So far the number of usable lchans is determined on-the-fly by the
physical channel config. With VAMOS, this becomes more complex, namely
determining whether the BTS is vamos capable.
Instead of calling a function to determine the number of lchans for
every use, rather place the number of valid lchans in int members of the
timeslot struct, and initialize those during timeslot setup.
Actual use of these new fields will follow in a subsequent patch, which
introduces the ts_for_n_lchans() macro to replace current lchan
iteration macros.
Related: SYS#5315 OS#4940
Change-Id: I08027d79db71a23e874b729c4e6173b0f269ee4f
Activating / modifying to a VAMOS mode will require picking specific TSC
Set / TSC. It is a bad idea to pick the TSC in each message encoding
function, rather make this choice centrally.
So far we pick the training sequence code to use based on the timeslot
configuration, and this TSC is determined only upon encoding the RSL
messages.
Instead, pick the TSC to use upon the initial lchan activation /
modification request; store this in the request structs and pass through
the activation / modification code paths.
For VAMOS modes, we also need to pick a TSC Set. Do so also upon activ /
modif request. Note that the TSC Set is not yet applied in this patch,
it will be applied in upcoming VAMOS patches.
The activ / modif request may pass -1 for tsc_set and/or tsc to indicate
no specific choice of TSC Set and TSC, resulting in the same behavior as
before this patch.
For example, lchan->activate.info.tsc* may be passed as -1. The exact
choice for tsc_set and tsc is then stored in lchan->activate.tsc*, i.e.
one level up (the .info sub-struct is considered as immutable input
args). The lchan->activate.tsc* are the values actually encoded in RSL
messages. After the ACK, the lchan->activate.tsc* is stored in
lchan->tsc* to indicate the TSC actually in use. Same for modif.
Note that in 3GPP TS 45.002, the TSC Set are numbered 1 to 4, while the
TSC are numbered 0 to 7. On the wire, though, TSC Set is sent as 0 to 3
value. This is a weird discrepancy, odd choice made by the spec authors.
For conformance with the spec wording, I decided to pass the TSC Set
number as a 1-4 ranged value, and only convert it to the 0-3 on-the-wire
format upon message encoding. So log messages and VTY output will
indicate the first TSC Set as "1", but the first TSC as "0", as defined
in 3GPP TS 45.002, even if that is somewhat weird.
Related: SYS#5315 OS#4940
Change-Id: Ic665125255d7354f5499d10dda1dd866ab243d24
Expose the training sequence code used in the RSL Channel Description IE
as an input parameter.
So far the Channel Description IE is always composed with a training
sequence code from gsm_ts_tsc(). For RSL commands enabling VAMOS mode,
specific training sequence codes are required.
So far, all callers still use gsm_ts_tsc(), making this a patch without
any functional change. Upcoming patches will pass specific TSC as
configured for VAMOS instead, in specific places.
Related: SYS#5315 OS#4940
Change-Id: I49503a6f5d25bb3bc9a0505bd79ed1d5c4f50577
So far we do all channel reassignments by Handover Command. Since
osmo-bsc now supports rassignment of ongoing voice calls, do intra-cell
congestion resolution by Assignment Command.
In effect, add support for expecting an Assignment Command in
handover_test, and expect assignments instead of handovers for
intra-cell congestion resolution test cases.
Related: SYS#5330 OS#3277
Change-Id: Id56a890106b93fcee67ac9401b890e7b63bba421
So far the assignment FSM always tried to satisfy the channel mode and
rate by either re-using the current lchan or finding a new, unused
lchan. For VAMOS however, we want to pick one specific lchan.
Add target_lchan to struct assignment_request and skip all mode matching
and lchan selection when a specific target_lchan is set.
Related: SYS#5315 OS#4940
Change-Id: I71e0d4ff4746706e0be5266e4574d70ca432e3d7
Firstly, do not store the encoded AMR length-value bits in gsm_lchan->*
before an activation/modify has actually succeeded.
And secondly, do not store the AMR LV structure in struct gsm_lchan at
all, but only generate the TLV exactly when a message is being composed.
In gsm48_multirate_config(), generate the LV directly to a msgb instead
of a static buffer first. gsm0408_test.c expected output verifies that
the generated LV bytes remain unchanged.
In lchan_mr_config(), introduce a target mr_conf argument, so that Chan
Act and Mode Modify may generate the filtered AMR config to different
locations (lchan->{activate,modify}.mr_conf_filtered).
Only after receiving an ACK for Activate/Modify, set
lchan->current_mr_conf from lchan->{activate,modify}.mr_conf_filtered.
Use the properly scoped lchan->activate.mr_conf_filtered for Chan Act,
lchan->modify.mr_conf_filtered for Mode Modify and
new_lchan->current_mr_conf for Handover Command as appropriate.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie57f9d0e3912632903d9740291225bfd1634ed47
The GSM48_CMODE_DATA_* rates are completely unused in OsmoBSC anyway,
but there is some code in abis_rsl.c checking its value, and if we were
to start using it that is the place where it should be.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie0e065a5dca5f4a31d5d81e3528a539214a74170
I noticed during testing that an lchan used as TCH/F in fact still had
its channel mode set to Signalling -- because on Assignment, the Speech
mode used to be placed in the *previous* lchan and the new lchan was
never updated after the Activ ACK. This is unbearable confusion which I
complained about numerous times, so far mostly for cosmetic reasons. But
implementing re-assignment properly actually requires this to be cleaned
up.
Keep all volatile chan mode settings in lchan->activate.* or
lchan->modify.*, and only update lchan->* members when an ACK has been
received for those settings. So a failed request keeps a sane state.
Make sure that those settings are in fact updated in the proper lchan,
upon an ACK, so that subsequent re-assignment or mode-modify know the
accurate lchan state.
Related are upcoming patches that sort out the AMR multirate
configuration in a similar fashion, see
Iebac2dc26412d877e5364f90d6f2ed7a7952351e
Ia7519d2fa9e7f0b61b222d27d077bde4660c40b9
Ie57f9d0e3912632903d9740291225bfd1634ed47.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie0da36124d73efc28a8809b63d7c96e2167fc412
So far, only the MSC asked for Assignment via Assignment Request, which
we answer with a BSSMAP Assignment Complete or Assignment Failure when
done.
When Assignment is triggered for any other reason (congestion
resolution, VAMOS, VTY), we will not send any such messages to the MSC.
Additional enum values will be added in subsequent commits:
Id56a890106b93fcee67ac9401b890e7b63bba421 ASSIGN_FOR_CONGESTION_RESOLUTION
If006f5caaf83b07675f57e5665cfa79328da55e6 ASSIGN_FOR_VTY
Related: SYS#5315 OS#4940
Change-Id: Ie0cddbdb00abcec78e153f4ae6d04ce75080a111
The Channel Mode Modify procedure is currently implemented for changing
a TCH lchan from signalling to voice mode. For that, however, it is
re-using (abusing) the channel activation structs and state transitions,
and thus always implies activating a voice stream when the mode
modification is done.
I will add a Channel Mode Modify to enable VAMOS mode soon, so I require
separate structs and state transitions which also work on an lchan that
already has a voice stream established: a struct lchan_modify_info and
LCHAN_EV_REQUEST_MODE_MODIFY, and dedicated assignment FSM state
ASSIGNMENT_ST_WAIT_LCHAN_MODIFIED.
For the part where a Channel Mode Modify enables a voice stream after
switching from signalling to speech mode, still use the channel
activation code path, but only once the mode modification is done.
General improvements:
- To ask for a mode modification, emit an FSM event that ensures a mode
modify only happens when the lchan state allows it.
- The new lchan_modify_info struct reflects only those parts that have
an effect during a mode modification (before the lchan_activate_info
was fully populated, many values not having an effect).
- More accurate logging, indicating "Mode Modify" instead of "Channel
Activation"
A TTCN3 test for the Channel Mode Modify procedure is added in
Idf4efaed986de0bbd2b663313e837352cc139f0f, and the test passes both
before and after this patch is applied.
Related: SYS#4895
Change-Id: I4986844f839b1c9672c61d916eb3d33d0042d747
In subsequent patches, I will add enum lchan_modify_for and enum
assignment_for, I prefer to have similar lchan_activate_for naming.
Change-Id: Ia4420fcd1234dbee92e768e5a32eab13fba29ea9
Soon, there will also be enums with ASSIGNMENT_FOR_* and MODIFY_FOR_*
naming. Add the ACTIVATE_ prefix to the existing enum to clarify.
Change-Id: I12190d4d154a1da6a9ebc9a755ccc2fe382ff188
Use a talloc ctx directly without an intermediate static buffer.
A subsequent patch will add a name tweak for VAMOS secondary lchans, so
it felt appropriate to first clean this.
Change-Id: Idb922605c15242a2cdc7c34668c845a179a15660
Whenever SRVCC EUTRAN->GERAN is performed by the CN, it will set the
Last Used E-UTRAN PLMN Id in order for the BSS to inform the MS
about EUTRAN neighbors once the call is over.
The last part (sending EUTRAN neighs) is already implemented, since same
thing is done as per CSFB. However, we lacked the first part, where the
EUTRAN PLMN Id is recorded for later use.
Actually, in both cases, we end up building the list of neighbors
without taking into accound the PLMN value (hence no filtering of
configured neighs), but it only sends such a list if any PLMN was stored
there, which means this patch is still necessary for a quick fallback to
4G after the call is over.
Related: SYS#5337
Depends: libosmocore.git Change-Id I0e55e947b6fef6dad0cf1a6c16b781bef4cc76c5
Change-Id: Ia5008f11a4c36ef8085a2037d4abddd131086e6e
From 3GPP TS 48.008 sec 3.1.30 "Common ID":
"""
If the SCCP connection is established due to CSFB from E-UTRAN and the MSC supports
return to the last used PLMN after CS fallback, then it should send the COMMON ID message
to the BSS including the Last used E-UTRAN PLMN ID information element if available at
the MSC immediately following the successful SCCP connection setup.
"""
Furthermore, 3GPP TS 48.008 version 16.0.0 Release 16 "3.2.1.21 CLEAR COMMAND",
for field CSFB Indication, states:
"""
NOTE: This information element doesn't serve any useful purpose. MSCs should not send the
information element unless it is required by the recipients (due to the need to interwork
with older versions of the protocol). It is expected that in future versions of the present
document, this information element will be deleted from this message.
"""
Hence, build up the EUTRAN neighbor list based on whether we received
the Last E-UTRAN PLMN ID IE during Common Id. In the future, we should
probably filter the list while populating it based on the received IE.
This change will also allow reusing same mechanism for SRVCC
EUTRAN->GERAN support, where te Last E-UTRAN PLMN ID IE can be found
inside "Old BSS to New BSS information" IE in msg HANDOVER REQUEST.
Related: SYS#5337
Change-Id: I5d290ac55eca5adde1c33396422f4c10b83c03d5
The neighbor configuration storage is fundamentally broken: it requires
all local cells to be configured before being able to list them as
neighbors of each other. Upon config write-back, the neighbor config
however is placed back inline with the other config, and hence a
written-out neighbor config no longer works on program restart.
The cause of this problem is that the config is stored as explicit
pointers between local cells (struct gsm_bts), which of course requires
the pointer to exist before being able to reference it.
Instead, store the actual configuration that the user entered as-is,
without pointers or references to objects that need to be ready. Resolve
the neighbors every time a neighbor is needed.
Hence the user may enter any config at any place in the config file,
even non-working config (like a BTS number that doesn't exist), and the
relation to actual local or remote neighbor cells is made at runtime.
Abort program startup if the initial neighbor configuration contains
errors.
Related: OS#5018
Change-Id: I9ed992f8bfff888b3933733c0576f92d50f2625b
So far the list of penalty timers was stored for an opaque target
pointer. That was either a gsm_bts pointer for a local BTS, or a cell
identifier list pointer for a remote-BSS cell.
Reasons to refactor penalty timers:
- The cell identifier list pointer came from the neighbor configuration
storage, but the way cell neighbor config is stored will change in a
subsequent patch. There will be no more cell identifier lists there.
- Storing object pointers is inherently unsafe -- if an object gets
removed and another gets allocated, the penalty timer could
theoretically remain in force for an unrelated object.
Rather store penalty timers for specific Cell IDs. Since remote-BSS
neighbors can be requested by a cell identifier *list*, use a
gsm0808_cell_id_list2 as key in the list of penalty timers.
Fix handover_test.c: have different CI for each local BTS. So far it was
the same LAC+CI for all BTSes, which now would make the test fail,
because any penalty timer would appear to apply to all local cells.
Related: OS#5018
Change-Id: I72dd6226a6d69c3f653a3174c6f55bf4eecc6885
On lchan activation, we already know the Timing Advance in most
situations: from the Channel Request RACH, or from a previous lchan in
the same cell. Place this information in lchan->activate.info.ta.
So far, the lchan->last_ta (until recently called rqd_ta) was used to
store the initial TA for channel activation -- move the initial TA to
lchan->activate.info.ta, for proper scoping.
Only an inter-cell handover does not yet know a Timing Advance (until
the Handover Detection RACH is received), so indicate
activate.info.ta_known = false for that case.
If ta_known is false, do not include an Access Delay IE in the Channel
Activation message, ensuring that the BTS does not use an arbitrary TA
that is likely inaccurate.
The effect for OsmoBTS is that we will *not* start the downlink SACCH on
channel activation for inter-cell handover, but will wait for a HO RACH
first, and then use the correct TA when enabling downlink SACCH.
Related: OS#4008 SYS#5192
Change-Id: I986bf93e8acd6aef7eaf63ac962480b680aa894f
Originally, the lchan stored only the Timing Advance from the initial
channel request, hence it was called rqd_ta.
Since quite a while now, rqd_ta also stores the most recent Timing
Advance from each received Measurement Report. So rename to last_ta.
This is cosmetic preparation for an upcoming patch that clarifies
whether the Timing Advance is already known for Channel Activation.
Change-Id: I1049526a173819baeb4978db5bf018ba3f1006a0
This new CTRL interface allows users of this BSC (such as attached PCU)
to gather neighbor information.
This interface is needed for PCU to translate ARFCN+BSIC keys provided
by MS in the Um side into CGI + RAC keys used to identify target cells
in RIM procedures against SGSNs on the Gb interface.
This patch extends the already existing neighbor information storage in
the VTY by allowing storage of CGI + RAC (RAC couldn't be stored
beforehand).
Related: SYS#4909
Depends: libosmocore.git Change-Id If48f412c32e8e5a3e604a78d12b74787a4786374
Change-Id: Ib07c9d23026332a207d4b7a0f7b4e76c0094e379
libosmocore > 1.4.0 is required (master, not yet released) since some
fixes done in osmo-bsc code where not cherry-picked to libosmocore APIs.
Depends: libosmocore.git I2bf5635b8536b11d69774d17ac1908019633e3af
Change-Id: I7d5e5ddd174463c2a3d957c8245d2911ce013681
Steve Langasek <steve.langasek@ubuntu.com> submitted some patches
against downstream osmo-bsc 1.3.0 because some possible null derefences
were detected by the compiler on Ubuntu s390x. Code has eveolved since
then and patch doesn't apply directly anymore, since related code
changed (we now use osmo_count in bsc_subscr_get).
The compiled allegedly claimed some null dereference in gsm_lchan_name.
In general code using that function seems to be doing checks for
existing lchan before calling it, or assuming the lchan pointer is not
null, so I couldn't find any major issue.
However, let's add a OSMO_ASSERT to make sure we can easily identify the
issue if an issue ever happens there, since the gsm_lchan_name should
clearly only be called on non null pointers.
Change-Id: If4d12cb1d95ee2a89244bb8f27df839871667387
Before this patch, Get Attributes was sent quicklyafter the OML link
became up, even if the BTS/BB_TRANSC objects were still powered off,
which is wrong since attributes should only be available after the
objects transition out of the Power off state.
Furthermore, information about get attr response already received will
be required in future patches to delay NSVC setting.
Related: OS#4870
Change-Id: I8ec39c7e1f956ffce9aecd58a5590c43200ba086
The only real 1-1 relationship between BTS NM objects is the one between
GPRS Cell and BTS (which is actually a BTS cell).
In our current osmo-bts implementation we don't care much since we only
handle 1-cell BTSses, but let's make the data structure organization
more generic.
Implementation notes:
The gsm_bts_sm is moved to its own file, APIs to allocate are added and
the new public object is hooked correctly in the allocation process of
osmo-bsc.
Change-Id: I06461b7784fa2a78de37383406e35beae85fbad8
In order to activate FACCH/SACCH repetition on the BTS, the classmark 3
IE in the CLASSMARK CHANGE message must be parsed and depending on the
Repeated ACCH Capability bit the RSL_IE_OSMO_REP_ACCH_CAP is added to
the RSL CHAN ACT und RSL CHAN MODE MODIFY. Since
RSL_IE_OSMO_REP_ACCH_CAP is a propritary IE, it may only be added for
BTS type osmo-bts.
Change-Id: I39ae439d05562b35b2e47774dc92f8789fea1a57
Related: OS#4796 SYS#5114
When adding the Lb interface, it is necessary to determine an unused conn id
across *all* SCCP users. Prepare adding Lb by moving conn id creation out of
the gscon code and generalizing.
Change-Id: I12fcb18f6e4380f72929cfe7681bac05330a8c9a
Backwards compatibly, introduce timer groups in OsmoBSC, and move some
non-specified T timers to new X timers:
T993111 -> X3111
T993210 -> X3210
T999 -> X4
Why X4? because there already is an X3 used elsewhere in Osmocom, and I find
it less confusing if X-numbers don't repeat across programs. See
https://osmocom.org/projects/cellular-infrastructure/wiki/List_of_Timer_numbers
Drop unused timers from g_mgw_tdefs. Only X2427 has an actual effect.
(libosmo-mgcp-client recently moved T2427001 to X2427.)
Put libosmo-mgcp-client related timers to the 'mgw' group, like in osmo-msc.
This makes the MGCP timeout configurable for the first time.
Keep previous timer commands as DEFUN_HIDDEN, and also translate the moved T
timers to X timers on-the-fly. All previous VTY commands still work, and new
'timer [(net|mgw)] ...' commands are added. timer.vty shows this.
Remove the "_OPTIONAL" from the legacy "timer" and "show timer" commands, so
that they don't ambiguously overload the new "timer [(net|mgw)] ..." commands.
Related: OS#4539
Related: If097f52701fd81f29bcca1d252f4fb4fca8a04f7 (osmo-mgw)
Change-Id: I4beec47502afa193dee343869c4be55dc6a4b536
During handover cleanup due to a Clear Command from the MSC, do not send
another Clear Request to the MSC. Only send that when no Clear Command was
received yet.
Add a flag rx_clear_command per gscon instance, indicating whether a Clear
Command was received, and exit early in gscon_bssmap_clear() when true.
This is part of patches fixing the rate counters around handover, which uncover
some bugs:
- Another patch enables proper handover result handling when receiving a Clear
Command.
- After that, the handover_end() handling would always cause sending a Clear
Request, even if a Clear Command was already received.
- This patch removes the extraneous Clear Request, for this scenario and for
all other corner cases that might still exist.
Related: OS#4736
Change-Id: Iab82cac0a7ffa7d36338c8ff7c0618a813025f13
So far, during inter-BSC outgoing handover, when receiving an RR Handover
Failure from the MS, it would be counted as 'error'. Instead, add the 'failed'
counter like for all other HO types.
It may make sense to omit the 'failed' counter for inter-BSC *incoming*
handover, because then we won't receive an RR Handover Failure message. I
probably got those two mixed up during initial development.
Related: OS#4736
Change-Id: I9a61d5cc7273a830ba4e66e43e4aac6cdb707471
In some (error-) cases we might be unable to determine which BTS to use
when counting handover events. We don't want to loose these events
because then ctr(bsc) == sum(ctr(bsc->bts)) would not be true anymore.
Those events are now counted by a counter in struct gsm_network which
uses an index that is out of range for regular BTS (65536).
Change-Id: Ic0f3edd5dc014c4eac5e8423133633a3e5d4c13e
Related: SYS#4877
Currently the counters don't distinguish between intra-cell and
intra-bsc handover.
Add _CTR_INTRA_CELL_HO_ and _CTR_INTRA_BSC_HO_ counters to track
intra-cell/bsc handover separately.
Change-Id: I3a1195640b99813036c9f1426ee5f07548e26547
Related: SYS#4877
With upcoming next commit, the file will contain far more code that
simply ramping, so rename it to be more generic.
Change-Id: I8c368ab87e264439dea4ccf556821a44664cdbb0
In the big mess of gsm_data we reached a point where we have multiple
functions doing the same thing, most probably because it's hard finding
stuff in there. Let's drop one of them (the one which less callers) and
move it to bts.*, where it belongs.
Change-Id: I9071a0ab250844619280fbe2be63ed99f2c87eb1
Place all code related to the object into the related file.
Having all the data model in one file made sense in early stage of
development to make progress quickly, but nowadays it hurts more than
helps, due to constantly growing size and more and more bits being
added to the model, gaining in complexity.
Currently, having lots of different objects mixed up in gsm_data.h is a hole
of despair, where nobody can make any sense were to properly put new stuff
in, ending up with functions related to same object in different files
or with wrong prefixes, declarations of non-existing functions, etc.
because people cannot make up their mind on strict relation to objects
in the data model.
Splitting them in files really helps finding code operating on a
specific object and helping with logically splitting in the future.
Change-Id: I00c15f5285b5c1a0109279b7ab192d5467a04ece
In various places that receive an error cause from RSL and place it in
lchan.release.rsl_error_cause, translate it to an RR cause and place that in
the recently added lchan.release.rr_cause. Hence the RR Channel Release message
now reflects more specific error causes when the reason for the error was
received in an RSL message's cause value.
Change-Id: I46eb12c91a8c08162b43dd22c7ba825ef3bbc6ac
Neels Hofmeyr
Pau Espin
Vadim Yanitskiy
Philipp Maier
Daniel Willmann