| /* |
| * 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/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; |
| 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; |
| /* 15 bits hole, try to pack */ |
| __u16 tw_ipv6_offset; |
| 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 !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_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_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_ */ |