Add SIOCGIFHARDMTU to allow retrieving the driver's maximum supported MTU

looks fine reyk@ ok mikeb@

4 files changed, 17 insertions, 4 deletions

diff --git a/sys/net/if.c b/sys/net/if.c
index b6ccd30202f..b0a3cb87c13 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.247 2012/10/23 17:41:00 claudio Exp $	*/
+/*	$OpenBSD: if.c,v 1.248 2012/11/23 20:12:03 sthen Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -1268,6 +1268,10 @@ ifioctl(struct socket *so, u_long cmd, caddr_t data, struct proc *p)
 		ifr->ifr_mtu = ifp->if_mtu;
 		break;
 
+	case SIOCGIFHARDMTU:
+		ifr->ifr_hardmtu = ifp->if_hardmtu;
+		break;
+
 	case SIOCGIFDATA:
 		error = copyout((caddr_t)&ifp->if_data, ifr->ifr_data,
 		    sizeof(ifp->if_data));
diff --git a/sys/net/if.h b/sys/net/if.h
index e00ffa3dc98..0cf96f90ece 100644
--- a/sys/net/if.h
+++ b/sys/net/if.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.h,v 1.136 2012/11/11 04:45:37 deraadt Exp $	*/
+/*	$OpenBSD: if.h,v 1.137 2012/11/23 20:12:03 sthen Exp $	*/
 /*	$NetBSD: if.h,v 1.23 1996/05/07 02:40:27 thorpej Exp $	*/
 
 /*
@@ -639,6 +639,7 @@ struct	ifreq {
 #define	ifr_flags	ifr_ifru.ifru_flags	/* flags */
 #define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
 #define	ifr_mtu		ifr_ifru.ifru_metric	/* mtu (overload) */
+#define	ifr_hardmtu	ifr_ifru.ifru_metric	/* hardmtu (overload) */
 #define	ifr_media	ifr_ifru.ifru_metric	/* media options (overload) */
 #define	ifr_rdomainid	ifr_ifru.ifru_metric	/* VRF instance (overload) */
 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
diff --git a/sys/net/if_gre.c b/sys/net/if_gre.c
index 88f3ba3bd3c..7a9eeee4a49 100644
--- a/sys/net/if_gre.c
+++ b/sys/net/if_gre.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: if_gre.c,v 1.58 2012/04/14 09:39:47 yasuoka Exp $ */
+/*      $OpenBSD: if_gre.c,v 1.59 2012/11/23 20:12:03 sthen Exp $ */
 /*	$NetBSD: if_gre.c,v 1.9 1999/10/25 19:18:11 drochner Exp $ */
 
 /*
@@ -475,6 +475,9 @@ gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 	case SIOCGIFMTU:
 		ifr->ifr_mtu = sc->sc_if.if_mtu;
 		break;
+	case SIOCGIFHARDMTU:
+		ifr->ifr_hardmtu = sc->sc_if.if_hardmtu;
+		break;
 	case SIOCADDMULTI:
 	case SIOCDELMULTI:
 		if (ifr == 0) {
diff --git a/sys/net/if_spppsubr.c b/sys/net/if_spppsubr.c
index 8e505949ad5..91a365262c4 100644
--- a/sys/net/if_spppsubr.c
+++ b/sys/net/if_spppsubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_spppsubr.c,v 1.98 2012/07/24 15:16:20 deraadt Exp $	*/
+/*	$OpenBSD: if_spppsubr.c,v 1.99 2012/11/23 20:12:03 sthen Exp $	*/
 /*
  * Synchronous PPP/Cisco link level subroutines.
  * Keepalive protocol implemented in both Cisco and PPP modes.
@@ -1117,6 +1117,11 @@ sppp_ioctl(struct ifnet *ifp, u_long cmd, void *data)
 		ifr->ifr_mtu = ifp->if_mtu;
 		break;
 #endif
+#ifdef SIOCGIFHARDMTU
+	case SIOCGIFHARDMTU:
+		ifr->ifr_hardmtu = ifp->if_hardmtu;
+		break;
+#endif
 #ifdef SLIOCGETMTU
 	case SLIOCGETMTU:
 		*(short*)data = ifp->if_mtu;