consolidate ipa_unit infrastructure

Provide unified infrastructure for handling IPA units and modify
existing code to use it.

3 files changed, 245 insertions, 223 deletions

diff --git a/src/channel/abis/ipa_stream_client.c b/src/channel/abis/ipa_stream_client.c
index bb6a1ee..e6565c4 100644
--- a/src/channel/abis/ipa_stream_client.c
+++ b/src/channel/abis/ipa_stream_client.c
@@ -26,7 +26,7 @@
 static void *abis_ipa_cli_tall;
 
 struct chan_abis_ipa_cli {
-	struct ipaccess_unit *unit;
+	struct osmo_ipa_unit *unit;
 
 	struct osmo_stream_cli *oml;
 	struct osmo_stream_cli *rsl;
@@ -41,7 +41,7 @@ static int chan_abis_ipa_cli_create(struct osmo_chan *chan)
 {
 	struct chan_abis_ipa_cli *c = (struct chan_abis_ipa_cli *)chan->data;
 
-	c->unit = osmo_ipa_unit_alloc();
+	c->unit = osmo_ipa_unit_alloc(0);
 	if (c->unit == NULL)
 		goto err;
 
@@ -157,7 +157,7 @@ void osmo_abis_ipa_cli_set_rsl_port(struct osmo_chan *c, uint16_t port)
 	osmo_stream_cli_set_port(s->rsl, port);
 }
 
-void osmo_abis_ipa_cli_set_unit(struct osmo_chan *c, struct ipaccess_unit *unit)
+void osmo_abis_ipa_cli_set_unit(struct osmo_chan *c, struct osmo_ipa_unit *unit)
 {
 	struct chan_abis_ipa_cli *s = (struct chan_abis_ipa_cli *)&c->data;
 
@@ -174,7 +174,7 @@ void osmo_abis_ipa_cli_set_cb_signalmsg(struct osmo_chan *c,
 }
 
 static struct msgb *
-ipa_cli_id_resp(struct ipaccess_unit *dev, uint8_t *data, int len)
+ipa_cli_id_resp(struct osmo_ipa_unit *dev, uint8_t *data, int len)
 {
 	struct msgb *nmsg;
 	char str[64];
@@ -194,36 +194,28 @@ ipa_cli_id_resp(struct ipaccess_unit *dev, uint8_t *data, int len)
 		}
 		switch (data[1]) {
 		case IPAC_IDTAG_UNIT:
-			sprintf(str, "%u/%u/%u",
-				dev->site_id, dev->bts_id, dev->trx_id);
+			osmo_ipa_unit_snprintf(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_MACADDR:
-			sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
-				dev->mac_addr[0], dev->mac_addr[1],
-				dev->mac_addr[2], dev->mac_addr[3],
-				dev->mac_addr[4], dev->mac_addr[5]);
+			osmo_ipa_unit_snprintf_mac_addr(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_LOCATION1:
-			strcpy(str, dev->location1);
+			osmo_ipa_unit_snprintf_loc1(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_LOCATION2:
-			strcpy(str, dev->location2);
+			osmo_ipa_unit_snprintf_loc2(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_EQUIPVERS:
-			strcpy(str, dev->equipvers);
+			osmo_ipa_unit_snprintf_hwvers(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_SWVERSION:
-			strcpy(str, dev->swversion);
+			osmo_ipa_unit_snprintf_swvers(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_UNITNAME:
-			sprintf(str, "%s-%02x-%02x-%02x-%02x-%02x-%02x",
-				dev->unit_name,
-				dev->mac_addr[0], dev->mac_addr[1],
-				dev->mac_addr[2], dev->mac_addr[3],
-				dev->mac_addr[4], dev->mac_addr[5]);
+			osmo_ipa_unit_snprintf_name(str, sizeof(str), dev);
 			break;
 		case IPAC_IDTAG_SERNR:
-			strcpy(str, dev->serno);
+			osmo_ipa_unit_snprintf_serno(str, sizeof(str), dev);
 			break;
 		default:
 			LOGP(DLINP, LOGL_NOTICE,
diff --git a/src/channel/abis/ipa_stream_server.c b/src/channel/abis/ipa_stream_server.c
index 6524033..a47b0f6 100644
--- a/src/channel/abis/ipa_stream_server.c
+++ b/src/channel/abis/ipa_stream_server.c
@@ -14,6 +14,7 @@
 #include <osmocom/netif/channel.h>
 #include <osmocom/netif/stream.h>
 #include <osmocom/netif/ipa.h>
+#include <osmocom/netif/ipa_unit.h>
 
 #define CHAN_SIGN_OML	0
 #define CHAN_SIGN_RSL	1
@@ -28,41 +29,25 @@ static int oml_accept_cb(struct osmo_stream_srv_link *srv, int fd);
 static int rsl_accept_cb(struct osmo_stream_srv_link *srv, int fd);
 
 struct chan_abis_ipa_srv {
+	struct osmo_chan *chan;
 	struct osmo_stream_srv_link *oml;
 	struct osmo_stream_srv_link *rsl;
 
 	struct llist_head bts_list;
-	struct llist_head conn_list;
 
 	void (*signal_msg)(struct msgb *msg, int type);
 };
 
-struct ipa_unit {
-	struct llist_head	head;
-	uint16_t		site_id;
-	uint16_t		bts_id;
-};
+struct chan_abis_ipa_srv_conn {
+	struct chan_abis_ipa_srv *master;
 
-struct ipa {
-	struct llist_head		head;
-	struct ipa_unit 		*unit;
-	struct osmo_chan		*chan;
 	struct osmo_stream_srv	*oml;
 	struct osmo_stream_srv	*rsl;
 };
 
 static int chan_abis_ipa_srv_create(struct osmo_chan *chan)
 {
-	struct chan_abis_ipa_srv *c =
-		(struct chan_abis_ipa_srv *)chan->data;
-	struct ipa *ipa;
-
-	/* dummy connection. */
-	ipa = talloc_zero(chan->ctx, struct ipa);
-	if (ipa == NULL)
-		goto err;
-
-	ipa->chan = chan;
+	struct chan_abis_ipa_srv *c = (struct chan_abis_ipa_srv *)chan->data;
 
 	c->oml = osmo_stream_srv_link_create(abis_ipa_srv_tall);
 	if (c->oml == NULL)
@@ -72,7 +57,7 @@ static int chan_abis_ipa_srv_create(struct osmo_chan *chan)
 	osmo_stream_srv_link_set_addr(c->oml, "0.0.0.0");
 	osmo_stream_srv_link_set_port(c->oml, IPA_TCP_PORT_OML);
 	osmo_stream_srv_link_set_accept_cb(c->oml, oml_accept_cb);
-	osmo_stream_srv_link_set_data(c->oml, ipa);
+	osmo_stream_srv_link_set_data(c->oml, c);
 
 	c->rsl = osmo_stream_srv_link_create(abis_ipa_srv_tall);
 	if (c->rsl == NULL)
@@ -82,36 +67,28 @@ static int chan_abis_ipa_srv_create(struct osmo_chan *chan)
 	osmo_stream_srv_link_set_addr(c->rsl, "0.0.0.0");
 	osmo_stream_srv_link_set_port(c->rsl, IPA_TCP_PORT_RSL);
 	osmo_stream_srv_link_set_accept_cb(c->rsl, rsl_accept_cb);
-	osmo_stream_srv_link_set_data(c->rsl, ipa);
+	osmo_stream_srv_link_set_data(c->rsl, c);
 
 	INIT_LLIST_HEAD(&c->bts_list);
-	INIT_LLIST_HEAD(&c->conn_list);
 
 	return 0;
 err_rsl:
 	osmo_stream_srv_link_destroy(c->oml);
 err_oml:
-	talloc_free(ipa);
-err:
 	return -1;
 }
 
 static void chan_abis_ipa_srv_destroy(struct osmo_chan *chan)
 {
-	struct chan_abis_ipa_srv *c =
-		(struct chan_abis_ipa_srv *)chan->data;
-	struct ipa *ipa =
-		osmo_stream_srv_link_get_data(c->oml);
-
-	talloc_free(ipa);
-	talloc_free(c->rsl);
-	talloc_free(c->oml);
+	struct chan_abis_ipa_srv *c = (struct chan_abis_ipa_srv *)chan->data;
+
+	osmo_stream_srv_link_destroy(c->rsl);
+	osmo_stream_srv_link_destroy(c->oml);
 }
 
 static int chan_abis_ipa_srv_open(struct osmo_chan *chan)
 {
-	struct chan_abis_ipa_srv *c =
-		(struct chan_abis_ipa_srv *)chan->data;
+	struct chan_abis_ipa_srv *c = (struct chan_abis_ipa_srv *)chan->data;
 	struct osmo_fd *ofd;
 	int ret, on = 1;
 
@@ -143,8 +120,7 @@ err:
 
 static void chan_abis_ipa_srv_close(struct osmo_chan *chan)
 {
-	struct chan_abis_ipa_srv *c =
-		(struct chan_abis_ipa_srv *)chan->data;
+	struct chan_abis_ipa_srv *c = (struct chan_abis_ipa_srv *)chan->data;
 
 	osmo_stream_srv_link_close(c->oml);
 	osmo_stream_srv_link_close(c->rsl);
@@ -156,63 +132,72 @@ static int chan_abis_ipa_srv_enqueue(struct osmo_chan *c, struct msgb *msg)
 	return 0;
 }
 
-void
-osmo_abis_ipa_srv_set_oml_addr(struct osmo_chan *c, const char *addr)
+void osmo_abis_ipa_srv_set_oml_addr(struct osmo_chan *c, const char *addr)
 {
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)&c->data;
+	struct chan_abis_ipa_srv *s = (struct chan_abis_ipa_srv *)&c->data;
 
 	osmo_stream_srv_link_set_addr(s->oml, addr);
 }
 
-void
-osmo_abis_ipa_srv_set_oml_port(struct osmo_chan *c, uint16_t port)
+void osmo_abis_ipa_srv_set_oml_port(struct osmo_chan *c, uint16_t port)
 {
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)&c->data;
+	struct chan_abis_ipa_srv *s = (struct chan_abis_ipa_srv *)&c->data;
 
 	osmo_stream_srv_link_set_port(s->oml, port);
 }
 
-void
-osmo_abis_ipa_srv_set_rsl_addr(struct osmo_chan *c, const char *addr)
+void osmo_abis_ipa_srv_set_rsl_addr(struct osmo_chan *c, const char *addr)
 {
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)&c->data;
+	struct chan_abis_ipa_srv *s = (struct chan_abis_ipa_srv *)&c->data;
 
 	osmo_stream_srv_link_set_addr(s->rsl, addr);
 }
 
-void
-osmo_abis_ipa_srv_set_rsl_port(struct osmo_chan *c, uint16_t port)
+void osmo_abis_ipa_srv_set_rsl_port(struct osmo_chan *c, uint16_t port)
 {
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)&c->data;
+	struct chan_abis_ipa_srv *s = (struct chan_abis_ipa_srv *)&c->data;
 
 	osmo_stream_srv_link_set_port(s->rsl, port);
 }
 
-void
-osmo_abis_ipa_srv_set_cb_signalmsg(struct osmo_chan *c,
+void osmo_abis_ipa_srv_set_cb_signalmsg(struct osmo_chan *c,
 	void (*signal_msg)(struct msgb *msg, int type))
 {
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)&c->data;
+	struct chan_abis_ipa_srv *s = (struct chan_abis_ipa_srv *)&c->data;
 
 	s->signal_msg = signal_msg;
 }
 
+int
+osmo_abis_ipa_unit_add(struct osmo_chan *c, uint16_t site_id, uint16_t bts_id)
+{
+	struct osmo_ipa_unit *unit;
+	struct chan_abis_ipa_srv *s = (struct chan_abis_ipa_srv *)&c->data;
+	struct chan_abis_ipa_srv_conn *inst;
+
+	unit = osmo_ipa_unit_alloc(sizeof(struct chan_abis_ipa_srv_conn));
+	if (unit == NULL)
+		return -1;
+
+	osmo_ipa_unit_set_site_id(unit, site_id);
+	osmo_ipa_unit_set_bts_id(unit, bts_id);
+	osmo_ipa_unit_add(&s->bts_list, unit);
+
+	inst = osmo_ipa_unit_get_data(unit);
+	inst->master = s;
+
+	return 0;
+}
+
 static int oml_read_cb(struct osmo_stream_srv *conn);
 
 static int oml_accept_cb(struct osmo_stream_srv_link *srv, int fd)
 {
 	struct osmo_stream_srv *conn;
-	struct ipa *ipa = osmo_stream_srv_link_get_data(srv);
 	struct osmo_fd *ofd;
 
 	conn = osmo_stream_srv_create(abis_ipa_srv_tall,
-					      srv, fd,
-					      oml_read_cb, NULL, ipa);
+				      srv, fd, oml_read_cb, NULL, NULL);
 	if (conn == NULL) {
 		LOGP(DLINP, LOGL_ERROR, "error while creating connection\n");
 		return -1;
@@ -231,11 +216,10 @@ static int rsl_read_cb(struct osmo_stream_srv *conn);
 static int rsl_accept_cb(struct osmo_stream_srv_link *srv, int fd)
 {
 	struct osmo_stream_srv *conn;
-	struct ipa *ipa = osmo_stream_srv_link_get_data(srv);
 	struct osmo_fd *ofd;
 
 	conn = osmo_stream_srv_create(abis_ipa_srv_tall, srv, fd,
-				      rsl_read_cb, NULL, ipa);
+				      rsl_read_cb, NULL, NULL);
 	if (conn == NULL) {
 		LOGP(DLINP, LOGL_ERROR, "error while creating connection\n");
 		return -1;
@@ -249,103 +233,25 @@ static int rsl_accept_cb(struct osmo_stream_srv_link *srv, int fd)
 	return 0;
 }
 
-static struct ipa_unit *
-osmo_abis_ipa_unit_find(struct osmo_chan *c, uint16_t site_id, uint16_t bts_id)
-{
-	struct ipa_unit *unit;
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)c->data;
-
-	llist_for_each_entry(unit, &s->bts_list, head) {
-		if (unit->site_id == site_id &&
-		    unit->bts_id == bts_id)
-			return unit;
-	}
-	return NULL;
-}
-
-int
-osmo_abis_ipa_unit_add(struct osmo_chan *c,
-			    uint16_t site_id, uint16_t bts_id)
-{
-	struct ipa_unit *unit;
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)c->data;
-
-	unit = talloc_zero(c->ctx, struct ipa_unit);
-	if (unit == NULL)
-		return -1;
-
-	unit->site_id = site_id;
-	unit->bts_id = bts_id;
-	llist_add(&unit->head, &s->bts_list);
-
-	return 0;
-}
-
-static struct ipa *
-osmo_abis_ipa_alloc(struct ipa_unit *unit, struct osmo_chan *chan)
-{
-	struct ipa *ipa;
-
-	ipa = talloc_zero(chan->ctx, struct ipa);
-	if (ipa == NULL)
-		return NULL;
-
-	ipa->unit = unit;
-	ipa->chan = chan;
-
-	return ipa;
-}
-
-static struct ipa *
-osmo_abis_ipa_add(struct ipa_unit *unit, struct osmo_chan *chan)
+static void abis_ipa_put(struct osmo_ipa_unit *unit)
 {
-	struct ipa *ipa;
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)chan->data;
+	struct chan_abis_ipa_srv_conn *inst = osmo_ipa_unit_get_data(unit);
 
-	ipa = osmo_abis_ipa_alloc(unit, chan);
-	if (ipa == NULL)
-		return NULL;
-
-	llist_add(&ipa->head, &s->conn_list);
-
-	return ipa;
-}
-
-static struct ipa *
-osmo_abis_ipa_find(struct ipa_unit *unit, struct osmo_chan *chan)
-{
-	struct ipa *ipa;
-	struct chan_abis_ipa_srv *s =
-		(struct chan_abis_ipa_srv *)chan->data;
-
-	llist_for_each_entry(ipa, &s->conn_list, head) {
-		if (ipa->unit->site_id == unit->site_id &&
-		    ipa->unit->bts_id == unit->bts_id) {
-			return ipa;
-		}
-	}
-	return NULL;
-}
-
-static void abis_ipa_put(struct ipa *ipa)
-{
-	llist_del(&ipa->head);
-	osmo_stream_srv_destroy(ipa->oml);
-	osmo_stream_srv_destroy(ipa->rsl);
-	talloc_free(ipa);
+	osmo_stream_srv_destroy(inst->oml);
+	osmo_stream_srv_destroy(inst->rsl);
+	inst->oml = NULL;
+	inst->rsl = NULL;
 }
 
 static int
-abis_ipa_srv_rcvmsg(struct osmo_chan *c,
-		       struct osmo_stream_srv *conn,
-		       struct msgb *msg, int type)
+abis_ipa_srv_rcvmsg(struct osmo_stream_srv *conn, struct msgb *msg, int type)
 {
 	struct tlv_parsed tlvp;
 	uint8_t msg_type = *(msg->l2h);
 	struct osmo_fd *ofd = osmo_stream_srv_get_ofd(conn);
+	struct osmo_stream_srv_link *link = osmo_stream_srv_get_master(conn);
+	struct chan_abis_ipa_srv *s = osmo_stream_srv_link_get_data(link);
+	struct chan_abis_ipa_srv_conn *inst;
 	char *unitid;
 	int len, ret;
 
@@ -354,15 +260,13 @@ abis_ipa_srv_rcvmsg(struct osmo_chan *c,
 		return 0;
 
 	if (msg_type == IPAC_MSGT_ID_RESP) {
-		struct ipa_unit *unit;
-		struct ipa *ipa;
+		struct osmo_ipa_unit *unit;
 		struct ipaccess_unit unit_data;
 
-		DEBUGP(DLMI, "ID_RESP\n");
+		DEBUGP(DLINP, "ID_RESP\n");
 		/* parse tags, search for Unit ID */
 		ret = osmo_ipa_idtag_parse(&tlvp, (uint8_t *)msg->l2h + 2,
 						msgb_l2len(msg)-2);
-		DEBUGP(DLMI, "\n");
 		if (ret < 0) {
 			LOGP(DLINP, LOGL_ERROR, "IPA response message "
 				"with malformed TLVs\n");
@@ -387,8 +291,9 @@ abis_ipa_srv_rcvmsg(struct osmo_chan *c,
 		unitid[len - 1] = '\0';
 		osmo_ipa_parse_unitid(unitid, &unit_data);
 
-		unit = osmo_abis_ipa_unit_find(c, unit_data.site_id,
+		unit = osmo_ipa_unit_find(&s->bts_list, unit_data.site_id,
 					  unit_data.bts_id);
+
 		if (unit == NULL) {
 			LOGP(DLINP, LOGL_ERROR, "Unable to find BTS "
 				"configuration for %u/%u/%u, disconnecting\n",
@@ -400,36 +305,29 @@ abis_ipa_srv_rcvmsg(struct osmo_chan *c,
 			unit_data.site_id, unit_data.bts_id,
 			unit_data.trx_id);
 
-		ipa = osmo_abis_ipa_find(unit, c);
-		if (ipa == NULL) {
-			ipa = osmo_abis_ipa_add(unit, c);
-			if (ipa == NULL) {
-				LOGP(DLINP, LOGL_ERROR, "OOM\n");
-				return 0;
-			}
-			osmo_stream_srv_set_data(conn, ipa);
-		}
+		inst = osmo_ipa_unit_get_data(unit);
 
 		if (type == CHAN_SIGN_OML) {
-			if (ipa->oml) {
+			if (inst->oml) {
 				/* link already exists, kill it. */
-				osmo_stream_srv_destroy(ipa->oml);
+				osmo_stream_srv_destroy(inst->oml);
 				return 0;
 			}
-			ipa->oml = conn;
+			inst->oml = conn;
 		} else if (type == CHAN_SIGN_RSL) {
-			if (!ipa->oml) {
+			if (!inst->oml) {
 				/* no OML link? Restart from scratch. */
-				abis_ipa_put(ipa);
+				abis_ipa_put(unit);
 				return 0;
 			}
-			if (ipa->rsl) {
+			if (inst->rsl) {
 				/* RSL link already exists, kill it. */
-				osmo_stream_srv_destroy(ipa->rsl);
+				osmo_stream_srv_destroy(inst->rsl);
 				return 0;
 			}
-			ipa->rsl = conn;
+			inst->rsl = conn;
 		}
+		osmo_stream_srv_set_data(conn, unit);
 		ret = 0;
 	} else {
 		LOGP(DLINP, LOGL_ERROR, "Unknown IPA message type\n");
@@ -444,8 +342,8 @@ static int read_cb(struct osmo_stream_srv *conn, int type)
 	int ret;
 	struct msgb *msg;
 	struct osmo_fd *ofd = osmo_stream_srv_get_ofd(conn);
-	struct ipa *ipa = osmo_stream_srv_get_data(conn);
-	struct chan_abis_ipa_srv *s;
+	struct osmo_ipa_unit *unit = osmo_stream_srv_get_data(conn);
+	struct chan_abis_ipa_srv_conn *inst;
 	struct ipa_head *hh;
 
 	LOGP(DLINP, LOGL_DEBUG, "received message from stream\n");
@@ -459,42 +357,41 @@ static int read_cb(struct osmo_stream_srv *conn, int type)
 	if (ret < 0) {
 		LOGP(DLINP, LOGL_ERROR, "cannot receive message\n");
 		msgb_free(msg);
-		/* not the dummy connection, release it. */
-		if (ipa->unit != NULL)
-			abis_ipa_put(ipa);
+		if (unit != NULL)
+			abis_ipa_put(unit);
 		return 0;
 	} else if (ret == 0) {
 		/* link has vanished, dead socket. */
 		LOGP(DLINP, LOGL_ERROR, "closed connection\n");
 		msgb_free(msg);
-		if (ipa->unit != NULL)
-			abis_ipa_put(ipa);
+		if (unit != NULL)
+			abis_ipa_put(unit);
 
-		/* ... the stream socket releases this connection for us */
 		return 0;
 	}
+	/* XXX: missing IPA message validation */
 
 	hh = (struct ipa_head *) msg->data;
 	if (hh->proto == IPAC_PROTO_IPACCESS) {
-		abis_ipa_srv_rcvmsg(ipa->chan, conn, msg, type);
+		abis_ipa_srv_rcvmsg(conn, msg, type);
 		msgb_free(msg);
 		return -EIO;
 	}
 
-	ipa = osmo_stream_srv_get_data(conn);
-	if (ipa == NULL) {
-		LOGP(DLINP, LOGL_ERROR, "no matching signalling link\n");
-		msgb_free(msg);
+	if (unit == NULL) {
+		LOGP(DLINP, LOGL_ERROR, "no IPA unit associated to this "
+					"connection\n");
 		return -EIO;
 	}
+	inst = osmo_ipa_unit_get_data(unit);
+
 	if (hh->proto != IPAC_PROTO_OML && hh->proto != IPAC_PROTO_RSL) {
 		LOGP(DLINP, LOGL_ERROR, "wrong protocol\n");
 		return -EIO;
 	}
-	msg->dst = ipa;
+	msg->dst = conn;
 
-	s = (struct chan_abis_ipa_srv *)ipa->chan->data;
-	s->signal_msg(msg, type);
+	inst->master->signal_msg(msg, type);
 
 	return 0;
 }
diff --git a/src/ipa_unit.c b/src/ipa_unit.c
index ccf8841..a631921 100644
--- a/src/ipa_unit.c
+++ b/src/ipa_unit.c
@@ -1,9 +1,12 @@
 #include <osmocom/core/talloc.h>
+#include <osmocom/core/linuxlist.h>
 
 #include <stdint.h>
 #include <string.h>
 
-struct ipaccess_unit {
+struct osmo_ipa_unit {
+	struct llist_head head;
+
 	uint16_t	site_id;
 	uint16_t	bts_id;
 	uint16_t	trx_id;
@@ -14,13 +17,15 @@ struct ipaccess_unit {
 	char		*location1;
 	char		*location2;
 	char		*serno;
+
+	uint8_t		data[0];
 };
 
-struct ipaccess_unit *osmo_ipa_unit_alloc()
+struct osmo_ipa_unit *osmo_ipa_unit_alloc(size_t datalen)
 {
-	struct ipaccess_unit *unit;
+	struct osmo_ipa_unit *unit;
 
-	unit = talloc_zero(NULL, struct ipaccess_unit);
+	unit = talloc_zero_size(NULL, sizeof(struct osmo_ipa_unit) + datalen);
 	if (unit == NULL)
 		return NULL;
 
@@ -34,7 +39,7 @@ struct ipaccess_unit *osmo_ipa_unit_alloc()
 	return unit;
 }
 
-void osmo_ipa_unit_free(struct ipaccess_unit *unit)
+void osmo_ipa_unit_free(struct osmo_ipa_unit *unit)
 {
 	if (unit->name)
 		free(unit->name);
@@ -52,22 +57,27 @@ void osmo_ipa_unit_free(struct ipaccess_unit *unit)
 	talloc_free(unit);
 }
 
-void osmo_ipa_unit_set_site_id(struct ipaccess_unit *unit, uint16_t site_id)
+void *osmo_ipa_unit_get_data(struct osmo_ipa_unit *unit)
+{
+	return unit->data;
+}
+
+void osmo_ipa_unit_set_site_id(struct osmo_ipa_unit *unit, uint16_t site_id)
 {
 	unit->site_id = site_id;
 }
 
-void osmo_ipa_unit_set_bts_id(struct ipaccess_unit *unit, uint16_t bts_id)
+void osmo_ipa_unit_set_bts_id(struct osmo_ipa_unit *unit, uint16_t bts_id)
 {
 	unit->bts_id = bts_id;
 }
 
-void osmo_ipa_unit_set_trx_id(struct ipaccess_unit *unit, uint16_t trx_id)
+void osmo_ipa_unit_set_trx_id(struct osmo_ipa_unit *unit, uint16_t trx_id)
 {
 	unit->trx_id = trx_id;
 }
 
-void osmo_ipa_unit_set_unit_name(struct ipaccess_unit *unit, const char *name)
+void osmo_ipa_unit_set_unit_name(struct osmo_ipa_unit *unit, const char *name)
 {
 	if (unit->name)
 		free(unit->name);
@@ -75,7 +85,7 @@ void osmo_ipa_unit_set_unit_name(struct ipaccess_unit *unit, const char *name)
 	unit->name = strdup(name);
 }
 
-void osmo_ipa_unit_set_unit_hwvers(struct ipaccess_unit *unit, const char *vers)
+void osmo_ipa_unit_set_unit_hwvers(struct osmo_ipa_unit *unit, const char *vers)
 {
 	if (unit->hwvers)
 		free(unit->hwvers);
@@ -83,7 +93,7 @@ void osmo_ipa_unit_set_unit_hwvers(struct ipaccess_unit *unit, const char *vers)
 	unit->hwvers = strdup(vers);
 }
 
-void osmo_ipa_unit_set_unit_swvers(struct ipaccess_unit *unit, const char *vers)
+void osmo_ipa_unit_set_unit_swvers(struct osmo_ipa_unit *unit, const char *vers)
 {
 	if (unit->swvers)
 		free(unit->swvers);
@@ -91,12 +101,12 @@ void osmo_ipa_unit_set_unit_swvers(struct ipaccess_unit *unit, const char *vers)
 	unit->swvers = strdup(vers);
 }
 
-void osmo_ipa_unit_set_unit_mac_addr(struct ipaccess_unit *unit, uint8_t *addr)
+void osmo_ipa_unit_set_unit_mac_addr(struct osmo_ipa_unit *unit, uint8_t *addr)
 {
 	memcpy(unit->mac_addr, addr, sizeof(unit->mac_addr));
 }
 
-void osmo_ipa_unit_set_unit_loc1(struct ipaccess_unit *unit, const char *loc)
+void osmo_ipa_unit_set_unit_location1(struct osmo_ipa_unit *unit, const char *loc)
 {
 	if (unit->location1)
 		free(unit->location1);
@@ -104,7 +114,7 @@ void osmo_ipa_unit_set_unit_loc1(struct ipaccess_unit *unit, const char *loc)
 	unit->location1 = strdup(loc);
 }
 
-void osmo_ipa_unit_set_unit_loc2(struct ipaccess_unit *unit, const char *loc)
+void osmo_ipa_unit_set_unit_location2(struct osmo_ipa_unit *unit, const char *loc)
 {
 	if (unit->location2)
 		free(unit->location2);
@@ -112,7 +122,130 @@ void osmo_ipa_unit_set_unit_loc2(struct ipaccess_unit *unit, const char *loc)
 	unit->location2 = strdup(loc);
 }
 
-void osmo_ipa_unit_set_unit_serno(struct ipaccess_unit *unit, const char *serno)
+void osmo_ipa_unit_set_unit_serno(struct osmo_ipa_unit *unit, const char *serno)
 {
 	unit->serno = strdup(serno);
 }
+
+uint16_t osmo_ipa_unit_get_site_id(struct osmo_ipa_unit *unit)
+{
+	return unit->site_id;
+}
+
+uint16_t osmo_ipa_unit_get_bts_id(struct osmo_ipa_unit *unit)
+{
+	return unit->bts_id;
+}
+
+uint16_t osmo_ipa_unit_get_trx_id(struct osmo_ipa_unit *unit)
+{
+	return unit->trx_id;
+}
+
+const char *osmo_ipa_unit_get_unit_name(struct osmo_ipa_unit *unit)
+{
+	return unit->name;
+}
+
+const char *osmo_ipa_unit_get_unit_hwvers(struct osmo_ipa_unit *unit)
+{
+	return unit->hwvers;
+}
+
+const char *osmo_ipa_unit_get_unit_swvers(struct osmo_ipa_unit *unit)
+{
+	return unit->swvers;
+}
+
+uint8_t *osmo_ipa_unit_get_unit_mac_addr(struct osmo_ipa_unit *unit)
+{
+	return unit->mac_addr;
+}
+
+const char *osmo_ipa_unit_get_unit_location1(struct osmo_ipa_unit *unit)
+{
+	return unit->location1;
+}
+
+const char *osmo_ipa_unit_get_unit_location2(struct osmo_ipa_unit *unit)
+{
+	return unit->location2;
+}
+
+const char *osmo_ipa_unit_get_unit_serno(struct osmo_ipa_unit *unit)
+{
+	return unit->serno;
+}
+
+struct osmo_ipa_unit *
+osmo_ipa_unit_find(struct llist_head *list, uint16_t site_id, uint16_t bts_id)
+{
+	struct osmo_ipa_unit *unit;
+
+	llist_for_each_entry(unit, list, head) {
+		if (unit->site_id == site_id &&
+		    unit->bts_id == bts_id)
+			return unit;
+	}
+	return NULL;
+}
+
+void osmo_ipa_unit_add(struct llist_head *list, struct osmo_ipa_unit *unit)
+{
+	llist_add(&unit->head, list);
+}
+
+int osmo_ipa_unit_snprintf(char *buf, size_t size, struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%u/%u/%u",
+			unit->site_id, unit->bts_id, unit->trx_id);
+}
+
+int osmo_ipa_unit_snprintf_mac_addr(char *buf, size_t size,
+				    struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%02x:%02x:%02x:%02x:%02x:%02x",
+			unit->mac_addr[0], unit->mac_addr[1],
+			unit->mac_addr[2], unit->mac_addr[3],
+			unit->mac_addr[4], unit->mac_addr[5]);
+}
+
+int osmo_ipa_unit_snprintf_name(char *buf, size_t size,
+				struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%s-%02x-%02x-%02x-%02x-%02x-%02x",
+			unit->name,
+			unit->mac_addr[0], unit->mac_addr[1],
+			unit->mac_addr[2], unit->mac_addr[3],
+			unit->mac_addr[4], unit->mac_addr[5]);
+}
+
+int osmo_ipa_unit_snprintf_loc1(char *buf, size_t size,
+				struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%s", unit->location1);
+}
+
+int osmo_ipa_unit_snprintf_loc2(char *buf, size_t size,
+				struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%s", unit->location2);
+}
+
+int osmo_ipa_unit_snprintf_hwvers(char *buf, size_t size,
+				  struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%s", unit->hwvers);
+}
+
+int osmo_ipa_unit_snprintf_swvers(char *buf, size_t size,
+				  struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%s", unit->hwvers);
+}
+
+int osmo_ipa_unit_snprintf_serno(char *buf, size_t size,
+				 struct osmo_ipa_unit *unit)
+{
+	return snprintf(buf, size, "%s", unit->serno);
+}