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Diffstat (limited to 'net/core/netpoll.c')
-rw-r--r--net/core/netpoll.c40
1 files changed, 40 insertions, 0 deletions
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 331ccb90f915..edcd9ad95304 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -47,6 +47,8 @@ static struct sk_buff_head skb_pool;
static atomic_t trapped;
+static struct srcu_struct netpoll_srcu;
+
#define USEC_PER_POLL 50
#define NETPOLL_RX_ENABLED 1
#define NETPOLL_RX_DROP 2
@@ -199,6 +201,13 @@ static void netpoll_poll_dev(struct net_device *dev)
const struct net_device_ops *ops;
struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo);
+ /* Don't do any rx activity if the dev_lock mutex is held
+ * the dev_open/close paths use this to block netpoll activity
+ * while changing device state
+ */
+ if (!mutex_trylock(&dev->npinfo->dev_lock))
+ return;
+
if (!dev || !netif_running(dev))
return;
@@ -211,6 +220,8 @@ static void netpoll_poll_dev(struct net_device *dev)
poll_napi(dev);
+ mutex_unlock(&dev->npinfo->dev_lock);
+
if (dev->flags & IFF_SLAVE) {
if (ni) {
struct net_device *bond_dev;
@@ -231,6 +242,31 @@ static void netpoll_poll_dev(struct net_device *dev)
zap_completion_queue();
}
+int netpoll_rx_disable(struct net_device *dev)
+{
+ struct netpoll_info *ni;
+ int idx;
+ might_sleep();
+ idx = srcu_read_lock(&netpoll_srcu);
+ ni = srcu_dereference(dev->npinfo, &netpoll_srcu);
+ if (ni)
+ mutex_lock(&ni->dev_lock);
+ srcu_read_unlock(&netpoll_srcu, idx);
+ return 0;
+}
+EXPORT_SYMBOL(netpoll_rx_disable);
+
+void netpoll_rx_enable(struct net_device *dev)
+{
+ struct netpoll_info *ni;
+ rcu_read_lock();
+ ni = rcu_dereference(dev->npinfo);
+ if (ni)
+ mutex_unlock(&ni->dev_lock);
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(netpoll_rx_enable);
+
static void refill_skbs(void)
{
struct sk_buff *skb;
@@ -1004,6 +1040,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp)
INIT_LIST_HEAD(&npinfo->rx_np);
spin_lock_init(&npinfo->rx_lock);
+ mutex_init(&npinfo->dev_lock);
skb_queue_head_init(&npinfo->neigh_tx);
skb_queue_head_init(&npinfo->txq);
INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
@@ -1169,6 +1206,7 @@ EXPORT_SYMBOL(netpoll_setup);
static int __init netpoll_init(void)
{
skb_queue_head_init(&skb_pool);
+ init_srcu_struct(&netpoll_srcu);
return 0;
}
core_initcall(netpoll_init);
@@ -1208,6 +1246,8 @@ void __netpoll_cleanup(struct netpoll *np)
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
}
+ synchronize_srcu(&netpoll_srcu);
+
if (atomic_dec_and_test(&npinfo->refcnt)) {
const struct net_device_ops *ops;