 @@ -1,14 +1,14 @@
-/*	$NetBSD: if.c,v 1.324 2016/02/15 08:08:04 ozaki-r Exp $	*/
+/*	$NetBSD: if.c,v 1.325 2016/02/19 20:05:43 roy Exp $	*/
 /*-
  * Copyright (c) 1999, 2000, 2001, 2008 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by William Studenmund and Jason R. Thorpe.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
 @@ -80,27 +80,27 @@
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
  *	@(#)if.c	8.5 (Berkeley) 1/9/95
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.324 2016/02/15 08:08:04 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.325 2016/02/19 20:05:43 roy Exp $");
 #if defined(_KERNEL_OPT)
 #include "opt_inet.h"
 #include "opt_atalk.h"
 #include "opt_natm.h"
 #include "opt_wlan.h"
 #include "opt_net_mpsafe.h"
 #endif
 #include <sys/param.h>
 #include <sys/mbuf.h>
 #include <sys/systm.h>
 @@ -593,27 +593,27 @@ if_initialize(ifnet_t *ifp)
 	TAILQ_INIT(&ifp->if_addrlist);
 	/*
 	 * Link level name is allocated later by a separate call to
 	 * if_alloc_sadl().
 	 */
 	if (ifp->if_snd.ifq_maxlen == 0)
 		ifp->if_snd.ifq_maxlen = ifqmaxlen;
 	ifp->if_broadcastaddr = 0; /* reliably crash if used uninitialized */
 	ifp->if_link_state = LINK_STATE_UNKNOWN;
-	ifp->if_old_link_state = LINK_STATE_UNKNOWN;
+	ifp->if_link_queue = -1; /* all bits set, see link_state_change() */
 	ifp->if_capenable = 0;
 	ifp->if_csum_flags_tx = 0;
 	ifp->if_csum_flags_rx = 0;
 #ifdef ALTQ
 	ifp->if_snd.altq_type = 0;
 	ifp->if_snd.altq_disc = NULL;
 	ifp->if_snd.altq_flags &= ALTQF_CANTCHANGE;
 	ifp->if_snd.altq_tbr  = NULL;
 	ifp->if_snd.altq_ifp  = ifp;
 #endif
 @@ -1553,102 +1553,205 @@ link_rtrequest(int cmd, struct rtentry *
 	struct ifnet *ifp;
 	if (cmd != RTM_ADD || (ifa = rt->rt_ifa) == NULL ||
 	    (ifp = ifa->ifa_ifp) == NULL || (dst = rt_getkey(rt)) == NULL)
 		return;
 	if ((ifa = ifaof_ifpforaddr(dst, ifp)) != NULL) {
 		rt_replace_ifa(rt, ifa);
 		if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest)
 			ifa->ifa_rtrequest(cmd, rt, info);
+	}
+}
 /*
- * Handle a change in the interface link state.
+ * bitmask macros to manage a densely packed link_state change queue.
- * XXX: We should listen to the routing socket in-kernel rather
+ * Because we need to store LINK_STATE_UNKNOWN(0), LINK_STATE_DOWN(1) and
- * than calling in6_if_link_* functions directly from here.
+ * LINK_STATE_UP(2) we need 2 bits for each state change.
  * As a state change to store is 0, treat all bits set as an unset item.
  */
 #define LQ_ITEM_BITS		2
 #define LQ_ITEM_MASK		((1 << LQ_ITEM_BITS) - 1)
 #define LQ_MASK(i)		(LQ_ITEM_MASK << (i) * LQ_ITEM_BITS)
 #define LINK_STATE_UNSET	LQ_ITEM_MASK
 #define LQ_ITEM(q, i)		(((q) & LQ_MASK((i))) >> (i) * LQ_ITEM_BITS)
 #define LQ_STORE(q, i, v)						      \
 	do {								      \
 		(q) &= ~LQ_MASK((i));					      \
 		(q) |= (v) << (i) * LQ_ITEM_BITS;			      \
 	} while (0 /* CONSTCOND */)
 #define LQ_MAX(q)		((sizeof((q)) * NBBY) / LQ_ITEM_BITS)
 #define LQ_POP(q, v)							      \
 	do {								      \
 		(v) = LQ_ITEM((q), 0);					      \
 		(q) >>= LQ_ITEM_BITS;					      \
 		(q) |= LINK_STATE_UNSET << (LQ_MAX((q)) - 1) * LQ_ITEM_BITS;  \
 	} while (0 /* CONSTCOND */)
 #define LQ_PUSH(q, v)							      \
 	do {								      \
 		(q) >>= LQ_ITEM_BITS;					      \
 		(q) |= (v) << (LQ_MAX((q)) - 1) * LQ_ITEM_BITS;		      \
 	} while (0 /* CONSTCOND */)
 #define LQ_FIND_UNSET(q, i)						      \
 	for ((i) = 0; i < LQ_MAX((q)); (i)++) {				      \
 		if (LQ_ITEM((q), (i)) == LINK_STATE_UNSET)		      \
 			break;						      \
+	}
 /*
  * Handle a change in the interface link state and
  * queue notifications.
  */
 void
 if_link_state_change(struct ifnet *ifp, int link_state)
+{
-	int s;
+	int s, idx;
-	s = splnet();
+	/* Ensure change is to a valid state */
-	if (ifp->if_link_state == link_state) {
+	switch (link_state) {
-		splx(s);
+	case LINK_STATE_UNKNOWN:	/* FALLTHROUGH */
 	case LINK_STATE_DOWN:		/* FALLTHROUGH */
 	case LINK_STATE_UP:
 		break;
 	default:
 #ifdef DEBUG
 		printf("%s: invalid link state %d\n",
 		    ifp->if_xname, link_state);
 #endif
 		return;
+	}
-	ifp->if_link_state = link_state;
+	s = splnet();
 	/* Find the last unset event in the queue. */
 	LQ_FIND_UNSET(ifp->if_link_queue, idx);
 	/*
 	 * Ensure link_state doesn't match the last event in the queue.
 	 * ifp->if_link_state is not checked and set here because
 	 * that would present an inconsistent picture to the system.
 	 */
 	if (idx != 0 &&
 	    LQ_ITEM(ifp->if_link_queue, idx - 1) == (uint8_t)link_state)
 		goto out;
 	/* Handle queue overflow. */
 	if (idx == LQ_MAX(ifp->if_link_queue)) {
 		uint8_t lost;
 		/*
 		 * The DOWN state must be protected from being pushed off
 		 * the queue to ensure that userland will always be
 		 * in a sane state.
 		 * Because DOWN is protected, there is no need to protect
 		 * UNKNOWN.
 		 * It should be invalid to change from any other state to
 		 * UNKNOWN anyway ...
 		 */
 		lost = LQ_ITEM(ifp->if_link_queue, 0);
 		LQ_PUSH(ifp->if_link_queue, (uint8_t)link_state);
 		if (lost == LINK_STATE_DOWN) {
 			lost = LQ_ITEM(ifp->if_link_queue, 0);
 			LQ_STORE(ifp->if_link_queue, 0, LINK_STATE_DOWN);
+		}
 		printf("%s: lost link state change %s\n",
 		    ifp->if_xname,
 		    lost == LINK_STATE_UP ? "UP" :
 		    lost == LINK_STATE_DOWN ? "DOWN" :
 		    "UNKNOWN");
 	} else
 		LQ_STORE(ifp->if_link_queue, idx, (uint8_t)link_state);
 	softint_schedule(ifp->if_link_si);
 out:
 	splx(s);
+}
 /*
  * Handle interface link state change notifications.
  * Must be called at splnet().
  */
 static void
-if_link_state_change_si(void *arg)
+if_link_state_change0(struct ifnet *ifp, int link_state)
+{
 	struct ifnet *ifp = arg;
 	int s;
 	int link_state, old_link_state;
 	struct domain *dp;
-	s = splnet();
+	/* Ensure the change is still valid. */
-	link_state = ifp->if_link_state;
+	if (ifp->if_link_state == link_state)
-	old_link_state = ifp->if_old_link_state;
+		return;
 	ifp->if_old_link_state = ifp->if_link_state;
 #ifdef DEBUG
 	log(LOG_DEBUG, "%s: link state %s (was %s)\n", ifp->if_xname,
 		link_state == LINK_STATE_UP ? "UP" :
 		link_state == LINK_STATE_DOWN ? "DOWN" :
 		"UNKNOWN",
-		 old_link_state == LINK_STATE_UP ? "UP" :
+		ifp->if_link_state == LINK_STATE_UP ? "UP" :
-		old_link_state == LINK_STATE_DOWN ? "DOWN" :
+		ifp->if_link_state == LINK_STATE_DOWN ? "DOWN" :
 		"UNKNOWN");
 #endif
 	/*
 	 * When going from UNKNOWN to UP, we need to mark existing
 	 * addresses as tentative and restart DAD as we may have
 	 * erroneously not found a duplicate.
+	 *
 	 * This needs to happen before rt_ifmsg to avoid a race where
 	 * listeners would have an address and expect it to work right
 	 * away.
 	 */
 	if (link_state == LINK_STATE_UP &&
-	    old_link_state == LINK_STATE_UNKNOWN)
+	    ifp->if_link_state == LINK_STATE_UNKNOWN)
+	{
 		DOMAIN_FOREACH(dp) {
 			if (dp->dom_if_link_state_change != NULL)
 				dp->dom_if_link_state_change(ifp,
 				    LINK_STATE_DOWN);
+		}
+	}
 	ifp->if_link_state = link_state;
 	/* Notify that the link state has changed. */
 	rt_ifmsg(ifp);
 #if NCARP > 0
 	if (ifp->if_carp)
 		carp_carpdev_state(ifp);
 #endif
 	DOMAIN_FOREACH(dp) {
 		if (dp->dom_if_link_state_change != NULL)
 			dp->dom_if_link_state_change(ifp, link_state);
+	}
+}
 /*
  * Process the interface link state change queue.
  */
 static void
 if_link_state_change_si(void *arg)
+{
 	struct ifnet *ifp = arg;
 	int s;
 	uint8_t state;
 	s = splnet();
 	/* Pop a link state change from the queue and process it. */
 	LQ_POP(ifp->if_link_queue, state);
 	if_link_state_change0(ifp, state);
 	/* If there is a link state change to come, schedule it. */
 	if (LQ_ITEM(ifp->if_link_queue, 0) != LINK_STATE_UNSET)
 		softint_schedule(ifp->if_link_si);
 	splx(s);
+}
 /*
  * Default action when installing a local route on a point-to-point
  * interface.
  */
 void
 p2p_rtrequest(int req, struct rtentry *rt,
     __unused const struct rt_addrinfo *info)
+{
 	struct ifnet *ifp = rt->rt_ifp;

 @@ -1,14 +1,14 @@
-/*	$NetBSD: if.h,v 1.197 2016/02/16 01:31:26 ozaki-r Exp $	*/
+/*	$NetBSD: if.h,v 1.198 2016/02/19 20:05:43 roy Exp $	*/
 /*-
  * Copyright (c) 1999, 2000, 2001 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by William Studenmund and Jason R. Thorpe.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
 @@ -341,27 +341,27 @@ typedef struct ifnet {
 					 * same, they are the same ifnet.
 					 */
 	struct sysctllog	*if_sysctl_log;
 	int (*if_initaddr)(struct ifnet *, struct ifaddr *, bool);
 	int (*if_mcastop)(struct ifnet *, const unsigned long,
 	    const struct sockaddr *);
 	int (*if_setflags)(struct ifnet *, const short);
 	struct ifnet_lock *if_ioctl_lock;
 #ifdef _KERNEL /* XXX kvm(3) */
 	struct callout *if_slowtimo_ch;
 	struct krwlock	*if_afdata_lock;
 	struct if_percpuq	*if_percpuq; /* We should remove it in the future */
 	void	*if_link_si;		/* softint to handle link state changes */
-	int	if_old_link_state;	/* previous link state */
+	uint16_t	if_link_queue;	/* masked link state change queue */
 #endif
 } ifnet_t;
 #define	if_mtu		if_data.ifi_mtu
 #define	if_type		if_data.ifi_type
 #define	if_addrlen	if_data.ifi_addrlen
 #define	if_hdrlen	if_data.ifi_hdrlen
 #define	if_metric	if_data.ifi_metric
 #define	if_link_state	if_data.ifi_link_state
 #define	if_baudrate	if_data.ifi_baudrate
 #define	if_ipackets	if_data.ifi_ipackets
 #define	if_ierrors	if_data.ifi_ierrors
 #define	if_opackets	if_data.ifi_opackets