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/rcupdate.h> 13 #include <linux/list.h> 14 15 struct netpoll; 16 17 struct netpoll { 18 struct net_device *dev; 19 char dev_name[16], *name; 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]; 25 }; 26 27 struct netpoll_info { 28 spinlock_t poll_lock; 29 int poll_owner; 30 int tries; 31 int rx_flags; 32 spinlock_t rx_lock; 33 struct netpoll *rx_np; /* netpoll that registered an rx_hook */ 34 }; 35 36 void netpoll_poll(struct netpoll *np); 37 void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 38 int netpoll_parse_options(struct netpoll *np, char *opt); 39 int netpoll_setup(struct netpoll *np); 40 int netpoll_trap(void); 41 void netpoll_set_trap(int trap); 42 void netpoll_cleanup(struct netpoll *np); 43 int __netpoll_rx(struct sk_buff *skb); 44 void netpoll_queue(struct sk_buff *skb); 45 46 #ifdef CONFIG_NETPOLL 47 static inline int netpoll_rx(struct sk_buff *skb) 48 { 49 struct netpoll_info *npinfo = skb->dev->npinfo; 50 unsigned long flags; 51 int ret = 0; 52 53 if (!npinfo || (!npinfo->rx_np && !npinfo->rx_flags)) 54 return 0; 55 56 spin_lock_irqsave(&npinfo->rx_lock, flags); 57 /* check rx_flags again with the lock held */ 58 if (npinfo->rx_flags && __netpoll_rx(skb)) 59 ret = 1; 60 spin_unlock_irqrestore(&npinfo->rx_lock, flags); 61 62 return ret; 63 } 64 65 static inline void *netpoll_poll_lock(struct net_device *dev) 66 { 67 rcu_read_lock(); /* deal with race on ->npinfo */ 68 if (dev->npinfo) { 69 spin_lock(&dev->npinfo->poll_lock); 70 dev->npinfo->poll_owner = smp_processor_id(); 71 return dev->npinfo; 72 } 73 return NULL; 74 } 75 76 static inline void netpoll_poll_unlock(void *have) 77 { 78 struct netpoll_info *npi = have; 79 80 if (npi) { 81 npi->poll_owner = -1; 82 spin_unlock(&npi->poll_lock); 83 } 84 rcu_read_unlock(); 85 } 86 87 #else 88 #define netpoll_rx(a) 0 89 #define netpoll_poll_lock(a) NULL 90 #define netpoll_poll_unlock(a) 91 #endif 92 93 #endif 94