From 393a4e5fcc5241f6958519115c3b49d029fddd90 Mon Sep 17 00:00:00 2001
From: rmacklem <rmacklem@ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f>
Date: Tue, 6 May 2014 02:44:01 +0000
Subject: [PATCH] MFC: r264469, r264498 Lagg did not set the value of
 if_hw_tsomax, so when lagg was stacked on top of network interfaces that set
 if_hw_tsomax, tcp_output() would see the default value instead of the value
 set by the network interface(s). This patch modifies lagg so that it sets
 if_hw_tsomax to the minimum of the value(s) for the underlying network
 interfaces.

git-svn-id: svn://svn.freebsd.org/base/stable/10@265412 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
---
 sys/net/if_lagg.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/sys/net/if_lagg.c b/sys/net/if_lagg.c
index beae0b616..bf4d9d78f 100644
--- a/sys/net/if_lagg.c
+++ b/sys/net/if_lagg.c
@@ -54,11 +54,11 @@ __FBSDID("$FreeBSD$");
 
 #if defined(INET) || defined(INET6)
 #include <netinet/in.h>
+#include <netinet/ip.h>
 #endif
 #ifdef INET
 #include <netinet/in_systm.h>
 #include <netinet/if_ether.h>
-#include <netinet/ip.h>
 #endif
 
 #ifdef INET6
@@ -448,6 +448,11 @@ lagg_capabilities(struct lagg_softc *sc)
 	struct lagg_port *lp;
 	int cap = ~0, ena = ~0;
 	u_long hwa = ~0UL;
+#if defined(INET) || defined(INET6)
+	u_int hw_tsomax = IP_MAXPACKET;	/* Initialize to the maximum value. */
+#else
+	u_int hw_tsomax = ~0;	/* if_hw_tsomax is only for INET/INET6, but.. */
+#endif
 
 	LAGG_WLOCK_ASSERT(sc);
 
@@ -456,6 +461,10 @@ lagg_capabilities(struct lagg_softc *sc)
 		cap &= lp->lp_ifp->if_capabilities;
 		ena &= lp->lp_ifp->if_capenable;
 		hwa &= lp->lp_ifp->if_hwassist;
+		/* Set to the minimum value of the lagg ports. */
+		if (lp->lp_ifp->if_hw_tsomax < hw_tsomax &&
+		    lp->lp_ifp->if_hw_tsomax > 0)
+			hw_tsomax = lp->lp_ifp->if_hw_tsomax;
 	}
 	cap = (cap == ~0 ? 0 : cap);
 	ena = (ena == ~0 ? 0 : ena);
@@ -463,10 +472,12 @@ lagg_capabilities(struct lagg_softc *sc)
 
 	if (sc->sc_ifp->if_capabilities != cap ||
 	    sc->sc_ifp->if_capenable != ena ||
-	    sc->sc_ifp->if_hwassist != hwa) {
+	    sc->sc_ifp->if_hwassist != hwa ||
+	    sc->sc_ifp->if_hw_tsomax != hw_tsomax) {
 		sc->sc_ifp->if_capabilities = cap;
 		sc->sc_ifp->if_capenable = ena;
 		sc->sc_ifp->if_hwassist = hwa;
+		sc->sc_ifp->if_hw_tsomax = hw_tsomax;
 		getmicrotime(&sc->sc_ifp->if_lastchange);
 
 		if (sc->sc_ifflags & IFF_DEBUG)
-- 
2.45.0