[osmo-pcu 3/3] bts: Split tbf_by_poll_fn into separate dl and ul functions

[Daniel Willmann]

rcv_control_dl_ack_nack is only meaningful for dl tbf while
rcv_control_ack can be sent in response to a dl or ul tbf. So
rcv_control_ack still needs to check for ul and dl tbfs.

Ticket: SYS#389
Sponsored-by: On-Waves ehf
---
 src/bts.cpp | 21 ++++++++++++++++-----
 src/bts.h   |  3 ++-
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/bts.cpp b/src/bts.cpp
index 52960cf..08baee0 100644
--- a/src/bts.cpp
+++ b/src/bts.cpp
@@ -248,20 +248,28 @@ gprs_rlcmac_tbf *BTS::tbf_by_tlli(uint32_t tlli, enum gprs_rlcmac_tbf_direction
 	return NULL;
 }
 
-gprs_rlcmac_tbf *BTS::tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts)
+gprs_rlcmac_tbf *BTS::dl_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts)
 {
 	struct gprs_rlcmac_tbf *tbf;
 
 	/* only one TBF can poll on specific TS/FN, because scheduler can only
 	 * schedule one downlink control block (with polling) at a FN per TS */
-	llist_for_each_entry(tbf, &m_bts.ul_tbfs, list) {
+	llist_for_each_entry(tbf, &m_bts.dl_tbfs, list) {
 		if (tbf->state_is_not(GPRS_RLCMAC_RELEASING)
 		 && tbf->poll_state == GPRS_RLCMAC_POLL_SCHED
 		 && tbf->poll_fn == fn && tbf->trx->trx_no == trx
 		 && tbf->control_ts == ts)
 			return tbf;
 	}
-	llist_for_each_entry(tbf, &m_bts.dl_tbfs, list) {
+	return NULL;
+}
+gprs_rlcmac_tbf *BTS::ul_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts)
+{
+	struct gprs_rlcmac_tbf *tbf;
+
+	/* only one TBF can poll on specific TS/FN, because scheduler can only
+	 * schedule one downlink control block (with polling) at a FN per TS */
+	llist_for_each_entry(tbf, &m_bts.ul_tbfs, list) {
 		if (tbf->state_is_not(GPRS_RLCMAC_RELEASING)
 		 && tbf->poll_state == GPRS_RLCMAC_POLL_SCHED
 		 && tbf->poll_fn == fn && tbf->trx->trx_no == trx
@@ -718,7 +726,10 @@ void gprs_rlcmac_pdch::rcv_control_ack(Packet_Control_Acknowledgement_t *packet,
 	uint32_t tlli = 0;
 
 	tlli = packet->TLLI;
-	tbf = bts()->tbf_by_poll_fn(fn, trx_no(), ts_no);
+	tbf = bts()->ul_tbf_by_poll_fn(fn, trx_no(), ts_no);
+	if (!tbf)
+		tbf = bts()->dl_tbf_by_poll_fn(fn, trx_no(), ts_no);
+
 	if (!tbf) {
 		LOGP(DRLCMAC, LOGL_NOTICE, "PACKET CONTROL ACK with "
 			"unknown FN=%u TLLI=0x%08x (TRX %d TS %d)\n",
@@ -804,7 +815,7 @@ void gprs_rlcmac_pdch::rcv_control_dl_ack_nack(Packet_Downlink_Ack_Nack_t *ack_n
 	int rc;
 
 	tfi = ack_nack->DOWNLINK_TFI;
-	tbf = bts()->tbf_by_poll_fn(fn, trx_no(), ts_no);
+	tbf = bts()->dl_tbf_by_poll_fn(fn, trx_no(), ts_no);
 	if (!tbf) {
 		LOGP(DRLCMAC, LOGL_NOTICE, "PACKET DOWNLINK ACK with "
 			"unknown FN=%u TFI=%d (TRX %d TS %d)\n",
diff --git a/src/bts.h b/src/bts.h
index a67f215..621bcba 100644
--- a/src/bts.h
+++ b/src/bts.h
@@ -194,7 +194,8 @@ public:
 
 	gprs_rlcmac_tbf *dl_tbf_by_tlli(uint32_t tlli);
 	gprs_rlcmac_tbf *ul_tbf_by_tlli(uint32_t tlli);
-	gprs_rlcmac_tbf *tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts);
+	gprs_rlcmac_tbf *dl_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts);
+	gprs_rlcmac_tbf *ul_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts);
 	gprs_rlcmac_tbf *dl_tbf_by_tfi(uint8_t tfi, uint8_t trx);
 	gprs_rlcmac_tbf *ul_tbf_by_tfi(uint8_t tfi, uint8_t trx);
 
-- 
1.8.4.2