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 union inet_addr { 16 __u32 all[4]; 17 __be32 ip; 18 __be32 ip6[4]; 19 struct in_addr in; 20 struct in6_addr in6; 21 }; 22 23 struct netpoll { 24 struct net_device *dev; 25 char dev_name[IFNAMSIZ]; 26 const char *name; 27 void (*rx_hook)(struct netpoll *, int, char *, int); 28 29 union inet_addr local_ip, remote_ip; 30 bool ipv6; 31 u16 local_port, remote_port; 32 u8 remote_mac[ETH_ALEN]; 33 34 struct list_head rx; /* rx_np list element */ 35 struct work_struct cleanup_work; 36 }; 37 38 struct netpoll_info { 39 atomic_t refcnt; 40 41 unsigned long rx_flags; 42 spinlock_t rx_lock; 43 struct semaphore dev_lock; 44 struct list_head rx_np; /* netpolls that registered an rx_hook */ 45 46 struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */ 47 struct sk_buff_head txq; 48 49 struct delayed_work tx_work; 50 51 struct netpoll *netpoll; 52 struct rcu_head rcu; 53 }; 54 55 #ifdef CONFIG_NETPOLL 56 extern void netpoll_rx_disable(struct net_device *dev); 57 extern void netpoll_rx_enable(struct net_device *dev); 58 #else 59 static inline void netpoll_rx_disable(struct net_device *dev) { return; } 60 static inline void netpoll_rx_enable(struct net_device *dev) { return; } 61 #endif 62 63 void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 64 void netpoll_print_options(struct netpoll *np); 65 int netpoll_parse_options(struct netpoll *np, char *opt); 66 int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp); 67 int netpoll_setup(struct netpoll *np); 68 int netpoll_trap(void); 69 void netpoll_set_trap(int trap); 70 void __netpoll_cleanup(struct netpoll *np); 71 void __netpoll_free_async(struct netpoll *np); 72 void netpoll_cleanup(struct netpoll *np); 73 int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo); 74 void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, 75 struct net_device *dev); 76 static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 77 { 78 unsigned long flags; 79 local_irq_save(flags); 80 netpoll_send_skb_on_dev(np, skb, np->dev); 81 local_irq_restore(flags); 82 } 83 84 85 86 #ifdef CONFIG_NETPOLL 87 static inline bool netpoll_rx_on(struct sk_buff *skb) 88 { 89 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 90 91 return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags); 92 } 93 94 static inline bool netpoll_rx(struct sk_buff *skb) 95 { 96 struct netpoll_info *npinfo; 97 unsigned long flags; 98 bool ret = false; 99 100 local_irq_save(flags); 101 102 if (!netpoll_rx_on(skb)) 103 goto out; 104 105 npinfo = rcu_dereference_bh(skb->dev->npinfo); 106 spin_lock(&npinfo->rx_lock); 107 /* check rx_flags again with the lock held */ 108 if (npinfo->rx_flags && __netpoll_rx(skb, npinfo)) 109 ret = true; 110 spin_unlock(&npinfo->rx_lock); 111 112 out: 113 local_irq_restore(flags); 114 return ret; 115 } 116 117 static inline int netpoll_receive_skb(struct sk_buff *skb) 118 { 119 if (!list_empty(&skb->dev->napi_list)) 120 return netpoll_rx(skb); 121 return 0; 122 } 123 124 static inline void *netpoll_poll_lock(struct napi_struct *napi) 125 { 126 struct net_device *dev = napi->dev; 127 128 if (dev && dev->npinfo) { 129 spin_lock(&napi->poll_lock); 130 napi->poll_owner = smp_processor_id(); 131 return napi; 132 } 133 return NULL; 134 } 135 136 static inline void netpoll_poll_unlock(void *have) 137 { 138 struct napi_struct *napi = have; 139 140 if (napi) { 141 napi->poll_owner = -1; 142 spin_unlock(&napi->poll_lock); 143 } 144 } 145 146 static inline bool netpoll_tx_running(struct net_device *dev) 147 { 148 return irqs_disabled(); 149 } 150 151 #else 152 static inline bool netpoll_rx(struct sk_buff *skb) 153 { 154 return false; 155 } 156 static inline bool netpoll_rx_on(struct sk_buff *skb) 157 { 158 return false; 159 } 160 static inline int netpoll_receive_skb(struct sk_buff *skb) 161 { 162 return 0; 163 } 164 static inline void *netpoll_poll_lock(struct napi_struct *napi) 165 { 166 return NULL; 167 } 168 static inline void netpoll_poll_unlock(void *have) 169 { 170 } 171 static inline void netpoll_netdev_init(struct net_device *dev) 172 { 173 } 174 static inline bool netpoll_tx_running(struct net_device *dev) 175 { 176 return false; 177 } 178 #endif 179 180 #endif 181