/* * 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/config.h> #include <linux/ip.h> #include <linux/list.h> #include <linux/module.h> #include <linux/timer.h> #include <linux/types.h> #include <linux/workqueue.h> #include <net/sock.h> #include <net/tcp_states.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; int 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(void *data); 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_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 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 */ __u16 tw_sport; __u32 tw_daddr __attribute__((aligned(INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES))); __u32 tw_rcv_saddr; __u16 tw_dport; __u16 tw_num; /* And these are ours. */ __u8 tw_ipv6only:1; /* 31 bits hole, try to pack */ int tw_timeout; unsigned long tw_ttd; struct inet_bind_bucket *tw_tb; struct hlist_node tw_death_node; }; static inline void inet_twsk_add_node(struct inet_timewait_sock *tw, struct hlist_head *list) { hlist_add_head(&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 tw->tw_death_node.pprev != NULL; } 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_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 u32 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; } static inline void inet_twsk_put(struct inet_timewait_sock *tw) { if (atomic_dec_and_test(&tw->tw_refcnt)) { struct module *owner = tw->tw_prot->owner; #ifdef SOCK_REFCNT_DEBUG printk(KERN_DEBUG "%s timewait_sock %p released\n", tw->tw_prot->name, tw); #endif kmem_cache_free(tw->tw_prot->twsk_slab, tw); module_put(owner); } } extern struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk, const int state); extern void __inet_twsk_kill(struct inet_timewait_sock *tw, struct inet_hashinfo *hashinfo); 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); #endif /* _INET_TIMEWAIT_SOCK_ */