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_skb_hook)(struct netpoll *np, int source, struct sk_buff *skb, 28 int offset, int len); 29 30 union inet_addr local_ip, remote_ip; 31 bool ipv6; 32 u16 local_port, remote_port; 33 u8 remote_mac[ETH_ALEN]; 34 35 struct list_head rx; /* rx_np list element */ 36 struct work_struct cleanup_work; 37 }; 38 39 struct netpoll_info { 40 atomic_t refcnt; 41 42 spinlock_t rx_lock; 43 struct semaphore dev_lock; 44 struct list_head rx_np; /* netpolls that registered an rx_skb_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 #ifdef CONFIG_NETPOLL_TRAP 85 static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) 86 { 87 return !list_empty(&npinfo->rx_np); 88 } 89 #else 90 static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) 91 { 92 return false; 93 } 94 #endif 95 96 #ifdef CONFIG_NETPOLL 97 static inline bool netpoll_rx_on(struct sk_buff *skb) 98 { 99 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 100 101 return npinfo && netpoll_rx_processing(npinfo); 102 } 103 104 static inline bool netpoll_rx(struct sk_buff *skb) 105 { 106 struct netpoll_info *npinfo; 107 unsigned long flags; 108 bool ret = false; 109 110 local_irq_save(flags); 111 112 if (!netpoll_rx_on(skb)) 113 goto out; 114 115 npinfo = rcu_dereference_bh(skb->dev->npinfo); 116 spin_lock(&npinfo->rx_lock); 117 /* check rx_processing again with the lock held */ 118 if (netpoll_rx_processing(npinfo) && __netpoll_rx(skb, npinfo)) 119 ret = true; 120 spin_unlock(&npinfo->rx_lock); 121 122 out: 123 local_irq_restore(flags); 124 return ret; 125 } 126 127 static inline int netpoll_receive_skb(struct sk_buff *skb) 128 { 129 if (!list_empty(&skb->dev->napi_list)) 130 return netpoll_rx(skb); 131 return 0; 132 } 133 134 static inline void *netpoll_poll_lock(struct napi_struct *napi) 135 { 136 struct net_device *dev = napi->dev; 137 138 if (dev && dev->npinfo) { 139 spin_lock(&napi->poll_lock); 140 napi->poll_owner = smp_processor_id(); 141 return napi; 142 } 143 return NULL; 144 } 145 146 static inline void netpoll_poll_unlock(void *have) 147 { 148 struct napi_struct *napi = have; 149 150 if (napi) { 151 napi->poll_owner = -1; 152 spin_unlock(&napi->poll_lock); 153 } 154 } 155 156 static inline bool netpoll_tx_running(struct net_device *dev) 157 { 158 return irqs_disabled(); 159 } 160 161 #else 162 static inline bool netpoll_rx(struct sk_buff *skb) 163 { 164 return false; 165 } 166 static inline bool netpoll_rx_on(struct sk_buff *skb) 167 { 168 return false; 169 } 170 static inline int netpoll_receive_skb(struct sk_buff *skb) 171 { 172 return 0; 173 } 174 static inline void *netpoll_poll_lock(struct napi_struct *napi) 175 { 176 return NULL; 177 } 178 static inline void netpoll_poll_unlock(void *have) 179 { 180 } 181 static inline void netpoll_netdev_init(struct net_device *dev) 182 { 183 } 184 static inline bool netpoll_tx_running(struct net_device *dev) 185 { 186 return false; 187 } 188 #endif 189 190 #endif 191