1 files changed, 78 insertions, 31 deletions

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index b4c90e42b443..346b1eb83a1f 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -26,6 +26,7 @@
 #include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <linux/export.h>
+#include <linux/if_vlan.h>
 #include <net/tcp.h>
 #include <net/udp.h>
 #include <asm/unaligned.h>
@@ -54,7 +55,7 @@ static atomic_t trapped;
          MAX_UDP_CHUNK)
 
 static void zap_completion_queue(void);
-static void arp_reply(struct sk_buff *skb);
+static void netpoll_arp_reply(struct sk_buff *skb, struct netpoll_info *npinfo);
 
 static unsigned int carrier_timeout = 4;
 module_param(carrier_timeout, uint, 0644);
@@ -167,15 +168,24 @@ static void poll_napi(struct net_device *dev)
         struct napi_struct *napi;
         int budget = 16;
 
+        WARN_ON_ONCE(!irqs_disabled());
+
         list_for_each_entry(napi, &dev->napi_list, dev_list) {
+                local_irq_enable();
                 if (napi->poll_owner != smp_processor_id() &&
                     spin_trylock(&napi->poll_lock)) {
-                        budget = poll_one_napi(dev->npinfo, napi, budget);
+                        rcu_read_lock_bh();
+                        budget = poll_one_napi(rcu_dereference_bh(dev->npinfo),
+                                               napi, budget);
+                        rcu_read_unlock_bh();
                         spin_unlock(&napi->poll_lock);
 
-                        if (!budget)
+                        if (!budget) {
+                                local_irq_disable();
                                 break;
+                        }
                 }
+                local_irq_disable();
         }
 }
 
@@ -185,13 +195,14 @@ static void service_arp_queue(struct netpoll_info *npi)
                 struct sk_buff *skb;
 
                 while ((skb = skb_dequeue(&npi->arp_tx)))
-                        arp_reply(skb);
+                        netpoll_arp_reply(skb, npi);
         }
 }
 
 static void netpoll_poll_dev(struct net_device *dev)
 {
         const struct net_device_ops *ops;
+        struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo);
 
         if (!dev || !netif_running(dev))
                 return;
@@ -206,17 +217,18 @@ static void netpoll_poll_dev(struct net_device *dev)
         poll_napi(dev);
 
         if (dev->flags & IFF_SLAVE) {
-                if (dev->npinfo) {
+                if (ni) {
                         struct net_device *bond_dev = dev->master;
                         struct sk_buff *skb;
-                        while ((skb = skb_dequeue(&dev->npinfo->arp_tx))) {
+                        struct netpoll_info *bond_ni = rcu_dereference_bh(bond_dev->npinfo);
+                        while ((skb = skb_dequeue(&ni->arp_tx))) {
                                 skb->dev = bond_dev;
-                                skb_queue_tail(&bond_dev->npinfo->arp_tx, skb);
+                                skb_queue_tail(&bond_ni->arp_tx, skb);
                         }
                 }
         }
 
-        service_arp_queue(dev->npinfo);
+        service_arp_queue(ni);
 
         zap_completion_queue();
 }
@@ -302,6 +314,7 @@ static int netpoll_owner_active(struct net_device *dev)
         return 0;
 }
 
+/* call with IRQ disabled */
 void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
                              struct net_device *dev)
 {
@@ -309,8 +322,11 @@ void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
         unsigned long tries;
         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;
+        struct netpoll_info *npinfo;
+
+        WARN_ON_ONCE(!irqs_disabled());
 
+        npinfo = rcu_dereference_bh(np->dev->npinfo);
         if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
                 __kfree_skb(skb);
                 return;
@@ -319,16 +335,22 @@ void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
         /* don't get messages out of order, and no recursion */
         if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) {
                 struct netdev_queue *txq;
-                unsigned long flags;
 
                 txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
 
-                local_irq_save(flags);
                 /* try until next clock tick */
                 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
                      tries > 0; --tries) {
                         if (__netif_tx_trylock(txq)) {
                                 if (!netif_xmit_stopped(txq)) {
+                                        if (vlan_tx_tag_present(skb) &&
+                                            !(netif_skb_features(skb) & NETIF_F_HW_VLAN_TX)) {
+                                                skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
+                                                if (unlikely(!skb))
+                                                        break;
+                                                skb->vlan_tci = 0;
+                                        }
+
                                         status = ops->ndo_start_xmit(skb, dev);
                                         if (status == NETDEV_TX_OK)
                                                 txq_trans_update(txq);
@@ -347,10 +369,9 @@ void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
                 }
 
                 WARN_ONCE(!irqs_disabled(),
-                        "netpoll_send_skb(): %s enabled interrupts in poll (%pF)\n",
+                        "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pF)\n",
                         dev->name, ops->ndo_start_xmit);
 
-                local_irq_restore(flags);
         }
 
         if (status != NETDEV_TX_OK) {
@@ -423,9 +444,8 @@ void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
 }
 EXPORT_SYMBOL(netpoll_send_udp);
 
-static void arp_reply(struct sk_buff *skb)
+static void netpoll_arp_reply(struct sk_buff *skb, struct netpoll_info *npinfo)
 {
-        struct netpoll_info *npinfo = skb->dev->npinfo;
         struct arphdr *arp;
         unsigned char *arp_ptr;
         int size, type = ARPOP_REPLY, ptype = ETH_P_ARP;
@@ -543,13 +563,12 @@ static void arp_reply(struct sk_buff *skb)
         spin_unlock_irqrestore(&npinfo->rx_lock, flags);
 }
 
-int __netpoll_rx(struct sk_buff *skb)
+int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo)
 {
         int proto, len, ulen;
         int hits = 0;
         const struct iphdr *iph;
         struct udphdr *uh;
-        struct netpoll_info *npinfo = skb->dev->npinfo;
         struct netpoll *np, *tmp;
 
         if (list_empty(&npinfo->rx_np))
@@ -565,6 +584,12 @@ int __netpoll_rx(struct sk_buff *skb)
                 return 1;
         }
 
+        if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
+                skb = vlan_untag(skb);
+                if (unlikely(!skb))
+                        goto out;
+        }
+
         proto = ntohs(eth_hdr(skb)->h_proto);
         if (proto != ETH_P_IP)
                 goto out;
@@ -715,7 +740,7 @@ int netpoll_parse_options(struct netpoll *np, char *opt)
 }
 EXPORT_SYMBOL(netpoll_parse_options);
 
-int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
+int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp)
 {
         struct netpoll_info *npinfo;
         const struct net_device_ops *ops;
@@ -734,7 +759,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
         }
 
         if (!ndev->npinfo) {
-                npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
+                npinfo = kmalloc(sizeof(*npinfo), gfp);
                 if (!npinfo) {
                         err = -ENOMEM;
                         goto out;
@@ -752,7 +777,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
 
                 ops = np->dev->netdev_ops;
                 if (ops->ndo_netpoll_setup) {
-                        err = ops->ndo_netpoll_setup(ndev, npinfo);
+                        err = ops->ndo_netpoll_setup(ndev, npinfo, gfp);
                         if (err)
                                 goto free_npinfo;
                 }
@@ -857,7 +882,7 @@ int netpoll_setup(struct netpoll *np)
         refill_skbs();
 
         rtnl_lock();
-        err = __netpoll_setup(np, ndev);
+        err = __netpoll_setup(np, ndev, GFP_KERNEL);
         rtnl_unlock();
 
         if (err)
@@ -878,6 +903,24 @@ static int __init netpoll_init(void)
 }
 core_initcall(netpoll_init);
 
+static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head)
+{
+        struct netpoll_info *npinfo =
+                        container_of(rcu_head, struct netpoll_info, rcu);
+
+        skb_queue_purge(&npinfo->arp_tx);
+        skb_queue_purge(&npinfo->txq);
+
+        /* we can't call cancel_delayed_work_sync here, as we are in softirq */
+        cancel_delayed_work(&npinfo->tx_work);
+
+        /* clean after last, unfinished work */
+        __skb_queue_purge(&npinfo->txq);
+        /* now cancel it again */
+        cancel_delayed_work(&npinfo->tx_work);
+        kfree(npinfo);
+}
+
 void __netpoll_cleanup(struct netpoll *np)
 {
         struct netpoll_info *npinfo;
@@ -903,20 +946,24 @@ void __netpoll_cleanup(struct netpoll *np)
                         ops->ndo_netpoll_cleanup(np->dev);
 
                 RCU_INIT_POINTER(np->dev->npinfo, NULL);
+                call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info);
+        }
+}
+EXPORT_SYMBOL_GPL(__netpoll_cleanup);
 
-                /* avoid racing with NAPI reading npinfo */
-                synchronize_rcu_bh();
+static void rcu_cleanup_netpoll(struct rcu_head *rcu_head)
+{
+        struct netpoll *np = container_of(rcu_head, struct netpoll, rcu);
 
-                skb_queue_purge(&npinfo->arp_tx);
-                skb_queue_purge(&npinfo->txq);
-                cancel_delayed_work_sync(&npinfo->tx_work);
+        __netpoll_cleanup(np);
+        kfree(np);
+}
 
-                /* clean after last, unfinished work */
-                __skb_queue_purge(&npinfo->txq);
-                kfree(npinfo);
-        }
+void __netpoll_free_rcu(struct netpoll *np)
+{
+        call_rcu_bh(&np->rcu, rcu_cleanup_netpoll);
 }
-EXPORT_SYMBOL_GPL(__netpoll_cleanup);
+EXPORT_SYMBOL_GPL(__netpoll_free_rcu);
 
 void netpoll_cleanup(struct netpoll *np)
 {