The client needs a new more estensible text-based upcall to gssd, to make it easier to support some features that are needed for new krb5 enctypes, for callbacks, etc. We will have to continue to support the old upcall for backwards compatibility with older gssd's. To simplify upgrades, as well as testing and debugging, it would help if we can upgrade gssd without having to choose at boot (or module-load) time whether we want the new or the old upcall. That means that when gssd opens an rpc upcall pipe, we'd like to just start using whichever version it chose immediately--ideally without having to wait the 30 seconds that it would normally take for upcalls already queued on the wrong upcall pipe to time out. The following patches do that by queueing the upcalls on whichever of the two upcall pipes (the new one and the old one) that somebody holds open. If nobody's opened anything yet, then upcalls are provisionally queued on the new pipe. I add a pipe_open method to allow the gss code to keep track of which pipe is open, to prevent anyone from attempting to open both pipes at once, and to cancel any upcalls that got queued to the wrong pipe. I did some minimal testing with the old upcall, but haven't tested the new upcall yet. (Olga, could you do that?) So this is just an RFC at this point. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
