xref: /linux-6.15/include/linux/netpoll.h (revision 4bedea94)
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>
12 #include <linux/list.h>
13 
14 struct netpoll;
15 
16 struct netpoll {
17 	struct net_device *dev;
18 	char dev_name[16], *name;
19 	void (*rx_hook)(struct netpoll *, int, char *, int);
20 	void (*drop)(struct sk_buff *skb);
21 	u32 local_ip, remote_ip;
22 	u16 local_port, remote_port;
23 	unsigned char local_mac[6], remote_mac[6];
24 };
25 
26 struct netpoll_info {
27 	spinlock_t poll_lock;
28 	int poll_owner;
29 	int rx_flags;
30 	spinlock_t rx_lock;
31 	struct netpoll *rx_np; /* netpoll that registered an rx_hook */
32 };
33 
34 void netpoll_poll(struct netpoll *np);
35 void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
36 int netpoll_parse_options(struct netpoll *np, char *opt);
37 int netpoll_setup(struct netpoll *np);
38 int netpoll_trap(void);
39 void netpoll_set_trap(int trap);
40 void netpoll_cleanup(struct netpoll *np);
41 int __netpoll_rx(struct sk_buff *skb);
42 void netpoll_queue(struct sk_buff *skb);
43 
44 #ifdef CONFIG_NETPOLL
45 static inline int netpoll_rx(struct sk_buff *skb)
46 {
47 	struct netpoll_info *npinfo = skb->dev->npinfo;
48 	unsigned long flags;
49 	int ret = 0;
50 
51 	if (!npinfo || (!npinfo->rx_np && !npinfo->rx_flags))
52 		return 0;
53 
54 	spin_lock_irqsave(&npinfo->rx_lock, flags);
55 	/* check rx_flags again with the lock held */
56 	if (npinfo->rx_flags && __netpoll_rx(skb))
57 		ret = 1;
58 	spin_unlock_irqrestore(&npinfo->rx_lock, flags);
59 
60 	return ret;
61 }
62 
63 static inline void netpoll_poll_lock(struct net_device *dev)
64 {
65 	if (dev->npinfo) {
66 		spin_lock(&dev->npinfo->poll_lock);
67 		dev->npinfo->poll_owner = smp_processor_id();
68 	}
69 }
70 
71 static inline void netpoll_poll_unlock(struct net_device *dev)
72 {
73 	if (dev->npinfo) {
74 		dev->npinfo->poll_owner = -1;
75 		spin_unlock(&dev->npinfo->poll_lock);
76 	}
77 }
78 
79 #else
80 #define netpoll_rx(a) 0
81 #define netpoll_poll_lock(a)
82 #define netpoll_poll_unlock(a)
83 #endif
84 
85 #endif
86