[NETPOLL]: Introduce a netpoll_info struct

This patch introduces a netpoll_info structure, which the struct net_device
will now point to instead of pointing to a struct netpoll.  The reason for
this is two-fold: 1) fields such as the rx_flags, poll_owner, and poll_lock
should be maintained per net_device, not per netpoll;  and 2) this is a first
step in providing support for multiple netpoll clients to register against the
same net_device.

The struct netpoll is now pointed to by the netpoll_info structure.  As
such, the previous behaviour of the code is preserved.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 8 deletions

diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h
index 449a4fde658..388cd91bc7a 100644
--- a/include/linux/netpoll.h
+++ b/include/linux/netpoll.h
@@ -16,14 +16,18 @@ struct netpoll;
 struct netpoll {
 	struct net_device *dev;
 	char dev_name[16], *name;
-	int rx_flags;
 	void (*rx_hook)(struct netpoll *, int, char *, int);
 	void (*drop)(struct sk_buff *skb);
 	u32 local_ip, remote_ip;
 	u16 local_port, remote_port;
 	unsigned char local_mac[6], remote_mac[6];
+};
+
+struct netpoll_info {
 	spinlock_t poll_lock;
 	int poll_owner;
+	int rx_flags;
+	struct netpoll *np;
 };
 
 void netpoll_poll(struct netpoll *np);
@@ -39,22 +43,27 @@ void netpoll_queue(struct sk_buff *skb);
 #ifdef CONFIG_NETPOLL
 static inline int netpoll_rx(struct sk_buff *skb)
 {
-	return skb->dev->np && skb->dev->np->rx_flags && __netpoll_rx(skb);
+	struct netpoll_info *npinfo = skb->dev->npinfo;
+
+	if (!npinfo || !npinfo->rx_flags)
+		return 0;
+
+	return npinfo->np && __netpoll_rx(skb);
 }
 
 static inline void netpoll_poll_lock(struct net_device *dev)
 {
-	if (dev->np) {
-		spin_lock(&dev->np->poll_lock);
-		dev->np->poll_owner = smp_processor_id();
+	if (dev->npinfo) {
+		spin_lock(&dev->npinfo->poll_lock);
+		dev->npinfo->poll_owner = smp_processor_id();
 	}
 }
 
 static inline void netpoll_poll_unlock(struct net_device *dev)
 {
-	if (dev->np) {
-		dev->np->poll_owner = -1;
-		spin_unlock(&dev->np->poll_lock);
+	if (dev->npinfo) {
+		dev->npinfo->poll_owner = -1;
+		spin_unlock(&dev->npinfo->poll_lock);
 	}
 }