Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 1 | /* Copied from tbf.cpp |
| 2 | * |
| 3 | * Copyright (C) 2012 Ivan Klyuchnikov |
| 4 | * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu> |
| 5 | * Copyright (C) 2013 by Holger Hans Peter Freyther |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version 2 |
| 10 | * of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 20 | */ |
| 21 | |
| 22 | #include <bts.h> |
| 23 | #include <tbf.h> |
| 24 | #include <rlc.h> |
| 25 | #include <gprs_rlcmac.h> |
| 26 | #include <gprs_debug.h> |
| 27 | #include <gprs_bssgp_pcu.h> |
| 28 | #include <decoding.h> |
| 29 | |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 30 | #include "pcu_utils.h" |
| 31 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 32 | extern "C" { |
| 33 | #include <osmocom/core/msgb.h> |
| 34 | #include <osmocom/core/talloc.h> |
| 35 | } |
| 36 | |
| 37 | #include <errno.h> |
| 38 | #include <string.h> |
| 39 | |
| 40 | /* After sending these frames, we poll for ack/nack. */ |
| 41 | #define POLL_ACK_AFTER_FRAMES 20 |
| 42 | |
| 43 | |
| 44 | static const struct gprs_rlcmac_cs gprs_rlcmac_cs[] = { |
| 45 | /* frame length data block max payload */ |
| 46 | { 0, 0, 0 }, |
| 47 | { 23, 23, 20 }, /* CS-1 */ |
| 48 | { 34, 33, 30 }, /* CS-2 */ |
| 49 | { 40, 39, 36 }, /* CS-3 */ |
| 50 | { 54, 53, 50 }, /* CS-4 */ |
| 51 | }; |
| 52 | |
| 53 | extern "C" { |
| 54 | int bssgp_tx_llc_discarded(struct bssgp_bvc_ctx *bctx, uint32_t tlli, |
| 55 | uint8_t num_frames, uint32_t num_octets); |
| 56 | } |
| 57 | |
| 58 | static inline void tbf_update_ms_class(struct gprs_rlcmac_tbf *tbf, |
| 59 | const uint8_t ms_class) |
| 60 | { |
| 61 | if (!tbf->ms_class && ms_class) |
| 62 | tbf->ms_class = ms_class; |
| 63 | } |
| 64 | |
Jacob Erlbeck | d0261b7 | 2015-04-02 13:58:09 +0200 | [diff] [blame] | 65 | static void llc_timer_cb(void *_tbf) |
| 66 | { |
| 67 | struct gprs_rlcmac_dl_tbf *tbf = (struct gprs_rlcmac_dl_tbf *)_tbf; |
| 68 | |
| 69 | if (tbf->state_is_not(GPRS_RLCMAC_FLOW)) |
| 70 | return; |
| 71 | |
| 72 | LOGP(DRLCMAC, LOGL_DEBUG, |
| 73 | "%s LLC receive timeout, requesting DL ACK\n", tbf_name(tbf)); |
| 74 | |
| 75 | tbf->request_dl_ack(); |
| 76 | } |
| 77 | |
| 78 | void gprs_rlcmac_dl_tbf::cleanup() |
| 79 | { |
| 80 | osmo_timer_del(&m_llc_timer); |
| 81 | } |
| 82 | |
| 83 | void gprs_rlcmac_dl_tbf::start_llc_timer() |
| 84 | { |
| 85 | if (bts_data()->llc_idle_ack_csec > 0) { |
| 86 | struct timeval tv; |
| 87 | |
| 88 | /* TODO: this ought to be within a constructor */ |
| 89 | m_llc_timer.data = this; |
| 90 | m_llc_timer.cb = &llc_timer_cb; |
| 91 | |
| 92 | csecs_to_timeval(bts_data()->llc_idle_ack_csec, &tv); |
| 93 | osmo_timer_schedule(&m_llc_timer, tv.tv_sec, tv.tv_usec); |
| 94 | } |
| 95 | } |
| 96 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 97 | int gprs_rlcmac_dl_tbf::append_data(const uint8_t ms_class, |
| 98 | const uint16_t pdu_delay_csec, |
| 99 | const uint8_t *data, const uint16_t len) |
| 100 | { |
| 101 | LOGP(DRLCMAC, LOGL_INFO, "%s append\n", tbf_name(this)); |
| 102 | if (state_is(GPRS_RLCMAC_WAIT_RELEASE)) { |
| 103 | LOGP(DRLCMAC, LOGL_DEBUG, |
| 104 | "%s in WAIT RELEASE state " |
| 105 | "(T3193), so reuse TBF\n", tbf_name(this)); |
| 106 | tbf_update_ms_class(this, ms_class); |
| 107 | reuse_tbf(data, len); |
Jacob Erlbeck | c495209 | 2015-03-24 11:04:19 +0100 | [diff] [blame] | 108 | } else if (!have_data()) { |
| 109 | m_llc.put_frame(data, len); |
| 110 | bts->llc_frame_sched(); |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 111 | /* it is no longer drained */ |
| 112 | m_last_dl_drained_fn = -1; |
Jacob Erlbeck | c495209 | 2015-03-24 11:04:19 +0100 | [diff] [blame] | 113 | tbf_update_ms_class(this, ms_class); |
Jacob Erlbeck | d0261b7 | 2015-04-02 13:58:09 +0200 | [diff] [blame] | 114 | start_llc_timer(); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 115 | } else { |
Jacob Erlbeck | d0261b7 | 2015-04-02 13:58:09 +0200 | [diff] [blame] | 116 | /* TODO: put this path into an llc_enqueue method */ |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 117 | /* the TBF exists, so we must write it in the queue |
| 118 | * we prepend lifetime in front of PDU */ |
| 119 | struct timeval *tv; |
| 120 | struct msgb *llc_msg = msgb_alloc(len + sizeof(*tv) * 2, |
| 121 | "llc_pdu_queue"); |
| 122 | if (!llc_msg) |
| 123 | return -ENOMEM; |
| 124 | tv = (struct timeval *)msgb_put(llc_msg, sizeof(*tv)); |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 125 | gprs_llc_queue::calc_pdu_lifetime(bts, pdu_delay_csec, tv); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 126 | tv = (struct timeval *)msgb_put(llc_msg, sizeof(*tv)); |
| 127 | gettimeofday(tv, NULL); |
| 128 | memcpy(msgb_put(llc_msg, len), data, len); |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 129 | llc_queue()->enqueue(llc_msg); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 130 | tbf_update_ms_class(this, ms_class); |
Jacob Erlbeck | d0261b7 | 2015-04-02 13:58:09 +0200 | [diff] [blame] | 131 | start_llc_timer(); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 132 | } |
| 133 | |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | static struct gprs_rlcmac_dl_tbf *tbf_lookup_dl(BTS *bts, |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 138 | const uint32_t tlli, const uint32_t tlli_old, |
| 139 | const char *imsi) |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 140 | { |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 141 | GprsMs *ms = bts->ms_store().get_ms(tlli, tlli_old, imsi); |
Jacob Erlbeck | e43460b | 2015-05-13 13:33:12 +0200 | [diff] [blame] | 142 | if (!ms) |
| 143 | return NULL; |
| 144 | |
| 145 | return ms->dl_tbf(); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 146 | } |
| 147 | |
| 148 | static int tbf_new_dl_assignment(struct gprs_rlcmac_bts *bts, |
| 149 | const char *imsi, |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 150 | const uint32_t tlli, const uint32_t tlli_old, |
| 151 | const uint8_t ms_class, |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 152 | const uint8_t *data, const uint16_t len) |
| 153 | { |
Jacob Erlbeck | 9200ce6 | 2015-05-22 17:48:04 +0200 | [diff] [blame] | 154 | uint8_t trx, ss; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 155 | int8_t use_trx; |
Jacob Erlbeck | 9200ce6 | 2015-05-22 17:48:04 +0200 | [diff] [blame] | 156 | uint16_t ta = 0; |
Jacob Erlbeck | e43460b | 2015-05-13 13:33:12 +0200 | [diff] [blame] | 157 | struct gprs_rlcmac_ul_tbf *ul_tbf = NULL, *old_ul_tbf; |
Jacob Erlbeck | 90de3a7 | 2015-04-09 19:18:59 +0200 | [diff] [blame] | 158 | struct gprs_rlcmac_dl_tbf *dl_tbf = NULL; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 159 | int8_t tfi; /* must be signed */ |
Jacob Erlbeck | e43460b | 2015-05-13 13:33:12 +0200 | [diff] [blame] | 160 | GprsMs *ms; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 161 | |
| 162 | /* check for uplink data, so we copy our informations */ |
| 163 | #warning "Do the same look up for IMSI, TLLI and OLD_TLLI" |
| 164 | #warning "Refactor the below lines... into a new method" |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 165 | ms = bts->bts->ms_store().get_ms(tlli, tlli_old, imsi); |
Jacob Erlbeck | 9200ce6 | 2015-05-22 17:48:04 +0200 | [diff] [blame] | 166 | if (ms) { |
Jacob Erlbeck | e43460b | 2015-05-13 13:33:12 +0200 | [diff] [blame] | 167 | ul_tbf = ms->ul_tbf(); |
Jacob Erlbeck | 9200ce6 | 2015-05-22 17:48:04 +0200 | [diff] [blame] | 168 | ta = ms->ta(); |
| 169 | } |
Jacob Erlbeck | e43460b | 2015-05-13 13:33:12 +0200 | [diff] [blame] | 170 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 171 | if (ul_tbf && ul_tbf->m_contention_resolution_done |
| 172 | && !ul_tbf->m_final_ack_sent) { |
| 173 | use_trx = ul_tbf->trx->trx_no; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 174 | ss = 0; |
| 175 | old_ul_tbf = ul_tbf; |
| 176 | } else { |
| 177 | use_trx = -1; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 178 | ss = 1; /* PCH assignment only allows one timeslot */ |
| 179 | old_ul_tbf = NULL; |
| 180 | } |
| 181 | |
| 182 | // Create new TBF (any TRX) |
| 183 | #warning "Copy and paste with alloc_ul_tbf" |
| 184 | tfi = bts->bts->tfi_find_free(GPRS_RLCMAC_DL_TBF, &trx, use_trx); |
Jacob Erlbeck | 90de3a7 | 2015-04-09 19:18:59 +0200 | [diff] [blame] | 185 | if (tfi >= 0) |
| 186 | /* set number of downlink slots according to multislot class */ |
| 187 | dl_tbf = tbf_alloc_dl_tbf(bts, ul_tbf, tfi, trx, ms_class, ss); |
| 188 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 189 | if (!dl_tbf) { |
| 190 | LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource\n"); |
Jacob Erlbeck | 90de3a7 | 2015-04-09 19:18:59 +0200 | [diff] [blame] | 191 | bssgp_tx_llc_discarded(gprs_bssgp_pcu_current_bctx(), tlli, |
| 192 | 1, len); |
Jacob Erlbeck | 29d91e9 | 2015-04-29 14:46:52 +0200 | [diff] [blame] | 193 | bts->bts->llc_dropped_frame(); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 194 | return -EBUSY; |
| 195 | } |
Jacob Erlbeck | be0cbc1 | 2015-05-18 14:35:11 +0200 | [diff] [blame] | 196 | dl_tbf->update_ms(tlli, GPRS_RLCMAC_DL_TBF); |
Jacob Erlbeck | 9200ce6 | 2015-05-22 17:48:04 +0200 | [diff] [blame] | 197 | dl_tbf->ms()->set_ta(ta); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 198 | |
| 199 | LOGP(DRLCMAC, LOGL_DEBUG, "%s [DOWNLINK] START\n", tbf_name(dl_tbf)); |
| 200 | |
| 201 | /* new TBF, so put first frame */ |
| 202 | dl_tbf->m_llc.put_frame(data, len); |
| 203 | dl_tbf->bts->llc_frame_sched(); |
| 204 | |
| 205 | /* Store IMSI for later look-up and PCH retransmission */ |
| 206 | dl_tbf->assign_imsi(imsi); |
| 207 | |
| 208 | /* trigger downlink assignment and set state to ASSIGN. |
| 209 | * we don't use old_downlink, so the possible uplink is used |
| 210 | * to trigger downlink assignment. if there is no uplink, |
| 211 | * AGCH is used. */ |
Jacob Erlbeck | 71e5511 | 2015-05-21 11:10:15 +0200 | [diff] [blame] | 212 | dl_tbf->bts->trigger_dl_ass(dl_tbf, old_ul_tbf); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 213 | return 0; |
| 214 | } |
| 215 | |
| 216 | /** |
| 217 | * TODO: split into unit test-able parts... |
| 218 | */ |
| 219 | int gprs_rlcmac_dl_tbf::handle(struct gprs_rlcmac_bts *bts, |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 220 | const uint32_t tlli, const uint32_t tlli_old, const char *imsi, |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 221 | const uint8_t ms_class, const uint16_t delay_csec, |
| 222 | const uint8_t *data, const uint16_t len) |
| 223 | { |
| 224 | struct gprs_rlcmac_dl_tbf *dl_tbf; |
| 225 | |
| 226 | /* check for existing TBF */ |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 227 | dl_tbf = tbf_lookup_dl(bts->bts, tlli, tlli_old, imsi); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 228 | if (dl_tbf) { |
| 229 | int rc = dl_tbf->append_data(ms_class, delay_csec, data, len); |
| 230 | if (rc >= 0) |
| 231 | dl_tbf->assign_imsi(imsi); |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 232 | |
| 233 | if (dl_tbf->ms()) |
| 234 | dl_tbf->ms()->confirm_tlli(tlli); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 235 | return rc; |
| 236 | } |
| 237 | |
Jacob Erlbeck | 9399046 | 2015-05-15 15:50:43 +0200 | [diff] [blame] | 238 | return tbf_new_dl_assignment(bts, imsi, tlli, tlli_old, ms_class, data, len); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 239 | } |
| 240 | |
| 241 | struct msgb *gprs_rlcmac_dl_tbf::llc_dequeue(bssgp_bvc_ctx *bctx) |
| 242 | { |
| 243 | struct msgb *msg; |
Jacob Erlbeck | 6e4ccec | 2015-05-06 14:24:36 +0200 | [diff] [blame] | 244 | struct timeval *tv_recv, *tv_disc; |
| 245 | struct timeval tv_now, tv_now2; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 246 | uint32_t octets = 0, frames = 0; |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 247 | struct timeval hyst_delta = {0, 0}; |
| 248 | const unsigned keep_small_thresh = 60; |
| 249 | |
| 250 | if (bts_data()->llc_discard_csec) |
| 251 | csecs_to_timeval(bts_data()->llc_discard_csec, &hyst_delta); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 252 | |
| 253 | gettimeofday(&tv_now, NULL); |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 254 | timeradd(&tv_now, &hyst_delta, &tv_now2); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 255 | |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 256 | while ((msg = llc_queue()->dequeue())) { |
Jacob Erlbeck | 6e4ccec | 2015-05-06 14:24:36 +0200 | [diff] [blame] | 257 | tv_disc = (struct timeval *)msg->data; |
| 258 | msgb_pull(msg, sizeof(*tv_disc)); |
| 259 | tv_recv = (struct timeval *)msg->data; |
| 260 | msgb_pull(msg, sizeof(*tv_recv)); |
| 261 | |
| 262 | gprs_bssgp_update_queue_delay(tv_recv, &tv_now); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 263 | |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 264 | /* Is the age below the low water mark? */ |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 265 | if (!gprs_llc_queue::is_frame_expired(&tv_now2, tv_disc)) |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 266 | break; |
| 267 | |
| 268 | /* Is the age below the high water mark */ |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 269 | if (!gprs_llc_queue::is_frame_expired(&tv_now, tv_disc)) { |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 270 | /* Has the previous message not been dropped? */ |
| 271 | if (frames == 0) |
| 272 | break; |
| 273 | |
| 274 | /* Hysteresis mode, try to discard LLC messages until |
| 275 | * the low water mark has been reached */ |
| 276 | |
| 277 | /* Check whether to abort the hysteresis mode */ |
| 278 | |
| 279 | /* Is the frame small, perhaps only a TCP ACK? */ |
| 280 | if (msg->len <= keep_small_thresh) |
| 281 | break; |
| 282 | |
| 283 | /* Is it a GMM message? */ |
| 284 | if (!gprs_llc::is_user_data_frame(msg->data, msg->len)) |
| 285 | break; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 286 | } |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 287 | |
| 288 | bts->llc_timedout_frame(); |
| 289 | frames++; |
| 290 | octets += msg->len; |
| 291 | msgb_free(msg); |
Jacob Erlbeck | 29d91e9 | 2015-04-29 14:46:52 +0200 | [diff] [blame] | 292 | bts->llc_dropped_frame(); |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 293 | continue; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 294 | } |
| 295 | |
| 296 | if (frames) { |
Jacob Erlbeck | 0c1c877 | 2015-03-20 12:02:42 +0100 | [diff] [blame] | 297 | LOGP(DRLCMACDL, LOGL_NOTICE, "%s Discarding LLC PDU " |
| 298 | "because lifetime limit reached, " |
| 299 | "count=%u new_queue_size=%zu\n", |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 300 | tbf_name(this), frames, llc_queue()->size()); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 301 | if (frames > 0xff) |
| 302 | frames = 0xff; |
| 303 | if (octets > 0xffffff) |
| 304 | octets = 0xffffff; |
Jacob Erlbeck | 767193e | 2015-05-20 12:06:46 +0200 | [diff] [blame] | 305 | bssgp_tx_llc_discarded(bctx, tlli(), frames, octets); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 306 | } |
| 307 | |
| 308 | return msg; |
| 309 | } |
| 310 | |
| 311 | /* |
| 312 | * Create DL data block |
| 313 | * The messages are fragmented and forwarded as data blocks. |
| 314 | */ |
| 315 | struct msgb *gprs_rlcmac_dl_tbf::create_dl_acked_block(uint32_t fn, uint8_t ts) |
| 316 | { |
| 317 | LOGP(DRLCMACDL, LOGL_DEBUG, "%s downlink (V(A)==%d .. " |
| 318 | "V(S)==%d)\n", tbf_name(this), |
| 319 | m_window.v_a(), m_window.v_s()); |
| 320 | |
| 321 | do_resend: |
| 322 | /* check if there is a block with negative acknowledgement */ |
| 323 | int resend_bsn = m_window.resend_needed(); |
| 324 | if (resend_bsn >= 0) { |
| 325 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Resending BSN %d\n", resend_bsn); |
| 326 | /* re-send block with negative aknowlegement */ |
| 327 | m_window.m_v_b.mark_unacked(resend_bsn); |
| 328 | bts->rlc_resent(); |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 329 | return create_dl_acked_block(fn, ts, resend_bsn); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 330 | } |
| 331 | |
| 332 | /* if the window has stalled, or transfer is complete, |
| 333 | * send an unacknowledged block */ |
Jacob Erlbeck | 9534024 | 2015-03-19 13:22:07 +0100 | [diff] [blame] | 334 | if (state_is(GPRS_RLCMAC_FINISHED)) { |
| 335 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " |
| 336 | "because all blocks have been transmitted.\n", |
| 337 | m_window.v_a()); |
| 338 | bts->rlc_restarted(); |
| 339 | } else if (dl_window_stalled()) { |
| 340 | LOGP(DRLCMACDL, LOGL_NOTICE, "- Restarting at BSN %d, " |
| 341 | "because all window is stalled.\n", |
| 342 | m_window.v_a()); |
| 343 | bts->rlc_stalled(); |
Jacob Erlbeck | e25b5b9 | 2015-03-19 14:21:33 +0100 | [diff] [blame] | 344 | } else if (have_data()) { |
| 345 | /* New blocks may be send */ |
| 346 | return create_new_bsn(fn, ts); |
| 347 | } else if (!m_window.window_empty()) { |
| 348 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " |
| 349 | "because all blocks have been transmitted (FLOW).\n", |
| 350 | m_window.v_a()); |
| 351 | bts->rlc_restarted(); |
Jacob Erlbeck | 9534024 | 2015-03-19 13:22:07 +0100 | [diff] [blame] | 352 | } else { |
Jacob Erlbeck | e25b5b9 | 2015-03-19 14:21:33 +0100 | [diff] [blame] | 353 | /* Nothing left to send, create dummy LLC commands */ |
Jacob Erlbeck | 9534024 | 2015-03-19 13:22:07 +0100 | [diff] [blame] | 354 | return create_new_bsn(fn, ts); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 355 | } |
| 356 | |
Jacob Erlbeck | 9534024 | 2015-03-19 13:22:07 +0100 | [diff] [blame] | 357 | /* If V(S) == V(A) and finished state, we would have received |
| 358 | * acknowledgement of all transmitted block. In this case we |
| 359 | * would have transmitted the final block, and received ack |
| 360 | * from MS. But in this case we did not receive the final ack |
| 361 | * indication from MS. This should never happen if MS works |
| 362 | * correctly. */ |
| 363 | if (m_window.window_empty()) { |
| 364 | LOGP(DRLCMACDL, LOGL_DEBUG, "- MS acked all blocks, " |
| 365 | "so we re-transmit final block!\n"); |
| 366 | /* we just send final block again */ |
| 367 | int16_t index = m_window.v_s_mod(-1); |
| 368 | bts->rlc_resent(); |
| 369 | return create_dl_acked_block(fn, ts, index); |
| 370 | } |
| 371 | |
| 372 | /* cycle through all unacked blocks */ |
| 373 | int resend = m_window.mark_for_resend(); |
| 374 | |
| 375 | /* At this point there should be at least one unacked block |
| 376 | * to be resent. If not, this is an software error. */ |
| 377 | if (resend == 0) { |
| 378 | LOGP(DRLCMACDL, LOGL_ERROR, "Software error: " |
| 379 | "There are no unacknowledged blocks, but V(A) " |
| 380 | " != V(S). PLEASE FIX!\n"); |
| 381 | /* we just send final block again */ |
| 382 | int16_t index = m_window.v_s_mod(-1); |
| 383 | return create_dl_acked_block(fn, ts, index); |
| 384 | } |
| 385 | goto do_resend; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 386 | } |
| 387 | |
| 388 | struct msgb *gprs_rlcmac_dl_tbf::create_new_bsn(const uint32_t fn, const uint8_t ts) |
| 389 | { |
| 390 | struct rlc_dl_header *rh; |
| 391 | struct rlc_li_field *li; |
| 392 | struct msgb *msg; |
| 393 | uint8_t *delimiter, *data, *e_pointer; |
| 394 | uint16_t space, chunk; |
| 395 | gprs_rlc_data *rlc_data; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 396 | const uint16_t bsn = m_window.v_s(); |
| 397 | |
| 398 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Sending new block at BSN %d\n", |
| 399 | m_window.v_s()); |
| 400 | |
| 401 | #warning "Selection of the CS doesn't belong here" |
| 402 | if (cs == 0) { |
| 403 | cs = bts_data()->initial_cs_dl; |
| 404 | if (cs < 1 || cs > 4) |
| 405 | cs = 1; |
| 406 | } |
| 407 | /* total length of block, including spare bits */ |
| 408 | const uint8_t block_length = gprs_rlcmac_cs[cs].block_length; |
| 409 | /* length of usable data of block, w/o spare bits, inc. MAC */ |
| 410 | const uint8_t block_data_len = gprs_rlcmac_cs[cs].block_data; |
| 411 | |
| 412 | /* now we still have untransmitted LLC data, so we fill mac block */ |
| 413 | rlc_data = m_rlc.block(bsn); |
| 414 | data = rlc_data->prepare(block_data_len); |
| 415 | |
| 416 | rh = (struct rlc_dl_header *)data; |
| 417 | rh->pt = 0; /* Data Block */ |
| 418 | rh->rrbp = rh->s_p = 0; /* Polling, set later, if required */ |
| 419 | rh->usf = 7; /* will be set at scheduler */ |
| 420 | rh->pr = 0; /* FIXME: power reduction */ |
| 421 | rh->tfi = m_tfi; /* TFI */ |
| 422 | rh->fbi = 0; /* Final Block Indicator, set late, if true */ |
| 423 | rh->bsn = bsn; /* Block Sequence Number */ |
| 424 | rh->e = 0; /* Extension bit, maybe set later */ |
| 425 | e_pointer = data + 2; /* points to E of current chunk */ |
| 426 | data += sizeof(*rh); |
| 427 | delimiter = data; /* where next length header would be stored */ |
| 428 | space = block_data_len - sizeof(*rh); |
| 429 | while (1) { |
Jacob Erlbeck | cbb1e70 | 2015-03-25 12:21:55 +0100 | [diff] [blame] | 430 | if (m_llc.frame_length() == 0) { |
| 431 | /* A header will need to by added, so we just need |
| 432 | * space-1 octets */ |
| 433 | m_llc.put_dummy_frame(space - 1); |
| 434 | |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 435 | /* The data just drained, store the current fn */ |
| 436 | if (m_last_dl_drained_fn < 0) |
| 437 | m_last_dl_drained_fn = fn; |
| 438 | |
Jacob Erlbeck | cbb1e70 | 2015-03-25 12:21:55 +0100 | [diff] [blame] | 439 | /* It is not clear, when the next real data will |
| 440 | * arrive, so request a DL ack/nack now */ |
| 441 | request_dl_ack(); |
| 442 | |
| 443 | LOGP(DRLCMACDL, LOGL_DEBUG, |
| 444 | "-- Empty chunk, " |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 445 | "added LLC dummy command of size %d, " |
| 446 | "drained_since=%d\n", |
| 447 | m_llc.frame_length(), frames_since_last_drain(fn)); |
Jacob Erlbeck | cbb1e70 | 2015-03-25 12:21:55 +0100 | [diff] [blame] | 448 | } |
| 449 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 450 | chunk = m_llc.chunk_size(); |
Jacob Erlbeck | cbb1e70 | 2015-03-25 12:21:55 +0100 | [diff] [blame] | 451 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 452 | /* if chunk will exceed block limit */ |
| 453 | if (chunk > space) { |
| 454 | LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " |
| 455 | "larger than space (%d) left in block: copy " |
| 456 | "only remaining space, and we are done\n", |
| 457 | chunk, space); |
| 458 | /* block is filled, so there is no extension */ |
| 459 | *e_pointer |= 0x01; |
| 460 | /* fill only space */ |
| 461 | m_llc.consume(data, space); |
| 462 | /* return data block as message */ |
| 463 | break; |
| 464 | } |
| 465 | /* if FINAL chunk would fit precisely in space left */ |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 466 | if (chunk == space && llc_queue()->size() == 0 && !keep_open(fn)) |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 467 | { |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 468 | LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " |
| 469 | "would exactly fit into space (%d): because " |
| 470 | "this is a final block, we don't add length " |
| 471 | "header, and we are done\n", chunk, space); |
| 472 | LOGP(DRLCMACDL, LOGL_INFO, "Complete DL frame for " |
| 473 | "%s that fits precisely in last block: " |
| 474 | "len=%d\n", tbf_name(this), m_llc.frame_length()); |
| 475 | gprs_rlcmac_dl_bw(this, m_llc.frame_length()); |
| 476 | /* block is filled, so there is no extension */ |
| 477 | *e_pointer |= 0x01; |
| 478 | /* fill space */ |
| 479 | m_llc.consume(data, space); |
| 480 | m_llc.reset(); |
| 481 | /* final block */ |
| 482 | rh->fbi = 1; /* we indicate final block */ |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 483 | request_dl_ack(); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 484 | set_state(GPRS_RLCMAC_FINISHED); |
| 485 | /* return data block as message */ |
| 486 | break; |
| 487 | } |
| 488 | /* if chunk would fit exactly in space left */ |
| 489 | if (chunk == space) { |
| 490 | LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " |
| 491 | "would exactly fit into space (%d): add length " |
| 492 | "header with LI=0, to make frame extend to " |
| 493 | "next block, and we are done\n", chunk, space); |
| 494 | /* make space for delimiter */ |
| 495 | if (delimiter != data) |
| 496 | memmove(delimiter + 1, delimiter, |
| 497 | data - delimiter); |
| 498 | data++; |
| 499 | space--; |
| 500 | /* add LI with 0 length */ |
| 501 | li = (struct rlc_li_field *)delimiter; |
| 502 | li->e = 1; /* not more extension */ |
| 503 | li->m = 0; /* shall be set to 0, in case of li = 0 */ |
| 504 | li->li = 0; /* chunk fills the complete space */ |
| 505 | // no need to set e_pointer nor increase delimiter |
| 506 | /* fill only space, which is 1 octet less than chunk */ |
| 507 | m_llc.consume(data, space); |
| 508 | /* return data block as message */ |
| 509 | break; |
| 510 | } |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 511 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 512 | LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d is less " |
| 513 | "than remaining space (%d): add length header to " |
| 514 | "to delimit LLC frame\n", chunk, space); |
| 515 | /* the LLC frame chunk ends in this block */ |
| 516 | /* make space for delimiter */ |
| 517 | if (delimiter != data) |
| 518 | memmove(delimiter + 1, delimiter, data - delimiter); |
| 519 | data++; |
| 520 | space--; |
| 521 | /* add LI to delimit frame */ |
| 522 | li = (struct rlc_li_field *)delimiter; |
| 523 | li->e = 0; /* Extension bit, maybe set later */ |
| 524 | li->m = 0; /* will be set later, if there is more LLC data */ |
| 525 | li->li = chunk; /* length of chunk */ |
| 526 | e_pointer = delimiter; /* points to E of current delimiter */ |
| 527 | delimiter++; |
| 528 | /* copy (rest of) LLC frame to space and reset later */ |
| 529 | m_llc.consume(data, chunk); |
| 530 | data += chunk; |
| 531 | space -= chunk; |
| 532 | LOGP(DRLCMACDL, LOGL_INFO, "Complete DL frame for %s" |
| 533 | "len=%d\n", tbf_name(this), m_llc.frame_length()); |
| 534 | gprs_rlcmac_dl_bw(this, m_llc.frame_length()); |
| 535 | m_llc.reset(); |
| 536 | /* dequeue next LLC frame, if any */ |
| 537 | msg = llc_dequeue(gprs_bssgp_pcu_current_bctx()); |
| 538 | if (msg) { |
| 539 | LOGP(DRLCMACDL, LOGL_INFO, "- Dequeue next LLC for " |
| 540 | "%s (len=%d)\n", tbf_name(this), msg->len); |
| 541 | m_llc.put_frame(msg->data, msg->len); |
| 542 | bts->llc_frame_sched(); |
| 543 | msgb_free(msg); |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 544 | m_last_dl_drained_fn = -1; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 545 | } |
| 546 | /* if we have more data and we have space left */ |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 547 | if (space > 0 && (m_llc.frame_length() || keep_open(fn))) { |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 548 | li->m = 1; /* we indicate more frames to follow */ |
| 549 | continue; |
| 550 | } |
| 551 | /* if we don't have more LLC frames */ |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 552 | if (!m_llc.frame_length() && !keep_open(fn)) { |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 553 | LOGP(DRLCMACDL, LOGL_DEBUG, "-- Final block, so we " |
| 554 | "done.\n"); |
| 555 | li->e = 1; /* we cannot extend */ |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 556 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 557 | rh->fbi = 1; /* we indicate final block */ |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 558 | request_dl_ack(); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 559 | set_state(GPRS_RLCMAC_FINISHED); |
| 560 | break; |
| 561 | } |
| 562 | /* we have no space left */ |
| 563 | LOGP(DRLCMACDL, LOGL_DEBUG, "-- No space left, so we are " |
| 564 | "done.\n"); |
| 565 | li->e = 1; /* we cannot extend */ |
| 566 | break; |
| 567 | } |
| 568 | LOGP(DRLCMACDL, LOGL_DEBUG, "data block: %s\n", |
| 569 | osmo_hexdump(rlc_data->block, block_length)); |
| 570 | #warning "move this up?" |
| 571 | rlc_data->len = block_length; |
| 572 | /* raise send state and set ack state array */ |
| 573 | m_window.m_v_b.mark_unacked(bsn); |
| 574 | m_window.increment_send(); |
| 575 | |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 576 | return create_dl_acked_block(fn, ts, bsn); |
| 577 | } |
| 578 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 579 | struct msgb *gprs_rlcmac_dl_tbf::create_dl_acked_block( |
| 580 | const uint32_t fn, const uint8_t ts, |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 581 | const int index) |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 582 | { |
| 583 | uint8_t *data; |
| 584 | struct rlc_dl_header *rh; |
| 585 | struct msgb *dl_msg; |
| 586 | uint8_t len; |
Daniel Willmann | efd5dbb | 2014-08-25 16:20:23 +0200 | [diff] [blame] | 587 | bool need_poll; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 588 | |
| 589 | /* get data and header from current block */ |
| 590 | data = m_rlc.block(index)->block; |
| 591 | len = m_rlc.block(index)->len; |
| 592 | rh = (struct rlc_dl_header *)data; |
| 593 | |
Jacob Erlbeck | 005ee7f | 2015-03-20 14:53:54 +0100 | [diff] [blame] | 594 | /* If the TBF has just started, relate frames_since_last_poll to the |
| 595 | * current fn */ |
| 596 | if (m_last_dl_poll_fn < 0) |
| 597 | m_last_dl_poll_fn = fn; |
| 598 | |
Daniel Willmann | efd5dbb | 2014-08-25 16:20:23 +0200 | [diff] [blame] | 599 | need_poll = state_flags & (1 << GPRS_RLCMAC_FLAG_TO_DL_ACK); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 600 | /* Clear Polling, if still set in history buffer */ |
| 601 | rh->s_p = 0; |
| 602 | |
| 603 | /* poll after POLL_ACK_AFTER_FRAMES frames, or when final block is tx. |
| 604 | */ |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 605 | if (m_tx_counter >= POLL_ACK_AFTER_FRAMES || m_dl_ack_requested || |
Daniel Willmann | efd5dbb | 2014-08-25 16:20:23 +0200 | [diff] [blame] | 606 | need_poll) { |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 607 | if (m_dl_ack_requested) { |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 608 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 609 | "polling, because is was requested explicitly " |
| 610 | "(e.g. first final block sent).\n"); |
Daniel Willmann | efd5dbb | 2014-08-25 16:20:23 +0200 | [diff] [blame] | 611 | } else if (need_poll) { |
| 612 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " |
Daniel Willmann | 635d47c | 2014-09-17 17:58:29 +0200 | [diff] [blame] | 613 | "polling, because polling timed out.\n"); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 614 | } else { |
| 615 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " |
| 616 | "polling, because %d blocks sent.\n", |
| 617 | POLL_ACK_AFTER_FRAMES); |
| 618 | } |
| 619 | /* scheduling not possible, because: */ |
| 620 | if (poll_state != GPRS_RLCMAC_POLL_NONE) |
| 621 | LOGP(DRLCMACDL, LOGL_DEBUG, "Polling is already " |
| 622 | "sheduled for %s, so we must wait for " |
| 623 | "requesting downlink ack\n", tbf_name(this)); |
| 624 | else if (control_ts != ts) |
| 625 | LOGP(DRLCMACDL, LOGL_DEBUG, "Polling cannot be " |
| 626 | "sheduled in this TS %d, waiting for " |
| 627 | "TS %d\n", ts, control_ts); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 628 | else if (bts->sba()->find(trx->trx_no, ts, (fn + 13) % 2715648)) |
| 629 | LOGP(DRLCMACDL, LOGL_DEBUG, "Polling cannot be " |
| 630 | "sheduled, because single block alllocation " |
| 631 | "already exists\n"); |
| 632 | else { |
| 633 | LOGP(DRLCMACDL, LOGL_DEBUG, "Polling sheduled in this " |
| 634 | "TS %d\n", ts); |
| 635 | m_tx_counter = 0; |
| 636 | /* start timer whenever we send the final block */ |
| 637 | if (rh->fbi == 1) |
| 638 | tbf_timer_start(this, 3191, bts_data()->t3191, 0); |
| 639 | |
| 640 | /* schedule polling */ |
| 641 | poll_state = GPRS_RLCMAC_POLL_SCHED; |
| 642 | poll_fn = (fn + 13) % 2715648; |
| 643 | |
Daniel Willmann | efd5dbb | 2014-08-25 16:20:23 +0200 | [diff] [blame] | 644 | /* Clear poll timeout flag */ |
| 645 | state_flags &= ~(1 << GPRS_RLCMAC_FLAG_TO_DL_ACK); |
| 646 | |
Jacob Erlbeck | 7c44415 | 2015-03-12 12:08:54 +0100 | [diff] [blame] | 647 | /* Clear request flag */ |
| 648 | m_dl_ack_requested = false; |
| 649 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 650 | /* set polling in header */ |
| 651 | rh->rrbp = 0; /* N+13 */ |
| 652 | rh->s_p = 1; /* Polling */ |
Jacob Erlbeck | 005ee7f | 2015-03-20 14:53:54 +0100 | [diff] [blame] | 653 | |
| 654 | m_last_dl_poll_fn = poll_fn; |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 655 | } |
| 656 | } |
| 657 | |
| 658 | /* return data block as message */ |
| 659 | dl_msg = msgb_alloc(len, "rlcmac_dl_data"); |
| 660 | if (!dl_msg) |
| 661 | return NULL; |
| 662 | |
| 663 | /* Increment TX-counter */ |
| 664 | m_tx_counter++; |
| 665 | |
| 666 | memcpy(msgb_put(dl_msg, len), data, len); |
| 667 | bts->rlc_sent(); |
| 668 | |
| 669 | return dl_msg; |
| 670 | } |
| 671 | |
| 672 | int gprs_rlcmac_dl_tbf::update_window(const uint8_t ssn, const uint8_t *rbb) |
| 673 | { |
| 674 | int16_t dist; /* must be signed */ |
| 675 | uint16_t lost = 0, received = 0; |
| 676 | char show_rbb[65]; |
| 677 | char show_v_b[RLC_MAX_SNS + 1]; |
| 678 | const uint16_t mod_sns = m_window.mod_sns(); |
| 679 | |
| 680 | Decoding::extract_rbb(rbb, show_rbb); |
| 681 | /* show received array in debug (bit 64..1) */ |
| 682 | LOGP(DRLCMACDL, LOGL_DEBUG, "- ack: (BSN=%d)\"%s\"" |
| 683 | "(BSN=%d) R=ACK I=NACK\n", (ssn - 64) & mod_sns, |
| 684 | show_rbb, (ssn - 1) & mod_sns); |
| 685 | |
| 686 | /* apply received array to receive state (SSN-64..SSN-1) */ |
| 687 | /* calculate distance of ssn from V(S) */ |
| 688 | dist = (m_window.v_s() - ssn) & mod_sns; |
| 689 | /* check if distance is less than distance V(A)..V(S) */ |
| 690 | if (dist >= m_window.distance()) { |
| 691 | /* this might happpen, if the downlink assignment |
| 692 | * was not received by ms and the ack refers |
| 693 | * to previous TBF |
| 694 | * FIXME: we should implement polling for |
| 695 | * control ack!*/ |
| 696 | LOGP(DRLCMACDL, LOGL_NOTICE, "- ack range is out of " |
| 697 | "V(A)..V(S) range %s Free TBF!\n", tbf_name(this)); |
| 698 | return 1; /* indicate to free TBF */ |
| 699 | } |
| 700 | |
| 701 | m_window.update(bts, show_rbb, ssn, |
| 702 | &lost, &received); |
| 703 | |
| 704 | /* report lost and received packets */ |
| 705 | gprs_rlcmac_received_lost(this, received, lost); |
| 706 | |
| 707 | /* raise V(A), if possible */ |
| 708 | m_window.raise(m_window.move_window()); |
| 709 | |
| 710 | /* show receive state array in debug (V(A)..V(S)-1) */ |
| 711 | m_window.show_state(show_v_b); |
| 712 | LOGP(DRLCMACDL, LOGL_DEBUG, "- V(B): (V(A)=%d)\"%s\"" |
| 713 | "(V(S)-1=%d) A=Acked N=Nacked U=Unacked " |
| 714 | "X=Resend-Unacked I=Invalid\n", |
| 715 | m_window.v_a(), show_v_b, |
| 716 | m_window.v_s_mod(-1)); |
| 717 | |
| 718 | if (state_is(GPRS_RLCMAC_FINISHED) && m_window.window_empty()) { |
| 719 | LOGP(DRLCMACDL, LOGL_NOTICE, "Received acknowledge of " |
| 720 | "all blocks, but without final ack " |
| 721 | "inidcation (don't worry)\n"); |
| 722 | } |
| 723 | return 0; |
| 724 | } |
| 725 | |
| 726 | |
| 727 | int gprs_rlcmac_dl_tbf::maybe_start_new_window() |
| 728 | { |
| 729 | struct msgb *msg; |
| 730 | uint16_t received; |
| 731 | |
| 732 | LOGP(DRLCMACDL, LOGL_DEBUG, "- Final ACK received.\n"); |
| 733 | /* range V(A)..V(S)-1 */ |
| 734 | received = m_window.count_unacked(); |
| 735 | |
| 736 | /* report all outstanding packets as received */ |
| 737 | gprs_rlcmac_received_lost(this, received, 0); |
| 738 | |
| 739 | set_state(GPRS_RLCMAC_WAIT_RELEASE); |
| 740 | |
| 741 | /* check for LLC PDU in the LLC Queue */ |
| 742 | msg = llc_dequeue(gprs_bssgp_pcu_current_bctx()); |
| 743 | if (!msg) { |
| 744 | /* no message, start T3193, change state to RELEASE */ |
| 745 | LOGP(DRLCMACDL, LOGL_DEBUG, "- No new message, so we release.\n"); |
| 746 | /* start T3193 */ |
| 747 | tbf_timer_start(this, 3193, |
| 748 | bts_data()->t3193_msec / 1000, |
| 749 | (bts_data()->t3193_msec % 1000) * 1000); |
| 750 | |
| 751 | return 0; |
| 752 | } |
| 753 | |
| 754 | /* we have more data so we will re-use this tbf */ |
| 755 | reuse_tbf(msg->data, msg->len); |
| 756 | msgb_free(msg); |
| 757 | return 0; |
| 758 | } |
| 759 | |
| 760 | int gprs_rlcmac_dl_tbf::rcvd_dl_ack(uint8_t final_ack, uint8_t ssn, uint8_t *rbb) |
| 761 | { |
| 762 | LOGP(DRLCMACDL, LOGL_DEBUG, "%s downlink acknowledge\n", tbf_name(this)); |
| 763 | |
| 764 | if (!final_ack) |
| 765 | return update_window(ssn, rbb); |
| 766 | return maybe_start_new_window(); |
| 767 | } |
| 768 | |
| 769 | void gprs_rlcmac_dl_tbf::reuse_tbf(const uint8_t *data, const uint16_t len) |
| 770 | { |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 771 | uint8_t trx; |
Jacob Erlbeck | 90de3a7 | 2015-04-09 19:18:59 +0200 | [diff] [blame] | 772 | struct gprs_rlcmac_dl_tbf *new_tbf = NULL; |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 773 | int8_t tfi; /* must be signed */ |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 774 | struct msgb *msg; |
| 775 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 776 | bts->tbf_reused(); |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 777 | |
| 778 | tfi = bts->tfi_find_free(GPRS_RLCMAC_DL_TBF, &trx, this->trx->trx_no); |
Jacob Erlbeck | 90de3a7 | 2015-04-09 19:18:59 +0200 | [diff] [blame] | 779 | if (tfi >= 0) |
| 780 | new_tbf = tbf_alloc_dl_tbf(bts->bts_data(), NULL, tfi, trx, |
| 781 | ms_class, 0); |
| 782 | |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 783 | if (!new_tbf) { |
| 784 | LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource\n"); |
Jacob Erlbeck | 767193e | 2015-05-20 12:06:46 +0200 | [diff] [blame] | 785 | bssgp_tx_llc_discarded(gprs_bssgp_pcu_current_bctx(), tlli(), |
Jacob Erlbeck | 90de3a7 | 2015-04-09 19:18:59 +0200 | [diff] [blame] | 786 | 1, len); |
Jacob Erlbeck | 29d91e9 | 2015-04-29 14:46:52 +0200 | [diff] [blame] | 787 | bts->llc_dropped_frame(); |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 788 | return; |
| 789 | } |
| 790 | |
Jacob Erlbeck | 4f45979 | 2015-05-18 15:21:36 +0200 | [diff] [blame] | 791 | new_tbf->set_ms(ms()); |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 792 | |
| 793 | /* Copy over all data to the new TBF */ |
| 794 | new_tbf->m_llc.put_frame(data, len); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 795 | bts->llc_frame_sched(); |
| 796 | |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 797 | while ((msg = llc_queue()->dequeue())) |
| 798 | new_tbf->llc_queue()->enqueue(msg); |
Daniel Willmann | e481815 | 2014-08-15 16:52:09 +0200 | [diff] [blame] | 799 | |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 800 | /* reset rlc states */ |
| 801 | m_tx_counter = 0; |
| 802 | m_wait_confirm = 0; |
| 803 | m_window.reset(); |
| 804 | |
| 805 | /* keep to flags */ |
| 806 | state_flags &= GPRS_RLCMAC_FLAG_TO_MASK; |
| 807 | state_flags &= ~(1 << GPRS_RLCMAC_FLAG_CCCH); |
| 808 | |
| 809 | update(); |
| 810 | |
| 811 | LOGP(DRLCMAC, LOGL_DEBUG, "%s Trigger dowlink assignment on PACCH, " |
| 812 | "because another LLC PDU has arrived in between\n", |
| 813 | tbf_name(this)); |
Jacob Erlbeck | 71e5511 | 2015-05-21 11:10:15 +0200 | [diff] [blame] | 814 | bts->trigger_dl_ass(new_tbf, this); |
Daniel Willmann | ca102af | 2014-08-08 12:14:12 +0200 | [diff] [blame] | 815 | } |
| 816 | |
| 817 | bool gprs_rlcmac_dl_tbf::dl_window_stalled() const |
| 818 | { |
| 819 | return m_window.window_stalled(); |
| 820 | } |
| 821 | |
Jacob Erlbeck | eceb910 | 2015-03-20 14:41:50 +0100 | [diff] [blame] | 822 | void gprs_rlcmac_dl_tbf::request_dl_ack() |
| 823 | { |
| 824 | m_dl_ack_requested = true; |
| 825 | } |
| 826 | |
| 827 | bool gprs_rlcmac_dl_tbf::need_control_ts() const |
| 828 | { |
| 829 | if (poll_state != GPRS_RLCMAC_POLL_NONE) |
| 830 | return false; |
| 831 | |
| 832 | return state_flags & (1 << GPRS_RLCMAC_FLAG_TO_DL_ACK) || |
| 833 | m_tx_counter >= POLL_ACK_AFTER_FRAMES || |
| 834 | m_dl_ack_requested; |
| 835 | } |
| 836 | |
| 837 | bool gprs_rlcmac_dl_tbf::have_data() const |
| 838 | { |
Jacob Erlbeck | 6dbe822 | 2015-05-29 10:37:09 +0200 | [diff] [blame] | 839 | return m_llc.chunk_size() > 0 || llc_queue()->size() > 0; |
Jacob Erlbeck | eceb910 | 2015-03-20 14:41:50 +0100 | [diff] [blame] | 840 | } |
Jacob Erlbeck | 005ee7f | 2015-03-20 14:53:54 +0100 | [diff] [blame] | 841 | |
| 842 | int gprs_rlcmac_dl_tbf::frames_since_last_poll(unsigned fn) const |
| 843 | { |
| 844 | unsigned wrapped; |
| 845 | if (m_last_dl_poll_fn < 0) |
| 846 | return -1; |
| 847 | |
| 848 | wrapped = (fn + 2715648 - m_last_dl_poll_fn) % 2715648; |
| 849 | if (wrapped < 2715648/2) |
| 850 | return wrapped; |
| 851 | else |
| 852 | return wrapped - 2715648; |
| 853 | } |
| 854 | |
Jacob Erlbeck | 3bed5d1 | 2015-03-19 11:22:38 +0100 | [diff] [blame] | 855 | int gprs_rlcmac_dl_tbf::frames_since_last_drain(unsigned fn) const |
| 856 | { |
| 857 | unsigned wrapped; |
| 858 | if (m_last_dl_drained_fn < 0) |
| 859 | return -1; |
| 860 | |
| 861 | wrapped = (fn + 2715648 - m_last_dl_drained_fn) % 2715648; |
| 862 | if (wrapped < 2715648/2) |
| 863 | return wrapped; |
| 864 | else |
| 865 | return wrapped - 2715648; |
| 866 | } |
| 867 | |
| 868 | bool gprs_rlcmac_dl_tbf::keep_open(unsigned fn) const |
| 869 | { |
| 870 | int keep_time_frames; |
| 871 | |
| 872 | if (bts_data()->dl_tbf_idle_msec <= 0) |
| 873 | return false; |
| 874 | |
| 875 | keep_time_frames = msecs_to_frames(bts_data()->dl_tbf_idle_msec); |
| 876 | return frames_since_last_drain(fn) <= keep_time_frames; |
| 877 | } |