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 struct net_device *dev; 17 char dev_name[IFNAMSIZ]; 18 const char *name; 19 void (*rx_hook)(struct netpoll *, int, char *, int); 20 21 __be32 local_ip, remote_ip; 22 u16 local_port, remote_port; 23 u8 remote_mac[ETH_ALEN]; 24 }; 25 26 struct netpoll_info { 27 atomic_t refcnt; 28 int rx_flags; 29 spinlock_t rx_lock; 30 struct netpoll *rx_np; /* netpoll that registered an rx_hook */ 31 struct sk_buff_head arp_tx; /* list of arp requests to reply to */ 32 struct sk_buff_head txq; 33 struct delayed_work tx_work; 34 }; 35 36 void netpoll_poll(struct netpoll *np); 37 void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 38 void netpoll_print_options(struct netpoll *np); 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 46 47 #ifdef CONFIG_NETPOLL 48 static inline int netpoll_rx(struct sk_buff *skb) 49 { 50 struct netpoll_info *npinfo = skb->dev->npinfo; 51 unsigned long flags; 52 int ret = 0; 53 54 if (!npinfo || (!npinfo->rx_np && !npinfo->rx_flags)) 55 return 0; 56 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; 64 } 65 66 static inline int netpoll_rx_on(struct sk_buff *skb) 67 { 68 struct netpoll_info *npinfo = skb->dev->npinfo; 69 70 return npinfo && (npinfo->rx_np || npinfo->rx_flags); 71 } 72 73 static inline int netpoll_receive_skb(struct sk_buff *skb) 74 { 75 if (!list_empty(&skb->dev->napi_list)) 76 return netpoll_rx(skb); 77 return 0; 78 } 79 80 static inline void *netpoll_poll_lock(struct napi_struct *napi) 81 { 82 struct net_device *dev = napi->dev; 83 84 rcu_read_lock(); /* deal with race on ->npinfo */ 85 if (dev && dev->npinfo) { 86 spin_lock(&napi->poll_lock); 87 napi->poll_owner = smp_processor_id(); 88 return napi; 89 } 90 return NULL; 91 } 92 93 static inline void netpoll_poll_unlock(void *have) 94 { 95 struct napi_struct *napi = have; 96 97 if (napi) { 98 napi->poll_owner = -1; 99 spin_unlock(&napi->poll_lock); 100 } 101 rcu_read_unlock(); 102 } 103 104 #else 105 static inline int netpoll_rx(struct sk_buff *skb) 106 { 107 return 0; 108 } 109 static inline int netpoll_rx_on(struct sk_buff *skb) 110 { 111 return 0; 112 } 113 static inline int netpoll_receive_skb(struct sk_buff *skb) 114 { 115 return 0; 116 } 117 static inline void *netpoll_poll_lock(struct napi_struct *napi) 118 { 119 return NULL; 120 } 121 static inline void netpoll_poll_unlock(void *have) 122 { 123 } 124 static inline void netpoll_netdev_init(struct net_device *dev) 125 { 126 } 127 #endif 128 129 #endif 130