]> Pileus Git - ~andy/linux/blobdiff - drivers/net/bonding/bond_main.c
bonding: Add "follow" option to fail_over_mac
[~andy/linux] / drivers / net / bonding / bond_main.c
index 12c71582f4f6adba7e58721d54666a8e634b2078..5b4af3cc2a44231ecae682180abc0e3ac3d77ef2 100644 (file)
@@ -88,6 +88,7 @@
 #define BOND_LINK_ARP_INTERV   0
 
 static int max_bonds   = BOND_DEFAULT_MAX_BONDS;
+static int num_grat_arp = 1;
 static int miimon      = BOND_LINK_MON_INTERV;
 static int updelay     = 0;
 static int downdelay   = 0;
@@ -99,11 +100,13 @@ static char *xmit_hash_policy = NULL;
 static int arp_interval = BOND_LINK_ARP_INTERV;
 static char *arp_ip_target[BOND_MAX_ARP_TARGETS] = { NULL, };
 static char *arp_validate = NULL;
-static int fail_over_mac = 0;
+static char *fail_over_mac = NULL;
 struct bond_params bonding_defaults;
 
 module_param(max_bonds, int, 0);
 MODULE_PARM_DESC(max_bonds, "Max number of bonded devices");
+module_param(num_grat_arp, int, 0644);
+MODULE_PARM_DESC(num_grat_arp, "Number of gratuitous ARP packets to send on failover event");
 module_param(miimon, int, 0);
 MODULE_PARM_DESC(miimon, "Link check interval in milliseconds");
 module_param(updelay, int, 0);
@@ -133,8 +136,8 @@ module_param_array(arp_ip_target, charp, NULL, 0);
 MODULE_PARM_DESC(arp_ip_target, "arp targets in n.n.n.n form");
 module_param(arp_validate, charp, 0);
 MODULE_PARM_DESC(arp_validate, "validate src/dst of ARP probes: none (default), active, backup or all");
-module_param(fail_over_mac, int, 0);
-MODULE_PARM_DESC(fail_over_mac, "For active-backup, do not set all slaves to the same MAC.  0 of off (default), 1 for on.");
+module_param(fail_over_mac, charp, 0);
+MODULE_PARM_DESC(fail_over_mac, "For active-backup, do not set all slaves to the same MAC.  none (default), active or follow");
 
 /*----------------------------- Global variables ----------------------------*/
 
@@ -187,6 +190,13 @@ struct bond_parm_tbl arp_validate_tbl[] = {
 {      NULL,                   -1},
 };
 
+struct bond_parm_tbl fail_over_mac_tbl[] = {
+{      "none",                 BOND_FOM_NONE},
+{      "active",               BOND_FOM_ACTIVE},
+{      "follow",               BOND_FOM_FOLLOW},
+{      NULL,                   -1},
+};
+
 /*-------------------------- Forward declarations ---------------------------*/
 
 static void bond_send_gratuitous_arp(struct bonding *bond);
@@ -261,14 +271,14 @@ static int bond_add_vlan(struct bonding *bond, unsigned short vlan_id)
  */
 static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
 {
-       struct vlan_entry *vlan, *next;
+       struct vlan_entry *vlan;
        int res = -ENODEV;
 
        dprintk("bond: %s, vlan id %d\n", bond->dev->name, vlan_id);
 
        write_lock_bh(&bond->lock);
 
-       list_for_each_entry_safe(vlan, next, &bond->vlan_list, vlan_list) {
+       list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
                if (vlan->vlan_id == vlan_id) {
                        list_del(&vlan->vlan_list);
 
@@ -970,6 +980,82 @@ static void bond_mc_swap(struct bonding *bond, struct slave *new_active, struct
        }
 }
 
+/*
+ * bond_do_fail_over_mac
+ *
+ * Perform special MAC address swapping for fail_over_mac settings
+ *
+ * Called with RTNL, bond->lock for read, curr_slave_lock for write_bh.
+ */
+static void bond_do_fail_over_mac(struct bonding *bond,
+                                 struct slave *new_active,
+                                 struct slave *old_active)
+{
+       u8 tmp_mac[ETH_ALEN];
+       struct sockaddr saddr;
+       int rv;
+
+       switch (bond->params.fail_over_mac) {
+       case BOND_FOM_ACTIVE:
+               if (new_active)
+                       memcpy(bond->dev->dev_addr,  new_active->dev->dev_addr,
+                              new_active->dev->addr_len);
+               break;
+       case BOND_FOM_FOLLOW:
+               /*
+                * if new_active && old_active, swap them
+                * if just old_active, do nothing (going to no active slave)
+                * if just new_active, set new_active to bond's MAC
+                */
+               if (!new_active)
+                       return;
+
+               write_unlock_bh(&bond->curr_slave_lock);
+               read_unlock(&bond->lock);
+
+               if (old_active) {
+                       memcpy(tmp_mac, new_active->dev->dev_addr, ETH_ALEN);
+                       memcpy(saddr.sa_data, old_active->dev->dev_addr,
+                              ETH_ALEN);
+                       saddr.sa_family = new_active->dev->type;
+               } else {
+                       memcpy(saddr.sa_data, bond->dev->dev_addr, ETH_ALEN);
+                       saddr.sa_family = bond->dev->type;
+               }
+
+               rv = dev_set_mac_address(new_active->dev, &saddr);
+               if (rv) {
+                       printk(KERN_ERR DRV_NAME
+                              ": %s: Error %d setting MAC of slave %s\n",
+                              bond->dev->name, -rv, new_active->dev->name);
+                       goto out;
+               }
+
+               if (!old_active)
+                       goto out;
+
+               memcpy(saddr.sa_data, tmp_mac, ETH_ALEN);
+               saddr.sa_family = old_active->dev->type;
+
+               rv = dev_set_mac_address(old_active->dev, &saddr);
+               if (rv)
+                       printk(KERN_ERR DRV_NAME
+                              ": %s: Error %d setting MAC of slave %s\n",
+                              bond->dev->name, -rv, new_active->dev->name);
+out:
+               read_lock(&bond->lock);
+               write_lock_bh(&bond->curr_slave_lock);
+               break;
+       default:
+               printk(KERN_ERR DRV_NAME
+                      ": %s: bond_do_fail_over_mac impossible: bad policy %d\n",
+                      bond->dev->name, bond->params.fail_over_mac);
+               break;
+       }
+
+}
+
+
 /**
  * find_best_interface - select the best available slave to be the active one
  * @bond: our bonding struct
@@ -1037,7 +1123,8 @@ static struct slave *bond_find_best_slave(struct bonding *bond)
  * because it is apparently the best available slave we have, even though its
  * updelay hasn't timed out yet.
  *
- * Warning: Caller must hold curr_slave_lock for writing.
+ * If new_active is not NULL, caller must hold bond->lock for read and
+ * curr_slave_lock for write_bh.
  */
 void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
 {
@@ -1048,6 +1135,8 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
        }
 
        if (new_active) {
+               new_active->jiffies = jiffies;
+
                if (new_active->link == BOND_LINK_BACK) {
                        if (USES_PRIMARY(bond->params.mode)) {
                                printk(KERN_INFO DRV_NAME
@@ -1059,7 +1148,6 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
 
                        new_active->delay = 0;
                        new_active->link = BOND_LINK_UP;
-                       new_active->jiffies = jiffies;
 
                        if (bond->params.mode == BOND_MODE_8023AD) {
                                bond_3ad_handle_link_change(new_active, BOND_LINK_UP);
@@ -1103,20 +1191,21 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
                        bond_set_slave_active_flags(new_active);
                }
 
-               /* when bonding does not set the slave MAC address, the bond MAC
-                * address is the one of the active slave.
-                */
                if (new_active && bond->params.fail_over_mac)
-                       memcpy(bond->dev->dev_addr,  new_active->dev->dev_addr,
-                               new_active->dev->addr_len);
+                       bond_do_fail_over_mac(bond, new_active, old_active);
+
+               bond->send_grat_arp = bond->params.num_grat_arp;
                if (bond->curr_active_slave &&
                        test_bit(__LINK_STATE_LINKWATCH_PENDING,
                                        &bond->curr_active_slave->dev->state)) {
                        dprintk("delaying gratuitous arp on %s\n",
                                bond->curr_active_slave->dev->name);
-                       bond->send_grat_arp = 1;
-               } else
-                       bond_send_gratuitous_arp(bond);
+               } else {
+                       if (bond->send_grat_arp > 0) {
+                               bond_send_gratuitous_arp(bond);
+                               bond->send_grat_arp--;
+                       }
+               }
        }
 }
 
@@ -1129,7 +1218,7 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
  * - The primary_slave has got its link back.
  * - A slave has got its link back and there's no old curr_active_slave.
  *
- * Warning: Caller must hold curr_slave_lock for writing.
+ * Caller must hold bond->lock for read and curr_slave_lock for write_bh.
  */
 void bond_select_active_slave(struct bonding *bond)
 {
@@ -1376,14 +1465,14 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
                        printk(KERN_WARNING DRV_NAME
                               ": %s: Warning: The first slave device "
                               "specified does not support setting the MAC "
-                              "address. Enabling the fail_over_mac option.",
+                              "address. Setting fail_over_mac to active.",
                               bond_dev->name);
-                       bond->params.fail_over_mac = 1;
-               } else if (!bond->params.fail_over_mac) {
+                       bond->params.fail_over_mac = BOND_FOM_ACTIVE;
+               } else if (bond->params.fail_over_mac != BOND_FOM_ACTIVE) {
                        printk(KERN_ERR DRV_NAME
                                ": %s: Error: The slave device specified "
                                "does not support setting the MAC address, "
-                               "but fail_over_mac is not enabled.\n"
+                               "but fail_over_mac is not set to active.\n"
                                , bond_dev->name);
                        res = -EOPNOTSUPP;
                        goto err_undo_flags;
@@ -1490,6 +1579,10 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 
        bond_compute_features(bond);
 
+       write_unlock_bh(&bond->lock);
+
+       read_lock(&bond->lock);
+
        new_slave->last_arp_rx = jiffies;
 
        if (bond->params.miimon && !bond->params.use_carrier) {
@@ -1566,6 +1659,8 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
                }
        }
 
+       write_lock_bh(&bond->curr_slave_lock);
+
        switch (bond->params.mode) {
        case BOND_MODE_ACTIVEBACKUP:
                bond_set_slave_inactive_flags(new_slave);
@@ -1613,9 +1708,11 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
                break;
        } /* switch(bond_mode) */
 
+       write_unlock_bh(&bond->curr_slave_lock);
+
        bond_set_carrier(bond);
 
-       write_unlock_bh(&bond->lock);
+       read_unlock(&bond->lock);
 
        res = bond_create_slave_symlinks(bond_dev, slave_dev);
        if (res)
@@ -1639,6 +1736,10 @@ err_unset_master:
 
 err_restore_mac:
        if (!bond->params.fail_over_mac) {
+               /* XXX TODO - fom follow mode needs to change master's
+                * MAC if this slave's MAC is in use by the bond, or at
+                * least print a warning.
+                */
                memcpy(addr.sa_data, new_slave->perm_hwaddr, ETH_ALEN);
                addr.sa_family = slave_dev->type;
                dev_set_mac_address(slave_dev, &addr);
@@ -1693,20 +1794,18 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
                return -EINVAL;
        }
 
-       mac_addr_differ = memcmp(bond_dev->dev_addr,
-                                slave->perm_hwaddr,
-                                ETH_ALEN);
-       if (!mac_addr_differ && (bond->slave_cnt > 1)) {
-               printk(KERN_WARNING DRV_NAME
-                      ": %s: Warning: the permanent HWaddr of %s - "
-                      "%s - is still in use by %s. "
-                      "Set the HWaddr of %s to a different address "
-                      "to avoid conflicts.\n",
-                      bond_dev->name,
-                      slave_dev->name,
-                      print_mac(mac, slave->perm_hwaddr),
-                      bond_dev->name,
-                      slave_dev->name);
+       if (!bond->params.fail_over_mac) {
+               mac_addr_differ = memcmp(bond_dev->dev_addr, slave->perm_hwaddr,
+                                        ETH_ALEN);
+               if (!mac_addr_differ && (bond->slave_cnt > 1))
+                       printk(KERN_WARNING DRV_NAME
+                              ": %s: Warning: the permanent HWaddr of %s - "
+                              "%s - is still in use by %s. "
+                              "Set the HWaddr of %s to a different address "
+                              "to avoid conflicts.\n",
+                              bond_dev->name, slave_dev->name,
+                              print_mac(mac, slave->perm_hwaddr),
+                              bond_dev->name, slave_dev->name);
        }
 
        /* Inform AD package of unbinding of slave. */
@@ -1833,7 +1932,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
        /* close slave before restoring its mac address */
        dev_close(slave_dev);
 
-       if (!bond->params.fail_over_mac) {
+       if (bond->params.fail_over_mac != BOND_FOM_ACTIVE) {
                /* restore original ("permanent") mac address */
                memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
                addr.sa_family = slave_dev->type;
@@ -2144,7 +2243,7 @@ static int __bond_mii_monitor(struct bonding *bond, int have_locks)
                        dprintk("sending delayed gratuitous arp on on %s\n",
                                bond->curr_active_slave->dev->name);
                        bond_send_gratuitous_arp(bond);
-                       bond->send_grat_arp = 0;
+                       bond->send_grat_arp--;
                }
        }
        read_lock(&bond->curr_slave_lock);
@@ -2426,37 +2525,14 @@ out:
        return addr;
 }
 
-static int bond_has_ip(struct bonding *bond)
-{
-       struct vlan_entry *vlan, *vlan_next;
-
-       if (bond->master_ip)
-               return 1;
-
-       if (list_empty(&bond->vlan_list))
-               return 0;
-
-       list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
-                                vlan_list) {
-               if (vlan->vlan_ip)
-                       return 1;
-       }
-
-       return 0;
-}
-
 static int bond_has_this_ip(struct bonding *bond, __be32 ip)
 {
-       struct vlan_entry *vlan, *vlan_next;
+       struct vlan_entry *vlan;
 
        if (ip == bond->master_ip)
                return 1;
 
-       if (list_empty(&bond->vlan_list))
-               return 0;
-
-       list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
-                                vlan_list) {
+       list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
                if (ip == vlan->vlan_ip)
                        return 1;
        }
@@ -2498,7 +2574,7 @@ static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
 {
        int i, vlan_id, rv;
        __be32 *targets = bond->params.arp_targets;
-       struct vlan_entry *vlan, *vlan_next;
+       struct vlan_entry *vlan;
        struct net_device *vlan_dev;
        struct flowi fl;
        struct rtable *rt;
@@ -2545,8 +2621,7 @@ static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
                }
 
                vlan_id = 0;
-               list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
-                                        vlan_list) {
+               list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
                        vlan_dev = vlan_group_get_device(bond->vlgrp, vlan->vlan_id);
                        if (vlan_dev == rt->u.dst.dev) {
                                vlan_id = vlan->vlan_id;
@@ -2764,8 +2839,7 @@ void bond_loadbalance_arp_mon(struct work_struct *work)
                         * if we don't know our ip yet
                         */
                        if (time_after_eq(jiffies, slave->dev->trans_start + 2*delta_in_ticks) ||
-                           (time_after_eq(jiffies, slave->dev->last_rx + 2*delta_in_ticks) &&
-                            bond_has_ip(bond))) {
+                           (time_after_eq(jiffies, slave->dev->last_rx + 2*delta_in_ticks))) {
 
                                slave->link  = BOND_LINK_DOWN;
                                slave->state = BOND_STATE_BACKUP;
@@ -2813,246 +2887,299 @@ out:
 }
 
 /*
- * When using arp monitoring in active-backup mode, this function is
- * called to determine if any backup slaves have went down or a new
- * current slave needs to be found.
- * The backup slaves never generate traffic, they are considered up by merely
- * receiving traffic. If the current slave goes down, each backup slave will
- * be given the opportunity to tx/rx an arp before being taken down - this
- * prevents all slaves from being taken down due to the current slave not
- * sending any traffic for the backups to receive. The arps are not necessarily
- * necessary, any tx and rx traffic will keep the current slave up. While any
- * rx traffic will keep the backup slaves up, the current slave is responsible
- * for generating traffic to keep them up regardless of any other traffic they
- * may have received.
- * see loadbalance_arp_monitor for arp monitoring in load balancing mode
+ * Called to inspect slaves for active-backup mode ARP monitor link state
+ * changes.  Sets new_link in slaves to specify what action should take
+ * place for the slave.  Returns 0 if no changes are found, >0 if changes
+ * to link states must be committed.
+ *
+ * Called with bond->lock held for read.
  */
-void bond_activebackup_arp_mon(struct work_struct *work)
+static int bond_ab_arp_inspect(struct bonding *bond, int delta_in_ticks)
 {
-       struct bonding *bond = container_of(work, struct bonding,
-                                           arp_work.work);
        struct slave *slave;
-       int delta_in_ticks;
-       int i;
+       int i, commit = 0;
 
-       read_lock(&bond->lock);
+       bond_for_each_slave(bond, slave, i) {
+               slave->new_link = BOND_LINK_NOCHANGE;
 
-       delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
+               if (slave->link != BOND_LINK_UP) {
+                       if (time_before_eq(jiffies, slave_last_rx(bond, slave) +
+                                          delta_in_ticks)) {
+                               slave->new_link = BOND_LINK_UP;
+                               commit++;
+                       }
 
-       if (bond->kill_timers) {
-               goto out;
-       }
+                       continue;
+               }
 
-       if (bond->slave_cnt == 0) {
-               goto re_arm;
+               /*
+                * Give slaves 2*delta after being enslaved or made
+                * active.  This avoids bouncing, as the last receive
+                * times need a full ARP monitor cycle to be updated.
+                */
+               if (!time_after_eq(jiffies, slave->jiffies +
+                                  2 * delta_in_ticks))
+                       continue;
+
+               /*
+                * Backup slave is down if:
+                * - No current_arp_slave AND
+                * - more than 3*delta since last receive AND
+                * - the bond has an IP address
+                *
+                * Note: a non-null current_arp_slave indicates
+                * the curr_active_slave went down and we are
+                * searching for a new one; under this condition
+                * we only take the curr_active_slave down - this
+                * gives each slave a chance to tx/rx traffic
+                * before being taken out
+                */
+               if (slave->state == BOND_STATE_BACKUP &&
+                   !bond->current_arp_slave &&
+                   time_after(jiffies, slave_last_rx(bond, slave) +
+                              3 * delta_in_ticks)) {
+                       slave->new_link = BOND_LINK_DOWN;
+                       commit++;
+               }
+
+               /*
+                * Active slave is down if:
+                * - more than 2*delta since transmitting OR
+                * - (more than 2*delta since receive AND
+                *    the bond has an IP address)
+                */
+               if ((slave->state == BOND_STATE_ACTIVE) &&
+                   (time_after_eq(jiffies, slave->dev->trans_start +
+                                   2 * delta_in_ticks) ||
+                     (time_after_eq(jiffies, slave_last_rx(bond, slave)
+                                    + 2 * delta_in_ticks)))) {
+                       slave->new_link = BOND_LINK_DOWN;
+                       commit++;
+               }
        }
 
-       /* determine if any slave has come up or any backup slave has
-        * gone down
-        * TODO: what about up/down delay in arp mode? it wasn't here before
-        *       so it can wait
+       read_lock(&bond->curr_slave_lock);
+
+       /*
+        * Trigger a commit if the primary option setting has changed.
         */
-       bond_for_each_slave(bond, slave, i) {
-               if (slave->link != BOND_LINK_UP) {
-                       if (time_before_eq(jiffies,
-                           slave_last_rx(bond, slave) + delta_in_ticks)) {
+       if (bond->primary_slave &&
+           (bond->primary_slave != bond->curr_active_slave) &&
+           (bond->primary_slave->link == BOND_LINK_UP))
+               commit++;
 
-                               slave->link = BOND_LINK_UP;
+       read_unlock(&bond->curr_slave_lock);
 
-                               write_lock_bh(&bond->curr_slave_lock);
+       return commit;
+}
 
-                               if ((!bond->curr_active_slave) &&
-                                   time_before_eq(jiffies, slave->dev->trans_start + delta_in_ticks)) {
-                                       bond_change_active_slave(bond, slave);
-                                       bond->current_arp_slave = NULL;
-                               } else if (bond->curr_active_slave != slave) {
-                                       /* this slave has just come up but we
-                                        * already have a current slave; this
-                                        * can also happen if bond_enslave adds
-                                        * a new slave that is up while we are
-                                        * searching for a new slave
-                                        */
-                                       bond_set_slave_inactive_flags(slave);
-                                       bond->current_arp_slave = NULL;
-                               }
+/*
+ * Called to commit link state changes noted by inspection step of
+ * active-backup mode ARP monitor.
+ *
+ * Called with RTNL and bond->lock for read.
+ */
+static void bond_ab_arp_commit(struct bonding *bond, int delta_in_ticks)
+{
+       struct slave *slave;
+       int i;
 
-                               bond_set_carrier(bond);
+       bond_for_each_slave(bond, slave, i) {
+               switch (slave->new_link) {
+               case BOND_LINK_NOCHANGE:
+                       continue;
 
-                               if (slave == bond->curr_active_slave) {
-                                       printk(KERN_INFO DRV_NAME
-                                              ": %s: %s is up and now the "
-                                              "active interface\n",
-                                              bond->dev->name,
-                                              slave->dev->name);
-                                       netif_carrier_on(bond->dev);
-                               } else {
-                                       printk(KERN_INFO DRV_NAME
-                                              ": %s: backup interface %s is "
-                                              "now up\n",
-                                              bond->dev->name,
-                                              slave->dev->name);
-                               }
+               case BOND_LINK_UP:
+                       write_lock_bh(&bond->curr_slave_lock);
 
-                               write_unlock_bh(&bond->curr_slave_lock);
-                       }
-               } else {
-                       read_lock(&bond->curr_slave_lock);
+                       if (!bond->curr_active_slave &&
+                           time_before_eq(jiffies, slave->dev->trans_start +
+                                          delta_in_ticks)) {
+                               slave->link = BOND_LINK_UP;
+                               bond_change_active_slave(bond, slave);
+                               bond->current_arp_slave = NULL;
 
-                       if ((slave != bond->curr_active_slave) &&
-                           (!bond->current_arp_slave) &&
-                           (time_after_eq(jiffies, slave_last_rx(bond, slave) + 3*delta_in_ticks) &&
-                            bond_has_ip(bond))) {
-                               /* a backup slave has gone down; three times
-                                * the delta allows the current slave to be
-                                * taken out before the backup slave.
-                                * note: a non-null current_arp_slave indicates
-                                * the curr_active_slave went down and we are
-                                * searching for a new one; under this
-                                * condition we only take the curr_active_slave
-                                * down - this gives each slave a chance to
-                                * tx/rx traffic before being taken out
+                               printk(KERN_INFO DRV_NAME
+                                      ": %s: %s is up and now the "
+                                      "active interface\n",
+                                      bond->dev->name, slave->dev->name);
+
+                       } else if (bond->curr_active_slave != slave) {
+                               /* this slave has just come up but we
+                                * already have a current slave; this can
+                                * also happen if bond_enslave adds a new
+                                * slave that is up while we are searching
+                                * for a new slave
                                 */
+                               slave->link = BOND_LINK_UP;
+                               bond_set_slave_inactive_flags(slave);
+                               bond->current_arp_slave = NULL;
 
-                               read_unlock(&bond->curr_slave_lock);
+                               printk(KERN_INFO DRV_NAME
+                                      ": %s: backup interface %s is now up\n",
+                                      bond->dev->name, slave->dev->name);
+                       }
 
-                               slave->link  = BOND_LINK_DOWN;
+                       write_unlock_bh(&bond->curr_slave_lock);
 
-                               if (slave->link_failure_count < UINT_MAX) {
-                                       slave->link_failure_count++;
-                               }
+                       break;
+
+               case BOND_LINK_DOWN:
+                       if (slave->link_failure_count < UINT_MAX)
+                               slave->link_failure_count++;
+
+                       slave->link = BOND_LINK_DOWN;
+
+                       if (slave == bond->curr_active_slave) {
+                               printk(KERN_INFO DRV_NAME
+                                      ": %s: link status down for active "
+                                      "interface %s, disabling it\n",
+                                      bond->dev->name, slave->dev->name);
 
                                bond_set_slave_inactive_flags(slave);
 
+                               write_lock_bh(&bond->curr_slave_lock);
+
+                               bond_select_active_slave(bond);
+                               if (bond->curr_active_slave)
+                                       bond->curr_active_slave->jiffies =
+                                               jiffies;
+
+                               write_unlock_bh(&bond->curr_slave_lock);
+
+                               bond->current_arp_slave = NULL;
+
+                       } else if (slave->state == BOND_STATE_BACKUP) {
                                printk(KERN_INFO DRV_NAME
                                       ": %s: backup interface %s is now down\n",
-                                      bond->dev->name,
-                                      slave->dev->name);
-                       } else {
-                               read_unlock(&bond->curr_slave_lock);
+                                      bond->dev->name, slave->dev->name);
+
+                               bond_set_slave_inactive_flags(slave);
                        }
+                       break;
+
+               default:
+                       printk(KERN_ERR DRV_NAME
+                              ": %s: impossible: new_link %d on slave %s\n",
+                              bond->dev->name, slave->new_link,
+                              slave->dev->name);
                }
        }
 
-       read_lock(&bond->curr_slave_lock);
-       slave = bond->curr_active_slave;
-       read_unlock(&bond->curr_slave_lock);
-
-       if (slave) {
-               /* if we have sent traffic in the past 2*arp_intervals but
-                * haven't xmit and rx traffic in that time interval, select
-                * a different slave. slave->jiffies is only updated when
-                * a slave first becomes the curr_active_slave - not necessarily
-                * after every arp; this ensures the slave has a full 2*delta
-                * before being taken out. if a primary is being used, check
-                * if it is up and needs to take over as the curr_active_slave
-                */
-               if ((time_after_eq(jiffies, slave->dev->trans_start + 2*delta_in_ticks) ||
-                       (time_after_eq(jiffies, slave_last_rx(bond, slave) + 2*delta_in_ticks) &&
-                        bond_has_ip(bond))) &&
-                       time_after_eq(jiffies, slave->jiffies + 2*delta_in_ticks)) {
+       /*
+        * No race with changes to primary via sysfs, as we hold rtnl.
+        */
+       if (bond->primary_slave &&
+           (bond->primary_slave != bond->curr_active_slave) &&
+           (bond->primary_slave->link == BOND_LINK_UP)) {
+               write_lock_bh(&bond->curr_slave_lock);
+               bond_change_active_slave(bond, bond->primary_slave);
+               write_unlock_bh(&bond->curr_slave_lock);
+       }
 
-                       slave->link  = BOND_LINK_DOWN;
+       bond_set_carrier(bond);
+}
 
-                       if (slave->link_failure_count < UINT_MAX) {
-                               slave->link_failure_count++;
-                       }
+/*
+ * Send ARP probes for active-backup mode ARP monitor.
+ *
+ * Called with bond->lock held for read.
+ */
+static void bond_ab_arp_probe(struct bonding *bond)
+{
+       struct slave *slave;
+       int i;
 
-                       printk(KERN_INFO DRV_NAME
-                              ": %s: link status down for active interface "
-                              "%s, disabling it\n",
-                              bond->dev->name,
-                              slave->dev->name);
+       read_lock(&bond->curr_slave_lock);
 
-                       write_lock_bh(&bond->curr_slave_lock);
+       if (bond->current_arp_slave && bond->curr_active_slave)
+               printk("PROBE: c_arp %s && cas %s BAD\n",
+                      bond->current_arp_slave->dev->name,
+                      bond->curr_active_slave->dev->name);
 
-                       bond_select_active_slave(bond);
-                       slave = bond->curr_active_slave;
+       if (bond->curr_active_slave) {
+               bond_arp_send_all(bond, bond->curr_active_slave);
+               read_unlock(&bond->curr_slave_lock);
+               return;
+       }
 
-                       write_unlock_bh(&bond->curr_slave_lock);
+       read_unlock(&bond->curr_slave_lock);
 
-                       bond->current_arp_slave = slave;
+       /* 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 (slave) {
-                               slave->jiffies = jiffies;
-                       }
-               } else if ((bond->primary_slave) &&
-                          (bond->primary_slave != slave) &&
-                          (bond->primary_slave->link == BOND_LINK_UP)) {
-                       /* at this point, slave is the curr_active_slave */
-                       printk(KERN_INFO DRV_NAME
-                              ": %s: changing from interface %s to primary "
-                              "interface %s\n",
-                              bond->dev->name,
-                              slave->dev->name,
-                              bond->primary_slave->dev->name);
+       if (!bond->current_arp_slave) {
+               bond->current_arp_slave = bond->first_slave;
+               if (!bond->current_arp_slave)
+                       return;
+       }
 
-                       /* primary is up so switch to it */
-                       write_lock_bh(&bond->curr_slave_lock);
-                       bond_change_active_slave(bond, bond->primary_slave);
-                       write_unlock_bh(&bond->curr_slave_lock);
+       bond_set_slave_inactive_flags(bond->current_arp_slave);
 
-                       slave = bond->primary_slave;
+       /* search for next candidate */
+       bond_for_each_slave_from(bond, slave, i, bond->current_arp_slave->next) {
+               if (IS_UP(slave->dev)) {
+                       slave->link = BOND_LINK_BACK;
+                       bond_set_slave_active_flags(slave);
+                       bond_arp_send_all(bond, slave);
                        slave->jiffies = jiffies;
-               } else {
-                       bond->current_arp_slave = NULL;
+                       bond->current_arp_slave = slave;
+                       break;
                }
 
-               /* the current slave must tx an arp to ensure backup slaves
-                * rx traffic
+               /* if the link state is up at this point, we
+                * mark it down - this can happen if we have
+                * simultaneous link failures and
+                * reselect_active_interface doesn't make this
+                * one the current slave so it is still marked
+                * up when it is actually down
                 */
-               if (slave && bond_has_ip(bond)) {
-                       bond_arp_send_all(bond, slave);
+               if (slave->link == BOND_LINK_UP) {
+                       slave->link = BOND_LINK_DOWN;
+                       if (slave->link_failure_count < UINT_MAX)
+                               slave->link_failure_count++;
+
+                       bond_set_slave_inactive_flags(slave);
+
+                       printk(KERN_INFO DRV_NAME
+                              ": %s: backup interface %s is now down.\n",
+                              bond->dev->name, slave->dev->name);
                }
        }
+}
 
-       /* 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 (!slave) {
-               if (!bond->current_arp_slave) {
-                       bond->current_arp_slave = bond->first_slave;
-               }
+void bond_activebackup_arp_mon(struct work_struct *work)
+{
+       struct bonding *bond = container_of(work, struct bonding,
+                                           arp_work.work);
+       int delta_in_ticks;
 
-               if (bond->current_arp_slave) {
-                       bond_set_slave_inactive_flags(bond->current_arp_slave);
+       read_lock(&bond->lock);
 
-                       /* search for next candidate */
-                       bond_for_each_slave_from(bond, slave, i, bond->current_arp_slave->next) {
-                               if (IS_UP(slave->dev)) {
-                                       slave->link = BOND_LINK_BACK;
-                                       bond_set_slave_active_flags(slave);
-                                       bond_arp_send_all(bond, slave);
-                                       slave->jiffies = jiffies;
-                                       bond->current_arp_slave = slave;
-                                       break;
-                               }
+       if (bond->kill_timers)
+               goto out;
 
-                               /* if the link state is up at this point, we
-                                * mark it down - this can happen if we have
-                                * simultaneous link failures and
-                                * reselect_active_interface doesn't make this
-                                * one the current slave so it is still marked
-                                * up when it is actually down
-                                */
-                               if (slave->link == BOND_LINK_UP) {
-                                       slave->link  = BOND_LINK_DOWN;
-                                       if (slave->link_failure_count < UINT_MAX) {
-                                               slave->link_failure_count++;
-                                       }
+       delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
+
+       if (bond->slave_cnt == 0)
+               goto re_arm;
 
-                                       bond_set_slave_inactive_flags(slave);
+       if (bond_ab_arp_inspect(bond, delta_in_ticks)) {
+               read_unlock(&bond->lock);
+               rtnl_lock();
+               read_lock(&bond->lock);
 
-                                       printk(KERN_INFO DRV_NAME
-                                              ": %s: backup interface %s is "
-                                              "now down.\n",
-                                              bond->dev->name,
-                                              slave->dev->name);
-                               }
-                       }
-               }
+               bond_ab_arp_commit(bond, delta_in_ticks);
+
+               read_unlock(&bond->lock);
+               rtnl_unlock();
+               read_lock(&bond->lock);
        }
 
+       bond_ab_arp_probe(bond);
+
 re_arm:
        if (bond->params.arp_interval) {
                queue_delayed_work(bond->wq, &bond->arp_work, delta_in_ticks);
@@ -3128,7 +3255,8 @@ static void bond_info_show_master(struct seq_file *seq)
 
        if (bond->params.mode == BOND_MODE_ACTIVEBACKUP &&
            bond->params.fail_over_mac)
-               seq_printf(seq, " (fail_over_mac)");
+               seq_printf(seq, " (fail_over_mac %s)",
+                  fail_over_mac_tbl[bond->params.fail_over_mac].modename);
 
        seq_printf(seq, "\n");
 
@@ -3500,13 +3628,13 @@ static int bond_inetaddr_event(struct notifier_block *this, unsigned long event,
 {
        struct in_ifaddr *ifa = ptr;
        struct net_device *vlan_dev, *event_dev = ifa->ifa_dev->dev;
-       struct bonding *bond, *bond_next;
-       struct vlan_entry *vlan, *vlan_next;
+       struct bonding *bond;
+       struct vlan_entry *vlan;
 
        if (dev_net(ifa->ifa_dev->dev) != &init_net)
                return NOTIFY_DONE;
 
-       list_for_each_entry_safe(bond, bond_next, &bond_dev_list, bond_list) {
+       list_for_each_entry(bond, &bond_dev_list, bond_list) {
                if (bond->dev == event_dev) {
                        switch (event) {
                        case NETDEV_UP:
@@ -3520,11 +3648,7 @@ static int bond_inetaddr_event(struct notifier_block *this, unsigned long event,
                        }
                }
 
-               if (list_empty(&bond->vlan_list))
-                       continue;
-
-               list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
-                                        vlan_list) {
+               list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
                        vlan_dev = vlan_group_get_device(bond->vlgrp, vlan->vlan_id);
                        if (vlan_dev == event_dev) {
                                switch (event) {
@@ -4060,10 +4184,10 @@ static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
        dprintk("bond=%p, name=%s\n", bond, (bond_dev ? bond_dev->name : "None"));
 
        /*
-        * If fail_over_mac is enabled, do nothing and return success.
-        * Returning an error causes ifenslave to fail.
+        * If fail_over_mac is set to active, do nothing and return
+        * success.  Returning an error causes ifenslave to fail.
         */
-       if (bond->params.fail_over_mac)
+       if (bond->params.fail_over_mac == BOND_FOM_ACTIVE)
                return 0;
 
        if (!is_valid_ether_addr(sa->sa_data)) {
@@ -4568,7 +4692,7 @@ int bond_parse_parm(const char *buf, struct bond_parm_tbl *tbl)
 
 static int bond_check_params(struct bond_params *params)
 {
-       int arp_validate_value;
+       int arp_validate_value, fail_over_mac_value;
 
        /*
         * Convert string parameters.
@@ -4658,6 +4782,13 @@ static int bond_check_params(struct bond_params *params)
                use_carrier = 1;
        }
 
+       if (num_grat_arp < 0 || num_grat_arp > 255) {
+               printk(KERN_WARNING DRV_NAME
+                      ": Warning: num_grat_arp (%d) not in range 0-255 so it "
+                      "was reset to 1 \n", num_grat_arp);
+               num_grat_arp = 1;
+       }
+
        /* reset values for 802.3ad */
        if (bond_mode == BOND_MODE_8023AD) {
                if (!miimon) {
@@ -4836,15 +4967,29 @@ static int bond_check_params(struct bond_params *params)
                primary = NULL;
        }
 
-       if (fail_over_mac && (bond_mode != BOND_MODE_ACTIVEBACKUP))
-               printk(KERN_WARNING DRV_NAME
-                      ": Warning: fail_over_mac only affects "
-                      "active-backup mode.\n");
+       if (fail_over_mac) {
+               fail_over_mac_value = bond_parse_parm(fail_over_mac,
+                                                     fail_over_mac_tbl);
+               if (fail_over_mac_value == -1) {
+                       printk(KERN_ERR DRV_NAME
+                              ": Error: invalid fail_over_mac \"%s\"\n",
+                              arp_validate == NULL ? "NULL" : arp_validate);
+                       return -EINVAL;
+               }
+
+               if (bond_mode != BOND_MODE_ACTIVEBACKUP)
+                       printk(KERN_WARNING DRV_NAME
+                              ": Warning: fail_over_mac only affects "
+                              "active-backup mode.\n");
+       } else {
+               fail_over_mac_value = BOND_FOM_NONE;
+       }
 
        /* fill params struct with the proper values */
        params->mode = bond_mode;
        params->xmit_policy = xmit_hashtype;
        params->miimon = miimon;
+       params->num_grat_arp = num_grat_arp;
        params->arp_interval = arp_interval;
        params->arp_validate = arp_validate_value;
        params->updelay = updelay;
@@ -4852,7 +4997,7 @@ static int bond_check_params(struct bond_params *params)
        params->use_carrier = use_carrier;
        params->lacp_fast = lacp_fast;
        params->primary[0] = 0;
-       params->fail_over_mac = fail_over_mac;
+       params->fail_over_mac = fail_over_mac_value;
 
        if (primary) {
                strncpy(params->primary, primary, IFNAMSIZ);
@@ -4871,10 +5016,10 @@ static struct lock_class_key bonding_netdev_xmit_lock_key;
  * Caller must NOT hold rtnl_lock; we need to release it here before we
  * set up our sysfs entries.
  */
-int bond_create(char *name, struct bond_params *params, struct bonding **newbond)
+int bond_create(char *name, struct bond_params *params)
 {
        struct net_device *bond_dev;
-       struct bonding *bond, *nxt;
+       struct bonding *bond;
        int res;
 
        rtnl_lock();
@@ -4882,7 +5027,7 @@ int bond_create(char *name, struct bond_params *params, struct bonding **newbond
 
        /* Check to see if the bond already exists. */
        if (name) {
-               list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
+               list_for_each_entry(bond, &bond_dev_list, bond_list)
                        if (strnicmp(bond->dev->name, name, IFNAMSIZ) == 0) {
                                printk(KERN_ERR DRV_NAME
                               ": cannot add bond %s; it already exists\n",
@@ -4925,9 +5070,6 @@ int bond_create(char *name, struct bond_params *params, struct bonding **newbond
 
        lockdep_set_class(&bond_dev->_xmit_lock, &bonding_netdev_xmit_lock_key);
 
-       if (newbond)
-               *newbond = bond_dev->priv;
-
        netif_carrier_off(bond_dev);
 
        up_write(&bonding_rwsem);
@@ -4957,7 +5099,7 @@ static int __init bonding_init(void)
 {
        int i;
        int res;
-       struct bonding *bond, *nxt;
+       struct bonding *bond;
 
        printk(KERN_INFO "%s", version);
 
@@ -4973,7 +5115,7 @@ static int __init bonding_init(void)
        init_rwsem(&bonding_rwsem);
 
        for (i = 0; i < max_bonds; i++) {
-               res = bond_create(NULL, &bonding_defaults, NULL);
+               res = bond_create(NULL, &bonding_defaults);
                if (res)
                        goto err;
        }
@@ -4987,7 +5129,7 @@ static int __init bonding_init(void)
 
        goto out;
 err:
-       list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list) {
+       list_for_each_entry(bond, &bond_dev_list, bond_list) {
                bond_work_cancel_all(bond);
                destroy_workqueue(bond->wq);
        }