The commit and the mirror block job must be able to drop their filter
node at any point.  However, this will not be possible if any of the
BdrvChild links to them is frozen.  Therefore, we need to prevent them
from ever becoming frozen.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NAndrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Message-id: 20190703172813.6868-2-mreitz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>