Convert trunk(4) to use a detachhook, discussed at b2k13 with many.

While here add a comment explaining detach hooks' order of execution when
destroying/detaching an interface.

3 files changed, 20 insertions, 24 deletions

diff --git a/sys/net/if.c b/sys/net/if.c
index 04f0b6d389d..5a4a7998733 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.275 2013/11/11 09:15:34 mpi Exp $	*/
+/*	$OpenBSD: if.c,v 1.276 2013/11/18 09:16:30 mpi Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -118,10 +118,6 @@
 #include <net/bpf.h>
 #endif
 
-#if NTRUNK > 0
-#include <net/if_trunk.h>
-#endif
-
 #if NBRIDGE > 0
 #include <net/if_bridge.h>
 #endif
@@ -511,14 +507,13 @@ if_detach(struct ifnet *ifp)
 	ifp->if_ioctl = if_detached_ioctl;
 	ifp->if_watchdog = if_detached_watchdog;
 
-	/* Call detach hooks, ie. to remove vlan interfaces */
+	/*
+	 * Call detach hooks from head to tail.  To make sure detach
+	 * hooks are executed in the reverse order they were added, all
+	 * the hooks have to be added to the head!
+	 */
 	dohooks(ifp->if_detachhooks, HOOK_REMOVE | HOOK_FREE);
 
-#if NTRUNK > 0
-	if (ifp->if_type == IFT_IEEE8023ADLAG)
-		trunk_port_ifdetach(ifp);
-#endif
-
 #if NBRIDGE > 0
 	/* Remove the interface from any bridge it is part of.  */
 	if (ifp->if_bridgeport)
diff --git a/sys/net/if_trunk.c b/sys/net/if_trunk.c
index 8ef7749286b..f4bc2ccc492 100644
--- a/sys/net/if_trunk.c
+++ b/sys/net/if_trunk.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_trunk.c,v 1.84 2013/06/20 12:03:40 mpi Exp $	*/
+/*	$OpenBSD: if_trunk.c,v 1.85 2013/11/18 09:16:30 mpi Exp $	*/
 
 /*
  * Copyright (c) 2005, 2006, 2007 Reyk Floeter <reyk@openbsd.org>
@@ -70,6 +70,7 @@ int	 trunk_port_create(struct trunk_softc *, struct ifnet *);
 int	 trunk_port_destroy(struct trunk_port *);
 void	 trunk_port_watchdog(struct ifnet *);
 void	 trunk_port_state(void *);
+void	 trunk_port_ifdetach(void *);
 int	 trunk_port_ioctl(struct ifnet *, u_long, caddr_t);
 struct trunk_port *trunk_port_get(struct trunk_softc *, struct ifnet *);
 int	 trunk_port_checkstacking(struct trunk_softc *);
@@ -381,9 +382,12 @@ trunk_port_create(struct trunk_softc *tr, struct ifnet *ifp)
 	trunk_ether_cmdmulti(tp, SIOCADDMULTI);
 
 	/* Register callback for physical link state changes */
-	if (ifp->if_linkstatehooks != NULL)
-		tp->lh_cookie = hook_establish(ifp->if_linkstatehooks, 1,
-		    trunk_port_state, tp);
+	tp->lh_cookie = hook_establish(ifp->if_linkstatehooks, 1,
+	    trunk_port_state, tp);
+
+	/* Register callback if parent wants to unregister */
+	tp->dh_cookie = hook_establish(ifp->if_detachhooks, 0,
+	    trunk_port_ifdetach, tp);
 
 	if (tr->tr_port_create != NULL)
 		error = (*tr->tr_port_create)(tp);
@@ -433,8 +437,8 @@ trunk_port_destroy(struct trunk_port *tp)
 	ifp->if_ioctl = tp->tp_ioctl;
 	ifp->if_tp = NULL;
 
-	if (ifp->if_linkstatehooks != NULL)
-		hook_disestablish(ifp->if_linkstatehooks, tp->lh_cookie);
+	hook_disestablish(ifp->if_linkstatehooks, tp->lh_cookie);
+	hook_disestablish(ifp->if_detachhooks, tp->dh_cookie);
 
 	/* Finally, remove the port from the trunk */
 	SLIST_REMOVE(&tr->tr_ports, tp, trunk_port, tp_entries);
@@ -544,12 +548,9 @@ trunk_port_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 }
 
 void
-trunk_port_ifdetach(struct ifnet *ifp)
+trunk_port_ifdetach(void *arg)
 {
-	struct trunk_port *tp;
-
-	if ((tp = (struct trunk_port *)ifp->if_tp) == NULL)
-		return;
+	struct trunk_port *tp = (struct trunk_port *)arg;
 
 	trunk_port_destroy(tp);
 }
diff --git a/sys/net/if_trunk.h b/sys/net/if_trunk.h
index 2d0763527ee..0a2a6b647a3 100644
--- a/sys/net/if_trunk.h
+++ b/sys/net/if_trunk.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_trunk.h,v 1.17 2011/07/04 04:29:17 claudio Exp $	*/
+/*	$OpenBSD: if_trunk.h,v 1.18 2013/11/18 09:16:30 mpi Exp $	*/
 
 /*
  * Copyright (c) 2005, 2006, 2007 Reyk Floeter <reyk@openbsd.org>
@@ -136,6 +136,7 @@ struct trunk_port {
 	u_int32_t			tp_prio;	/* port priority */
 	u_int32_t			tp_flags;	/* port flags */
 	void				*lh_cookie;	/* if state hook */
+	void				*dh_cookie;	/* if detach hook */
 
 	/* Redirected callbacks */
 	void	(*tp_watchdog)(struct ifnet *);
@@ -219,7 +220,6 @@ struct trunk_lb {
 	struct trunk_port	*lb_ports[TRUNK_MAX_PORTS];
 };
 
-void	 	trunk_port_ifdetach(struct ifnet *);
 int	 	trunk_input(struct ifnet *, struct ether_header *,
 		    struct mbuf *);
 int		trunk_enqueue(struct ifnet *, struct mbuf *);