/* SPDX-License-Identifier: GPL-2.0 */

  /*
   * Common code for low-level network console, dump, and debugger code
   *
   * Derived from netconsole, kgdb-over-ethernet, and netdump patches
   */
  
  #ifndef _LINUX_NETPOLL_H
  #define _LINUX_NETPOLL_H
  
  #include <linux/netdevice.h>
  #include <linux/interrupt.h>

  #include <linux/rcupdate.h>

  #include <linux/list.h>

  #include <linux/refcount.h>

  union inet_addr {
  	__u32		all[4];
  	__be32		ip;
  	__be32		ip6[4];
  	struct in_addr	in;
  	struct in6_addr	in6;
  };

  struct netpoll {
  	struct net_device *dev;

  	char dev_name[IFNAMSIZ];
  	const char *name;

  	union inet_addr local_ip, remote_ip;
  	bool ipv6;

  	u16 local_port, remote_port;

  	u8 remote_mac[ETH_ALEN];

  	struct work_struct cleanup_work;

  };
  
  struct netpoll_info {

  	refcount_t refcnt;

  	struct semaphore dev_lock;

  	struct sk_buff_head txq;

  	struct delayed_work tx_work;

  
  	struct netpoll *netpoll;

  	struct rcu_head rcu;

  };

  #ifdef CONFIG_NETPOLL

  extern void netpoll_poll_disable(struct net_device *dev);
  extern void netpoll_poll_enable(struct net_device *dev);

  #else

  static inline void netpoll_poll_disable(struct net_device *dev) { return; }
  static inline void netpoll_poll_enable(struct net_device *dev) { return; }

  #endif

  void netpoll_send_udp(struct netpoll *np, const char *msg, int len);

  void netpoll_print_options(struct netpoll *np);

  int netpoll_parse_options(struct netpoll *np, char *opt);

  int __netpoll_setup(struct netpoll *np, struct net_device *ndev);

  int netpoll_setup(struct netpoll *np);

  void __netpoll_cleanup(struct netpoll *np);

  void __netpoll_free_async(struct netpoll *np);

  void netpoll_cleanup(struct netpoll *np);

  void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
  			     struct net_device *dev);
  static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
  {

  	unsigned long flags;
  	local_irq_save(flags);

  	netpoll_send_skb_on_dev(np, skb, np->dev);

  	local_irq_restore(flags);

  }

  #ifdef CONFIG_NETPOLL

  static inline void *netpoll_poll_lock(struct napi_struct *napi)
  {
  	struct net_device *dev = napi->dev;

  	if (dev && dev->npinfo) {

  		int owner = smp_processor_id();
  
  		while (cmpxchg(&napi->poll_owner, -1, owner) != -1)
  			cpu_relax();

  		return napi;

  	}

  	return NULL;

  }

  static inline void netpoll_poll_unlock(void *have)

  {

  	struct napi_struct *napi = have;

  	if (napi)
  		smp_store_release(&napi->poll_owner, -1);

  }

  static inline bool netpoll_tx_running(struct net_device *dev)

  {
  	return irqs_disabled();
  }

  #else

  static inline void *netpoll_poll_lock(struct napi_struct *napi)
  {
  	return NULL;
  }
  static inline void netpoll_poll_unlock(void *have)
  {
  }
  static inline void netpoll_netdev_init(struct net_device *dev)
  {
  }

  static inline bool netpoll_tx_running(struct net_device *dev)

  {

  	return false;

  }

  #endif
  
  #endif