[NET] add netpoll API

include/linux/netdevice.h

@@ -452,6 +452,12 @@ struct net_device
 						     unsigned char *haddr);
 	int			(*neigh_setup)(struct net_device *dev, struct neigh_parms *);
 	int			(*accept_fastpath)(struct net_device *, struct dst_entry*);
+#ifdef CONFIG_NETPOLL_RX
+	int			netpoll_rx;
+#endif
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	void                    (*poll_controller)(struct net_device *dev);
+#endif
 
 	/* bridge stuff */
 	struct net_bridge_port	*br_port;
@@ -533,6 +539,9 @@ extern int		dev_new_index(void);
 extern struct net_device	*dev_get_by_index(int ifindex);
 extern struct net_device	*__dev_get_by_index(int ifindex);
 extern int		dev_restart(struct net_device *dev);
+#ifdef CONFIG_NETPOLL_TRAP
+extern int		netpoll_trap(void);
+#endif
 
 typedef int gifconf_func_t(struct net_device * dev, char * bufptr, int len);
 extern int		register_gifconf(unsigned int family, gifconf_func_t * gifconf);
@@ -591,12 +600,20 @@ static inline void netif_start_queue(struct net_device *dev)
 
 static inline void netif_wake_queue(struct net_device *dev)
 {
+#ifdef CONFIG_NETPOLL_TRAP
+	if (netpoll_trap())
+		return;
+#endif
 	if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state))
 		__netif_schedule(dev);
 }
 
 static inline void netif_stop_queue(struct net_device *dev)
 {
+#ifdef CONFIG_NETPOLL_TRAP
+	if (netpoll_trap())
+		return;
+#endif
 	set_bit(__LINK_STATE_XOFF, &dev->state);
 }
 

include/linux/netpoll.h

+/*
+ * Common code for low-level network console, dump, and debugger code
+ *
+ * Derived from netconsole, kgdb-over-ethernet, and netdump patches
+ */
+
+#ifndef _LINUX_NETPOLL_H
+#define _LINUX_NETPOLL_H
+
+#include <linux/netdevice.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/list.h>
+
+struct netpoll;
+
+struct netpoll {
+	struct net_device *dev;
+	char dev_name[16], *name;
+	void (*rx_hook)(struct netpoll *, int, char *, int);
+	u32 local_ip, remote_ip;
+	u16 local_port, remote_port;
+	unsigned char local_mac[6], remote_mac[6];
+	struct list_head rx_list;
+};
+
+void netpoll_poll(struct netpoll *np);
+void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb);
+void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
+int netpoll_parse_options(struct netpoll *np, char *opt);
+int netpoll_setup(struct netpoll *np);
+int netpoll_trap(void);
+void netpoll_set_trap(int trap);
+void netpoll_cleanup(struct netpoll *np);
+int netpoll_rx(struct sk_buff *skb);
+
+
+#endif

net/Kconfig

@@ -664,4 +664,18 @@ source "net/irda/Kconfig"
 
 source "net/bluetooth/Kconfig"
 
+config NETPOLL
+	bool "Netpoll API"
+
+config NETPOLL_RX
+	bool "Netpoll receive hooks"
+	depends on NETPOLL
+
+config NETPOLL_TRAP
+	bool "Netpoll traffic trapping"
+	depends on NETPOLL
+
+config NET_POLL_CONTROLLER
+	def_bool NETPOLL
+
 endmenu

net/core/Makefile

@@ -13,3 +13,4 @@ obj-$(CONFIG_NETFILTER) += netfilter.o
 obj-$(CONFIG_NET_DIVERT) += dv.o
 obj-$(CONFIG_NET_PKTGEN) += pktgen.o
 obj-$(CONFIG_NET_RADIO) += wireless.o
+obj-$(CONFIG_NETPOLL) += netpoll.o

net/core/dev.c

@@ -105,6 +105,7 @@
 #include <linux/kmod.h>
 #include <linux/module.h>
 #include <linux/kallsyms.h>
+#include <linux/netpoll.h>
 #ifdef CONFIG_NET_RADIO
 #include <linux/wireless.h>		/* Note : will define WIRELESS_EXT */
 #include <net/iw_handler.h>
@@ -1405,6 +1406,13 @@ int netif_rx(struct sk_buff *skb)
 	struct softnet_data *queue;
 	unsigned long flags;
 
+#ifdef CONFIG_NETPOLL_RX
+	if (skb->dev->netpoll_rx && netpoll_rx(skb)) {
+		kfree_skb(skb);
+		return NET_RX_DROP;
+	}
+#endif
+
 	if (!skb->stamp.tv_sec)
 		do_gettimeofday(&skb->stamp);
 
@@ -1560,6 +1568,13 @@ int netif_receive_skb(struct sk_buff *skb)
 	int ret = NET_RX_DROP;
 	unsigned short type = skb->protocol;
 
+#ifdef CONFIG_NETPOLL_RX
+	if (skb->dev->netpoll_rx && skb->dev->poll && netpoll_rx(skb)) {
+		kfree_skb(skb);
+		return NET_RX_DROP;
+	}
+#endif
+
 	if (!skb->stamp.tv_sec)
 		do_gettimeofday(&skb->stamp);