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 unsigned long rx_flags; 43 spinlock_t rx_lock; 44 struct semaphore dev_lock; 45 struct list_head rx_np; /* netpolls that registered an rx_skb_hook */ 46 47 struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */ 48 struct sk_buff_head txq; 49 50 struct delayed_work tx_work; 51 52 struct netpoll *netpoll; 53 struct rcu_head rcu; 54 }; 55 56 #ifdef CONFIG_NETPOLL 57 extern void netpoll_rx_disable(struct net_device *dev); 58 extern void netpoll_rx_enable(struct net_device *dev); 59 #else 60 static inline void netpoll_rx_disable(struct net_device *dev) { return; } 61 static inline void netpoll_rx_enable(struct net_device *dev) { return; } 62 #endif 63 64 void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 65 void netpoll_print_options(struct netpoll *np); 66 int netpoll_parse_options(struct netpoll *np, char *opt); 67 int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp); 68 int netpoll_setup(struct netpoll *np); 69 int netpoll_trap(void); 70 void netpoll_set_trap(int trap); 71 void __netpoll_cleanup(struct netpoll *np); 72 void __netpoll_free_async(struct netpoll *np); 73 void netpoll_cleanup(struct netpoll *np); 74 int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo); 75 void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, 76 struct net_device *dev); 77 static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 78 { 79 unsigned long flags; 80 local_irq_save(flags); 81 netpoll_send_skb_on_dev(np, skb, np->dev); 82 local_irq_restore(flags); 83 } 84 85 #ifdef CONFIG_NETPOLL_TRAP 86 static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) 87 { 88 return !list_empty(&npinfo->rx_np); 89 } 90 #else 91 static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) 92 { 93 return false; 94 } 95 #endif 96 97 #ifdef CONFIG_NETPOLL 98 static inline bool netpoll_rx_on(struct sk_buff *skb) 99 { 100 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 101 102 return npinfo && (netpoll_rx_processing(npinfo) || npinfo->rx_flags); 103 } 104 105 static inline bool netpoll_rx(struct sk_buff *skb) 106 { 107 struct netpoll_info *npinfo; 108 unsigned long flags; 109 bool ret = false; 110 111 local_irq_save(flags); 112 113 if (!netpoll_rx_on(skb)) 114 goto out; 115 116 npinfo = rcu_dereference_bh(skb->dev->npinfo); 117 spin_lock(&npinfo->rx_lock); 118 /* check rx_processing again with the lock held */ 119 if (netpoll_rx_processing(npinfo) && __netpoll_rx(skb, npinfo)) 120 ret = true; 121 spin_unlock(&npinfo->rx_lock); 122 123 out: 124 local_irq_restore(flags); 125 return ret; 126 } 127 128 static inline int netpoll_receive_skb(struct sk_buff *skb) 129 { 130 if (!list_empty(&skb->dev->napi_list)) 131 return netpoll_rx(skb); 132 return 0; 133 } 134 135 static inline void *netpoll_poll_lock(struct napi_struct *napi) 136 { 137 struct net_device *dev = napi->dev; 138 139 if (dev && dev->npinfo) { 140 spin_lock(&napi->poll_lock); 141 napi->poll_owner = smp_processor_id(); 142 return napi; 143 } 144 return NULL; 145 } 146 147 static inline void netpoll_poll_unlock(void *have) 148 { 149 struct napi_struct *napi = have; 150 151 if (napi) { 152 napi->poll_owner = -1; 153 spin_unlock(&napi->poll_lock); 154 } 155 } 156 157 static inline bool netpoll_tx_running(struct net_device *dev) 158 { 159 return irqs_disabled(); 160 } 161 162 #else 163 static inline bool netpoll_rx(struct sk_buff *skb) 164 { 165 return false; 166 } 167 static inline bool netpoll_rx_on(struct sk_buff *skb) 168 { 169 return false; 170 } 171 static inline int netpoll_receive_skb(struct sk_buff *skb) 172 { 173 return 0; 174 } 175 static inline void *netpoll_poll_lock(struct napi_struct *napi) 176 { 177 return NULL; 178 } 179 static inline void netpoll_poll_unlock(void *have) 180 { 181 } 182 static inline void netpoll_netdev_init(struct net_device *dev) 183 { 184 } 185 static inline bool netpoll_tx_running(struct net_device *dev) 186 { 187 return false; 188 } 189 #endif 190 191 #endif 192