svn commit: r276574 - head/sys/dev/cxgbe/tom

[Navdeep Parhar]

Author: np
Date: Fri Jan  2 21:13:24 2015
New Revision: 276574
URL: https://svnweb.freebsd.org/changeset/base/276574

Log:
  cxgbe/tom: fix the MSS calculation for IPv6 connections handled by the TOE.
  
  MFC after:	1 week

Modified:
  head/sys/dev/cxgbe/tom/t4_cpl_io.c

Modified: head/sys/dev/cxgbe/tom/t4_cpl_io.c
==============================================================================
--- head/sys/dev/cxgbe/tom/t4_cpl_io.c	Fri Jan  2 21:09:54 2015	(r276573)
+++ head/sys/dev/cxgbe/tom/t4_cpl_io.c	Fri Jan  2 21:13:24 2015	(r276574)
@@ -44,6 +44,7 @@ __FBSDID("$FreeBSD$");
 #include <netinet/in.h>
 #include <netinet/in_pcb.h>
 #include <netinet/ip.h>
+#include <netinet/ip6.h>
 #include <netinet/tcp_var.h>
 #define TCPSTATES
 #include <netinet/tcp_fsm.h>
@@ -236,11 +237,20 @@ static void
 assign_rxopt(struct tcpcb *tp, unsigned int opt)
 {
 	struct toepcb *toep = tp->t_toe;
+	struct inpcb *inp = tp->t_inpcb;
 	struct adapter *sc = td_adapter(toep->td);
+	int n;
+
+	INP_LOCK_ASSERT(inp);
 
-	INP_LOCK_ASSERT(tp->t_inpcb);
+	if (inp->inp_inc.inc_flags & INC_ISIPV6)
+		n = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
+	else
+		n = sizeof(struct ip) + sizeof(struct tcphdr);
+	tp->t_maxseg = tp->t_maxopd = sc->params.mtus[G_TCPOPT_MSS(opt)] - n;
 
-	tp->t_maxseg = tp->t_maxopd = sc->params.mtus[G_TCPOPT_MSS(opt)] - 40;
+	CTR4(KTR_CXGBE, "%s: tid %d, mtu_idx %u (%u)", __func__, toep->tid,
+	    G_TCPOPT_MSS(opt), sc->params.mtus[G_TCPOPT_MSS(opt)]);
 
 	if (G_TCPOPT_TSTAMP(opt)) {
 		tp->t_flags |= TF_RCVD_TSTMP;	/* timestamps ok */