turn the linkstate hooks into a task list, like the detach hooks.

this is largely mechanical, except for carp. this moves the addition
of the carp link state hook after we're committed to using the new
interface as a carpdev. because the add can't fail, we avoid a
complicated unwind dance. also, this tweaks the carp linkstate hook
so it only updates the relevant carp interface, not all of the
carpdevs on the parent.

hrvoje popovski has tested an early version of this diff and it's
generally ok, but there's some splasserts that this diff fires that
i'll fix in an upcoming diff.

ok claudio@

1 files changed, 27 insertions, 47 deletions

diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
index da763361493..bd6d5465615 100644
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_carp.c,v 1.339 2019/11/06 03:51:26 dlg Exp $	*/
+/*	$OpenBSD: ip_carp.c,v 1.340 2019/11/07 07:36:32 dlg Exp $	*/
 
 /*
  * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
@@ -132,7 +132,7 @@ struct carp_softc {
 #define	sc_if		sc_ac.ac_if
 #define	sc_carpdev	sc_ac.ac_if.if_carpdev
 	void *ah_cookie;
-	void *lh_cookie;
+	struct task sc_ltask;
 	struct task sc_dtask;
 	struct ip_moptions sc_imo;
 #ifdef INET6
@@ -808,6 +808,7 @@ carp_clone_create(struct if_clone *ifc, int unit)
 		return (ENOMEM);
 	}
 
+	task_set(&sc->sc_ltask, carp_carpdev_state, sc);
 	task_set(&sc->sc_dtask, carpdetach, sc);
 
 	sc->sc_suppress = 0;
@@ -956,7 +957,7 @@ carpdetach(void *arg)
 		ifpromisc(ifp0, 0);
 	sc->sc_carpdev = NULL;
 
-	hook_disestablish(ifp0->if_linkstatehooks, sc->lh_cookie);
+	if_linkstatehook_del(ifp0, &sc->sc_ltask);
 	if_detachhook_del(ifp0, &sc->sc_dtask);
 }
 
@@ -1687,20 +1688,13 @@ carp_set_ifp(struct carp_softc *sc, struct ifnet *ifp0)
 	if (ifp0->if_type != IFT_ETHER)
 		return (EINVAL);
 
-	sc->lh_cookie = hook_establish(ifp0->if_linkstatehooks, 1,
-	    carp_carpdev_state, ifp0);
-	if (sc->lh_cookie == NULL)
-		return (ENOMEM);
-
 	cif = &ifp0->if_carp;
 	if (SRPL_EMPTY_LOCKED(cif)) {
 		if ((error = ifpromisc(ifp0, 1)))
-			goto rm_lh;
+			return (error);
 
-	} else if (carp_check_dup_vhids(sc, cif, NULL)) {
-		error = EINVAL;
-		goto rm_lh;
-	}
+	} else if (carp_check_dup_vhids(sc, cif, NULL))
+		return (EINVAL);
 
 	/* detach from old interface */
 	if (sc->sc_carpdev != NULL)
@@ -1708,6 +1702,8 @@ carp_set_ifp(struct carp_softc *sc, struct ifnet *ifp0)
 
 	/* attach carp interface to physical interface */
 	if_detachhook_add(ifp0, &sc->sc_dtask);
+	if_linkstatehook_add(ifp0, &sc->sc_ltask);
+
 	sc->sc_carpdev = ifp0;
 	sc->sc_if.if_capabilities = ifp0->if_capabilities &
 	    IFCAP_CSUM_MASK;
@@ -1745,14 +1741,9 @@ carp_set_ifp(struct carp_softc *sc, struct ifnet *ifp0)
 	/* Change input handler of the physical interface. */
 	if_ih_insert(ifp0, carp_input, NULL);
 
-	carp_carpdev_state(ifp0);
+	carp_carpdev_state(sc);
 
 	return (0);
-
-rm_lh:
-	hook_disestablish(ifp0->if_linkstatehooks, sc->lh_cookie);
-
-	return (error);
 }
 
 void
@@ -2465,35 +2456,24 @@ carp_group_demote_count(struct carp_softc *sc)
 void
 carp_carpdev_state(void *v)
 {
-	struct srpl *cif;
-	struct carp_softc *sc;
-	struct ifnet *ifp0 = v;
-
-	if (ifp0->if_type != IFT_ETHER)
-		return;
-
-	cif = &ifp0->if_carp;
-
-	KERNEL_ASSERT_LOCKED(); /* touching if_carp */
-
-	SRPL_FOREACH_LOCKED(sc, cif, sc_list) {
-		int suppressed = sc->sc_suppress;
+	struct carp_softc *sc = v;
+	struct ifnet *ifp0 = sc->sc_carpdev;
+	int suppressed = sc->sc_suppress;
 
-		if (sc->sc_carpdev->if_link_state == LINK_STATE_DOWN ||
-		    !(sc->sc_carpdev->if_flags & IFF_UP)) {
-			sc->sc_if.if_flags &= ~IFF_RUNNING;
-			carp_del_all_timeouts(sc);
-			carp_set_state_all(sc, INIT);
-			sc->sc_suppress = 1;
-			carp_setrun_all(sc, 0);
-			if (!suppressed)
-				carp_group_demote_adj(&sc->sc_if, 1, "carpdev");
-		} else if (suppressed) {
-			carp_set_state_all(sc, INIT);
-			sc->sc_suppress = 0;
-			carp_setrun_all(sc, 0);
-			carp_group_demote_adj(&sc->sc_if, -1, "carpdev");
-		}
+	if (ifp0->if_link_state == LINK_STATE_DOWN ||
+	    !(ifp0->if_flags & IFF_UP)) {
+		sc->sc_if.if_flags &= ~IFF_RUNNING;
+		carp_del_all_timeouts(sc);
+		carp_set_state_all(sc, INIT);
+		sc->sc_suppress = 1;
+		carp_setrun_all(sc, 0);
+		if (!suppressed)
+			carp_group_demote_adj(&sc->sc_if, 1, "carpdev");
+	} else if (suppressed) {
+		carp_set_state_all(sc, INIT);
+		sc->sc_suppress = 0;
+		carp_setrun_all(sc, 0);
+		carp_group_demote_adj(&sc->sc_if, -1, "carpdev");
 	}
 }