(I just wanted to reply quickly to this point, I'll read the rest of the e-mail later)
On Fri 16 Nov 2018 05:34:08 PM CET, Max Reitz <mre...@redhat.com> wrote: > > GRAPH_MOD with the meaning that Berto suggested isn't weird or > > complicated to understand. It's only the wrong tool because it > > blocks more than we want to block. But if we didn't care about that, > > it could be just another permission like any other. That's the way that I understood it. Or, more precisely, I'm basing my current code on those assumptions because it's a simple starting point to have something working with the current permission system. But I'm of course open to trying a different approach. > The meaning Berto has suggested (AFAIU) is never taking the permission > at all but just querying whether it is shared by all current parents > before doing a graph change. That would be a quick way to test it, and I agree that it's unorthodox, but it's useful to explain how I understood the meaning of GRAPH_MOD. But you could for example make BDRVReopenState a parent of the BDS (and replace BDRVReopenState.bs with a BdrvChild). Berto
