[PATCH v2 1/8] tcp: inline tcp_l2_buf_fill_headers()

It only calls tcp_fill_headers4() and tcp_fill_headers6() according
to the connection IP version.

We can inline them in tcp_data_to_tap() that already has a switch
on the IP version. In tcp_send_flag(), it will ease to separate code
from the common part and the buffer/vhost-user parts.

Signed-off-by: Laurent Vivier <lvivier(a)redhat.com>
---
 tcp.c | 54 +++++++++++++++++++-----------------------------------
 1 file changed, 19 insertions(+), 35 deletions(-)

diff --git a/tcp.c b/tcp.c
index 06acb41e4d90..6f221995f3bc 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1401,37 +1401,6 @@ static size_t tcp_fill_headers6(const struct ctx *c,
 	return l4len;
 }
 
-/**
- * tcp_l2_buf_fill_headers() - Fill 802.3, IP, TCP headers in pre-cooked buffers
- * @c:		Execution context
- * @conn:	Connection pointer
- * @iov:	Pointer to an array of iovec of TCP pre-cooked buffers
- * @dlen:	TCP payload length
- * @check:	Checksum, if already known
- * @seq:	Sequence number for this segment
- *
- * Return: IP payload length, host order
- */
-static size_t tcp_l2_buf_fill_headers(const struct ctx *c,
-				      const struct tcp_tap_conn *conn,
-				      struct iovec *iov, size_t dlen,
-				      const uint16_t *check, uint32_t seq)
-{
-	const struct in_addr *a4 = inany_v4(&conn->faddr);
-
-	if (a4) {
-		return tcp_fill_headers4(c, conn, iov[TCP_IOV_TAP].iov_base,
-					 iov[TCP_IOV_IP].iov_base,
-					 iov[TCP_IOV_PAYLOAD].iov_base, dlen,
-					 check, seq);
-	}
-
-	return tcp_fill_headers6(c, conn, iov[TCP_IOV_TAP].iov_base,
-				 iov[TCP_IOV_IP].iov_base,
-				 iov[TCP_IOV_PAYLOAD].iov_base, dlen,
-				 seq);
-}
-
 /**
  * tcp_update_seqack_wnd() - Update ACK sequence and window to guest/tap
  * @c:		Execution context
@@ -1642,8 +1611,17 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn,
int flags)
 	th->syn = !!(flags & SYN);
 	th->fin = !!(flags & FIN);
 
-	l4len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL,
-					conn->seq_to_tap);
+	if (CONN_V4(conn)) {
+		l4len = tcp_fill_headers4(c, conn, iov[TCP_IOV_TAP].iov_base,
+					  iov[TCP_IOV_IP].iov_base,
+					  iov[TCP_IOV_PAYLOAD].iov_base, optlen,
+					  NULL, conn->seq_to_tap);
+	} else {
+		l4len = tcp_fill_headers6(c, conn, iov[TCP_IOV_TAP].iov_base,
+					  iov[TCP_IOV_IP].iov_base,
+					  iov[TCP_IOV_PAYLOAD].iov_base, optlen,
+					  conn->seq_to_tap);
+	}
 	iov[TCP_IOV_PAYLOAD].iov_len = l4len;
 
 	if (th->ack) {
@@ -2146,7 +2124,10 @@ static void tcp_data_to_tap(const struct ctx *c, struct
tcp_tap_conn *conn,
 		tcp4_seq_update[tcp4_payload_used].len = dlen;
 
 		iov = tcp4_l2_iov[tcp4_payload_used++];
-		l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, check, seq);
+		l4len = tcp_fill_headers4(c, conn, iov[TCP_IOV_TAP].iov_base,
+					  iov[TCP_IOV_IP].iov_base,
+					  iov[TCP_IOV_PAYLOAD].iov_base, dlen,
+					  check, seq);
 		iov[TCP_IOV_PAYLOAD].iov_len = l4len;
 		if (tcp4_payload_used > TCP_FRAMES_MEM - 1)
 			tcp_payload_flush(c);
@@ -2155,7 +2136,10 @@ static void tcp_data_to_tap(const struct ctx *c, struct
tcp_tap_conn *conn,
 		tcp6_seq_update[tcp6_payload_used].len = dlen;
 
 		iov = tcp6_l2_iov[tcp6_payload_used++];
-		l4len = tcp_l2_buf_fill_headers(c, conn, iov, dlen, NULL, seq);
+		l4len = tcp_fill_headers6(c, conn, iov[TCP_IOV_TAP].iov_base,
+				 iov[TCP_IOV_IP].iov_base,
+				 iov[TCP_IOV_PAYLOAD].iov_base, dlen,
+				 seq);
 		iov[TCP_IOV_PAYLOAD].iov_len = l4len;
 		if (tcp6_payload_used > TCP_FRAMES_MEM - 1)
 			tcp_payload_flush(c);
-- 
2.44.0