[linux-2.6-block.git] / 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/rcupdate.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);
	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 tries;
	int rx_flags;
	spinlock_t rx_lock;
	struct netpoll *rx_np; /* netpoll that registered an rx_hook */
	struct sk_buff_head arp_tx; /* list of arp requests to reply to */
};

void netpoll_poll(struct netpoll *np);
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);
void netpoll_queue(struct sk_buff *skb);

#ifdef CONFIG_NETPOLL
static inline int netpoll_rx(struct sk_buff *skb)
{
	struct netpoll_info *npinfo = skb->dev->npinfo;
	unsigned long flags;
	int ret = 0;

	if (!npinfo || (!npinfo->rx_np && !npinfo->rx_flags))
		return 0;

	spin_lock_irqsave(&npinfo->rx_lock, flags);
	/* check rx_flags again with the lock held */
	if (npinfo->rx_flags && __netpoll_rx(skb))
		ret = 1;
	spin_unlock_irqrestore(&npinfo->rx_lock, flags);

	return ret;
}

static inline void *netpoll_poll_lock(struct net_device *dev)
{
	rcu_read_lock(); /* deal with race on ->npinfo */
	if (dev->npinfo) {
		spin_lock(&dev->npinfo->poll_lock);
		dev->npinfo->poll_owner = smp_processor_id();
		return dev->npinfo;
	}
	return NULL;
}

static inline void netpoll_poll_unlock(void *have)
{
	struct netpoll_info *npi = have;

	if (npi) {
		npi->poll_owner = -1;
		spin_unlock(&npi->poll_lock);
	}
	rcu_read_unlock();
}

#else
#define netpoll_rx(a) 0
#define netpoll_poll_lock(a) NULL
#define netpoll_poll_unlock(a)
#endif

#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Common code for low-level network console, dump, and debugger code
	3	*
	4	* Derived from netconsole, kgdb-over-ethernet, and netdump patches
	5	*/
	6
	7	#ifndef _LINUX_NETPOLL_H
	8	#define _LINUX_NETPOLL_H
	9
	10	#include <linux/netdevice.h>
	11	#include <linux/interrupt.h>
53fb95d3	12	#include <linux/rcupdate.h>
1da177e4 LT	13	#include <linux/list.h>
	14
	15	struct netpoll;
	16
	17	struct netpoll {
	18	struct net_device *dev;
	19	char dev_name[16], *name;
1da177e4 LT	20	void (rx_hook)(struct netpoll , int, char *, int);
	21	void (drop)(struct sk_buff skb);
	22	u32 local_ip, remote_ip;
	23	u16 local_port, remote_port;
	24	unsigned char local_mac[6], remote_mac[6];
115c1d6e JM	25	};
	26
	27	struct netpoll_info {
1da177e4 LT	28	spinlock_t poll_lock;
1da177e4 LT	29	int poll_owner;
0db1d6fc	30	int tries;
115c1d6e	31	int rx_flags;
fbeec2e1 JM	32	spinlock_t rx_lock;
fbeec2e1 JM	33	struct netpoll rx_np; / netpoll that registered an rx_hook */
068c6e98	34	struct sk_buff_head arp_tx; /* list of arp requests to reply to */
1da177e4 LT	35	};
	36
	37	void netpoll_poll(struct netpoll *np);
	38	void netpoll_send_udp(struct netpoll np, const char msg, int len);
	39	int netpoll_parse_options(struct netpoll np, char opt);
	40	int netpoll_setup(struct netpoll *np);
	41	int netpoll_trap(void);
	42	void netpoll_set_trap(int trap);
	43	void netpoll_cleanup(struct netpoll *np);
	44	int __netpoll_rx(struct sk_buff *skb);
	45	void netpoll_queue(struct sk_buff *skb);
	46
	47	#ifdef CONFIG_NETPOLL
	48	static inline int netpoll_rx(struct sk_buff *skb)
	49	{
115c1d6e	50	struct netpoll_info *npinfo = skb->dev->npinfo;
fbeec2e1 JM	51	unsigned long flags;
fbeec2e1 JM	52	int ret = 0;
115c1d6e	53
fbeec2e1	54	if (!npinfo \|\| (!npinfo->rx_np && !npinfo->rx_flags))
115c1d6e JM	55	return 0;
115c1d6e JM	56
fbeec2e1 JM	57	spin_lock_irqsave(&npinfo->rx_lock, flags);
	58	/* check rx_flags again with the lock held */
	59	if (npinfo->rx_flags && __netpoll_rx(skb))
	60	ret = 1;
	61	spin_unlock_irqrestore(&npinfo->rx_lock, flags);
	62
	63	return ret;
1da177e4 LT	64	}
1da177e4 LT	65
53fb95d3	66	static inline void netpoll_poll_lock(struct net_device dev)
1da177e4	67	{
53fb95d3	68	rcu_read_lock(); /* deal with race on ->npinfo */
115c1d6e JM	69	if (dev->npinfo) {
	70	spin_lock(&dev->npinfo->poll_lock);
	71	dev->npinfo->poll_owner = smp_processor_id();
53fb95d3	72	return dev->npinfo;
1da177e4	73	}
53fb95d3	74	return NULL;
1da177e4 LT	75	}
1da177e4 LT	76
53fb95d3	77	static inline void netpoll_poll_unlock(void *have)
1da177e4	78	{
53fb95d3 MM	79	struct netpoll_info *npi = have;
	80
	81	if (npi) {
	82	npi->poll_owner = -1;
	83	spin_unlock(&npi->poll_lock);
1da177e4	84	}
53fb95d3	85	rcu_read_unlock();
1da177e4 LT	86	}
	87
	88	#else
	89	#define netpoll_rx(a) 0
afb997c6	90	#define netpoll_poll_lock(a) NULL
1da177e4 LT	91	#define netpoll_poll_unlock(a)
	92	#endif
	93
	94	#endif