minor api doc

Change-Id: I2291e34545844d3a6b82c0e9a3278bb422cc890c
---
M include/osmocom/upf/up_endpoint.h
M include/osmocom/upf/up_peer.h
M include/osmocom/upf/up_session.h
3 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/include/osmocom/upf/up_endpoint.h b/include/osmocom/upf/up_endpoint.h
index 3bb14ec..60b3927 100644
--- a/include/osmocom/upf/up_endpoint.h
+++ b/include/osmocom/upf/up_endpoint.h
@@ -35,6 +35,7 @@
 struct up_endpoint {
 	struct osmo_pfcp_endpoint *pfcp_ep;
 
+	/* list of struct up_peer. */
 	struct llist_head peers;
 
 	uint64_t next_seid_state;
diff --git a/include/osmocom/upf/up_peer.h b/include/osmocom/upf/up_peer.h
index 0c168cf..59c2b91 100644
--- a/include/osmocom/upf/up_peer.h
+++ b/include/osmocom/upf/up_peer.h
@@ -44,6 +44,7 @@
 	struct llist_head entry;
 
 	struct osmo_fsm_inst *fi;
+	/* backpointer */
 	struct up_endpoint *up_endpoint;
 
 	/* peer's remote address */
diff --git a/include/osmocom/upf/up_session.h b/include/osmocom/upf/up_session.h
index c459cd7..215a414 100644
--- a/include/osmocom/upf/up_session.h
+++ b/include/osmocom/upf/up_session.h
@@ -46,6 +46,7 @@
 	struct hlist_node node_by_cp_seid;
 
 	struct osmo_fsm_inst *fi;
+	/* backpointer */
 	struct up_peer *up_peer;
 
 	struct osmo_pfcp_ie_f_seid cp_f_seid;

