svn commit: r264469 - head/sys/net

[Rick Macklem]

Author: rmacklem
Date: Mon Apr 14 20:34:48 2014
New Revision: 264469
URL: http://svnweb.freebsd.org/changeset/base/264469

Log:
  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.
  
  Reviewed by:	glebius
  MFC after:	2 weeks

Modified:
  head/sys/net/if_lagg.c

Modified: head/sys/net/if_lagg.c
==============================================================================
--- head/sys/net/if_lagg.c	Mon Apr 14 19:00:20 2014	(r264468)
+++ head/sys/net/if_lagg.c	Mon Apr 14 20:34:48 2014	(r264469)
@@ -448,6 +448,7 @@ lagg_capabilities(struct lagg_softc *sc)
 	struct lagg_port *lp;
 	int cap = ~0, ena = ~0;
 	u_long hwa = ~0UL;
+	u_int hw_tsomax = IP_MAXPACKET;	/* Initialize to the maximum value. */
 
 	LAGG_WLOCK_ASSERT(sc);
 
@@ -456,6 +457,10 @@ 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 +468,12 @@ 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)