bonding: sync netpoll code with bridge

V4: rebase to net-next-2.6
V3: remove an useless #ifdef.

This patch unifies the netpoll code in bonding with netpoll code in bridge,
thanks to Herbert that code is much cleaner now.

Signed-off-by: WANG Cong <amwang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 118 insertions, 57 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 77e3c6a7176a..2ed662464cac 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -59,7 +59,6 @@
 #include <linux/uaccess.h>
 #include <linux/errno.h>
 #include <linux/netdevice.h>
-#include <linux/netpoll.h>
 #include <linux/inetdevice.h>
 #include <linux/igmp.h>
 #include <linux/etherdevice.h>
@@ -424,15 +423,11 @@ int bond_dev_queue_xmit(struct bonding *bond, struct sk_buff *skb,
 {
         skb->dev = slave_dev;
         skb->priority = 1;
-#ifdef CONFIG_NET_POLL_CONTROLLER
-        if (unlikely(bond->dev->priv_flags & IFF_IN_NETPOLL)) {
-                struct netpoll *np = bond->dev->npinfo->netpoll;
-                slave_dev->npinfo = bond->dev->npinfo;
+        if (unlikely(netpoll_tx_running(slave_dev))) {
                 slave_dev->priv_flags |= IFF_IN_NETPOLL;
-                netpoll_send_skb_on_dev(np, skb, slave_dev);
+                bond_netpoll_send_skb(bond_get_slave_by_dev(bond, slave_dev), skb);
                 slave_dev->priv_flags &= ~IFF_IN_NETPOLL;
         } else
-#endif
                 dev_queue_xmit(skb);
 
         return 0;
@@ -1288,63 +1283,113 @@ static void bond_detach_slave(struct bonding *bond, struct slave *slave)
 }
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
-/*
- * You must hold read lock on bond->lock before calling this.
- */
-static bool slaves_support_netpoll(struct net_device *bond_dev)
+static inline int slave_enable_netpoll(struct slave *slave)
 {
-        struct bonding *bond = netdev_priv(bond_dev);
-        struct slave *slave;
-        int i = 0;
-        bool ret = true;
+        struct netpoll *np;
+        int err = 0;
 
-        bond_for_each_slave(bond, slave, i) {
-                if ((slave->dev->priv_flags & IFF_DISABLE_NETPOLL) ||
-                    !slave->dev->netdev_ops->ndo_poll_controller)
-                        ret = false;
+        np = kzalloc(sizeof(*np), GFP_KERNEL);
+        err = -ENOMEM;
+        if (!np)
+                goto out;
+
+        np->dev = slave->dev;
+        err = __netpoll_setup(np);
+        if (err) {
+                kfree(np);
+                goto out;
         }
-        return i != 0 && ret;
+        slave->np = np;
+out:
+        return err;
+}
+static inline void slave_disable_netpoll(struct slave *slave)
+{
+        struct netpoll *np = slave->np;
+
+        if (!np)
+                return;
+
+        slave->np = NULL;
+        synchronize_rcu_bh();
+        __netpoll_cleanup(np);
+        kfree(np);
+}
+static inline bool slave_dev_support_netpoll(struct net_device *slave_dev)
+{
+        if (slave_dev->priv_flags & IFF_DISABLE_NETPOLL)
+                return false;
+        if (!slave_dev->netdev_ops->ndo_poll_controller)
+                return false;
+        return true;
 }
 
 static void bond_poll_controller(struct net_device *bond_dev)
 {
-        struct bonding *bond = netdev_priv(bond_dev);
+}
+
+static void __bond_netpoll_cleanup(struct bonding *bond)
+{
         struct slave *slave;
         int i;
 
-        bond_for_each_slave(bond, slave, i) {
-                if (slave->dev && IS_UP(slave->dev))
-                        netpoll_poll_dev(slave->dev);
-        }
+        bond_for_each_slave(bond, slave, i)
+                if (IS_UP(slave->dev))
+                        slave_disable_netpoll(slave);
 }
-
 static void bond_netpoll_cleanup(struct net_device *bond_dev)
 {
         struct bonding *bond = netdev_priv(bond_dev);
+
+        read_lock(&bond->lock);
+        __bond_netpoll_cleanup(bond);
+        read_unlock(&bond->lock);
+}
+
+static int bond_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
+{
+        struct bonding *bond = netdev_priv(dev);
         struct slave *slave;
-        const struct net_device_ops *ops;
-        int i;
+        int i, err = 0;
 
         read_lock(&bond->lock);
-        bond_dev->npinfo = NULL;
         bond_for_each_slave(bond, slave, i) {
-                if (slave->dev) {
-                        ops = slave->dev->netdev_ops;
-                        if (ops->ndo_netpoll_cleanup)
-                                ops->ndo_netpoll_cleanup(slave->dev);
-                        else
-                                slave->dev->npinfo = NULL;
+                if (!IS_UP(slave->dev))
+                        continue;
+                err = slave_enable_netpoll(slave);
+                if (err) {
+                        __bond_netpoll_cleanup(bond);
+                        break;
                 }
         }
         read_unlock(&bond->lock);
+        return err;
 }
 
-#else
+static struct netpoll_info *bond_netpoll_info(struct bonding *bond)
+{
+        return bond->dev->npinfo;
+}
 
+#else
+static inline int slave_enable_netpoll(struct slave *slave)
+{
+        return 0;
+}
+static inline void slave_disable_netpoll(struct slave *slave)
+{
+}
 static void bond_netpoll_cleanup(struct net_device *bond_dev)
 {
 }
-
+static int bond_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
+{
+        return 0;
+}
+static struct netpoll_info *bond_netpoll_info(struct bonding *bond)
+{
+        return NULL;
+}
 #endif
 
 /*---------------------------------- IOCTL ----------------------------------*/
@@ -1782,17 +1827,19 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
         bond_set_carrier(bond);
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
-        if (slaves_support_netpoll(bond_dev)) {
-                bond_dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
-                if (bond_dev->npinfo)
-                        slave_dev->npinfo = bond_dev->npinfo;
-        } else if (!(bond_dev->priv_flags & IFF_DISABLE_NETPOLL)) {
-                bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
-                pr_info("New slave device %s does not support netpoll\n",
-                        slave_dev->name);
-                pr_info("Disabling netpoll support for %s\n", bond_dev->name);
+        slave_dev->npinfo = bond_netpoll_info(bond);
+        if (slave_dev->npinfo) {
+                if (slave_enable_netpoll(new_slave)) {
+                        read_unlock(&bond->lock);
+                        pr_info("Error, %s: master_dev is using netpoll, "
+                                 "but new slave device does not support netpoll.\n",
+                                 bond_dev->name);
+                        res = -EBUSY;
+                        goto err_close;
+                }
         }
 #endif
+
         read_unlock(&bond->lock);
 
         res = bond_create_slave_symlinks(bond_dev, slave_dev);
@@ -1994,17 +2041,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
 
         netdev_set_bond_master(slave_dev, NULL);
 
-#ifdef CONFIG_NET_POLL_CONTROLLER
-        read_lock_bh(&bond->lock);
-
-        if (slaves_support_netpoll(bond_dev))
-                bond_dev->priv_flags &= ~IFF_DISABLE_NETPOLL;
-        read_unlock_bh(&bond->lock);
-        if (slave_dev->netdev_ops->ndo_netpoll_cleanup)
-                slave_dev->netdev_ops->ndo_netpoll_cleanup(slave_dev);
-        else
-                slave_dev->npinfo = NULL;
-#endif
+        slave_disable_netpoll(slave);
 
         /* close slave before restoring its mac address */
         dev_close(slave_dev);
@@ -2039,6 +2076,7 @@ static int  bond_release_and_destroy(struct net_device *bond_dev,
 
         ret = bond_release(bond_dev, slave_dev);
         if ((ret == 0) && (bond->slave_cnt == 0)) {
+                bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
                 pr_info("%s: destroying bond %s.\n",
                         bond_dev->name, bond_dev->name);
                 unregister_netdevice(bond_dev);
@@ -2116,6 +2154,8 @@ static int bond_release_all(struct net_device *bond_dev)
 
                 netdev_set_bond_master(slave_dev, NULL);
 
+                slave_disable_netpoll(slave);
+
                 /* close slave before restoring its mac address */
                 dev_close(slave_dev);
 
@@ -4654,6 +4694,7 @@ static const struct net_device_ops bond_netdev_ops = {
         .ndo_vlan_rx_add_vid    = bond_vlan_rx_add_vid,
         .ndo_vlan_rx_kill_vid   = bond_vlan_rx_kill_vid,
 #ifdef CONFIG_NET_POLL_CONTROLLER
+        .ndo_netpoll_setup      = bond_netpoll_setup,
         .ndo_netpoll_cleanup    = bond_netpoll_cleanup,
         .ndo_poll_controller    = bond_poll_controller,
 #endif
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 31fe980e4e28..0a3e00b220b7 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -20,6 +20,7 @@
 #include <linux/if_bonding.h>
 #include <linux/cpumask.h>
 #include <linux/in6.h>
+#include <linux/netpoll.h>
 #include "bond_3ad.h"
 #include "bond_alb.h"
 
@@ -198,6 +199,9 @@ struct slave {
         u16    queue_id;
         struct ad_slave_info ad_info; /* HUGE - better to dynamically alloc */
         struct tlb_slave_info tlb_info;
+#ifdef CONFIG_NET_POLL_CONTROLLER
+        struct netpoll *np;
+#endif
 };
 
 /*
@@ -323,6 +327,22 @@ static inline unsigned long slave_last_rx(struct bonding *bond,
         return slave->dev->last_rx;
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static inline void bond_netpoll_send_skb(const struct slave *slave,
+                                         struct sk_buff *skb)
+{
+        struct netpoll *np = slave->np;
+
+        if (np)
+                netpoll_send_skb(np, skb);
+}
+#else
+static inline void bond_netpoll_send_skb(const struct slave *slave,
+                                         struct sk_buff *skb)
+{
+}
+#endif
+
 static inline void bond_set_slave_inactive_flags(struct slave *slave)
 {
         struct bonding *bond = netdev_priv(slave->dev->master);