1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Common code for low-level network console, dump, and debugger code
4  *
5  * Derived from netconsole, kgdb-over-ethernet, and netdump patches
6  */
7 
8 #ifndef _LINUX_NETPOLL_H
9 #define _LINUX_NETPOLL_H
10 
11 #include <linux/netdevice.h>
12 #include <linux/interrupt.h>
13 #include <linux/rcupdate.h>
14 #include <linux/list.h>
15 #include <linux/refcount.h>
16 
17 union inet_addr {
18 	__u32		all[4];
19 	__be32		ip;
20 	__be32		ip6[4];
21 	struct in_addr	in;
22 	struct in6_addr	in6;
23 };
24 
25 struct netpoll {
26 	struct net_device *dev;
27 	netdevice_tracker dev_tracker;
28 	char dev_name[IFNAMSIZ];
29 	const char *name;
30 
31 	union inet_addr local_ip, remote_ip;
32 	bool ipv6;
33 	u16 local_port, remote_port;
34 	u8 remote_mac[ETH_ALEN];
35 };
36 
37 struct netpoll_info {
38 	refcount_t refcnt;
39 
40 	struct semaphore dev_lock;
41 
42 	struct sk_buff_head txq;
43 
44 	struct delayed_work tx_work;
45 
46 	struct netpoll *netpoll;
47 	struct rcu_head rcu;
48 };
49 
50 #ifdef CONFIG_NETPOLL
51 void netpoll_poll_dev(struct net_device *dev);
52 void netpoll_poll_disable(struct net_device *dev);
53 void netpoll_poll_enable(struct net_device *dev);
54 #else
netpoll_poll_disable(struct net_device * dev)55 static inline void netpoll_poll_disable(struct net_device *dev) { return; }
netpoll_poll_enable(struct net_device * dev)56 static inline void netpoll_poll_enable(struct net_device *dev) { return; }
57 #endif
58 
59 void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
60 void netpoll_print_options(struct netpoll *np);
61 int netpoll_parse_options(struct netpoll *np, char *opt);
62 int __netpoll_setup(struct netpoll *np, struct net_device *ndev);
63 int netpoll_setup(struct netpoll *np);
64 void __netpoll_cleanup(struct netpoll *np);
65 void __netpoll_free(struct netpoll *np);
66 void netpoll_cleanup(struct netpoll *np);
67 netdev_tx_t netpoll_send_skb(struct netpoll *np, struct sk_buff *skb);
68 
69 #ifdef CONFIG_NETPOLL
netpoll_poll_lock(struct napi_struct * napi)70 static inline void *netpoll_poll_lock(struct napi_struct *napi)
71 {
72 	struct net_device *dev = napi->dev;
73 
74 	if (dev && dev->npinfo) {
75 		int owner = smp_processor_id();
76 
77 		while (cmpxchg(&napi->poll_owner, -1, owner) != -1)
78 			cpu_relax();
79 
80 		return napi;
81 	}
82 	return NULL;
83 }
84 
netpoll_poll_unlock(void * have)85 static inline void netpoll_poll_unlock(void *have)
86 {
87 	struct napi_struct *napi = have;
88 
89 	if (napi)
90 		smp_store_release(&napi->poll_owner, -1);
91 }
92 
netpoll_tx_running(struct net_device * dev)93 static inline bool netpoll_tx_running(struct net_device *dev)
94 {
95 	return irqs_disabled();
96 }
97 
98 #else
netpoll_poll_lock(struct napi_struct * napi)99 static inline void *netpoll_poll_lock(struct napi_struct *napi)
100 {
101 	return NULL;
102 }
netpoll_poll_unlock(void * have)103 static inline void netpoll_poll_unlock(void *have)
104 {
105 }
netpoll_tx_running(struct net_device * dev)106 static inline bool netpoll_tx_running(struct net_device *dev)
107 {
108 	return false;
109 }
110 #endif
111 
112 #endif
113