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 86 87 #ifdef CONFIG_NETPOLL 88 static inline bool netpoll_rx_on(struct sk_buff *skb) 89 { 90 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 91 92 return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags); 93 } 94 95 static inline bool netpoll_rx(struct sk_buff *skb) 96 { 97 struct netpoll_info *npinfo; 98 unsigned long flags; 99 bool ret = false; 100 101 local_irq_save(flags); 102 103 if (!netpoll_rx_on(skb)) 104 goto out; 105 106 npinfo = rcu_dereference_bh(skb->dev->npinfo); 107 spin_lock(&npinfo->rx_lock); 108 /* check rx_flags again with the lock held */ 109 if (npinfo->rx_flags && __netpoll_rx(skb, npinfo)) 110 ret = true; 111 spin_unlock(&npinfo->rx_lock); 112 113 out: 114 local_irq_restore(flags); 115 return ret; 116 } 117 118 static inline int netpoll_receive_skb(struct sk_buff *skb) 119 { 120 if (!list_empty(&skb->dev->napi_list)) 121 return netpoll_rx(skb); 122 return 0; 123 } 124 125 static inline void *netpoll_poll_lock(struct napi_struct *napi) 126 { 127 struct net_device *dev = napi->dev; 128 129 if (dev && dev->npinfo) { 130 spin_lock(&napi->poll_lock); 131 napi->poll_owner = smp_processor_id(); 132 return napi; 133 } 134 return NULL; 135 } 136 137 static inline void netpoll_poll_unlock(void *have) 138 { 139 struct napi_struct *napi = have; 140 141 if (napi) { 142 napi->poll_owner = -1; 143 spin_unlock(&napi->poll_lock); 144 } 145 } 146 147 static inline bool netpoll_tx_running(struct net_device *dev) 148 { 149 return irqs_disabled(); 150 } 151 152 #else 153 static inline bool netpoll_rx(struct sk_buff *skb) 154 { 155 return false; 156 } 157 static inline bool netpoll_rx_on(struct sk_buff *skb) 158 { 159 return false; 160 } 161 static inline int netpoll_receive_skb(struct sk_buff *skb) 162 { 163 return 0; 164 } 165 static inline void *netpoll_poll_lock(struct napi_struct *napi) 166 { 167 return NULL; 168 } 169 static inline void netpoll_poll_unlock(void *have) 170 { 171 } 172 static inline void netpoll_netdev_init(struct net_device *dev) 173 { 174 } 175 static inline bool netpoll_tx_running(struct net_device *dev) 176 { 177 return false; 178 } 179 #endif 180 181 #endif 182