The BSC is the wrong network component to originate USSD messaging, as can be
seen in the hacks in the USSD code: for example, the BSC would send a CM
Service Accept message as if an MSC had accepted the connection, dispatch a
USSD and directly send some RR release message (without proper tear down
messaging like the lchan_fsm does these days). This made sense in the osmo-nitb
world, but by now we are aiming for solid 3GPP compliance. The BSC shall not
originate USSD messages.
Deprecate all VTY and CTRL commands related to USSD:
VTY
[no] bsc-welcome-text
[no] bsc-msc-lost-text
[no] bsc-grace-text
[no] missing-msc-text
(the commands with 'no' are ignored, without 'no' lead to an error)
CTRL
ussd-notify-v1
Drop (already unused) ussd.h.
Drop gsm_04_80.h, gsm_04_80_utils.c, and all calling code.
Drop "RF grace" notification, where osmo-bsc was able to notify active
subscribers that the RF was being turned off.
Change-Id: Iaef6f2e01b4dbf2bff0a0bb50d6851f50ae79f6a
Add FSMs:
- timeslot_fsm: handle dynamic timeslots and OML+RSL availability.
- lchan_fsm: handle an individual lchan activation, RTP stream and release,
signal the appropriate calling FSMs on success, failure, release.
- mgw_endpoint_fsm: handle one entire endpoint with several CI.
- assignment_fsm: BSSMAP Assignment Request.
- handover_fsm: all of intra, inter-MO and inter-MT handover.
Above FSMs absorb large parts of the gscon FSM. The gscon FSM was surpassing
the maximum amount events (32), and it is more logical to treat assignment,
handover and MGW procedures in separate FSMs.
- Add logging macros for each FSM type:
- LOG_TS()
- LOG_LCHAN()
- LOG_MGWEP(), LOG_CI()
- LOG_ASSIGNMENT()
- LOG_HO()
These log with the osmo_fsm_inst where present.
New style decision: logging without a final newline char is awkward,
especially for gsmtap logging and when other logs interleave LOGPC() calls;
we have various cases where the final \n goes missing, and also this invokes
the log category checking N times instead of once.
So I decided to make these macros *always* append a newline, but only if
there is no final newline yet. I hope that the compiler optimizes the
strlen() of the constant format strings away. Thus I can log with or without
typing "\n" and always get an \n termination anyway.
General:
- replace osmo_timers, state enums and program-wide osmo_signal_dispatch()
with dedicated FSM timeouts, states and events.
- introduce a common way to handle Tnnn timers: gsm_timers.h/.c: struct T_def.
These can be used (with some macro magic) to define a state's timeout once,
and not make mistakes for each osmo_fsm_inst_state_chg().
Details:
bsc_subscr_conn_fsm.c:
- move most states of this FSM to lchan_fsm, assignment_fsm, handover_fsm and
mgw_endpoint_fsm.
- There is exactly one state for an ongoing Assignment, with all details
handled in conn->assignment.fi. The state relies on the assignment_fsm's
timeout.
- There is one state for an ongoing Handover; except for an incoming Handover
from a remote BSS, the gscon remains in ST_INIT until the new lchan and conn
are both established.
- move bssmap_add_lcls_status() to osmo_bsc_lcls.c
abis_rsl.c:
- move all dynamic timeslot logic away into timeslot_fsm. Only keep plain send/receive functions in
abis_rsl.c
- reduce some rsl functions to merely send a message, rename to "_tx_".
- rsl_ipacc_mdcx(): add '_tx_' in the name; move parts that change the lchan state out into the
lchan_fsm, the lchan->abis_ip.* are now set there prior to invoking this function.
- move all timers and error/release handling away into various FSMs.
- tweak ipa_smod_s_for_lchan() and ipa_rtp_pt_for_lchan() to not require an
lchan passed, but just mode,type that they require. Rename to
ipacc_speech_mode*() and ipacc_payload_type().
- add rsl_forward_layer3_info, used for inter-BSC HO MO, to just send the RR
message received during BSSMAP Handover Command.
- move various logging to LOG_LCHAN() in order to log with the lchan FSM instance.
One drawback is that the lchan FSM is limited to one logging category, i.e. this moves some logging
from DRR to DRSL. It might actually make sense to combine those categories.
- lose LOGP...LOGPC logging cascades: they are bad for gsmtap logging and for performance.
- handle_classmark_chg(): change logging, move cm2 len check out of the cm3 condition (I hope that's
correct).
- gsm48_send_ho_cmd(): split off gsm48_make_ho_cmd() which doesn't send right away, so that during
inter-bsc HO we can make an RR Handover Command to send via the MSC to the remote BSS.
assignment_fsm.c:
- the Chan Mode Modify in case of re-using the same lchan is not implemented
yet, because this was also missing in the previous implementation (OS#3357).
osmo_bsc_api.c:
- simplify bsc_mr_config() and move to lchan_fsm.c, the only caller; rename to
lchan_mr_config(). (bsc_mr_config() used to copy the values to mr_bts_lv
twice, once by member assignment and then again with a memcpy.)
- During handover, we used to copy the MR config from the old lchan. Since we
may handover between FR and HR, rather set the MR Config anew every time, so
that FR rates are always available on FR lchans, and never on HR lchans.
Depends: I03ee7ce840ecfa0b6a33358e7385528aabd4873f (libosmocore),
I1f2918418c38918c5ac70acaa51a47adfca12b5e (libosmocore)
Change-Id: I82e3f918295daa83274a4cf803f046979f284366
We can now either page an invidual BTS directly or page several BTS in a
given location area. This decision is taken based on the contents of the
cell identifier list in the paging request. Select a set of BTS for paging
while processing the cell identifier list, rather than requiring the
paging layer to loop over all BTS in the MSC.
This change requires some adjustment in bssap_test. In particular,
this test must now add a BTS to its network in order to pass.
The purpose of this change is to make the layering a bit cleaner.
There is one functional change: We no longer abort paging if paging fails
for a particular BTS. Instead, we keep trying to page on other BTS.
Change-Id: Ic1c72c7f83e53988eb9fedf314b1dc459836833d
Suggested-by: Harald Welte
Depends: Ic7772e75c3d7fb0df6e17e118bb33b3248352d4d
Related: OS#2753
This builds upon https://gerrit.osmocom.org/#/c/5698/ which implements
support for paging by LAI.
The ttcn3 test TC_paging_imsi_nochan_ci passes with this code when
run in isolation. It does not pass if another paging test (such as
TC_paging_imsi_nochan_lai) is executed beforehand. This problem
looks similar to the scenario tested in TC_paging_imsi_a_reset.
Change-Id: Ic7772e75c3d7fb0df6e17e118bb33b3248352d4d
Depends: Ic3c62ff0fccea586794ea4b3c275a0685cc9326e
Related: OS#2753
The call-back was needed inside the NITB to determine which part (CC,
SMS, ...) had triggered a given paging. A pure BSC doesn't need that
feature, so let's get rid of it.
The 'void *cbfn_data' is replaced with a 'struct bsc_msc_data *', as
all callers use it with that type.
Change-Id: I8839e8338d3ad1a91b41e687e8412fcdca3fd9ab
This is the first step in creating this repository from the legacy openbsc.git.
Like all other Osmocom repositories, keep the autoconf and automake files in
the repository root. openbsc.git has been the sole exception, which ends now.
Change-Id: I9c6f2a448d9cb1cc088cf1cf6918b69d7e69b4e7
Neels Hofmeyr
Harald Welte