From f4e5d73684d6e92eeadfe2a84d92a06d20312a76 Mon Sep 17 00:00:00 2001
From: David Gibson <david@gibson.dropbear.id.au>
Date: Wed, 28 Feb 2024 22:25:12 +1100
Subject: [PATCH] tcp_splice: Merge tcp_splice_new() into its caller

The only caller of tcp_splice_new() is tcp_splice_conn_from_sock().
Both are quite short, and the division of responsibilities between the
two isn't particularly obvious.  Simplify by merging the former into
the latter.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
 tcp_splice.c | 58 ++++++++++++++++++++++------------------------------
 1 file changed, 24 insertions(+), 34 deletions(-)

diff --git a/tcp_splice.c b/tcp_splice.c
index 9bd50e3..269265e 100644
--- a/tcp_splice.c
+++ b/tcp_splice.c
@@ -397,37 +397,6 @@ static int tcp_conn_sock_ns(const struct ctx *c, sa_family_t af)
 	return -1;
 }
 
-/**
- * tcp_splice_new() - Handle new spliced connection
- * @c:		Execution context
- * @conn:	Connection pointer
- * @port:	Destination port, host order
- * @pif:	Originating pif of the splice
- *
- * Return: return code from connect()
- */
-static int tcp_splice_new(const struct ctx *c, struct tcp_splice_conn *conn,
-			  in_port_t dstport, uint8_t pif)
-{
-	sa_family_t af = CONN_V6(conn) ? AF_INET6 : AF_INET;
-	int s1;
-
-	if (pif == PIF_SPLICE) {
-		dstport += c->tcp.fwd_out.delta[dstport];
-		s1 = tcp_conn_sock(c, af);
-	} else {
-		ASSERT(pif == PIF_HOST);
-
-		dstport += c->tcp.fwd_in.delta[dstport];
-		s1 = tcp_conn_sock_ns(c, af);
-	}
-
-	if (s1 < 0)
-		return s1;
-
-	return tcp_splice_connect(c, conn, s1, dstport);
-}
-
 /**
  * tcp_splice_conn_from_sock() - Attempt to init state for a spliced connection
  * @c:		Execution context
@@ -443,9 +412,11 @@ bool tcp_splice_conn_from_sock(const struct ctx *c,
 			       union tcp_listen_epoll_ref ref, union flow *flow,
 			       int s0, const union sockaddr_inany *sa)
 {
+	in_port_t srcport, dstport = ref.port;
 	struct tcp_splice_conn *conn;
 	union inany_addr src;
-	in_port_t srcport;
+	sa_family_t af;
+	int s1;
 
 	ASSERT(c->mode == MODE_PASTA);
 
@@ -453,9 +424,11 @@ bool tcp_splice_conn_from_sock(const struct ctx *c,
 	if (!inany_is_loopback(&src))
 		return false;
 
+	af = inany_v4(&src) ? AF_INET : AF_INET6;
+
 	conn = FLOW_START(flow, FLOW_TCP_SPLICE, tcp_splice, 0);
 
-	conn->flags = inany_v4(&src) ? 0 : SPLICE_V6;
+	conn->flags = af == AF_INET ? 0 : SPLICE_V6;
 	conn->s[0] = s0;
 	conn->s[1] = -1;
 	conn->pipe[0][0] = conn->pipe[0][1] = -1;
@@ -464,7 +437,24 @@ bool tcp_splice_conn_from_sock(const struct ctx *c,
 	if (setsockopt(s0, SOL_TCP, TCP_QUICKACK, &((int){ 1 }), sizeof(int)))
 		flow_trace(conn, "failed to set TCP_QUICKACK on %i", s0);
 
-	if (tcp_splice_new(c, conn, ref.port, ref.pif))
+	if (ref.pif == PIF_SPLICE) {
+		dstport += c->tcp.fwd_out.delta[dstport];
+
+		s1 = tcp_conn_sock(c, af);
+	} else {
+		ASSERT(ref.pif == PIF_HOST);
+
+		dstport += c->tcp.fwd_in.delta[dstport];
+
+		s1 = tcp_conn_sock_ns(c, af);
+	}
+
+	if (s1 < 0) {
+		conn_flag(c, conn, CLOSING);
+		return true;
+	}
+
+	if (tcp_splice_connect(c, conn, s1, dstport))
 		conn_flag(c, conn, CLOSING);
 
 	return true;