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 15struct netpoll { 16 struct net_device *dev; 17 struct net_device *real_dev; 18 char dev_name[IFNAMSIZ]; 19 const char *name; 20 void (*rx_hook)(struct netpoll *, int, char *, int); 21 22 __be32 local_ip, remote_ip; 23 u16 local_port, remote_port; 24 u8 remote_mac[ETH_ALEN]; 25 26 struct list_head rx; /* rx_np list element */ 27}; 28 29struct netpoll_info { 30 atomic_t refcnt; 31 32 int rx_flags; 33 spinlock_t rx_lock; 34 struct list_head rx_np; /* netpolls that registered an rx_hook */ 35 36 struct sk_buff_head arp_tx; /* list of arp requests to reply to */ 37 struct sk_buff_head txq; 38 39 struct delayed_work tx_work; 40 41 struct netpoll *netpoll; 42}; 43 44void netpoll_poll_dev(struct net_device *dev); 45void netpoll_poll(struct netpoll *np); 46void netpoll_send_udp(struct netpoll *np, const char *msg, int len); 47void netpoll_print_options(struct netpoll *np); 48int netpoll_parse_options(struct netpoll *np, char *opt); 49int __netpoll_setup(struct netpoll *np); 50int netpoll_setup(struct netpoll *np); 51int netpoll_trap(void); 52void netpoll_set_trap(int trap); 53void __netpoll_cleanup(struct netpoll *np); 54void netpoll_cleanup(struct netpoll *np); 55int __netpoll_rx(struct sk_buff *skb); 56void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb); 57 58 59#ifdef CONFIG_NETPOLL 60static inline bool netpoll_rx(struct sk_buff *skb) 61{ 62 struct netpoll_info *npinfo; 63 unsigned long flags; 64 bool ret = false; 65 66 local_irq_save(flags); 67 npinfo = rcu_dereference_bh(skb->dev->npinfo); 68 69 if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags)) 70 goto out; 71 72 spin_lock(&npinfo->rx_lock); 73 /* check rx_flags again with the lock held */ 74 if (npinfo->rx_flags && __netpoll_rx(skb)) 75 ret = true; 76 spin_unlock(&npinfo->rx_lock); 77 78out: 79 local_irq_restore(flags); 80 return ret; 81} 82 83static inline int netpoll_rx_on(struct sk_buff *skb) 84{ 85 struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); 86 87 return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags); 88} 89 90static inline int netpoll_receive_skb(struct sk_buff *skb) 91{ 92 if (!list_empty(&skb->dev->napi_list)) 93 return netpoll_rx(skb); 94 return 0; 95} 96 97static inline void *netpoll_poll_lock(struct napi_struct *napi) 98{ 99 struct net_device *dev = napi->dev; 100 101 if (dev && dev->npinfo) { 102 spin_lock(&napi->poll_lock); 103 napi->poll_owner = smp_processor_id(); 104 return napi; 105 } 106 return NULL; 107} 108 109static inline void netpoll_poll_unlock(void *have) 110{ 111 struct napi_struct *napi = have; 112 113 if (napi) { 114 napi->poll_owner = -1; 115 spin_unlock(&napi->poll_lock); 116 } 117} 118 119static inline int netpoll_tx_running(struct net_device *dev) 120{ 121 return irqs_disabled(); 122} 123 124#else 125static inline bool netpoll_rx(struct sk_buff *skb) 126{ 127 return 0; 128} 129static inline int netpoll_rx_on(struct sk_buff *skb) 130{ 131 return 0; 132} 133static inline int netpoll_receive_skb(struct sk_buff *skb) 134{ 135 return 0; 136} 137static inline void *netpoll_poll_lock(struct napi_struct *napi) 138{ 139 return NULL; 140} 141static inline void netpoll_poll_unlock(void *have) 142{ 143} 144static inline void netpoll_netdev_init(struct net_device *dev) 145{ 146} 147static inline int netpoll_tx_running(struct net_device *dev) 148{ 149 return 0; 150} 151#endif 152 153#endif 154