Bonding updates from bonding driver sourceforge

project.

2 files changed, 131 insertions, 66 deletions

diff --git a/drivers/net/bonding.c b/drivers/net/bonding.c
index be6526457..e9736dc3c 100644
--- a/drivers/net/bonding.c
+++ b/drivers/net/bonding.c
@@ -153,6 +153,14 @@
  *
  * 2001/10/23 - Takao Indoh <indou dot takao at jp dot fujitsu dot com>
  *     - Various memory leak fixes
+ *
+ * 2001/11/5 - Mark Huth <mark dot huth at mvista dot com>
+ *     - Don't take rtnl lock in bond_mii_monitor as it deadlocks under 
+ *       certain hotswap conditions.  
+ *       Note:  this same change may be required in bond_arp_monitor ???
+ *     - Remove possibility of calling bond_sethwaddr with NULL slave_dev ptr 
+ *     - Handle hot swap ethernet interface deregistration events to remove
+ *       kernel oops following hot swap of enslaved interface
  */
 
 #include <linux/config.h>
@@ -256,6 +264,7 @@ static void bond_set_slave_inactive_flags(slave_t *slave);
 static void bond_set_slave_active_flags(slave_t *slave);
 static int bond_enslave(struct net_device *master, struct net_device *slave);
 static int bond_release(struct net_device *master, struct net_device *slave);
+static int bond_release_all(struct net_device *master);
 static int bond_sethwaddr(struct net_device *master, struct net_device *slave);
 
 /*
@@ -371,10 +380,13 @@ static u16 bond_check_dev_link(struct net_device *dev)
 static u16 bond_check_mii_link(bonding_t *bond)
 {
 	int has_active_interface = 0;
+	unsigned long flags;
 
+	read_lock_irqsave(&bond->lock, flags);
 	read_lock(&bond->ptrlock);
 	has_active_interface = (bond->current_slave != NULL);
 	read_unlock(&bond->ptrlock);
+	read_unlock_irqrestore(&bond->lock, flags);
 
 	return (has_active_interface ? MII_LINK_READY : 0);
 }
@@ -406,7 +418,6 @@ static int bond_open(struct net_device *dev)
 static int bond_close(struct net_device *master)
 {
 	bonding_t *bond = (struct bonding *) master->priv;
-	slave_t *slave;
 	unsigned long flags;
 
 	write_lock_irqsave(&bond->lock, flags);
@@ -417,13 +428,11 @@ static int bond_close(struct net_device *master)
 	if (arp_interval> 0) {  /* arp interval, in milliseconds. */
 		del_timer(&bond->arp_timer);
 	}
-	/* We need to unlock this because bond_release will re-lock it */
-	write_unlock_irqrestore(&bond->lock, flags);
 
 	/* Release the bonded slaves */
-	while ((slave = bond->prev) != (slave_t *)bond) {
-		bond_release(master, slave->dev);
-	}
+	bond_release_all(master);
+
+	write_unlock_irqrestore(&bond->lock, flags);
 
 	MOD_DEC_USE_COUNT;
 	return 0;
@@ -865,6 +874,49 @@ static int bond_release(struct net_device *master, struct net_device *slave)
 	return -EINVAL;
 }
 
+/* 
+ * This function releases all slaves.
+ * Warning: must put write-locks around the call to this function.
+ */
+static int bond_release_all(struct net_device *master)
+{
+	bonding_t *bond;
+	slave_t *our_slave;
+	struct net_device *slave_dev;
+
+	if (master == NULL)  {
+		return -ENODEV;
+	}
+
+	if (master->flags & IFF_SLAVE) {
+		return -EINVAL;
+	}
+
+	bond = (struct bonding *) master->priv;
+	bond->current_slave = NULL;
+
+	while ((our_slave = bond->prev) != (slave_t *)bond) {
+		slave_dev = our_slave->dev;
+		bond->prev = our_slave->prev;
+
+		kfree(our_slave);
+
+		netdev_set_master(slave_dev, NULL);
+
+		/* only restore its RUNNING flag if monitoring set it down */
+		if (slave_dev->flags & IFF_UP)
+			slave_dev->flags |= IFF_RUNNING;
+
+		if (slave_dev->flags & IFF_NOARP)
+			dev_close(slave_dev);
+	}
+	bond->next = (slave_t *)bond;
+	bond->slave_cnt = 0;
+	printk (KERN_INFO "%s: releases all slaves\n", master->name);
+
+	return 0;
+}
+
 /* this function is called regularly to monitor each slave's link. */
 static void bond_mii_monitor(struct net_device *master)
 {
@@ -875,14 +927,6 @@ static void bond_mii_monitor(struct net_device *master)
 
 	read_lock_irqsave(&bond->lock, flags);
 
-	if (rtnl_shlock_nowait()) {
-		goto monitor_out;
-	}
-
-	if (rtnl_exlock_nowait()) {
-		rtnl_shunlock();
-		goto monitor_out;
-	}
 	/* we will try to read the link status of each of our slaves, and
 	 * set their IFF_RUNNING flag appropriately. For each slave not
 	 * supporting MII status, we won't do anything so that a user-space
@@ -1056,9 +1100,10 @@ static void bond_mii_monitor(struct net_device *master)
 		} /* end of switch */
 	} /* end of while */
 
-	/* if there's no active interface and we discovered that one
-	   of the slaves could be activated earlier, so we do it.
-	*/
+	/* 
+	 * if there's no active interface and we discovered that one
+	 * of the slaves could be activated earlier, so we do it.
+	 */
 	read_lock(&bond->ptrlock);
 	oldcurrent = bond->current_slave;
 	read_unlock(&bond->ptrlock);
@@ -1096,9 +1141,6 @@ static void bond_mii_monitor(struct net_device *master)
 		}
 	}
 
-	rtnl_exunlock();
-	rtnl_shunlock();
-monitor_out:
 	read_unlock_irqrestore(&bond->lock, flags);
 	/* re-arm the timer */
 	mod_timer(&bond->mii_timer, jiffies + (miimon * HZ / 1000));
@@ -1127,17 +1169,17 @@ static void bond_arp_monitor(struct net_device *master)
 
 	if (!IS_UP(master)) {
 		mod_timer(&bond->arp_timer, next_timer);
-		goto monitor_out;
+		goto arp_monitor_out;
 	}
 
 
 	if (rtnl_shlock_nowait()) {
-		goto monitor_out;
+		goto arp_monitor_out;
 	}
 
 	if (rtnl_exlock_nowait()) {
 		rtnl_shunlock();
-		goto monitor_out;
+		goto arp_monitor_out;
 	}
 
 	/* see if any of the previous devices are up now (i.e. they have seen a 
@@ -1242,7 +1284,9 @@ static void bond_arp_monitor(struct net_device *master)
 	 * an arp on all of the interfaces 
 	 */
 
+	read_lock(&bond->ptrlock);
 	if (bond->current_slave == NULL) { 
+		read_unlock(&bond->ptrlock);
 		slave = (slave_t *)bond;
 		while ((slave = slave->prev) != (slave_t *)bond)   {
 			arp_send(ARPOP_REQUEST, ETH_P_ARP, arp_target, 
@@ -1250,11 +1294,14 @@ static void bond_arp_monitor(struct net_device *master)
 				 slave->dev->dev_addr, arp_target_hw_addr); 
 		}
 	}
+	else {
+		read_unlock(&bond->ptrlock);
+	}
 
 	rtnl_exunlock();
 	rtnl_shunlock();
 
-monitor_out:
+arp_monitor_out:
 	read_unlock_irqrestore(&bond->lock, flags);
 
 	/* re-arm the timer */
@@ -1366,16 +1413,17 @@ static int bond_info_query(struct net_device *master, struct ifbond *info)
 {
 	bonding_t *bond = (struct bonding *) master->priv;
 	slave_t *slave;
+	unsigned long flags;
 
 	info->bond_mode = mode;
 	info->num_slaves = 0;
 	info->miimon = miimon;
 
-	read_lock(&bond->ptrlock);
+	read_lock_irqsave(&bond->lock, flags);
 	for (slave = bond->prev; slave!=(slave_t *)bond; slave = slave->prev) {
 		info->num_slaves++;
 	}
-	read_unlock(&bond->ptrlock);
+	read_unlock_irqrestore(&bond->lock, flags);
 
 	return 0;
 }
@@ -1386,27 +1434,28 @@ static int bond_slave_info_query(struct net_device *master,
 	bonding_t *bond = (struct bonding *) master->priv;
 	slave_t *slave;
 	int cur_ndx = 0;
+	unsigned long flags;
 
 	if (info->slave_id < 0) {
 		return -ENODEV;
 	}
 
-	read_lock(&bond->ptrlock);
+	read_lock_irqsave(&bond->lock, flags);
 	for (slave = bond->prev; 
 		 slave != (slave_t *)bond && cur_ndx < info->slave_id; 
 		 slave = slave->prev) {
 		cur_ndx++;
 	}
+	read_unlock_irqrestore(&bond->lock, flags);
+
 	if (cur_ndx == info->slave_id) {
 		strcpy(info->slave_name, slave->dev->name);
 		info->link = slave->link;
 		info->state = slave->state;
 		info->link_failure_count = slave->link_failure_count;
 	} else {
-		read_unlock(&bond->ptrlock);
 		return -ENODEV;
 	}
-	read_unlock(&bond->ptrlock);
 
 	return 0;
 }
@@ -1479,40 +1528,40 @@ static int bond_ioctl(struct net_device *master_dev, struct ifreq *ifr, int cmd)
 	}
 
 	slave_dev = dev_get_by_name(ifr->ifr_slave);
+
 #ifdef BONDING_DEBUG
 	printk(KERN_INFO "slave_dev=%x: \n", (unsigned int)slave_dev);
 	printk(KERN_INFO "slave_dev->name=%s: \n", slave_dev->name);
 #endif
-	switch (cmd) {
-	case BOND_ENSLAVE_OLD:
-	case SIOCBONDENSLAVE:		
-		ret = bond_enslave(master_dev, slave_dev);
-		break;
-	case BOND_RELEASE_OLD:			
-	case SIOCBONDRELEASE:	
-		ret = bond_release(master_dev, slave_dev); 
-		break;
-	case BOND_SETHWADDR_OLD:
-	case SIOCBONDSETHWADDR:	
-		ret = bond_sethwaddr(master_dev, slave_dev);
-		break;
-	case BOND_CHANGE_ACTIVE_OLD:
-	case SIOCBONDCHANGEACTIVE:
-		if (mode == BOND_MODE_ACTIVEBACKUP) {
-			ret = bond_change_active(master_dev, slave_dev);
-		}
-		else {
-			ret = -EINVAL;
-		}
-		break;
-	default:
-		ret = -EOPNOTSUPP;
-	}
 
-	if (slave_dev) {
-		/*
-		 * Clear the module reference that was added by dev_get_by_name
-		 */
+	if (slave_dev == NULL) {
+		ret = -ENODEV;
+	} else {
+		switch (cmd) {
+		case BOND_ENSLAVE_OLD:
+		case SIOCBONDENSLAVE:		
+			ret = bond_enslave(master_dev, slave_dev);
+			break;
+		case BOND_RELEASE_OLD:			
+		case SIOCBONDRELEASE:	
+			ret = bond_release(master_dev, slave_dev); 
+			break;
+		case BOND_SETHWADDR_OLD:
+		case SIOCBONDSETHWADDR:	
+			ret = bond_sethwaddr(master_dev, slave_dev);
+			break;
+		case BOND_CHANGE_ACTIVE_OLD:
+		case SIOCBONDCHANGEACTIVE:
+			if (mode == BOND_MODE_ACTIVEBACKUP) {
+				ret = bond_change_active(master_dev, slave_dev);
+			}
+			else {
+				ret = -EINVAL;
+			}
+			break;
+		default:
+			ret = -EOPNOTSUPP;
+		}
 		dev_put(slave_dev);
 	}
 	return ret;
@@ -1592,13 +1641,11 @@ static int bond_xmit_xor(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	read_lock_irqsave(&bond->lock, flags);
-	read_lock(&bond->ptrlock);
 	slave = bond->prev;
 
 	/* we're at the root, get the first slave */
 	if ((slave == NULL) || (slave->dev == NULL)) { 
 		/* no suitable interface, frame not sent */
-		read_unlock(&bond->ptrlock);
 		dev_kfree_skb(skb);
 		read_unlock_irqrestore(&bond->lock, flags);
 		return 0;
@@ -1606,8 +1653,6 @@ static int bond_xmit_xor(struct sk_buff *skb, struct net_device *dev)
 
 	slave_no = (data->h_dest[5]^slave->dev->dev_addr[5]) % bond->slave_cnt;
 
-	read_unlock(&bond->ptrlock);
-
 	while ( (slave_no > 0) && (slave != (slave_t *)bond) ) {
 		slave = slave->prev;
 		slave_no--;
@@ -1748,6 +1793,7 @@ static int bond_get_info(char *buf, char **start, off_t offset, int length)
 	off_t begin = 0;
 	u16 link;
 	slave_t *slave = NULL;
+	unsigned long flags;
 
 	while (bond != NULL) {
 		/*
@@ -1756,17 +1802,19 @@ static int bond_get_info(char *buf, char **start, off_t offset, int length)
 		 */
 		link = bond_check_mii_link(bond);
 
-		read_lock(&bond->ptrlock);
-
 		len += sprintf(buf + len, "Bonding Mode: ");
 		len += sprintf(buf + len, "%s\n", mode ? "active-backup" : "load balancing");
 
 		if (mode == BOND_MODE_ACTIVEBACKUP) {
+			read_lock_irqsave(&bond->lock, flags);
+			read_lock(&bond->ptrlock);
 			if (bond->current_slave != NULL) {
 				len += sprintf(buf + len, 
 					"Currently Active Slave: %s\n", 
 					bond->current_slave->dev->name);
 			}
+			read_unlock(&bond->ptrlock);
+			read_unlock_irqrestore(&bond->lock, flags);
 		}
 
 		len += sprintf(buf + len, "MII Status: ");
@@ -1777,6 +1825,7 @@ static int bond_get_info(char *buf, char **start, off_t offset, int length)
 		len += sprintf(buf + len, "Up Delay (ms): %d\n", updelay);
 		len += sprintf(buf + len, "Down Delay (ms): %d\n", downdelay);
 
+		read_lock_irqsave(&bond->lock, flags);
 		for (slave = bond->prev; slave != (slave_t *)bond; 
 		     slave = slave->prev) {
 			len += sprintf(buf + len, "\nSlave Interface: %s\n", slave->dev->name);
@@ -1789,6 +1838,7 @@ static int bond_get_info(char *buf, char **start, off_t offset, int length)
 			len += sprintf(buf + len, "Link Failure Count: %d\n", 
 				slave->link_failure_count);
 		}
+		read_unlock_irqrestore(&bond->lock, flags);
 
 		/*
 		 * Figure out the calcs for the /proc/net interface
@@ -1802,7 +1852,6 @@ static int bond_get_info(char *buf, char **start, off_t offset, int length)
 			len = 0;
 		}
 
-		read_unlock(&bond->ptrlock);
 
 		bond = bond->next_bond;
 	}
@@ -1843,7 +1892,14 @@ static int bond_event(struct notifier_block *this, unsigned long event,
 			default:
 				return NOTIFY_DONE;
 			}
-		} 
+		} else if (this_bond->device == event_dev->master) {
+			switch (event) {
+			case NETDEV_UNREGISTER:
+				bond_release(this_bond->device, event_dev);
+				break;
+			}
+			return NOTIFY_DONE;
+		}
 		this_bond = this_bond->next_bond;
 	}
 	return NOTIFY_DONE;
diff --git a/include/linux/if_bonding.h b/include/linux/if_bonding.h
index d719560dd..97d490fd8 100644
--- a/include/linux/if_bonding.h
+++ b/include/linux/if_bonding.h
@@ -79,6 +79,15 @@ typedef struct slave {
 	u32 link_failure_count;
 } slave_t;
 
+/*
+ * Here are the locking policies for the two bonding locks:
+ *
+ * 1) Get bond->lock when reading/writing slave list.
+ * 2) Get bond->ptrlock when reading/writing bond->current_slave.
+ *    (It is unnecessary when the write-lock is put with bond->lock.)
+ * 3) When we lock with bond->ptrlock, we must lock with bond->lock
+ *    beforehand.
+ */
 typedef struct bonding {
 	slave_t *next;
 	slave_t *prev;