bdev.py 50.3 KB
Newer Older
Iustin Pop's avatar
Iustin Pop committed
1
#
Iustin Pop's avatar
Iustin Pop committed
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
#

# Copyright (C) 2006, 2007 Google Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.


"""Block device abstraction"""

import re
import time
import errno
27
import pyparsing as pyp
Manuel Franceschini's avatar
Manuel Franceschini committed
28
import os
29
import logging
Iustin Pop's avatar
Iustin Pop committed
30
31
32

from ganeti import utils
from ganeti import errors
33
from ganeti import constants
Iustin Pop's avatar
Iustin Pop committed
34
35
36
37
38
39
40
41
42
43
44
45


class BlockDev(object):
  """Block device abstract class.

  A block device can be in the following states:
    - not existing on the system, and by `Create()` it goes into:
    - existing but not setup/not active, and by `Assemble()` goes into:
    - active read-write and by `Open()` it goes into
    - online (=used, or ready for use)

  A device can also be online but read-only, however we are not using
46
47
48
  the readonly state (LV has it, if needed in the future) and we are
  usually looking at this like at a stack, so it's easier to
  conceptualise the transition from not-existing to online and back
Iustin Pop's avatar
Iustin Pop committed
49
50
51
52
53
54
55
56
57
58
59
60
61
62
  like a linear one.

  The many different states of the device are due to the fact that we
  need to cover many device types:
    - logical volumes are created, lvchange -a y $lv, and used
    - drbd devices are attached to a local disk/remote peer and made primary

  A block device is identified by three items:
    - the /dev path of the device (dynamic)
    - a unique ID of the device (static)
    - it's major/minor pair (dynamic)

  Not all devices implement both the first two as distinct items. LVM
  logical volumes have their unique ID (the pair volume group, logical
63
64
65
  volume name) in a 1-to-1 relation to the dev path. For DRBD devices,
  the /dev path is again dynamic and the unique id is the pair (host1,
  dev1), (host2, dev2).
Iustin Pop's avatar
Iustin Pop committed
66
67
68

  You can get to a device in two ways:
    - creating the (real) device, which returns you
69
      an attached instance (lvcreate)
Iustin Pop's avatar
Iustin Pop committed
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
    - attaching of a python instance to an existing (real) device

  The second point, the attachement to a device, is different
  depending on whether the device is assembled or not. At init() time,
  we search for a device with the same unique_id as us. If found,
  good. It also means that the device is already assembled. If not,
  after assembly we'll have our correct major/minor.

  """
  def __init__(self, unique_id, children):
    self._children = children
    self.dev_path = None
    self.unique_id = unique_id
    self.major = None
    self.minor = None
85
    self.attached = False
Iustin Pop's avatar
Iustin Pop committed
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107

  def Assemble(self):
    """Assemble the device from its components.

    If this is a plain block device (e.g. LVM) than assemble does
    nothing, as the LVM has no children and we don't put logical
    volumes offline.

    One guarantee is that after the device has been assembled, it
    knows its major/minor numbers. This allows other devices (usually
    parents) to probe correctly for their children.

    """
    status = True
    for child in self._children:
      if not isinstance(child, BlockDev):
        raise TypeError("Invalid child passed of type '%s'" % type(child))
      if not status:
        break
      status = status and child.Assemble()
      if not status:
        break
108
109
110
111
112
113
114

      try:
        child.Open()
      except errors.BlockDeviceError:
        for child in self._children:
          child.Shutdown()
        raise
Iustin Pop's avatar
Iustin Pop committed
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149

    if not status:
      for child in self._children:
        child.Shutdown()
    return status

  def Attach(self):
    """Find a device which matches our config and attach to it.

    """
    raise NotImplementedError

  def Close(self):
    """Notifies that the device will no longer be used for I/O.

    """
    raise NotImplementedError

  @classmethod
  def Create(cls, unique_id, children, size):
    """Create the device.

    If the device cannot be created, it will return None
    instead. Error messages go to the logging system.

    Note that for some devices, the unique_id is used, and for other,
    the children. The idea is that these two, taken together, are
    enough for both creation and assembly (later).

    """
    raise NotImplementedError

  def Remove(self):
    """Remove this device.

150
151
152
    This makes sense only for some of the device types: LV and file
    storeage. Also note that if the device can't attach, the removal
    can't be completed.
Iustin Pop's avatar
Iustin Pop committed
153
154
155
156

    """
    raise NotImplementedError

Iustin Pop's avatar
Iustin Pop committed
157
158
159
160
161
162
163
164
  def Rename(self, new_id):
    """Rename this device.

    This may or may not make sense for a given device type.

    """
    raise NotImplementedError

Iustin Pop's avatar
Iustin Pop committed
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
  def Open(self, force=False):
    """Make the device ready for use.

    This makes the device ready for I/O. For now, just the DRBD
    devices need this.

    The force parameter signifies that if the device has any kind of
    --force thing, it should be used, we know what we are doing.

    """
    raise NotImplementedError

  def Shutdown(self):
    """Shut down the device, freeing its children.

    This undoes the `Assemble()` work, except for the child
    assembling; as such, the children on the device are still
    assembled after this call.

    """
    raise NotImplementedError

  def SetSyncSpeed(self, speed):
    """Adjust the sync speed of the mirror.

    In case this is not a mirroring device, this is no-op.

    """
    result = True
    if self._children:
      for child in self._children:
        result = result and child.SetSyncSpeed(speed)
    return result

  def GetSyncStatus(self):
    """Returns the sync status of the device.

    If this device is a mirroring device, this function returns the
    status of the mirror.

205
    If sync_percent is None, it means the device is not syncing.
Iustin Pop's avatar
Iustin Pop committed
206
207

    If estimated_time is None, it means we can't estimate
208
209
    the time needed, otherwise it's the time left in seconds.

Iustin Pop's avatar
Iustin Pop committed
210
211
212
213
    If is_degraded is True, it means the device is missing
    redundancy. This is usually a sign that something went wrong in
    the device setup, if sync_percent is None.

214
215
216
217
    The ldisk parameter represents the degradation of the local
    data. This is only valid for some devices, the rest will always
    return False (not degraded).

Iustin Pop's avatar
Iustin Pop committed
218
219
220
    @rtype: tuple
    @return: (sync_percent, estimated_time, is_degraded, ldisk)

Iustin Pop's avatar
Iustin Pop committed
221
    """
222
    return None, None, False, False
Iustin Pop's avatar
Iustin Pop committed
223
224
225
226
227
228
229
230
231
232


  def CombinedSyncStatus(self):
    """Calculate the mirror status recursively for our children.

    The return value is the same as for `GetSyncStatus()` except the
    minimum percent and maximum time are calculated across our
    children.

    """
233
    min_percent, max_time, is_degraded, ldisk = self.GetSyncStatus()
Iustin Pop's avatar
Iustin Pop committed
234
235
    if self._children:
      for child in self._children:
236
        c_percent, c_time, c_degraded, c_ldisk = child.GetSyncStatus()
Iustin Pop's avatar
Iustin Pop committed
237
238
239
240
241
242
243
244
245
        if min_percent is None:
          min_percent = c_percent
        elif c_percent is not None:
          min_percent = min(min_percent, c_percent)
        if max_time is None:
          max_time = c_time
        elif c_time is not None:
          max_time = max(max_time, c_time)
        is_degraded = is_degraded or c_degraded
246
247
        ldisk = ldisk or c_ldisk
    return min_percent, max_time, is_degraded, ldisk
Iustin Pop's avatar
Iustin Pop committed
248
249


250
251
252
253
254
255
256
257
258
  def SetInfo(self, text):
    """Update metadata with info text.

    Only supported for some device types.

    """
    for child in self._children:
      child.SetInfo(text)

259
260
261
  def Grow(self, amount):
    """Grow the block device.

Iustin Pop's avatar
Iustin Pop committed
262
    @param amount: the amount (in mebibytes) to grow with
263
264
265

    """
    raise NotImplementedError
266

Iustin Pop's avatar
Iustin Pop committed
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
  def __repr__(self):
    return ("<%s: unique_id: %s, children: %s, %s:%s, %s>" %
            (self.__class__, self.unique_id, self._children,
             self.major, self.minor, self.dev_path))


class LogicalVolume(BlockDev):
  """Logical Volume block device.

  """
  def __init__(self, unique_id, children):
    """Attaches to a LV device.

    The unique_id is a tuple (vg_name, lv_name)

    """
    super(LogicalVolume, self).__init__(unique_id, children)
    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
      raise ValueError("Invalid configuration data %s" % str(unique_id))
    self._vg_name, self._lv_name = unique_id
    self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name)
Iustin Pop's avatar
Iustin Pop committed
288
289
    self._degraded = True
    self.major = self.minor = None
Iustin Pop's avatar
Iustin Pop committed
290
291
292
293
294
295
296
297
298
299
300
301
    self.Attach()

  @classmethod
  def Create(cls, unique_id, children, size):
    """Create a new logical volume.

    """
    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
      raise ValueError("Invalid configuration data %s" % str(unique_id))
    vg_name, lv_name = unique_id
    pvs_info = cls.GetPVInfo(vg_name)
    if not pvs_info:
302
303
      raise errors.BlockDeviceError("Can't compute PV info for vg %s" %
                                    vg_name)
Iustin Pop's avatar
Iustin Pop committed
304
305
    pvs_info.sort()
    pvs_info.reverse()
306
307
308
309
310
311

    pvlist = [ pv[1] for pv in pvs_info ]
    free_size = sum([ pv[0] for pv in pvs_info ])

    # The size constraint should have been checked from the master before
    # calling the create function.
Iustin Pop's avatar
Iustin Pop committed
312
    if free_size < size:
313
314
      raise errors.BlockDeviceError("Not enough free space: required %s,"
                                    " available %s" % (size, free_size))
Iustin Pop's avatar
Iustin Pop committed
315
    result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-n%s" % lv_name,
316
                           vg_name] + pvlist)
Iustin Pop's avatar
Iustin Pop committed
317
    if result.failed:
318
319
      raise errors.BlockDeviceError("%s - %s" % (result.fail_reason,
                                                result.output))
Iustin Pop's avatar
Iustin Pop committed
320
321
322
323
324
325
    return LogicalVolume(unique_id, children)

  @staticmethod
  def GetPVInfo(vg_name):
    """Get the free space info for PVs in a volume group.

Iustin Pop's avatar
Iustin Pop committed
326
    @param vg_name: the volume group name
Iustin Pop's avatar
Iustin Pop committed
327

Iustin Pop's avatar
Iustin Pop committed
328
329
    @rtype: list
    @return: list of tuples (free_space, name) with free_space in mebibytes
330

Iustin Pop's avatar
Iustin Pop committed
331
332
333
334
335
336
    """
    command = ["pvs", "--noheadings", "--nosuffix", "--units=m",
               "-opv_name,vg_name,pv_free,pv_attr", "--unbuffered",
               "--separator=:"]
    result = utils.RunCmd(command)
    if result.failed:
337
338
      logging.error("Can't get the PV information: %s - %s",
                    result.fail_reason, result.output)
Iustin Pop's avatar
Iustin Pop committed
339
340
341
342
343
      return None
    data = []
    for line in result.stdout.splitlines():
      fields = line.strip().split(':')
      if len(fields) != 4:
344
        logging.error("Can't parse pvs output: line '%s'", line)
Iustin Pop's avatar
Iustin Pop committed
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
        return None
      # skip over pvs from another vg or ones which are not allocatable
      if fields[1] != vg_name or fields[3][0] != 'a':
        continue
      data.append((float(fields[2]), fields[0]))

    return data

  def Remove(self):
    """Remove this logical volume.

    """
    if not self.minor and not self.Attach():
      # the LV does not exist
      return True
    result = utils.RunCmd(["lvremove", "-f", "%s/%s" %
                           (self._vg_name, self._lv_name)])
    if result.failed:
363
364
      logging.error("Can't lvremove: %s - %s",
                    result.fail_reason, result.output)
Iustin Pop's avatar
Iustin Pop committed
365
366
367

    return not result.failed

Iustin Pop's avatar
Iustin Pop committed
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
  def Rename(self, new_id):
    """Rename this logical volume.

    """
    if not isinstance(new_id, (tuple, list)) or len(new_id) != 2:
      raise errors.ProgrammerError("Invalid new logical id '%s'" % new_id)
    new_vg, new_name = new_id
    if new_vg != self._vg_name:
      raise errors.ProgrammerError("Can't move a logical volume across"
                                   " volume groups (from %s to to %s)" %
                                   (self._vg_name, new_vg))
    result = utils.RunCmd(["lvrename", new_vg, self._lv_name, new_name])
    if result.failed:
      raise errors.BlockDeviceError("Failed to rename the logical volume: %s" %
                                    result.output)
383
384
385
    self._lv_name = new_name
    self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name)

Iustin Pop's avatar
Iustin Pop committed
386
387
388
389
  def Attach(self):
    """Attach to an existing LV.

    This method will try to see if an existing and active LV exists
390
    which matches our name. If so, its major/minor will be
Iustin Pop's avatar
Iustin Pop committed
391
392
393
    recorded.

    """
394
    self.attached = False
Iustin Pop's avatar
Iustin Pop committed
395
396
397
    result = utils.RunCmd(["lvs", "--noheadings", "--separator=,",
                           "-olv_attr,lv_kernel_major,lv_kernel_minor",
                           self.dev_path])
Iustin Pop's avatar
Iustin Pop committed
398
    if result.failed:
399
400
      logging.error("Can't find LV %s: %s, %s",
                    self.dev_path, result.fail_reason, result.output)
Iustin Pop's avatar
Iustin Pop committed
401
      return False
Iustin Pop's avatar
Iustin Pop committed
402
403
404
    out = result.stdout.strip().rstrip(',')
    out = out.split(",")
    if len(out) != 3:
405
      logging.error("Can't parse LVS output, len(%s) != 3", str(out))
Iustin Pop's avatar
Iustin Pop committed
406
407
408
409
      return False

    status, major, minor = out[:3]
    if len(status) != 6:
410
      logging.error("lvs lv_attr is not 6 characters (%s)", status)
Iustin Pop's avatar
Iustin Pop committed
411
412
413
414
415
416
      return False

    try:
      major = int(major)
      minor = int(minor)
    except ValueError, err:
417
      logging.error("lvs major/minor cannot be parsed: %s", str(err))
Iustin Pop's avatar
Iustin Pop committed
418
419
420
421
422

    self.major = major
    self.minor = minor
    self._degraded = status[0] == 'v' # virtual volume, i.e. doesn't backing
                                      # storage
423
    self.attached = True
Iustin Pop's avatar
Iustin Pop committed
424
    return True
Iustin Pop's avatar
Iustin Pop committed
425
426
427
428

  def Assemble(self):
    """Assemble the device.

429
430
431
    We alway run `lvchange -ay` on the LV to ensure it's active before
    use, as there were cases when xenvg was not active after boot
    (also possibly after disk issues).
Iustin Pop's avatar
Iustin Pop committed
432
433

    """
434
435
    result = utils.RunCmd(["lvchange", "-ay", self.dev_path])
    if result.failed:
436
      logging.error("Can't activate lv %s: %s", self.dev_path, result.output)
437
438
      return False
    return self.Attach()
Iustin Pop's avatar
Iustin Pop committed
439
440
441
442
443
444
445
446
447
448

  def Shutdown(self):
    """Shutdown the device.

    This is a no-op for the LV device type, as we don't deactivate the
    volumes on shutdown.

    """
    return True

449
450
451
452
453
454
455
456
  def GetSyncStatus(self):
    """Returns the sync status of the device.

    If this device is a mirroring device, this function returns the
    status of the mirror.

    For logical volumes, sync_percent and estimated_time are always
    None (no recovery in progress, as we don't handle the mirrored LV
457
458
    case). The is_degraded parameter is the inverse of the ldisk
    parameter.
459

460
461
462
463
464
    For the ldisk parameter, we check if the logical volume has the
    'virtual' type, which means it's not backed by existing storage
    anymore (read from it return I/O error). This happens after a
    physical disk failure and subsequent 'vgreduce --removemissing' on
    the volume group.
465

Iustin Pop's avatar
Iustin Pop committed
466
467
    The status was already read in Attach, so we just return it.

Iustin Pop's avatar
Iustin Pop committed
468
469
470
    @rtype: tuple
    @return: (sync_percent, estimated_time, is_degraded, ldisk)

471
    """
Iustin Pop's avatar
Iustin Pop committed
472
    return None, None, self._degraded, self._degraded
473

Iustin Pop's avatar
Iustin Pop committed
474
475
476
477
478
479
  def Open(self, force=False):
    """Make the device ready for I/O.

    This is a no-op for the LV device type.

    """
480
    pass
Iustin Pop's avatar
Iustin Pop committed
481
482
483
484
485
486
487

  def Close(self):
    """Notifies that the device will no longer be used for I/O.

    This is a no-op for the LV device type.

    """
488
    pass
Iustin Pop's avatar
Iustin Pop committed
489
490
491
492
493
494
495
496
497
498
499
500
501

  def Snapshot(self, size):
    """Create a snapshot copy of an lvm block device.

    """
    snap_name = self._lv_name + ".snap"

    # remove existing snapshot if found
    snap = LogicalVolume((self._vg_name, snap_name), None)
    snap.Remove()

    pvs_info = self.GetPVInfo(self._vg_name)
    if not pvs_info:
502
503
      raise errors.BlockDeviceError("Can't compute PV info for vg %s" %
                                    self._vg_name)
Iustin Pop's avatar
Iustin Pop committed
504
505
506
507
    pvs_info.sort()
    pvs_info.reverse()
    free_size, pv_name = pvs_info[0]
    if free_size < size:
508
509
      raise errors.BlockDeviceError("Not enough free space: required %s,"
                                    " available %s" % (size, free_size))
Iustin Pop's avatar
Iustin Pop committed
510
511
512
513

    result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-s",
                           "-n%s" % snap_name, self.dev_path])
    if result.failed:
514
515
516
      raise errors.BlockDeviceError("command: %s error: %s - %s" %
                                    (result.cmd, result.fail_reason,
                                     result.output))
Iustin Pop's avatar
Iustin Pop committed
517
518
519

    return snap_name

520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
  def SetInfo(self, text):
    """Update metadata with info text.

    """
    BlockDev.SetInfo(self, text)

    # Replace invalid characters
    text = re.sub('^[^A-Za-z0-9_+.]', '_', text)
    text = re.sub('[^-A-Za-z0-9_+.]', '_', text)

    # Only up to 128 characters are allowed
    text = text[:128]

    result = utils.RunCmd(["lvchange", "--addtag", text,
                           self.dev_path])
    if result.failed:
536
537
538
      raise errors.BlockDeviceError("Command: %s error: %s - %s" %
                                    (result.cmd, result.fail_reason,
                                     result.output))
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
  def Grow(self, amount):
    """Grow the logical volume.

    """
    # we try multiple algorithms since the 'best' ones might not have
    # space available in the right place, but later ones might (since
    # they have less constraints); also note that only recent LVM
    # supports 'cling'
    for alloc_policy in "contiguous", "cling", "normal":
      result = utils.RunCmd(["lvextend", "--alloc", alloc_policy,
                             "-L", "+%dm" % amount, self.dev_path])
      if not result.failed:
        return
    raise errors.BlockDeviceError("Can't grow LV %s: %s" %
                                  (self.dev_path, result.output))
554
555


556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
class DRBD8Status(object):
  """A DRBD status representation class.

  Note that this doesn't support unconfigured devices (cs:Unconfigured).

  """
  LINE_RE = re.compile(r"\s*[0-9]+:\s*cs:(\S+)\s+st:([^/]+)/(\S+)"
                       "\s+ds:([^/]+)/(\S+)\s+.*$")
  SYNC_RE = re.compile(r"^.*\ssync'ed:\s*([0-9.]+)%.*"
                       "\sfinish: ([0-9]+):([0-9]+):([0-9]+)\s.*$")

  def __init__(self, procline):
    m = self.LINE_RE.match(procline)
    if not m:
      raise errors.BlockDeviceError("Can't parse input data '%s'" % procline)
    self.cstatus = m.group(1)
    self.lrole = m.group(2)
    self.rrole = m.group(3)
    self.ldisk = m.group(4)
    self.rdisk = m.group(5)

    self.is_standalone = self.cstatus == "StandAlone"
    self.is_wfconn = self.cstatus == "WFConnection"
    self.is_connected = self.cstatus == "Connected"
    self.is_primary = self.lrole == "Primary"
    self.is_secondary = self.lrole == "Secondary"
    self.peer_primary = self.rrole == "Primary"
    self.peer_secondary = self.rrole == "Secondary"
    self.both_primary = self.is_primary and self.peer_primary
    self.both_secondary = self.is_secondary and self.peer_secondary

    self.is_diskless = self.ldisk == "Diskless"
    self.is_disk_uptodate = self.ldisk == "UpToDate"

    m = self.SYNC_RE.match(procline)
    if m:
      self.sync_percent = float(m.group(1))
      hours = int(m.group(2))
      minutes = int(m.group(3))
      seconds = int(m.group(4))
      self.est_time = hours * 3600 + minutes * 60 + seconds
    else:
      self.sync_percent = None
      self.est_time = None

    self.is_sync_target = self.peer_sync_source = self.cstatus == "SyncTarget"
    self.peer_sync_target = self.is_sync_source = self.cstatus == "SyncSource"
    self.is_resync = self.is_sync_target or self.is_sync_source


606
607
class BaseDRBD(BlockDev):
  """Base DRBD class.
Iustin Pop's avatar
Iustin Pop committed
608

609
610
611
  This class contains a few bits of common functionality between the
  0.7 and 8.x versions of DRBD.

612
613
614
  """
  _VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)"
                           r" \(api:(\d+)/proto:(\d+)(?:-(\d+))?\)")
Iustin Pop's avatar
Iustin Pop committed
615

616
617
618
619
  _DRBD_MAJOR = 147
  _ST_UNCONFIGURED = "Unconfigured"
  _ST_WFCONNECTION = "WFConnection"
  _ST_CONNECTED = "Connected"
Iustin Pop's avatar
Iustin Pop committed
620

621
622
  _STATUS_FILE = "/proc/drbd"

623
  @staticmethod
624
  def _GetProcData(filename=_STATUS_FILE):
625
    """Return data from /proc/drbd.
Iustin Pop's avatar
Iustin Pop committed
626
627

    """
628
    stat = open(filename, "r")
629
630
631
632
633
    try:
      data = stat.read().splitlines()
    finally:
      stat.close()
    if not data:
634
      raise errors.BlockDeviceError("Can't read any data from %s" % filename)
635
    return data
Iustin Pop's avatar
Iustin Pop committed
636

637
638
639
  @staticmethod
  def _MassageProcData(data):
    """Transform the output of _GetProdData into a nicer form.
Iustin Pop's avatar
Iustin Pop committed
640

Iustin Pop's avatar
Iustin Pop committed
641
642
    @return: a dictionary of minor: joined lines from /proc/drbd
        for that minor
Iustin Pop's avatar
Iustin Pop committed
643
644

    """
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
    lmatch = re.compile("^ *([0-9]+):.*$")
    results = {}
    old_minor = old_line = None
    for line in data:
      lresult = lmatch.match(line)
      if lresult is not None:
        if old_minor is not None:
          results[old_minor] = old_line
        old_minor = int(lresult.group(1))
        old_line = line
      else:
        if old_minor is not None:
          old_line += " " + line.strip()
    # add last line
    if old_minor is not None:
      results[old_minor] = old_line
    return results
Iustin Pop's avatar
Iustin Pop committed
662

663
664
665
  @classmethod
  def _GetVersion(cls):
    """Return the DRBD version.
Iustin Pop's avatar
Iustin Pop committed
666

667
    This will return a dict with keys:
Iustin Pop's avatar
Iustin Pop committed
668
669
670
671
672
673
      - k_major
      - k_minor
      - k_point
      - api
      - proto
      - proto2 (only on drbd > 8.2.X)
Iustin Pop's avatar
Iustin Pop committed
674
675

    """
676
677
678
679
680
681
    proc_data = cls._GetProcData()
    first_line = proc_data[0].strip()
    version = cls._VERSION_RE.match(first_line)
    if not version:
      raise errors.BlockDeviceError("Can't parse DRBD version from '%s'" %
                                    first_line)
Iustin Pop's avatar
Iustin Pop committed
682

683
684
685
686
687
688
689
690
691
    values = version.groups()
    retval = {'k_major': int(values[0]),
              'k_minor': int(values[1]),
              'k_point': int(values[2]),
              'api': int(values[3]),
              'proto': int(values[4]),
             }
    if values[5] is not None:
      retval['proto2'] = values[5]
Iustin Pop's avatar
Iustin Pop committed
692

693
694
695
696
697
    return retval

  @staticmethod
  def _DevPath(minor):
    """Return the path to a drbd device for a given minor.
Iustin Pop's avatar
Iustin Pop committed
698
699

    """
700
    return "/dev/drbd%d" % minor
Iustin Pop's avatar
Iustin Pop committed
701

702
703
704
  @classmethod
  def _GetUsedDevs(cls):
    """Compute the list of used DRBD devices.
Iustin Pop's avatar
Iustin Pop committed
705
706

    """
707
    data = cls._GetProcData()
Iustin Pop's avatar
Iustin Pop committed
708

709
710
711
712
713
714
715
716
717
718
719
    used_devs = {}
    valid_line = re.compile("^ *([0-9]+): cs:([^ ]+).*$")
    for line in data:
      match = valid_line.match(line)
      if not match:
        continue
      minor = int(match.group(1))
      state = match.group(2)
      if state == cls._ST_UNCONFIGURED:
        continue
      used_devs[minor] = state, line
Iustin Pop's avatar
Iustin Pop committed
720

721
    return used_devs
Iustin Pop's avatar
Iustin Pop committed
722

723
724
  def _SetFromMinor(self, minor):
    """Set our parameters based on the given minor.
725

726
    This sets our minor variable and our dev_path.
Iustin Pop's avatar
Iustin Pop committed
727
728

    """
729
730
    if minor is None:
      self.minor = self.dev_path = None
731
      self.attached = False
Iustin Pop's avatar
Iustin Pop committed
732
    else:
733
734
      self.minor = minor
      self.dev_path = self._DevPath(minor)
735
      self.attached = True
Iustin Pop's avatar
Iustin Pop committed
736
737

  @staticmethod
738
739
  def _CheckMetaSize(meta_device):
    """Check if the given meta device looks like a valid one.
Iustin Pop's avatar
Iustin Pop committed
740

741
742
    This currently only check the size, which must be around
    128MiB.
Iustin Pop's avatar
Iustin Pop committed
743
744

    """
745
746
    result = utils.RunCmd(["blockdev", "--getsize", meta_device])
    if result.failed:
747
748
      logging.error("Failed to get device size: %s - %s",
                    result.fail_reason, result.output)
749
      return False
Iustin Pop's avatar
Iustin Pop committed
750
    try:
751
752
      sectors = int(result.stdout)
    except ValueError:
753
      logging.error("Invalid output from blockdev: '%s'", result.stdout)
754
755
756
      return False
    bytes = sectors * 512
    if bytes < 128 * 1024 * 1024: # less than 128MiB
757
      logging.error("Meta device too small (%.2fMib)", (bytes / 1024 / 1024))
758
759
      return False
    if bytes > (128 + 32) * 1024 * 1024: # account for an extra (big) PE on LVM
760
      logging.error("Meta device too big (%.2fMiB)", (bytes / 1024 / 1024))
761
762
      return False
    return True
Iustin Pop's avatar
Iustin Pop committed
763

764
765
  def Rename(self, new_id):
    """Rename a device.
Iustin Pop's avatar
Iustin Pop committed
766

767
    This is not supported for drbd devices.
Iustin Pop's avatar
Iustin Pop committed
768
769

    """
770
    raise errors.ProgrammerError("Can't rename a drbd device")
Iustin Pop's avatar
Iustin Pop committed
771

Iustin Pop's avatar
Iustin Pop committed
772

773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
class DRBD8(BaseDRBD):
  """DRBD v8.x block device.

  This implements the local host part of the DRBD device, i.e. it
  doesn't do anything to the supposed peer. If you need a fully
  connected DRBD pair, you need to use this class on both hosts.

  The unique_id for the drbd device is the (local_ip, local_port,
  remote_ip, remote_port) tuple, and it must have two children: the
  data device and the meta_device. The meta device is checked for
  valid size and is zeroed on create.

  """
  _MAX_MINORS = 255
  _PARSE_SHOW = None

  def __init__(self, unique_id, children):
790
791
    if children and children.count(None) > 0:
      children = []
792
793
    super(DRBD8, self).__init__(unique_id, children)
    self.major = self._DRBD_MAJOR
794
795
    version = self._GetVersion()
    if version['k_major'] != 8 :
796
797
      raise errors.BlockDeviceError("Mismatch in DRBD kernel version and"
                                    " requested ganeti usage: kernel is"
798
799
                                    " %s.%s, ganeti wants 8.x" %
                                    (version['k_major'], version['k_minor']))
800

801
    if len(children) not in (0, 2):
802
      raise ValueError("Invalid configuration data %s" % str(children))
803
    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 6:
804
      raise ValueError("Invalid configuration data %s" % str(unique_id))
805
806
    (self._lhost, self._lport,
     self._rhost, self._rport,
807
     self._aminor, self._secret) = unique_id
808
809
810
811
    if (self._lhost is not None and self._lhost == self._rhost and
        self._lport == self._rport):
      raise ValueError("Invalid configuration data, same local/remote %s" %
                       (unique_id,))
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
    self.Attach()

  @classmethod
  def _InitMeta(cls, minor, dev_path):
    """Initialize a meta device.

    This will not work if the given minor is in use.

    """
    result = utils.RunCmd(["drbdmeta", "--force", cls._DevPath(minor),
                           "v08", dev_path, "0", "create-md"])
    if result.failed:
      raise errors.BlockDeviceError("Can't initialize meta device: %s" %
                                    result.output)

  @classmethod
  def _FindUnusedMinor(cls):
    """Find an unused DRBD device.

    This is specific to 8.x as the minors are allocated dynamically,
    so non-existing numbers up to a max minor count are actually free.

    """
    data = cls._GetProcData()

    unused_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
    used_line = re.compile("^ *([0-9]+): cs:")
    highest = None
    for line in data:
      match = unused_line.match(line)
      if match:
        return int(match.group(1))
      match = used_line.match(line)
      if match:
        minor = int(match.group(1))
        highest = max(highest, minor)
    if highest is None: # there are no minors in use at all
      return 0
    if highest >= cls._MAX_MINORS:
851
      logging.error("Error: no free drbd minors!")
852
853
854
855
856
857
858
859
860
861
862
863
864
865
      raise errors.BlockDeviceError("Can't find a free DRBD minor")
    return highest + 1

  @classmethod
  def _IsValidMeta(cls, meta_device):
    """Check if the given meta device looks like a valid one.

    """
    minor = cls._FindUnusedMinor()
    minor_path = cls._DevPath(minor)
    result = utils.RunCmd(["drbdmeta", minor_path,
                           "v08", meta_device, "0",
                           "dstate"])
    if result.failed:
866
      logging.error("Invalid meta device %s: %s", meta_device, result.output)
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
      return False
    return True

  @classmethod
  def _GetShowParser(cls):
    """Return a parser for `drbd show` output.

    This will either create or return an already-create parser for the
    output of the command `drbd show`.

    """
    if cls._PARSE_SHOW is not None:
      return cls._PARSE_SHOW

    # pyparsing setup
    lbrace = pyp.Literal("{").suppress()
    rbrace = pyp.Literal("}").suppress()
    semi = pyp.Literal(";").suppress()
    # this also converts the value to an int
886
    number = pyp.Word(pyp.nums).setParseAction(lambda s, l, t: int(t[0]))
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904

    comment = pyp.Literal ("#") + pyp.Optional(pyp.restOfLine)
    defa = pyp.Literal("_is_default").suppress()
    dbl_quote = pyp.Literal('"').suppress()

    keyword = pyp.Word(pyp.alphanums + '-')

    # value types
    value = pyp.Word(pyp.alphanums + '_-/.:')
    quoted = dbl_quote + pyp.CharsNotIn('"') + dbl_quote
    addr_port = (pyp.Word(pyp.nums + '.') + pyp.Literal(':').suppress() +
                 number)
    # meta device, extended syntax
    meta_value = ((value ^ quoted) + pyp.Literal('[').suppress() +
                  number + pyp.Word(']').suppress())

    # a statement
    stmt = (~rbrace + keyword + ~lbrace +
905
            pyp.Optional(addr_port ^ value ^ quoted ^ meta_value) +
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
            pyp.Optional(defa) + semi +
            pyp.Optional(pyp.restOfLine).suppress())

    # an entire section
    section_name = pyp.Word(pyp.alphas + '_')
    section = section_name + lbrace + pyp.ZeroOrMore(pyp.Group(stmt)) + rbrace

    bnf = pyp.ZeroOrMore(pyp.Group(section ^ stmt))
    bnf.ignore(comment)

    cls._PARSE_SHOW = bnf

    return bnf

  @classmethod
921
922
  def _GetShowData(cls, minor):
    """Return the `drbdsetup show` data for a minor.
923
924
925
926

    """
    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"])
    if result.failed:
927
928
      logging.error("Can't display the drbd config: %s - %s",
                    result.fail_reason, result.output)
929
930
931
932
933
934
935
936
937
938
939
940
941
942
      return None
    return result.stdout

  @classmethod
  def _GetDevInfo(cls, out):
    """Parse details about a given DRBD minor.

    This return, if available, the local backing device (as a path)
    and the local and remote (ip, port) information from a string
    containing the output of the `drbdsetup show` command as returned
    by _GetShowData.

    """
    data = {}
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
    if not out:
      return data

    bnf = cls._GetShowParser()
    # run pyparse

    try:
      results = bnf.parseString(out)
    except pyp.ParseException, err:
      raise errors.BlockDeviceError("Can't parse drbdsetup show output: %s" %
                                    str(err))

    # and massage the results into our desired format
    for section in results:
      sname = section[0]
      if sname == "_this_host":
        for lst in section[1:]:
          if lst[0] == "disk":
            data["local_dev"] = lst[1]
          elif lst[0] == "meta-disk":
            data["meta_dev"] = lst[1]
            data["meta_index"] = lst[2]
          elif lst[0] == "address":
            data["local_addr"] = tuple(lst[1:])
      elif sname == "_remote_host":
        for lst in section[1:]:
          if lst[0] == "address":
            data["remote_addr"] = tuple(lst[1:])
    return data

  def _MatchesLocal(self, info):
    """Test if our local config matches with an existing device.

    The parameter should be as returned from `_GetDevInfo()`. This
    method tests if our local backing device is the same as the one in
    the info parameter, in effect testing if we look like the given
    device.

    """
982
983
984
985
986
    if self._children:
      backend, meta = self._children
    else:
      backend = meta = None

987
    if backend is not None:
988
      retval = ("local_dev" in info and info["local_dev"] == backend.dev_path)
989
990
    else:
      retval = ("local_dev" not in info)
991

992
    if meta is not None:
993
994
995
996
      retval = retval and ("meta_dev" in info and
                           info["meta_dev"] == meta.dev_path)
      retval = retval and ("meta_index" in info and
                           info["meta_index"] == 0)
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
    else:
      retval = retval and ("meta_dev" not in info and
                           "meta_index" not in info)
    return retval

  def _MatchesNet(self, info):
    """Test if our network config matches with an existing device.

    The parameter should be as returned from `_GetDevInfo()`. This
    method tests if our network configuration is the same as the one
    in the info parameter, in effect testing if we look like the given
    device.

    """
    if (((self._lhost is None and not ("local_addr" in info)) and
         (self._rhost is None and not ("remote_addr" in info)))):
      return True

    if self._lhost is None:
      return False

    if not ("local_addr" in info and
            "remote_addr" in info):
      return False

    retval = (info["local_addr"] == (self._lhost, self._lport))
    retval = (retval and
              info["remote_addr"] == (self._rhost, self._rport))
    return retval

  @classmethod
  def _AssembleLocal(cls, minor, backend, meta):
    """Configure the local part of a DRBD device.

    This is the first thing that must be done on an unconfigured DRBD
    device. And it must be done only once.

    """
    if not cls._IsValidMeta(meta):
      return False
1037
1038
1039
    args = ["drbdsetup", cls._DevPath(minor), "disk",
            backend, meta, "0", "-e", "detach", "--create-device"]
    result = utils.RunCmd(args)
1040
    if result.failed:
1041
      logging.error("Can't attach local disk: %s", result.output)
1042
1043
1044
1045
1046
1047
1048
1049
1050
    return not result.failed

  @classmethod
  def _AssembleNet(cls, minor, net_info, protocol,
                   dual_pri=False, hmac=None, secret=None):
    """Configure the network part of the device.

    """
    lhost, lport, rhost, rport = net_info
1051
1052
1053
1054
1055
    if None in net_info:
      # we don't want network connection and actually want to make
      # sure its shutdown
      return cls._ShutdownNet(minor)

1056
    args = ["drbdsetup", cls._DevPath(minor), "net",
1057
1058
1059
            "%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport), protocol,
            "-A", "discard-zero-changes",
            "-B", "consensus",
1060
            "--create-device",
1061
            ]
1062
1063
1064
1065
1066
1067
    if dual_pri:
      args.append("-m")
    if hmac and secret:
      args.extend(["-a", hmac, "-x", secret])
    result = utils.RunCmd(args)
    if result.failed:
1068
1069
      logging.error("Can't setup network for dbrd device: %s - %s",
                    result.fail_reason, result.output)
1070
1071
1072
1073
1074
      return False

    timeout = time.time() + 10
    ok = False
    while time.time() < timeout:
1075
      info = cls._GetDevInfo(cls._GetShowData(minor))
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
      if not "local_addr" in info or not "remote_addr" in info:
        time.sleep(1)
        continue
      if (info["local_addr"] != (lhost, lport) or
          info["remote_addr"] != (rhost, rport)):
        time.sleep(1)
        continue
      ok = True
      break
    if not ok:
1086
      logging.error("Timeout while configuring network")
1087
1088
1089
      return False
    return True

1090
1091
1092
1093
1094
1095
1096
1097
  def AddChildren(self, devices):
    """Add a disk to the DRBD device.

    """
    if self.minor is None:
      raise errors.BlockDeviceError("Can't attach to dbrd8 during AddChildren")
    if len(devices) != 2:
      raise errors.BlockDeviceError("Need two devices for AddChildren")
1098
    info = self._GetDevInfo(self._GetShowData(self.minor))
1099
    if "local_dev" in info:
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
      raise errors.BlockDeviceError("DRBD8 already attached to a local disk")
    backend, meta = devices
    if backend.dev_path is None or meta.dev_path is None:
      raise errors.BlockDeviceError("Children not ready during AddChildren")
    backend.Open()
    meta.Open()
    if not self._CheckMetaSize(meta.dev_path):
      raise errors.BlockDeviceError("Invalid meta device size")
    self._InitMeta(self._FindUnusedMinor(), meta.dev_path)
    if not self._IsValidMeta(meta.dev_path):
      raise errors.BlockDeviceError("Cannot initalize meta device")

    if not self._AssembleLocal(self.minor, backend.dev_path, meta.dev_path):
      raise errors.BlockDeviceError("Can't attach to local storage")
    self._children = devices

  def RemoveChildren(self, devices):
    """Detach the drbd device from local storage.

    """
    if self.minor is None:
      raise errors.BlockDeviceError("Can't attach to drbd8 during"
                                    " RemoveChildren")
1123
    # early return if we don't actually have backing storage
1124
    info = self._GetDevInfo(self._GetShowData(self.minor))
1125
1126
    if "local_dev" not in info:
      return
1127
1128
1129
    if len(self._children) != 2:
      raise errors.BlockDeviceError("We don't have two children: %s" %
                                    self._children)
1130
    if self._children.count(None) == 2: # we don't actually have children :)
1131
      logging.error("Requested detach while detached")
1132
      return
1133
1134
    if len(devices) != 2:
      raise errors.BlockDeviceError("We need two children in RemoveChildren")
1135
1136
1137
1138
1139
    for child, dev in zip(self._children, devices):
      if dev != child.dev_path:
        raise errors.BlockDeviceError("Mismatch in local storage"
                                      " (%s != %s) in RemoveChildren" %
                                      (dev, child.dev_path))
1140
1141
1142
1143
1144

    if not self._ShutdownLocal(self.minor):
      raise errors.BlockDeviceError("Can't detach from local storage")
    self._children = []

1145
1146
1147
1148
1149
1150
  def SetSyncSpeed(self, kbytes):
    """Set the speed of the DRBD syncer.

    """
    children_result = super(DRBD8, self).SetSyncSpeed(kbytes)
    if self.minor is None:
1151
      logging.info("Instance not attached to a device")
1152
1153
1154
1155
      return False
    result = utils.RunCmd(["drbdsetup", self.dev_path, "syncer", "-r", "%d" %
                           kbytes])
    if result.failed:
1156
1157
      logging.error("Can't change syncer rate: %s - %s",
                    result.fail_reason, result.output)
1158
1159
    return not result.failed and children_result

1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
  def GetProcStatus(self):
    """Return device data from /proc.

    """
    if self.minor is None:
      raise errors.BlockDeviceError("GetStats() called while not attached")
    proc_info = self._MassageProcData(self._GetProcData())
    if self.minor not in proc_info:
      raise errors.BlockDeviceError("Can't find myself in /proc (minor %d)" %
                                    self.minor)
    return DRBD8Status(proc_info[self.minor])

1172
1173
1174
1175
1176
1177
  def GetSyncStatus(self):
    """Returns the sync status of the device.


    If sync_percent is None, it means all is ok
    If estimated_time is None, it means we can't esimate
1178
1179
1180
1181
1182
1183
1184
1185
    the time needed, otherwise it's the time left in seconds.


    We set the is_degraded parameter to True on two conditions:
    network not connected or local disk missing.

    We compute the ldisk parameter based on wheter we have a local
    disk or not.
1186

Iustin Pop's avatar
Iustin Pop committed
1187
1188
1189
    @rtype: tuple
    @return: (sync_percent, estimated_time, is_degraded, ldisk)

1190
1191
1192
    """
    if self.minor is None and not self.Attach():
      raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus")
1193
1194
1195
1196
    stats = self.GetProcStatus()
    ldisk = not stats.is_disk_uptodate
    is_degraded = not stats.is_connected
    return stats.sync_percent, stats.est_time, is_degraded or ldisk, ldisk
1197
1198
1199
1200

  def Open(self, force=False):
    """Make the local state primary.

1201
1202
    If the 'force' parameter is given, the '-o' option is passed to
    drbdsetup. Since this is a potentially dangerous operation, the
1203
    force flag should be only given after creation, when it actually
1204
    is mandatory.
1205
1206
1207

    """
    if self.minor is None and not self.Attach():
1208
      logging.error("DRBD cannot attach to a device during open")
1209
1210
1211
1212
1213
1214
      return False
    cmd = ["drbdsetup", self.dev_path, "primary"]
    if force:
      cmd.append("-o")
    result = utils.RunCmd(cmd)
    if result.failed:
1215
      msg = ("Can't make drbd device primary: %s" % result.output)
1216
      logging.error(msg)
1217
      raise errors.BlockDeviceError(msg)
1218
1219
1220
1221
1222
1223
1224
1225

  def Close(self):
    """Make the local state secondary.

    This will, of course, fail if the device is in use.

    """
    if self.minor is None and not self.Attach():
1226
      logging.info("Instance not attached to a device")
1227
1228
1229
      raise errors.BlockDeviceError("Can't find device")
    result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"])
    if result.failed:
1230
1231
      msg = ("Can't switch drbd device to"
             " secondary: %s" % result.output)
1232
      logging.error(msg)
1233
      raise errors.BlockDeviceError(msg)
1234
1235
1236
1237
1238
1239
1240
1241
1242

  def Attach(self):
    """Find a DRBD device which matches our config and attach to it.

    In case of partially attached (local device matches but no network
    setup), we perform the network attach. If successful, we re-test
    the attach if can return success.

    """
Iustin Pop's avatar
Iustin Pop committed
1243
    for minor in (self._aminor,):
1244
      info = self._GetDevInfo(self._GetShowData(minor))
1245
1246
1247
1248
1249
1250
1251
1252
      match_l = self._MatchesLocal(info)
      match_r = self._MatchesNet(info)
      if match_l and match_r:
        break
      if match_l and not match_r and "local_addr" not in info:
        res_r = self._AssembleNet(minor,
                                  (self._lhost, self._lport,
                                   self._rhost, self._rport),
1253
1254
                                  constants.DRBD_NET_PROTOCOL,
                                  hmac=constants.DRBD_HMAC_ALG,
Iustin Pop's avatar
Iustin Pop committed
1255
1256
                                  secret=self._secret
                                  )
1257
1258
1259
        if res_r:
          if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):
            break
1260
1261
1262
1263
      # the weakest case: we find something that is only net attached
      # even though we were passed some children at init time
      if match_r and "local_dev" not in info:
        break
Iustin Pop's avatar
Iustin Pop committed
1264
1265
1266
1267
1268
1269
1270

      # this case must be considered only if we actually have local
      # storage, i.e. not in diskless mode, because all diskless
      # devices are equal from the point of view of local
      # configuration
      if (match_l and "local_dev" in info and
          not match_r and "local_addr" in info):
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
        # strange case - the device network part points to somewhere
        # else, even though its local storage is ours; as we own the
        # drbd space, we try to disconnect from the remote peer and
        # reconnect to our correct one
        if not self._ShutdownNet(minor):
          raise errors.BlockDeviceError("Device has correct local storage,"
                                        " wrong remote peer and is unable to"
                                        " disconnect in order to attach to"
                                        " the correct peer")
        # note: _AssembleNet also handles the case when we don't want
        # local storage (i.e. one or more of the _[lr](host|port) is
        # None)
        if (self._AssembleNet(minor, (self._lhost, self._lport,
1284
1285
                                      self._rhost, self._rport),
                              constants.DRBD_NET_PROTOCOL,
Iustin Pop's avatar
Iustin Pop committed
1286
1287
                              hmac=constants.DRBD_HMAC_ALG,
                              secret=self._secret) and
1288
            self._MatchesNet(self._GetDevInfo(self._GetShowData(minor)))):
1289
1290
          break

1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
    else:
      minor = None

    self._SetFromMinor(minor)
    return minor is not None

  def Assemble(self):
    """Assemble the drbd.

    Method:
      - if we have a local backing device, we bind to it by:
        - checking the list of used drbd devices
        - check if the local minor use of any of them is our own device
        - if yes, abort?
        - if not, bind
      - if we have a local/remote net info:
        - redo the local backing device step for the remote device
        - check if any drbd device is using the local port,
          if yes abort
        - check if any remote drbd device is using the remote
          port, if yes abort (for now)
        - bind our net port
        - bind the remote net port

    """
    self.Attach()
    if self.minor is not None:
1318
      logging.info("Already assembled")
1319
1320
1321
1322
1323
1324
      return True

    result = super(DRBD8, self).Assemble()
    if not result:
      return result

Iustin Pop's avatar
Iustin Pop committed
1325
1326
1327
    # TODO: maybe completely tear-down the minor (drbdsetup ... down)
    # before attaching our own?
    minor = self._aminor
1328
    need_localdev_teardown = False
1329
    if self._children and self._children[0] and self._children[1]:
1330
1331
1332
1333
1334
1335
1336
1337
1338
      result = self._AssembleLocal(minor, self._children[0].dev_path,
                                   self._children[1].dev_path)
      if not result:
        return False
      need_localdev_teardown = True
    if self._lhost and self._lport and self._rhost and self._rport:
      result = self._AssembleNet(minor,
                                 (self._lhost, self._lport,
                                  self._rhost, self._rport),
1339
1340
                                 constants.DRBD_NET_PROTOCOL,
                                 hmac=constants.DRBD_HMAC_ALG,
Iustin Pop's avatar
Iustin Pop committed
1341
                                 secret=self._secret)
1342
1343
1344
      if not result:
        if need_localdev_teardown:
          # we will ignore failures from this
1345
          logging.error("net setup failed, tearing down local device")
1346
1347
1348
1349
1350
          self._ShutdownAll(minor)
        return False
    self._SetFromMinor(minor)
    return True

1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
  @classmethod
  def _ShutdownLocal(cls, minor):
    """Detach from the local device.

    I/Os will continue to be served from the remote device. If we
    don't have a remote device, this operation will fail.

    """
    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"])
    if result.failed:
1361
      logging.error("Can't detach local device: %s", result.output)
1362
1363
    return not result.failed

Iustin Pop's avatar
Iustin Pop committed
1364
1365
1366
1367
1368
1369
1370
1371
  @classmethod
  def _ShutdownNet(cls, minor):
    """Disconnect from the remote peer.

    This fails if we don't have a local device.

    """
    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"])
1372
    if result.failed:
1373
      logging.error("Can't shutdown network: %s", result.output)
Iustin Pop's avatar
Iustin Pop committed
1374
1375
    return not result.failed

1376
1377
1378
1379
1380
1381
1382
1383
1384
  @classmethod
  def _ShutdownAll(cls, minor):
    """Deactivate the device.

    This will, of course, fail if the device is in use.

    """
    result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "down"])
    if result.failed:
1385
      logging.error("Can't shutdown drbd device: %s", result.output)
1386
1387
1388
1389
1390
1391
1392
    return not result.failed

  def Shutdown(self):
    """Shutdown the DRBD device.

    """
    if self.minor is None and not self.Attach():
1393
      logging.info("DRBD device not attached to a device during Shutdown")
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
      return True
    if not self._ShutdownAll(self.minor):
      return False
    self.minor = None
    self.dev_path = None
    return True

  def Remove(self):
    """Stub remove for DRBD devices.

    """
    return self.Shutdown()

  @classmethod
  def Create(cls, unique_id, children, size):
    """Create a new DRBD8 device.

    Since DRBD devices are not created per se, just assembled, this
    function only initializes the metadata.

    """
    if len(children) != 2:
      raise errors.ProgrammerError("Invalid setup for the drbd device")
    meta = children[1]
    meta.Assemble()
    if not meta.Attach():
      raise errors.BlockDeviceError("Can't attach to meta device")
    if not cls._CheckMetaSize(meta.dev_path):
      raise errors.BlockDeviceError("Invalid meta device size")
    cls._InitMeta(cls._FindUnusedMinor(), meta.dev_path)
    if not cls._IsValidMeta(meta.dev_path):
      raise errors.BlockDeviceError("Cannot initalize meta device")
    return cls(unique_id, children)

1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
  def Grow(self, amount):
    """Resize the DRBD device and its backing storage.

    """
    if self.minor is None:
      raise errors.ProgrammerError("drbd8: Grow called while not attached")
    if len(self._children) != 2 or None in self._children:
      raise errors.BlockDeviceError("Cannot grow diskless DRBD8 device")
    self._children[0].Grow(amount)
    result = utils.RunCmd(["drbdsetup", self.dev_path, "resize"])
    if result.failed:
      raise errors.BlockDeviceError("resize failed for %s: %s" %
                                    (self.dev_path, result.output))
    return

Iustin Pop's avatar
Iustin Pop committed
1443

Manuel Franceschini's avatar
Manuel Franceschini committed
1444
1445
class FileStorage(BlockDev):
  """File device.
1446

Manuel Franceschini's avatar
Manuel Franceschini committed
1447
1448
1449
  This class represents the a file storage backend device.

  The unique_id for the file device is a (file_driver, file_path) tuple.
1450

Manuel Franceschini's avatar
Manuel Franceschini committed
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
  """
  def __init__(self, unique_id, children):
    """Initalizes a file device backend.

    """
    if children:
      raise errors.BlockDeviceError("Invalid setup for file device")
    super(FileStorage, self).__init__(unique_id, children)
    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
      raise ValueError("Invalid configuration data %s" % str(unique_id))
    self.driver = unique_id[0]
    self.dev_path = unique_id[1]
Iustin Pop's avatar
Iustin Pop committed
1463
    self.Attach()
Manuel Franceschini's avatar
Manuel Franceschini committed
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503

  def Assemble(self):
    """Assemble the device.

    Checks whether the file device exists, raises BlockDeviceError otherwise.

    """
    if not os.path.exists(self.dev_path):
      raise errors.BlockDeviceError("File device '%s' does not exist." %
                                    self.dev_path)
    return True

  def Shutdown(self):
    """Shutdown the device.

    This is a no-op for the file type, as we don't deacivate
    the file on shutdown.

    """
    return True

  def Open(self, force=False):
    """Make the device ready for I/O.

    This is a no-op for the file type.

    """
    pass

  def Close(self):
    """Notifies that the device will no longer be used for I/O.

    This is a no-op for the file type.

    """
    pass

  def Remove(self):
    """Remove the file backing the block device.

Iustin Pop's avatar
Iustin Pop committed
1504
1505
    @rtype: boolean
    @return: True if the removal was successful
Manuel Franceschini's avatar
Manuel Franceschini committed
1506
1507
1508
1509
1510
1511
1512
1513

    """
    if not os.path.exists(self.dev_path):
      return True
    try:
      os.remove(self.dev_path)
      return True
    except OSError, err:
1514
      logging.error("Can't remove file '%s': %s", self.dev_path, err)