[RFC] Changes to the lchan and BSC/MSC split

Hey guys, back in January I added ref-counting to the lchan and it has worked to some degree, and we have seen ref-leaks as well (fixed thanks to Andreas). Currently I'm working on integrating OpenBSC into a real MSC at on-waves.com and this has made me read the GSM08.08 specification a bit more. I would like to implement the following. - Remove the refcount from lchan - Replace it with the "transaction" concept. On certain 04.08 messgaes (e.g. paging response, various MM messages) open a transaction from BSC to MSC code. The channel is bound to the transaction. The lchan is getting released when the transaction is finished, in case of the "RSL chan" is going away too early there will be a "clear" signal/method called from the BSC and the MSC side is asked to let it go. The benefit of this: - BSC and MSC are better separated - My MSC code could wrap the transaction into a SCCP connection - Channel leak == transaction_free not getting called. regards holger