xref: /qemu/tests/qemu-iotests/tests/copy-before-write (revision b6aed193)

#!/usr/bin/env python3
# group: auto backup
#
# Copyright (c) 2022 Virtuozzo International GmbH
#
# 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, see <http://www.gnu.org/licenses/>.
#

import os
import re

from qemu.machine import QEMUMachine

import iotests
from iotests import qemu_img_create, qemu_io


temp_img = os.path.join(iotests.test_dir, 'temp')
source_img = os.path.join(iotests.test_dir, 'source')
size = '1M'


class TestCbwError(iotests.QMPTestCase):
    def tearDown(self):
        self.vm.shutdown()
        os.remove(temp_img)
        os.remove(source_img)

    def setUp(self):
        qemu_img_create('-f', iotests.imgfmt, source_img, size)
        qemu_img_create('-f', iotests.imgfmt, temp_img, size)
        qemu_io('-c', 'write 0 1M', source_img)

        opts = ['-nodefaults', '-display', 'none', '-machine', 'none']
        self.vm = QEMUMachine(iotests.qemu_prog, opts,
                              base_temp_dir=iotests.test_dir)
        self.vm.launch()

    def do_cbw_error(self, on_cbw_error):
        self.vm.cmd('blockdev-add', {
            'node-name': 'cbw',
            'driver': 'copy-before-write',
            'on-cbw-error': on_cbw_error,
            'file': {
                'driver': iotests.imgfmt,
                'file': {
                    'driver': 'file',
                    'filename': source_img,
                }
            },
            'target': {
                'driver': iotests.imgfmt,
                'file': {
                    'driver': 'blkdebug',
                    'image': {
                        'driver': 'file',
                        'filename': temp_img
                    },
                    'inject-error': [
                        {
                            'event': 'write_aio',
                            'errno': 5,
                            'immediately': False,
                            'once': True
                        }
                    ]
                }
            }
        })

        self.vm.cmd('blockdev-add', {
            'node-name': 'access',
            'driver': 'snapshot-access',
            'file': 'cbw'
        })

        result = self.vm.qmp('human-monitor-command',
                             command_line='qemu-io cbw "write 0 1M"')
        self.assert_qmp(result, 'return', '')

        result = self.vm.qmp('human-monitor-command',
                             command_line='qemu-io access "read 0 1M"')
        self.assert_qmp(result, 'return', '')

        self.vm.shutdown()
        log = self.vm.get_log()
        log = re.sub(r'^\[I \d+\.\d+\] OPENED\n', '', log)
        log = re.sub(r'\[I \+\d+\.\d+\] CLOSED\n?$', '', log)
        log = iotests.filter_qemu_io(log)
        return log

    def test_break_snapshot_on_cbw_error(self):
        """break-snapshot behavior:
        Guest write succeed, but further snapshot-read fails, as snapshot is
        broken.
        """
        log = self.do_cbw_error('break-snapshot')

        self.assertEqual(log, """\
wrote 1048576/1048576 bytes at offset 0
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
read failed: Permission denied
""")

    def test_break_guest_write_on_cbw_error(self):
        """break-guest-write behavior:
        Guest write fails, but snapshot-access continues working and further
        snapshot-read succeeds.
        """
        log = self.do_cbw_error('break-guest-write')

        self.assertEqual(log, """\
write failed: Input/output error
read 1048576/1048576 bytes at offset 0
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
""")

    def do_cbw_timeout(self, on_cbw_error):
        self.vm.cmd('object-add', {
            'qom-type': 'throttle-group',
            'id': 'group0',
            'limits': {'bps-write': 300 * 1024}
        })

        self.vm.cmd('blockdev-add', {
            'node-name': 'cbw',
            'driver': 'copy-before-write',
            'on-cbw-error': on_cbw_error,
            'cbw-timeout': 1,
            'file': {
                'driver': iotests.imgfmt,
                'file': {
                    'driver': 'file',
                    'filename': source_img,
                }
            },
            'target': {
                'driver': 'throttle',
                'throttle-group': 'group0',
                'file': {
                    'driver': 'qcow2',
                    'file': {
                        'driver': 'file',
                        'filename': temp_img
                    }
                }
            }
        })

        self.vm.cmd('blockdev-add', {
            'node-name': 'access',
            'driver': 'snapshot-access',
            'file': 'cbw'
        })

        result = self.vm.qmp('human-monitor-command',
                             command_line='qemu-io cbw "write 0 512K"')
        self.assert_qmp(result, 'return', '')

        # We need second write to trigger throttling
        result = self.vm.qmp('human-monitor-command',
                             command_line='qemu-io cbw "write 512K 512K"')
        self.assert_qmp(result, 'return', '')

        result = self.vm.qmp('human-monitor-command',
                             command_line='qemu-io access "read 0 1M"')
        self.assert_qmp(result, 'return', '')

        self.vm.shutdown()
        log = self.vm.get_log()
        log = re.sub(r'^\[I \d+\.\d+\] OPENED\n', '', log)
        log = re.sub(r'\[I \+\d+\.\d+\] CLOSED\n?$', '', log)
        log = iotests.filter_qemu_io(log)
        return log

    def test_timeout_break_guest(self):
        log = self.do_cbw_timeout('break-guest-write')
        # macOS and FreeBSD tend to represent ETIMEDOUT as
        # "Operation timed out", when Linux prefer
        # "Connection timed out"
        log = log.replace('Operation timed out',
                          'Connection timed out')
        self.assertEqual(log, """\
wrote 524288/524288 bytes at offset 0
512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
write failed: Connection timed out
read 1048576/1048576 bytes at offset 0
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
""")

    def test_timeout_break_snapshot(self):
        log = self.do_cbw_timeout('break-snapshot')
        self.assertEqual(log, """\
wrote 524288/524288 bytes at offset 0
512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 524288/524288 bytes at offset 524288
512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
read failed: Permission denied
""")


if __name__ == '__main__':
    iotests.main(supported_fmts=['qcow2'],
                 supported_protocols=['file'],
                 required_fmts=['copy-before-write'])