/* Copied from tbf.cpp * * Copyright (C) 2012 Ivan Klyuchnikov * Copyright (C) 2012 Andreas Eversberg * Copyright (C) 2013 by Holger Hans Peter Freyther * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include #include #include #include #include #include #include #include #include #include "pcu_utils.h" extern "C" { #include #include #include } #include #include #include /* After sending these frames, we poll for ack/nack. */ #define POLL_ACK_AFTER_FRAMES 20 static inline void tbf_update_ms_class(struct gprs_rlcmac_tbf *tbf, const uint8_t ms_class) { if (!tbf->ms_class() && ms_class) tbf->set_ms_class(ms_class); } static void llc_timer_cb(void *_tbf) { struct gprs_rlcmac_dl_tbf *tbf = (struct gprs_rlcmac_dl_tbf *)_tbf; if (tbf->state_is_not(GPRS_RLCMAC_FLOW)) return; LOGP(DRLCMAC, LOGL_DEBUG, "%s LLC receive timeout, requesting DL ACK\n", tbf_name(tbf)); tbf->request_dl_ack(); } void gprs_rlcmac_dl_tbf::cleanup() { osmo_timer_del(&m_llc_timer); } void gprs_rlcmac_dl_tbf::start_llc_timer() { if (bts_data()->llc_idle_ack_csec > 0) { struct timeval tv; /* TODO: this ought to be within a constructor */ m_llc_timer.data = this; m_llc_timer.cb = &llc_timer_cb; csecs_to_timeval(bts_data()->llc_idle_ack_csec, &tv); osmo_timer_schedule(&m_llc_timer, tv.tv_sec, tv.tv_usec); } } int gprs_rlcmac_dl_tbf::append_data(const uint8_t ms_class, const uint16_t pdu_delay_csec, const uint8_t *data, const uint16_t len) { LOGP(DRLCMAC, LOGL_INFO, "%s append\n", tbf_name(this)); gprs_llc_queue::MetaInfo info; struct msgb *llc_msg = msgb_alloc(len, "llc_pdu_queue"); if (!llc_msg) return -ENOMEM; gprs_llc_queue::calc_pdu_lifetime(bts, pdu_delay_csec, &info.expire_time); gettimeofday(&info.recv_time, NULL); memcpy(msgb_put(llc_msg, len), data, len); llc_queue()->enqueue(llc_msg, &info); tbf_update_ms_class(this, ms_class); start_llc_timer(); if (state_is(GPRS_RLCMAC_WAIT_RELEASE)) { LOGP(DRLCMAC, LOGL_DEBUG, "%s in WAIT RELEASE state " "(T3193), so reuse TBF\n", tbf_name(this)); tbf_update_ms_class(this, ms_class); establish_dl_tbf_on_pacch(); } return 0; } static int tbf_new_dl_assignment(struct gprs_rlcmac_bts *bts, const char *imsi, const uint32_t tlli, const uint32_t tlli_old, const uint8_t ms_class, const uint8_t egprs_ms_class, struct gprs_rlcmac_dl_tbf **tbf) { uint8_t ss; int8_t use_trx; uint16_t ta = GSM48_TA_INVALID; struct gprs_rlcmac_ul_tbf *ul_tbf = NULL, *old_ul_tbf; struct gprs_rlcmac_dl_tbf *dl_tbf = NULL; GprsMs *ms; /* check for uplink data, so we copy our informations */ #warning "Do the same look up for IMSI, TLLI and OLD_TLLI" #warning "Refactor the below lines... into a new method" ms = bts->bts->ms_store().get_ms(tlli, tlli_old, imsi); if (ms) { ul_tbf = ms->ul_tbf(); ta = ms->ta(); } /* TODO: if (!ms) create MS before tbf_alloc is called? */ if (ul_tbf && ul_tbf->m_contention_resolution_done && !ul_tbf->m_final_ack_sent) { use_trx = ul_tbf->trx->trx_no; ss = 0; old_ul_tbf = ul_tbf; } else { use_trx = -1; ss = 1; /* PCH assignment only allows one timeslot */ old_ul_tbf = NULL; } // Create new TBF (any TRX) #warning "Copy and paste with alloc_ul_tbf" /* set number of downlink slots according to multislot class */ dl_tbf = tbf_alloc_dl_tbf(bts, ms, use_trx, ms_class, egprs_ms_class, ss); if (!dl_tbf) { LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource\n"); return -EBUSY; } dl_tbf->update_ms(tlli, GPRS_RLCMAC_DL_TBF); dl_tbf->ms()->set_ta(ta); LOGP(DRLCMAC, LOGL_DEBUG, "%s [DOWNLINK] START\n", tbf_name(dl_tbf)); /* Store IMSI for later look-up and PCH retransmission */ dl_tbf->assign_imsi(imsi); /* trigger downlink assignment and set state to ASSIGN. * we don't use old_downlink, so the possible uplink is used * to trigger downlink assignment. if there is no uplink, * AGCH is used. */ dl_tbf->bts->trigger_dl_ass(dl_tbf, old_ul_tbf); *tbf = dl_tbf; return 0; } /** * TODO: split into unit test-able parts... */ int gprs_rlcmac_dl_tbf::handle(struct gprs_rlcmac_bts *bts, const uint32_t tlli, const uint32_t tlli_old, const char *imsi, uint8_t ms_class, uint8_t egprs_ms_class, const uint16_t delay_csec, const uint8_t *data, const uint16_t len) { struct gprs_rlcmac_dl_tbf *dl_tbf = NULL; int rc; GprsMs *ms, *ms_old; /* check for existing TBF */ ms = bts->bts->ms_store().get_ms(tlli, tlli_old, imsi); if (ms) { dl_tbf = ms->dl_tbf(); /* If we known the GPRS/EGPRS MS class, use it */ if (ms->ms_class() || ms->egprs_ms_class()) { ms_class = ms->ms_class(); egprs_ms_class = ms->egprs_ms_class(); } } if (ms && strlen(ms->imsi()) == 0) { ms_old = bts->bts->ms_store().get_ms(0, 0, imsi); if (ms_old && ms_old != ms) { /* The TLLI has changed (RAU), so there are two MS * objects for the same MS */ LOGP(DRLCMAC, LOGL_NOTICE, "There is a new MS object for the same MS: " "(0x%08x, '%s') -> (0x%08x, '%s')\n", ms_old->tlli(), ms_old->imsi(), ms->tlli(), ms->imsi()); GprsMs::Guard guard_old(ms_old); if (!dl_tbf && ms_old->dl_tbf()) { LOGP(DRLCMAC, LOGL_NOTICE, "%s IMSI %s: " "moving DL TBF to new MS object\n", ms_old->dl_tbf()->name(), imsi); dl_tbf = ms_old->dl_tbf(); /* Move the DL TBF to the new MS */ dl_tbf->set_ms(ms); } /* Clean up the old MS object */ /* TODO: Put this into a separate function, use timer? */ if (ms_old->ul_tbf() && ms_old->ul_tbf()->T == 0) tbf_free(ms_old->ul_tbf()); if (ms_old->dl_tbf() && ms_old->dl_tbf()->T == 0) tbf_free(ms_old->dl_tbf()); ms->merge_old_ms(ms_old); } } if (!dl_tbf) { rc = tbf_new_dl_assignment(bts, imsi, tlli, tlli_old, ms_class, egprs_ms_class, &dl_tbf); if (rc < 0) return rc; } /* TODO: ms_class vs. egprs_ms_class is not handled here */ rc = dl_tbf->append_data(ms_class, delay_csec, data, len); dl_tbf->update_ms(tlli, GPRS_RLCMAC_DL_TBF); dl_tbf->assign_imsi(imsi); return rc; } struct msgb *gprs_rlcmac_dl_tbf::llc_dequeue(bssgp_bvc_ctx *bctx) { struct msgb *msg; struct timeval tv_now, tv_now2; uint32_t octets = 0, frames = 0; struct timeval hyst_delta = {0, 0}; const unsigned keep_small_thresh = 60; const gprs_llc_queue::MetaInfo *info; if (bts_data()->llc_discard_csec) csecs_to_timeval(bts_data()->llc_discard_csec, &hyst_delta); gettimeofday(&tv_now, NULL); timeradd(&tv_now, &hyst_delta, &tv_now2); while ((msg = llc_queue()->dequeue(&info))) { const struct timeval *tv_disc = &info->expire_time; const struct timeval *tv_recv = &info->recv_time; gprs_bssgp_update_queue_delay(tv_recv, &tv_now); if (ms() && ms()->codel_state()) { int bytes = llc_queue()->octets(); if (gprs_codel_control(ms()->codel_state(), tv_recv, &tv_now, bytes)) goto drop_frame; } /* Is the age below the low water mark? */ if (!gprs_llc_queue::is_frame_expired(&tv_now2, tv_disc)) break; /* Is the age below the high water mark */ if (!gprs_llc_queue::is_frame_expired(&tv_now, tv_disc)) { /* Has the previous message not been dropped? */ if (frames == 0) break; /* Hysteresis mode, try to discard LLC messages until * the low water mark has been reached */ /* Check whether to abort the hysteresis mode */ /* Is the frame small, perhaps only a TCP ACK? */ if (msg->len <= keep_small_thresh) break; /* Is it a GMM message? */ if (!gprs_llc::is_user_data_frame(msg->data, msg->len)) break; } bts->llc_timedout_frame(); drop_frame: frames++; octets += msg->len; msgb_free(msg); bts->llc_dropped_frame(); continue; } if (frames) { LOGP(DRLCMACDL, LOGL_NOTICE, "%s Discarding LLC PDU " "because lifetime limit reached, " "count=%u new_queue_size=%zu\n", tbf_name(this), frames, llc_queue()->size()); if (frames > 0xff) frames = 0xff; if (octets > 0xffffff) octets = 0xffffff; if (bctx) bssgp_tx_llc_discarded(bctx, tlli(), frames, octets); } return msg; } bool gprs_rlcmac_dl_tbf::restart_bsn_cycle() { /* If V(S) == V(A) and finished state, we would have received * acknowledgement of all transmitted block. In this case we would * have transmitted the final block, and received ack from MS. But in * this case we did not receive the final ack indication from MS. This * should never happen if MS works correctly. */ if (m_window.window_empty()) { LOGP(DRLCMACDL, LOGL_DEBUG, "- MS acked all blocks\n"); return false; } /* cycle through all unacked blocks */ int resend = m_window.mark_for_resend(); /* At this point there should be at least one unacked block * to be resent. If not, this is an software error. */ if (resend == 0) { LOGP(DRLCMACDL, LOGL_ERROR, "Software error: " "There are no unacknowledged blocks, but V(A) " " != V(S). PLEASE FIX!\n"); return false; } return true; } int gprs_rlcmac_dl_tbf::take_next_bsn(uint32_t fn, int previous_bsn, bool *may_combine) { int bsn; int data_len2, force_data_len = -1; GprsCodingScheme force_cs; bsn = m_window.resend_needed(); if (previous_bsn >= 0) { force_cs = m_rlc.block(previous_bsn)->cs_current_trans; if (!force_cs.isEgprs()) return -1; force_data_len = m_rlc.block(previous_bsn)->len; } if (bsn >= 0) { if (previous_bsn == bsn) return -1; if (previous_bsn >= 0 && m_window.mod_sns(bsn - previous_bsn) > RLC_EGPRS_MAX_BSN_DELTA) return -1; if (is_egprs_enabled()) { /* Table 8.1.1.2 and Table 8.1.1.1 of 44.060 */ m_rlc.block(bsn)->cs_current_trans = GprsCodingScheme::get_retx_mcs( m_rlc.block(bsn)->cs_init, ms()->current_cs_dl(), bts->bts_data()->dl_arq_type); LOGP(DRLCMACDL, LOGL_DEBUG, "- initial_cs_dl(%d) last_mcs(%d)" " demanded_mcs(%d) cs_trans(%d)" " arq_type(%d) bsn(%d)\n", m_rlc.block(bsn)->cs_init.to_num(), m_rlc.block(bsn)->cs_last.to_num(), ms()->current_cs_dl().to_num(), m_rlc.block(bsn)->cs_current_trans.to_num(), bts->bts_data()->dl_arq_type, bsn); /* TODO: Need to remove this check when MCS-8 -> MCS-6 * transistion is handled. * Refer commit be881c028fc4da00c4046ecd9296727975c206a3 */ if (m_rlc.block(bsn)->cs_init == GprsCodingScheme::MCS8) m_rlc.block(bsn)->cs_current_trans = GprsCodingScheme::MCS8; } else m_rlc.block(bsn)->cs_current_trans = m_rlc.block(bsn)->cs_last; data_len2 = m_rlc.block(bsn)->len; if (force_data_len > 0 && force_data_len != data_len2) return -1; LOGP(DRLCMACDL, LOGL_DEBUG, "- Resending BSN %d\n", bsn); /* re-send block with negative aknowlegement */ m_window.m_v_b.mark_unacked(bsn); bts->rlc_resent(); } else if (state_is(GPRS_RLCMAC_FINISHED)) { LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " "because all blocks have been transmitted.\n", m_window.v_a()); bts->rlc_restarted(); if (restart_bsn_cycle()) return take_next_bsn(fn, previous_bsn, may_combine); } else if (dl_window_stalled()) { LOGP(DRLCMACDL, LOGL_NOTICE, "- Restarting at BSN %d, " "because the window is stalled.\n", m_window.v_a()); bts->rlc_stalled(); if (restart_bsn_cycle()) return take_next_bsn(fn, previous_bsn, may_combine); } else if (have_data()) { GprsCodingScheme new_cs; /* New blocks may be send */ new_cs = force_cs ? force_cs : current_cs(); LOGP(DRLCMACDL, LOGL_DEBUG, "- Sending new block at BSN %d, CS=%s\n", m_window.v_s(), new_cs.name()); bsn = create_new_bsn(fn, new_cs); } else if (!m_window.window_empty()) { LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " "because all blocks have been transmitted (FLOW).\n", m_window.v_a()); bts->rlc_restarted(); if (restart_bsn_cycle()) return take_next_bsn(fn, previous_bsn, may_combine); } else { /* Nothing left to send, create dummy LLC commands */ LOGP(DRLCMACDL, LOGL_DEBUG, "- Sending new dummy block at BSN %d, CS=%s\n", m_window.v_s(), current_cs().name()); bsn = create_new_bsn(fn, current_cs()); /* Don't send a second block, so don't set cs_current_trans */ } if (bsn < 0) { /* we just send final block again */ LOGP(DRLCMACDL, LOGL_DEBUG, "- Nothing else to send, Re-transmit final block!\n"); bsn = m_window.v_s_mod(-1); bts->rlc_resent(); } *may_combine = m_rlc.block(bsn)->cs_current_trans.numDataBlocks() > 1; return bsn; } /* * Create DL data block * The messages are fragmented and forwarded as data blocks. */ struct msgb *gprs_rlcmac_dl_tbf::create_dl_acked_block(uint32_t fn, uint8_t ts) { int bsn, bsn2 = -1; bool may_combine; LOGP(DRLCMACDL, LOGL_DEBUG, "%s downlink (V(A)==%d .. " "V(S)==%d)\n", tbf_name(this), m_window.v_a(), m_window.v_s()); bsn = take_next_bsn(fn, -1, &may_combine); if (bsn < 0) return NULL; if (may_combine) bsn2 = take_next_bsn(fn, bsn, &may_combine); return create_dl_acked_block(fn, ts, bsn, bsn2); } void gprs_rlcmac_dl_tbf::schedule_next_frame() { struct msgb *msg; if (m_llc.frame_length() != 0) return; /* dequeue next LLC frame, if any */ msg = llc_dequeue(gprs_bssgp_pcu_current_bctx()); if (!msg) return; LOGP(DRLCMACDL, LOGL_INFO, "- Dequeue next LLC for %s (len=%d)\n", tbf_name(this), msg->len); m_llc.put_frame(msg->data, msg->len); bts->llc_frame_sched(); msgb_free(msg); m_last_dl_drained_fn = -1; } int gprs_rlcmac_dl_tbf::create_new_bsn(const uint32_t fn, GprsCodingScheme cs) { uint8_t *data; gprs_rlc_data *rlc_data; const uint16_t bsn = m_window.v_s(); gprs_rlc_data_block_info *rdbi; int num_chunks = 0; int write_offset = 0; Encoding::AppendResult ar; if (m_llc.frame_length() == 0) schedule_next_frame(); OSMO_ASSERT(cs.isValid()); /* length of usable data block (single data unit w/o header) */ const uint8_t block_data_len = cs.maxDataBlockBytes(); /* now we still have untransmitted LLC data, so we fill mac block */ rlc_data = m_rlc.block(bsn); data = rlc_data->prepare(block_data_len); rlc_data->cs_last = cs; rlc_data->cs_current_trans = cs; /* Initialise the variable related to DL SPB */ rlc_data->spb_status.block_status_dl = EGPRS_RESEG_DL_DEFAULT; rlc_data->cs_init = cs; rlc_data->len = block_data_len; rdbi = &(rlc_data->block_info); memset(rdbi, 0, sizeof(*rdbi)); rdbi->data_len = block_data_len; rdbi->cv = 15; /* Final Block Indicator, set late, if true */ rdbi->bsn = bsn; /* Block Sequence Number */ rdbi->e = 1; /* Extension bit, maybe set later (1: no extension) */ do { bool is_final; int payload_written = 0; if (m_llc.frame_length() == 0) { /* nothing to sent - delay the release of the TBF */ int space = block_data_len - write_offset; /* A header will need to by added, so we just need * space-1 octets */ m_llc.put_dummy_frame(space - 1); /* The data just drained, store the current fn */ if (m_last_dl_drained_fn < 0) m_last_dl_drained_fn = fn; /* It is not clear, when the next real data will * arrive, so request a DL ack/nack now */ request_dl_ack(); LOGP(DRLCMACDL, LOGL_DEBUG, "-- Empty chunk, " "added LLC dummy command of size %d, " "drained_since=%d\n", m_llc.frame_length(), frames_since_last_drain(fn)); } is_final = llc_queue()->size() == 0 && !keep_open(fn); ar = Encoding::rlc_data_to_dl_append(rdbi, cs, &m_llc, &write_offset, &num_chunks, data, is_final, &payload_written); if (payload_written > 0) bts->rlc_dl_payload_bytes(payload_written); if (ar == Encoding::AR_NEED_MORE_BLOCKS) break; LOGP(DRLCMACDL, LOGL_INFO, "Complete DL frame for %s" "len=%d\n", tbf_name(this), m_llc.frame_length()); gprs_rlcmac_dl_bw(this, m_llc.frame_length()); bts->llc_dl_bytes(m_llc.frame_length()); m_llc.reset(); if (is_final) { request_dl_ack(); set_state(GPRS_RLCMAC_FINISHED); } /* dequeue next LLC frame, if any */ schedule_next_frame(); } while (ar == Encoding::AR_COMPLETED_SPACE_LEFT); LOGP(DRLCMACDL, LOGL_DEBUG, "data block (BSN %d, %s): %s\n", bsn, rlc_data->cs_last.name(), osmo_hexdump(rlc_data->block, block_data_len)); /* raise send state and set ack state array */ m_window.m_v_b.mark_unacked(bsn); m_window.increment_send(); return bsn; } struct msgb *gprs_rlcmac_dl_tbf::create_dl_acked_block( const uint32_t fn, const uint8_t ts, int index, int index2) { uint8_t *msg_data; struct msgb *dl_msg; unsigned msg_len; bool need_poll; /* TODO: support MCS-7 - MCS-9, where data_block_idx can be 1 */ unsigned int data_block_idx = 0; unsigned int rrbp; uint32_t new_poll_fn; int rc; bool is_final = false; gprs_rlc_data_info rlc; GprsCodingScheme cs; int bsns[ARRAY_SIZE(rlc.block_info)]; unsigned num_bsns; enum egprs_puncturing_values punct[ARRAY_SIZE(rlc.block_info)]; bool need_padding = false; enum egprs_rlcmac_dl_spb spb = EGPRS_RLCMAC_DL_NO_RETX; unsigned int spb_status = get_egprs_dl_spb_status(index); /* * TODO: This is an experimental work-around to put 2 BSN into * MSC-7 to MCS-9 encoded messages. It just sends the same BSN * twice in the block. The cs should be derived from the TBF's * current CS such that both BSNs (that must be compatible) can * be put into the data area, even if the resulting CS is higher than * the current limit. */ cs = m_rlc.block(index)->cs_current_trans; GprsCodingScheme &cs_init = m_rlc.block(index)->cs_init; bsns[0] = index; num_bsns = 1; if (index2 >= 0) { bsns[num_bsns] = index2; num_bsns += 1; } /* * if the intial mcs is 8 and retransmission mcs is either 6 or 3 * we have to include the padding of 6 octets in first segment */ if ((GprsCodingScheme::Scheme(cs_init) == GprsCodingScheme::MCS8) && (GprsCodingScheme::Scheme(cs) == GprsCodingScheme::MCS6 || GprsCodingScheme::Scheme(cs) == GprsCodingScheme::MCS3)) { if (spb_status == EGPRS_RESEG_DL_DEFAULT || spb_status == EGPRS_RESEG_SECOND_SEG_SENT) need_padding = true; } else if (num_bsns == 1) { /* TODO: remove the conditional when MCS-6 padding isn't * failing to be decoded by MEs anymore */ /* TODO: support of MCS-8 -> MCS-6 transition should be * handled * Refer commit be881c028fc4da00c4046ecd9296727975c206a3 * dated 2016-02-07 23:45:40 (UTC) */ if (cs != GprsCodingScheme(GprsCodingScheme::MCS8)) cs.decToSingleBlock(&need_padding); } spb = get_egprs_dl_spb(index); LOGP(DRLCMACDL, LOGL_DEBUG, "- need_padding %d spb_status %d spb %d" "(BSN1 %d BSN2 %d)\n", need_padding, spb_status, spb, index, index2); gprs_rlc_data_info_init_dl(&rlc, cs, need_padding, spb); rlc.usf = 7; /* will be set at scheduler */ rlc.pr = 0; /* FIXME: power reduction */ rlc.tfi = m_tfi; /* TFI */ /* return data block(s) as message */ msg_len = cs.sizeDL(); dl_msg = msgb_alloc(msg_len, "rlcmac_dl_data"); if (!dl_msg) return NULL; msg_data = msgb_put(dl_msg, msg_len); OSMO_ASSERT(rlc.num_data_blocks <= ARRAY_SIZE(rlc.block_info)); OSMO_ASSERT(rlc.num_data_blocks > 0); /* Copy block(s) to RLC message */ for (data_block_idx = 0; data_block_idx < rlc.num_data_blocks; data_block_idx++) { int bsn; uint8_t *block_data; gprs_rlc_data_block_info *rdbi, *block_info; enum egprs_rlc_dl_reseg_bsn_state reseg_status; /* Check if there are more blocks than BSNs */ if (data_block_idx < num_bsns) bsn = bsns[data_block_idx]; else bsn = bsns[0]; /* Get current puncturing scheme from block */ m_rlc.block(bsn)->next_ps = gprs_get_punct_scheme( m_rlc.block(bsn)->next_ps, m_rlc.block(bsn)->cs_last, cs, spb); if (cs.isEgprs()) { OSMO_ASSERT(m_rlc.block(bsn)->next_ps >= EGPRS_PS_1); OSMO_ASSERT(m_rlc.block(bsn)->next_ps <= EGPRS_PS_3); } punct[data_block_idx] = m_rlc.block(bsn)->next_ps; rdbi = &rlc.block_info[data_block_idx]; block_info = &m_rlc.block(bsn)->block_info; /* * get data and header from current block * function returns the reseg status */ reseg_status = egprs_dl_get_data(bsn, &block_data); m_rlc.block(bsn)->spb_status.block_status_dl = reseg_status; /* * If it is first segment of the split block set the state of * bsn to nacked. If it is the first segment dont update the * next ps value of bsn. since next segment also needs same cps */ if (spb == EGPRS_RLCMAC_DL_FIRST_SEG) m_window.m_v_b.mark_nacked(bsn); else { /* * TODO: Need to handle 2 same bsns * in header type 1 */ gprs_update_punct_scheme(&m_rlc.block(bsn)->next_ps, cs); } m_rlc.block(bsn)->cs_last = cs; rdbi->e = block_info->e; rdbi->cv = block_info->cv; rdbi->bsn = bsn; is_final = is_final || rdbi->cv == 0; LOGP(DRLCMACDL, LOGL_DEBUG, "- Copying data unit %d (BSN %d)\n", data_block_idx, bsn); Encoding::rlc_copy_from_aligned_buffer(&rlc, data_block_idx, msg_data, block_data); } OSMO_ASSERT(ARRAY_SIZE(punct) >= 2); rlc.cps = gprs_rlc_mcs_cps(cs, punct[0], punct[1], need_padding); /* If the TBF has just started, relate frames_since_last_poll to the * current fn */ if (m_last_dl_poll_fn < 0) m_last_dl_poll_fn = fn; need_poll = state_flags & (1 << GPRS_RLCMAC_FLAG_TO_DL_ACK); /* poll after POLL_ACK_AFTER_FRAMES frames, or when final block is tx. */ if (m_tx_counter >= POLL_ACK_AFTER_FRAMES || m_dl_ack_requested || need_poll) { if (m_dl_ack_requested) { LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " "polling, because is was requested explicitly " "(e.g. first final block sent).\n"); } else if (need_poll) { LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " "polling, because polling timed out.\n"); } else { LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " "polling, because %d blocks sent.\n", POLL_ACK_AFTER_FRAMES); } rc = check_polling(fn, ts, &new_poll_fn, &rrbp); if (rc >= 0) { set_polling(new_poll_fn, ts); LOGP(DRLCMACDL, LOGL_DEBUG, "Polling scheduled in this " "TS %d\n", ts); m_tx_counter = 0; /* start timer whenever we send the final block */ if (is_final) tbf_timer_start(this, 3191, bts_data()->t3191, 0); /* Clear poll timeout flag */ state_flags &= ~(1 << GPRS_RLCMAC_FLAG_TO_DL_ACK); /* Clear request flag */ m_dl_ack_requested = false; /* set polling in header */ rlc.rrbp = rrbp; rlc.es_p = 1; /* Polling */ m_last_dl_poll_fn = poll_fn; LOGP(DRLCMACDL, LOGL_INFO, "%s Scheduled Ack/Nack polling on FN=%d, TS=%d\n", name(), poll_fn, poll_ts); } } Encoding::rlc_write_dl_data_header(&rlc, msg_data); LOGP(DRLCMACDL, LOGL_DEBUG, "msg block (BSN %d, %s%s): %s\n", index, cs.name(), need_padding ? ", padded" : "", msgb_hexdump(dl_msg)); /* Increment TX-counter */ m_tx_counter++; return dl_msg; } static uint16_t bitnum_to_bsn(int bitnum, uint16_t ssn) { return ssn - 1 - bitnum; } int gprs_rlcmac_dl_tbf::analyse_errors(char *show_rbb, uint8_t ssn, ana_result *res) { gprs_rlc_data *rlc_data; uint16_t lost = 0, received = 0, skipped = 0; char info[RLC_MAX_WS + 1]; memset(info, '.', m_window.ws()); info[m_window.ws()] = 0; uint16_t bsn = 0; unsigned received_bytes = 0, lost_bytes = 0; unsigned received_packets = 0, lost_packets = 0; unsigned num_blocks = strlen(show_rbb); /* SSN - 1 is in range V(A)..V(S)-1 */ for (unsigned int bitpos = 0; bitpos < num_blocks; bitpos++) { bool is_received; int index = num_blocks - 1 - bitpos; is_received = (index >= 0 && show_rbb[index] == 'R'); bsn = m_window.mod_sns(bitnum_to_bsn(bitpos, ssn)); if (bsn == m_window.mod_sns(m_window.v_a() - 1)) { info[bitpos] = '$'; break; } rlc_data = m_rlc.block(bsn); if (!rlc_data) { info[bitpos] = '0'; continue; } /* Get general statistics */ if (is_received && !m_window.m_v_b.is_acked(bsn)) { received_packets += 1; received_bytes += rlc_data->len; } else if (!is_received && !m_window.m_v_b.is_nacked(bsn)) { lost_packets += 1; lost_bytes += rlc_data->len; } /* Get statistics for current CS */ if (rlc_data->cs_last != current_cs()) { /* This block has already been encoded with a different * CS, so it doesn't help us to decide, whether the * current CS is ok. Ignore it. */ info[bitpos] = 'x'; skipped += 1; continue; } if (is_received) { if (!m_window.m_v_b.is_acked(bsn)) { received += 1; info[bitpos] = 'R'; } else { info[bitpos] = 'r'; } } else { info[bitpos] = 'L'; lost += 1; } } LOGP(DRLCMACDL, LOGL_DEBUG, "%s DL analysis, range=%d:%d, lost=%d, recv=%d, " "skipped=%d, bsn=%d, info='%s'\n", name(), m_window.v_a(), m_window.v_s(), lost, received, skipped, bsn, info); res->received_packets = received_packets; res->lost_packets = lost_packets; res->received_bytes = received_bytes; res->lost_bytes = lost_bytes; if (lost + received <= 1) return -1; return lost * 100 / (lost + received); } int gprs_rlcmac_dl_tbf::update_window(unsigned first_bsn, const struct bitvec *rbb) { int16_t dist; /* must be signed */ uint16_t lost = 0, received = 0; char show_v_b[RLC_MAX_SNS + 1]; char show_rbb[RLC_MAX_SNS + 1]; int error_rate; struct ana_result ana_res; unsigned num_blocks = rbb->cur_bit; unsigned behind_last_bsn = m_window.mod_sns(first_bsn + num_blocks); Decoding::extract_rbb(rbb, show_rbb); /* show received array in debug */ LOGP(DRLCMACDL, LOGL_DEBUG, "- ack: (BSN=%d)\"%s\"" "(BSN=%d) R=ACK I=NACK\n", first_bsn, show_rbb, m_window.mod_sns(behind_last_bsn - 1)); /* apply received array to receive state (first_bsn..behind_last_bsn-1) */ if (num_blocks > 0) { /* calculate distance of ssn from V(S) */ dist = m_window.mod_sns(m_window.v_s() - behind_last_bsn); /* check if distance is less than distance V(A)..V(S) */ if (dist >= m_window.distance()) { /* this might happpen, if the downlink assignment * was not received by ms and the ack refers * to previous TBF * FIXME: we should implement polling for * control ack! * TODO: check whether this FIXME still makes sense */ LOGP(DRLCMACDL, LOGL_NOTICE, "- ack range is out of " "V(A)..V(S) range %s Free TBF!\n", tbf_name(this)); return 1; /* indicate to free TBF */ } } error_rate = analyse_errors(show_rbb, behind_last_bsn, &ana_res); if (bts_data()->cs_adj_enabled && ms()) ms()->update_error_rate(this, error_rate); m_window.update(bts, rbb, first_bsn, &lost, &received); /* report lost and received packets */ gprs_rlcmac_received_lost(this, received, lost); /* Used to measure the leak rate */ gprs_bssgp_update_bytes_received(ana_res.received_bytes, ana_res.received_packets + ana_res.lost_packets); /* raise V(A), if possible */ m_window.raise(m_window.move_window()); /* show receive state array in debug (V(A)..V(S)-1) */ m_window.show_state(show_v_b); LOGP(DRLCMACDL, LOGL_DEBUG, "- V(B): (V(A)=%d)\"%s\"" "(V(S)-1=%d) A=Acked N=Nacked U=Unacked " "X=Resend-Unacked I=Invalid\n", m_window.v_a(), show_v_b, m_window.v_s_mod(-1)); return 0; } int gprs_rlcmac_dl_tbf::update_window(const uint8_t ssn, const uint8_t *rbb) { int16_t dist; /* must be signed */ uint16_t lost = 0, received = 0; char show_rbb[65]; char show_v_b[RLC_MAX_SNS + 1]; int error_rate; struct ana_result ana_res; Decoding::extract_rbb(rbb, show_rbb); /* show received array in debug (bit 64..1) */ LOGP(DRLCMACDL, LOGL_DEBUG, "- ack: (BSN=%d)\"%s\"" "(BSN=%d) R=ACK I=NACK\n", m_window.mod_sns(ssn - 64), show_rbb, m_window.mod_sns(ssn - 1)); /* apply received array to receive state (SSN-64..SSN-1) */ /* calculate distance of ssn from V(S) */ dist = m_window.mod_sns(m_window.v_s() - ssn); /* check if distance is less than distance V(A)..V(S) */ if (dist >= m_window.distance()) { /* this might happpen, if the downlink assignment * was not received by ms and the ack refers * to previous TBF * FIXME: we should implement polling for * control ack!*/ LOGP(DRLCMACDL, LOGL_NOTICE, "- ack range is out of " "V(A)..V(S) range %s Free TBF!\n", tbf_name(this)); return 1; /* indicate to free TBF */ } error_rate = analyse_errors(show_rbb, ssn, &ana_res); if (bts_data()->cs_adj_enabled && ms()) ms()->update_error_rate(this, error_rate); m_window.update(bts, show_rbb, ssn, &lost, &received); /* report lost and received packets */ gprs_rlcmac_received_lost(this, received, lost); /* Used to measure the leak rate */ gprs_bssgp_update_bytes_received(ana_res.received_bytes, ana_res.received_packets + ana_res.lost_packets); /* raise V(A), if possible */ m_window.raise(m_window.move_window()); /* show receive state array in debug (V(A)..V(S)-1) */ m_window.show_state(show_v_b); LOGP(DRLCMACDL, LOGL_DEBUG, "- V(B): (V(A)=%d)\"%s\"" "(V(S)-1=%d) A=Acked N=Nacked U=Unacked " "X=Resend-Unacked I=Invalid\n", m_window.v_a(), show_v_b, m_window.v_s_mod(-1)); if (state_is(GPRS_RLCMAC_FINISHED) && m_window.window_empty()) { LOGP(DRLCMACDL, LOGL_NOTICE, "Received acknowledge of " "all blocks, but without final ack " "inidcation (don't worry)\n"); } return 0; } int gprs_rlcmac_dl_tbf::maybe_start_new_window() { release(); /* check for LLC PDU in the LLC Queue */ if (llc_queue()->size() > 0) /* we have more data so we will re-use this tbf */ establish_dl_tbf_on_pacch(); return 0; } int gprs_rlcmac_dl_tbf::release() { uint16_t received; /* range V(A)..V(S)-1 */ received = m_window.count_unacked(); /* report all outstanding packets as received */ gprs_rlcmac_received_lost(this, received, 0); set_state(GPRS_RLCMAC_WAIT_RELEASE); /* start T3193 */ tbf_timer_start(this, 3193, bts_data()->t3193_msec / 1000, (bts_data()->t3193_msec % 1000) * 1000); /* reset rlc states */ m_tx_counter = 0; m_wait_confirm = 0; m_window.reset(); /* keep to flags */ state_flags &= GPRS_RLCMAC_FLAG_TO_MASK; state_flags &= ~(1 << GPRS_RLCMAC_FLAG_CCCH); return 0; } int gprs_rlcmac_dl_tbf::abort() { uint16_t lost; if (state_is(GPRS_RLCMAC_FLOW)) { /* range V(A)..V(S)-1 */ lost = m_window.count_unacked(); /* report all outstanding packets as lost */ gprs_rlcmac_received_lost(this, 0, lost); gprs_rlcmac_lost_rep(this); /* TODO: Reschedule all LLC frames starting with the one that is * (partly) encoded in chunk 1 of block V(A). (optional) */ } set_state(GPRS_RLCMAC_RELEASING); /* reset rlc states */ m_window.reset(); /* keep to flags */ state_flags &= GPRS_RLCMAC_FLAG_TO_MASK; state_flags &= ~(1 << GPRS_RLCMAC_FLAG_CCCH); return 0; } int gprs_rlcmac_dl_tbf::rcvd_dl_ack(uint8_t final_ack, unsigned first_bsn, struct bitvec *rbb) { int rc; LOGP(DRLCMACDL, LOGL_DEBUG, "%s downlink acknowledge\n", tbf_name(this)); rc = update_window(first_bsn, rbb); if (final_ack) { LOGP(DRLCMACDL, LOGL_DEBUG, "- Final ACK received.\n"); rc = maybe_start_new_window(); } else if (state_is(GPRS_RLCMAC_FINISHED) && m_window.window_empty()) { LOGP(DRLCMACDL, LOGL_NOTICE, "Received acknowledge of " "all blocks, but without final ack " "indication (don't worry)\n"); } return rc; } int gprs_rlcmac_dl_tbf::rcvd_dl_ack(uint8_t final_ack, uint8_t ssn, uint8_t *rbb) { LOGP(DRLCMACDL, LOGL_DEBUG, "%s downlink acknowledge\n", tbf_name(this)); if (!final_ack) return update_window(ssn, rbb); LOGP(DRLCMACDL, LOGL_DEBUG, "- Final ACK received.\n"); return maybe_start_new_window(); } bool gprs_rlcmac_dl_tbf::dl_window_stalled() const { return m_window.window_stalled(); } void gprs_rlcmac_dl_tbf::request_dl_ack() { m_dl_ack_requested = true; } bool gprs_rlcmac_dl_tbf::need_control_ts() const { if (poll_state != GPRS_RLCMAC_POLL_NONE) return false; return state_flags & (1 << GPRS_RLCMAC_FLAG_TO_DL_ACK) || m_tx_counter >= POLL_ACK_AFTER_FRAMES || m_dl_ack_requested; } bool gprs_rlcmac_dl_tbf::have_data() const { return m_llc.chunk_size() > 0 || (llc_queue() && llc_queue()->size() > 0); } int gprs_rlcmac_dl_tbf::frames_since_last_poll(unsigned fn) const { unsigned wrapped; if (m_last_dl_poll_fn < 0) return -1; wrapped = (fn + 2715648 - m_last_dl_poll_fn) % 2715648; if (wrapped < 2715648/2) return wrapped; else return wrapped - 2715648; } int gprs_rlcmac_dl_tbf::frames_since_last_drain(unsigned fn) const { unsigned wrapped; if (m_last_dl_drained_fn < 0) return -1; wrapped = (fn + 2715648 - m_last_dl_drained_fn) % 2715648; if (wrapped < 2715648/2) return wrapped; else return wrapped - 2715648; } bool gprs_rlcmac_dl_tbf::keep_open(unsigned fn) const { int keep_time_frames; if (bts_data()->dl_tbf_idle_msec <= 0) return false; keep_time_frames = msecs_to_frames(bts_data()->dl_tbf_idle_msec); return frames_since_last_drain(fn) <= keep_time_frames; } /* * This function returns the pointer to data which needs * to be copied. Also updates the status of the block related to * Split block handling in the RLC/MAC block. */ enum egprs_rlc_dl_reseg_bsn_state gprs_rlcmac_dl_tbf::egprs_dl_get_data(int bsn, uint8_t **block_data) { gprs_rlc_data *rlc_data = m_rlc.block(bsn); egprs_rlc_dl_reseg_bsn_state *block_status_dl = &rlc_data->spb_status.block_status_dl; GprsCodingScheme &cs_current_trans = m_rlc.block(bsn)->cs_current_trans; GprsCodingScheme &cs_init = m_rlc.block(bsn)->cs_init; *block_data = &rlc_data->block[0]; /* * Table 10.3a.0.1 of 44.060 * MCS6,9: second segment starts at 74/2 = 37 * MCS5,7: second segment starts at 56/2 = 28 * MCS8: second segment starts at 31 * MCS4: second segment starts at 44/2 = 22 */ if (cs_current_trans.headerTypeData() == GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_3) { if (*block_status_dl == EGPRS_RESEG_FIRST_SEG_SENT) { switch (GprsCodingScheme::Scheme(cs_init)) { case GprsCodingScheme::MCS6 : case GprsCodingScheme::MCS9 : *block_data = &rlc_data->block[37]; break; case GprsCodingScheme::MCS7 : case GprsCodingScheme::MCS5 : *block_data = &rlc_data->block[28]; break; case GprsCodingScheme::MCS8 : *block_data = &rlc_data->block[31]; break; case GprsCodingScheme::MCS4 : *block_data = &rlc_data->block[22]; break; default: LOGP(DRLCMACDL, LOGL_ERROR, "Software error: " "--%s hit invalid condition. headerType(%d) " " blockstatus(%d) cs(%s) PLEASE FIX!\n", name(), cs_current_trans.headerTypeData(), *block_status_dl, cs_init.name()); break; } return EGPRS_RESEG_SECOND_SEG_SENT; } else if ((cs_init.headerTypeData() == GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_1) || (cs_init.headerTypeData() == GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_2)) { return EGPRS_RESEG_FIRST_SEG_SENT; } else if ((GprsCodingScheme::Scheme(cs_init) == GprsCodingScheme::MCS4) && (GprsCodingScheme::Scheme(cs_current_trans) == GprsCodingScheme::MCS1)) { return EGPRS_RESEG_FIRST_SEG_SENT; } } return EGPRS_RESEG_DL_DEFAULT; } /* * This function returns the status of split block * for RLC/MAC block. */ unsigned int gprs_rlcmac_dl_tbf::get_egprs_dl_spb_status(const int bsn) { const gprs_rlc_data *rlc_data = m_rlc.block(bsn); return rlc_data->spb_status.block_status_dl; } /* * This function returns the spb value to be sent OTA * for RLC/MAC block. */ enum egprs_rlcmac_dl_spb gprs_rlcmac_dl_tbf::get_egprs_dl_spb(const int bsn) { struct gprs_rlc_data *rlc_data = m_rlc.block(bsn); egprs_rlc_dl_reseg_bsn_state block_status_dl = rlc_data->spb_status.block_status_dl; GprsCodingScheme &cs_current_trans = m_rlc.block(bsn)->cs_current_trans; GprsCodingScheme &cs_init = m_rlc.block(bsn)->cs_init; /* Table 10.4.8b.1 of 44.060 */ if (cs_current_trans.headerTypeData() == GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_3) { /* * if we are sending the second segment the spb should be 3 * other wise it should be 2 */ if (block_status_dl == EGPRS_RESEG_FIRST_SEG_SENT) { return EGPRS_RLCMAC_DL_SEC_SEG; } else if ((cs_init.headerTypeData() == GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_1) || (cs_init.headerTypeData() == GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_2)) { return EGPRS_RLCMAC_DL_FIRST_SEG; } else if ((GprsCodingScheme::Scheme(cs_init) == GprsCodingScheme::MCS4) && (GprsCodingScheme::Scheme(cs_current_trans) == GprsCodingScheme::MCS1)) { return EGPRS_RLCMAC_DL_FIRST_SEG; } } /* Non SPB cases 0 is reurned */ return EGPRS_RLCMAC_DL_NO_RETX; } void gprs_rlcmac_dl_tbf::egprs_calc_window_size() { struct gprs_rlcmac_bts *bts_data = bts->bts_data(); unsigned int num_pdch = pcu_bitcount(dl_slots()); unsigned int ws = bts_data->ws_base + num_pdch * bts_data->ws_pdch; ws = (ws / 32) * 32; ws = OSMO_MAX(64, ws); if (num_pdch == 1) ws = OSMO_MIN(192, ws); else ws = OSMO_MIN(128 * num_pdch, ws); LOGP(DRLCMAC, LOGL_INFO, "%s: Setting EGPRS window size to %d\n", name(), ws); m_window.set_ws(ws); }