The reason for this is quite simple: We want to make sure anyone
running a customized version of OpenBSC to operate a network will
have to release all custom modifiations to the source code.
We now have a function that generates BSSGP PS and CS paging request.
It is called from the libgtp code when we receive a GTP packet from
the GGSN for a MM context that is in SUSPEND state. We then issue
a PS paging request to the Cell with the BVCI where the last RA update
was being performed.
TODO: We still don't enqueue the GTP packet (and transmit it on paging
complete), and we don't rate-limit the paging requests, i.e. every GTP packet
will trigger another paging request.
We probably also need some kind of logic that marks the phone as UNREGISTERED
if it doesn't respond to paging requests for some time.
* separate the LLME and LLE state in the LLC layer
* introduce gprs_llgmm_assign() function for LLGMM-ASSIGN.req primitive
* change QoS profile to match 'real' SGSN
* Update the new TLLI when assigning a P-TMSI
The result now is that the LLC layer is notified of TLLI changes, which in turn
means it doesn't allocate a new LLE structure every TLLI change, which again
in turn means that the UI frame sequence number does not reset to zero.
As a result, MS should no longer ignore frames based on wrong UI sequence number.
When we send a downlink unit-data request via BSSGP, there is a lot
of information that needs to be copied from the mm context, such as
the IMSI, DRX parametes, MS radio access parameters, ...
This is a quite strange layering violation, since we now need to pass
a pointer to the MM ctx from GMM through LLC into BSSGP :(
This is of course not the correct way of dealing with it, but for
now it should make the Ericsson Mobile Plafrom based phones happy
(they insist to do a suspend/resume cycle before pdp ctx act)
We now actually are much more in line with what the specification
says. We track the blocked/unblocked state, we don't accept
signalling messages on PTP functional entities (and vice versa),
and we don't simply create a BVC context with messages other than
BVC-RESET.
In order to reuse the existing bssgp_tx_* functions without pulling
in the dependencies of gprs_bssgp.c, we have to move those functions
to gprs_bssgp_util.c
Furthermore, we can remove gbprox_nsi and replace it with bssgp_nsi,
and we can do proper processing of BVC-RESET messages coming from
the SGSN on the signalling BVC. In that case we need to send RESET
messages to all the BSS.