Incorporate TCP offload hooks in to core TCP code.

  - Rename output routines tcp_gen_* -> tcp_output_*.
  - Rename notification routines that turn in to no-ops in the absence of TOE
    from tcp_gen_* -> tcp_offload_*.
  - Fix some minor comment nits.
  - Add a /* FALLTHROUGH */

Reviewed by: Sam Leffler, Robert Watson, and Mike Silbersack

3 files changed, 34 insertions, 21 deletions

diff --git a/sys/netinet/tcp_offload.h b/sys/netinet/tcp_offload.h
index 33d73ee..21ecba4 100644
--- a/sys/netinet/tcp_offload.h
+++ b/sys/netinet/tcp_offload.h
@@ -216,8 +216,10 @@ EVENTHANDLER_DECLARE(tcp_offload_listen_stop, tcp_offload_listen_stop_fn);
 int	tcp_offload_connect(struct socket *so, struct sockaddr *nam);
 
 /*
- * The tcp_gen_* routines are wrappers around the toe_usrreqs calls,
- * in the non-offloaded case they translate to tcp_output.
+ * The tcp_output_* routines are wrappers around the toe_usrreqs calls
+ * which trigger packet transmission. In the non-offloaded case they
+ * translate to tcp_output. The tcp_offload_* routines notify TOE
+ * of specific events. I the non-offloaded case they are no-ops.
  *
  * Listen is a special case because it is a 1 to many relationship
  * and there can be more than one offload driver in the system.
@@ -233,7 +235,7 @@ int	tcp_offload_connect(struct socket *so, struct sockaddr *nam);
 #define	SO_OFFLOADABLE(so)	((so->so_options & SO_NO_OFFLOAD) == 0)
 
 static __inline int
-tcp_gen_connect(struct socket *so, struct sockaddr *nam)
+tcp_output_connect(struct socket *so, struct sockaddr *nam)
 {
 	struct tcpcb *tp = sototcpcb(so);
 	int error;
@@ -251,7 +253,7 @@ tcp_gen_connect(struct socket *so, struct sockaddr *nam)
 }
 
 static __inline int
-tcp_gen_send(struct tcpcb *tp)
+tcp_output_send(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
@@ -262,7 +264,7 @@ tcp_gen_send(struct tcpcb *tp)
 }
 
 static __inline int
-tcp_gen_rcvd(struct tcpcb *tp)
+tcp_output_rcvd(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
@@ -273,7 +275,7 @@ tcp_gen_rcvd(struct tcpcb *tp)
 }
 
 static __inline int
-tcp_gen_disconnect(struct tcpcb *tp)
+tcp_output_disconnect(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
@@ -284,7 +286,7 @@ tcp_gen_disconnect(struct tcpcb *tp)
 }
 
 static __inline int
-tcp_gen_reset(struct tcpcb *tp)
+tcp_output_reset(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
@@ -295,7 +297,7 @@ tcp_gen_reset(struct tcpcb *tp)
 }
 
 static __inline void
-tcp_gen_detach(struct tcpcb *tp)
+tcp_offload_detach(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
@@ -305,7 +307,7 @@ tcp_gen_detach(struct tcpcb *tp)
 }
 
 static __inline void
-tcp_gen_listen_open(struct tcpcb *tp)
+tcp_offload_listen_open(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
@@ -315,7 +317,7 @@ tcp_gen_listen_open(struct tcpcb *tp)
 }
 
 static __inline void
-tcp_gen_listen_close(struct tcpcb *tp)
+tcp_offload_listen_close(struct tcpcb *tp)
 {
 
 #ifndef TCP_OFFLOAD_DISABLE
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index 7d2a677..214dc3e 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -85,6 +85,7 @@ __FBSDID("$FreeBSD$");
 #include <netinet/tcp_timer.h>
 #include <netinet/tcp_var.h>
 #include <netinet/tcp_syncache.h>
+#include <netinet/tcp_offload.h>
 #ifdef INET6
 #include <netinet6/tcp6_var.h>
 #endif
@@ -651,7 +652,7 @@ tcp_drop(struct tcpcb *tp, int errno)
 
 	if (TCPS_HAVERCVDSYN(tp->t_state)) {
 		tp->t_state = TCPS_CLOSED;
-		(void) tcp_output(tp);
+		(void) tcp_output_reset(tp);
 		tcpstat.tcps_drops++;
 	} else
 		tcpstat.tcps_conndrops++;
@@ -749,6 +750,9 @@ tcp_discardcb(struct tcpcb *tp)
 		tp->t_segqlen--;
 		tcp_reass_qsize--;
 	}
+	/* Disconnect offload device, if any. */
+	tcp_offload_detach(tp);
+		
 	tcp_free_sackholes(tp);
 	inp->inp_ppcb = NULL;
 	tp->t_inpcb = NULL;
@@ -768,6 +772,9 @@ tcp_close(struct tcpcb *tp)
 	INP_INFO_WLOCK_ASSERT(&tcbinfo);
 	INP_LOCK_ASSERT(inp);
 
+	/* Notify any offload devices of listener close */
+	if (tp->t_state == TCPS_LISTEN)
+		tcp_offload_listen_close(tp);
 	in_pcbdrop(inp);
 	tcpstat.tcps_closed++;
 	KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL"));
@@ -1562,7 +1569,7 @@ tcp_mtudisc(struct inpcb *inp, int errno)
 	tp->snd_recover = tp->snd_max;
 	if (tp->t_flags & TF_SACK_PERMIT)
 		EXIT_FASTRECOVERY(tp);
-	tcp_output(tp);
+	tcp_output_send(tp);
 	return (inp);
 }
 
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
index 77413cb..02ab9d0 100644
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -85,6 +85,7 @@ __FBSDID("$FreeBSD$");
 #ifdef TCPDEBUG
 #include <netinet/tcp_debug.h>
 #endif
+#include <netinet/tcp_offload.h>
 
 /*
  * TCP protocol interface to socket abstraction.
@@ -385,6 +386,7 @@ tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
 	if (error == 0) {
 		tp->t_state = TCPS_LISTEN;
 		solisten_proto(so, backlog);
+		tcp_offload_listen_open(tp);
 	}
 	SOCK_UNLOCK(so);
 
@@ -476,7 +478,7 @@ tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 	TCPDEBUG1();
 	if ((error = tcp_connect(tp, nam, td)) != 0)
 		goto out;
-	error = tcp_output(tp);
+	error = tcp_output_connect(so, nam);
 out:
 	TCPDEBUG2(PRU_CONNECT);
 	INP_UNLOCK(inp);
@@ -528,7 +530,7 @@ tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 		inp->inp_vflag &= ~INP_IPV6;
 		if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
 			goto out;
-		error = tcp_output(tp);
+		error = tcp_output_connect(so, nam);
 		goto out;
 	}
 	inp->inp_vflag &= ~INP_IPV4;
@@ -536,7 +538,7 @@ tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 	inp->inp_inc.inc_isipv6 = 1;
 	if ((error = tcp6_connect(tp, nam, td)) != 0)
 		goto out;
-	error = tcp_output(tp);
+	error = tcp_output_connect(so, nam);
 
 out:
 	TCPDEBUG2(PRU_CONNECT);
@@ -703,7 +705,7 @@ tcp_usr_shutdown(struct socket *so)
 	TCPDEBUG1();
 	socantsendmore(so);
 	tcp_usrclosed(tp);
-	error = tcp_output(tp);
+	error = tcp_output_disconnect(tp);
 
 out:
 	TCPDEBUG2(PRU_SHUTDOWN);
@@ -733,7 +735,7 @@ tcp_usr_rcvd(struct socket *so, int flags)
 	}
 	tp = intotcpcb(inp);
 	TCPDEBUG1();
-	tcp_output(tp);
+	tcp_output_rcvd(tp);
 
 out:
 	TCPDEBUG2(PRU_RCVD);
@@ -838,7 +840,7 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
 		if (tp != NULL) {
 			if (flags & PRUS_MORETOCOME)
 				tp->t_flags |= TF_MORETOCOME;
-			error = tcp_output(tp);
+			error = tcp_output_send(tp);
 			if (flags & PRUS_MORETOCOME)
 				tp->t_flags &= ~TF_MORETOCOME;
 		}
@@ -889,7 +891,7 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
 		}
 		tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 		tp->t_flags |= TF_FORCEDATA;
-		error = tcp_output(tp);
+		error = tcp_output_send(tp);
 		tp->t_flags &= ~TF_FORCEDATA;
 	}
 out:
@@ -1489,7 +1491,7 @@ tcp_disconnect(struct tcpcb *tp)
 		sbflush(&so->so_rcv);
 		tcp_usrclosed(tp);
 		if (!(inp->inp_vflag & INP_DROPPED))
-			tcp_output(tp);
+			tcp_output_disconnect(tp);
 	}
 }
 
@@ -1511,8 +1513,10 @@ tcp_usrclosed(struct tcpcb *tp)
 	INP_LOCK_ASSERT(tp->t_inpcb);
 
 	switch (tp->t_state) {
-	case TCPS_CLOSED:
 	case TCPS_LISTEN:
+		tcp_offload_listen_close(tp);
+		/* FALLTHROUGH */
+	case TCPS_CLOSED:
 		tp->t_state = TCPS_CLOSED;
 		tp = tcp_close(tp);
 		/*