include/net/inet_timewait_sock.h - maze/linux - Git at Google

 /*
  * INET		An implementation of the TCP/IP protocol suite for the LINUX
  *		operating system.  INET is implemented using the  BSD Socket
  *		interface as the means of communication with the user level.
  *
  *		Definitions for a generic INET TIMEWAIT sock
  *
  *		From code originally in net/tcp.h
  *
  *		This program is free software; you can redistribute it and/or
  *		modify it under the terms of the GNU General Public License
  *		as published by the Free Software Foundation; either version
  *		2 of the License, or (at your option) any later version.
  */
 #ifndef _INET_TIMEWAIT_SOCK_
 #define _INET_TIMEWAIT_SOCK_


 #include <linux/kmemcheck.h>
 #include <linux/list.h>
 #include <linux/module.h>
 #include <linux/timer.h>
 #include <linux/types.h>
 #include <linux/workqueue.h>

 #include <net/inet_sock.h>
 #include <net/sock.h>
 #include <net/tcp_states.h>
 #include <net/timewait_sock.h>

 #include <asm/atomic.h>

 struct inet_hashinfo;

 #define INET_TWDR_RECYCLE_SLOTS_LOG	5
 #define INET_TWDR_RECYCLE_SLOTS		(1 << INET_TWDR_RECYCLE_SLOTS_LOG)

 /*
  * If time > 4sec, it is "slow" path, no recycling is required,
  * so that we select tick to get range about 4 seconds.
  */
 #if HZ <= 16 || HZ > 4096
 # error Unsupported: HZ <= 16 or HZ > 4096
 #elif HZ <= 32
 # define INET_TWDR_RECYCLE_TICK (5 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #elif HZ <= 64
 # define INET_TWDR_RECYCLE_TICK (6 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #elif HZ <= 128
 # define INET_TWDR_RECYCLE_TICK (7 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #elif HZ <= 256
 # define INET_TWDR_RECYCLE_TICK (8 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #elif HZ <= 512
 # define INET_TWDR_RECYCLE_TICK (9 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #elif HZ <= 1024
 # define INET_TWDR_RECYCLE_TICK (10 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #elif HZ <= 2048
 # define INET_TWDR_RECYCLE_TICK (11 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #else
 # define INET_TWDR_RECYCLE_TICK (12 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
 #endif

 /* TIME_WAIT reaping mechanism. */
 #define INET_TWDR_TWKILL_SLOTS	8 /* Please keep this a power of 2. */

 #define INET_TWDR_TWKILL_QUOTA 100

 struct inet_timewait_death_row {
 	/* Short-time timewait calendar */
 	int			twcal_hand;
 	unsigned long		twcal_jiffie;
 	struct timer_list	twcal_timer;
 	struct hlist_head	twcal_row[INET_TWDR_RECYCLE_SLOTS];

 	spinlock_t		death_lock;
 	int			tw_count;
 	int			period;
 	u32			thread_slots;
 	struct work_struct	twkill_work;
 	struct timer_list	tw_timer;
 	int			slot;
 	struct hlist_head	cells[INET_TWDR_TWKILL_SLOTS];
 	struct inet_hashinfo 	*hashinfo;
 	int			sysctl_tw_recycle;
 	int			sysctl_max_tw_buckets;
 };

 extern void inet_twdr_hangman(unsigned long data);
 extern void inet_twdr_twkill_work(struct work_struct *work);
 extern void inet_twdr_twcal_tick(unsigned long data);

 #if (BITS_PER_LONG == 64)
 #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 8
 #else
 #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 4
 #endif

 struct inet_bind_bucket;

 /*
  * This is a TIME_WAIT sock. It works around the memory consumption
  * problems of sockets in such a state on heavily loaded servers, but
  * without violating the protocol specification.
  */
 struct inet_timewait_sock {
 	/*
 	 * Now struct sock also uses sock_common, so please just
 	 * don't add nothing before this first member (__tw_common) --acme
 	 */
 	struct sock_common	__tw_common;
 #define tw_family		__tw_common.skc_family
 #define tw_state		__tw_common.skc_state
 #define tw_reuse		__tw_common.skc_reuse
 #define tw_bound_dev_if		__tw_common.skc_bound_dev_if
 #define tw_node			__tw_common.skc_nulls_node
 #define tw_bind_node		__tw_common.skc_bind_node
 #define tw_refcnt		__tw_common.skc_refcnt
 #define tw_hash			__tw_common.skc_hash
 #define tw_prot			__tw_common.skc_prot
 #define tw_net			__tw_common.skc_net
 	int			tw_timeout;
 	volatile unsigned char	tw_substate;
 	/* 3 bits hole, try to pack */
 	unsigned char		tw_rcv_wscale;
 	/* Socket demultiplex comparisons on incoming packets. */
 	/* these five are in inet_sock */
 	__be16			tw_sport;
 	__be32			tw_daddr __attribute__((aligned(INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES)));
 	__be32			tw_rcv_saddr;
 	__be16			tw_dport;
 	__u16			tw_num;
 	kmemcheck_bitfield_begin(flags);
 	/* And these are ours. */
 	unsigned int		tw_ipv6only     : 1,
 				tw_transparent  : 1,
 				tw_pad		: 14,	/* 14 bits hole */
 				tw_ipv6_offset  : 16;
 	kmemcheck_bitfield_end(flags);
 	unsigned long		tw_ttd;
 	struct inet_bind_bucket	*tw_tb;
 	struct hlist_node	tw_death_node;
 };

 static inline void inet_twsk_add_node_rcu(struct inet_timewait_sock *tw,
 				      struct hlist_nulls_head *list)
 {
 	hlist_nulls_add_head_rcu(&tw->tw_node, list);
 }

 static inline void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
 					   struct hlist_head *list)
 {
 	hlist_add_head(&tw->tw_bind_node, list);
 }

 static inline int inet_twsk_dead_hashed(const struct inet_timewait_sock *tw)
 {
 	return !hlist_unhashed(&tw->tw_death_node);
 }

 static inline void inet_twsk_dead_node_init(struct inet_timewait_sock *tw)
 {
 	tw->tw_death_node.pprev = NULL;
 }

 static inline void __inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
 {
 	__hlist_del(&tw->tw_death_node);
 	inet_twsk_dead_node_init(tw);
 }

 static inline int inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
 {
 	if (inet_twsk_dead_hashed(tw)) {
 		__inet_twsk_del_dead_node(tw);
 		return 1;
 	}
 	return 0;
 }

 #define inet_twsk_for_each(tw, node, head) \
 	hlist_nulls_for_each_entry(tw, node, head, tw_node)

 #define inet_twsk_for_each_inmate(tw, node, jail) \
 	hlist_for_each_entry(tw, node, jail, tw_death_node)

 #define inet_twsk_for_each_inmate_safe(tw, node, safe, jail) \
 	hlist_for_each_entry_safe(tw, node, safe, jail, tw_death_node)

 static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
 {
 	return (struct inet_timewait_sock *)sk;
 }

 static inline __be32 inet_rcv_saddr(const struct sock *sk)
 {
 	return likely(sk->sk_state != TCP_TIME_WAIT) ?
 		inet_sk(sk)->rcv_saddr : inet_twsk(sk)->tw_rcv_saddr;
 }

 extern void inet_twsk_put(struct inet_timewait_sock *tw);

 extern struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
 						  const int state);

 extern void __inet_twsk_hashdance(struct inet_timewait_sock *tw,
 				  struct sock *sk,
 				  struct inet_hashinfo *hashinfo);

 extern void inet_twsk_schedule(struct inet_timewait_sock *tw,
 			       struct inet_timewait_death_row *twdr,
 			       const int timeo, const int timewait_len);
 extern void inet_twsk_deschedule(struct inet_timewait_sock *tw,
 				 struct inet_timewait_death_row *twdr);

 extern void inet_twsk_purge(struct net *net, struct inet_hashinfo *hashinfo,
 			    struct inet_timewait_death_row *twdr, int family);

 static inline
 struct net *twsk_net(const struct inet_timewait_sock *twsk)
 {
 #ifdef CONFIG_NET_NS
 	return twsk->tw_net;
 #else
 	return &init_net;
 #endif
 }

 static inline
 void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
 {
 #ifdef CONFIG_NET_NS
 	twsk->tw_net = net;
 #endif
 }
 #endif	/* _INET_TIMEWAIT_SOCK_ */
	/*
	* INET An implementation of the TCP/IP protocol suite for the LINUX
	* operating system. INET is implemented using the BSD Socket
	* interface as the means of communication with the user level.
	*
	* Definitions for a generic INET TIMEWAIT sock
	*
	* From code originally in net/tcp.h
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*/
	#ifndef _INET_TIMEWAIT_SOCK_
	#define _INET_TIMEWAIT_SOCK_


	#include <linux/kmemcheck.h>
	#include <linux/list.h>
	#include <linux/module.h>
	#include <linux/timer.h>
	#include <linux/types.h>
	#include <linux/workqueue.h>

	#include <net/inet_sock.h>
	#include <net/sock.h>
	#include <net/tcp_states.h>
	#include <net/timewait_sock.h>

	#include <asm/atomic.h>

	struct inet_hashinfo;

	#define INET_TWDR_RECYCLE_SLOTS_LOG 5
	#define INET_TWDR_RECYCLE_SLOTS (1 << INET_TWDR_RECYCLE_SLOTS_LOG)

	/*
	* If time > 4sec, it is "slow" path, no recycling is required,
	* so that we select tick to get range about 4 seconds.
	*/
	#if HZ <= 16 \|\| HZ > 4096
	# error Unsupported: HZ <= 16 or HZ > 4096
	#elif HZ <= 32
	# define INET_TWDR_RECYCLE_TICK (5 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#elif HZ <= 64
	# define INET_TWDR_RECYCLE_TICK (6 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#elif HZ <= 128
	# define INET_TWDR_RECYCLE_TICK (7 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#elif HZ <= 256
	# define INET_TWDR_RECYCLE_TICK (8 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#elif HZ <= 512
	# define INET_TWDR_RECYCLE_TICK (9 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#elif HZ <= 1024
	# define INET_TWDR_RECYCLE_TICK (10 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#elif HZ <= 2048
	# define INET_TWDR_RECYCLE_TICK (11 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#else
	# define INET_TWDR_RECYCLE_TICK (12 + 2 - INET_TWDR_RECYCLE_SLOTS_LOG)
	#endif

	/* TIME_WAIT reaping mechanism. */
	#define INET_TWDR_TWKILL_SLOTS 8 /* Please keep this a power of 2. */

	#define INET_TWDR_TWKILL_QUOTA 100

	struct inet_timewait_death_row {
	/* Short-time timewait calendar */
	int twcal_hand;
	unsigned long twcal_jiffie;
	struct timer_list twcal_timer;
	struct hlist_head twcal_row[INET_TWDR_RECYCLE_SLOTS];

	spinlock_t death_lock;
	int tw_count;
	int period;
	u32 thread_slots;
	struct work_struct twkill_work;
	struct timer_list tw_timer;
	int slot;
	struct hlist_head cells[INET_TWDR_TWKILL_SLOTS];
	struct inet_hashinfo *hashinfo;
	int sysctl_tw_recycle;
	int sysctl_max_tw_buckets;
	};

	extern void inet_twdr_hangman(unsigned long data);
	extern void inet_twdr_twkill_work(struct work_struct *work);
	extern void inet_twdr_twcal_tick(unsigned long data);

	#if (BITS_PER_LONG == 64)
	#define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 8
	#else
	#define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 4
	#endif

	struct inet_bind_bucket;

	/*
	* This is a TIME_WAIT sock. It works around the memory consumption
	* problems of sockets in such a state on heavily loaded servers, but
	* without violating the protocol specification.
	*/
	struct inet_timewait_sock {
	/*
	* Now struct sock also uses sock_common, so please just
	* don't add nothing before this first member (__tw_common) --acme
	*/
	struct sock_common __tw_common;
	#define tw_family __tw_common.skc_family
	#define tw_state __tw_common.skc_state
	#define tw_reuse __tw_common.skc_reuse
	#define tw_bound_dev_if __tw_common.skc_bound_dev_if
	#define tw_node __tw_common.skc_nulls_node
	#define tw_bind_node __tw_common.skc_bind_node
	#define tw_refcnt __tw_common.skc_refcnt
	#define tw_hash __tw_common.skc_hash
	#define tw_prot __tw_common.skc_prot
	#define tw_net __tw_common.skc_net
	int tw_timeout;
	volatile unsigned char tw_substate;
	/* 3 bits hole, try to pack */
	unsigned char tw_rcv_wscale;
	/* Socket demultiplex comparisons on incoming packets. */
	/* these five are in inet_sock */
	__be16 tw_sport;
	__be32 tw_daddr __attribute__((aligned(INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES)));
	__be32 tw_rcv_saddr;
	__be16 tw_dport;
	__u16 tw_num;
	kmemcheck_bitfield_begin(flags);
	/* And these are ours. */
	unsigned int tw_ipv6only : 1,
	tw_transparent : 1,
	tw_pad : 14, /* 14 bits hole */
	tw_ipv6_offset : 16;
	kmemcheck_bitfield_end(flags);
	unsigned long tw_ttd;
	struct inet_bind_bucket *tw_tb;
	struct hlist_node tw_death_node;
	};

	static inline void inet_twsk_add_node_rcu(struct inet_timewait_sock *tw,
	struct hlist_nulls_head *list)
	{
	hlist_nulls_add_head_rcu(&tw->tw_node, list);
	}

	static inline void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
	struct hlist_head *list)
	{
	hlist_add_head(&tw->tw_bind_node, list);
	}

	static inline int inet_twsk_dead_hashed(const struct inet_timewait_sock *tw)
	{
	return !hlist_unhashed(&tw->tw_death_node);
	}

	static inline void inet_twsk_dead_node_init(struct inet_timewait_sock *tw)
	{
	tw->tw_death_node.pprev = NULL;
	}

	static inline void __inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
	{
	__hlist_del(&tw->tw_death_node);
	inet_twsk_dead_node_init(tw);
	}

	static inline int inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
	{
	if (inet_twsk_dead_hashed(tw)) {
	__inet_twsk_del_dead_node(tw);
	return 1;
	}
	return 0;
	}

	#define inet_twsk_for_each(tw, node, head) \
	hlist_nulls_for_each_entry(tw, node, head, tw_node)

	#define inet_twsk_for_each_inmate(tw, node, jail) \
	hlist_for_each_entry(tw, node, jail, tw_death_node)

	#define inet_twsk_for_each_inmate_safe(tw, node, safe, jail) \
	hlist_for_each_entry_safe(tw, node, safe, jail, tw_death_node)

	static inline struct inet_timewait_sock inet_twsk(const struct sock sk)
	{
	return (struct inet_timewait_sock *)sk;
	}

	static inline __be32 inet_rcv_saddr(const struct sock *sk)
	{
	return likely(sk->sk_state != TCP_TIME_WAIT) ?
	inet_sk(sk)->rcv_saddr : inet_twsk(sk)->tw_rcv_saddr;
	}

	extern void inet_twsk_put(struct inet_timewait_sock *tw);

	extern struct inet_timewait_sock inet_twsk_alloc(const struct sock sk,
	const int state);

	extern void __inet_twsk_hashdance(struct inet_timewait_sock *tw,
	struct sock *sk,
	struct inet_hashinfo *hashinfo);

	extern void inet_twsk_schedule(struct inet_timewait_sock *tw,
	struct inet_timewait_death_row *twdr,
	const int timeo, const int timewait_len);
	extern void inet_twsk_deschedule(struct inet_timewait_sock *tw,
	struct inet_timewait_death_row *twdr);

	extern void inet_twsk_purge(struct net net, struct inet_hashinfo hashinfo,
	struct inet_timewait_death_row *twdr, int family);

	static inline
	struct net twsk_net(const struct inet_timewait_sock twsk)
	{
	#ifdef CONFIG_NET_NS
	return twsk->tw_net;
	#else
	return &init_net;
	#endif
	}

	static inline
	void twsk_net_set(struct inet_timewait_sock twsk, struct net net)
	{
	#ifdef CONFIG_NET_NS
	twsk->tw_net = net;
	#endif
	}
	#endif /* _INET_TIMEWAIT_SOCK_ */