![Andrew Morton](/assets/img/avatar_default.png)
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
945 lines
22 KiB
C
945 lines
22 KiB
C
/*
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* IPVS An implementation of the IP virtual server support for the
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* LINUX operating system. IPVS is now implemented as a module
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* over the Netfilter framework. IPVS can be used to build a
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* high-performance and highly available server based on a
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* cluster of servers.
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*
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* Version: $Id: ip_vs_conn.c,v 1.31 2003/04/18 09:03:16 wensong Exp $
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*
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* Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
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* Peter Kese <peter.kese@ijs.si>
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* Julian Anastasov <ja@ssi.bg>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
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* with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
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* and others. Many code here is taken from IP MASQ code of kernel 2.2.
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*
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* Changes:
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*
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*/
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#include <linux/interrupt.h>
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#include <linux/in.h>
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#include <linux/net.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/vmalloc.h>
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#include <linux/proc_fs.h> /* for proc_net_* */
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#include <linux/seq_file.h>
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#include <linux/jhash.h>
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#include <linux/random.h>
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#include <net/ip_vs.h>
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/*
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* Connection hash table: for input and output packets lookups of IPVS
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*/
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static struct list_head *ip_vs_conn_tab;
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/* SLAB cache for IPVS connections */
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static kmem_cache_t *ip_vs_conn_cachep __read_mostly;
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/* counter for current IPVS connections */
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static atomic_t ip_vs_conn_count = ATOMIC_INIT(0);
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/* counter for no client port connections */
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static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0);
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/* random value for IPVS connection hash */
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static unsigned int ip_vs_conn_rnd;
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/*
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* Fine locking granularity for big connection hash table
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*/
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#define CT_LOCKARRAY_BITS 4
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#define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS)
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#define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1)
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struct ip_vs_aligned_lock
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{
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rwlock_t l;
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} __attribute__((__aligned__(SMP_CACHE_BYTES)));
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/* lock array for conn table */
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static struct ip_vs_aligned_lock
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__ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned;
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static inline void ct_read_lock(unsigned key)
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{
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read_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_read_unlock(unsigned key)
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{
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read_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_write_lock(unsigned key)
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{
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write_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_write_unlock(unsigned key)
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{
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write_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_read_lock_bh(unsigned key)
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{
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read_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_read_unlock_bh(unsigned key)
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{
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read_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_write_lock_bh(unsigned key)
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{
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write_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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static inline void ct_write_unlock_bh(unsigned key)
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{
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write_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
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}
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/*
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* Returns hash value for IPVS connection entry
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*/
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static unsigned int ip_vs_conn_hashkey(unsigned proto, __u32 addr, __u16 port)
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{
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return jhash_3words(addr, port, proto, ip_vs_conn_rnd)
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& IP_VS_CONN_TAB_MASK;
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}
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/*
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* Hashes ip_vs_conn in ip_vs_conn_tab by proto,addr,port.
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* returns bool success.
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*/
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static inline int ip_vs_conn_hash(struct ip_vs_conn *cp)
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{
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unsigned hash;
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int ret;
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/* Hash by protocol, client address and port */
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hash = ip_vs_conn_hashkey(cp->protocol, cp->caddr, cp->cport);
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ct_write_lock(hash);
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if (!(cp->flags & IP_VS_CONN_F_HASHED)) {
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list_add(&cp->c_list, &ip_vs_conn_tab[hash]);
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cp->flags |= IP_VS_CONN_F_HASHED;
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atomic_inc(&cp->refcnt);
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ret = 1;
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} else {
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IP_VS_ERR("ip_vs_conn_hash(): request for already hashed, "
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"called from %p\n", __builtin_return_address(0));
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ret = 0;
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}
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ct_write_unlock(hash);
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return ret;
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}
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/*
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* UNhashes ip_vs_conn from ip_vs_conn_tab.
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* returns bool success.
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*/
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static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp)
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{
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unsigned hash;
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int ret;
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/* unhash it and decrease its reference counter */
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hash = ip_vs_conn_hashkey(cp->protocol, cp->caddr, cp->cport);
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ct_write_lock(hash);
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if (cp->flags & IP_VS_CONN_F_HASHED) {
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list_del(&cp->c_list);
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cp->flags &= ~IP_VS_CONN_F_HASHED;
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atomic_dec(&cp->refcnt);
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ret = 1;
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} else
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ret = 0;
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ct_write_unlock(hash);
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return ret;
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}
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/*
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* Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
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* Called for pkts coming from OUTside-to-INside.
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* s_addr, s_port: pkt source address (foreign host)
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* d_addr, d_port: pkt dest address (load balancer)
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*/
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static inline struct ip_vs_conn *__ip_vs_conn_in_get
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(int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
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{
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unsigned hash;
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struct ip_vs_conn *cp;
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hash = ip_vs_conn_hashkey(protocol, s_addr, s_port);
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ct_read_lock(hash);
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list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
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if (s_addr==cp->caddr && s_port==cp->cport &&
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d_port==cp->vport && d_addr==cp->vaddr &&
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((!s_port) ^ (!(cp->flags & IP_VS_CONN_F_NO_CPORT))) &&
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protocol==cp->protocol) {
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/* HIT */
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atomic_inc(&cp->refcnt);
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ct_read_unlock(hash);
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return cp;
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}
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}
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ct_read_unlock(hash);
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return NULL;
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}
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struct ip_vs_conn *ip_vs_conn_in_get
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(int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
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{
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struct ip_vs_conn *cp;
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cp = __ip_vs_conn_in_get(protocol, s_addr, s_port, d_addr, d_port);
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if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt))
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cp = __ip_vs_conn_in_get(protocol, s_addr, 0, d_addr, d_port);
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IP_VS_DBG(9, "lookup/in %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n",
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ip_vs_proto_name(protocol),
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NIPQUAD(s_addr), ntohs(s_port),
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NIPQUAD(d_addr), ntohs(d_port),
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cp?"hit":"not hit");
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return cp;
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}
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/* Get reference to connection template */
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struct ip_vs_conn *ip_vs_ct_in_get
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(int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
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{
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unsigned hash;
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struct ip_vs_conn *cp;
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hash = ip_vs_conn_hashkey(protocol, s_addr, s_port);
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ct_read_lock(hash);
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list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
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if (s_addr==cp->caddr && s_port==cp->cport &&
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d_port==cp->vport && d_addr==cp->vaddr &&
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cp->flags & IP_VS_CONN_F_TEMPLATE &&
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protocol==cp->protocol) {
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/* HIT */
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atomic_inc(&cp->refcnt);
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goto out;
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}
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}
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cp = NULL;
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out:
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ct_read_unlock(hash);
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IP_VS_DBG(9, "template lookup/in %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n",
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ip_vs_proto_name(protocol),
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NIPQUAD(s_addr), ntohs(s_port),
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NIPQUAD(d_addr), ntohs(d_port),
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cp?"hit":"not hit");
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return cp;
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}
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/*
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* Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
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* Called for pkts coming from inside-to-OUTside.
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* s_addr, s_port: pkt source address (inside host)
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* d_addr, d_port: pkt dest address (foreign host)
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*/
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struct ip_vs_conn *ip_vs_conn_out_get
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(int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
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{
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unsigned hash;
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struct ip_vs_conn *cp, *ret=NULL;
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/*
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* Check for "full" addressed entries
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*/
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hash = ip_vs_conn_hashkey(protocol, d_addr, d_port);
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ct_read_lock(hash);
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list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
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if (d_addr == cp->caddr && d_port == cp->cport &&
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s_port == cp->dport && s_addr == cp->daddr &&
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protocol == cp->protocol) {
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/* HIT */
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atomic_inc(&cp->refcnt);
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ret = cp;
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break;
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}
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}
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ct_read_unlock(hash);
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IP_VS_DBG(9, "lookup/out %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n",
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ip_vs_proto_name(protocol),
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NIPQUAD(s_addr), ntohs(s_port),
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NIPQUAD(d_addr), ntohs(d_port),
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ret?"hit":"not hit");
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return ret;
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}
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/*
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* Put back the conn and restart its timer with its timeout
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*/
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void ip_vs_conn_put(struct ip_vs_conn *cp)
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{
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/* reset it expire in its timeout */
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mod_timer(&cp->timer, jiffies+cp->timeout);
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__ip_vs_conn_put(cp);
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}
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/*
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* Fill a no_client_port connection with a client port number
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*/
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void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __u16 cport)
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{
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if (ip_vs_conn_unhash(cp)) {
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spin_lock(&cp->lock);
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if (cp->flags & IP_VS_CONN_F_NO_CPORT) {
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atomic_dec(&ip_vs_conn_no_cport_cnt);
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cp->flags &= ~IP_VS_CONN_F_NO_CPORT;
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cp->cport = cport;
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}
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spin_unlock(&cp->lock);
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/* hash on new dport */
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ip_vs_conn_hash(cp);
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}
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}
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/*
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* Bind a connection entry with the corresponding packet_xmit.
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* Called by ip_vs_conn_new.
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*/
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static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp)
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{
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switch (IP_VS_FWD_METHOD(cp)) {
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case IP_VS_CONN_F_MASQ:
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cp->packet_xmit = ip_vs_nat_xmit;
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break;
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case IP_VS_CONN_F_TUNNEL:
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cp->packet_xmit = ip_vs_tunnel_xmit;
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break;
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case IP_VS_CONN_F_DROUTE:
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cp->packet_xmit = ip_vs_dr_xmit;
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break;
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case IP_VS_CONN_F_LOCALNODE:
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cp->packet_xmit = ip_vs_null_xmit;
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break;
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case IP_VS_CONN_F_BYPASS:
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cp->packet_xmit = ip_vs_bypass_xmit;
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break;
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}
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}
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static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest)
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{
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return atomic_read(&dest->activeconns)
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+ atomic_read(&dest->inactconns);
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}
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/*
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* Bind a connection entry with a virtual service destination
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* Called just after a new connection entry is created.
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*/
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static inline void
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ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
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{
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/* if dest is NULL, then return directly */
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if (!dest)
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return;
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/* Increase the refcnt counter of the dest */
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atomic_inc(&dest->refcnt);
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/* Bind with the destination and its corresponding transmitter */
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cp->flags |= atomic_read(&dest->conn_flags);
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cp->dest = dest;
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IP_VS_DBG(7, "Bind-dest %s c:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d "
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"d:%u.%u.%u.%u:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
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"dest->refcnt:%d\n",
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ip_vs_proto_name(cp->protocol),
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NIPQUAD(cp->caddr), ntohs(cp->cport),
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NIPQUAD(cp->vaddr), ntohs(cp->vport),
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NIPQUAD(cp->daddr), ntohs(cp->dport),
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ip_vs_fwd_tag(cp), cp->state,
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cp->flags, atomic_read(&cp->refcnt),
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atomic_read(&dest->refcnt));
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/* Update the connection counters */
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if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
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/* It is a normal connection, so increase the inactive
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connection counter because it is in TCP SYNRECV
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state (inactive) or other protocol inacive state */
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atomic_inc(&dest->inactconns);
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} else {
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/* It is a persistent connection/template, so increase
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the peristent connection counter */
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atomic_inc(&dest->persistconns);
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}
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if (dest->u_threshold != 0 &&
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ip_vs_dest_totalconns(dest) >= dest->u_threshold)
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dest->flags |= IP_VS_DEST_F_OVERLOAD;
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}
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/*
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* Unbind a connection entry with its VS destination
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* Called by the ip_vs_conn_expire function.
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*/
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static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
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{
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struct ip_vs_dest *dest = cp->dest;
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if (!dest)
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return;
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IP_VS_DBG(7, "Unbind-dest %s c:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d "
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"d:%u.%u.%u.%u:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
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"dest->refcnt:%d\n",
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ip_vs_proto_name(cp->protocol),
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NIPQUAD(cp->caddr), ntohs(cp->cport),
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NIPQUAD(cp->vaddr), ntohs(cp->vport),
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NIPQUAD(cp->daddr), ntohs(cp->dport),
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ip_vs_fwd_tag(cp), cp->state,
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cp->flags, atomic_read(&cp->refcnt),
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atomic_read(&dest->refcnt));
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|
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/* Update the connection counters */
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if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
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/* It is a normal connection, so decrease the inactconns
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or activeconns counter */
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if (cp->flags & IP_VS_CONN_F_INACTIVE) {
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atomic_dec(&dest->inactconns);
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} else {
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atomic_dec(&dest->activeconns);
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}
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} else {
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/* It is a persistent connection/template, so decrease
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the peristent connection counter */
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atomic_dec(&dest->persistconns);
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}
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if (dest->l_threshold != 0) {
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if (ip_vs_dest_totalconns(dest) < dest->l_threshold)
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dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
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} else if (dest->u_threshold != 0) {
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if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3)
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dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
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} else {
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if (dest->flags & IP_VS_DEST_F_OVERLOAD)
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dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
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}
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/*
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* Simply decrease the refcnt of the dest, because the
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* dest will be either in service's destination list
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* or in the trash.
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*/
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atomic_dec(&dest->refcnt);
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}
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|
|
|
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/*
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* Checking if the destination of a connection template is available.
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* If available, return 1, otherwise invalidate this connection
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* template and return 0.
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*/
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int ip_vs_check_template(struct ip_vs_conn *ct)
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{
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struct ip_vs_dest *dest = ct->dest;
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|
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/*
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* Checking the dest server status.
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*/
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if ((dest == NULL) ||
|
|
!(dest->flags & IP_VS_DEST_F_AVAILABLE) ||
|
|
(sysctl_ip_vs_expire_quiescent_template &&
|
|
(atomic_read(&dest->weight) == 0))) {
|
|
IP_VS_DBG(9, "check_template: dest not available for "
|
|
"protocol %s s:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d "
|
|
"-> d:%u.%u.%u.%u:%d\n",
|
|
ip_vs_proto_name(ct->protocol),
|
|
NIPQUAD(ct->caddr), ntohs(ct->cport),
|
|
NIPQUAD(ct->vaddr), ntohs(ct->vport),
|
|
NIPQUAD(ct->daddr), ntohs(ct->dport));
|
|
|
|
/*
|
|
* Invalidate the connection template
|
|
*/
|
|
if (ct->vport != 65535) {
|
|
if (ip_vs_conn_unhash(ct)) {
|
|
ct->dport = 65535;
|
|
ct->vport = 65535;
|
|
ct->cport = 0;
|
|
ip_vs_conn_hash(ct);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Simply decrease the refcnt of the template,
|
|
* don't restart its timer.
|
|
*/
|
|
atomic_dec(&ct->refcnt);
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static void ip_vs_conn_expire(unsigned long data)
|
|
{
|
|
struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
|
|
|
|
cp->timeout = 60*HZ;
|
|
|
|
/*
|
|
* hey, I'm using it
|
|
*/
|
|
atomic_inc(&cp->refcnt);
|
|
|
|
/*
|
|
* do I control anybody?
|
|
*/
|
|
if (atomic_read(&cp->n_control))
|
|
goto expire_later;
|
|
|
|
/*
|
|
* unhash it if it is hashed in the conn table
|
|
*/
|
|
if (!ip_vs_conn_unhash(cp))
|
|
goto expire_later;
|
|
|
|
/*
|
|
* refcnt==1 implies I'm the only one referrer
|
|
*/
|
|
if (likely(atomic_read(&cp->refcnt) == 1)) {
|
|
/* delete the timer if it is activated by other users */
|
|
if (timer_pending(&cp->timer))
|
|
del_timer(&cp->timer);
|
|
|
|
/* does anybody control me? */
|
|
if (cp->control)
|
|
ip_vs_control_del(cp);
|
|
|
|
if (unlikely(cp->app != NULL))
|
|
ip_vs_unbind_app(cp);
|
|
ip_vs_unbind_dest(cp);
|
|
if (cp->flags & IP_VS_CONN_F_NO_CPORT)
|
|
atomic_dec(&ip_vs_conn_no_cport_cnt);
|
|
atomic_dec(&ip_vs_conn_count);
|
|
|
|
kmem_cache_free(ip_vs_conn_cachep, cp);
|
|
return;
|
|
}
|
|
|
|
/* hash it back to the table */
|
|
ip_vs_conn_hash(cp);
|
|
|
|
expire_later:
|
|
IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n",
|
|
atomic_read(&cp->refcnt)-1,
|
|
atomic_read(&cp->n_control));
|
|
|
|
ip_vs_conn_put(cp);
|
|
}
|
|
|
|
|
|
void ip_vs_conn_expire_now(struct ip_vs_conn *cp)
|
|
{
|
|
if (del_timer(&cp->timer))
|
|
mod_timer(&cp->timer, jiffies);
|
|
}
|
|
|
|
|
|
/*
|
|
* Create a new connection entry and hash it into the ip_vs_conn_tab
|
|
*/
|
|
struct ip_vs_conn *
|
|
ip_vs_conn_new(int proto, __u32 caddr, __u16 cport, __u32 vaddr, __u16 vport,
|
|
__u32 daddr, __u16 dport, unsigned flags,
|
|
struct ip_vs_dest *dest)
|
|
{
|
|
struct ip_vs_conn *cp;
|
|
struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
|
|
|
|
cp = kmem_cache_alloc(ip_vs_conn_cachep, GFP_ATOMIC);
|
|
if (cp == NULL) {
|
|
IP_VS_ERR_RL("ip_vs_conn_new: no memory available.\n");
|
|
return NULL;
|
|
}
|
|
|
|
memset(cp, 0, sizeof(*cp));
|
|
INIT_LIST_HEAD(&cp->c_list);
|
|
init_timer(&cp->timer);
|
|
cp->timer.data = (unsigned long)cp;
|
|
cp->timer.function = ip_vs_conn_expire;
|
|
cp->protocol = proto;
|
|
cp->caddr = caddr;
|
|
cp->cport = cport;
|
|
cp->vaddr = vaddr;
|
|
cp->vport = vport;
|
|
cp->daddr = daddr;
|
|
cp->dport = dport;
|
|
cp->flags = flags;
|
|
spin_lock_init(&cp->lock);
|
|
|
|
/*
|
|
* Set the entry is referenced by the current thread before hashing
|
|
* it in the table, so that other thread run ip_vs_random_dropentry
|
|
* but cannot drop this entry.
|
|
*/
|
|
atomic_set(&cp->refcnt, 1);
|
|
|
|
atomic_set(&cp->n_control, 0);
|
|
atomic_set(&cp->in_pkts, 0);
|
|
|
|
atomic_inc(&ip_vs_conn_count);
|
|
if (flags & IP_VS_CONN_F_NO_CPORT)
|
|
atomic_inc(&ip_vs_conn_no_cport_cnt);
|
|
|
|
/* Bind the connection with a destination server */
|
|
ip_vs_bind_dest(cp, dest);
|
|
|
|
/* Set its state and timeout */
|
|
cp->state = 0;
|
|
cp->timeout = 3*HZ;
|
|
|
|
/* Bind its packet transmitter */
|
|
ip_vs_bind_xmit(cp);
|
|
|
|
if (unlikely(pp && atomic_read(&pp->appcnt)))
|
|
ip_vs_bind_app(cp, pp);
|
|
|
|
/* Hash it in the ip_vs_conn_tab finally */
|
|
ip_vs_conn_hash(cp);
|
|
|
|
return cp;
|
|
}
|
|
|
|
|
|
/*
|
|
* /proc/net/ip_vs_conn entries
|
|
*/
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos)
|
|
{
|
|
int idx;
|
|
struct ip_vs_conn *cp;
|
|
|
|
for(idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) {
|
|
ct_read_lock_bh(idx);
|
|
list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
|
|
if (pos-- == 0) {
|
|
seq->private = &ip_vs_conn_tab[idx];
|
|
return cp;
|
|
}
|
|
}
|
|
ct_read_unlock_bh(idx);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
seq->private = NULL;
|
|
return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN;
|
|
}
|
|
|
|
static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
struct ip_vs_conn *cp = v;
|
|
struct list_head *e, *l = seq->private;
|
|
int idx;
|
|
|
|
++*pos;
|
|
if (v == SEQ_START_TOKEN)
|
|
return ip_vs_conn_array(seq, 0);
|
|
|
|
/* more on same hash chain? */
|
|
if ((e = cp->c_list.next) != l)
|
|
return list_entry(e, struct ip_vs_conn, c_list);
|
|
|
|
idx = l - ip_vs_conn_tab;
|
|
ct_read_unlock_bh(idx);
|
|
|
|
while (++idx < IP_VS_CONN_TAB_SIZE) {
|
|
ct_read_lock_bh(idx);
|
|
list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
|
|
seq->private = &ip_vs_conn_tab[idx];
|
|
return cp;
|
|
}
|
|
ct_read_unlock_bh(idx);
|
|
}
|
|
seq->private = NULL;
|
|
return NULL;
|
|
}
|
|
|
|
static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v)
|
|
{
|
|
struct list_head *l = seq->private;
|
|
|
|
if (l)
|
|
ct_read_unlock_bh(l - ip_vs_conn_tab);
|
|
}
|
|
|
|
static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
|
|
if (v == SEQ_START_TOKEN)
|
|
seq_puts(seq,
|
|
"Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n");
|
|
else {
|
|
const struct ip_vs_conn *cp = v;
|
|
|
|
seq_printf(seq,
|
|
"%-3s %08X %04X %08X %04X %08X %04X %-11s %7lu\n",
|
|
ip_vs_proto_name(cp->protocol),
|
|
ntohl(cp->caddr), ntohs(cp->cport),
|
|
ntohl(cp->vaddr), ntohs(cp->vport),
|
|
ntohl(cp->daddr), ntohs(cp->dport),
|
|
ip_vs_state_name(cp->protocol, cp->state),
|
|
(cp->timer.expires-jiffies)/HZ);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct seq_operations ip_vs_conn_seq_ops = {
|
|
.start = ip_vs_conn_seq_start,
|
|
.next = ip_vs_conn_seq_next,
|
|
.stop = ip_vs_conn_seq_stop,
|
|
.show = ip_vs_conn_seq_show,
|
|
};
|
|
|
|
static int ip_vs_conn_open(struct inode *inode, struct file *file)
|
|
{
|
|
return seq_open(file, &ip_vs_conn_seq_ops);
|
|
}
|
|
|
|
static struct file_operations ip_vs_conn_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = ip_vs_conn_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release,
|
|
};
|
|
#endif
|
|
|
|
|
|
/*
|
|
* Randomly drop connection entries before running out of memory
|
|
*/
|
|
static inline int todrop_entry(struct ip_vs_conn *cp)
|
|
{
|
|
/*
|
|
* The drop rate array needs tuning for real environments.
|
|
* Called from timer bh only => no locking
|
|
*/
|
|
static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
|
|
static char todrop_counter[9] = {0};
|
|
int i;
|
|
|
|
/* if the conn entry hasn't lasted for 60 seconds, don't drop it.
|
|
This will leave enough time for normal connection to get
|
|
through. */
|
|
if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ))
|
|
return 0;
|
|
|
|
/* Don't drop the entry if its number of incoming packets is not
|
|
located in [0, 8] */
|
|
i = atomic_read(&cp->in_pkts);
|
|
if (i > 8 || i < 0) return 0;
|
|
|
|
if (!todrop_rate[i]) return 0;
|
|
if (--todrop_counter[i] > 0) return 0;
|
|
|
|
todrop_counter[i] = todrop_rate[i];
|
|
return 1;
|
|
}
|
|
|
|
/* Called from keventd and must protect itself from softirqs */
|
|
void ip_vs_random_dropentry(void)
|
|
{
|
|
int idx;
|
|
struct ip_vs_conn *cp;
|
|
|
|
/*
|
|
* Randomly scan 1/32 of the whole table every second
|
|
*/
|
|
for (idx = 0; idx < (IP_VS_CONN_TAB_SIZE>>5); idx++) {
|
|
unsigned hash = net_random() & IP_VS_CONN_TAB_MASK;
|
|
|
|
/*
|
|
* Lock is actually needed in this loop.
|
|
*/
|
|
ct_write_lock_bh(hash);
|
|
|
|
list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
|
|
if (cp->flags & IP_VS_CONN_F_TEMPLATE)
|
|
/* connection template */
|
|
continue;
|
|
|
|
if (cp->protocol == IPPROTO_TCP) {
|
|
switch(cp->state) {
|
|
case IP_VS_TCP_S_SYN_RECV:
|
|
case IP_VS_TCP_S_SYNACK:
|
|
break;
|
|
|
|
case IP_VS_TCP_S_ESTABLISHED:
|
|
if (todrop_entry(cp))
|
|
break;
|
|
continue;
|
|
|
|
default:
|
|
continue;
|
|
}
|
|
} else {
|
|
if (!todrop_entry(cp))
|
|
continue;
|
|
}
|
|
|
|
IP_VS_DBG(4, "del connection\n");
|
|
ip_vs_conn_expire_now(cp);
|
|
if (cp->control) {
|
|
IP_VS_DBG(4, "del conn template\n");
|
|
ip_vs_conn_expire_now(cp->control);
|
|
}
|
|
}
|
|
ct_write_unlock_bh(hash);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Flush all the connection entries in the ip_vs_conn_tab
|
|
*/
|
|
static void ip_vs_conn_flush(void)
|
|
{
|
|
int idx;
|
|
struct ip_vs_conn *cp;
|
|
|
|
flush_again:
|
|
for (idx=0; idx<IP_VS_CONN_TAB_SIZE; idx++) {
|
|
/*
|
|
* Lock is actually needed in this loop.
|
|
*/
|
|
ct_write_lock_bh(idx);
|
|
|
|
list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
|
|
|
|
IP_VS_DBG(4, "del connection\n");
|
|
ip_vs_conn_expire_now(cp);
|
|
if (cp->control) {
|
|
IP_VS_DBG(4, "del conn template\n");
|
|
ip_vs_conn_expire_now(cp->control);
|
|
}
|
|
}
|
|
ct_write_unlock_bh(idx);
|
|
}
|
|
|
|
/* the counter may be not NULL, because maybe some conn entries
|
|
are run by slow timer handler or unhashed but still referred */
|
|
if (atomic_read(&ip_vs_conn_count) != 0) {
|
|
schedule();
|
|
goto flush_again;
|
|
}
|
|
}
|
|
|
|
|
|
int ip_vs_conn_init(void)
|
|
{
|
|
int idx;
|
|
|
|
/*
|
|
* Allocate the connection hash table and initialize its list heads
|
|
*/
|
|
ip_vs_conn_tab = vmalloc(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head));
|
|
if (!ip_vs_conn_tab)
|
|
return -ENOMEM;
|
|
|
|
/* Allocate ip_vs_conn slab cache */
|
|
ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn",
|
|
sizeof(struct ip_vs_conn), 0,
|
|
SLAB_HWCACHE_ALIGN, NULL, NULL);
|
|
if (!ip_vs_conn_cachep) {
|
|
vfree(ip_vs_conn_tab);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
IP_VS_INFO("Connection hash table configured "
|
|
"(size=%d, memory=%ldKbytes)\n",
|
|
IP_VS_CONN_TAB_SIZE,
|
|
(long)(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head))/1024);
|
|
IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
|
|
sizeof(struct ip_vs_conn));
|
|
|
|
for (idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) {
|
|
INIT_LIST_HEAD(&ip_vs_conn_tab[idx]);
|
|
}
|
|
|
|
for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) {
|
|
rwlock_init(&__ip_vs_conntbl_lock_array[idx].l);
|
|
}
|
|
|
|
proc_net_fops_create("ip_vs_conn", 0, &ip_vs_conn_fops);
|
|
|
|
/* calculate the random value for connection hash */
|
|
get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void ip_vs_conn_cleanup(void)
|
|
{
|
|
/* flush all the connection entries first */
|
|
ip_vs_conn_flush();
|
|
|
|
/* Release the empty cache */
|
|
kmem_cache_destroy(ip_vs_conn_cachep);
|
|
proc_net_remove("ip_vs_conn");
|
|
vfree(ip_vs_conn_tab);
|
|
}
|