Commit Graph

921 Commits

Author SHA1 Message Date
Jacob Erlbeck 580edbc326 sched: Assert that the generated message is not empty
Currently the msg data is accessed and index 0 assuming the msg is
not empty. While this should be always the case, the msg can be
empty if there are software errors in the message creation functions.

This commit adds an assertion to catch this kind of bugs.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:13 +01:00
Jacob Erlbeck 8e323b39f9 edge: Set the EGPRS window parameters
Currently the GPRS parameters are used, which is ok for the WS but
not for the SNS.

This commit uses RLC_EGPRS_SNS and RLC_EGPRS_MIN_WS for the window
configuration.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:13 +01:00
Jacob Erlbeck 869449cdd0 edge: Move EGPRS setup from setup_tbf to tbf_alloc_ul_tbf
Currently the EGPRS mode is enabled in setup_tbf depending on the
values of egprs_ms_class and bts->egprs_enabled (both must be != 0).
This makes it difficult to set different values (like window
parameters) depending on the direction.

This commit moved the initialisation part to tbf_alloc_ul_tbf und
just leaves the setting of the ms_class to setup_tbf.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:13 +01:00
Jacob Erlbeck 8f8197f3fd rlc: Make WS and SNS variable
Currently the values for WS and SNS are fixed to 64 (WS) and 128
(SNS) which are the only values that can be used with GPRS. On the
other hand, EGPRS requires an SNS of 2014 and a WS in the range of
64 to 1024.

This commit adds member variables and setters to both window
classes. By default, the GPRS values are being used.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck a3a567e765 rlc: Add constructor to window classes
Currently the gprs_rlc_dl_window and gprs_rlc_ul_window do not have
constructors, but need to get initialized explicitly.

This commit adds constructors to both classes and removes explicit
external initialization code.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck e1ca87f057 rlc/edge: Consistently use uint16_t for BSNs and SSNs
Currently in some places uint8_t is being used to encode BSNs and
SSNs. This is inconsistent and (even worse) not enough for EPGRS
which uses an SNS of 2014.

This commit changes these to uint16_t.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck 93c55d04e5 rlc: Add and use mod_sns(bsn) method
Currently there is only a mod_sns() method which is being used in
expression like bsn_expr & win.mod_sns(). This only works, because
it is known that mod_sns() is (sns() - 1) where sns() in turn is
always 2^n. This is error prone, hard to read, and relies on window
specifics that should be kept inside the respective module.

This commit adds a mod_sns(uint bsn) method to gprs_rlc_ul_window and
gprs_rlc_dl_window, that encapsulates and hides this optimized
computation.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck 2b3121eebf edge: Support EGPRS uplink Ack/Nack messages
This commit adds EGPRS UL Ack/Nack encoding based on the CSN1 code.

Note that the bitmap encoding is still broken and not easy to fix
with the CSN1 framework, especially w.r.t. the length field.
Therefore this implementation will be abandoned and replaced by a
bitvec based one.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck 2e3a81e4b3 rlc: Use a pointer instead of repeated selector chains
Currently the same selector chain is used several times in the same
function.

This commit adds a pointer to Packet_Uplink_Ack_Nack and uses that
instead.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck 5c75480e90 edge: Move the GPRS UL Ack/Nack encoding into a separate function
Currently the Encoding::write_packet_uplink_ack function only
supports GPRS.

Split this function into a generic and a GPRS specific part.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck d88bb2e825 rlc: Dump RLC data for debugging
Log incoming RLC data messages and RLC data units to LOGL_DEBUG.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck c362df25a2 pcu: Fix memory corruption bugs (ASAN)
ASAN has found improper deletion of objects. These only occur
on shutdown but makes it impossible to run the test cases with
full ASAN support.

This commit fixes some of them and deactivates the freeing of the_pcu.bctx
which may cause a corruption in BTS::~BTS() later on.

Note that the latter is only a work-aound and should be fixed
properly. It will leak bctx objects, but this is currently not
critical, since gprs_bssgp_destroy is only called once, immediately
before a call to exit().

Ticket: OW#1572
Sponsored-by: On-Waves ehf
2016-02-01 13:56:32 +01:00
Jacob Erlbeck 27dc941475 edge: Remove leftover comments from encoding.c
Sponsored-by: On-Waves ehf
2016-01-08 11:14:15 +01:00
Jacob Erlbeck ead5e4724c edge: Fix data block decoder (Coverity)
Use a signed integer instead of an unsigned one for num_chunks
which can set to a negative value on error.

Ensure that chunks is not dereferenced if it is NULL. In fact
that will not happen currently, since num_chunks is now always
<= 0 if chunks == NULL.

Fixes: Coverity CID 1347433, 1347434, 1347435

Sponsored-by: On-Waves ehf
2016-01-08 10:14:50 +01:00
Jacob Erlbeck 6e75bc7fe3 sched: Change next_ctrl_prio increment
Currently the control block scheduler does not seem to be fair in all
cases. At least it happend while testing the EGPRS code, that a
Uplink Ack/Nack message got never be sent, because a Downlink
assignment took over all the times.

This commit changes the round robin code to always increment the
priority offset by 1 instead of (i + 1). The former definitely
ensures that every message type gets the highest priority after some
steps. The latter might be more fair in some situations, but that and
its correctness are not proven.

Sponsored-by: On-Waves ehf
2015-12-16 19:57:13 +01:00
Jacob Erlbeck 845c01ef3f edge: Remove unused GPRS functions
This commit removes the code that is no longer used due to the commit
"Use a single PDCH rcv_data_block method for GPRS and EGPRS".

Sponsored-by: On-Waves ehf
2015-12-16 19:57:13 +01:00
Jacob Erlbeck 554a835e90 edge: Use a single PDCH rcv_data_block method for GPRS and EGPRS
Currently GPRS is handled by the old code path while EGPRS already
uses the unified functions. The rcv_block_egprs is basically not
specific to EGPRS and just needs minor modifications to handle GPRS.

This commit turns gprs_rlcmac_pdch::rcv_block_egprs into a unified
rcv_data_block method and uses it for GPRS, too.

Note that the logging messages of the new parser are different.

Sponsored-by: On-Waves ehf
2015-12-16 19:57:09 +01:00
Jacob Erlbeck 39c6c7f738 edge: Implement gprs_rlcmac_pdch::rcv_block_egprs
This commit replaces the stub by a method that decodes the block
first, and passes it to the TBF object associated with the TFI.

Sponsored-by: On-Waves ehf
2015-12-16 19:55:52 +01:00
Jacob Erlbeck b3100e187b edge: Add methods for unified GPRS/EGPRS UL data block handling
The current rcv_data_block_acknowledged_gprs method is tightly
coupled to GPRS.

This commit adds variants of the involved methods that support
EGPRS and GPRS RLC encodings likewise.

Sponsored-by: On-Waves ehf
2015-12-16 19:55:18 +01:00
Jacob Erlbeck e8f5fe5255 tbf: Refactor parts of extract_tlli into set_tlli_from_ul
Currently gprs_rlcmac_tbf::extract_tlli takes care of decoding and
the TBF update. These are really different things and doing the
decoding in extract_tlli makes EGPRS support more complex.

This commit moves the TBF state related part into a new method
gprs_rlcmac_tbf::set_tlli_from_ul.

Sponsored-by: On-Waves ehf
2015-12-16 19:37:49 +01:00
Jacob Erlbeck ce1beb423c edge: Store GprsCodingScheme in gprs_rlc_data
Currently the coding scene is stored as number N, where there scheme
is CS-N.

This commit replaces this by a GprsCodingScheme type cs value. The
gprs_rlcmac_cs table is no longer needed and thus removed.

Sponsored-by: On-Waves ehf
2015-12-16 19:37:08 +01:00
Jacob Erlbeck 784a0bd000 edge: Add is_received and invalidate_bsn to gprs_rlc_ul_window
These methods will be needed for EGPRS decoding.

The is_received method returns true iff a block with the given BSN
has already been received in the current window. A call to
invalidate_bsn marks the block as not received.

Sponsored-by: On-Waves ehf
2015-12-16 19:37:08 +01:00
Jacob Erlbeck d87e1d6ab7 rlc: Do not raise_v_q in receive_bsn
Currently gprs_rlc_ul_window::receive_bsn calls raise_v_q and returns
the number of RLC data blocks that can be taken from the queue. This
does not fit the EGPRS feature to put 2 independant data blocks in a
single RLC block.

This commit removes raise_v_q from receive_bsn, hence it must be
called explicitely to get the number of processable data blocks.

Sponsored-by: On-Waves ehf
2015-12-16 19:37:08 +01:00
Jacob Erlbeck 6167925147 edge: Add test cases for rlc_data_from_ul_data
This checks the example test cases given in appendix B of
TS 44.060.

Sponsored-by: On-Waves ehf
2015-12-16 19:36:10 +01:00
Jacob Erlbeck 4abc686d76 edge: Add unified decoder methods for GPRS/EGPRS
This commit adds new RLC block decoder functions that support both
GPRS and EGPRS. The code path is selected based on the value of the
GprsCodingScheme cs object.

- rlc_parse_ul_data_header
        parses the header of an RLC data block including the E and FBI/TI
        flags (currently supported CS-1 - CS-4, MCS-1 - MCS-4).

- rlc_copy_to_aligned_buffer
        copies an RLC data unit to a byte aligned buffer and returns
        the unit's length.

- rlc_get_data_aligned
        is a convenience wrapper around rlc_copy_to_aligned_buffer
        that avoids copying if the data unit is already byte aligned.

Sponsored-by: On-Waves ehf
2015-12-16 19:36:09 +01:00
Jacob Erlbeck 392a545336 edge: Add information about data blocks to GprsCodingScheme
This commit adds the methods maxDataBlockBytes and numDataBlocks
which provide information about the data areas within RLC messages.
In these areas, the extension bytes, TLLI, and the LLC data are
stored.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:43 +01:00
Jacob Erlbeck 4aa78a8bea rlc: Check endianness for bit field declarations
Currently the declarations of rlc_ul_header, rlc_dl_header, and
rlc_li_field silently assume that a gcc for a little endian platform
is being used.

This commit adds '#if OSMO_IS_LITTLE_ENDIAN' the ensure the correct
byte ordering.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:43 +01:00
Jacob Erlbeck 6c3dc61db5 edge: Add header type property to GprsCodingScheme
The header type depends on the coding scheme, for GPRS there is a
single data header type per direction, for EGPRS there are 3 per
direction. In addition, control block header types are used with CS-1
only, so there is one of the per direction altogether for GRPS and
EGPRS.

This commit adds the header type enum and two methods headerTypeData
and headerTypeControl.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:43 +01:00
Jacob Erlbeck 3b802e3c4a edge: Rename rcv_data_block_acknowledged
This commit renames rcv_data_block_acknowledged to
rcv_data_block_acknowledged_gprs to separate it from EGPRS data block
decoding.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:43 +01:00
Jacob Erlbeck 690a734ebf edge: Add gprs_rlcmac_pdch::rcv_block_egprs stub
This stub function gets called when an EGPRS data package arrives.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 9e862e1e7f edge: Use GprsCodingScheme to adjust the UL RLC block size
Currently the block size is mapped by a switch statement to strip
extra bits that are not used for RLC blocks. That information is
already available via the GprsCodingScheme class.

This commit moves the CS/MCS detection to the rcv_block message and
passes the cs object via rcv_block_gprs, where the length gets
adjusted, to gprs_rlcmac_pdch::rcv_data_block_acknowledged. There the
switch statement is removed.

Note that the TbfTest.err changes due to an additional log message.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck d0222cfe2d edge: Add test for GprsCodingScheme
This test checks constructors, predicates, and operators of the
GprsCodingScheme class.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 409f980a18 edge: Add GprsCodingScheme class
Currently the coding scheme is checked and compared at different
places which makes in cumbersome to extend it for EGPRS.

This class encapsules the coding scheme and provides required meta
information like sizes as well as helper methods.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 14e00f8f66 edge: Extend gprs_rlcmac_dl_tbf::handle by egprs_ms_class
The multislot (MS) class and the EGPRS MS class can also be passed
via BSSGP in an MS Radio Access Capability element which can
optionally be contained in a DL-UNITDATA PDU. While this case is fully
supported for GPRS, the EGPRS MS class in BSSGP messages is ignored.

This commit extends gprs_rlcmac_dl_tbf::handle to pass the EGPRS MS
class, too.

Note, that the EGPRS class is not yet taken from the CSN.1 RA
capability and is always set to 0. Note also, that append_data
still uses ms_class only.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 5265f59525 edge: Enable EGPRS if configured and egprs_ms_class present
Enable the TBF to use EGPRS if the bts->egprs_enabled config variable
has been set via the VTY "egprs" command and if the MS has signaled a
EGPRS multislot class.

Tell the MS to use EGPRS if the condition above holds.

Note that this will cause the MS to use EGPRS RLC block formats for
further messages which are not yet understood by the PCU.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 86b6f05d19 edge: Support EGPRS multislot class handling in tbf_alloc
Add an egprs_ms_class argument to the allocation functions and
set/pass it where necessary.

Sponsored-by: On-Waves ehf
2015-12-15 15:17:51 +01:00
Jacob Erlbeck 5643f35fb4 edge: Add m_egprs_enabled and related methods to TBF
Add the following methods to gprs_rlcmac_tbf:
  - is_egprs_enabled
  - enable_egprs
  - disable_egprs

Also show the value of the flag in name() by displaying "EGPRS" if
it is set.

Sponsored-by: On-Waves ehf
2015-12-15 15:17:51 +01:00
Jacob Erlbeck 76d767cbe8 edge: Support EGPRS in packet uplink assignment message
Currently the Encoding::write_packet_uplink_assignment method only
supports the GPRS variant of the message.

This commit adds the missing EGPRS variant to the encoder.

Sponsored-by: On-Waves ehf
2015-11-30 12:20:36 +01:00
Jacob Erlbeck 953c78987a edge: Add egprs config command
Add a global config flag to enable the use EDGE/EGPRS.

The following VTY commands are added to node config-pcu:

 - egprs              Enables EGPRS
 - no egprs           Disable EGPRS

Note that enabling EGPRS is experimental and will most likely break
packet transmission until a minimal required set of EGPRS
functionality is implemented.

Sponsored-by: On-Waves ehf
2015-11-30 12:20:36 +01:00
Jacob Erlbeck c3c58046c7 edge: Get EGPRS multislot class
The EGPRS MS class ist contained in the MS_RA_capability information.
Its presence indicates, that the MS is able (and willing) to use
EGPRS.

This commit implements basic support for retrieving, storing, and
showing it in the VTY. The information is stored in the MS object.

Sponsored-by: On-Waves ehf
2015-11-30 12:20:36 +01:00
Jacob Erlbeck 111ebe84c2 Revert "pcu: Improve default config"
This reverts commit acfb883011.

The values are now the default values of the application, so they
do not need to be set in this file.

Sponsored-by: On-Waves ehf
2015-11-30 12:11:48 +01:00
Jacob Erlbeck eb93f592e5 pcu: Enable dl-tbf-idle-time and idle-ack-delay by default
Currently these are enabled in the default config file. Since CoDel
is enabled by default in main() but should not be used without at
least dl-tbf-idle-time, the current default config may lead to
packet loss and performance problems.

This commit enables both features to provide a good (GPRS) performance
experience even without a configuration.

Sponsored-by: On-Waves ehf
2015-11-30 12:11:39 +01:00
Jacob Erlbeck f5898a0528 stat: Add global stat group
Add a global stat_item group for measurement values and a
corresponding macro to get and set the values.
Add a stat_item STAT_MS_PRESET to monitor the number of
MS objects in the storage.

Sponsored-by: On-Waves ehf
2015-11-30 12:11:29 +01:00
Jacob Erlbeck edfd7e3d94 encoder: Whitespace fixes
Sponsored-by: On-Waves ehf
2015-11-27 15:09:10 +01:00
Jacob Erlbeck acfb883011 pcu: Improve default config
Currently the optional features dl-tbf-idle-time and idle-ack-delay
are not enabled when using the default config. Without the former,
the packet loss is significantly increased since CoDel is enabled by
default, eventually throwing away packets from ongoing paging and TBF
establishment procedures.

This commit changes the default config for satisfactory results even
with a single PDCH.

Sponsored-by: On-Waves ehf
2015-11-27 15:09:10 +01:00
Jacob Erlbeck 42aba81c2f stats: Enable stats subsystem
Sponsored-by: On-Waves ehf
2015-11-17 15:42:01 +01:00
Harald Welte 08e5d604d3 remove obsolete OpenBTS PCU interface support
This OpenBTS socket interface was originally added to enable GPRS
capabilitie with a forked version of OpenBTS, at a time when the public
OpenBTS release didn't yet have any GPRS support.

Meanwhile, the later OpenBTS releases included their own version of
GPRS, without any external PCU/SGSN/GGSN, so this interface is no longer
needed.

This also means that the OsmoBTS socket interface is now the default at
compilation time.  There is no other interface.
2015-11-13 16:07:25 +01:00
Harald Welte 19d1e9270d osmobts_sock.cpp: Add missing space in log statement. 2015-11-12 01:08:19 +01:00
Harald Welte 218482769b print/log OpenBTS / OsmoBTS variant in PCU startup
Otherwise it can be very confusing, as Max had to figure out today...
2015-11-12 01:07:41 +01:00
Harald Welte d32cbbb130 rename sysmo_sock.cpp to osmobts_sock.cpp
This also renames the --enable-sysmbts option to --enable-osmobts

This socket interface was nevery sysmoBTS specific, but it is a generic
socket interface to any OsmoBTS supported layer1/hardware.  So it was a
mis-nomer so far.
2015-11-12 01:01:35 +01:00