blockdev: unify qmp_drive_backup and drive-backup transaction paths

Issuing a drive-backup from qmp_drive_backup takes a slightly
different path than when it's issued from a transaction. In the code,
this is manifested as some redundancy between do_drive_backup() and
drive_backup_prepare().

This change unifies both paths, merging do_drive_backup() and
drive_backup_prepare(), and changing qmp_drive_backup() to create a
transaction instead of calling do_backup_common() direcly.

As a side-effect, now qmp_drive_backup() is executed inside a drained
section, as it happens when creating a drive-backup transaction. This
change is visible from the user's perspective, as the job gets paused
and immediately resumed before starting the actual work.

Also fix tests 141, 185 and 219 to cope with the extra
JOB_STATUS_CHANGE lines.

Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/tests/qemu-iotests/219 b/tests/qemu-iotests/219
index e0c51662c0..655f54d881 100755
--- a/tests/qemu-iotests/219
+++ b/tests/qemu-iotests/219
@@ -63,7 +63,7 @@ def test_pause_resume(vm):
                 # logged immediately
                 iotests.log(vm.qmp('query-jobs'))
 
-def test_job_lifecycle(vm, job, job_args, has_ready=False):
+def test_job_lifecycle(vm, job, job_args, has_ready=False, is_mirror=False):
     global img_size
 
     iotests.log('')
@@ -135,6 +135,9 @@ def test_job_lifecycle(vm, job, job_args, has_ready=False):
     iotests.log('Waiting for PENDING state...')
     iotests.log(iotests.filter_qmp_event(vm.event_wait('JOB_STATUS_CHANGE')))
     iotests.log(iotests.filter_qmp_event(vm.event_wait('JOB_STATUS_CHANGE')))
+    if is_mirror:
+        iotests.log(iotests.filter_qmp_event(vm.event_wait('JOB_STATUS_CHANGE')))
+        iotests.log(iotests.filter_qmp_event(vm.event_wait('JOB_STATUS_CHANGE')))
 
     if not job_args.get('auto-finalize', True):
         # PENDING state:
@@ -218,7 +221,7 @@ with iotests.FilePath('disk.img') as disk_path, \
 
     for auto_finalize in [True, False]:
         for auto_dismiss in [True, False]:
-            test_job_lifecycle(vm, 'drive-backup', job_args={
+            test_job_lifecycle(vm, 'drive-backup', is_mirror=True, job_args={
                 'device': 'drive0-node',
                 'target': copy_path,
                 'sync': 'full',