Introduce NACC support
A new nacc_fsm is introduced per MS object, with its partner priv
structure struct nacc_fsm_ctx, which exists and is available in the MS
object only during the duration of the NACC procedure.
The NACC context is created on an MS whenever a Pkt Cell Change
Notification is received on Uplink RLCMAC, which asks for neighbor
information of a given ARFCN+BSIC.
First, the target ARFCN+BSIC needs to be translated into a CGI-PS
(RAC+CI) address. That's done by asking the BSC through the Neighbour
Resolution Service available in osmo-bsc using the CTRL interface.
Once the CGI-PS of the target cell is known, PCU starts a RIM RAN-INFO
request against the SGSN (which will route the request as needed), and
wait for a response containing the SI bits from the target cell.
After the SI are received, the scheduler is instructed to eventually
poll a TBF for the MS originating the CCN, so that we can send the SI
encapsulated into multiple Packet Neighbor Cell Data messages on the
downlink.
One all the SI bits are sent, the scheduler is instructed to send a
Packet Cell Change Continue message.
Once the message above has been sent, the FSM autodestroys itself.
Caches are also introduced in this patch which allows for re-using
recently known translations ARFCN+BSIC -> CGI-PS and CGI-PS -> SI_INFO
respectively.
Change-Id: Id35f40d05f3e081f32fddbf1fa34cb338db452ca
diff --git a/src/gprs_bssgp_rim.c b/src/gprs_bssgp_rim.c
index cf43a8f..a191fff 100644
--- a/src/gprs_bssgp_rim.c
+++ b/src/gprs_bssgp_rim.c
@@ -26,6 +26,9 @@
#include "gprs_debug.h"
#include "gprs_pcu.h"
+#include "bts.h"
+#include "gprs_ms.h"
+#include "nacc_fsm.h"
#define LOGPRIM(nsei, level, fmt, args...) \
LOGP(DRIM, level, "(NSEI=%u) " fmt, nsei, ## args)
@@ -97,6 +100,65 @@
return false;
}
+static int handle_ran_info_response_nacc(const struct bssgp_ran_inf_app_cont_nacc *nacc, struct gprs_rlcmac_bts *bts)
+{
+ struct si_cache_value val;
+ struct si_cache_entry *entry;
+ struct llist_head *tmp;
+ int i;
+
+ LOGP(DRIM, LOGL_INFO, "Rx RAN-INFO cell=%s type=%sBCCH num_si=%d\n",
+ osmo_cgi_ps_name(&nacc->reprt_cell),
+ nacc->type_psi ? "P" : "", nacc->num_si);
+
+ val.type_psi = nacc->type_psi;
+ val.si_len = 0;
+ for (i = 0; i < nacc->num_si; i++) {
+ size_t len = val.type_psi ? BSSGP_RIM_PSI_LEN : BSSGP_RIM_SI_LEN;
+ memcpy(&val.si_buf[val.si_len], nacc->si[i], len);
+ val.si_len += len;
+ }
+ entry = si_cache_add(bts->pcu->si_cache, &nacc->reprt_cell, &val);
+
+ llist_for_each(tmp, bts_ms_list(bts)) {
+ struct GprsMs *ms = llist_entry(tmp, typeof(*ms), list);
+ if (!ms->nacc)
+ continue;
+ if (ms->nacc->fi->state != NACC_ST_WAIT_REQUEST_SI)
+ continue;
+ if (osmo_cgi_ps_cmp(&nacc->reprt_cell, &ms->nacc->cgi_ps) != 0)
+ continue;
+ osmo_fsm_inst_dispatch(ms->nacc->fi, NACC_EV_RX_SI, entry);
+ }
+ return 0;
+}
+
+static int handle_ran_info_response(const struct bssgp_ran_information_pdu *pdu, struct gprs_rlcmac_bts *bts)
+{
+ const struct bssgp_ran_inf_rim_cont *ran_info = &pdu->decoded.rim_cont;
+ char ri_src_str[64];
+
+ if (ran_info->app_err) {
+ LOGP(DRIM, LOGL_ERROR,
+ "%s Rx RAN-INFO with an app error! cause: %s\n",
+ bssgp_rim_ri_name_buf(ri_src_str, sizeof(ri_src_str), &pdu->routing_info_src),
+ bssgp_nacc_cause_str(ran_info->u.app_err_cont_nacc.nacc_cause));
+ return -1;
+ }
+
+ switch (pdu->decoded.rim_cont.app_id) {
+ case BSSGP_RAN_INF_APP_ID_NACC:
+ handle_ran_info_response_nacc(&ran_info->u.app_cont_nacc, bts);
+ break;
+ default:
+ LOGP(DRIM, LOGL_ERROR, "%s Rx RAN-INFO with unknown/wrong application ID %s received\n",
+ bssgp_rim_ri_name_buf(ri_src_str, sizeof(ri_src_str), &pdu->routing_info_src),
+ bssgp_ran_inf_app_id_str(pdu->decoded.rim_cont.app_id));
+ return -1;
+ }
+ return 0;
+}
+
int handle_rim(struct osmo_bssgp_prim *bp)
{
struct msgb *msg = bp->oph.msg;
@@ -151,8 +213,7 @@
LOGPRIM(nsei, LOGL_NOTICE, "Responding to RAN INFORMATION REQUEST not yet implemented!\n");
break;
case BSSGP_IE_RI_RIM_CONTAINER:
- LOGPRIM(nsei, LOGL_NOTICE, "Responding to RAN INFORMATION not yet implemented!\n");
- break;
+ return handle_ran_info_response(pdu, bts);
case BSSGP_IE_RI_APP_ERROR_RIM_CONT:
case BSSGP_IE_RI_ACK_RIM_CONTAINER:
case BSSGP_IE_RI_ERROR_RIM_COINTAINER: