LXR linux/include/linux/netpoll.h

   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        char dev_name[IFNAMSIZ];
  18        const char *name;
  19        void (*rx_hook)(struct netpoll *, int, char *, int);
  20
  21        __be32 local_ip, remote_ip;
  22        u16 local_port, remote_port;
  23        u8 remote_mac[ETH_ALEN];
  24
  25        struct list_head rx; /* rx_np list element */
  26};
  27
  28struct netpoll_info {
  29        atomic_t refcnt;
  30
  31        int rx_flags;
  32        spinlock_t rx_lock;
  33        struct list_head rx_np; /* netpolls that registered an rx_hook */
  34
  35        struct sk_buff_head arp_tx; /* list of arp requests to reply to */
  36        struct sk_buff_head txq;
  37
  38        struct delayed_work tx_work;
  39
  40        struct netpoll *netpoll;
  41};
  42
  43void netpoll_poll_dev(struct net_device *dev);
  44void netpoll_poll(struct netpoll *np);
  45void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
  46void netpoll_print_options(struct netpoll *np);
  47int netpoll_parse_options(struct netpoll *np, char *opt);
  48int __netpoll_setup(struct netpoll *np);
  49int netpoll_setup(struct netpoll *np);
  50int netpoll_trap(void);
  51void netpoll_set_trap(int trap);
  52void __netpoll_cleanup(struct netpoll *np);
  53void netpoll_cleanup(struct netpoll *np);
  54int __netpoll_rx(struct sk_buff *skb);
  55void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
  56                             struct net_device *dev);
  57static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
  58{
  59        netpoll_send_skb_on_dev(np, skb, np->dev);
  60}
  61
  62
  63
  64#ifdef CONFIG_NETPOLL
  65static inline bool netpoll_rx(struct sk_buff *skb)
  66{
  67        struct netpoll_info *npinfo;
  68        unsigned long flags;
  69        bool ret = false;
  70
  71        local_irq_save(flags);
  72        npinfo = rcu_dereference_bh(skb->dev->npinfo);
  73
  74        if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags))
  75                goto out;
  76
  77        spin_lock(&npinfo->rx_lock);
  78        /* check rx_flags again with the lock held */
  79        if (npinfo->rx_flags && __netpoll_rx(skb))
  80                ret = true;
  81        spin_unlock(&npinfo->rx_lock);
  82
  83out:
  84        local_irq_restore(flags);
  85        return ret;
  86}
  87
  88static inline int 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
  95static inline int netpoll_receive_skb(struct sk_buff *skb)
  96{
  97        if (!list_empty(&skb->dev->napi_list))
  98                return netpoll_rx(skb);
  99        return 0;
 100}
 101
 102static inline void *netpoll_poll_lock(struct napi_struct *napi)
 103{
 104        struct net_device *dev = napi->dev;
 105
 106        if (dev && dev->npinfo) {
 107                spin_lock(&napi->poll_lock);
 108                napi->poll_owner = smp_processor_id();
 109                return napi;
 110        }
 111        return NULL;
 112}
 113
 114static inline void netpoll_poll_unlock(void *have)
 115{
 116        struct napi_struct *napi = have;
 117
 118        if (napi) {
 119                napi->poll_owner = -1;
 120                spin_unlock(&napi->poll_lock);
 121        }
 122}
 123
 124static inline int netpoll_tx_running(struct net_device *dev)
 125{
 126        return irqs_disabled();
 127}
 128
 129#else
 130static inline bool netpoll_rx(struct sk_buff *skb)
 131{
 132        return 0;
 133}
 134static inline int netpoll_rx_on(struct sk_buff *skb)
 135{
 136        return 0;
 137}
 138static inline int netpoll_receive_skb(struct sk_buff *skb)
 139{
 140        return 0;
 141}
 142static inline void *netpoll_poll_lock(struct napi_struct *napi)
 143{
 144        return NULL;
 145}
 146static inline void netpoll_poll_unlock(void *have)
 147{
 148}
 149static inline void netpoll_netdev_init(struct net_device *dev)
 150{
 151}
 152static inline int netpoll_tx_running(struct net_device *dev)
 153{
 154        return 0;
 155}
 156#endif
 157
 158#endif
 159