iotests: Add mirror-ready-cancel-error test

Test what happens when there is an I/O error after a mirror job in the
READY phase has been cancelled.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Tested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20211006151940.214590-14-hreitz@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

tests/qemu-iotests/tests/mirror-ready-cancel-error

@@ -0,0 +1,143 @@
+#!/usr/bin/env python3
+# group: rw quick
+#
+# Test what happens when errors occur to a mirror job after it has
+# been cancelled in the READY phase
+#
+# Copyright (C) 2021 Red Hat, 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, see <http://www.gnu.org/licenses/>.
+#
+
+import os
+import iotests
+
+
+image_size = 1 * 1024 * 1024
+source = os.path.join(iotests.test_dir, 'source.img')
+target = os.path.join(iotests.test_dir, 'target.img')
+
+
+class TestMirrorReadyCancelError(iotests.QMPTestCase):
+    def setUp(self) -> None:
+        assert iotests.qemu_img_create('-f', iotests.imgfmt, source,
+                                       str(image_size)) == 0
+        assert iotests.qemu_img_create('-f', iotests.imgfmt, target,
+                                       str(image_size)) == 0
+
+        self.vm = iotests.VM()
+        self.vm.launch()
+
+    def tearDown(self) -> None:
+        self.vm.shutdown()
+        os.remove(source)
+        os.remove(target)
+
+    def add_blockdevs(self, once: bool) -> None:
+        res = self.vm.qmp('blockdev-add',
+                          **{'node-name': 'source',
+                             'driver': iotests.imgfmt,
+                             'file': {
+                                 'driver': 'file',
+                                 'filename': source
+                             }})
+        self.assert_qmp(res, 'return', {})
+
+        # blkdebug notes:
+        # Enter state 2 on the first flush, which happens before the
+        # job enters the READY state.  The second flush will happen
+        # when the job is about to complete, and we want that one to
+        # fail.
+        res = self.vm.qmp('blockdev-add',
+                          **{'node-name': 'target',
+                             'driver': iotests.imgfmt,
+                             'file': {
+                                 'driver': 'blkdebug',
+                                 'image': {
+                                     'driver': 'file',
+                                     'filename': target
+                                 },
+                                 'set-state': [{
+                                     'event': 'flush_to_disk',
+                                     'state': 1,
+                                     'new_state': 2
+                                 }],
+                                 'inject-error': [{
+                                     'event': 'flush_to_disk',
+                                     'once': once,
+                                     'immediately': True,
+                                     'state': 2
+                                 }]}})
+        self.assert_qmp(res, 'return', {})
+
+    def start_mirror(self) -> None:
+        res = self.vm.qmp('blockdev-mirror',
+                          job_id='mirror',
+                          device='source',
+                          target='target',
+                          filter_node_name='mirror-top',
+                          sync='full',
+                          on_target_error='stop')
+        self.assert_qmp(res, 'return', {})
+
+    def cancel_mirror_with_error(self) -> None:
+        self.vm.event_wait('BLOCK_JOB_READY')
+
+        # Write something so will not leave the job immediately, but
+        # flush first (which will fail, thanks to blkdebug)
+        res = self.vm.qmp('human-monitor-command',
+                          command_line='qemu-io mirror-top "write 0 64k"')
+        self.assert_qmp(res, 'return', '')
+
+        # Drain status change events
+        while self.vm.event_wait('JOB_STATUS_CHANGE', timeout=0.0) is not None:
+            pass
+
+        res = self.vm.qmp('block-job-cancel', device='mirror')
+        self.assert_qmp(res, 'return', {})
+
+        self.vm.event_wait('BLOCK_JOB_ERROR')
+
+    def test_transient_error(self) -> None:
+        self.add_blockdevs(True)
+        self.start_mirror()
+        self.cancel_mirror_with_error()
+
+        while True:
+            e = self.vm.event_wait('JOB_STATUS_CHANGE')
+            if e['data']['status'] == 'standby':
+                # Transient error, try again
+                self.vm.qmp('block-job-resume', device='mirror')
+            elif e['data']['status'] == 'null':
+                break
+
+    def test_persistent_error(self) -> None:
+        self.add_blockdevs(False)
+        self.start_mirror()
+        self.cancel_mirror_with_error()
+
+        while True:
+            e = self.vm.event_wait('JOB_STATUS_CHANGE')
+            if e['data']['status'] == 'standby':
+                # Persistent error, no point in continuing
+                self.vm.qmp('block-job-cancel', device='mirror', force=True)
+            elif e['data']['status'] == 'null':
+                break
+
+
+if __name__ == '__main__':
+    # LUKS would require special key-secret handling in add_blockdevs()
+    iotests.main(supported_fmts=['generic'],
+                 unsupported_fmts=['luks'],
+                 supported_protocols=['file'])

tests/qemu-iotests/tests/mirror-ready-cancel-error.out

@@ -0,0 +1,5 @@
+..
+----------------------------------------------------------------------
+Ran 2 tests
+
+OK