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 void __netpoll_cleanup(struct netpoll *np); 69 void __netpoll_free_async(struct netpoll *np); 70 void netpoll_cleanup(struct netpoll *np); 71 int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo); 72 void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, 73 struct net_device *dev); 74 static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 75 { 76 unsigned long flags; 77 local_irq_save(flags); 78 netpoll_send_skb_on_dev(np, skb, np->dev); 79 local_irq_restore(flags); 80 } 81 82 #ifdef CONFIG_NETPOLL_TRAP 83 int netpoll_trap(void); 84 void netpoll_set_trap(int 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 int netpoll_trap(void) 91 { 92 return 0; 93 } 94 static inline void netpoll_set_trap(int trap) 95 { 96 } 97 static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) 98 { 99 return false; 100 } 101 #endif 102 103 #ifdef CONFIG_NETPOLL 104 static inline bool netpoll_rx_on(struct sk_buff *skb) 105 { 106 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 107 108 return npinfo && netpoll_rx_processing(npinfo); 109 } 110 111 static inline bool netpoll_rx(struct sk_buff *skb) 112 { 113 struct netpoll_info *npinfo; 114 unsigned long flags; 115 bool ret = false; 116 117 local_irq_save(flags); 118 119 if (!netpoll_rx_on(skb)) 120 goto out; 121 122 npinfo = rcu_dereference_bh(skb->dev->npinfo); 123 spin_lock(&npinfo->rx_lock); 124 /* check rx_processing again with the lock held */ 125 if (netpoll_rx_processing(npinfo) && __netpoll_rx(skb, npinfo)) 126 ret = true; 127 spin_unlock(&npinfo->rx_lock); 128 129 out: 130 local_irq_restore(flags); 131 return ret; 132 } 133 134 static inline int netpoll_receive_skb(struct sk_buff *skb) 135 { 136 if (!list_empty(&skb->dev->napi_list)) 137 return netpoll_rx(skb); 138 return 0; 139 } 140 141 static inline void *netpoll_poll_lock(struct napi_struct *napi) 142 { 143 struct net_device *dev = napi->dev; 144 145 if (dev && dev->npinfo) { 146 spin_lock(&napi->poll_lock); 147 napi->poll_owner = smp_processor_id(); 148 return napi; 149 } 150 return NULL; 151 } 152 153 static inline void netpoll_poll_unlock(void *have) 154 { 155 struct napi_struct *napi = have; 156 157 if (napi) { 158 napi->poll_owner = -1; 159 spin_unlock(&napi->poll_lock); 160 } 161 } 162 163 static inline bool netpoll_tx_running(struct net_device *dev) 164 { 165 return irqs_disabled(); 166 } 167 168 #else 169 static inline bool netpoll_rx(struct sk_buff *skb) 170 { 171 return false; 172 } 173 static inline bool netpoll_rx_on(struct sk_buff *skb) 174 { 175 return false; 176 } 177 static inline int netpoll_receive_skb(struct sk_buff *skb) 178 { 179 return 0; 180 } 181 static inline void *netpoll_poll_lock(struct napi_struct *napi) 182 { 183 return NULL; 184 } 185 static inline void netpoll_poll_unlock(void *have) 186 { 187 } 188 static inline void netpoll_netdev_init(struct net_device *dev) 189 { 190 } 191 static inline bool netpoll_tx_running(struct net_device *dev) 192 { 193 return false; 194 } 195 #endif 196 197 #endif 198