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 struct net_device *real_dev; 18 char dev_name[IFNAMSIZ]; 19 const char *name; 20 void (*rx_hook)(struct netpoll *, int, char *, int); 21 22 __be32 local_ip, remote_ip; 23 u16 local_port, remote_port; 24 u8 remote_mac[ETH_ALEN]; 25 26 struct list_head rx; /* rx_np list element */ 27 }; 28 29 struct netpoll_info { 30 atomic_t refcnt; 31 32 int rx_flags; 33 spinlock_t rx_lock; 34 struct list_head rx_np; /* netpolls that registered an rx_hook */ 35 36 struct sk_buff_head arp_tx; /* list of arp requests to reply to */ 37 struct sk_buff_head txq; 38 39 struct delayed_work tx_work; 40 41 struct netpoll *netpoll; 42 }; 43 44 void netpoll_poll_dev(struct net_device *dev); 45 void netpoll_poll(struct netpoll *np); 46 void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 47 void netpoll_print_options(struct netpoll *np); 48 int netpoll_parse_options(struct netpoll *np, char *opt); 49 int netpoll_setup(struct netpoll *np); 50 int netpoll_trap(void); 51 void netpoll_set_trap(int trap); 52 void netpoll_cleanup(struct netpoll *np); 53 int __netpoll_rx(struct sk_buff *skb); 54 void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb); 55 56 57 #ifdef CONFIG_NETPOLL 58 static inline bool netpoll_rx(struct sk_buff *skb) 59 { 60 struct netpoll_info *npinfo = skb->dev->npinfo; 61 unsigned long flags; 62 bool ret = false; 63 64 if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags)) 65 return false; 66 67 spin_lock_irqsave(&npinfo->rx_lock, flags); 68 /* check rx_flags again with the lock held */ 69 if (npinfo->rx_flags && __netpoll_rx(skb)) 70 ret = true; 71 spin_unlock_irqrestore(&npinfo->rx_lock, flags); 72 73 return ret; 74 } 75 76 static inline int netpoll_rx_on(struct sk_buff *skb) 77 { 78 struct netpoll_info *npinfo = skb->dev->npinfo; 79 80 return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags); 81 } 82 83 static inline int netpoll_receive_skb(struct sk_buff *skb) 84 { 85 if (!list_empty(&skb->dev->napi_list)) 86 return netpoll_rx(skb); 87 return 0; 88 } 89 90 static inline void *netpoll_poll_lock(struct napi_struct *napi) 91 { 92 struct net_device *dev = napi->dev; 93 94 rcu_read_lock(); /* deal with race on ->npinfo */ 95 if (dev && dev->npinfo) { 96 spin_lock(&napi->poll_lock); 97 napi->poll_owner = smp_processor_id(); 98 return napi; 99 } 100 return NULL; 101 } 102 103 static inline void netpoll_poll_unlock(void *have) 104 { 105 struct napi_struct *napi = have; 106 107 if (napi) { 108 napi->poll_owner = -1; 109 spin_unlock(&napi->poll_lock); 110 } 111 rcu_read_unlock(); 112 } 113 114 #else 115 static inline int netpoll_rx(struct sk_buff *skb) 116 { 117 return 0; 118 } 119 static inline int netpoll_rx_on(struct sk_buff *skb) 120 { 121 return 0; 122 } 123 static inline int netpoll_receive_skb(struct sk_buff *skb) 124 { 125 return 0; 126 } 127 static inline void *netpoll_poll_lock(struct napi_struct *napi) 128 { 129 return NULL; 130 } 131 static inline void netpoll_poll_unlock(void *have) 132 { 133 } 134 static inline void netpoll_netdev_init(struct net_device *dev) 135 { 136 } 137 #endif 138 139 #endif 140