bonding: add bond_has_slaves() and use it

Currently we verify if we have slaves by checking if bond->slave_list is
empty. Create a define bond_has_slaves() and use it, a bit more readable
and easier to change in the future.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 25 insertions, 23 deletions

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index c861ee7e65ff..1337eafe4311 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -2117,7 +2117,7 @@ void bond_3ad_state_machine_handler(struct work_struct *work)
         read_lock(&bond->lock);
 
         //check if there are any slaves
-        if (list_empty(&bond->slave_list))
+        if (!bond_has_slaves(bond))
                 goto re_arm;
 
         // check if agg_select_timer timer after initialize is timed out
diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
index c5b85ad5554d..e96041816b5b 100644
--- a/drivers/net/bonding/bond_alb.c
+++ b/drivers/net/bonding/bond_alb.c
@@ -1178,7 +1178,7 @@ static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slav
         struct slave *tmp_slave1, *free_mac_slave = NULL;
         struct list_head *iter;
 
-        if (list_empty(&bond->slave_list)) {
+        if (!bond_has_slaves(bond)) {
                 /* this is the first slave */
                 return 0;
         }
@@ -1469,7 +1469,7 @@ void bond_alb_monitor(struct work_struct *work)
 
         read_lock(&bond->lock);
 
-        if (list_empty(&bond->slave_list)) {
+        if (!bond_has_slaves(bond)) {
                 bond_info->tx_rebalance_counter = 0;
                 bond_info->lp_counter = 0;
                 goto re_arm;
@@ -1606,7 +1606,7 @@ int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
  */
 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
 {
-        if (!list_empty(&bond->slave_list))
+        if (bond_has_slaves(bond))
                 alb_change_hw_addr_on_detach(bond, slave);
 
         tlb_clear_slave(bond, slave, 0);
@@ -1676,7 +1676,7 @@ void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave
         swap_slave = bond->curr_active_slave;
         rcu_assign_pointer(bond->curr_active_slave, new_slave);
 
-        if (!new_slave || list_empty(&bond->slave_list))
+        if (!new_slave || !bond_has_slaves(bond))
                 return;
 
         /* set the new curr_active_slave to the bonds mac address
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 3c96b1b10ba4..06ffc8ace54c 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -391,7 +391,7 @@ static int bond_set_carrier(struct bonding *bond)
         struct list_head *iter;
         struct slave *slave;
 
-        if (list_empty(&bond->slave_list))
+        if (!bond_has_slaves(bond))
                 goto down;
 
         if (bond->params.mode == BOND_MODE_8023AD)
@@ -1085,7 +1085,7 @@ static netdev_features_t bond_fix_features(struct net_device *dev,
         netdev_features_t mask;
         struct slave *slave;
 
-        if (list_empty(&bond->slave_list)) {
+        if (!bond_has_slaves(bond)) {
                 /* Disable adding VLANs to empty bond. But why? --mq */
                 features |= NETIF_F_VLAN_CHALLENGED;
                 return features;
@@ -1120,7 +1120,7 @@ static void bond_compute_features(struct bonding *bond)
         unsigned int gso_max_size = GSO_MAX_SIZE;
         u16 gso_max_segs = GSO_MAX_SEGS;
 
-        if (list_empty(&bond->slave_list))
+        if (!bond_has_slaves(bond))
                 goto done;
 
         bond_for_each_slave(bond, slave, iter) {
@@ -1310,7 +1310,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
          * bond ether type mutual exclusion - don't allow slaves of dissimilar
          * ether type (eg ARPHRD_ETHER and ARPHRD_INFINIBAND) share the same bond
          */
-        if (list_empty(&bond->slave_list)) {
+        if (!bond_has_slaves(bond)) {
                 if (bond_dev->type != slave_dev->type) {
                         pr_debug("%s: change device type from %d to %d\n",
                                  bond_dev->name,
@@ -1349,7 +1349,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
         }
 
         if (slave_ops->ndo_set_mac_address == NULL) {
-                if (list_empty(&bond->slave_list)) {
+                if (!bond_has_slaves(bond)) {
                         pr_warning("%s: Warning: The first slave device specified does not support setting the MAC address. Setting fail_over_mac to active.",
                                    bond_dev->name);
                         bond->params.fail_over_mac = BOND_FOM_ACTIVE;
@@ -1365,7 +1365,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 
         /* If this is the first slave, then we need to set the master's hardware
          * address to be the same as the slave's. */
-        if (list_empty(&bond->slave_list) &&
+        if (!bond_has_slaves(bond) &&
             bond->dev->addr_assign_type == NET_ADDR_RANDOM)
                 bond_set_dev_addr(bond->dev, slave_dev);
 
@@ -1696,7 +1696,7 @@ err_free:
 err_undo_flags:
         bond_compute_features(bond);
         /* Enslave of first slave has failed and we need to fix master's mac */
-        if (list_empty(&bond->slave_list) &&
+        if (!bond_has_slaves(bond) &&
             ether_addr_equal(bond_dev->dev_addr, slave_dev->dev_addr))
                 eth_hw_addr_random(bond_dev);
 
@@ -1776,7 +1776,7 @@ static int __bond_release_one(struct net_device *bond_dev,
 
         if (!all && !bond->params.fail_over_mac) {
                 if (ether_addr_equal(bond_dev->dev_addr, slave->perm_hwaddr) &&
-                    !list_empty(&bond->slave_list))
+                    bond_has_slaves(bond))
                         pr_warn("%s: Warning: the permanent HWaddr of %s - %pM - 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,
                                    slave->perm_hwaddr,
@@ -1819,7 +1819,7 @@ static int __bond_release_one(struct net_device *bond_dev,
                 write_lock_bh(&bond->lock);
         }
 
-        if (list_empty(&bond->slave_list)) {
+        if (!bond_has_slaves(bond)) {
                 bond_set_carrier(bond);
                 eth_hw_addr_random(bond_dev);
 
@@ -1835,7 +1835,7 @@ static int __bond_release_one(struct net_device *bond_dev,
         unblock_netpoll_tx();
         synchronize_rcu();
 
-        if (list_empty(&bond->slave_list)) {
+        if (!bond_has_slaves(bond)) {
                 call_netdevice_notifiers(NETDEV_CHANGEADDR, bond->dev);
                 call_netdevice_notifiers(NETDEV_RELEASE, bond->dev);
         }
@@ -1904,7 +1904,7 @@ static int  bond_release_and_destroy(struct net_device *bond_dev,
         int ret;
 
         ret = bond_release(bond_dev, slave_dev);
-        if (ret == 0 && list_empty(&bond->slave_list)) {
+        if (ret == 0 && !bond_has_slaves(bond)) {
                 bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
                 pr_info("%s: destroying bond %s.\n",
                         bond_dev->name, bond_dev->name);
@@ -2219,7 +2219,7 @@ void bond_mii_monitor(struct work_struct *work)
 
         delay = msecs_to_jiffies(bond->params.miimon);
 
-        if (list_empty(&bond->slave_list))
+        if (!bond_has_slaves(bond))
                 goto re_arm;
 
         should_notify_peers = bond_should_notify_peers(bond);
@@ -2513,7 +2513,7 @@ void bond_loadbalance_arp_mon(struct work_struct *work)
 
         read_lock(&bond->lock);
 
-        if (list_empty(&bond->slave_list))
+        if (!bond_has_slaves(bond))
                 goto re_arm;
 
         oldcurrent = bond->curr_active_slave;
@@ -2845,7 +2845,7 @@ void bond_activebackup_arp_mon(struct work_struct *work)
 
         delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
 
-        if (list_empty(&bond->slave_list))
+        if (!bond_has_slaves(bond))
                 goto re_arm;
 
         should_notify_peers = bond_should_notify_peers(bond);
@@ -3169,7 +3169,7 @@ static int bond_open(struct net_device *bond_dev)
 
         /* reset slave->backup and slave->inactive */
         read_lock(&bond->lock);
-        if (!list_empty(&bond->slave_list)) {
+        if (bond_has_slaves(bond)) {
                 read_lock(&bond->curr_slave_lock);
                 bond_for_each_slave(bond, slave, iter) {
                         if ((bond->params.mode == BOND_MODE_ACTIVEBACKUP)
@@ -3892,7 +3892,7 @@ static netdev_tx_t bond_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 return NETDEV_TX_BUSY;
 
         rcu_read_lock();
-        if (!list_empty(&bond->slave_list))
+        if (bond_has_slaves(bond))
                 ret = __bond_start_xmit(skb, dev);
         else
                 kfree_skb(skb);
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index e747415b5cb0..04d95d6f6c63 100644
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -327,7 +327,7 @@ static ssize_t bonding_store_mode(struct device *d,
                 goto out;
         }
 
-        if (!list_empty(&bond->slave_list)) {
+        if (bond_has_slaves(bond)) {
                 pr_err("unable to update mode of %s because it has slaves.\n",
                         bond->dev->name);
                 ret = -EPERM;
@@ -523,7 +523,7 @@ static ssize_t bonding_store_fail_over_mac(struct device *d,
         if (!rtnl_trylock())
                 return restart_syscall();
 
-        if (!list_empty(&bond->slave_list)) {
+        if (bond_has_slaves(bond)) {
                 pr_err("%s: Can't alter fail_over_mac with slaves in bond.\n",
                        bond->dev->name);
                 ret = -EPERM;
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 7c8a4b128f65..bcef15ec3459 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -72,6 +72,8 @@
         res; })
 
 /* slave list primitives */
+#define bond_has_slaves(bond) !list_empty(&(bond)->slave_list)
+
 #define bond_to_slave(ptr) list_entry(ptr, struct slave, list)
 
 /* IMPORTANT: bond_first/last_slave can return NULL in case of an empty list */