[PATCH 09/12] udp_flow: Take pif and port as explicit parameters to udp_flow_from_sock()

[David Gibson <david@gibson.dropbear.id.au>]

Currently udp_flow_from_sock() is only used when receiving a datagram
from a "listening" socket.  It takes the listening socket's epoll
reference to get the interface and port on which the datagram arrived.

We have some upcoming cases where we want to use this in different
contexts, so make it take the pif and port as direct parameters instead.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 udp.c      |  4 +++-
 udp_flow.c | 15 +++++++--------
 udp_flow.h |  2 +-
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/udp.c b/udp.c
index f6de2924..dbb33f2a 100644
--- a/udp.c
+++ b/udp.c
@@ -728,7 +728,9 @@ static void udp_listen_sock_data(const struct ctx *c, union epoll_ref ref,
 	union sockaddr_inany src;
 
 	while (udp_peek_addr(ref.fd, &src) == 0) {
-		flow_sidx_t tosidx = udp_flow_from_sock(c, ref, &src, now);
+		flow_sidx_t tosidx = udp_flow_from_sock(c, ref.udp.pif,
+							ref.udp.port, &src,
+							now);
 		uint8_t topif = pif_at_sidx(tosidx);
 
 		if (pif_is_socket(topif)) {
diff --git a/udp_flow.c b/udp_flow.c
index d50bddb2..b95c3176 100644
--- a/udp_flow.c
+++ b/udp_flow.c
@@ -160,8 +160,10 @@ cancel:
 }
 
 /**
- * udp_flow_from_sock() - Find or create UDP flow for "listening" socket
+ * udp_flow_from_sock() - Find or create UDP flow for incoming datagram
  * @c:		Execution context
+ * @pif:	Interface the datagram is arriving from
+ * @port:	Our (local) port number to which the datagram is arriving
  * @ref:	epoll reference of the receiving socket
  * @s_in:	Source socket address, filled in by recvmmsg()
  * @now:	Timestamp
@@ -171,7 +173,7 @@ cancel:
  * Return: sidx for the destination side of the flow for this packet, or
  *         FLOW_SIDX_NONE if we couldn't find or create a flow.
  */
-flow_sidx_t udp_flow_from_sock(const struct ctx *c, union epoll_ref ref,
+flow_sidx_t udp_flow_from_sock(const struct ctx *c, uint8_t pif, in_port_t port,
 			       const union sockaddr_inany *s_in,
 			       const struct timespec *now)
 {
@@ -180,9 +182,7 @@ flow_sidx_t udp_flow_from_sock(const struct ctx *c, union epoll_ref ref,
 	union flow *flow;
 	flow_sidx_t sidx;
 
-	ASSERT(ref.type == EPOLL_TYPE_UDP_LISTEN);
-
-	sidx = flow_lookup_sa(c, IPPROTO_UDP, ref.udp.pif, s_in, ref.udp.port);
+	sidx = flow_lookup_sa(c, IPPROTO_UDP, pif, s_in, port);
 	if ((uflow = udp_at_sidx(sidx))) {
 		uflow->ts = now->tv_sec;
 		return flow_sidx_opposite(sidx);
@@ -192,12 +192,11 @@ flow_sidx_t udp_flow_from_sock(const struct ctx *c, union epoll_ref ref,
 		char sastr[SOCKADDR_STRLEN];
 
 		debug("Couldn't allocate flow for UDP datagram from %s %s",
-		      pif_name(ref.udp.pif),
-		      sockaddr_ntop(s_in, sastr, sizeof(sastr)));
+		      pif_name(pif), sockaddr_ntop(s_in, sastr, sizeof(sastr)));
 		return FLOW_SIDX_NONE;
 	}
 
-	ini = flow_initiate_sa(flow, ref.udp.pif, s_in, ref.udp.port);
+	ini = flow_initiate_sa(flow, pif, s_in, port);
 
 	if (!inany_is_unicast(&ini->eaddr) ||
 	    ini->eport == 0 || ini->oport == 0) {
diff --git a/udp_flow.h b/udp_flow.h
index 9a1b059c..d4e4c8b9 100644
--- a/udp_flow.h
+++ b/udp_flow.h
@@ -24,7 +24,7 @@ struct udp_flow {
 };
 
 struct udp_flow *udp_at_sidx(flow_sidx_t sidx);
-flow_sidx_t udp_flow_from_sock(const struct ctx *c, union epoll_ref ref,
+flow_sidx_t udp_flow_from_sock(const struct ctx *c, uint8_t pif, in_port_t port,
 			       const union sockaddr_inany *s_in,
 			       const struct timespec *now);
 flow_sidx_t udp_flow_from_tap(const struct ctx *c,
-- 
@@ -24,7 +24,7 @@ struct udp_flow {
 };
 
 struct udp_flow *udp_at_sidx(flow_sidx_t sidx);
-flow_sidx_t udp_flow_from_sock(const struct ctx *c, union epoll_ref ref,
+flow_sidx_t udp_flow_from_sock(const struct ctx *c, uint8_t pif, in_port_t port,
 			       const union sockaddr_inany *s_in,
 			       const struct timespec *now);
 flow_sidx_t udp_flow_from_tap(const struct ctx *c,
-- 
2.49.0