Hi Mike, I've just been reading through this stuff, you've put a lot effort into it. I'm still really worried by how invasive it is to the core dm code. The current code is structured to support different interfaces (eg. ioctl, dmfs). I see sysfs as simply another user interface, albeit a read only one, so it would be nice if it could be written without embedding kobjects etc. in the core dm structs. The reason you're finding this hard to do is that I never intended for people to run more than one interface at the same time, so there is no update mechanism to inform the interfaces of any changes initiated by a different interface. Adding such a feature is not something I wanted to do, since it will end up defining what it is possible to do using a user interface, for example the ioctl interface supports 2 namespaces for devices (name, uuid), whereas dmsfs supports an arbitrary number. How should we map these onto each other ? Can you come up with a list of events that your sysfs interface is iterested in ? eg. you are probably interested in a device rename, a table load etc. Once we have this list we can maybe let the interfaces register callbacks for notification of these changes. Hope this makes sense. - Joe