1 files changed, 106 insertions, 76 deletions

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 94825b109551..537e01afd81b 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -199,11 +199,13 @@ void netpoll_poll_dev(struct net_device *dev)
 
         zap_completion_queue();
 }
+EXPORT_SYMBOL(netpoll_poll_dev);
 
 void netpoll_poll(struct netpoll *np)
 {
         netpoll_poll_dev(np->dev);
 }
+EXPORT_SYMBOL(netpoll_poll);
 
 static void refill_skbs(void)
 {
@@ -292,6 +294,7 @@ void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
         unsigned long tries;
         struct net_device *dev = np->dev;
         const struct net_device_ops *ops = dev->netdev_ops;
+        /* It is up to the caller to keep npinfo alive. */
         struct netpoll_info *npinfo = np->dev->npinfo;
 
         if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
@@ -343,6 +346,7 @@ void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
                 schedule_delayed_work(&npinfo->tx_work,0);
         }
 }
+EXPORT_SYMBOL(netpoll_send_skb);
 
 void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
 {
@@ -404,6 +408,7 @@ void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
 
         netpoll_send_skb(np, skb);
 }
+EXPORT_SYMBOL(netpoll_send_udp);
 
 static void arp_reply(struct sk_buff *skb)
 {
@@ -630,6 +635,7 @@ void netpoll_print_options(struct netpoll *np)
         printk(KERN_INFO "%s: remote ethernet address %pM\n",
                          np->name, np->remote_mac);
 }
+EXPORT_SYMBOL(netpoll_print_options);
 
 int netpoll_parse_options(struct netpoll *np, char *opt)
 {
@@ -722,30 +728,29 @@ int netpoll_parse_options(struct netpoll *np, char *opt)
                np->name, cur);
         return -1;
 }
+EXPORT_SYMBOL(netpoll_parse_options);
 
-int netpoll_setup(struct netpoll *np)
+int __netpoll_setup(struct netpoll *np)
 {
-        struct net_device *ndev = NULL;
-        struct in_device *in_dev;
+        struct net_device *ndev = np->dev;
         struct netpoll_info *npinfo;
-        struct netpoll *npe, *tmp;
+        const struct net_device_ops *ops;
         unsigned long flags;
         int err;
 
-        if (np->dev_name)
-                ndev = dev_get_by_name(&init_net, np->dev_name);
-        if (!ndev) {
-                printk(KERN_ERR "%s: %s doesn't exist, aborting.\n",
+        if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
+            !ndev->netdev_ops->ndo_poll_controller) {
+                printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
                        np->name, np->dev_name);
-                return -ENODEV;
+                err = -ENOTSUPP;
+                goto out;
         }
 
-        np->dev = ndev;
         if (!ndev->npinfo) {
                 npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
                 if (!npinfo) {
                         err = -ENOMEM;
-                        goto put;
+                        goto out;
                 }
 
                 npinfo->rx_flags = 0;
@@ -757,6 +762,13 @@ int netpoll_setup(struct netpoll *np)
                 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
 
                 atomic_set(&npinfo->refcnt, 1);
+
+                ops = np->dev->netdev_ops;
+                if (ops->ndo_netpoll_setup) {
+                        err = ops->ndo_netpoll_setup(ndev, npinfo);
+                        if (err)
+                                goto free_npinfo;
+                }
         } else {
                 npinfo = ndev->npinfo;
                 atomic_inc(&npinfo->refcnt);
@@ -764,12 +776,37 @@ int netpoll_setup(struct netpoll *np)
 
         npinfo->netpoll = np;
 
-        if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
-            !ndev->netdev_ops->ndo_poll_controller) {
-                printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
+        if (np->rx_hook) {
+                spin_lock_irqsave(&npinfo->rx_lock, flags);
+                npinfo->rx_flags |= NETPOLL_RX_ENABLED;
+                list_add_tail(&np->rx, &npinfo->rx_np);
+                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
+        }
+
+        /* last thing to do is link it to the net device structure */
+        rcu_assign_pointer(ndev->npinfo, npinfo);
+
+        return 0;
+
+free_npinfo:
+        kfree(npinfo);
+out:
+        return err;
+}
+EXPORT_SYMBOL_GPL(__netpoll_setup);
+
+int netpoll_setup(struct netpoll *np)
+{
+        struct net_device *ndev = NULL;
+        struct in_device *in_dev;
+        int err;
+
+        if (np->dev_name)
+                ndev = dev_get_by_name(&init_net, np->dev_name);
+        if (!ndev) {
+                printk(KERN_ERR "%s: %s doesn't exist, aborting.\n",
                        np->name, np->dev_name);
-                err = -ENOTSUPP;
-                goto release;
+                return -ENODEV;
         }
 
         if (!netif_running(ndev)) {
@@ -785,7 +822,7 @@ int netpoll_setup(struct netpoll *np)
                 if (err) {
                         printk(KERN_ERR "%s: failed to open %s\n",
                                np->name, ndev->name);
-                        goto release;
+                        goto put;
                 }
 
                 atleast = jiffies + HZ/10;
@@ -822,7 +859,7 @@ int netpoll_setup(struct netpoll *np)
                         printk(KERN_ERR "%s: no IP address for %s, aborting\n",
                                np->name, np->dev_name);
                         err = -EDESTADDRREQ;
-                        goto release;
+                        goto put;
                 }
 
                 np->local_ip = in_dev->ifa_list->ifa_local;
@@ -830,38 +867,25 @@ int netpoll_setup(struct netpoll *np)
                 printk(KERN_INFO "%s: local IP %pI4\n", np->name, &np->local_ip);
         }
 
-        if (np->rx_hook) {
-                spin_lock_irqsave(&npinfo->rx_lock, flags);
-                npinfo->rx_flags |= NETPOLL_RX_ENABLED;
-                list_add_tail(&np->rx, &npinfo->rx_np);
-                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
-        }
+        np->dev = ndev;
 
         /* fill up the skb queue */
         refill_skbs();
 
-        /* last thing to do is link it to the net device structure */
-        ndev->npinfo = npinfo;
+        rtnl_lock();
+        err = __netpoll_setup(np);
+        rtnl_unlock();
 
-        /* avoid racing with NAPI reading npinfo */
-        synchronize_rcu();
+        if (err)
+                goto put;
 
         return 0;
 
- release:
-        if (!ndev->npinfo) {
-                spin_lock_irqsave(&npinfo->rx_lock, flags);
-                list_for_each_entry_safe(npe, tmp, &npinfo->rx_np, rx) {
-                        npe->dev = NULL;
-                }
-                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
-
-                kfree(npinfo);
-        }
 put:
         dev_put(ndev);
         return err;
 }
+EXPORT_SYMBOL(netpoll_setup);
 
 static int __init netpoll_init(void)
 {
@@ -870,49 +894,65 @@ static int __init netpoll_init(void)
 }
 core_initcall(netpoll_init);
 
-void netpoll_cleanup(struct netpoll *np)
+void __netpoll_cleanup(struct netpoll *np)
 {
         struct netpoll_info *npinfo;
         unsigned long flags;
 
-        if (np->dev) {
-                npinfo = np->dev->npinfo;
-                if (npinfo) {
-                        if (!list_empty(&npinfo->rx_np)) {
-                                spin_lock_irqsave(&npinfo->rx_lock, flags);
-                                list_del(&np->rx);
-                                if (list_empty(&npinfo->rx_np))
-                                        npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
-                                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
-                        }
+        npinfo = np->dev->npinfo;
+        if (!npinfo)
+                return;
 
-                        if (atomic_dec_and_test(&npinfo->refcnt)) {
-                                const struct net_device_ops *ops;
-                                skb_queue_purge(&npinfo->arp_tx);
-                                skb_queue_purge(&npinfo->txq);
-                                cancel_rearming_delayed_work(&npinfo->tx_work);
-
-                                /* clean after last, unfinished work */
-                                __skb_queue_purge(&npinfo->txq);
-                                kfree(npinfo);
-                                ops = np->dev->netdev_ops;
-                                if (ops->ndo_netpoll_cleanup)
-                                        ops->ndo_netpoll_cleanup(np->dev);
-                                else
-                                        np->dev->npinfo = NULL;
-                        }
-                }
+        if (!list_empty(&npinfo->rx_np)) {
+                spin_lock_irqsave(&npinfo->rx_lock, flags);
+                list_del(&np->rx);
+                if (list_empty(&npinfo->rx_np))
+                        npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
+                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
+        }
+
+        if (atomic_dec_and_test(&npinfo->refcnt)) {
+                const struct net_device_ops *ops;
+
+                ops = np->dev->netdev_ops;
+                if (ops->ndo_netpoll_cleanup)
+                        ops->ndo_netpoll_cleanup(np->dev);
+
+                rcu_assign_pointer(np->dev->npinfo, NULL);
+
+                /* avoid racing with NAPI reading npinfo */
+                synchronize_rcu_bh();
+
+                skb_queue_purge(&npinfo->arp_tx);
+                skb_queue_purge(&npinfo->txq);
+                cancel_rearming_delayed_work(&npinfo->tx_work);
 
-                dev_put(np->dev);
+                /* clean after last, unfinished work */
+                __skb_queue_purge(&npinfo->txq);
+                kfree(npinfo);
         }
+}
+EXPORT_SYMBOL_GPL(__netpoll_cleanup);
+
+void netpoll_cleanup(struct netpoll *np)
+{
+        if (!np->dev)
+                return;
 
+        rtnl_lock();
+        __netpoll_cleanup(np);
+        rtnl_unlock();
+
+        dev_put(np->dev);
         np->dev = NULL;
 }
+EXPORT_SYMBOL(netpoll_cleanup);
 
 int netpoll_trap(void)
 {
         return atomic_read(&trapped);
 }
+EXPORT_SYMBOL(netpoll_trap);
 
 void netpoll_set_trap(int trap)
 {
@@ -921,14 +961,4 @@ void netpoll_set_trap(int trap)
         else
                 atomic_dec(&trapped);
 }
-
-EXPORT_SYMBOL(netpoll_send_skb);
 EXPORT_SYMBOL(netpoll_set_trap);
-EXPORT_SYMBOL(netpoll_trap);
-EXPORT_SYMBOL(netpoll_print_options);
-EXPORT_SYMBOL(netpoll_parse_options);
-EXPORT_SYMBOL(netpoll_setup);
-EXPORT_SYMBOL(netpoll_cleanup);
-EXPORT_SYMBOL(netpoll_send_udp);
-EXPORT_SYMBOL(netpoll_poll_dev);
-EXPORT_SYMBOL(netpoll_poll);