Re: [libvirt PATCH v2 25/31] qemu_snapshot: implement deletion of external snapshot

When deleting snapshot we are starting block-commit job over all disks that are part of the snapshot. This operation may fail as it writes data changes to the backing qcow2 image so we need to wait for all the disks to finish the operation and wait for correct signal from QEMU. If deleting active snapshot we will get `ready` signal and for inactive snapshots we need to disable autofinalize in order to get `pending` signal. At this point if commit for any disk fails for some reason and we abort the VM is still in consistent state and user can fix the reason why the deletion failed. After that we do `pivot` or `finalize` if it's active snapshot or not to finish the block job. It still may fail but there is nothing else we can do about it. Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com&gt; --- src/qemu/qemu_snapshot.c | 256 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 236 insertions(+), 20 deletions(-)