Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 1 | /* GSM Channel allocation routines |
| 2 | * |
| 3 | * (C) 2008 by Harald Welte <laforge@gnumonks.org> |
| 4 | * (C) 2008, 2009 by Holger Hans Peter Freyther <zecke@selfish.org> |
| 5 | * |
| 6 | * All Rights Reserved |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; either version 2 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License along |
| 19 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 20 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 21 | * |
| 22 | */ |
| 23 | |
| 24 | #include <stdio.h> |
| 25 | #include <stdlib.h> |
| 26 | #include <string.h> |
| 27 | #include <errno.h> |
| 28 | |
| 29 | #include <openbsc/gsm_data.h> |
| 30 | #include <openbsc/chan_alloc.h> |
| 31 | #include <openbsc/abis_nm.h> |
| 32 | #include <openbsc/abis_rsl.h> |
| 33 | #include <openbsc/debug.h> |
| 34 | #include <openbsc/signal.h> |
| 35 | |
| 36 | static void auto_release_channel(void *_lchan); |
| 37 | |
| 38 | struct gsm_bts_trx_ts *ts_c0_alloc(struct gsm_bts *bts, |
| 39 | enum gsm_phys_chan_config pchan) |
| 40 | { |
Harald Welte | e712a5f | 2009-06-21 16:17:15 +0200 | [diff] [blame] | 41 | struct gsm_bts_trx *trx = bts->c0; |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 42 | struct gsm_bts_trx_ts *ts = &trx->ts[0]; |
| 43 | |
| 44 | if (pchan != GSM_PCHAN_CCCH && |
| 45 | pchan != GSM_PCHAN_CCCH_SDCCH4) |
| 46 | return NULL; |
| 47 | |
| 48 | if (ts->pchan != GSM_PCHAN_NONE) |
| 49 | return NULL; |
| 50 | |
| 51 | ts->pchan = pchan; |
| 52 | |
| 53 | return ts; |
| 54 | } |
| 55 | |
Harald Welte | 0374084 | 2009-06-10 23:11:52 +0800 | [diff] [blame] | 56 | /* Allocate a physical channel (TS) */ |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 57 | struct gsm_bts_trx_ts *ts_alloc(struct gsm_bts *bts, |
| 58 | enum gsm_phys_chan_config pchan) |
| 59 | { |
Harald Welte | 351ff12 | 2009-08-10 13:25:55 +0200 | [diff] [blame] | 60 | int j; |
| 61 | struct gsm_bts_trx *trx; |
| 62 | |
| 63 | llist_for_each_entry(trx, &bts->trx_list, list) { |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 64 | int from, to; |
| 65 | |
| 66 | /* the following constraints are pure policy, |
| 67 | * no requirement to put this restriction in place */ |
Harald Welte | 3a9c2c0 | 2009-07-29 16:46:37 +0200 | [diff] [blame] | 68 | if (trx == bts->c0) { |
| 69 | /* On the first TRX we run one CCCH and one SDCCH8 */ |
| 70 | switch (pchan) { |
| 71 | case GSM_PCHAN_CCCH: |
| 72 | case GSM_PCHAN_CCCH_SDCCH4: |
| 73 | from = 0; to = 0; |
| 74 | break; |
Harald Welte | 3a9c2c0 | 2009-07-29 16:46:37 +0200 | [diff] [blame] | 75 | case GSM_PCHAN_TCH_F: |
| 76 | case GSM_PCHAN_TCH_H: |
Harald Welte | 7f863f5 | 2009-08-09 22:01:26 +0200 | [diff] [blame] | 77 | from = 1; to = 7; |
Harald Welte | 3a9c2c0 | 2009-07-29 16:46:37 +0200 | [diff] [blame] | 78 | break; |
Harald Welte | 7f863f5 | 2009-08-09 22:01:26 +0200 | [diff] [blame] | 79 | case GSM_PCHAN_SDCCH8_SACCH8C: |
Harald Welte | 3a9c2c0 | 2009-07-29 16:46:37 +0200 | [diff] [blame] | 80 | default: |
| 81 | return NULL; |
| 82 | } |
| 83 | } else { |
| 84 | /* Every secondary TRX is configured for TCH/F |
| 85 | * and TCH/H only */ |
| 86 | switch (pchan) { |
Harald Welte | 7f863f5 | 2009-08-09 22:01:26 +0200 | [diff] [blame] | 87 | case GSM_PCHAN_SDCCH8_SACCH8C: |
| 88 | from = 1; to = 1; |
Harald Welte | 3a9c2c0 | 2009-07-29 16:46:37 +0200 | [diff] [blame] | 89 | case GSM_PCHAN_TCH_F: |
| 90 | case GSM_PCHAN_TCH_H: |
Harald Welte | 7f863f5 | 2009-08-09 22:01:26 +0200 | [diff] [blame] | 91 | from = 1; to = 7; |
Harald Welte | 3a9c2c0 | 2009-07-29 16:46:37 +0200 | [diff] [blame] | 92 | break; |
| 93 | default: |
| 94 | return NULL; |
| 95 | } |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 96 | } |
| 97 | |
| 98 | for (j = from; j <= to; j++) { |
| 99 | struct gsm_bts_trx_ts *ts = &trx->ts[j]; |
| 100 | if (ts->pchan == GSM_PCHAN_NONE) { |
| 101 | ts->pchan = pchan; |
| 102 | /* set channel attribute on OML */ |
Harald Welte | 35cd5e9 | 2009-08-10 12:21:22 +0200 | [diff] [blame] | 103 | abis_nm_set_channel_attr(ts, abis_nm_chcomb4pchan(pchan)); |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 104 | return ts; |
| 105 | } |
| 106 | } |
| 107 | } |
| 108 | return NULL; |
| 109 | } |
| 110 | |
| 111 | /* Free a physical channel (TS) */ |
| 112 | void ts_free(struct gsm_bts_trx_ts *ts) |
| 113 | { |
| 114 | ts->pchan = GSM_PCHAN_NONE; |
| 115 | } |
| 116 | |
| 117 | static const u_int8_t subslots_per_pchan[] = { |
| 118 | [GSM_PCHAN_NONE] = 0, |
| 119 | [GSM_PCHAN_CCCH] = 0, |
| 120 | [GSM_PCHAN_CCCH_SDCCH4] = 4, |
| 121 | [GSM_PCHAN_TCH_F] = 1, |
| 122 | [GSM_PCHAN_TCH_H] = 2, |
Harald Welte | 0374084 | 2009-06-10 23:11:52 +0800 | [diff] [blame] | 123 | [GSM_PCHAN_SDCCH8_SACCH8C] = 8, |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 124 | }; |
| 125 | |
| 126 | static struct gsm_lchan * |
Harald Welte | ceb3c04 | 2009-08-10 13:46:55 +0200 | [diff] [blame] | 127 | _lc_find_trx(struct gsm_bts_trx *trx, enum gsm_phys_chan_config pchan) |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 128 | { |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 129 | struct gsm_bts_trx_ts *ts; |
Harald Welte | 351ff12 | 2009-08-10 13:25:55 +0200 | [diff] [blame] | 130 | int j, ss; |
| 131 | |
Harald Welte | ceb3c04 | 2009-08-10 13:46:55 +0200 | [diff] [blame] | 132 | for (j = 0; j < 8; j++) { |
| 133 | ts = &trx->ts[j]; |
| 134 | if (ts->pchan != pchan) |
| 135 | continue; |
| 136 | /* check if all sub-slots are allocated yet */ |
| 137 | for (ss = 0; ss < subslots_per_pchan[pchan]; ss++) { |
| 138 | struct gsm_lchan *lc = &ts->lchan[ss]; |
| 139 | if (lc->type == GSM_LCHAN_NONE) |
| 140 | return lc; |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 141 | } |
| 142 | } |
Harald Welte | ceb3c04 | 2009-08-10 13:46:55 +0200 | [diff] [blame] | 143 | return NULL; |
| 144 | } |
| 145 | |
| 146 | static struct gsm_lchan * |
| 147 | _lc_find_bts(struct gsm_bts *bts, enum gsm_phys_chan_config pchan) |
| 148 | { |
| 149 | struct gsm_bts_trx *trx; |
| 150 | struct gsm_bts_trx_ts *ts; |
| 151 | struct gsm_lchan *lc; |
| 152 | |
| 153 | if (bts->chan_alloc_reverse) { |
| 154 | llist_for_each_entry_reverse(trx, &bts->trx_list, list) { |
| 155 | lc = _lc_find_trx(trx, pchan); |
| 156 | if (lc) |
| 157 | return lc; |
| 158 | } |
| 159 | } else { |
| 160 | llist_for_each_entry(trx, &bts->trx_list, list) { |
| 161 | lc = _lc_find_trx(trx, pchan); |
| 162 | if (lc) |
| 163 | return lc; |
| 164 | } |
| 165 | } |
| 166 | |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 167 | /* we cannot allocate more of these */ |
| 168 | if (pchan == GSM_PCHAN_CCCH_SDCCH4) |
| 169 | return NULL; |
| 170 | |
| 171 | /* if we've reached here, we need to allocate a new physical |
| 172 | * channel for the logical channel type requested */ |
| 173 | ts = ts_alloc(bts, pchan); |
| 174 | if (!ts) { |
| 175 | /* no more radio resources */ |
| 176 | return NULL; |
| 177 | } |
| 178 | return &ts->lchan[0]; |
| 179 | } |
| 180 | |
| 181 | /* Allocate a logical channel */ |
| 182 | struct gsm_lchan *lchan_alloc(struct gsm_bts *bts, enum gsm_chan_t type) |
| 183 | { |
| 184 | struct gsm_lchan *lchan = NULL; |
Harald Welte | af86c0f | 2009-08-10 14:44:24 +0200 | [diff] [blame] | 185 | enum gsm_phys_chan_config first, second; |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 186 | |
| 187 | switch (type) { |
| 188 | case GSM_LCHAN_SDCCH: |
Harald Welte | af86c0f | 2009-08-10 14:44:24 +0200 | [diff] [blame] | 189 | if (bts->chan_alloc_reverse) { |
| 190 | first = GSM_PCHAN_SDCCH8_SACCH8C; |
| 191 | second = GSM_PCHAN_CCCH_SDCCH4; |
| 192 | } else { |
| 193 | first = GSM_PCHAN_CCCH_SDCCH4; |
| 194 | second = GSM_PCHAN_SDCCH8_SACCH8C; |
| 195 | } |
| 196 | |
| 197 | lchan = _lc_find_bts(bts, first); |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 198 | if (lchan == NULL) |
Harald Welte | af86c0f | 2009-08-10 14:44:24 +0200 | [diff] [blame] | 199 | lchan = _lc_find_bts(bts, second); |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 200 | break; |
| 201 | case GSM_LCHAN_TCH_F: |
Harald Welte | ceb3c04 | 2009-08-10 13:46:55 +0200 | [diff] [blame] | 202 | lchan = _lc_find_bts(bts, GSM_PCHAN_TCH_F); |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 203 | break; |
| 204 | case GSM_LCHAN_TCH_H: |
Harald Welte | ceb3c04 | 2009-08-10 13:46:55 +0200 | [diff] [blame] | 205 | lchan =_lc_find_bts(bts, GSM_PCHAN_TCH_H); |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 206 | break; |
| 207 | default: |
| 208 | fprintf(stderr, "Unknown gsm_chan_t %u\n", type); |
| 209 | } |
| 210 | |
| 211 | if (lchan) { |
| 212 | lchan->type = type; |
| 213 | lchan->use_count = 0; |
| 214 | |
Holger Hans Peter Freyther | d831805 | 2009-10-28 14:23:39 +0100 | [diff] [blame] | 215 | /* clear sapis */ |
| 216 | memset(lchan->sapis, 0, sizeof(lchan->sapis)); |
| 217 | |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 218 | /* Configure the time and start it so it will be closed */ |
| 219 | lchan->release_timer.cb = auto_release_channel; |
| 220 | lchan->release_timer.data = lchan; |
| 221 | bsc_schedule_timer(&lchan->release_timer, LCHAN_RELEASE_TIMEOUT); |
| 222 | } |
| 223 | |
| 224 | return lchan; |
| 225 | } |
| 226 | |
| 227 | /* Free a logical channel */ |
| 228 | void lchan_free(struct gsm_lchan *lchan) |
| 229 | { |
| 230 | lchan->type = GSM_LCHAN_NONE; |
| 231 | if (lchan->subscr) { |
| 232 | subscr_put(lchan->subscr); |
Holger Hans Peter Freyther | 3265b1a | 2009-10-27 10:42:53 +0100 | [diff] [blame] | 233 | lchan->subscr = NULL; |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 234 | } |
| 235 | |
| 236 | /* We might kill an active channel... */ |
| 237 | if (lchan->use_count != 0) { |
| 238 | dispatch_signal(SS_LCHAN, S_LCHAN_UNEXPECTED_RELEASE, lchan); |
| 239 | lchan->use_count = 0; |
| 240 | } |
| 241 | |
| 242 | /* stop the timer */ |
| 243 | bsc_del_timer(&lchan->release_timer); |
| 244 | |
| 245 | /* FIXME: ts_free() the timeslot, if we're the last logical |
| 246 | * channel using it */ |
| 247 | } |
| 248 | |
| 249 | /* Consider releasing the channel now */ |
| 250 | int lchan_auto_release(struct gsm_lchan *lchan) |
| 251 | { |
| 252 | if (lchan->use_count > 0) { |
| 253 | return 0; |
| 254 | } |
| 255 | |
| 256 | /* Assume we have GSM04.08 running and send a release */ |
| 257 | if (lchan->subscr) { |
| 258 | gsm48_send_rr_release(lchan); |
| 259 | } |
| 260 | |
| 261 | /* spoofed? message */ |
| 262 | if (lchan->use_count < 0) { |
| 263 | DEBUGP(DRLL, "Channel count is negative: %d\n", lchan->use_count); |
| 264 | } |
| 265 | |
| 266 | DEBUGP(DRLL, "Recycling the channel with: %d (%x)\n", lchan->nr, lchan->nr); |
Harald Welte | 0f2e3c1 | 2009-08-08 13:15:07 +0200 | [diff] [blame] | 267 | rsl_release_request(lchan, 0); |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 268 | return 1; |
| 269 | } |
| 270 | |
| 271 | /* Auto release the channel when the use count is zero */ |
| 272 | static void auto_release_channel(void *_lchan) |
| 273 | { |
| 274 | struct gsm_lchan *lchan = _lchan; |
| 275 | |
| 276 | if (!lchan_auto_release(lchan)) |
| 277 | bsc_schedule_timer(&lchan->release_timer, LCHAN_RELEASE_TIMEOUT); |
| 278 | } |
| 279 | |
| 280 | struct gsm_lchan* lchan_find(struct gsm_bts *bts, struct gsm_subscriber *subscr) { |
Harald Welte | e712a5f | 2009-06-21 16:17:15 +0200 | [diff] [blame] | 281 | struct gsm_bts_trx *trx; |
| 282 | int ts_no, lchan_no; |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 283 | |
Harald Welte | e712a5f | 2009-06-21 16:17:15 +0200 | [diff] [blame] | 284 | llist_for_each_entry(trx, &bts->trx_list, list) { |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 285 | for (ts_no = 0; ts_no < 8; ++ts_no) { |
| 286 | for (lchan_no = 0; lchan_no < TS_MAX_LCHAN; ++lchan_no) { |
| 287 | struct gsm_lchan *lchan = |
Harald Welte | e712a5f | 2009-06-21 16:17:15 +0200 | [diff] [blame] | 288 | &trx->ts[ts_no].lchan[lchan_no]; |
Harald Welte | 59b0468 | 2009-06-10 05:40:52 +0800 | [diff] [blame] | 289 | if (subscr == lchan->subscr) |
| 290 | return lchan; |
| 291 | } |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | return NULL; |
| 296 | } |
Harald Welte | aa60edb | 2009-08-09 18:52:33 +0200 | [diff] [blame] | 297 | |
| 298 | struct gsm_lchan *lchan_for_subscr(struct gsm_subscriber *subscr) |
| 299 | { |
| 300 | struct gsm_bts *bts; |
| 301 | struct gsm_network *net = subscr->net; |
| 302 | struct gsm_lchan *lchan; |
| 303 | |
| 304 | llist_for_each_entry(bts, &net->bts_list, list) { |
| 305 | lchan = lchan_find(bts, subscr); |
| 306 | if (lchan) |
| 307 | return lchan; |
| 308 | } |
| 309 | |
Holger Hans Peter Freyther | 3265b1a | 2009-10-27 10:42:53 +0100 | [diff] [blame] | 310 | return NULL; |
Harald Welte | aa60edb | 2009-08-09 18:52:33 +0200 | [diff] [blame] | 311 | } |