/* * 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 /* 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); 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 #define tw_daddr __tw_common.skc_daddr #define tw_rcv_saddr __tw_common.skc_rcv_saddr #define tw_addrpair __tw_common.skc_addrpair #define tw_dport __tw_common.skc_dport #define tw_num __tw_common.skc_num #define tw_portpair __tw_common.skc_portpair 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_ipv6only : 1, tw_transparent : 1, tw_pad : 6, /* 6 bits hole */ tw_tos : 8, tw_ipv6_offset : 16; kmemcheck_bitfield_end(flags); unsigned long tw_ttd; struct inet_bind_bucket *tw_tb; struct hlist_node tw_death_node; }; #define tw_tclass tw_tos 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, 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; } static inline __be32 sk_rcv_saddr(const struct sock *sk) { /* both inet_sk() and inet_twsk() store rcv_saddr in skc_rcv_saddr */ return sk->__sk_common.skc_rcv_saddr; } extern void inet_twsk_put(struct inet_timewait_sock *tw); extern int inet_twsk_unhash(struct inet_timewait_sock *tw); extern int inet_twsk_bind_unhash(struct inet_timewait_sock *tw, struct inet_hashinfo *hashinfo); 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 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_ */