Make ALTQ cope with disappearing interfaces (particularly common with mpd

and netgraph in gernal).  This also allows to add queues for an interface
that is not yet existing (you have to provide the bandwidth for the
interface, however).

PR:		kern/106400, kern/117827
MFC after:	2 weeks

3 files changed, 129 insertions, 2 deletions

diff --git a/sys/contrib/pf/net/pf_if.c b/sys/contrib/pf/net/pf_if.c
index f62b497..2b82375 100644
--- a/sys/contrib/pf/net/pf_if.c
+++ b/sys/contrib/pf/net/pf_if.c
@@ -893,6 +893,9 @@ pfi_attach_ifnet_event(void *arg __unused, struct ifnet *ifp)
 {
 	PF_LOCK();
 	pfi_attach_ifnet(ifp);
+#ifdef ALTQ
+	pf_altq_ifnet_event(ifp, 0);
+#endif
 	PF_UNLOCK();
 }
 
@@ -901,6 +904,9 @@ pfi_detach_ifnet_event(void *arg __unused, struct ifnet *ifp)
 {
 	PF_LOCK();
 	pfi_detach_ifnet(ifp);
+#ifdef ALTQ
+	pf_altq_ifnet_event(ifp, 1);
+#endif
 	PF_UNLOCK();
 }
 
diff --git a/sys/contrib/pf/net/pf_ioctl.c b/sys/contrib/pf/net/pf_ioctl.c
index 6314b4c..f9110cb 100644
--- a/sys/contrib/pf/net/pf_ioctl.c
+++ b/sys/contrib/pf/net/pf_ioctl.c
@@ -787,7 +787,12 @@ pf_begin_altq(u_int32_t *ticket)
 	/* Purge the old altq list */
 	while ((altq = TAILQ_FIRST(pf_altqs_inactive)) != NULL) {
 		TAILQ_REMOVE(pf_altqs_inactive, altq, entries);
+#ifdef __FreeBSD__
+		if (altq->qname[0] == 0 &&
+		    (altq->local_flags & PFALTQ_FLAG_IF_REMOVED) == 0) {
+#else
 		if (altq->qname[0] == 0) {
+#endif
 			/* detach and destroy the discipline */
 			error = altq_remove(altq);
 		} else
@@ -812,7 +817,12 @@ pf_rollback_altq(u_int32_t ticket)
 	/* Purge the old altq list */
 	while ((altq = TAILQ_FIRST(pf_altqs_inactive)) != NULL) {
 		TAILQ_REMOVE(pf_altqs_inactive, altq, entries);
+#ifdef __FreeBSD__
+		if (altq->qname[0] == 0 &&
+		    (altq->local_flags & PFALTQ_FLAG_IF_REMOVED) == 0) {
+#else
 		if (altq->qname[0] == 0) {
+#endif
 			/* detach and destroy the discipline */
 			error = altq_remove(altq);
 		} else
@@ -842,7 +852,12 @@ pf_commit_altq(u_int32_t ticket)
 
 	/* Attach new disciplines */
 	TAILQ_FOREACH(altq, pf_altqs_active, entries) {
+#ifdef __FreeBSD__
+		if (altq->qname[0] == 0 &&
+		    (altq->local_flags & PFALTQ_FLAG_IF_REMOVED) == 0) {
+#else
 		if (altq->qname[0] == 0) {
+#endif
 			/* attach the discipline */
 			error = altq_pfattach(altq);
 			if (error == 0 && pf_altq_running)
@@ -857,7 +872,12 @@ pf_commit_altq(u_int32_t ticket)
 	/* Purge the old altq list */
 	while ((altq = TAILQ_FIRST(pf_altqs_inactive)) != NULL) {
 		TAILQ_REMOVE(pf_altqs_inactive, altq, entries);
+#ifdef __FreeBSD__
+		if (altq->qname[0] == 0 &&
+		    (altq->local_flags & PFALTQ_FLAG_IF_REMOVED) == 0) {
+#else
 		if (altq->qname[0] == 0) {
+#endif
 			/* detach and destroy the discipline */
 			if (pf_altq_running)
 				error = pf_disable_altq(altq);
@@ -943,6 +963,76 @@ pf_disable_altq(struct pf_altq *altq)
 
 	return (error);
 }
+
+#ifdef __FreeBSD__
+void
+pf_altq_ifnet_event(struct ifnet *ifp, int remove)
+{
+	struct ifnet		*ifp1;
+	struct pf_altq		*a1, *a2, *a3;
+	u_int32_t		 ticket;
+	int			 error = 0;
+
+	/* Interrupt userland queue modifications */
+	if (altqs_inactive_open)
+		pf_rollback_altq(ticket_altqs_inactive);
+
+	/* Start new altq ruleset */
+	if (pf_begin_altq(&ticket))
+		return;
+
+	/* Copy the current active set */
+	TAILQ_FOREACH(a1, pf_altqs_active, entries) {
+		a2 = pool_get(&pf_altq_pl, PR_NOWAIT);
+		if (a2 == NULL) {
+			error = ENOMEM;
+			break;
+		}
+		bcopy(a1, a2, sizeof(struct pf_altq));
+
+		if (a2->qname[0] != 0) {
+			if ((a2->qid = pf_qname2qid(a2->qname)) == 0) {
+				error = EBUSY;
+				pool_put(&pf_altq_pl, a2);
+				break;
+			}
+			a2->altq_disc = NULL;
+			TAILQ_FOREACH(a3, pf_altqs_inactive, entries) {
+				if (strncmp(a3->ifname, a2->ifname,
+				    IFNAMSIZ) == 0 && a3->qname[0] == 0) {
+					a2->altq_disc = a3->altq_disc;
+					break;
+				}
+			}
+		}
+		/* Deactivate the interface in question */
+		a2->local_flags &= ~PFALTQ_FLAG_IF_REMOVED;
+		if ((ifp1 = ifunit(a2->ifname)) == NULL ||
+		    (remove && ifp1 == ifp)) {
+			a2->local_flags |= PFALTQ_FLAG_IF_REMOVED;
+		} else {
+			PF_UNLOCK();
+			error = altq_add(a2);
+			PF_LOCK();
+
+			if (ticket != ticket_altqs_inactive)
+				error = EBUSY;
+
+			if (error) {
+				pool_put(&pf_altq_pl, a2);
+				break;
+			}
+		}
+
+		TAILQ_INSERT_TAIL(pf_altqs_inactive, a2, entries);
+	}
+
+	if (error != 0)
+		pf_rollback_altq(ticket);
+	else
+		pf_commit_altq(ticket);
+}
+#endif
 #endif /* ALTQ */
 
 int
@@ -2273,7 +2363,12 @@ pfioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
 
 		/* enable all altq interfaces on active list */
 		TAILQ_FOREACH(altq, pf_altqs_active, entries) {
+#ifdef __FreeBSD__
+			if (altq->qname[0] == 0 && (altq->local_flags &
+			    PFALTQ_FLAG_IF_REMOVED) == 0) {
+#else
 			if (altq->qname[0] == 0) {
+#endif
 				error = pf_enable_altq(altq);
 				if (error != 0)
 					break;
@@ -2290,7 +2385,12 @@ pfioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
 
 		/* disable all altq interfaces on active list */
 		TAILQ_FOREACH(altq, pf_altqs_active, entries) {
+#ifdef __FreeBSD__
+			if (altq->qname[0] == 0 && (altq->local_flags &
+			    PFALTQ_FLAG_IF_REMOVED) == 0) {
+#else
 			if (altq->qname[0] == 0) {
+#endif
 				error = pf_disable_altq(altq);
 				if (error != 0)
 					break;
@@ -2316,6 +2416,9 @@ pfioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
 			break;
 		}
 		bcopy(&pa->altq, altq, sizeof(struct pf_altq));
+#ifdef __FreeBSD__
+		altq->local_flags = 0;
+#endif
 
 		/*
 		 * if this is for a queue, find the discipline and
@@ -2327,6 +2430,7 @@ pfioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
 				pool_put(&pf_altq_pl, altq);
 				break;
 			}
+			altq->altq_disc = NULL;
 			TAILQ_FOREACH(a, pf_altqs_inactive, entries) {
 				if (strncmp(a->ifname, altq->ifname,
 				    IFNAMSIZ) == 0 && a->qname[0] == 0) {
@@ -2337,11 +2441,17 @@ pfioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
 		}
 
 #ifdef __FreeBSD__
-		PF_UNLOCK();
+		struct ifnet *ifp;
+
+		if ((ifp = ifunit(altq->ifname)) == NULL) {
+			altq->local_flags |= PFALTQ_FLAG_IF_REMOVED;
+		} else {
+			PF_UNLOCK();
 #endif		
 		error = altq_add(altq);
 #ifdef __FreeBSD__
-		PF_LOCK();
+			PF_LOCK();
+		}
 #endif
 		if (error) {
 			pool_put(&pf_altq_pl, altq);
@@ -2414,6 +2524,10 @@ pfioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p)
 			break;
 		}
 #ifdef __FreeBSD__
+		if ((altq->local_flags & PFALTQ_FLAG_IF_REMOVED) != 0) {
+			error = ENXIO;
+			break;
+		}
 		PF_UNLOCK();
 #endif
 		error = altq_getqstats(altq, pq->buf, &nbytes);
diff --git a/sys/contrib/pf/net/pfvar.h b/sys/contrib/pf/net/pfvar.h
index 6c5c23a..bd75bfc 100644
--- a/sys/contrib/pf/net/pfvar.h
+++ b/sys/contrib/pf/net/pfvar.h
@@ -1247,6 +1247,10 @@ struct pf_altq {
 	u_int32_t		 parent_qid;	/* parent queue id */
 	u_int32_t		 bandwidth;	/* queue bandwidth */
 	u_int8_t		 priority;	/* priority */
+#ifdef __FreeBSD__
+	u_int8_t		 local_flags;	/* dynamic interface */
+#define	PFALTQ_FLAG_IF_REMOVED		0x01
+#endif
 	u_int16_t		 qlimit;	/* queue size limit */
 	u_int16_t		 flags;		/* misc flags */
 	union {
@@ -1574,6 +1578,9 @@ extern void			 pf_tbladdr_remove(struct pf_addr_wrap *);
 extern void			 pf_tbladdr_copyout(struct pf_addr_wrap *);
 extern void			 pf_calc_skip_steps(struct pf_rulequeue *);
 #ifdef __FreeBSD__
+#ifdef ALTQ
+extern void			 pf_altq_ifnet_event(struct ifnet *, int);
+#endif
 extern uma_zone_t		 pf_src_tree_pl, pf_rule_pl;
 extern uma_zone_t		 pf_state_pl, pf_altq_pl, pf_pooladdr_pl;
 extern uma_zone_t		 pfr_ktable_pl, pfr_kentry_pl, pfr_kentry_pl2;