| /* GSM BSC Radio Link Layer API |
| * 3GPP TS 08.58 version 8.6.0 Release 1999 / ETSI TS 100 596 V8.6.0 */ |
| |
| /* (C) 2009 by Harald Welte <laforge@gnumonks.org> |
| * |
| * All Rights Reserved |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Affero General Public License as published by |
| * the Free Software Foundation; either version 3 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 Affero General Public License for more details. |
| * |
| * You should have received a copy of the GNU Affero General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| #include <errno.h> |
| |
| #include <openbsc/debug.h> |
| #include <osmocom/core/talloc.h> |
| #include <osmocom/core/timer.h> |
| #include <osmocom/core/linuxlist.h> |
| #include <openbsc/bsc_rll.h> |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/chan_alloc.h> |
| #include <openbsc/abis_rsl.h> |
| #include <openbsc/signal.h> |
| |
| struct bsc_rll_req { |
| struct llist_head list; |
| struct osmo_timer_list timer; |
| |
| struct gsm_lchan *lchan; |
| uint8_t link_id; |
| |
| void (*cb)(struct gsm_lchan *lchan, uint8_t link_id, |
| void *data, enum bsc_rllr_ind); |
| void *data; |
| }; |
| |
| /* we only compare C1, C2 and SAPI */ |
| #define LINKID_MASK 0xC7 |
| |
| static LLIST_HEAD(bsc_rll_reqs); |
| |
| static void complete_rllr(struct bsc_rll_req *rllr, enum bsc_rllr_ind type) |
| { |
| llist_del(&rllr->list); |
| rllr->cb(rllr->lchan, rllr->link_id, rllr->data, type); |
| talloc_free(rllr); |
| } |
| |
| static void timer_cb(void *_rllr) |
| { |
| struct bsc_rll_req *rllr = _rllr; |
| |
| complete_rllr(rllr, BSC_RLLR_IND_TIMEOUT); |
| } |
| |
| /* establish a RLL connection with given SAPI / priority */ |
| int rll_establish(struct gsm_lchan *lchan, uint8_t sapi, |
| void (*cb)(struct gsm_lchan *, uint8_t, void *, |
| enum bsc_rllr_ind), |
| void *data) |
| { |
| struct bsc_rll_req *rllr = talloc_zero(tall_bsc_ctx, struct bsc_rll_req); |
| uint8_t link_id; |
| if (!rllr) |
| return -ENOMEM; |
| |
| link_id = sapi; |
| |
| /* If we are a TCH and not in signalling mode, we need to |
| * indicate that the new RLL connection is to be made on the SACCH */ |
| if ((lchan->type == GSM_LCHAN_TCH_F || |
| lchan->type == GSM_LCHAN_TCH_H) && sapi != 0) |
| link_id |= 0x40; |
| |
| rllr->lchan = lchan; |
| rllr->link_id = link_id; |
| rllr->cb = cb; |
| rllr->data = data; |
| |
| llist_add(&rllr->list, &bsc_rll_reqs); |
| |
| rllr->timer.cb = &timer_cb; |
| rllr->timer.data = rllr; |
| |
| osmo_timer_schedule(&rllr->timer, 7, 0); |
| |
| /* send the RSL RLL ESTablish REQuest */ |
| return rsl_establish_request(rllr->lchan, rllr->link_id); |
| } |
| |
| /* Called from RSL code in case we have received an indication regarding |
| * any RLL link */ |
| void rll_indication(struct gsm_lchan *lchan, uint8_t link_id, uint8_t type) |
| { |
| struct bsc_rll_req *rllr, *rllr2; |
| |
| llist_for_each_entry_safe(rllr, rllr2, &bsc_rll_reqs, list) { |
| if (rllr->lchan == lchan && |
| (rllr->link_id & LINKID_MASK) == (link_id & LINKID_MASK)) { |
| osmo_timer_del(&rllr->timer); |
| complete_rllr(rllr, type); |
| return; |
| } |
| } |
| } |
| |
| static int rll_lchan_signal(unsigned int subsys, unsigned int signal, |
| void *handler_data, void *signal_data) |
| { |
| struct challoc_signal_data *challoc; |
| struct bsc_rll_req *rllr, *rllr2; |
| |
| if (subsys != SS_CHALLOC || signal != S_CHALLOC_FREED) |
| return 0; |
| |
| challoc = (struct challoc_signal_data *) signal_data; |
| |
| llist_for_each_entry_safe(rllr, rllr2, &bsc_rll_reqs, list) { |
| if (rllr->lchan == challoc->lchan) { |
| osmo_timer_del(&rllr->timer); |
| complete_rllr(rllr, BSC_RLLR_IND_ERR_IND); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static __attribute__((constructor)) void on_dso_load_rll(void) |
| { |
| osmo_signal_register_handler(SS_CHALLOC, rll_lchan_signal, NULL); |
| } |