJ_ADD is racing backend.probe, which
2617 # registers device attributes. So poll a little.
2618 #
2619 self.warn("%s, still trying." % e)
2620 raise RetryLoop.TransientFailure(e)
2622 def __change(self):
2623 vbd = self.get_vbd()
2625 # 1. Pause or resume tapdisk (if there is one)
2627 if vbd.has_tap():
2628 pass
2629 #self._pause_update_tap()
2631 # 2. Signal Xapi.VBD.pause/resume completion
2633 self._signal_xapi()
2635 def change(self):
2636 vbd = self.get_vbd()
2638 # NB. Beware of spurious change events between shutdown
2639 # completion and device removal. Also, Xapi.VM.migrate will
2640 # hammer a couple extra shutdown-requests into the source VBD.
2642 while True:
2643 vbd.begin()
2645 if not vbd.exists() or \
2646 vbd.shutdown_done():
2647 break
2649 self.__change()
2651 if vbd.commit():
2652 return
2654 vbd.abort()
2655 self.info("spurious uevent, ignored.")
2657 def remove(self):
2658 vbd = self.get_vbd()
2660 vbd.signal_hotplug(False)
2662 ACTIONS = {'add': add,
2663 'change': change,
2664 'remove': remove}
2665 #
2666 # VDI.pause
2667 #
2669 def _tap_should_pause(self):
2670 """Enumerate all VBDs on our tapdisk. Returns true iff any was
2671 paused"""
2673 tapdisk = self.get_tapdisk()
2674 TapState = Tapdisk.PauseState
2676 PAUSED = 'P'
2677 RUNNING = 'R'
2678 PAUSED_SHUTDOWN = 'P,S'
2679 # NB. Shutdown/paused is special. We know it's not going
2680 # to restart again, so it's a RUNNING. Still better than
2681 # backtracking a removed device during Vbd.unplug completion.
2683 next = TapState.RUNNING
2684 vbds = {}
2686 for vbd in Blkback.find_by_tap(tapdisk):
2687 name = str(vbd)
2689 pausing = vbd.pause_requested()
2690 closing = vbd.shutdown_requested()
2691 running = vbd.running()
2693 if pausing:
2694 if closing and not running:
2695 vbds[name] = PAUSED_SHUTDOWN
2696 else:
2697 vbds[name] = PAUSED
2698 next = TapState.PAUSED
2700 else:
2701 vbds[name] = RUNNING
2703 self.info("tapdev%d (%s): %s -> %s"
2704 % (tapdisk.minor, tapdisk.pause_state(),
2705 vbds, next))
2707 return next == TapState.PAUSED
2709 def _pause_update_tap(self):
2710 vbd = self.get_vbd()
2712 if self._tap_should_pause():
2713 self._pause_tap()
2714 else:
2715 self._resume_tap()
2717 def _pause_tap(self):
2718 tapdisk = self.get_tapdisk()
2720 if not tapdisk.is_paused():
2721 self.info("pausing %s" % tapdisk)
2722 tapdisk.pause()
2724 def _resume_tap(self):
2725 tapdisk = self.get_tapdisk()
2727 # NB. Raw VDI snapshots. Refresh the physical path and
2728 # type while resuming.
2729 vbd = self.get_vbd()
2730 vdi_uuid = vbd.get_vdi_uuid()
2732 if tapdisk.is_paused():
2733 self.info("loading vdi uuid=%s" % vdi_uuid)
2734 vdi = VDI.from_cli(vdi_uuid)
2735 _type = vdi.get_tap_type()
2736 path = vdi.get_phy_path()
2737 self.info("resuming %s on %s:%s" % (tapdisk, _type, path))
2738 tapdisk.unpause(_type, path)
2739 #
2740 # VBD.pause/shutdown
2741 #
2743 def _manage_vbd(self):
2744 vbd = self.get_vbd()
2745 # NB. Hook into VBD state transitions.
2747 events = vbd.get_queue_events()
2749 mask = 0
2750 mask |= events.QUEUE_PAUSE_DONE # pause/unpause
2751 mask |= events.QUEUE_SHUTDOWN_DONE # shutdown
2752 # TODO: mask |= events.QUEUE_SHUTDOWN_REQUEST, for shutdown=force
2753 # TODO: mask |= events.QUEUE_RUNNING, for ionice updates etc
2755 events.set_mask(mask)
2756 self.info("wrote %s = %#02x" % (events.path, mask))
2758 def _signal_xapi(self):
2759 vbd = self.get_vbd()
2761 pausing = vbd.pause_requested()
2762 closing = vbd.shutdown_requested()
2763 running = vbd.running()
2765 handled = 0
2767 if pausing and not running:
2768 if 'pause-done' not in vbd:
2769 vbd.write('pause-done', '')
2770 handled += 1
2772 if not pausing:
2773 if 'pause-done' in vbd:
2774 vbd.rm('pause-done')
2775 handled += 1
2777 if closing and not running:
2778 if 'shutdown-done' not in vbd:
2779 vbd.write('shutdown-done', '')
2780 handled += 1
2782 if handled > 1:
2783 self.warn("handled %d events, " % handled +
2784 "pausing=%s closing=%s running=%s" % \
2785 (pausing, closing, running))
2787if __name__ == '__main__': 2787 ↛ 2789line 2787 didn't jump to line 2789, because the condition on line 2787 was never true
2789 import sys
2790 prog = os.path.basename(sys.argv[0])
2792 #
2793 # Simple CLI interface for manual operation
2794 #
2795 # tap.* level calls go down to local Tapdisk()s (by physical path)
2796 # vdi.* level calls run the plugin calls across host boundaries.
2797 #
2799 def usage(stream):
2800 print("usage: %s tap.{list|major}" % prog, file=stream)
2801 print(" %s tap.{launch|find|get|pause|" % prog + \
2802 "unpause|shutdown|stats} {[<tt>:]<path>} | [minor=]<int> | .. }", file=stream)
2803 print(" %s vbd.uevent" % prog, file=stream)
2805 try:
2806 cmd = sys.argv[1]
2807 except IndexError:
2808 usage(sys.stderr)
2809 sys.exit(1)
2811 try:
2812 _class, method = cmd.split('.')
2813 except:
2814 usage(sys.stderr)
2815 sys.exit(1)
2817 #
2818 # Local Tapdisks
2819 #
2821 if cmd == 'tap.major':
2823 print("%d" % Tapdisk.major())
2825 elif cmd == 'tap.launch':
2827 tapdisk = Tapdisk.launch_from_arg(sys.argv[2])
2828 print("Launched %s" % tapdisk, file=sys.stderr)
2830 elif _class == 'tap':
2832 attrs = {}
2833 for item in sys.argv[2:]:
2834 try:
2835 key, val = item.split('=')
2836 attrs[key] = val
2837 continue
2838 except ValueError:
2839 pass
2841 try:
2842 attrs['minor'] = int(item)
2843 continue
2844 except ValueError:
2845 pass
2847 try:
2848 arg = Tapdisk.Arg.parse(item)
2849 attrs['_type'] = arg.type
2850 attrs['path'] = arg.path
2851 continue
2852 except Tapdisk.Arg.InvalidArgument:
2853 pass
2855 attrs['path'] = item
2857 if cmd == 'tap.list':
2859 for tapdisk in Tapdisk.list( ** attrs):
2860 blktap = tapdisk.get_blktap()
2861 print(tapdisk, end=' ')
2862 print("%s: task=%s pool=%s" % \
2863 (blktap,
2864 blktap.get_task_pid(),
2865 blktap.get_pool_name()))
2867 elif cmd == 'tap.vbds':
2868 # Find all Blkback instances for a given tapdisk
2870 for tapdisk in Tapdisk.list( ** attrs):
2871 print("%s:" % tapdisk, end=' ')
2872 for vbd in Blkback.find_by_tap(tapdisk):
2873 print(vbd, end=' ')
2874 print()
2876 else:
2878 if not attrs:
2879 usage(sys.stderr)
2880 sys.exit(1)
2882 try:
2883 tapdisk = Tapdisk.get( ** attrs)
2884 except TypeError:
2885 usage(sys.stderr)
2886 sys.exit(1)
2888 if cmd == 'tap.shutdown':
2889 # Shutdown a running tapdisk, or raise
2890 tapdisk.shutdown()
2891 print("Shut down %s" % tapdisk, file=sys.stderr)
2893 elif cmd == 'tap.pause':
2894 # Pause an unpaused tapdisk, or raise
2895 tapdisk.pause()
2896 print("Paused %s" % tapdisk, file=sys.stderr)
2898 elif cmd == 'tap.unpause':
2899 # Unpause a paused tapdisk, or raise
2900 tapdisk.unpause()
2901 print("Unpaused %s" % tapdisk, file=sys.stderr)
2903 elif cmd == 'tap.stats':
2904 # Gather tapdisk status
2905 stats = tapdisk.stats()
2906 print("%s:" % tapdisk)
2907 print(json.dumps(stats, indent=True))
2909 else:
2910 usage(sys.stderr)
2911 sys.exit(1)
2913 elif cmd == 'vbd.uevent':
2915 hnd = BlkbackEventHandler(cmd)
2917 if not sys.stdin.isatty():
2918 try:
2919 hnd.run()
2920 except Exception as e:
2921 hnd.error("Unhandled Exception: %s" % e)
2923 import traceback
2924 _type, value, tb = sys.exc_info()
2925 trace = traceback.format_exception(_type, value, tb)
2926 for entry in trace:
2927 for line in entry.rstrip().split('\n'):
2928 util.SMlog(line)
2929 else:
2930 hnd.run()
2932 elif cmd == 'vbd.list':
2934 for vbd in Blkback.find():
2935 print(vbd, \
2936 "physical-device=%s" % vbd.get_physical_device(), \
2937 "pause=%s" % vbd.pause_requested())
2939 else:
2940 usage(sys.stderr)
2941 sys.exit(1)