3 files changed, 126 insertions, 61 deletions

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index f04f3625e944..a2ef3f72de88 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -181,7 +181,7 @@ static inline int __agg_has_partner(struct aggregator *agg)
  */
 static inline void __disable_port(struct port *port)
 {
-	bond_set_slave_inactive_flags(port->slave);
+	bond_set_slave_inactive_flags(port->slave, BOND_SLAVE_NOTIFY_LATER);
 }
 
 /**
@@ -193,7 +193,7 @@ static inline void __enable_port(struct port *port)
 	struct slave *slave = port->slave;
 
 	if ((slave->link == BOND_LINK_UP) && IS_UP(slave->dev))
-		bond_set_slave_active_flags(slave);
+		bond_set_slave_active_flags(slave, BOND_SLAVE_NOTIFY_LATER);
 }
 
 /**
@@ -2063,6 +2063,7 @@ void bond_3ad_state_machine_handler(struct work_struct *work)
 	struct list_head *iter;
 	struct slave *slave;
 	struct port *port;
+	bool should_notify_rtnl = BOND_SLAVE_NOTIFY_LATER;
 
 	read_lock(&bond->lock);
 	rcu_read_lock();
@@ -2120,8 +2121,19 @@ void bond_3ad_state_machine_handler(struct work_struct *work)
 	}
 
 re_arm:
+	bond_for_each_slave_rcu(bond, slave, iter) {
+		if (slave->should_notify) {
+			should_notify_rtnl = BOND_SLAVE_NOTIFY_NOW;
+			break;
+		}
+	}
 	rcu_read_unlock();
 	read_unlock(&bond->lock);
+
+	if (should_notify_rtnl && rtnl_trylock()) {
+		bond_slave_state_notify(bond);
+		rtnl_unlock();
+	}
 	queue_delayed_work(bond->wq, &bond->ad_work, ad_delta_in_ticks);
 }
 
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 12861e37d526..730d72c706c9 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -829,21 +829,25 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
 	if (bond_is_lb(bond)) {
 		bond_alb_handle_active_change(bond, new_active);
 		if (old_active)
-			bond_set_slave_inactive_flags(old_active);
+			bond_set_slave_inactive_flags(old_active,
+						      BOND_SLAVE_NOTIFY_NOW);
 		if (new_active)
-			bond_set_slave_active_flags(new_active);
+			bond_set_slave_active_flags(new_active,
+						    BOND_SLAVE_NOTIFY_NOW);
 	} else {
 		rcu_assign_pointer(bond->curr_active_slave, new_active);
 	}
 
 	if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
 		if (old_active)
-			bond_set_slave_inactive_flags(old_active);
+			bond_set_slave_inactive_flags(old_active,
+						      BOND_SLAVE_NOTIFY_NOW);
 
 		if (new_active) {
 			bool should_notify_peers = false;
 
-			bond_set_slave_active_flags(new_active);
+			bond_set_slave_active_flags(new_active,
+						    BOND_SLAVE_NOTIFY_NOW);
 
 			if (bond->params.fail_over_mac)
 				bond_do_fail_over_mac(bond, new_active,
@@ -1182,6 +1186,11 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 		return -EBUSY;
 	}
 
+	if (bond_dev == slave_dev) {
+		pr_err("%s: cannot enslave bond to itself.\n", bond_dev->name);
+		return -EPERM;
+	}
+
 	/* vlan challenged mutual exclusion */
 	/* no need to lock since we're protected by rtnl_lock */
 	if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {
@@ -1451,14 +1460,15 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 
 	switch (bond->params.mode) {
 	case BOND_MODE_ACTIVEBACKUP:
-		bond_set_slave_inactive_flags(new_slave);
+		bond_set_slave_inactive_flags(new_slave,
+					      BOND_SLAVE_NOTIFY_NOW);
 		break;
 	case BOND_MODE_8023AD:
 		/* in 802.3ad mode, the internal mechanism
 		 * will activate the slaves in the selected
 		 * aggregator
 		 */
-		bond_set_slave_inactive_flags(new_slave);
+		bond_set_slave_inactive_flags(new_slave, BOND_SLAVE_NOTIFY_NOW);
 		/* if this is the first slave */
 		if (!prev_slave) {
 			SLAVE_AD_INFO(new_slave).id = 1;
@@ -1476,7 +1486,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 	case BOND_MODE_TLB:
 	case BOND_MODE_ALB:
 		bond_set_active_slave(new_slave);
-		bond_set_slave_inactive_flags(new_slave);
+		bond_set_slave_inactive_flags(new_slave, BOND_SLAVE_NOTIFY_NOW);
 		break;
 	default:
 		pr_debug("This slave is always active in trunk mode\n");
@@ -1641,9 +1651,6 @@ static int __bond_release_one(struct net_device *bond_dev,
 		return -EINVAL;
 	}
 
-	/* release the slave from its bond */
-	bond->slave_cnt--;
-
 	bond_sysfs_slave_del(slave);
 
 	bond_upper_dev_unlink(bond_dev, slave_dev);
@@ -1725,6 +1732,7 @@ static int __bond_release_one(struct net_device *bond_dev,
 
 	unblock_netpoll_tx();
 	synchronize_rcu();
+	bond->slave_cnt--;
 
 	if (!bond_has_slaves(bond)) {
 		call_netdevice_notifiers(NETDEV_CHANGEADDR, bond->dev);
@@ -1998,7 +2006,8 @@ static void bond_miimon_commit(struct bonding *bond)
 
 			if (bond->params.mode == BOND_MODE_ACTIVEBACKUP ||
 			    bond->params.mode == BOND_MODE_8023AD)
-				bond_set_slave_inactive_flags(slave);
+				bond_set_slave_inactive_flags(slave,
+							      BOND_SLAVE_NOTIFY_NOW);
 
 			pr_info("%s: link status definitely down for interface %s, disabling it\n",
 				bond->dev->name, slave->dev->name);
@@ -2553,7 +2562,8 @@ static void bond_ab_arp_commit(struct bonding *bond)
 				slave->link = BOND_LINK_UP;
 				if (bond->current_arp_slave) {
 					bond_set_slave_inactive_flags(
-						bond->current_arp_slave);
+						bond->current_arp_slave,
+						BOND_SLAVE_NOTIFY_NOW);
 					bond->current_arp_slave = NULL;
 				}
 
@@ -2573,7 +2583,8 @@ static void bond_ab_arp_commit(struct bonding *bond)
 				slave->link_failure_count++;
 
 			slave->link = BOND_LINK_DOWN;
-			bond_set_slave_inactive_flags(slave);
+			bond_set_slave_inactive_flags(slave,
+						      BOND_SLAVE_NOTIFY_NOW);
 
 			pr_info("%s: link status definitely down for interface %s, disabling it\n",
 				bond->dev->name, slave->dev->name);
@@ -2606,17 +2617,17 @@ do_failover:
 
 /*
  * Send ARP probes for active-backup mode ARP monitor.
+ *
+ * Called with rcu_read_lock hold.
  */
 static bool bond_ab_arp_probe(struct bonding *bond)
 {
 	struct slave *slave, *before = NULL, *new_slave = NULL,
-		     *curr_arp_slave, *curr_active_slave;
+		     *curr_arp_slave = rcu_dereference(bond->current_arp_slave),
+		     *curr_active_slave = rcu_dereference(bond->curr_active_slave);
 	struct list_head *iter;
 	bool found = false;
-
-	rcu_read_lock();
-	curr_arp_slave = rcu_dereference(bond->current_arp_slave);
-	curr_active_slave = rcu_dereference(bond->curr_active_slave);
+	bool should_notify_rtnl = BOND_SLAVE_NOTIFY_LATER;
 
 	if (curr_arp_slave && curr_active_slave)
 		pr_info("PROBE: c_arp %s && cas %s BAD\n",
@@ -2625,32 +2636,23 @@ static bool bond_ab_arp_probe(struct bonding *bond)
 
 	if (curr_active_slave) {
 		bond_arp_send_all(bond, curr_active_slave);
-		rcu_read_unlock();
-		return true;
+		return should_notify_rtnl;
 	}
-	rcu_read_unlock();
 
 	/* if we don't have a curr_active_slave, search for the next available
 	 * backup slave from the current_arp_slave and make it the candidate
 	 * for becoming the curr_active_slave
 	 */
 
-	if (!rtnl_trylock())
-		return false;
-	/* curr_arp_slave might have gone away */
-	curr_arp_slave = ACCESS_ONCE(bond->current_arp_slave);
-
 	if (!curr_arp_slave) {
-		curr_arp_slave = bond_first_slave(bond);
-		if (!curr_arp_slave) {
-			rtnl_unlock();
-			return true;
-		}
+		curr_arp_slave = bond_first_slave_rcu(bond);
+		if (!curr_arp_slave)
+			return should_notify_rtnl;
 	}
 
-	bond_set_slave_inactive_flags(curr_arp_slave);
+	bond_set_slave_inactive_flags(curr_arp_slave, BOND_SLAVE_NOTIFY_LATER);
 
-	bond_for_each_slave(bond, slave, iter) {
+	bond_for_each_slave_rcu(bond, slave, iter) {
 		if (!found && !before && IS_UP(slave->dev))
 			before = slave;
 
@@ -2668,7 +2670,8 @@ static bool bond_ab_arp_probe(struct bonding *bond)
 			if (slave->link_failure_count < UINT_MAX)
 				slave->link_failure_count++;
 
-			bond_set_slave_inactive_flags(slave);
+			bond_set_slave_inactive_flags(slave,
+						      BOND_SLAVE_NOTIFY_LATER);
 
 			pr_info("%s: backup interface %s is now down\n",
 				bond->dev->name, slave->dev->name);
@@ -2680,26 +2683,31 @@ static bool bond_ab_arp_probe(struct bonding *bond)
 	if (!new_slave && before)
 		new_slave = before;
 
-	if (!new_slave) {
-		rtnl_unlock();
-		return true;
-	}
+	if (!new_slave)
+		goto check_state;
 
 	new_slave->link = BOND_LINK_BACK;
-	bond_set_slave_active_flags(new_slave);
+	bond_set_slave_active_flags(new_slave, BOND_SLAVE_NOTIFY_LATER);
 	bond_arp_send_all(bond, new_slave);
 	new_slave->last_link_up = jiffies;
 	rcu_assign_pointer(bond->current_arp_slave, new_slave);
-	rtnl_unlock();
 
-	return true;
+check_state:
+	bond_for_each_slave_rcu(bond, slave, iter) {
+		if (slave->should_notify) {
+			should_notify_rtnl = BOND_SLAVE_NOTIFY_NOW;
+			break;
+		}
+	}
+	return should_notify_rtnl;
 }
 
 static void bond_activebackup_arp_mon(struct work_struct *work)
 {
 	struct bonding *bond = container_of(work, struct bonding,
 					    arp_work.work);
-	bool should_notify_peers = false, should_commit = false;
+	bool should_notify_peers = false;
+	bool should_notify_rtnl = false;
 	int delta_in_ticks;
 
 	delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
@@ -2708,11 +2716,12 @@ static void bond_activebackup_arp_mon(struct work_struct *work)
 		goto re_arm;
 
 	rcu_read_lock();
+
 	should_notify_peers = bond_should_notify_peers(bond);
-	should_commit = bond_ab_arp_inspect(bond);
-	rcu_read_unlock();
 
-	if (should_commit) {
+	if (bond_ab_arp_inspect(bond)) {
+		rcu_read_unlock();
+
 		/* Race avoidance with bond_close flush of workqueue */
 		if (!rtnl_trylock()) {
 			delta_in_ticks = 1;
@@ -2721,23 +2730,28 @@ static void bond_activebackup_arp_mon(struct work_struct *work)
 		}
 
 		bond_ab_arp_commit(bond);
+
 		rtnl_unlock();
+		rcu_read_lock();
 	}
 
-	if (!bond_ab_arp_probe(bond)) {
-		/* rtnl locking failed, re-arm */
-		delta_in_ticks = 1;
-		should_notify_peers = false;
-	}
+	should_notify_rtnl = bond_ab_arp_probe(bond);
+	rcu_read_unlock();
 
 re_arm:
 	if (bond->params.arp_interval)
 		queue_delayed_work(bond->wq, &bond->arp_work, delta_in_ticks);
 
-	if (should_notify_peers) {
+	if (should_notify_peers || should_notify_rtnl) {
 		if (!rtnl_trylock())
 			return;
-		call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, bond->dev);
+
+		if (should_notify_peers)
+			call_netdevice_notifiers(NETDEV_NOTIFY_PEERS,
+						 bond->dev);
+		if (should_notify_rtnl)
+			bond_slave_state_notify(bond);
+
 		rtnl_unlock();
 	}
 }
@@ -3036,9 +3050,11 @@ static int bond_open(struct net_device *bond_dev)
 		bond_for_each_slave(bond, slave, iter) {
 			if ((bond->params.mode == BOND_MODE_ACTIVEBACKUP)
 				&& (slave != bond->curr_active_slave)) {
-				bond_set_slave_inactive_flags(slave);
+				bond_set_slave_inactive_flags(slave,
+							      BOND_SLAVE_NOTIFY_NOW);
 			} else {
-				bond_set_slave_active_flags(slave);
+				bond_set_slave_active_flags(slave,
+							    BOND_SLAVE_NOTIFY_NOW);
 			}
 		}
 		read_unlock(&bond->curr_slave_lock);
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 430362891d0d..b7127a1ba2c9 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -196,7 +196,8 @@ struct slave {
 	s8     new_link;
 	u8     backup:1,   /* indicates backup slave. Value corresponds with
 			      BOND_STATE_ACTIVE and BOND_STATE_BACKUP */
-	       inactive:1; /* indicates inactive slave */
+	       inactive:1, /* indicates inactive slave */
+	       should_notify:1; /* indicateds whether the state changed */
 	u8     duplex;
 	u32    original_mtu;
 	u32    link_failure_count;
@@ -304,6 +305,24 @@ static inline void bond_set_backup_slave(struct slave *slave)
 	}
 }
 
+static inline void bond_set_slave_state(struct slave *slave,
+					int slave_state, bool notify)
+{
+	if (slave->backup == slave_state)
+		return;
+
+	slave->backup = slave_state;
+	if (notify) {
+		rtmsg_ifinfo(RTM_NEWLINK, slave->dev, 0, GFP_KERNEL);
+		slave->should_notify = 0;
+	} else {
+		if (slave->should_notify)
+			slave->should_notify = 0;
+		else
+			slave->should_notify = 1;
+	}
+}
+
 static inline void bond_slave_state_change(struct bonding *bond)
 {
 	struct list_head *iter;
@@ -317,6 +336,19 @@ static inline void bond_slave_state_change(struct bonding *bond)
 	}
 }
 
+static inline void bond_slave_state_notify(struct bonding *bond)
+{
+	struct list_head *iter;
+	struct slave *tmp;
+
+	bond_for_each_slave(bond, tmp, iter) {
+		if (tmp->should_notify) {
+			rtmsg_ifinfo(RTM_NEWLINK, tmp->dev, 0, GFP_KERNEL);
+			tmp->should_notify = 0;
+		}
+	}
+}
+
 static inline int bond_slave_state(struct slave *slave)
 {
 	return slave->backup;
@@ -349,6 +381,9 @@ static inline bool bond_is_active_slave(struct slave *slave)
 #define BOND_ARP_FILTER_BACKUP		(BOND_ARP_VALIDATE_BACKUP | \
 					 BOND_ARP_FILTER)
 
+#define BOND_SLAVE_NOTIFY_NOW		true
+#define BOND_SLAVE_NOTIFY_LATER		false
+
 static inline int slave_do_arp_validate(struct bonding *bond,
 					struct slave *slave)
 {
@@ -402,17 +437,19 @@ static inline void bond_netpoll_send_skb(const struct slave *slave,
 }
 #endif
 
-static inline void bond_set_slave_inactive_flags(struct slave *slave)
+static inline void bond_set_slave_inactive_flags(struct slave *slave,
+						 bool notify)
 {
 	if (!bond_is_lb(slave->bond))
-		bond_set_backup_slave(slave);
+		bond_set_slave_state(slave, BOND_STATE_BACKUP, notify);
 	if (!slave->bond->params.all_slaves_active)
 		slave->inactive = 1;
 }
 
-static inline void bond_set_slave_active_flags(struct slave *slave)
+static inline void bond_set_slave_active_flags(struct slave *slave,
+					       bool notify)
 {
-	bond_set_active_slave(slave);
+	bond_set_slave_state(slave, BOND_STATE_ACTIVE, notify);
 	slave->inactive = 0;
 }