Instrument TX and RX functions dealing with regular BTS (without direct
DSP access) to use GSMTAP. Previously only DSP-related functions were
instrumented.
This option allows user to use custom IP address instead of default "localhost".
Correspondingly gsmtap init moved from sysmoBTS-specific code up to "bts" struct
level. This way it can be easier reused by other implementations. The
lack of regressions was verified by checking following command on
sysmoBTS: "./osmo-pcu -c osmo-pcu.cfg -r 1 -i 192.168.10.1" where
192.168.10.1 is the host which was running wireshark and netcat:
"nc -u -l 192.168.10.1 -p 4729" to accept gsmtap flow.
This adds EDGE support and at the same time is changing a lot of code
on GPRS support as well. Due my business decision of completing as much
as possible during the time we had the unit test coverage is not as
extensive as I had hoped for.
This is just the beginning. We do not support mixed GPRS/EDGE support
and have plenty of things to improve throughput.
Thanks to On-Waves for supporting a project with so many unknowns and
uncertainty and Jacob for leading the effort at sysmocom.
Currently the MCS schemes are not supported when the leak rate is
being computed. This leads to a lower value for the leak rate, thus
limiting the throughput to GPRS-like ranges.
Use the payload size reported by GprsCodingScheme instead.
Sponsored-by: On-Waves ehf
Currently single BSN blocks of size 68 (a single unit from MCS-8)
are put into a MCS-6 block with padding according to TS 44.060
Annex J. Unfortunately, these packets are ignored by the E71. This
might be related to the currently incorrect usage of the puncturing
schemes and the RSB bit (the puncturing schemes are not updated and
the RBS flag is never set).
Avoid downgrading from MCS-8 to MCS-6 if there is no second block
available. Send the block twice instead.
Sponsored-by: On-Waves ehf
Comparing the coding scheme properties doesn't seem to be strong
enough, since create_dl_acked_block(fn, ts, index, index2) sometimes
had to combine data units of different size this way.
Check the registered size of the BSN blocks instead, since these must
match if two blocks are to be combined in a single RLC data message
with MCS7-9.
It is not yet clear, what exactly goes wrong with the current
implementation, but this commit fixes the problem which trigger the
assertion in create_dl_acked_block.
Sponsored-by: On-Waves ehf
Currently only one BSN block is encoded in each RLC data message,
even if MSC7-9 are used, which transport two independant (except for a
max BSN delta of 512) BSN blocks. In that case, the same block is
just put twice into the same message.
The current create_dl_acked_block(fn, ts) method handles
block selection (resend, new BSN, dummy block, ...) and restart
handling in one method and is too complex to extend it accordingly.
Therefore this commit move the block selection/creation handling into
a new method (take_next_bsn) which delivers the next BSN along with a
hint, whether it may be combined with another block. In that case,
the function can be called a second time (this time with a valid
previous BSN, that's the one returned by the first call) to get the
second BSN. The real block generation method
create_dl_acked_block(fn, ts, index, index2) is then called with both
BSNs as indices (the second must be -1, if there is only one BSN).
Note that every BSN returned by take_next_bsn should be passed to
create_dl_acked_block to avoid state inconsistencies.
Sponsored-by: On-Waves ehf
Currently the method is hard-coded to support a single BSN only.
MCS-7 to MCS-9 encode 2 data blocks into a single RLC data message.
This commit refactors create_dl_acked_block to process any number
of blocks internally.
Note that this does not extend the parameter list accordingly and
just duplicates the BSN if these MCS are being used.
Sponsored-by: On-Waves ehf
Currently the queue length is overwritten by the remaining chunk
length, which should be added instead. This may result in a lower
CS/MCS value than expected.
Add the chunk length instead if the TBF is present.
Sponsored-by: On-Waves ehf
Currently most offsets are hard-coded which makes it difficult to
access the data units and their headers when padding has to be taken
into account. These offset are already provided by the
gprs_rlc_data_info_init_ul/dl functions.
Change the encoder/decoder to use these values.
Note that some assumptions (bit alignment) are still present in the
code and checked by assertions.
Sponsored-by: On-Waves ehf
To access EGPRS data blocks, the optional padding must be taken into
account. Whether padding has been used must be dervied from the CPS
field in the header of the RLC EGPRS data message.
Add this function to decode the CPS value and extract that
information.
Sponsored-by: On-Waves ehf
The offsets of the data areas change when padding is used (see TS
44.060, 9.3.2.1 and Annex J for details).
Extend the parameter lists to pass the with_padding flag and use
that information to compute the correct offsets.
Sponsored-by: On-Waves ehf
Return the amount of optional padding bits, which is 6*8 for
MCS-3 and MCS-6 and 0 for all other coding schemes. The padding
is needed the encode 68 byte data blocks (MCS-8) with these schemes.
See TS 44.060, 9.3.2.1 and Annex J for details.
Sponsored-by: On-Waves ehf
This adds the following VTY command (config-pcu node):
- mcs <1-9> sets initial DL and UL MCS to the same value
- mcs <1-9> <1-9> sets initial DL and UL MCS separately
- no mcs sets the default values
Sponsored-by: On-Waves ehf
Currently only header type 3 (MCS-1 to MCS-4) is supported.
Add header structs to rlc.h and extend
Encoding::rlc_write_dl_data_header accordingly.
Sponsored-by: On-Waves ehf
Currently the state on the TBF is set to ASSIGN when it is created
and in general changed to FLOW when it is acknowledged by the MS. The
moment when the assignment is really transmitted to the MS (which can
take some time) is not reflected by the state. A TBF can considered
to be valid, when the assignment is received by the MS.
Add the state WAIT_ASSIGN that is entered when the assigment has been
send to the MS (more precisely: when the corresponding RTS has been
processed or the message has been sent to the BTS).
The TBF, its PDCH(s), and its TFI can be assumed to be valid, when the
TBF has a state of WAIT_ASSIGN or higher (assuming that the TBF
starting time has not been set, which is currently only done for SBA,
which are not associated with a TBF).
Note that due to queuing in the BTS there can still be a invalid
time period for immediate assignments, when the request is lingering
in the AGCH or PCH queues.
Sponsored-by: On-Waves ehf
The PACCH is specific to an MS and may change when a TBF is
established or removed (see TS 44.060, 8.1.1.2.2). For multislot
class type 2 phones, more than one timeslot may be used to transmit
RLC/MAC control messages.
Add a method that returns a set of TS which can be used for the
PACCH.
Sponsored-by: On-Waves ehf
Currently the selection of a pending control message is done round
robin. It can possibly happen, that a DL assigment is sent on a DL
TBF while an UL assignment is pending. The MS will replace the old
DL TBF in that case, so that it can no longer be used for the PACCH
so that the UL assignment is lost.
Give assigment requests for the same direction a lower priority.
Sponsored-by: On-Waves ehf
Currently the TBF whose PACCH has been used to send an assigment
is freed if it is in state WAIT_RELEASE. Sometimes this TBF could
be used for several assignments (e.g. an 'old' DL TBF is used to
assign an UL and then a DL TBF). The second of these assigments will
never be sent in that case. On the other hand, the MS replaces a
TBF of the same direction, so the old one can be freed in that case.
Only free the TBF if it is in state WAIT_RELEASE and has the same
direction like the new one.
Sponsored-by: On-Waves ehf
Tell the MS to use EGPRS if EGPRS is enabled on the TBF.
Note that only downlink TBF will be supported so far. Thus
single-phase uplink assignments may not work properly.
Sponsored-by: On-Waves ehf
The EGPRS support will need more information to encode the IMMEDIATE
ASSIGMENT. Instead of adding more parameters pass a pointer to the
TBF unless an SBA shall be done (indicated by tbf == NULL). All
values that can be derived from the TBF and are not needed for an SBA
are removed from the parameter list.
Return a negative value on error.
Sponsored-by: On-Waves ehf
Currently bitvec_write_field is used which just sets the bits as
given, while the spec 44.018 assumes LH encoding.
Use the bitvec_write_field_lh function instead.
Sponsored-by: On-Waves ehf
While the bitvec functions from libosmocore support LH encoding, the
C++ wrapper does not.
Add a bitvec_write_field_lh function that is similar to
bitvec_write_field, but writes L and H instead of ZERO and ONE.
Sponsored-by: On-Waves ehf
Currently the CCCH flag is cleared and the PACCH flag is set when a
multislot upgrade is scheduled for a downlink TBF, even if the MS has
never confirmed in any way that the PACCH really exists. This can
happen if the MS did not receive the DL IMM.ASS. Since the CCCH flags
gets cleared in that case, the IMM.ASSS is never retried and all
subsequent PACKET DOWNLINK ASSIGNMENTS will fail.
This commit delays the update of these flags until the MS has
responded with a corresponding CONTROL ACK.
Sponsored-by: On-Waves ehf
Currently the old TFI is always used as ID when a
PACKET DOWNLINK ASSIGNMENT is generated. This fails
if the old TBF has not been fully assigned yet. The
MS will then ignore the PDA.
This commit changes write_packet_downlink_assignment to accept
an additional parameter old_tfi_is_valid and uses the new TBF's
TLLI instead of the olf TFI if that parameter is set to false.
Sponsored-by: On-Waves ehf
Currently the checks for and the actual polling is done in several
places by copy & paste of several lines of code. This hinders changes
of they polling is handled internally and also is likely source of
programming mistakes.
Separate this into a check_polling function, that checks whether
polling is possible and returns the FN and the RRBP to be used in
that case. Otherwise the cause is logged (LOGL_DEBUG) and a negative
error value is returned. There are no other side effect beside the
logging.
If the call is successful, the set_polling method can be used to
actually register the polling.
Extend the encoder functions' parameters lists by an rrbp parameter.
Sponsored-by: On-Waves ehf
Currently tbf->control_ts is used to look up an incoming poll
response. Since that may eventually change, poll timeouts could
theoretically happen in that case.
Store the real poll TS in tbf->poll_ts at all places where
tbf->poll_fn is set. Do not use tbf->control_ts to look up
outstanding polls.
Sponsored-by: On-Waves ehf
Currently there are some places where tbf->control_ts != ts is
evaluated to check, whether ts is a control slot.
Replace these expressions by tbf->is_control_ts(ts) which does
the same whitout exposing internal fields.
Sponsored-by: On-Waves ehf
Currently the checks in that function are based on the different
internal TS values of a TBF. It is assumed that they match the TS
that the current RTS refers to.
This commit adds a TS parameter to create_ul_ass, create_dl_ass,
and create_ul_ack to make this more explicit.
Sponsored-by: On-Waves ehf
Currently existing TBF can be reused after an MS has sent a RACH
request. Since the MS can be or most probably is in packet idle mode
in that case, the TBF are no longer usable even if they share the
PDCHs and the control TS with the new one.
There are occasional freezes where the MS does no longer react to
messages sent on the PACCH.
This change aborts all pending TBFs if a new TBF is or has been
established via RACH.
Sponsored-by: On-Waves ehf
Currently the is a release() function which takes care of
statistics and shutdown of properly finished TBFs, but which
cannot be used for aborted TBFs.
This commit add an abort() method which handles unacked RLC blocks
as lost and doesn't start a release timer. This method will be
invoked by tbf_free() for downlink TBF.
Sponsored-by: On-Waves ehf
According to spec, the lowest numbered PDCH of the TBF shall be used
for the PACCH, only when concurrent TBF are active, the lowest common
PDCH shall be used. An immediate assigment is in general only sent,
if no TBF is active, so the latter case never applies.
This reverts commit fdd8a1ba2312be3f33576ee994c0b5da6272e815.
Make use of variables, log them to LOGL_DEBUG, and reduce code
duplication.
This should help to narrow down the cause why snd_dl_ass are not
answered by the MS sometimes.
Sponsored-by: On-Waves ehf
That IE may contain inaccurate or completely bogus data.
This commit disables the parsing.
Note that this should be replaced by a config option.
Sponsored-by: On-Waves ehf
Currently the values in the BSSGP RA Cap IE are eventually use
overwrite the 'good' values obtained from the MS earlier.
Use the 'good' values when the are present, which is assumed if
at least one of ms->ms_class() or ms->egprs_ms_class() is set.
Sponsored-by: On-Waves ehf
In case there is no MS object present that matches a DL UNITDATA,
the EGPRS class is currently assumed to be 0, since the Radio
Access Capabilities IE is not fully decoded if present.
This commit uses the CSN.1 decoder to parse the IE and uses the
same functions like the uplink related code does to get the GPRS
and EGPRS multislot classes.
Remove the old parse_ra_cap_ms_class function.
Sponsored-by: On-Waves ehf
Just keep this for later reference, since a CSN.1 decoder based
implementation will be used.
This reverts commit b37ab36bb14d2d2c1363fbe521cd19984d0c3d4c.
Add an extended parse_ra_cap function based on the existing
parse_ra_cap_ms_class which also parses up to the EGPRS related
fields.
Sponsored-by: On-Waves ehf
Currently the window size is fixed to 64 even for EGPRS.
Support dynamic window sizes depending on the number of PDCH. The
WS can be set to b + f * N_PDCH. If the result is not valid according
to TS 44.060, Table 9.1.9.2.1, the value will be corrected to use the
next lower valid value (or 64).
The following VTY commands are added (config-pcu node):
window-size <0-1024> set base (b) value and leave f unchanged
window-size <0-1024> <0-256> set base (b) and factor (f)
Sponsored-by: On-Waves ehf
Currently only the GPRS MS class and the DL CS (even for UL TBFs)
are shown.
Add the EGPRS MS class and use the TBF's real CS.
Sponsored-by: On-Waves ehf
These functions are currently defined in src/gprs_rlcmac_ts_alloc.cpp
but will be needed elsewhere.
Turn them into template functions to support different types and move
them to pcu_utils.h.
Sponsored-by: On-Waves ehf
Currently gprs_rlc_ul_window and gprs_rlc_dl_window are completely
separate classes, containing several identical members and methods.
This commit add a shared parent class containing WS and SNS handling.
Sponsored-by: On-Waves ehf
If the downlink BSSGP didn't contain a RA Capabilities IE, both
MS class values are 0. The phone will send valid RA Caps later on.
Currently in that case, the downlink TBF is not established
if EGPRS is enabled.
Just force egprs_ms_class to 1 if EGPRS (only) is enabled.
Sponsored-by: On-Waves ehf
Currently the plain 'egprs' command enables EGPRS but doesn't prevent
phones from being served in GPRS mode if they do not support EGPRS.
This involves complex frame allocation implementations in dynamic
mode, especially if 8PSK is being used. This is due to the inability
of non-EGPRS phone to decode 8PSK USF and ES/P altogether. Since
polling has a higher priority than USF, collisions will have to be
prevented by the PCU by never using an GPRS USF if it refers to a FN
that is already being used for polling.
This commit just disables mixed usage by ignoring GPRS-only request
if EGPRS is enabled.
The following VTY command (config-pcu node) is changed:
egprs -> egprs only
Sponsored-by: On-Waves ehf
Currently the coding scheme gets reset when GprsMs::set_mode()
is called even if the mode did not change.
Make sure, that the CS is only reset, if it is not compliant to the
new mode.
Sponsored-by: On-Waves ehf
The bitvec RBB is always valid, even when FINAL_ACK_INDICATION is
set. This is done by the ack/nack decoder function which fake a
bitmap starting with V(A) up to V(S)-1 in that case (see
Decoding::handle_final_ack).
Call gprs_rlcmac_dl_tbf::update_window unconditionally and only use
is_final for logging and TBF state changes in
gprs_rlcmac_dl_tbf::rcvd_dl_ack.
Sponsored-by: On-Waves ehf
The current methods are based on the GRPS specific RBB and SSN values
and formats which are not compatible with EGPRS.
Add a second set of similar methods with the same semantics but
which are based on a bitvec and the first BSN instead.
The following methods are affected:
- gprs_rlc_dl_window::update
- gprs_rlcmac_dl_tbf::rcvd_dl_ack
- gprs_rlcmac_dl_tbf::update_window
Sponsored-by: On-Waves ehf
Currently the RBB is used and passed directly to the window handling
methods. For EGPRS a more abstract bitvec is derived from the messages
and will passed around instead.
Add a similar function for GPRS so that the same window handling can
be used for GPRS and EGPRS.
Sponsored-by: On-Waves ehf
Currently CRBB bitmaps are ignored if they are present.
This commit enables the decoding.
Note that this requires osmo_t4_decode in libosmocore.
Sponsored-by: On-Waves ehf
Currently only uncompressed bitmaps (URBB) are supported in
PACKET UPLINK ACK/NACK messages.
Extend decode_egprs_acknack_bits to decode compressed bitmaps (CRBB),
too.
Note that this code is only active, if the macro WITH_CRBB_DECODING
is defined.
Sponsored-by: On-Waves ehf
Currently this message is ignored.
Support decoding and handling of this message. Use a bitvec for the
decoder that just represents a BSN sequence without any encoding
details (first bit -> first BSN). Return the corresponding BSN range
(snsmod(bsn_begin + bits_in_bitvec) = bsn_end), so snsmod(bsn_end-1)
is the last BSN if there is at least 1. If bsn_begin == bsn_end, no
BSNs has been added.
Note that this bitvec is not yet used for RBB handling. It just calls
the old rcvd_dl_ack with a faked (all bits are 1) RBB map.
Sponsored-by: On-Waves ehf
The presence of the LENGTH field adds an additional offset which
breaks the related M_SERIALIZE in gsm_rlcmac.cpp. In that case,
the Desc in EGPRS_AckNack_t is being cast to EGPRS_AckNack_w_len_t
and then ((EGPRS_AckNack_w_len_t *)Desc)->Desc is filled with the
parsed data, which is a platform dependant number of bytes apart the
real Desc struct.
Remove LENGTH field from EGPRS_AckNack_w_len_t so that the Desc field
is the first field.
Note that this is not a real fix. The rlcmac wireshark dissector
still has the same declaration but doesn't seem to suffer from this
problem.
Sponsored-by: On-Waves ehf
The MS' RLC receiver needs a valid CPS field to decode the block.
Add the function gprs_rlc_mcs_cps to generate the CPS value based on
coding scheme, puncturing, and padding.
Sponsored-by: On-Waves ehf
Currently only GPRS data block encoding is supported.
This commit adds rlc_data_to_dl_append_egprs which does the EGPRS
specific extension and chunk handling. It extends
Encoding::rlc_data_to_dl_append to use that function for MCS coding
schemes.
Sponsored-by: On-Waves ehf
Currently the GPRS data block encoding is applied to every
coding scheme, even if an MCS is selected.
This commit renames the actual encoding function to
rlc_data_to_dl_append_gprs (not exported) and puts
selection code into Encoding::rlc_data_to_dl_append. This
requires an additional cs argument.
Sponsored-by: On-Waves ehf
Currently TBF related tasks (status changes, counter updates,
LLC dummy command insertion) as well as
RLC data block generation are done within create_new_bsn.
The data block creation part has already been copied to
the stateless Encoding::rlc_data_to_dl_append function.
This commit changes create_new_bsn to use the encoder function and
just care about the TBF related stuff.
Since the rlc_data_to_dl_append function has been validated against
the test cases being described in annex B of TS 44.060, this
commit fixes an encoder bug which leads to broken LLC frames in
a special case (see example B.2, the main header's E bit was
erroneously set to 1 in that case). When this happens, the LLC frame
will get discarded after reassembly, so that TCP will have to
retransmit the lost packet.
Sponsored-by: On-Waves ehf
This function appends a single chunk to an RLC downlink data block.
The implementation is basically taken from the
gprs_rlcmac_dl_tbf::create_new_bsn method without the TBF related
functionality and any side effects.
Note that it still only supports GRPS.
Sponsored-by: On-Waves ehf
This commit removes the use of struct rlc_dl_header from
gprs_rlcmac_dl_tbf::create_dl_acked_block and
gprs_rlcmac_dl_tbf::create_new_bsn. Instead of patching the
data area directly, the RLC block encoding functions are used.
Note that the data unit encoding is still hard-coded to GPRS in
create_new_bsn, so using MCS 1-4 (albeit being supported by the
encoder) will not work yet.
Sponsored-by: On-Waves ehf
Currently the (GPRS) RLC block encoding is done by setting the
header fields directly in gprs_rlcmac_dl_tbf::create_new_bsn.
This is much more complex with EGPRS, since the data fields are
not byte aligned, the header formats depend on the header type,
and the mapping of bits to bytes is LSB first.
This commit adds Encoding::rlc_write_dl_data_header which writes
the header according to the given gprs_rlc_data_header structure.
Encoding::rlc_copy_from_aligned_buffer is also added to copy
byte sequences into the message.
Note that the actual encoding of data units is not yet present.
Sponsored-by: On-Waves ehf
Add the functions gprs_rlc_data_info_init_dl/ul which initialise a
gprs_rlc_data_info structure depending on the coding scheme. The
fields num_data_blocks, data_offs_bits, cs, and the data_blocks are
valid after this call. The other fields are set to 0.
The data blocks are initialised to the correct data_len, e == 1
(no extension header field), cv == 15 (not a final block). The other
data block fields are set to 0.
The gprs_rlc_data_block_info can also be initialised separately
by using the gprs_rlc_data_block_info_init function.
Sponsored-by: On-Waves ehf
Currently the RLC message length that is obtained from the DSP is
reduced by 1 if the last byte of the buffer includes spare bits.
While this worked well with GPRS, these bits are being used to
encode RLC blocks in EGPRS mode. Thus this last byte must not be
chopped off. The functionality of the code is not affected by this,
since the modified length value is not used.
This commit adds GprsCodingScheme::usedSizeDL/UL to return
the number of bytes needed to encode the message block. If there are
single bits at the end that are to be used (EGPRS), the functions
return the number of full bytes plus 1 (which is the buffer size
reported by the DSP and returned by sizeUL/sizeDL). The commit also
removes the len parameter from rcv_data_block_acknowledged.
Sponsored-by: On-Waves ehf
These struct names are more specific than necessary. They are used
for GPRS (uplink) already. In downlink direction, only a few fields
will be added to the header struct. Add addition,
gprs_rlc_ul_header_egprs does not map directly to an encoded
header, like many other 'header' structs do.
Change the names to fit both modes and both directions:
gprs_rlc_ul_header_egprs -> gprs_rlc_data_info
gprs_rlc_ul_data_block_info -> gprs_rlc_data_block_info
Sponsored-by: On-Waves ehf
The EGPRS multi-slot class need to be parsed from the CSN.1 RA
capability (see gprs_bssgp_pcu_rx_dl_ud).
This commit adds a workaround to get the EGPRS MS class from the MS
object if that is present.
Sponsored-by: On-Waves ehf
Currently GPRS is always used for downlink, which violates TS 44.060
(concurrent TBF must have the same mode).
Enable EGPRS mode for downlink if the EGPRS MS class is != 0 and
EGRPS has been enabled.
Note that EGPRS Ack/Nack handling is not yet implemented, so enabling
EGPRS will not work still. But we will now get EGPRS DL ACK/NACK
messages now from the MS.
Sponsored-by: On-Waves ehf
Add an use_egprs parameter to write_packet_downlink_assignment
and add the EGPRS related fields if it is set to true. The
window size is fixed at 64 blocks, link quality measurement
reports have been disabled, and the other optional fields are not
present.
Sponsored-by: On-Waves ehf
Currently the TBF and MS object use a plain integer value
(current_cs) to manage the coding scheme. This makes it difficult to
support the MCS schemes. GprsCodingScheme supports a partial ordering
of these values (CS and MCS) and provides safe increment and
decrement methods.
Use the GprsCodingScheme type instead of integer for cs fields and
variables. Add a 'mode' to GprsMs which can be set to either GPRS,
EGPRS, or EGPRS_GMSK which also set the initial values of
current_cs_ul/dl. Select the mode based on max_mcs_ul and max_mcs_dl.
Sponsored-by: On-Waves ehf
Provide the initial MCS values for EGPRS data blocks. They are set
to 1 (MCS-1) for each direction and there is no support to change
these configuration values yet (the automatic adaption still works,
so there is probably no need to set these values).
Sponsored-by: On-Waves ehf
This sets the maximum MCS encoding used for EGPRS RLC data blocks
in either direction.
The following VTY command are added to node config-pcu:
- mcs max <1-9> set maximum for both, uplink and downlink
- mcs max <1-9> <1-9> set maximum for downlink and uplink (in that
order)
- no mcs max do not limit
Note that using a value of 4 or below for each direction implies
that a GMSK-only TBF may be assumed, which for instance would allow
the use of the GPRS MS class instead of the possibly more restrictive
EGPRS MS class.
Sponsored-by: On-Waves ehf
LListHead does basically the same like llist_pods, but more C++ish
and with type safety.
This commit turns the former list field of gprs_rlcmac_tbf into a
private field, provides accessors, moves the related code from
pcu_vty.c to pcu_vty_functions.cpp, and removes the llist_pods
type and related code.
Sponsored-by: On-Waves ehf
This function is similar to the show_ms function already present in
the target file. Since the TBF lists will be turned into LListHead
based lists, they will get an iteration function in
pcu_vty_functions.cpp, too.
Sponsored-by: On-Waves ehf
Currently casts from gprs_rlcmac_tbf to gprs_rlcmac_ul_tbf and
gprs_rlcmac_dl_tbf are done by using static_cast. This doesn't provide
protection against converting a gprs_rlcmac_ul_tbf pointer to a
gprs_rlcmac_dl_tbf pointer and vice versa.
This commit provides two functions as_ul_tbf and as_dl_tbf, that
behave similar like dynamic_cast but use the direction field instead
of RTTI.
Sponsored-by: On-Waves ehf
The current write_packet_uplink_ack implementation is based on the
CSN.1 encoder which makes it difficult to do the bitmap encoding for
EGPRS.
Add a new implementation based on bitvec functions to create the
PACKET UPLINK ACK/NACK messages.
Sponsored-by: On-Waves ehf
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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.
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.
The leak rate sent to the SGSN does not reflect the current CS level,
lost frames, and control message overhead. So the SGSN cannot do
proper queue control under non-optimal conditions.
This commit computes the leak rate for the last flow control interval
by computing the maximum theoretical leak rate and basically
substracting control blocks, nacked blocks, and reduced block sizes
due to CS downgrade. By using this approach, the value will by more
stable on low load, where the value will tend to be near the value
derived from the configuration. On full load the transmitted value is
completely derived from the measurements.
Note that the MS default values are no adapted to the adapted BVC
leak rate, since a single MS which has a lower link quality would
otherwise be reducing the rate of another MS with good radio
conditions, which would not make much sense if they did not share any
PDCH.
Sponsored-by: On-Waves ehf
When a timeout has occured several times, the procedures handled by
poll_timeout are aborted. This happens when the number of repetitions
exceed N3105. Currently only the timeouts themselves are counted.
This commits adds counters that are incremented if a procedure has
really failed.
New counter:
- rlc.ass.failed: Count failing UL and DL assigments via PACCH
- rlc.ack.failed: Count failing DL Ack/Nack requests
Sponsored-by: On-Waves ehf
Currently an existing DL TBF can get lost in the process of
establishing an UL TBF via RACH. This can lead to stalled connections
until the network sends more LLC frames.
This commit adds a check for a non-empty LLC queue after the UL TBF
has been established to rcv_control_ack (GPRS_RLCMAC_UL_ASS_WAIT_ACK
path) to eventually establish a new DL TBF on the UL TBF's PACCH.
Sponsored-by: On-Waves ehf
Currently an existing DL TBF is freed immediately, when a resource
request is received. This makes sense since the MS might have dropped
it when switching to the PDCH signaled via the AGCH for the SBA. But
if the TBF still is assumed to exist on the MS side, there might be
TFI collisions if the old TBF object is not kept to block its TFI
for some time.
This commit changes rcv_resource_request to call release() instead of
tbf_free() on the DL TBF object (if it exists).
Sponsored-by: On-Waves ehf
Currently reuse_tbf (partly) resets the old DL TBF and uses its PACCH
to establish a new DL TBF. The method can not be used with UL TBFs.
This commit replaces the reuse_tbf method into a
gprs_rlcmac_dl_tbf:release method which triggers the TBF's timer
based deletion (so that the TFI is still reserved for some time) and
a gprs_rlcmac_tbf::establish_dl_tbf_on_pacch which can establish DL
TBFs on existing PACCHs of either DL or UL TBFs.
Sponsored-by: On-Waves ehf
Currently when a second MS object has been created for an MS, because
the TLLI was not known yet, the will be detected in
gprs_rlcmac_tbf::extract_tlli and the two objects will be merged by
update_ms. But when the dl_tbf is moved from the old to the new
(second) MS object, the old MS object can get idle and be removed
before the object are merged. This can cause LLC frame loss when the
MS object is deleted immediately after getting idle (no timeout
configured).
This commit adds a guard to keep the MS object until extract_tlli has
been executed.
Sponsored-by: On-Waves ehf
This reverts commit e91bd3babd.
That commit seems to cause hanging DL TBFs when there was a RACH
based UL TBF establishment while it that TBF is active. This could be
caused by the use of a different PDCH for the SBA.
Conflicts:
tests/tbf/TbfTest.cpp
tests/tbf/TbfTest.err
Max
Harald Welte