2 * IPVS An implementation of the IP virtual server support for the
3 * LINUX operating system. IPVS is now implemented as a module
4 * over the Netfilter framework. IPVS can be used to build a
5 * high-performance and highly available server based on a
8 * Version: $Id: ip_vs_conn.c,v 1.31 2003/04/18 09:03:16 wensong Exp $
10 * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
11 * Peter Kese <peter.kese@ijs.si>
12 * Julian Anastasov <ja@ssi.bg>
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
19 * The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
20 * with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
21 * and others. Many code here is taken from IP MASQ code of kernel 2.2.
27 #include <linux/kernel.h>
28 #include <linux/vmalloc.h>
29 #include <linux/proc_fs.h> /* for proc_net_* */
30 #include <linux/seq_file.h>
31 #include <linux/jhash.h>
32 #include <linux/random.h>
34 #include <net/ip_vs.h>
38 * Connection hash table: for input and output packets lookups of IPVS
40 static struct list_head *ip_vs_conn_tab;
42 /* SLAB cache for IPVS connections */
43 static kmem_cache_t *ip_vs_conn_cachep;
45 /* counter for current IPVS connections */
46 static atomic_t ip_vs_conn_count = ATOMIC_INIT(0);
48 /* counter for no client port connections */
49 static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0);
51 /* random value for IPVS connection hash */
52 static unsigned int ip_vs_conn_rnd;
55 * Fine locking granularity for big connection hash table
57 #define CT_LOCKARRAY_BITS 4
58 #define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS)
59 #define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1)
61 struct ip_vs_aligned_lock
64 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
66 /* lock array for conn table */
67 struct ip_vs_aligned_lock
68 __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned;
70 static inline void ct_read_lock(unsigned key)
72 read_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
75 static inline void ct_read_unlock(unsigned key)
77 read_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
80 static inline void ct_write_lock(unsigned key)
82 write_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
85 static inline void ct_write_unlock(unsigned key)
87 write_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
90 static inline void ct_read_lock_bh(unsigned key)
92 read_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
95 static inline void ct_read_unlock_bh(unsigned key)
97 read_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
100 static inline void ct_write_lock_bh(unsigned key)
102 write_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
105 static inline void ct_write_unlock_bh(unsigned key)
107 write_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
112 * Returns hash value for IPVS connection entry
114 static unsigned int ip_vs_conn_hashkey(unsigned proto, __u32 addr, __u16 port)
116 return jhash_3words(addr, port, proto, ip_vs_conn_rnd)
117 & IP_VS_CONN_TAB_MASK;
122 * Hashes ip_vs_conn in ip_vs_conn_tab by proto,addr,port.
123 * returns bool success.
125 static inline int ip_vs_conn_hash(struct ip_vs_conn *cp)
130 /* Hash by protocol, client address and port */
131 hash = ip_vs_conn_hashkey(cp->protocol, cp->caddr, cp->cport);
135 if (!(cp->flags & IP_VS_CONN_F_HASHED)) {
136 list_add(&cp->c_list, &ip_vs_conn_tab[hash]);
137 cp->flags |= IP_VS_CONN_F_HASHED;
138 atomic_inc(&cp->refcnt);
141 IP_VS_ERR("ip_vs_conn_hash(): request for already hashed, "
142 "called from %p\n", __builtin_return_address(0));
146 ct_write_unlock(hash);
153 * UNhashes ip_vs_conn from ip_vs_conn_tab.
154 * returns bool success.
156 static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp)
161 /* unhash it and decrease its reference counter */
162 hash = ip_vs_conn_hashkey(cp->protocol, cp->caddr, cp->cport);
166 if (cp->flags & IP_VS_CONN_F_HASHED) {
167 list_del(&cp->c_list);
168 cp->flags &= ~IP_VS_CONN_F_HASHED;
169 atomic_dec(&cp->refcnt);
174 ct_write_unlock(hash);
181 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
182 * Called for pkts coming from OUTside-to-INside.
183 * s_addr, s_port: pkt source address (foreign host)
184 * d_addr, d_port: pkt dest address (load balancer)
186 static inline struct ip_vs_conn *__ip_vs_conn_in_get
187 (int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
190 struct ip_vs_conn *cp;
192 hash = ip_vs_conn_hashkey(protocol, s_addr, s_port);
196 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
197 if (s_addr==cp->caddr && s_port==cp->cport &&
198 d_port==cp->vport && d_addr==cp->vaddr &&
199 protocol==cp->protocol) {
201 atomic_inc(&cp->refcnt);
202 ct_read_unlock(hash);
207 ct_read_unlock(hash);
212 struct ip_vs_conn *ip_vs_conn_in_get
213 (int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
215 struct ip_vs_conn *cp;
217 cp = __ip_vs_conn_in_get(protocol, s_addr, s_port, d_addr, d_port);
218 if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt))
219 cp = __ip_vs_conn_in_get(protocol, s_addr, 0, d_addr, d_port);
221 IP_VS_DBG(7, "lookup/in %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n",
222 ip_vs_proto_name(protocol),
223 NIPQUAD(s_addr), ntohs(s_port),
224 NIPQUAD(d_addr), ntohs(d_port),
232 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
233 * Called for pkts coming from inside-to-OUTside.
234 * s_addr, s_port: pkt source address (inside host)
235 * d_addr, d_port: pkt dest address (foreign host)
237 struct ip_vs_conn *ip_vs_conn_out_get
238 (int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port)
241 struct ip_vs_conn *cp, *ret=NULL;
244 * Check for "full" addressed entries
246 hash = ip_vs_conn_hashkey(protocol, d_addr, d_port);
250 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
251 if (d_addr == cp->caddr && d_port == cp->cport &&
252 s_port == cp->dport && s_addr == cp->daddr &&
253 protocol == cp->protocol) {
255 atomic_inc(&cp->refcnt);
261 ct_read_unlock(hash);
263 IP_VS_DBG(7, "lookup/out %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n",
264 ip_vs_proto_name(protocol),
265 NIPQUAD(s_addr), ntohs(s_port),
266 NIPQUAD(d_addr), ntohs(d_port),
267 ret?"hit":"not hit");
274 * Put back the conn and restart its timer with its timeout
276 void ip_vs_conn_put(struct ip_vs_conn *cp)
278 /* reset it expire in its timeout */
279 mod_timer(&cp->timer, jiffies+cp->timeout);
281 __ip_vs_conn_put(cp);
286 * Fill a no_client_port connection with a client port number
288 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __u16 cport)
290 if (ip_vs_conn_unhash(cp)) {
291 spin_lock(&cp->lock);
292 if (cp->flags & IP_VS_CONN_F_NO_CPORT) {
293 atomic_dec(&ip_vs_conn_no_cport_cnt);
294 cp->flags &= ~IP_VS_CONN_F_NO_CPORT;
297 spin_unlock(&cp->lock);
299 /* hash on new dport */
306 * Bind a connection entry with the corresponding packet_xmit.
307 * Called by ip_vs_conn_new.
309 static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp)
311 switch (IP_VS_FWD_METHOD(cp)) {
312 case IP_VS_CONN_F_MASQ:
313 cp->packet_xmit = ip_vs_nat_xmit;
316 case IP_VS_CONN_F_TUNNEL:
317 cp->packet_xmit = ip_vs_tunnel_xmit;
320 case IP_VS_CONN_F_DROUTE:
321 cp->packet_xmit = ip_vs_dr_xmit;
324 case IP_VS_CONN_F_LOCALNODE:
325 cp->packet_xmit = ip_vs_null_xmit;
328 case IP_VS_CONN_F_BYPASS:
329 cp->packet_xmit = ip_vs_bypass_xmit;
335 static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest)
337 return atomic_read(&dest->activeconns)
338 + atomic_read(&dest->inactconns);
342 * Bind a connection entry with a virtual service destination
343 * Called just after a new connection entry is created.
346 ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
348 /* if dest is NULL, then return directly */
352 /* Increase the refcnt counter of the dest */
353 atomic_inc(&dest->refcnt);
355 /* Bind with the destination and its corresponding transmitter */
356 cp->flags |= atomic_read(&dest->conn_flags);
359 IP_VS_DBG(9, "Bind-dest %s c:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d "
360 "d:%u.%u.%u.%u:%d fwd:%c s:%u flg:%X cnt:%d destcnt:%d\n",
361 ip_vs_proto_name(cp->protocol),
362 NIPQUAD(cp->caddr), ntohs(cp->cport),
363 NIPQUAD(cp->vaddr), ntohs(cp->vport),
364 NIPQUAD(cp->daddr), ntohs(cp->dport),
365 ip_vs_fwd_tag(cp), cp->state,
366 cp->flags, atomic_read(&cp->refcnt),
367 atomic_read(&dest->refcnt));
369 /* Update the connection counters */
370 if (cp->cport || (cp->flags & IP_VS_CONN_F_NO_CPORT)) {
371 /* It is a normal connection, so increase the inactive
372 connection counter because it is in TCP SYNRECV
373 state (inactive) or other protocol inacive state */
374 atomic_inc(&dest->inactconns);
376 /* It is a persistent connection/template, so increase
377 the peristent connection counter */
378 atomic_inc(&dest->persistconns);
381 if (dest->u_threshold != 0 &&
382 ip_vs_dest_totalconns(dest) >= dest->u_threshold)
383 dest->flags |= IP_VS_DEST_F_OVERLOAD;
388 * Unbind a connection entry with its VS destination
389 * Called by the ip_vs_conn_expire function.
391 static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
393 struct ip_vs_dest *dest = cp->dest;
398 IP_VS_DBG(9, "Unbind-dest %s c:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d "
399 "d:%u.%u.%u.%u:%d fwd:%c s:%u flg:%X cnt:%d destcnt:%d\n",
400 ip_vs_proto_name(cp->protocol),
401 NIPQUAD(cp->caddr), ntohs(cp->cport),
402 NIPQUAD(cp->vaddr), ntohs(cp->vport),
403 NIPQUAD(cp->daddr), ntohs(cp->dport),
404 ip_vs_fwd_tag(cp), cp->state,
405 cp->flags, atomic_read(&cp->refcnt),
406 atomic_read(&dest->refcnt));
408 /* Update the connection counters */
409 if (cp->cport || (cp->flags & IP_VS_CONN_F_NO_CPORT)) {
410 /* It is a normal connection, so decrease the inactconns
411 or activeconns counter */
412 if (cp->flags & IP_VS_CONN_F_INACTIVE) {
413 atomic_dec(&dest->inactconns);
415 atomic_dec(&dest->activeconns);
418 /* It is a persistent connection/template, so decrease
419 the peristent connection counter */
420 atomic_dec(&dest->persistconns);
423 if (dest->l_threshold != 0) {
424 if (ip_vs_dest_totalconns(dest) < dest->l_threshold)
425 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
426 } else if (dest->u_threshold != 0) {
427 if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3)
428 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
430 if (dest->flags & IP_VS_DEST_F_OVERLOAD)
431 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
435 * Simply decrease the refcnt of the dest, because the
436 * dest will be either in service's destination list
439 atomic_dec(&dest->refcnt);
444 * Checking if the destination of a connection template is available.
445 * If available, return 1, otherwise invalidate this connection
446 * template and return 0.
448 int ip_vs_check_template(struct ip_vs_conn *ct)
450 struct ip_vs_dest *dest = ct->dest;
453 * Checking the dest server status.
455 if ((dest == NULL) ||
456 !(dest->flags & IP_VS_DEST_F_AVAILABLE)) {
457 IP_VS_DBG(9, "check_template: dest not available for "
458 "protocol %s s:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d "
459 "-> d:%u.%u.%u.%u:%d\n",
460 ip_vs_proto_name(ct->protocol),
461 NIPQUAD(ct->caddr), ntohs(ct->cport),
462 NIPQUAD(ct->vaddr), ntohs(ct->vport),
463 NIPQUAD(ct->daddr), ntohs(ct->dport));
466 * Invalidate the connection template
469 if (ip_vs_conn_unhash(ct)) {
478 * Simply decrease the refcnt of the template,
479 * don't restart its timer.
481 atomic_dec(&ct->refcnt);
487 static void ip_vs_conn_expire(unsigned long data)
489 struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
496 atomic_inc(&cp->refcnt);
499 * do I control anybody?
501 if (atomic_read(&cp->n_control))
505 * unhash it if it is hashed in the conn table
507 if (!ip_vs_conn_unhash(cp))
511 * refcnt==1 implies I'm the only one referrer
513 if (likely(atomic_read(&cp->refcnt) == 1)) {
514 /* delete the timer if it is activated by other users */
515 if (timer_pending(&cp->timer))
516 del_timer(&cp->timer);
518 /* does anybody control me? */
520 ip_vs_control_del(cp);
522 if (unlikely(cp->app != NULL))
523 ip_vs_unbind_app(cp);
524 ip_vs_unbind_dest(cp);
525 if (cp->flags & IP_VS_CONN_F_NO_CPORT)
526 atomic_dec(&ip_vs_conn_no_cport_cnt);
527 atomic_dec(&ip_vs_conn_count);
529 kmem_cache_free(ip_vs_conn_cachep, cp);
533 /* hash it back to the table */
537 IP_VS_DBG(7, "delayed: refcnt-1=%d conn.n_control=%d\n",
538 atomic_read(&cp->refcnt)-1,
539 atomic_read(&cp->n_control));
545 void ip_vs_conn_expire_now(struct ip_vs_conn *cp)
547 if (del_timer(&cp->timer))
548 mod_timer(&cp->timer, jiffies);
549 __ip_vs_conn_put(cp);
554 * Create a new connection entry and hash it into the ip_vs_conn_tab
557 ip_vs_conn_new(int proto, __u32 caddr, __u16 cport, __u32 vaddr, __u16 vport,
558 __u32 daddr, __u16 dport, unsigned flags,
559 struct ip_vs_dest *dest)
561 struct ip_vs_conn *cp;
562 struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
564 cp = kmem_cache_alloc(ip_vs_conn_cachep, GFP_ATOMIC);
566 IP_VS_ERR_RL("ip_vs_conn_new: no memory available.\n");
570 memset(cp, 0, sizeof(*cp));
571 INIT_LIST_HEAD(&cp->c_list);
572 init_timer(&cp->timer);
573 cp->timer.data = (unsigned long)cp;
574 cp->timer.function = ip_vs_conn_expire;
575 cp->protocol = proto;
583 cp->lock = SPIN_LOCK_UNLOCKED;
586 * Set the entry is referenced by the current thread before hashing
587 * it in the table, so that other thread run ip_vs_random_dropentry
588 * but cannot drop this entry.
590 atomic_set(&cp->refcnt, 1);
592 atomic_set(&cp->n_control, 0);
593 atomic_set(&cp->in_pkts, 0);
595 atomic_inc(&ip_vs_conn_count);
596 if (flags & IP_VS_CONN_F_NO_CPORT)
597 atomic_inc(&ip_vs_conn_no_cport_cnt);
599 /* Bind the connection with a destination server */
600 ip_vs_bind_dest(cp, dest);
602 /* Set its state and timeout */
606 /* Bind its packet transmitter */
609 if (unlikely(pp && atomic_read(&pp->appcnt)))
610 ip_vs_bind_app(cp, pp);
612 /* Hash it in the ip_vs_conn_tab finally */
620 * /proc/net/ip_vs_conn entries
622 #ifdef CONFIG_PROC_FS
624 static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos)
627 struct ip_vs_conn *cp;
629 for(idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) {
630 ct_read_lock_bh(idx);
631 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
633 seq->private = &ip_vs_conn_tab[idx];
637 ct_read_unlock_bh(idx);
643 static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos)
646 return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN;
649 static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos)
651 struct ip_vs_conn *cp = v;
652 struct list_head *e, *l = seq->private;
656 if (v == SEQ_START_TOKEN)
657 return ip_vs_conn_array(seq, 0);
659 /* more on same hash chain? */
660 if ((e = cp->c_list.next) != l)
661 return list_entry(e, struct ip_vs_conn, c_list);
663 idx = l - ip_vs_conn_tab;
664 ct_read_unlock_bh(idx);
666 while (++idx < IP_VS_CONN_TAB_SIZE) {
667 ct_read_lock_bh(idx);
668 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
669 seq->private = &ip_vs_conn_tab[idx];
672 ct_read_unlock_bh(idx);
678 static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v)
680 struct list_head *l = seq->private;
683 ct_read_unlock_bh(l - ip_vs_conn_tab);
686 static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
689 if (v == SEQ_START_TOKEN)
691 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n");
693 const struct ip_vs_conn *cp = v;
696 "%-3s %08X %04X %08X %04X %08X %04X %-11s %7lu\n",
697 ip_vs_proto_name(cp->protocol),
698 ntohl(cp->caddr), ntohs(cp->cport),
699 ntohl(cp->vaddr), ntohs(cp->vport),
700 ntohl(cp->daddr), ntohs(cp->dport),
701 ip_vs_state_name(cp->protocol, cp->state),
702 (cp->timer.expires-jiffies)/HZ);
707 static struct seq_operations ip_vs_conn_seq_ops = {
708 .start = ip_vs_conn_seq_start,
709 .next = ip_vs_conn_seq_next,
710 .stop = ip_vs_conn_seq_stop,
711 .show = ip_vs_conn_seq_show,
714 static int ip_vs_conn_open(struct inode *inode, struct file *file)
716 return seq_open(file, &ip_vs_conn_seq_ops);
719 static struct file_operations ip_vs_conn_fops = {
720 .owner = THIS_MODULE,
721 .open = ip_vs_conn_open,
724 .release = seq_release,
730 * Randomly drop connection entries before running out of memory
732 static inline int todrop_entry(struct ip_vs_conn *cp)
735 * The drop rate array needs tuning for real environments.
736 * Called from timer bh only => no locking
738 static char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
739 static char todrop_counter[9] = {0};
742 /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
743 This will leave enough time for normal connection to get
745 if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ))
748 /* Don't drop the entry if its number of incoming packets is not
750 i = atomic_read(&cp->in_pkts);
751 if (i > 8 || i < 0) return 0;
753 if (!todrop_rate[i]) return 0;
754 if (--todrop_counter[i] > 0) return 0;
756 todrop_counter[i] = todrop_rate[i];
761 void ip_vs_random_dropentry(void)
764 struct ip_vs_conn *cp;
765 struct ip_vs_conn *ct;
768 * Randomly scan 1/32 of the whole table every second
770 for (idx = 0; idx < (IP_VS_CONN_TAB_SIZE>>5); idx++) {
771 unsigned hash = net_random() & IP_VS_CONN_TAB_MASK;
774 * Lock is actually needed in this loop.
778 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
779 if (!cp->cport && !(cp->flags & IP_VS_CONN_F_NO_CPORT))
780 /* connection template */
783 if (cp->protocol == IPPROTO_TCP) {
785 case IP_VS_TCP_S_SYN_RECV:
786 case IP_VS_TCP_S_SYNACK:
789 case IP_VS_TCP_S_ESTABLISHED:
790 if (todrop_entry(cp))
798 if (!todrop_entry(cp))
803 * Drop the entry, and drop its ct if not referenced
805 atomic_inc(&cp->refcnt);
806 ct_write_unlock(hash);
808 if ((ct = cp->control))
809 atomic_inc(&ct->refcnt);
810 IP_VS_DBG(4, "del connection\n");
811 ip_vs_conn_expire_now(cp);
813 IP_VS_DBG(4, "del conn template\n");
814 ip_vs_conn_expire_now(ct);
818 ct_write_unlock(hash);
824 * Flush all the connection entries in the ip_vs_conn_tab
826 static void ip_vs_conn_flush(void)
829 struct ip_vs_conn *cp;
830 struct ip_vs_conn *ct;
833 for (idx=0; idx<IP_VS_CONN_TAB_SIZE; idx++) {
835 * Lock is actually needed in this loop.
837 ct_write_lock_bh(idx);
839 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
840 atomic_inc(&cp->refcnt);
841 ct_write_unlock(idx);
843 if ((ct = cp->control))
844 atomic_inc(&ct->refcnt);
845 IP_VS_DBG(4, "del connection\n");
846 ip_vs_conn_expire_now(cp);
848 IP_VS_DBG(4, "del conn template\n");
849 ip_vs_conn_expire_now(ct);
853 ct_write_unlock_bh(idx);
856 /* the counter may be not NULL, because maybe some conn entries
857 are run by slow timer handler or unhashed but still referred */
858 if (atomic_read(&ip_vs_conn_count) != 0) {
865 int ip_vs_conn_init(void)
870 * Allocate the connection hash table and initialize its list heads
872 ip_vs_conn_tab = vmalloc(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head));
876 /* Allocate ip_vs_conn slab cache */
877 ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn",
878 sizeof(struct ip_vs_conn), 0,
879 SLAB_HWCACHE_ALIGN, NULL, NULL);
880 if (!ip_vs_conn_cachep) {
881 vfree(ip_vs_conn_tab);
885 IP_VS_INFO("Connection hash table configured "
886 "(size=%d, memory=%ldKbytes)\n",
888 (long)(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head))/1024);
889 IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
890 sizeof(struct ip_vs_conn));
892 for (idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) {
893 INIT_LIST_HEAD(&ip_vs_conn_tab[idx]);
896 for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) {
897 __ip_vs_conntbl_lock_array[idx].l = RW_LOCK_UNLOCKED;
900 proc_net_fops_create("ip_vs_conn", 0, &ip_vs_conn_fops);
902 /* calculate the random value for connection hash */
903 get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
909 void ip_vs_conn_cleanup(void)
911 /* flush all the connection entries first */
914 /* Release the empty cache */
915 kmem_cache_destroy(ip_vs_conn_cachep);
916 proc_net_remove("ip_vs_conn");
917 vfree(ip_vs_conn_tab);