net: make dev->master general

dev->master is now tightly connected to bonding driver. This patch makes
this pointer more general and ready to be used by others.

 - netdev_set_master() - bond specifics moved to new function
   netdev_set_bond_master()
 - introduced netif_is_bond_slave() to check if device is a bonding slave

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 54 insertions, 20 deletions

diff --git a/drivers/infiniband/hw/nes/nes.c b/drivers/infiniband/hw/nes/nes.c
index 3b4ec3238ceb..3d7f3664b67b 100644
--- a/drivers/infiniband/hw/nes/nes.c
+++ b/drivers/infiniband/hw/nes/nes.c
@@ -153,7 +153,8 @@ static int nes_inetaddr_event(struct notifier_block *notifier,
                                 nesdev, nesdev->netdev[0]->name);
                 netdev = nesdev->netdev[0];
                 nesvnic = netdev_priv(netdev);
-                is_bonded = (netdev->master == event_netdev);
+                is_bonded = netif_is_bond_slave(netdev) &&
+                            (netdev->master == event_netdev);
                 if ((netdev == event_netdev) || is_bonded) {
                         if (nesvnic->rdma_enabled == 0) {
                                 nes_debug(NES_DBG_NETDEV, "Returning without processing event for %s since"
diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index 009ec814d517..ec3aa11c36cb 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -1118,7 +1118,7 @@ static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip, int arpi
                 return rc;
         }
 
-        if (nesvnic->netdev->master)
+        if (netif_is_bond_slave(netdev))
                 netdev = nesvnic->netdev->master;
         else
                 netdev = nesvnic->netdev;
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 1df9f0ea9184..9f877878d636 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1594,9 +1594,9 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
                 }
         }
 
-        res = netdev_set_master(slave_dev, bond_dev);
+        res = netdev_set_bond_master(slave_dev, bond_dev);
         if (res) {
-                pr_debug("Error %d calling netdev_set_master\n", res);
+                pr_debug("Error %d calling netdev_set_bond_master\n", res);
                 goto err_restore_mac;
         }
         /* open the slave since the application closed it */
@@ -1812,7 +1812,7 @@ err_close:
         dev_close(slave_dev);
 
 err_unset_master:
-        netdev_set_master(slave_dev, NULL);
+        netdev_set_bond_master(slave_dev, NULL);
 
 err_restore_mac:
         if (!bond->params.fail_over_mac) {
@@ -1992,7 +1992,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
                 netif_addr_unlock_bh(bond_dev);
         }
 
-        netdev_set_master(slave_dev, NULL);
+        netdev_set_bond_master(slave_dev, NULL);
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
         read_lock_bh(&bond->lock);
@@ -2114,7 +2114,7 @@ static int bond_release_all(struct net_device *bond_dev)
                         netif_addr_unlock_bh(bond_dev);
                 }
 
-                netdev_set_master(slave_dev, NULL);
+                netdev_set_bond_master(slave_dev, NULL);
 
                 /* close slave before restoring its mac address */
                 dev_close(slave_dev);
diff --git a/drivers/net/cxgb3/cxgb3_offload.c b/drivers/net/cxgb3/cxgb3_offload.c
index 7ea94b5205f8..862804f32b6e 100644
--- a/drivers/net/cxgb3/cxgb3_offload.c
+++ b/drivers/net/cxgb3/cxgb3_offload.c
@@ -186,9 +186,10 @@ static struct net_device *get_iff_from_mac(struct adapter *adapter,
                                 dev = NULL;
                                 if (grp)
                                         dev = vlan_group_get_device(grp, vlan);
-                        } else
+                        } else if (netif_is_bond_slave(dev)) {
                                 while (dev->master)
                                         dev = dev->master;
+                        }
                         return dev;
                 }
         }
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 5a5baeaaa50f..5a42b1003767 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2377,6 +2377,8 @@ extern int		netdev_max_backlog;
 extern int              netdev_tstamp_prequeue;
 extern int              weight_p;
 extern int              netdev_set_master(struct net_device *dev, struct net_device *master);
+extern int netdev_set_bond_master(struct net_device *dev,
+                                  struct net_device *master);
 extern int skb_checksum_help(struct sk_buff *skb);
 extern struct sk_buff *skb_gso_segment(struct sk_buff *skb, u32 features);
 #ifdef CONFIG_BUG
@@ -2437,6 +2439,11 @@ static inline void netif_set_gso_max_size(struct net_device *dev,
         dev->gso_max_size = size;
 }
 
+static inline int netif_is_bond_slave(struct net_device *dev)
+{
+        return dev->flags & IFF_SLAVE && dev->priv_flags & IFF_BONDING;
+}
+
 extern struct pernet_operations __net_initdata loopback_net_ops;
 
 static inline int dev_ethtool_get_settings(struct net_device *dev,
diff --git a/net/core/dev.c b/net/core/dev.c
index d874fd1baf49..a4132766d363 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3146,7 +3146,6 @@ static int __netif_receive_skb(struct sk_buff *skb)
         struct packet_type *ptype, *pt_prev;
         rx_handler_func_t *rx_handler;
         struct net_device *orig_dev;
-        struct net_device *master;
         struct net_device *null_or_orig;
         struct net_device *orig_or_bond;
         int ret = NET_RX_DROP;
@@ -3173,15 +3172,19 @@ static int __netif_receive_skb(struct sk_buff *skb)
          */
         null_or_orig = NULL;
         orig_dev = skb->dev;
-        master = ACCESS_ONCE(orig_dev->master);
         if (skb->deliver_no_wcard)
                 null_or_orig = orig_dev;
-        else if (master) {
-                if (__skb_bond_should_drop(skb, master)) {
-                        skb->deliver_no_wcard = 1;
-                        null_or_orig = orig_dev; /* deliver only exact match */
-                } else
-                        skb->dev = master;
+        else if (netif_is_bond_slave(orig_dev)) {
+                struct net_device *bond_master = ACCESS_ONCE(orig_dev->master);
+
+                if (likely(bond_master)) {
+                        if (__skb_bond_should_drop(skb, bond_master)) {
+                                skb->deliver_no_wcard = 1;
+                                /* deliver only exact match */
+                                null_or_orig = orig_dev;
+                        } else
+                                skb->dev = bond_master;
+                }
         }
 
         __this_cpu_inc(softnet_data.processed);
@@ -4346,15 +4349,14 @@ static int __init dev_proc_init(void)
 
 
 /**
- *      netdev_set_master       -       set up master/slave pair
+ *      netdev_set_master       -       set up master pointer
  *      @slave: slave device
  *      @master: new master device
  *
  *      Changes the master device of the slave. Pass %NULL to break the
  *      bonding. The caller must hold the RTNL semaphore. On a failure
  *      a negative errno code is returned. On success the reference counts
- *      are adjusted, %RTM_NEWLINK is sent to the routing socket and the
- *      function returns zero.
+ *      are adjusted and the function returns zero.
  */
 int netdev_set_master(struct net_device *slave, struct net_device *master)
 {
@@ -4374,6 +4376,29 @@ int netdev_set_master(struct net_device *slave, struct net_device *master)
                 synchronize_net();
                 dev_put(old);
         }
+        return 0;
+}
+EXPORT_SYMBOL(netdev_set_master);
+
+/**
+ *      netdev_set_bond_master  -       set up bonding master/slave pair
+ *      @slave: slave device
+ *      @master: new master device
+ *
+ *      Changes the master device of the slave. Pass %NULL to break the
+ *      bonding. The caller must hold the RTNL semaphore. On a failure
+ *      a negative errno code is returned. On success %RTM_NEWLINK is sent
+ *      to the routing socket and the function returns zero.
+ */
+int netdev_set_bond_master(struct net_device *slave, struct net_device *master)
+{
+        int err;
+
+        ASSERT_RTNL();
+
+        err = netdev_set_master(slave, master);
+        if (err)
+                return err;
         if (master)
                 slave->flags |= IFF_SLAVE;
         else
@@ -4382,7 +4407,7 @@ int netdev_set_master(struct net_device *slave, struct net_device *master)
         rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
         return 0;
 }
-EXPORT_SYMBOL(netdev_set_master);
+EXPORT_SYMBOL(netdev_set_bond_master);
 
 static void dev_change_rx_flags(struct net_device *dev, int flags)
 {