include/linux/netpoll.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Common code for low-level network console, dump, and debugger code
   4  *
   5  * Derived from netconsole, kgdb-over-ethernet, and netdump patches
   6  */
   7
   8 #ifndef _LINUX_NETPOLL_H
   9 #define _LINUX_NETPOLL_H
  10
  11 #include <linux/netdevice.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/rcupdate.h>
  14 #include <linux/list.h>
  15 #include <linux/refcount.h>
  16
  17 union inet_addr {
  18         __u32           all[4];
  19         __be32          ip;
  20         __be32          ip6[4];
  21         struct in_addr  in;
  22         struct in6_addr in6;
  23 };
  24
  25 struct netpoll {
  26         struct net_device *dev;
  27         char dev_name[IFNAMSIZ];
  28         const char *name;
  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 work_struct cleanup_work;
  36 };
  37
  38 struct netpoll_info {
  39         refcount_t refcnt;
  40
  41         struct semaphore dev_lock;
  42
  43         struct sk_buff_head txq;
  44
  45         struct delayed_work tx_work;
  46
  47         struct netpoll *netpoll;
  48         struct rcu_head rcu;
  49 };
  50
  51 #ifdef CONFIG_NETPOLL
  52 void netpoll_poll_dev(struct net_device *dev);
  53 void netpoll_poll_disable(struct net_device *dev);
  54 void netpoll_poll_enable(struct net_device *dev);
  55 #else
  56 static inline void netpoll_poll_disable(struct net_device *dev) { return; }
  57 static inline void netpoll_poll_enable(struct net_device *dev) { return; }
  58 #endif
  59
  60 void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
  61 void netpoll_print_options(struct netpoll *np);
  62 int netpoll_parse_options(struct netpoll *np, char *opt);
  63 int __netpoll_setup(struct netpoll *np, struct net_device *ndev);
  64 int netpoll_setup(struct netpoll *np);
  65 void __netpoll_cleanup(struct netpoll *np);
  66 void __netpoll_free_async(struct netpoll *np);
  67 void netpoll_cleanup(struct netpoll *np);
  68 void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
  69                              struct net_device *dev);
  70 static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
  71 {
  72         unsigned long flags;
  73         local_irq_save(flags);
  74         netpoll_send_skb_on_dev(np, skb, np->dev);
  75         local_irq_restore(flags);
  76 }
  77
  78 #ifdef CONFIG_NETPOLL
  79 static inline void *netpoll_poll_lock(struct napi_struct *napi)
  80 {
  81         struct net_device *dev = napi->dev;
  82
  83         if (dev && dev->npinfo) {
  84                 int owner = smp_processor_id();
  85
  86                 while (cmpxchg(&napi->poll_owner, -1, owner) != -1)
  87                         cpu_relax();
  88
  89                 return napi;
  90         }
  91         return NULL;
  92 }
  93
  94 static inline void netpoll_poll_unlock(void *have)
  95 {
  96         struct napi_struct *napi = have;
  97
  98         if (napi)
  99                 smp_store_release(&napi->poll_owner, -1);
 100 }
 101
 102 static inline bool netpoll_tx_running(struct net_device *dev)
 103 {
 104         return irqs_disabled();
 105 }
 106
 107 #else
 108 static inline void *netpoll_poll_lock(struct napi_struct *napi)
 109 {
 110         return NULL;
 111 }
 112 static inline void netpoll_poll_unlock(void *have)
 113 {
 114 }
 115 static inline void netpoll_netdev_init(struct net_device *dev)
 116 {
 117 }
 118 static inline bool netpoll_tx_running(struct net_device *dev)
 119 {
 120         return false;
 121 }
 122 #endif
 123
 124 #endif