Am 06.05.2016 um 14:54 hat Alberto Garcia geschrieben: > On Fri 22 Apr 2016 07:42:37 PM CEST, Kevin Wolf wrote: > > BlockBackends use it to get a back pointer from BdrvChild to > > BlockBackend in any BdrvChildRole callbacks. > > Hmmm... can anyone else use this, other than BlockBackend? If not, why > is it opaque?
If we ever want to call BdrvChild callbacks from somewhere else than the top of the image, there will be others users of this. For example, I could imagine .resize() or .change_media() to propagate through the whole tree when the host_cdrom driver detected a media change. At the moment we probably don't have another use for it, but it's the usual style that callbacks get an opaque value, so I just followed the pattern here. (And I don't want people to abuse this to get back from BDS to BB outside of such callbacks.) Kevin
