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 struct list_head rx; /* rx_np list element */ 26 }; 27 28 struct netpoll_info { 29 atomic_t refcnt; 30 31 int rx_flags; 32 spinlock_t rx_lock; 33 struct list_head rx_np; /* netpolls that registered an rx_hook */ 34 35 struct sk_buff_head arp_tx; /* list of arp requests to reply to */ 36 struct sk_buff_head txq; 37 38 struct delayed_work tx_work; 39 40 struct netpoll *netpoll; 41 }; 42 43 void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 44 void netpoll_print_options(struct netpoll *np); 45 int netpoll_parse_options(struct netpoll *np, char *opt); 46 int __netpoll_setup(struct netpoll *np); 47 int netpoll_setup(struct netpoll *np); 48 int netpoll_trap(void); 49 void netpoll_set_trap(int trap); 50 void __netpoll_cleanup(struct netpoll *np); 51 void netpoll_cleanup(struct netpoll *np); 52 int __netpoll_rx(struct sk_buff *skb); 53 void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, 54 struct net_device *dev); netpoll_send_skb(struct netpoll * np,struct sk_buff * skb)55 static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 56 { 57 netpoll_send_skb_on_dev(np, skb, np->dev); 58 } 59 60 61 62 #ifdef CONFIG_NETPOLL netpoll_rx(struct sk_buff * skb)63 static inline bool netpoll_rx(struct sk_buff *skb) 64 { 65 struct netpoll_info *npinfo; 66 unsigned long flags; 67 bool ret = false; 68 69 local_irq_save(flags); 70 npinfo = rcu_dereference_bh(skb->dev->npinfo); 71 72 if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags)) 73 goto out; 74 75 spin_lock(&npinfo->rx_lock); 76 /* check rx_flags again with the lock held */ 77 if (npinfo->rx_flags && __netpoll_rx(skb)) 78 ret = true; 79 spin_unlock(&npinfo->rx_lock); 80 81 out: 82 local_irq_restore(flags); 83 return ret; 84 } 85 netpoll_rx_on(struct sk_buff * skb)86 static inline int netpoll_rx_on(struct sk_buff *skb) 87 { 88 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 89 90 return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags); 91 } 92 netpoll_receive_skb(struct sk_buff * skb)93 static inline int netpoll_receive_skb(struct sk_buff *skb) 94 { 95 if (!list_empty(&skb->dev->napi_list)) 96 return netpoll_rx(skb); 97 return 0; 98 } 99 netpoll_poll_lock(struct napi_struct * napi)100 static inline void *netpoll_poll_lock(struct napi_struct *napi) 101 { 102 struct net_device *dev = napi->dev; 103 104 if (dev && dev->npinfo) { 105 spin_lock(&napi->poll_lock); 106 napi->poll_owner = smp_processor_id(); 107 return napi; 108 } 109 return NULL; 110 } 111 netpoll_poll_unlock(void * have)112 static inline void netpoll_poll_unlock(void *have) 113 { 114 struct napi_struct *napi = have; 115 116 if (napi) { 117 napi->poll_owner = -1; 118 spin_unlock(&napi->poll_lock); 119 } 120 } 121 netpoll_tx_running(struct net_device * dev)122 static inline int netpoll_tx_running(struct net_device *dev) 123 { 124 return irqs_disabled(); 125 } 126 127 #else netpoll_rx(struct sk_buff * skb)128 static inline bool netpoll_rx(struct sk_buff *skb) 129 { 130 return 0; 131 } netpoll_rx_on(struct sk_buff * skb)132 static inline int netpoll_rx_on(struct sk_buff *skb) 133 { 134 return 0; 135 } netpoll_receive_skb(struct sk_buff * skb)136 static inline int netpoll_receive_skb(struct sk_buff *skb) 137 { 138 return 0; 139 } netpoll_poll_lock(struct napi_struct * napi)140 static inline void *netpoll_poll_lock(struct napi_struct *napi) 141 { 142 return NULL; 143 } netpoll_poll_unlock(void * have)144 static inline void netpoll_poll_unlock(void *have) 145 { 146 } netpoll_netdev_init(struct net_device * dev)147 static inline void netpoll_netdev_init(struct net_device *dev) 148 { 149 } netpoll_tx_running(struct net_device * dev)150 static inline int netpoll_tx_running(struct net_device *dev) 151 { 152 return 0; 153 } 154 #endif 155 156 #endif 157