xref: /openbmc/qemu/tests/qemu-iotests/124 (revision d2dfe0b5)
1#!/usr/bin/env python3
2# group: rw backing
3#
4# Tests for incremental drive-backup
5#
6# Copyright (C) 2015 John Snow for Red Hat, Inc.
7#
8# Based on 056.
9#
10# This program is free software; you can redistribute it and/or modify
11# it under the terms of the GNU General Public License as published by
12# the Free Software Foundation; either version 2 of the License, or
13# (at your option) any later version.
14#
15# This program is distributed in the hope that it will be useful,
16# but WITHOUT ANY WARRANTY; without even the implied warranty of
17# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18# GNU General Public License for more details.
19#
20# You should have received a copy of the GNU General Public License
21# along with this program.  If not, see <http://www.gnu.org/licenses/>.
22#
23
24import os
25import iotests
26from iotests import try_remove
27
28
29def io_write_patterns(img, patterns):
30    for pattern in patterns:
31        iotests.qemu_io('-c', 'write -P%s %s %s' % pattern, img)
32
33
34def transaction_action(action, **kwargs):
35    return {
36        'type': action,
37        'data': dict((k.replace('_', '-'), v) for k, v in kwargs.items())
38    }
39
40
41def transaction_bitmap_clear(node, name, **kwargs):
42    return transaction_action('block-dirty-bitmap-clear',
43                              node=node, name=name, **kwargs)
44
45
46def transaction_drive_backup(device, target, **kwargs):
47    return transaction_action('drive-backup', job_id=device, device=device,
48                              target=target, **kwargs)
49
50
51class Bitmap:
52    def __init__(self, name, drive):
53        self.name = name
54        self.drive = drive
55        self.num = 0
56        self.backups = list()
57
58    def base_target(self):
59        return (self.drive['backup'], None)
60
61    def new_target(self, num=None):
62        if num is None:
63            num = self.num
64        self.num = num + 1
65        base = os.path.join(iotests.test_dir,
66                            "%s.%s." % (self.drive['id'], self.name))
67        suff = "%i.%s" % (num, self.drive['fmt'])
68        target = base + "inc" + suff
69        reference = base + "ref" + suff
70        self.backups.append((target, reference))
71        return (target, reference)
72
73    def last_target(self):
74        if self.backups:
75            return self.backups[-1]
76        return self.base_target()
77
78    def del_target(self):
79        for image in self.backups.pop():
80            try_remove(image)
81        self.num -= 1
82
83    def cleanup(self):
84        for backup in self.backups:
85            for image in backup:
86                try_remove(image)
87
88
89class TestIncrementalBackupBase(iotests.QMPTestCase):
90    def __init__(self, *args):
91        super(TestIncrementalBackupBase, self).__init__(*args)
92        self.bitmaps = list()
93        self.files = list()
94        self.drives = list()
95        self.vm = iotests.VM()
96        self.err_img = os.path.join(iotests.test_dir, 'err.%s' % iotests.imgfmt)
97
98
99    def setUp(self):
100        # Create a base image with a distinctive patterning
101        drive0 = self.add_node('drive0')
102        self.img_create(drive0['file'], drive0['fmt'])
103        self.vm.add_drive(drive0['file'], opts='node-name=node0')
104        self.write_default_pattern(drive0['file'])
105        self.vm.launch()
106
107
108    def write_default_pattern(self, target):
109        io_write_patterns(target, (('0x41', 0, 512),
110                                   ('0xd5', '1M', '32k'),
111                                   ('0xdc', '32M', '124k')))
112
113
114    def add_node(self, node_id, fmt=iotests.imgfmt, path=None, backup=None):
115        if path is None:
116            path = os.path.join(iotests.test_dir, '%s.%s' % (node_id, fmt))
117        if backup is None:
118            backup = os.path.join(iotests.test_dir,
119                                  '%s.full.backup.%s' % (node_id, fmt))
120
121        self.drives.append({
122            'id': node_id,
123            'file': path,
124            'backup': backup,
125            'fmt': fmt })
126        return self.drives[-1]
127
128
129    def img_create(self, img, fmt=iotests.imgfmt, size='64M',
130                   parent=None, parentFormat=None, **kwargs):
131        optargs = []
132        for k,v in kwargs.items():
133            optargs = optargs + ['-o', '%s=%s' % (k,v)]
134        args = ['create', '-f', fmt] + optargs + [img, size]
135        if parent:
136            if parentFormat is None:
137                parentFormat = fmt
138            args = args + ['-b', parent, '-F', parentFormat]
139        iotests.qemu_img(*args)
140        self.files.append(img)
141
142
143    def do_qmp_backup(self, error='Input/output error', **kwargs):
144        res = self.vm.qmp('drive-backup', **kwargs)
145        self.assert_qmp(res, 'return', {})
146        return self.wait_qmp_backup(kwargs['device'], error)
147
148
149    def ignore_job_status_change_events(self):
150        while True:
151            e = self.vm.event_wait(name="JOB_STATUS_CHANGE")
152            if e['data']['status'] == 'null':
153                break
154
155    def wait_qmp_backup(self, device, error='Input/output error'):
156        event = self.vm.event_wait(name="BLOCK_JOB_COMPLETED",
157                                   match={'data': {'device': device}})
158        self.assertNotEqual(event, None)
159        self.ignore_job_status_change_events()
160
161        try:
162            failure = self.dictpath(event, 'data/error')
163        except AssertionError:
164            # Backup succeeded.
165            self.assert_qmp(event, 'data/offset', event['data']['len'])
166            return True
167        else:
168            # Backup failed.
169            self.assert_qmp(event, 'data/error', error)
170            return False
171
172
173    def wait_qmp_backup_cancelled(self, device):
174        event = self.vm.event_wait(name='BLOCK_JOB_CANCELLED',
175                                   match={'data': {'device': device}})
176        self.assertNotEqual(event, None)
177        self.ignore_job_status_change_events()
178
179
180    def create_anchor_backup(self, drive=None):
181        if drive is None:
182            drive = self.drives[-1]
183        res = self.do_qmp_backup(job_id=drive['id'],
184                                 device=drive['id'], sync='full',
185                                 format=drive['fmt'], target=drive['backup'])
186        self.assertTrue(res)
187        self.files.append(drive['backup'])
188        return drive['backup']
189
190
191    def make_reference_backup(self, bitmap=None):
192        if bitmap is None:
193            bitmap = self.bitmaps[-1]
194        _, reference = bitmap.last_target()
195        res = self.do_qmp_backup(job_id=bitmap.drive['id'],
196                                 device=bitmap.drive['id'], sync='full',
197                                 format=bitmap.drive['fmt'], target=reference)
198        self.assertTrue(res)
199
200
201    def add_bitmap(self, name, drive, **kwargs):
202        bitmap = Bitmap(name, drive)
203        self.bitmaps.append(bitmap)
204        result = self.vm.qmp('block-dirty-bitmap-add', node=drive['id'],
205                             name=bitmap.name, **kwargs)
206        self.assert_qmp(result, 'return', {})
207        return bitmap
208
209
210    def prepare_backup(self, bitmap=None, parent=None, **kwargs):
211        if bitmap is None:
212            bitmap = self.bitmaps[-1]
213        if parent is None:
214            parent, _ = bitmap.last_target()
215
216        target, _ = bitmap.new_target()
217        self.img_create(target, bitmap.drive['fmt'], parent=parent,
218                        **kwargs)
219        return target
220
221
222    def create_incremental(self, bitmap=None, parent=None,
223                           parentFormat=None, validate=True,
224                           target=None):
225        if bitmap is None:
226            bitmap = self.bitmaps[-1]
227        if parent is None:
228            parent, _ = bitmap.last_target()
229
230        if target is None:
231            target = self.prepare_backup(bitmap, parent)
232        res = self.do_qmp_backup(job_id=bitmap.drive['id'],
233                                 device=bitmap.drive['id'],
234                                 sync='incremental', bitmap=bitmap.name,
235                                 format=bitmap.drive['fmt'], target=target,
236                                 mode='existing')
237        if not res:
238            bitmap.del_target();
239            self.assertFalse(validate)
240        else:
241            self.make_reference_backup(bitmap)
242        return res
243
244
245    def check_backups(self):
246        for bitmap in self.bitmaps:
247            for incremental, reference in bitmap.backups:
248                self.assertTrue(iotests.compare_images(incremental, reference))
249            last = bitmap.last_target()[0]
250            self.assertTrue(iotests.compare_images(last, bitmap.drive['file']))
251
252
253    def hmp_io_writes(self, drive, patterns):
254        for pattern in patterns:
255            self.vm.hmp_qemu_io(drive, 'write -P%s %s %s' % pattern)
256        self.vm.hmp_qemu_io(drive, 'flush')
257
258
259    def do_incremental_simple(self, **kwargs):
260        self.create_anchor_backup()
261        self.add_bitmap('bitmap0', self.drives[0], **kwargs)
262
263        # Sanity: Create a "hollow" incremental backup
264        self.create_incremental()
265        # Three writes: One complete overwrite, one new segment,
266        # and one partial overlap.
267        self.hmp_io_writes(self.drives[0]['id'], (('0xab', 0, 512),
268                                                  ('0xfe', '16M', '256k'),
269                                                  ('0x64', '32736k', '64k')))
270        self.create_incremental()
271        # Three more writes, one of each kind, like above
272        self.hmp_io_writes(self.drives[0]['id'], (('0x9a', 0, 512),
273                                                  ('0x55', '8M', '352k'),
274                                                  ('0x78', '15872k', '1M')))
275        self.create_incremental()
276        self.vm.shutdown()
277        self.check_backups()
278
279
280    def tearDown(self):
281        self.vm.shutdown()
282        for bitmap in self.bitmaps:
283            bitmap.cleanup()
284        for filename in self.files:
285            try_remove(filename)
286
287
288
289class TestIncrementalBackup(TestIncrementalBackupBase):
290    def test_incremental_simple(self):
291        '''
292        Test: Create and verify three incremental backups.
293
294        Create a bitmap and a full backup before VM execution begins,
295        then create a series of three incremental backups "during execution,"
296        i.e.; after IO requests begin modifying the drive.
297        '''
298        return self.do_incremental_simple()
299
300
301    def test_small_granularity(self):
302        '''
303        Test: Create and verify backups made with a small granularity bitmap.
304
305        Perform the same test as test_incremental_simple, but with a granularity
306        of only 32KiB instead of the present default of 64KiB.
307        '''
308        return self.do_incremental_simple(granularity=32768)
309
310
311    def test_large_granularity(self):
312        '''
313        Test: Create and verify backups made with a large granularity bitmap.
314
315        Perform the same test as test_incremental_simple, but with a granularity
316        of 128KiB instead of the present default of 64KiB.
317        '''
318        return self.do_incremental_simple(granularity=131072)
319
320
321    def test_larger_cluster_target(self):
322        '''
323        Test: Create and verify backups made to a larger cluster size target.
324
325        With a default granularity of 64KiB, verify that backups made to a
326        larger cluster size target of 128KiB without a backing file works.
327        '''
328        drive0 = self.drives[0]
329
330        # Create a cluster_size=128k full backup / "anchor" backup
331        self.img_create(drive0['backup'], cluster_size='128k')
332        self.assertTrue(self.do_qmp_backup(device=drive0['id'], sync='full',
333                                           format=drive0['fmt'],
334                                           target=drive0['backup'],
335                                           mode='existing'))
336
337        # Create bitmap and dirty it with some new writes.
338        # overwrite [32736, 32799] which will dirty bitmap clusters at
339        # 32M-64K and 32M. 32M+64K will be left undirtied.
340        bitmap0 = self.add_bitmap('bitmap0', drive0)
341        self.hmp_io_writes(drive0['id'],
342                           (('0xab', 0, 512),
343                            ('0xfe', '16M', '256k'),
344                            ('0x64', '32736k', '64k')))
345        # Check the dirty bitmap stats
346        self.assertTrue(self.vm.check_bitmap_status(
347            'node0', bitmap0.name, {
348                'name': 'bitmap0',
349                'count': 458752,
350                'granularity': 65536,
351                'persistent': False
352            }))
353
354        # Prepare a cluster_size=128k backup target without a backing file.
355        (target, _) = bitmap0.new_target()
356        self.img_create(target, bitmap0.drive['fmt'], cluster_size='128k')
357
358        # Perform Incremental Backup
359        self.assertTrue(self.do_qmp_backup(device=bitmap0.drive['id'],
360                                           sync='incremental',
361                                           bitmap=bitmap0.name,
362                                           format=bitmap0.drive['fmt'],
363                                           target=target,
364                                           mode='existing'))
365        self.make_reference_backup(bitmap0)
366
367        # Add the backing file, then compare and exit.
368        iotests.qemu_img('rebase', '-f', drive0['fmt'], '-u', '-b',
369                         drive0['backup'], '-F', drive0['fmt'], target)
370        self.vm.shutdown()
371        self.check_backups()
372
373
374    def test_incremental_transaction(self):
375        '''Test: Verify backups made from transactionally created bitmaps.
376
377        Create a bitmap "before" VM execution begins, then create a second
378        bitmap AFTER writes have already occurred. Use transactions to create
379        a full backup and synchronize both bitmaps to this backup.
380        Create an incremental backup through both bitmaps and verify that
381        both backups match the current drive0 image.
382        '''
383
384        drive0 = self.drives[0]
385        bitmap0 = self.add_bitmap('bitmap0', drive0)
386        self.hmp_io_writes(drive0['id'], (('0xab', 0, 512),
387                                          ('0xfe', '16M', '256k'),
388                                          ('0x64', '32736k', '64k')))
389        bitmap1 = self.add_bitmap('bitmap1', drive0)
390
391        result = self.vm.qmp('transaction', actions=[
392            transaction_bitmap_clear(bitmap0.drive['id'], bitmap0.name),
393            transaction_bitmap_clear(bitmap1.drive['id'], bitmap1.name),
394            transaction_drive_backup(drive0['id'], drive0['backup'],
395                                     sync='full', format=drive0['fmt'])
396        ])
397        self.assert_qmp(result, 'return', {})
398        self.wait_until_completed(drive0['id'])
399        self.files.append(drive0['backup'])
400
401        self.hmp_io_writes(drive0['id'], (('0x9a', 0, 512),
402                                          ('0x55', '8M', '352k'),
403                                          ('0x78', '15872k', '1M')))
404        # Both bitmaps should be correctly in sync.
405        self.create_incremental(bitmap0)
406        self.create_incremental(bitmap1)
407        self.vm.shutdown()
408        self.check_backups()
409
410
411    def do_transaction_failure_test(self, race=False):
412        # Create a second drive, with pattern:
413        drive1 = self.add_node('drive1')
414        self.img_create(drive1['file'], drive1['fmt'])
415        io_write_patterns(drive1['file'], (('0x14', 0, 512),
416                                           ('0x5d', '1M', '32k'),
417                                           ('0xcd', '32M', '124k')))
418
419        # Create a blkdebug interface to this img as 'drive1'
420        result = self.vm.qmp('blockdev-add',
421            node_name=drive1['id'],
422            driver=drive1['fmt'],
423            file={
424                'driver': 'blkdebug',
425                'image': {
426                    'driver': 'file',
427                    'filename': drive1['file']
428                },
429                'set-state': [{
430                    'event': 'flush_to_disk',
431                    'state': 1,
432                    'new_state': 2
433                }],
434                'inject-error': [{
435                    'event': 'read_aio',
436                    'errno': 5,
437                    'state': 2,
438                    'immediately': False,
439                    'once': True
440                }],
441            }
442        )
443        self.assert_qmp(result, 'return', {})
444
445        # Create bitmaps and full backups for both drives
446        drive0 = self.drives[0]
447        dr0bm0 = self.add_bitmap('bitmap0', drive0)
448        dr1bm0 = self.add_bitmap('bitmap0', drive1)
449        self.create_anchor_backup(drive0)
450        self.create_anchor_backup(drive1)
451        self.assert_no_active_block_jobs()
452        self.assertFalse(self.vm.get_qmp_events(wait=False))
453
454        # Emulate some writes
455        if not race:
456            self.hmp_io_writes(drive0['id'], (('0xab', 0, 512),
457                                              ('0xfe', '16M', '256k'),
458                                              ('0x64', '32736k', '64k')))
459        self.hmp_io_writes(drive1['id'], (('0xba', 0, 512),
460                                          ('0xef', '16M', '256k'),
461                                          ('0x46', '32736k', '64k')))
462
463        # Create incremental backup targets
464        target0 = self.prepare_backup(dr0bm0)
465        target1 = self.prepare_backup(dr1bm0)
466
467        # Ask for a new incremental backup per-each drive,
468        # expecting drive1's backup to fail. In the 'race' test,
469        # we expect drive1 to attempt to cancel the empty drive0 job.
470        transaction = [
471            transaction_drive_backup(drive0['id'], target0, sync='incremental',
472                                     format=drive0['fmt'], mode='existing',
473                                     bitmap=dr0bm0.name),
474            transaction_drive_backup(drive1['id'], target1, sync='incremental',
475                                     format=drive1['fmt'], mode='existing',
476                                     bitmap=dr1bm0.name)
477        ]
478        result = self.vm.qmp('transaction', actions=transaction,
479                             properties={'completion-mode': 'grouped'} )
480        self.assert_qmp(result, 'return', {})
481
482        # Observe that drive0's backup is cancelled and drive1 completes with
483        # an error.
484        self.wait_qmp_backup_cancelled(drive0['id'])
485        self.assertFalse(self.wait_qmp_backup(drive1['id']))
486        error = self.vm.event_wait('BLOCK_JOB_ERROR')
487        self.assert_qmp(error, 'data', {'device': drive1['id'],
488                                        'action': 'report',
489                                        'operation': 'read'})
490        self.assertFalse(self.vm.get_qmp_events(wait=False))
491        self.assert_no_active_block_jobs()
492
493        # Delete drive0's successful target and eliminate our record of the
494        # unsuccessful drive1 target.
495        dr0bm0.del_target()
496        dr1bm0.del_target()
497        if race:
498            # Don't re-run the transaction, we only wanted to test the race.
499            self.vm.shutdown()
500            return
501
502        # Re-run the same transaction:
503        target0 = self.prepare_backup(dr0bm0)
504        target1 = self.prepare_backup(dr1bm0)
505
506        # Re-run the exact same transaction.
507        result = self.vm.qmp('transaction', actions=transaction,
508                             properties={'completion-mode':'grouped'})
509        self.assert_qmp(result, 'return', {})
510
511        # Both should complete successfully this time.
512        self.assertTrue(self.wait_qmp_backup(drive0['id']))
513        self.assertTrue(self.wait_qmp_backup(drive1['id']))
514        self.make_reference_backup(dr0bm0)
515        self.make_reference_backup(dr1bm0)
516        self.assertFalse(self.vm.get_qmp_events(wait=False))
517        self.assert_no_active_block_jobs()
518
519        # And the images should of course validate.
520        self.vm.shutdown()
521        self.check_backups()
522
523    def test_transaction_failure(self):
524        '''Test: Verify backups made from a transaction that partially fails.
525
526        Add a second drive with its own unique pattern, and add a bitmap to each
527        drive. Use blkdebug to interfere with the backup on just one drive and
528        attempt to create a coherent incremental backup across both drives.
529
530        verify a failure in one but not both, then delete the failed stubs and
531        re-run the same transaction.
532
533        verify that both incrementals are created successfully.
534        '''
535        self.do_transaction_failure_test()
536
537    def test_transaction_failure_race(self):
538        '''Test: Verify that transactions with jobs that have no data to
539        transfer do not cause race conditions in the cancellation of the entire
540        transaction job group.
541        '''
542        self.do_transaction_failure_test(race=True)
543
544
545    def test_sync_dirty_bitmap_missing(self):
546        self.assert_no_active_block_jobs()
547        self.files.append(self.err_img)
548        result = self.vm.qmp('drive-backup', device=self.drives[0]['id'],
549                             sync='incremental', format=self.drives[0]['fmt'],
550                             target=self.err_img)
551        self.assert_qmp(result, 'error/class', 'GenericError')
552
553
554    def test_sync_dirty_bitmap_not_found(self):
555        self.assert_no_active_block_jobs()
556        self.files.append(self.err_img)
557        result = self.vm.qmp('drive-backup', device=self.drives[0]['id'],
558                             sync='incremental', bitmap='unknown',
559                             format=self.drives[0]['fmt'], target=self.err_img)
560        self.assert_qmp(result, 'error/class', 'GenericError')
561
562
563    def test_sync_dirty_bitmap_bad_granularity(self):
564        '''
565        Test: Test what happens if we provide an improper granularity.
566
567        The granularity must always be a power of 2.
568        '''
569        self.assert_no_active_block_jobs()
570        self.assertRaises(AssertionError, self.add_bitmap,
571                          'bitmap0', self.drives[0],
572                          granularity=64000)
573
574    def test_growing_before_backup(self):
575        '''
576        Test: Add a bitmap, truncate the image, write past the old
577              end, do a backup.
578
579        Incremental backup should not ignore dirty bits past the old
580        image end.
581        '''
582        self.assert_no_active_block_jobs()
583
584        self.create_anchor_backup()
585
586        self.add_bitmap('bitmap0', self.drives[0])
587
588        res = self.vm.qmp('block_resize', device=self.drives[0]['id'],
589                          size=(65 * 1048576))
590        self.assert_qmp(res, 'return', {})
591
592        # Dirty the image past the old end
593        self.vm.hmp_qemu_io(self.drives[0]['id'], 'write 64M 64k')
594
595        target = self.prepare_backup(size='65M')
596        self.create_incremental(target=target)
597
598        self.vm.shutdown()
599        self.check_backups()
600
601
602class TestIncrementalBackupBlkdebug(TestIncrementalBackupBase):
603    '''Incremental backup tests that utilize a BlkDebug filter on drive0.'''
604
605    def setUp(self):
606        drive0 = self.add_node('drive0')
607        self.img_create(drive0['file'], drive0['fmt'])
608        self.write_default_pattern(drive0['file'])
609        self.vm.launch()
610
611    def test_incremental_failure(self):
612        '''Test: Verify backups made after a failure are correct.
613
614        Simulate a failure during an incremental backup block job,
615        emulate additional writes, then create another incremental backup
616        afterwards and verify that the backup created is correct.
617        '''
618
619        drive0 = self.drives[0]
620        result = self.vm.qmp('blockdev-add',
621            node_name=drive0['id'],
622            driver=drive0['fmt'],
623            file={
624                'driver': 'blkdebug',
625                'image': {
626                    'driver': 'file',
627                    'filename': drive0['file']
628                },
629                'set-state': [{
630                    'event': 'flush_to_disk',
631                    'state': 1,
632                    'new_state': 2
633                }],
634                'inject-error': [{
635                    'event': 'read_aio',
636                    'errno': 5,
637                    'state': 2,
638                    'immediately': False,
639                    'once': True
640                }],
641            }
642        )
643        self.assert_qmp(result, 'return', {})
644
645        self.create_anchor_backup(drive0)
646        self.add_bitmap('bitmap0', drive0)
647        # Note: at this point, during a normal execution,
648        # Assume that the VM resumes and begins issuing IO requests here.
649
650        self.hmp_io_writes(drive0['id'], (('0xab', 0, 512),
651                                          ('0xfe', '16M', '256k'),
652                                          ('0x64', '32736k', '64k')))
653
654        result = self.create_incremental(validate=False)
655        self.assertFalse(result)
656        self.hmp_io_writes(drive0['id'], (('0x9a', 0, 512),
657                                          ('0x55', '8M', '352k'),
658                                          ('0x78', '15872k', '1M')))
659        self.create_incremental()
660        self.vm.shutdown()
661        self.check_backups()
662
663    def test_incremental_pause(self):
664        """
665        Test an incremental backup that errors into a pause and is resumed.
666        """
667
668        drive0 = self.drives[0]
669        # NB: The blkdebug script here looks for a "flush, read" pattern.
670        # The flush occurs in hmp_io_writes, and the read during the block job.
671        result = self.vm.qmp('blockdev-add',
672                             node_name=drive0['id'],
673                             driver=drive0['fmt'],
674                             file={
675                                 'driver': 'blkdebug',
676                                 'image': {
677                                     'driver': 'file',
678                                     'filename': drive0['file']
679                                 },
680                                 'set-state': [{
681                                     'event': 'flush_to_disk',
682                                     'state': 1,
683                                     'new_state': 2
684                                 }],
685                                 'inject-error': [{
686                                     'event': 'read_aio',
687                                     'errno': 5,
688                                     'state': 2,
689                                     'immediately': False,
690                                     'once': True
691                                 }],
692                             })
693        self.assert_qmp(result, 'return', {})
694        self.create_anchor_backup(drive0)
695        bitmap = self.add_bitmap('bitmap0', drive0)
696
697        # Emulate guest activity
698        self.hmp_io_writes(drive0['id'], (('0xab', 0, 512),
699                                          ('0xfe', '16M', '256k'),
700                                          ('0x64', '32736k', '64k')))
701
702        # Bitmap Status Check
703        self.assertTrue(self.vm.check_bitmap_status(
704            drive0['id'], bitmap.name, {
705                'count': 458752,
706                'granularity': 65536,
707                'busy': False,
708                'recording': True
709            }))
710
711        # Start backup
712        parent, _ = bitmap.last_target()
713        target = self.prepare_backup(bitmap, parent)
714        res = self.vm.qmp('drive-backup',
715                          job_id=bitmap.drive['id'],
716                          device=bitmap.drive['id'],
717                          sync='incremental',
718                          bitmap=bitmap.name,
719                          format=bitmap.drive['fmt'],
720                          target=target,
721                          mode='existing',
722                          on_source_error='stop')
723        self.assert_qmp(res, 'return', {})
724
725        # Wait for the error
726        event = self.vm.event_wait(name="BLOCK_JOB_ERROR",
727                                   match={"data":{"device":bitmap.drive['id']}})
728        self.assert_qmp(event, 'data', {'device': bitmap.drive['id'],
729                                        'action': 'stop',
730                                        'operation': 'read'})
731
732        # Bitmap Status Check
733        self.assertTrue(self.vm.check_bitmap_status(
734            drive0['id'], bitmap.name, {
735                'count': 458752,
736                'granularity': 65536,
737                'busy': True,
738                'recording': True
739            }))
740
741        # Resume and check incremental backup for consistency
742        res = self.vm.qmp('block-job-resume', device=bitmap.drive['id'])
743        self.assert_qmp(res, 'return', {})
744        self.wait_qmp_backup(bitmap.drive['id'])
745
746        # Bitmap Status Check
747        self.assertTrue(self.vm.check_bitmap_status(
748            drive0['id'], bitmap.name, {
749                'count': 0,
750                'granularity': 65536,
751                'busy': False,
752                'recording': True
753            }))
754
755        # Finalize / Cleanup
756        self.make_reference_backup(bitmap)
757        self.vm.shutdown()
758        self.check_backups()
759
760
761if __name__ == '__main__':
762    iotests.main(supported_fmts=['qcow2'],
763                 supported_protocols=['file'])
764