Coverage for drivers/linstorvhdutil.py : 21%

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1#!/usr/bin/env python3
2#
3# Copyright (C) 2020 Vates SAS - ronan.abhamon@vates.fr
4#
5# This program is free software: you can redistribute it and/or modify
6# it under the terms of the GNU General Public License as published by
7# the Free Software Foundation, either version 3 of the License, or
8# (at your option) any later version.
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 General Public License for more details.
13#
14# You should have received a copy of the GNU General Public License
15# along with this program. If not, see <https://www.gnu.org/licenses/>.
17from sm_typing import override
19from linstorjournaler import LinstorJournaler
20from linstorvolumemanager import LinstorVolumeManager
21import base64
22import errno
23import json
24import socket
25import time
26import util
27import vhdutil
28import xs_errors
30MANAGER_PLUGIN = 'linstor-manager'
33def call_remote_method(session, host_ref, method, device_path, args):
34 try:
35 response = session.xenapi.host.call_plugin(
36 host_ref, MANAGER_PLUGIN, method, args
37 )
38 except Exception as e:
39 util.SMlog('call-plugin ({} with {}) exception: {}'.format(
40 method, args, e
41 ))
42 raise util.SMException(str(e))
44 util.SMlog('call-plugin ({} with {}) returned: {}'.format(
45 method, args, response
46 ))
48 return response
51def check_ex(path, ignoreMissingFooter = False, fast = False):
52 cmd = [vhdutil.VHD_UTIL, "check", vhdutil.OPT_LOG_ERR, "-n", path]
53 if ignoreMissingFooter:
54 cmd.append("-i")
55 if fast:
56 cmd.append("-B")
58 vhdutil.ioretry(cmd)
61class LinstorCallException(util.SMException):
62 def __init__(self, cmd_err):
63 self.cmd_err = cmd_err
65 @override
66 def __str__(self) -> str:
67 return str(self.cmd_err)
70class ErofsLinstorCallException(LinstorCallException):
71 pass
74class NoPathLinstorCallException(LinstorCallException):
75 pass
78def linstorhostcall(local_method, remote_method):
79 def decorated(response_parser):
80 def wrapper(*args, **kwargs):
81 self = args[0]
82 vdi_uuid = args[1]
84 device_path = self._linstor.build_device_path(
85 self._linstor.get_volume_name(vdi_uuid)
86 )
88 # A. Try a call using directly the DRBD device to avoid
89 # remote request.
91 # Try to read locally if the device is not in use or if the device
92 # is up to date and not diskless.
93 (node_names, in_use_by) = \
94 self._linstor.find_up_to_date_diskful_nodes(vdi_uuid)
96 local_e = None
97 try:
98 if not in_use_by or socket.gethostname() in node_names:
99 return self._call_local_method(local_method, device_path, *args[2:], **kwargs)
100 except ErofsLinstorCallException as e:
101 local_e = e.cmd_err
102 except Exception as e:
103 local_e = e
105 util.SMlog(
106 'unable to execute `{}` locally, retry using a readable host... (cause: {})'.format(
107 remote_method, local_e if local_e else 'local diskless + in use or not up to date'
108 )
109 )
111 if in_use_by:
112 node_names = {in_use_by}
114 # B. Execute the plugin on master or slave.
115 remote_args = {
116 'devicePath': device_path,
117 'groupName': self._linstor.group_name
118 }
119 remote_args.update(**kwargs)
120 remote_args = {str(key): str(value) for key, value in remote_args.items()}
122 try:
123 def remote_call():
124 host_ref = self._get_readonly_host(vdi_uuid, device_path, node_names)
125 return call_remote_method(self._session, host_ref, remote_method, device_path, remote_args)
126 response = util.retry(remote_call, 5, 2)
127 except Exception as remote_e:
128 self._raise_openers_exception(device_path, local_e or remote_e)
130 return response_parser(self, vdi_uuid, response)
131 return wrapper
132 return decorated
135def linstormodifier():
136 def decorated(func):
137 def wrapper(*args, **kwargs):
138 self = args[0]
140 ret = func(*args, **kwargs)
141 self._linstor.invalidate_resource_cache()
142 return ret
143 return wrapper
144 return decorated
147class LinstorVhdUtil:
148 MAX_SIZE = 2 * 1024 * 1024 * 1024 * 1024 # Max VHD size.
150 def __init__(self, session, linstor):
151 self._session = session
152 self._linstor = linstor
154 def create_chain_paths(self, vdi_uuid, readonly=False):
155 # OPTIMIZE: Add a limit_to_first_allocated_block param to limit vhdutil calls.
156 # Useful for the snapshot code algorithm.
158 leaf_vdi_path = self._linstor.get_device_path(vdi_uuid)
159 path = leaf_vdi_path
160 while True:
161 if not util.pathexists(path):
162 raise xs_errors.XenError(
163 'VDIUnavailable', opterr='Could not find: {}'.format(path)
164 )
166 # Diskless path can be created on the fly, ensure we can open it.
167 def check_volume_usable():
168 while True:
169 try:
170 with open(path, 'r' if readonly else 'r+'):
171 pass
172 except IOError as e:
173 if e.errno == errno.ENODATA:
174 time.sleep(2)
175 continue
176 if e.errno == errno.EROFS:
177 util.SMlog('Volume not attachable because RO. Openers: {}'.format(
178 self._linstor.get_volume_openers(vdi_uuid)
179 ))
180 raise
181 break
182 util.retry(check_volume_usable, 15, 2)
184 vdi_uuid = self.get_vhd_info(vdi_uuid).parentUuid
185 if not vdi_uuid:
186 break
187 path = self._linstor.get_device_path(vdi_uuid)
188 readonly = True # Non-leaf is always readonly.
190 return leaf_vdi_path
192 # --------------------------------------------------------------------------
193 # Getters: read locally and try on another host in case of failure.
194 # --------------------------------------------------------------------------
196 def check(self, vdi_uuid, ignore_missing_footer=False, fast=False):
197 kwargs = {
198 'ignoreMissingFooter': ignore_missing_footer,
199 'fast': fast
200 }
201 try:
202 self._check(vdi_uuid, **kwargs) # pylint: disable = E1123
203 return True
204 except Exception as e:
205 util.SMlog('Call to `check` failed: {}'.format(e))
206 return False
208 @linstorhostcall(check_ex, 'check')
209 def _check(self, vdi_uuid, response):
210 return util.strtobool(response)
212 def get_vhd_info(self, vdi_uuid, include_parent=True):
213 kwargs = {
214 'includeParent': include_parent,
215 'resolveParent': False
216 }
217 # TODO: Replace pylint comment with this feature when possible:
218 # https://github.com/PyCQA/pylint/pull/2926
219 return self._get_vhd_info(vdi_uuid, self._extract_uuid, **kwargs) # pylint: disable = E1123
221 @linstorhostcall(vhdutil.getVHDInfo, 'getVHDInfo')
222 def _get_vhd_info(self, vdi_uuid, response):
223 obj = json.loads(response)
225 vhd_info = vhdutil.VHDInfo(vdi_uuid)
226 vhd_info.sizeVirt = obj['sizeVirt']
227 vhd_info.sizePhys = obj['sizePhys']
228 if 'parentPath' in obj:
229 vhd_info.parentPath = obj['parentPath']
230 vhd_info.parentUuid = obj['parentUuid']
231 vhd_info.hidden = obj['hidden']
232 vhd_info.path = obj['path']
234 return vhd_info
236 @linstorhostcall(vhdutil.hasParent, 'hasParent')
237 def has_parent(self, vdi_uuid, response):
238 return util.strtobool(response)
240 def get_parent(self, vdi_uuid):
241 return self._get_parent(vdi_uuid, self._extract_uuid)
243 @linstorhostcall(vhdutil.getParent, 'getParent')
244 def _get_parent(self, vdi_uuid, response):
245 return response
247 @linstorhostcall(vhdutil.getSizeVirt, 'getSizeVirt')
248 def get_size_virt(self, vdi_uuid, response):
249 return int(response)
251 @linstorhostcall(vhdutil.getSizePhys, 'getSizePhys')
252 def get_size_phys(self, vdi_uuid, response):
253 return int(response)
255 @linstorhostcall(vhdutil.getAllocatedSize, 'getAllocatedSize')
256 def get_allocated_size(self, vdi_uuid, response):
257 return int(response)
259 @linstorhostcall(vhdutil.getDepth, 'getDepth')
260 def get_depth(self, vdi_uuid, response):
261 return int(response)
263 @linstorhostcall(vhdutil.getKeyHash, 'getKeyHash')
264 def get_key_hash(self, vdi_uuid, response):
265 return response or None
267 @linstorhostcall(vhdutil.getBlockBitmap, 'getBlockBitmap')
268 def get_block_bitmap(self, vdi_uuid, response):
269 return base64.b64decode(response)
271 @linstorhostcall('_get_drbd_size', 'getDrbdSize')
272 def get_drbd_size(self, vdi_uuid, response):
273 return int(response)
275 def _get_drbd_size(self, path):
276 (ret, stdout, stderr) = util.doexec(['blockdev', '--getsize64', path])
277 if ret == 0:
278 return int(stdout.strip())
279 raise util.SMException('Failed to get DRBD size: {}'.format(stderr))
281 # --------------------------------------------------------------------------
282 # Setters: only used locally.
283 # --------------------------------------------------------------------------
285 @linstormodifier()
286 def create(self, path, size, static, msize=0):
287 return self._call_local_method_or_fail(vhdutil.create, path, size, static, msize)
289 @linstormodifier()
290 def set_size_virt(self, path, size, jfile):
291 return self._call_local_method_or_fail(vhdutil.setSizeVirt, path, size, jfile)
293 @linstormodifier()
294 def set_size_virt_fast(self, path, size):
295 return self._call_local_method_or_fail(vhdutil.setSizeVirtFast, path, size)
297 @linstormodifier()
298 def set_size_phys(self, path, size, debug=True):
299 return self._call_local_method_or_fail(vhdutil.setSizePhys, path, size, debug)
301 @linstormodifier()
302 def set_parent(self, path, parentPath, parentRaw=False):
303 return self._call_local_method_or_fail(vhdutil.setParent, path, parentPath, parentRaw)
305 @linstormodifier()
306 def set_hidden(self, path, hidden=True):
307 return self._call_local_method_or_fail(vhdutil.setHidden, path, hidden)
309 @linstormodifier()
310 def set_key(self, path, key_hash):
311 return self._call_local_method_or_fail(vhdutil.setKey, path, key_hash)
313 @linstormodifier()
314 def kill_data(self, path):
315 return self._call_local_method_or_fail(vhdutil.killData, path)
317 @linstormodifier()
318 def snapshot(self, path, parent, parentRaw, msize=0, checkEmpty=True):
319 return self._call_local_method_or_fail(vhdutil.snapshot, path, parent, parentRaw, msize, checkEmpty)
321 def inflate(self, journaler, vdi_uuid, vdi_path, new_size, old_size):
322 # Only inflate if the LINSTOR volume capacity is not enough.
323 new_size = LinstorVolumeManager.round_up_volume_size(new_size)
324 if new_size <= old_size:
325 return
327 util.SMlog(
328 'Inflate {} (size={}, previous={})'
329 .format(vdi_path, new_size, old_size)
330 )
332 journaler.create(
333 LinstorJournaler.INFLATE, vdi_uuid, old_size
334 )
335 self._linstor.resize_volume(vdi_uuid, new_size)
337 # TODO: Replace pylint comment with this feature when possible:
338 # https://github.com/PyCQA/pylint/pull/2926
339 result_size = self.get_drbd_size(vdi_uuid) # pylint: disable = E1120
340 if result_size < new_size:
341 util.SMlog(
342 'WARNING: Cannot inflate volume to {}B, result size: {}B'
343 .format(new_size, result_size)
344 )
346 self._zeroize(vdi_path, result_size - vhdutil.VHD_FOOTER_SIZE)
347 self.set_size_phys(vdi_path, result_size, False)
348 journaler.remove(LinstorJournaler.INFLATE, vdi_uuid)
350 def deflate(self, vdi_path, new_size, old_size, zeroize=False):
351 if zeroize:
352 assert old_size > vhdutil.VHD_FOOTER_SIZE
353 self._zeroize(vdi_path, old_size - vhdutil.VHD_FOOTER_SIZE)
355 new_size = LinstorVolumeManager.round_up_volume_size(new_size)
356 if new_size >= old_size:
357 return
359 util.SMlog(
360 'Deflate {} (new size={}, previous={})'
361 .format(vdi_path, new_size, old_size)
362 )
364 self.set_size_phys(vdi_path, new_size)
365 # TODO: Change the LINSTOR volume size using linstor.resize_volume.
367 # --------------------------------------------------------------------------
368 # Remote setters: write locally and try on another host in case of failure.
369 # --------------------------------------------------------------------------
371 @linstormodifier()
372 def force_parent(self, path, parentPath, parentRaw=False):
373 kwargs = {
374 'parentPath': str(parentPath),
375 'parentRaw': parentRaw
376 }
377 return self._call_method(vhdutil.setParent, 'setParent', path, use_parent=False, **kwargs)
379 @linstormodifier()
380 def force_coalesce(self, path):
381 return int(self._call_method(vhdutil.coalesce, 'coalesce', path, use_parent=True))
383 @linstormodifier()
384 def force_repair(self, path):
385 return self._call_method(vhdutil.repair, 'repair', path, use_parent=False)
387 @linstormodifier()
388 def force_deflate(self, path, newSize, oldSize, zeroize):
389 kwargs = {
390 'newSize': newSize,
391 'oldSize': oldSize,
392 'zeroize': zeroize
393 }
394 return self._call_method('_force_deflate', 'deflate', path, use_parent=False, **kwargs)
396 def _force_deflate(self, path, newSize, oldSize, zeroize):
397 self.deflate(path, newSize, oldSize, zeroize)
399 # --------------------------------------------------------------------------
400 # Static helpers.
401 # --------------------------------------------------------------------------
403 @classmethod
404 def compute_volume_size(cls, virtual_size, image_type):
405 if image_type == vhdutil.VDI_TYPE_VHD:
406 # All LINSTOR VDIs have the metadata area preallocated for
407 # the maximum possible virtual size (for fast online VDI.resize).
408 meta_overhead = vhdutil.calcOverheadEmpty(cls.MAX_SIZE)
409 bitmap_overhead = vhdutil.calcOverheadBitmap(virtual_size)
410 virtual_size += meta_overhead + bitmap_overhead
411 elif image_type != vhdutil.VDI_TYPE_RAW:
412 raise Exception('Invalid image type: {}'.format(image_type))
414 return LinstorVolumeManager.round_up_volume_size(virtual_size)
416 # --------------------------------------------------------------------------
417 # Helpers.
418 # --------------------------------------------------------------------------
420 def _extract_uuid(self, device_path):
421 # TODO: Remove new line in the vhdutil module. Not here.
422 return self._linstor.get_volume_uuid_from_device_path(
423 device_path.rstrip('\n')
424 )
426 def _get_readonly_host(self, vdi_uuid, device_path, node_names):
427 """
428 When vhd-util is called to fetch VDI info we must find a
429 diskful DRBD disk to read the data. It's the goal of this function.
430 Why? Because when a VHD is open in RO mode, the LVM layer is used
431 directly to bypass DRBD verifications (we can have only one process
432 that reads/writes to disk with DRBD devices).
433 """
435 if not node_names:
436 raise xs_errors.XenError(
437 'VDIUnavailable',
438 opterr='Unable to find diskful node: {} (path={})'
439 .format(vdi_uuid, device_path)
440 )
442 hosts = self._session.xenapi.host.get_all_records()
443 for host_ref, host_record in hosts.items():
444 if host_record['hostname'] in node_names:
445 return host_ref
447 raise xs_errors.XenError(
448 'VDIUnavailable',
449 opterr='Unable to find a valid host from VDI: {} (path={})'
450 .format(vdi_uuid, device_path)
451 )
453 # --------------------------------------------------------------------------
455 def _raise_openers_exception(self, device_path, e):
456 if isinstance(e, util.CommandException):
457 e_str = 'cmd: `{}`, code: `{}`, reason: `{}`'.format(e.cmd, e.code, e.reason)
458 else:
459 e_str = str(e)
461 try:
462 volume_uuid = self._linstor.get_volume_uuid_from_device_path(
463 device_path
464 )
465 e_wrapper = Exception(
466 e_str + ' (openers: {})'.format(
467 self._linstor.get_volume_openers(volume_uuid)
468 )
469 )
470 except Exception as illformed_e:
471 e_wrapper = Exception(
472 e_str + ' (unable to get openers: {})'.format(illformed_e)
473 )
474 util.SMlog('raise opener exception: {}'.format(e_wrapper))
475 raise e_wrapper # pylint: disable = E0702
477 def _call_local_method(self, local_method, device_path, *args, **kwargs):
478 if isinstance(local_method, str):
479 local_method = getattr(self, local_method)
481 try:
482 def local_call():
483 try:
484 return local_method(device_path, *args, **kwargs)
485 except util.CommandException as e:
486 if e.code == errno.EROFS or e.code == errno.EMEDIUMTYPE:
487 raise ErofsLinstorCallException(e) # Break retry calls.
488 if e.code == errno.ENOENT:
489 raise NoPathLinstorCallException(e)
490 raise e
491 # Retry only locally if it's not an EROFS exception.
492 return util.retry(local_call, 5, 2, exceptions=[util.CommandException])
493 except util.CommandException as e:
494 util.SMlog('failed to execute locally vhd-util (sys {})'.format(e.code))
495 raise e
497 def _call_local_method_or_fail(self, local_method, device_path, *args, **kwargs):
498 try:
499 return self._call_local_method(local_method, device_path, *args, **kwargs)
500 except ErofsLinstorCallException as e:
501 # Volume is locked on a host, find openers.
502 self._raise_openers_exception(device_path, e.cmd_err)
504 def _call_method(self, local_method, remote_method, device_path, use_parent, *args, **kwargs):
505 # Note: `use_parent` exists to know if the VHD parent is used by the local/remote method.
506 # Normally in case of failure, if the parent is unused we try to execute the method on
507 # another host using the DRBD opener list. In the other case, if the parent is required,
508 # we must check where this last one is open instead of the child.
510 if isinstance(local_method, str):
511 local_method = getattr(self, local_method)
513 # A. Try to write locally...
514 try:
515 return self._call_local_method(local_method, device_path, *args, **kwargs)
516 except Exception:
517 pass
519 util.SMlog('unable to execute `{}` locally, retry using a writable host...'.format(remote_method))
521 # B. Execute the command on another host.
522 # B.1. Get host list.
523 try:
524 hosts = self._session.xenapi.host.get_all_records()
525 except Exception as e:
526 raise xs_errors.XenError(
527 'VDIUnavailable',
528 opterr='Unable to get host list to run vhd-util command `{}` (path={}): {}'
529 .format(remote_method, device_path, e)
530 )
532 # B.2. Prepare remote args.
533 remote_args = {
534 'devicePath': device_path,
535 'groupName': self._linstor.group_name
536 }
537 remote_args.update(**kwargs)
538 remote_args = {str(key): str(value) for key, value in remote_args.items()}
540 volume_uuid = self._linstor.get_volume_uuid_from_device_path(
541 device_path
542 )
543 parent_volume_uuid = None
544 if use_parent:
545 parent_volume_uuid = self.get_parent(volume_uuid)
547 openers_uuid = parent_volume_uuid if use_parent else volume_uuid
549 # B.3. Call!
550 def remote_call():
551 try:
552 all_openers = self._linstor.get_volume_openers(openers_uuid)
553 except Exception as e:
554 raise xs_errors.XenError(
555 'VDIUnavailable',
556 opterr='Unable to get DRBD openers to run vhd-util command `{}` (path={}): {}'
557 .format(remote_method, device_path, e)
558 )
560 no_host_found = True
561 for hostname, openers in all_openers.items():
562 if not openers:
563 continue
565 try:
566 host_ref = next(ref for ref, rec in hosts.items() if rec['hostname'] == hostname)
567 except StopIteration:
568 continue
570 no_host_found = False
571 try:
572 return call_remote_method(self._session, host_ref, remote_method, device_path, remote_args)
573 except Exception:
574 pass
576 if no_host_found:
577 try:
578 return local_method(device_path, *args, **kwargs)
579 except Exception as e:
580 self._raise_openers_exception(device_path, e)
582 raise xs_errors.XenError(
583 'VDIUnavailable',
584 opterr='No valid host found to run vhd-util command `{}` (path=`{}`, openers=`{}`)'
585 .format(remote_method, device_path, openers)
586 )
587 return util.retry(remote_call, 5, 2)
589 @staticmethod
590 def _zeroize(path, size):
591 if not util.zeroOut(path, size, vhdutil.VHD_FOOTER_SIZE):
592 raise xs_errors.XenError(
593 'EIO',
594 opterr='Failed to zero out VHD footer {}'.format(path)
595 )