| /* Data block transfer |
| * |
| * Copyright (C) 2012 Ivan Klyuchnikov |
| * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu> |
| * |
| * 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 <gprs_bssgp_pcu.h> |
| #include <gprs_rlcmac.h> |
| #include <pcu_l1_if.h> |
| #include <bts.h> |
| #include <encoding.h> |
| #include <tbf.h> |
| #include <rlc.h> |
| |
| static struct gprs_rlcmac_cs gprs_rlcmac_cs[] = { |
| /* frame length data block max payload */ |
| { 0, 0, 0 }, |
| { 23, 23, 20 }, /* CS-1 */ |
| { 34, 33, 30 }, /* CS-2 */ |
| { 40, 39, 36 }, /* CS-3 */ |
| { 54, 53, 50 }, /* CS-4 */ |
| }; |
| |
| |
| extern void *tall_pcu_ctx; |
| |
| /* After sending these frames, we poll for ack/nack. */ |
| #define POLL_ACK_AFTER_FRAMES 20 |
| |
| /* If acknowledgement to uplink/downlink assignmentshould be polled */ |
| #define POLLING_ASSIGNMENT_DL 1 |
| #define POLLING_ASSIGNMENT_UL 1 |
| |
| |
| #ifdef DEBUG_DL_ASS_IDLE |
| char debug_imsi[16]; |
| #endif |
| |
| /* |
| * UL data block flow |
| */ |
| |
| struct msgb *gprs_rlcmac_send_uplink_ack( |
| struct gprs_rlcmac_tbf *tbf, |
| uint32_t fn) |
| { |
| int final = (tbf->state_is(GPRS_RLCMAC_FINISHED)); |
| gprs_rlcmac_bts *bts = tbf->bts->bts_data(); |
| struct msgb *msg; |
| |
| if (final) { |
| if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) { |
| LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already " |
| "sheduled for TBF=%d, so we must wait for " |
| "final uplink ack...\n", tbf->tfi); |
| return NULL; |
| } |
| if (tbf->bts->sba()->find(tbf->trx_no, tbf->control_ts, (fn + 13) % 2715648)) { |
| LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already " |
| "scheduled for single block allocation...\n"); |
| return NULL; |
| } |
| } |
| |
| msg = msgb_alloc(23, "rlcmac_ul_ack"); |
| if (!msg) |
| return NULL; |
| bitvec *ack_vec = bitvec_alloc(23); |
| if (!ack_vec) { |
| msgb_free(msg); |
| return NULL; |
| } |
| bitvec_unhex(ack_vec, |
| "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| RlcMacDownlink_t * mac_control_block = (RlcMacDownlink_t *)talloc_zero(tall_pcu_ctx, RlcMacDownlink_t); |
| Encoding::write_packet_uplink_ack(bts, mac_control_block, tbf, final); |
| encode_gsm_rlcmac_downlink(ack_vec, mac_control_block); |
| bitvec_pack(ack_vec, msgb_put(msg, 23)); |
| bitvec_free(ack_vec); |
| talloc_free(mac_control_block); |
| |
| /* now we must set this flag, so we are allowed to assign downlink |
| * TBF on PACCH. it is only allowed when TLLI is aknowledged. */ |
| tbf->dir.ul.contention_resolution_done = 1; |
| |
| if (final) { |
| tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; |
| tbf->poll_fn = (fn + 13) % 2715648; |
| /* waiting for final acknowledge */ |
| tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_WAIT_ACK; |
| tbf->dir.ul.final_ack_sent = 1; |
| } else |
| tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_NONE; |
| debug_diagram(bts->bts, tbf->diag, "send UL-ACK"); |
| |
| return msg; |
| } |
| |
| struct msgb *gprs_rlcmac_send_packet_uplink_assignment( |
| struct gprs_rlcmac_tbf *tbf, uint32_t fn) |
| { |
| struct msgb *msg; |
| struct gprs_rlcmac_tbf *new_tbf; |
| gprs_rlcmac_bts *bts = tbf->bts->bts_data(); |
| |
| #if POLLING_ASSIGNMENT_UL == 1 |
| if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) { |
| LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already " |
| "sheduled for TBF=%d, so we must wait for uplink " |
| "assignment...\n", tbf->tfi); |
| return NULL; |
| } |
| if (tbf->bts->sba()->find(tbf->trx_no, tbf->control_ts, (fn + 13) % 2715648)) { |
| LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already scheduled for " |
| "single block allocation...\n"); |
| return NULL; |
| } |
| #endif |
| |
| /* on down TBF we get the uplink TBF to be assigned. */ |
| if (tbf->direction == GPRS_RLCMAC_DL_TBF) |
| new_tbf = tbf->bts->tbf_by_tlli(tbf->tlli, GPRS_RLCMAC_UL_TBF); |
| else |
| new_tbf = tbf; |
| |
| if (!new_tbf) { |
| LOGP(DRLCMACUL, LOGL_ERROR, "We have a schedule for uplink " |
| "assignment at downlink TBF=%d, but there is no uplink " |
| "TBF\n", tbf->tfi); |
| tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_NONE; |
| return NULL; |
| } |
| |
| msg = msgb_alloc(23, "rlcmac_ul_ass"); |
| if (!msg) |
| return NULL; |
| LOGP(DRLCMAC, LOGL_INFO, "TBF: START TFI: %u TLLI: 0x%08x Packet Uplink Assignment (PACCH)\n", new_tbf->tfi, new_tbf->tlli); |
| bitvec *ass_vec = bitvec_alloc(23); |
| if (!ass_vec) { |
| msgb_free(msg); |
| return NULL; |
| } |
| bitvec_unhex(ass_vec, |
| "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| Encoding::write_packet_uplink_assignment(bts, ass_vec, tbf->tfi, |
| (tbf->direction == GPRS_RLCMAC_DL_TBF), tbf->tlli, |
| tbf->tlli_valid, new_tbf, POLLING_ASSIGNMENT_UL, bts->alpha, |
| bts->gamma, -1); |
| bitvec_pack(ass_vec, msgb_put(msg, 23)); |
| RlcMacDownlink_t * mac_control_block = (RlcMacDownlink_t *)talloc_zero(tall_pcu_ctx, RlcMacDownlink_t); |
| LOGP(DRLCMAC, LOGL_DEBUG, "+++++++++++++++++++++++++ TX : Packet Uplink Assignment +++++++++++++++++++++++++\n"); |
| decode_gsm_rlcmac_downlink(ass_vec, mac_control_block); |
| LOGPC(DCSN1, LOGL_NOTICE, "\n"); |
| LOGP(DRLCMAC, LOGL_DEBUG, "------------------------- TX : Packet Uplink Assignment -------------------------\n"); |
| bitvec_free(ass_vec); |
| talloc_free(mac_control_block); |
| |
| #if POLLING_ASSIGNMENT_UL == 1 |
| tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; |
| tbf->poll_fn = (fn + 13) % 2715648; |
| tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_WAIT_ACK; |
| #else |
| tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_NONE; |
| tbf_new_state(new_tbf, GPRS_RLCMAC_FLOW); |
| tbf_assign_control_ts(new_tbf); |
| #endif |
| debug_diagram(bts->bts, tbf->diag, "send UL-ASS"); |
| |
| return msg; |
| } |
| |
| int gprs_rlcmac_rcv_rach(struct gprs_rlcmac_bts *bts, |
| uint8_t ra, uint32_t Fn, int16_t qta) |
| { |
| struct gprs_rlcmac_tbf *tbf; |
| uint8_t trx, ts = 0; |
| int8_t tfi; /* must be signed */ |
| uint8_t sb = 0; |
| uint32_t sb_fn = 0; |
| int rc; |
| uint8_t plen; |
| |
| LOGP(DRLCMAC, LOGL_DEBUG, "MS requests UL TBF on RACH, so we provide " |
| "one:\n"); |
| if ((ra & 0xf8) == 0x70) { |
| LOGP(DRLCMAC, LOGL_DEBUG, "MS requests single block " |
| "allocation\n"); |
| sb = 1; |
| } else if (bts->force_two_phase) { |
| LOGP(DRLCMAC, LOGL_DEBUG, "MS requests single phase access, " |
| "but we force two phase access\n"); |
| sb = 1; |
| } |
| if (qta < 0) |
| qta = 0; |
| if (qta > 252) |
| qta = 252; |
| if (sb) { |
| rc = bts->bts->sba()->alloc(&trx, &ts, &sb_fn, qta >> 2); |
| if (rc < 0) |
| return rc; |
| LOGP(DRLCMAC, LOGL_DEBUG, "RX: [PCU <- BTS] RACH qbit-ta=%d " |
| "ra=0x%02x, Fn=%d (%d,%d,%d)\n", qta, ra, Fn, |
| (Fn / (26 * 51)) % 32, Fn % 51, Fn % 26); |
| LOGP(DRLCMAC, LOGL_INFO, "TX: Immediate Assignment Uplink " |
| "(AGCH)\n"); |
| } else { |
| // Create new TBF |
| #warning "Copy and pate with other routines.." |
| tfi = bts->bts->tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx, -1); |
| if (tfi < 0) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH ressource\n"); |
| /* FIXME: send reject */ |
| return -EBUSY; |
| } |
| /* set class to 0, since we don't know the multislot class yet */ |
| tbf = tbf_alloc(bts, NULL, GPRS_RLCMAC_UL_TBF, tfi, trx, 0, 1); |
| if (!tbf) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH ressource\n"); |
| /* FIXME: send reject */ |
| return -EBUSY; |
| } |
| tbf->ta = qta >> 2; |
| tbf_new_state(tbf, GPRS_RLCMAC_FLOW); |
| tbf->state_flags |= (1 << GPRS_RLCMAC_FLAG_CCCH); |
| tbf_timer_start(tbf, 3169, bts->t3169, 0); |
| LOGP(DRLCMAC, LOGL_DEBUG, "TBF: [UPLINK] START TFI: %u\n", |
| tbf->tfi); |
| LOGP(DRLCMAC, LOGL_DEBUG, "RX: [PCU <- BTS] TFI: %u RACH " |
| "qbit-ta=%d ra=0x%02x, Fn=%d (%d,%d,%d)\n", tbf->tfi, |
| qta, ra, Fn, (Fn / (26 * 51)) % 32, Fn % 51, Fn % 26); |
| LOGP(DRLCMAC, LOGL_INFO, "TX: START TFI: %u Immediate " |
| "Assignment Uplink (AGCH)\n", tbf->tfi); |
| } |
| bitvec *immediate_assignment = bitvec_alloc(22) /* without plen */; |
| bitvec_unhex(immediate_assignment, |
| "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| if (sb) |
| plen = Encoding::write_immediate_assignment(bts, immediate_assignment, 0, ra, |
| Fn, qta >> 2, bts->trx[trx].arfcn, ts, |
| bts->trx[trx].pdch[ts].tsc, 0, 0, 0, 0, sb_fn, 1, |
| bts->alpha, bts->gamma, -1); |
| else |
| plen = Encoding::write_immediate_assignment(bts, immediate_assignment, 0, ra, |
| Fn, tbf->ta, tbf->arfcn, tbf->first_ts, tbf->tsc, |
| tbf->tfi, tbf->dir.ul.usf[tbf->first_ts], 0, 0, 0, 0, |
| bts->alpha, bts->gamma, -1); |
| pcu_l1if_tx_agch(immediate_assignment, plen); |
| bitvec_free(immediate_assignment); |
| |
| return 0; |
| } |
| |
| |
| /* send DL data block |
| * |
| * The messages are fragmented and forwarded as data blocks. |
| */ |
| struct msgb *gprs_rlcmac_send_data_block_acknowledged( |
| struct gprs_rlcmac_tbf *tbf, uint32_t fn, uint8_t ts) |
| { |
| struct rlc_dl_header *rh; |
| struct rlc_li_field *li; |
| uint8_t block_length; /* total length of block, including spare bits */ |
| uint8_t block_data; /* usable data of block, w/o spare bits, inc. MAC */ |
| struct msgb *msg, *dl_msg; |
| uint8_t bsn; |
| uint16_t mod_sns = tbf->sns - 1; |
| uint16_t mod_sns_half = (tbf->sns >> 1) - 1; |
| uint16_t index; |
| uint8_t *delimiter, *data, *e_pointer; |
| uint8_t len; |
| uint16_t space, chunk; |
| int first_fin_ack = 0; |
| gprs_rlcmac_bts *bts = tbf->bts->bts_data(); |
| |
| LOGP(DRLCMACDL, LOGL_DEBUG, "DL DATA TBF=%d downlink (V(A)==%d .. " |
| "V(S)==%d)\n", tbf->tfi, tbf->dir.dl.v_a, tbf->dir.dl.v_s); |
| |
| do_resend: |
| /* check if there is a block with negative acknowledgement */ |
| for (bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; |
| bsn = (bsn + 1) & mod_sns) { |
| index = (bsn & mod_sns_half); |
| if (tbf->dir.dl.v_b[index] == 'N' |
| || tbf->dir.dl.v_b[index] == 'X') { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- Resending BSN %d\n", |
| bsn); |
| /* re-send block with negative aknowlegement */ |
| tbf->dir.dl.v_b[index] = 'U'; /* unacked */ |
| goto tx_block; |
| } |
| } |
| |
| /* if the window has stalled, or transfer is complete, |
| * send an unacknowledged block */ |
| if (tbf->state_is(GPRS_RLCMAC_FINISHED) |
| || ((tbf->dir.dl.v_s - tbf->dir.dl.v_a) & mod_sns) == tbf->ws) { |
| int resend = 0; |
| |
| if (tbf->state_is(GPRS_RLCMAC_FINISHED)) |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " |
| "because all blocks have been transmitted.\n", |
| tbf->dir.dl.v_a); |
| else |
| LOGP(DRLCMACDL, LOGL_NOTICE, "- Restarting at BSN %d, " |
| "because all window is stalled.\n", |
| tbf->dir.dl.v_a); |
| /* 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 (tbf->dir.dl.v_s == tbf->dir.dl.v_a) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- MS acked all blocks, " |
| "so we re-transmit final block!\n"); |
| /* we just send final block again */ |
| index = ((tbf->dir.dl.v_s - 1) & mod_sns_half); |
| goto tx_block; |
| } |
| |
| /* cycle through all unacked blocks */ |
| for (bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; |
| bsn = (bsn + 1) & mod_sns) { |
| index = (bsn & mod_sns_half); |
| if (tbf->dir.dl.v_b[index] == 'U') { |
| /* mark to be re-send */ |
| tbf->dir.dl.v_b[index] = 'X'; |
| resend++; |
| } |
| } |
| /* At this point there should be at leasst 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"); |
| /* we just send final block again */ |
| index = ((tbf->dir.dl.v_s - 1) & mod_sns_half); |
| goto tx_block; |
| } |
| goto do_resend; |
| } |
| |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- Sending new block at BSN %d\n", |
| tbf->dir.dl.v_s); |
| |
| /* now we still have untransmitted LLC data, so we fill mac block */ |
| index = tbf->dir.dl.v_s & mod_sns_half; |
| data = tbf->rlc_block[index]; |
| #warning "Selection of the CS doesn't belong here" |
| if (tbf->cs == 0) { |
| tbf->cs = bts->initial_cs_dl; |
| if (tbf->cs < 1 || tbf->cs > 4) |
| tbf->cs = 1; |
| } |
| block_length = gprs_rlcmac_cs[tbf->cs].block_length; |
| block_data = gprs_rlcmac_cs[tbf->cs].block_data; |
| memset(data, 0x2b, block_data); /* spare bits will be left 0 */ |
| rh = (struct rlc_dl_header *)data; |
| rh->pt = 0; /* Data Block */ |
| rh->rrbp = rh->s_p = 0; /* Polling, set later, if required */ |
| rh->usf = 7; /* will be set at scheduler */ |
| rh->pr = 0; /* FIXME: power reduction */ |
| rh->tfi = tbf->tfi; /* TFI */ |
| rh->fbi = 0; /* Final Block Indicator, set late, if true */ |
| rh->bsn = tbf->dir.dl.v_s; /* Block Sequence Number */ |
| rh->e = 0; /* Extension bit, maybe set later */ |
| e_pointer = data + 2; /* points to E of current chunk */ |
| data += 3; |
| delimiter = data; /* where next length header would be stored */ |
| space = block_data - 3; |
| while (1) { |
| chunk = tbf->llc_length - tbf->llc_index; |
| /* if chunk will exceed block limit */ |
| if (chunk > space) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " |
| "larger than space (%d) left in block: copy " |
| "only remaining space, and we are done\n", |
| chunk, space); |
| /* block is filled, so there is no extension */ |
| *e_pointer |= 0x01; |
| /* fill only space */ |
| memcpy(data, tbf->llc_frame + tbf->llc_index, space); |
| /* incement index */ |
| tbf->llc_index += space; |
| /* return data block as message */ |
| break; |
| } |
| /* if FINAL chunk would fit precisely in space left */ |
| if (chunk == space && llist_empty(&tbf->llc_queue)) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " |
| "would exactly fit into space (%d): because " |
| "this is a final block, we don't add length " |
| "header, and we are done\n", chunk, space); |
| LOGP(DRLCMACDL, LOGL_INFO, "Complete DL frame for " |
| "TBF=%d that fits precisely in last block: " |
| "len=%d\n", tbf->tfi, tbf->llc_length); |
| gprs_rlcmac_dl_bw(tbf, tbf->llc_length); |
| /* block is filled, so there is no extension */ |
| *e_pointer |= 0x01; |
| /* fill space */ |
| memcpy(data, tbf->llc_frame + tbf->llc_index, space); |
| /* reset LLC frame */ |
| tbf->llc_index = tbf->llc_length = 0; |
| /* final block */ |
| rh->fbi = 1; /* we indicate final block */ |
| tbf_new_state(tbf, GPRS_RLCMAC_FINISHED); |
| /* return data block as message */ |
| break; |
| } |
| /* if chunk would fit exactly in space left */ |
| if (chunk == space) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " |
| "would exactly fit into space (%d): add length " |
| "header with LI=0, to make frame extend to " |
| "next block, and we are done\n", chunk, space); |
| /* make space for delimiter */ |
| if (delimiter != data) |
| memcpy(delimiter + 1, delimiter, |
| data - delimiter); |
| data++; |
| space--; |
| /* add LI with 0 length */ |
| li = (struct rlc_li_field *)delimiter; |
| li->e = 1; /* not more extension */ |
| li->m = 0; /* shall be set to 0, in case of li = 0 */ |
| li->li = 0; /* chunk fills the complete space */ |
| // no need to set e_pointer nor increase delimiter |
| /* fill only space, which is 1 octet less than chunk */ |
| memcpy(data, tbf->llc_frame + tbf->llc_index, space); |
| /* incement index */ |
| tbf->llc_index += space; |
| /* return data block as message */ |
| break; |
| } |
| LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d is less " |
| "than remaining space (%d): add length header to " |
| "to delimit LLC frame\n", chunk, space); |
| /* the LLC frame chunk ends in this block */ |
| /* make space for delimiter */ |
| if (delimiter != data) |
| memcpy(delimiter + 1, delimiter, data - delimiter); |
| data++; |
| space--; |
| /* add LI to delimit frame */ |
| li = (struct rlc_li_field *)delimiter; |
| li->e = 0; /* Extension bit, maybe set later */ |
| li->m = 0; /* will be set later, if there is more LLC data */ |
| li->li = chunk; /* length of chunk */ |
| e_pointer = delimiter; /* points to E of current delimiter */ |
| delimiter++; |
| /* copy (rest of) LLC frame to space */ |
| memcpy(data, tbf->llc_frame + tbf->llc_index, chunk); |
| data += chunk; |
| space -= chunk; |
| LOGP(DRLCMACDL, LOGL_INFO, "Complete DL frame for TBF=%d: " |
| "len=%d\n", tbf->tfi, tbf->llc_length); |
| gprs_rlcmac_dl_bw(tbf, tbf->llc_length); |
| /* reset LLC frame */ |
| tbf->llc_index = tbf->llc_length = 0; |
| /* dequeue next LLC frame, if any */ |
| msg = tbf->llc_dequeue(gprs_bssgp_pcu_current_bctx()); |
| if (msg) { |
| LOGP(DRLCMACDL, LOGL_INFO, "- Dequeue next LLC for " |
| "TBF=%d (len=%d)\n", tbf->tfi, msg->len); |
| tbf->update_llc_frame(msg); |
| msgb_free(msg); |
| } |
| /* if we have more data and we have space left */ |
| if (space > 0 && tbf->llc_length) { |
| li->m = 1; /* we indicate more frames to follow */ |
| continue; |
| } |
| /* if we don't have more LLC frames */ |
| if (!tbf->llc_length) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "-- Final block, so we " |
| "done.\n"); |
| li->e = 1; /* we cannot extend */ |
| rh->fbi = 1; /* we indicate final block */ |
| first_fin_ack = 1; |
| /* + 1 indicates: first final ack */ |
| tbf_new_state(tbf, GPRS_RLCMAC_FINISHED); |
| break; |
| } |
| /* we have no space left */ |
| LOGP(DRLCMACDL, LOGL_DEBUG, "-- No space left, so we are " |
| "done.\n"); |
| li->e = 1; /* we cannot extend */ |
| break; |
| } |
| LOGP(DRLCMACDL, LOGL_DEBUG, "data block: %s\n", |
| osmo_hexdump(tbf->rlc_block[index], block_length)); |
| tbf->rlc_block_len[index] = block_length; |
| /* raise send state and set ack state array */ |
| tbf->dir.dl.v_b[index] = 'U'; /* unacked */ |
| tbf->dir.dl.v_s = (tbf->dir.dl.v_s + 1) & mod_sns; /* inc send state */ |
| |
| tx_block: |
| /* from this point on, new block is sent or old block is resent */ |
| |
| /* get data and header from current block */ |
| data = tbf->rlc_block[index]; |
| len = tbf->rlc_block_len[index]; |
| rh = (struct rlc_dl_header *)data; |
| |
| /* Clear Polling, if still set in history buffer */ |
| rh->s_p = 0; |
| |
| /* poll after POLL_ACK_AFTER_FRAMES frames, or when final block is tx. |
| */ |
| if (tbf->dir.dl.tx_counter >= POLL_ACK_AFTER_FRAMES || first_fin_ack) { |
| if (first_fin_ack) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " |
| "polling, because first final block sent.\n"); |
| } else { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " |
| "polling, because %d blocks sent.\n", |
| POLL_ACK_AFTER_FRAMES); |
| } |
| /* scheduling not possible, because: */ |
| if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) |
| LOGP(DRLCMAC, LOGL_DEBUG, "Polling is already " |
| "sheduled for TBF=%d, so we must wait for " |
| "requesting downlink ack\n", tbf->tfi); |
| else if (tbf->control_ts != ts) |
| LOGP(DRLCMAC, LOGL_DEBUG, "Polling cannot be " |
| "sheduled in this TS %d, waiting for " |
| "TS %d\n", ts, tbf->control_ts); |
| else if (tbf->bts->sba()->find(tbf->trx_no, ts, (fn + 13) % 2715648)) |
| LOGP(DRLCMAC, LOGL_DEBUG, "Polling cannot be " |
| "sheduled, because single block alllocation " |
| "already exists\n"); |
| else { |
| LOGP(DRLCMAC, LOGL_DEBUG, "Polling sheduled in this " |
| "TS %d\n", ts); |
| tbf->dir.dl.tx_counter = 0; |
| /* start timer whenever we send the final block */ |
| if (rh->fbi == 1) |
| tbf_timer_start(tbf, 3191, bts->t3191, 0); |
| |
| /* schedule polling */ |
| tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; |
| tbf->poll_fn = (fn + 13) % 2715648; |
| |
| #ifdef DEBUG_DIAGRAM |
| debug_diagram(bts->bts, tbf->diag, "poll DL-ACK"); |
| if (first_fin_ack) |
| debug_diagram(bts->bts, tbf->diag, "(is first FINAL)"); |
| if (rh->fbi) |
| debug_diagram(bts->bts, tbf->diag, "(FBI is set)"); |
| #endif |
| |
| /* set polling in header */ |
| rh->rrbp = 0; /* N+13 */ |
| rh->s_p = 1; /* Polling */ |
| |
| /* Increment TX-counter */ |
| tbf->dir.dl.tx_counter++; |
| } |
| } else { |
| /* Increment TX-counter */ |
| tbf->dir.dl.tx_counter++; |
| } |
| |
| /* return data block as message */ |
| dl_msg = msgb_alloc(len, "rlcmac_dl_data"); |
| if (!dl_msg) |
| return NULL; |
| memcpy(msgb_put(dl_msg, len), data, len); |
| |
| return dl_msg; |
| } |
| |
| int gprs_rlcmac_downlink_ack( |
| struct gprs_rlcmac_tbf *tbf, uint8_t final, |
| uint8_t ssn, uint8_t *rbb) |
| { |
| char show_rbb[65], show_v_b[RLC_MAX_SNS + 1]; |
| uint16_t mod_sns = tbf->sns - 1; |
| uint16_t mod_sns_half = (tbf->sns >> 1) - 1; |
| int i; /* must be signed */ |
| int16_t dist; /* must be signed */ |
| uint8_t bit; |
| uint16_t bsn; |
| struct msgb *msg; |
| uint16_t lost = 0, received = 0; |
| |
| LOGP(DRLCMACDL, LOGL_DEBUG, "TBF=%d downlink acknowledge\n", |
| tbf->tfi); |
| |
| if (!final) { |
| /* show received array in debug (bit 64..1) */ |
| for (i = 63; i >= 0; i--) { |
| bit = (rbb[i >> 3] >> (7 - (i&7))) & 1; |
| show_rbb[i] = (bit) ? '1' : 'o'; |
| } |
| show_rbb[64] = '\0'; |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- ack: (BSN=%d)\"%s\"" |
| "(BSN=%d) 1=ACK o=NACK\n", (ssn - 64) & mod_sns, |
| show_rbb, (ssn - 1) & mod_sns); |
| |
| /* apply received array to receive state (SSN-64..SSN-1) */ |
| /* calculate distance of ssn from V(S) */ |
| dist = (tbf->dir.dl.v_s - ssn) & mod_sns; |
| /* check if distance is less than distance V(A)..V(S) */ |
| if (dist >= ((tbf->dir.dl.v_s - tbf->dir.dl.v_a) & mod_sns)) { |
| /* 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 (DL TBF=%d) Free TFB!\n", |
| tbf->tfi); |
| return 1; /* indicate to free TBF */ |
| } |
| /* SSN - 1 is in range V(A)..V(S)-1 */ |
| for (i = 63, bsn = (ssn - 1) & mod_sns; |
| i >= 0 && bsn != ((tbf->dir.dl.v_a - 1) & mod_sns); |
| i--, bsn = (bsn - 1) & mod_sns) { |
| bit = (rbb[i >> 3] >> (7 - (i&7))) & 1; |
| if (bit) { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- got " |
| "ack for BSN=%d\n", bsn); |
| if (tbf->dir.dl.v_b[bsn & mod_sns_half] |
| != 'A') |
| received++; |
| tbf->dir.dl.v_b[bsn & mod_sns_half] = 'A'; |
| } else { |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- got " |
| "NACK for BSN=%d\n", bsn); |
| tbf->dir.dl.v_b[bsn & mod_sns_half] = 'N'; |
| lost++; |
| } |
| } |
| /* report lost and received packets */ |
| gprs_rlcmac_received_lost(tbf, received, lost); |
| |
| /* raise V(A), if possible */ |
| for (i = 0, bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; |
| i++, bsn = (bsn + 1) & mod_sns) { |
| if (tbf->dir.dl.v_b[bsn & mod_sns_half] == 'A') { |
| tbf->dir.dl.v_b[bsn & mod_sns_half] = 'I'; |
| /* mark invalid */ |
| tbf->dir.dl.v_a = (tbf->dir.dl.v_a + 1) |
| & mod_sns; |
| } else |
| break; |
| } |
| |
| /* show receive state array in debug (V(A)..V(S)-1) */ |
| for (i = 0, bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; |
| i++, bsn = (bsn + 1) & mod_sns) { |
| show_v_b[i] = tbf->dir.dl.v_b[bsn & mod_sns_half]; |
| if (show_v_b[i] == 0) |
| show_v_b[i] = ' '; |
| } |
| show_v_b[i] = '\0'; |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- V(B): (V(A)=%d)\"%s\"" |
| "(V(S)-1=%d) A=Acked N=Nacked U=Unacked " |
| "X=Resend-Unacked\n", tbf->dir.dl.v_a, show_v_b, |
| (tbf->dir.dl.v_s - 1) & mod_sns); |
| |
| if (tbf->state_is(GPRS_RLCMAC_FINISHED) |
| && tbf->dir.dl.v_s == tbf->dir.dl.v_a) { |
| LOGP(DRLCMACDL, LOGL_NOTICE, "Received acknowledge of " |
| "all blocks, but without final ack " |
| "inidcation (don't worry)\n"); |
| } |
| return 0; |
| } |
| |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- Final ACK received.\n"); |
| debug_diagram(tbf->bts, tbf->diag, "got Final ACK"); |
| /* range V(A)..V(S)-1 */ |
| for (bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; |
| bsn = (bsn + 1) & mod_sns) { |
| if (tbf->dir.dl.v_b[bsn & mod_sns_half] != 'A') |
| received++; |
| } |
| |
| /* report all outstanding packets as received */ |
| gprs_rlcmac_received_lost(tbf, received, lost); |
| |
| /* check for LLC PDU in the LLC Queue */ |
| msg = tbf->llc_dequeue(gprs_bssgp_pcu_current_bctx()); |
| if (!msg) { |
| /* no message, start T3193, change state to RELEASE */ |
| LOGP(DRLCMACDL, LOGL_DEBUG, "- No new message, so we " |
| "release.\n"); |
| /* start T3193 */ |
| debug_diagram(bts->bts, tbf->diag, "start T3193"); |
| tbf_timer_start(tbf, 3193, |
| tbf->bts->bts_data()->t3193_msec / 1000, |
| (tbf->bts->bts_data()->t3193_msec % 1000) * 1000); |
| tbf_new_state(tbf, GPRS_RLCMAC_WAIT_RELEASE); |
| |
| return 0; |
| } |
| #warning "Copy and paste on the sender path" |
| tbf->update_llc_frame(msg); |
| msgb_free(msg); |
| |
| /* we have a message, so we trigger downlink assignment, and there |
| * set the state to ASSIGN. also we set old_downlink, because we |
| * re-use this tbf. */ |
| LOGP(DRLCMAC, LOGL_DEBUG, "Trigger dowlink assignment on PACCH, " |
| "because another LLC PDU has arrived in between\n"); |
| memset(&tbf->dir.dl, 0, sizeof(tbf->dir.dl)); /* reset RLC states */ |
| tbf->state_flags &= GPRS_RLCMAC_FLAG_TO_MASK; /* keep TO flags */ |
| tbf->state_flags &= ~(1 << GPRS_RLCMAC_FLAG_CCCH); |
| tbf->update(); |
| gprs_rlcmac_trigger_downlink_assignment(tbf, tbf, NULL); |
| |
| return 0; |
| } |
| |
| |
| struct msgb *gprs_rlcmac_send_packet_downlink_assignment( |
| struct gprs_rlcmac_tbf *tbf, uint32_t fn) |
| { |
| struct msgb *msg; |
| struct gprs_rlcmac_tbf *new_tbf; |
| gprs_rlcmac_bts *bts = tbf->bts->bts_data(); |
| int poll_ass_dl = POLLING_ASSIGNMENT_DL; |
| |
| if (poll_ass_dl && tbf->direction == GPRS_RLCMAC_DL_TBF |
| && tbf->control_ts != tbf->first_common_ts) { |
| LOGP(DRLCMAC, LOGL_NOTICE, "Cannot poll for downlink " |
| "assigment, because MS cannot reply. (control TS=%d, " |
| "first common TS=%d)\n", tbf->control_ts, |
| tbf->first_common_ts); |
| poll_ass_dl = 0; |
| } |
| if (poll_ass_dl) { |
| if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) { |
| LOGP(DRLCMAC, LOGL_DEBUG, "Polling is already sheduled " |
| "for TBF=%d, so we must wait for downlink " |
| "assignment...\n", tbf->tfi); |
| return NULL; |
| } |
| if (tbf->bts->sba()->find(tbf->trx_no, tbf->control_ts, (fn + 13) % 2715648)) { |
| LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already " |
| "scheduled for single block allocation...\n"); |
| return NULL; |
| } |
| } |
| |
| /* on uplink TBF we get the downlink TBF to be assigned. */ |
| if (tbf->direction == GPRS_RLCMAC_UL_TBF) { |
| /* be sure to check first, if contention resolution is done, |
| * otherwise we cannot send the assignment yet */ |
| if (!tbf->dir.ul.contention_resolution_done) { |
| LOGP(DRLCMAC, LOGL_DEBUG, "Cannot assign DL TBF now, " |
| "because contention resolution is not " |
| "finished.\n"); |
| return NULL; |
| } |
| new_tbf = tbf->bts->tbf_by_tlli(tbf->tlli, GPRS_RLCMAC_DL_TBF); |
| } else |
| new_tbf = tbf; |
| if (!new_tbf) { |
| LOGP(DRLCMACDL, LOGL_ERROR, "We have a schedule for downlink " |
| "assignment at uplink TBF=%d, but there is no downlink " |
| "TBF\n", tbf->tfi); |
| tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_NONE; |
| return NULL; |
| } |
| |
| msg = msgb_alloc(23, "rlcmac_dl_ass"); |
| if (!msg) |
| return NULL; |
| bitvec *ass_vec = bitvec_alloc(23); |
| if (!ass_vec) { |
| msgb_free(msg); |
| return NULL; |
| } |
| bitvec_unhex(ass_vec, |
| "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); |
| LOGP(DRLCMAC, LOGL_INFO, "TBF: START TFI: %u TLLI: 0x%08x Packet Downlink Assignment (PACCH)\n", new_tbf->tfi, new_tbf->tlli); |
| RlcMacDownlink_t * mac_control_block = (RlcMacDownlink_t *)talloc_zero(tall_pcu_ctx, RlcMacDownlink_t); |
| Encoding::write_packet_downlink_assignment(mac_control_block, tbf->tfi, |
| (tbf->direction == GPRS_RLCMAC_DL_TBF), new_tbf, |
| poll_ass_dl, bts->alpha, bts->gamma, -1, 0); |
| LOGP(DRLCMAC, LOGL_DEBUG, "+++++++++++++++++++++++++ TX : Packet Downlink Assignment +++++++++++++++++++++++++\n"); |
| encode_gsm_rlcmac_downlink(ass_vec, mac_control_block); |
| LOGPC(DCSN1, LOGL_NOTICE, "\n"); |
| LOGP(DRLCMAC, LOGL_DEBUG, "------------------------- TX : Packet Downlink Assignment -------------------------\n"); |
| bitvec_pack(ass_vec, msgb_put(msg, 23)); |
| bitvec_free(ass_vec); |
| talloc_free(mac_control_block); |
| |
| if (poll_ass_dl) { |
| tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; |
| tbf->poll_fn = (fn + 13) % 2715648; |
| tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_WAIT_ACK; |
| } else { |
| tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_NONE; |
| tbf_new_state(new_tbf, GPRS_RLCMAC_FLOW); |
| tbf_assign_control_ts(new_tbf); |
| /* stop pending assignment timer */ |
| new_tbf->stop_timer(); |
| |
| } |
| debug_diagram(bts->bts, tbf->diag, "send DL-ASS"); |
| |
| return msg; |
| } |
| |
| /* depending on the current TBF, we assign on PACCH or AGCH */ |
| void gprs_rlcmac_trigger_downlink_assignment( |
| struct gprs_rlcmac_tbf *tbf, |
| struct gprs_rlcmac_tbf *old_tbf, const char *imsi) |
| { |
| #ifdef DEBUG_DL_ASS_IDLE |
| strncpy(debug_imsi, imsi); |
| LOGP(DRLCMAC, LOGL_ERROR, "**** DEBUGGING DOWNLINK ASSIGNMENT ****\n"); |
| #endif |
| |
| /* stop pending timer */ |
| tbf->stop_timer(); |
| |
| /* check for downlink tbf: */ |
| if (old_tbf) { |
| #ifdef DEBUG_DL_ASS_IDLE |
| LOGP(DRLCMAC, LOGL_ERROR, "We must wait for current TBF to be " |
| "released.\n"); |
| /* wait one second until assignment */ |
| tbf_timer_start(tbf, 1234, 1,0); |
| #else |
| LOGP(DRLCMAC, LOGL_DEBUG, "Send dowlink assignment on " |
| "PACCH, because %s TBF=%d exists for TLLI=0x%08x\n", |
| (old_tbf->direction == GPRS_RLCMAC_UL_TBF) |
| ? "UL" : "DL", old_tbf->tfi, old_tbf->tlli); |
| old_tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_SEND_ASS; |
| /* use TA from old TBF */ |
| tbf->ta = old_tbf->ta; |
| /* change state */ |
| tbf_new_state(tbf, GPRS_RLCMAC_ASSIGN); |
| tbf->state_flags |= (1 << GPRS_RLCMAC_FLAG_PACCH); |
| /* start timer */ |
| tbf_timer_start(tbf, 0, Tassign_pacch); |
| #endif |
| } else { |
| LOGP(DRLCMAC, LOGL_DEBUG, "Send dowlink assignment for TBF=%d on PCH, no TBF exist (IMSI=%s)\n", tbf->tfi, imsi); |
| if (!imsi || strlen(imsi) < 3) { |
| LOGP(DRLCMAC, LOGL_ERROR, "No valid IMSI!\n"); |
| return; |
| } |
| /* change state */ |
| tbf_new_state(tbf, GPRS_RLCMAC_ASSIGN); |
| tbf->state_flags |= (1 << GPRS_RLCMAC_FLAG_CCCH); |
| strncpy(tbf->dir.dl.imsi, imsi, sizeof(tbf->dir.dl.imsi)); |
| /* send immediate assignment */ |
| tbf->bts->snd_dl_ass(tbf, 0, imsi); |
| tbf->dir.dl.wait_confirm = 1; |
| } |
| } |
| |