- Updated TOE support in the kernel.

- Stateful TCP offload drivers for Terminator 3 and 4 (T3 and T4) ASICs.
  These are available as t3_tom and t4_tom modules that augment cxgb(4)
  and cxgbe(4) respectively.  The cxgb/cxgbe drivers continue to work as
  usual with or without these extra features.

- iWARP driver for Terminator 3 ASIC (kernel verbs).  T4 iWARP in the
  works and will follow soon.

Build-tested with make universe.

30s overview
============
What interfaces support TCP offload?  Look for TOE4 and/or TOE6 in the
capabilities of an interface:
# ifconfig -m | grep TOE

Enable/disable TCP offload on an interface (just like any other ifnet
capability):
# ifconfig cxgbe0 toe
# ifconfig cxgbe0 -toe

Which connections are offloaded?  Look for toe4 and/or toe6 in the
output of netstat and sockstat:
# netstat -np tcp | grep toe
# sockstat -46c | grep toe

Reviewed by:	bz, gnn
Sponsored by:	Chelsio communications.
MFC after:	~3 months (after 9.1, and after ensuring MFC is feasible)

1 files changed, 8 insertions, 0 deletions

diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c
index 8e0f369..1881c54 100644
--- a/sys/netinet/tcp_output.c
+++ b/sys/netinet/tcp_output.c
@@ -75,6 +75,9 @@ __FBSDID("$FreeBSD$");
 #ifdef TCPDEBUG
 #include <netinet/tcp_debug.h>
 #endif
+#ifdef TCP_OFFLOAD
+#include <netinet/tcp_offload.h>
+#endif
 
 #ifdef IPSEC
 #include <netipsec/ipsec.h>
@@ -191,6 +194,11 @@ tcp_output(struct tcpcb *tp)
 
 	INP_WLOCK_ASSERT(tp->t_inpcb);
 
+#ifdef TCP_OFFLOAD
+	if (tp->t_flags & TF_TOE)
+		return (tcp_offload_output(tp));
+#endif
+
 	/*
 	 * Determine length of data that should be transmitted,
 	 * and flags that will be used.