include/net/inet_timewait

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This source file includes following definitions.
inet_tw_time_stamp
inet_twsk_dead_hashed
inet_twsk_dead_node_init
__inet_twsk_del_dead_node
inet_twsk_del_dead_node
inet_twsk
twsk_net
twsk_net_set
/*
 * 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/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 <linux/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

static inline u32 inet_tw_time_stamp(void)
{
        return jiffies;
}

/* 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;
};

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

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_ipv6only             __tw_common.skc_ipv6only
#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
#define tw_daddr                __tw_common.skc_daddr
#define tw_v6_daddr             __tw_common.skc_v6_daddr
#define tw_rcv_saddr            __tw_common.skc_rcv_saddr
#define tw_v6_rcv_saddr         __tw_common.skc_v6_rcv_saddr
#define tw_dport                __tw_common.skc_dport
#define tw_num                  __tw_common.skc_num

        int                     tw_timeout;
        volatile unsigned char  tw_substate;
        unsigned char           tw_rcv_wscale;

        /* Socket demultiplex comparisons on incoming packets. */
        /* these three are in inet_sock */
        __be16                  tw_sport;
        kmemcheck_bitfield_begin(flags);
        /* And these are ours. */
        unsigned int            tw_pad0         : 1,    /* 1 bit hole */
                                tw_transparent  : 1,
                                tw_flowlabel    : 20,
                                tw_pad          : 2,    /* 2 bits hole */
                                tw_tos          : 8;
        kmemcheck_bitfield_end(flags);
        u32                     tw_ttd;
        struct inet_bind_bucket *tw_tb;
        struct hlist_node       tw_death_node;
};
#define tw_tclass tw_tos

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, jail) \
        hlist_for_each_entry(tw, jail, tw_death_node)

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

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

void inet_twsk_free(struct inet_timewait_sock *tw);
void inet_twsk_put(struct inet_timewait_sock *tw);

int inet_twsk_unhash(struct inet_timewait_sock *tw);

int inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
                          struct inet_hashinfo *hashinfo);

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

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

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

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

static inline
struct net *twsk_net(const struct inet_timewait_sock *twsk)
{
        return read_pnet(&twsk->tw_net);
}

static inline
void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
{
        write_pnet(&twsk->tw_net, net);
}
#endif  /* _INET_TIMEWAIT_SOCK_ */
/* [<][>][^][v][top][bottom][index][help] */
root/include/net/inet_timewait_sock.h

INCLUDED FROM

DEFINITIONS
