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 * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
9 * Peter Kese <peter.kese@ijs.si>
10 * Julian Anastasov <ja@ssi.bg>
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
17 * The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
18 * with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
19 * and others. Many code here is taken from IP MASQ code of kernel 2.2.
25 #define KMSG_COMPONENT "IPVS"
26 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
28 #include <linux/interrupt.h>
30 #include <linux/net.h>
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/vmalloc.h>
34 #include <linux/proc_fs.h> /* for proc_net_* */
35 #include <linux/slab.h>
36 #include <linux/seq_file.h>
37 #include <linux/jhash.h>
38 #include <linux/random.h>
40 #include <net/net_namespace.h>
41 #include <net/ip_vs.h>
44 #ifndef CONFIG_IP_VS_TAB_BITS
45 #define CONFIG_IP_VS_TAB_BITS 12
49 * Connection hash size. Default is what was selected at compile time.
51 int ip_vs_conn_tab_bits
= CONFIG_IP_VS_TAB_BITS
;
52 module_param_named(conn_tab_bits
, ip_vs_conn_tab_bits
, int, 0444);
53 MODULE_PARM_DESC(conn_tab_bits
, "Set connections' hash size");
55 /* size and mask values */
56 int ip_vs_conn_tab_size
;
57 int ip_vs_conn_tab_mask
;
60 * Connection hash table: for input and output packets lookups of IPVS
62 static struct list_head
*ip_vs_conn_tab
;
64 /* SLAB cache for IPVS connections */
65 static struct kmem_cache
*ip_vs_conn_cachep __read_mostly
;
67 /* counter for current IPVS connections */
68 static atomic_t ip_vs_conn_count
= ATOMIC_INIT(0);
70 /* counter for no client port connections */
71 static atomic_t ip_vs_conn_no_cport_cnt
= ATOMIC_INIT(0);
73 /* random value for IPVS connection hash */
74 static unsigned int ip_vs_conn_rnd
;
77 * Fine locking granularity for big connection hash table
79 #define CT_LOCKARRAY_BITS 4
80 #define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS)
81 #define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1)
83 struct ip_vs_aligned_lock
86 } __attribute__((__aligned__(SMP_CACHE_BYTES
)));
88 /* lock array for conn table */
89 static struct ip_vs_aligned_lock
90 __ip_vs_conntbl_lock_array
[CT_LOCKARRAY_SIZE
] __cacheline_aligned
;
92 static inline void ct_read_lock(unsigned key
)
94 read_lock(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
97 static inline void ct_read_unlock(unsigned key
)
99 read_unlock(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
102 static inline void ct_write_lock(unsigned key
)
104 write_lock(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
107 static inline void ct_write_unlock(unsigned key
)
109 write_unlock(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
112 static inline void ct_read_lock_bh(unsigned key
)
114 read_lock_bh(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
117 static inline void ct_read_unlock_bh(unsigned key
)
119 read_unlock_bh(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
122 static inline void ct_write_lock_bh(unsigned key
)
124 write_lock_bh(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
127 static inline void ct_write_unlock_bh(unsigned key
)
129 write_unlock_bh(&__ip_vs_conntbl_lock_array
[key
&CT_LOCKARRAY_MASK
].l
);
134 * Returns hash value for IPVS connection entry
136 static unsigned int ip_vs_conn_hashkey(int af
, unsigned proto
,
137 const union nf_inet_addr
*addr
,
140 #ifdef CONFIG_IP_VS_IPV6
142 return jhash_3words(jhash(addr
, 16, ip_vs_conn_rnd
),
143 (__force u32
)port
, proto
, ip_vs_conn_rnd
)
144 & ip_vs_conn_tab_mask
;
146 return jhash_3words((__force u32
)addr
->ip
, (__force u32
)port
, proto
,
148 & ip_vs_conn_tab_mask
;
153 * Hashes ip_vs_conn in ip_vs_conn_tab by proto,addr,port.
154 * returns bool success.
156 static inline int ip_vs_conn_hash(struct ip_vs_conn
*cp
)
161 if (cp
->flags
& IP_VS_CONN_F_ONE_PACKET
)
164 /* Hash by protocol, client address and port */
165 hash
= ip_vs_conn_hashkey(cp
->af
, cp
->protocol
, &cp
->caddr
, cp
->cport
);
169 if (!(cp
->flags
& IP_VS_CONN_F_HASHED
)) {
170 list_add(&cp
->c_list
, &ip_vs_conn_tab
[hash
]);
171 cp
->flags
|= IP_VS_CONN_F_HASHED
;
172 atomic_inc(&cp
->refcnt
);
175 pr_err("%s(): request for already hashed, called from %pF\n",
176 __func__
, __builtin_return_address(0));
180 ct_write_unlock(hash
);
187 * UNhashes ip_vs_conn from ip_vs_conn_tab.
188 * returns bool success.
190 static inline int ip_vs_conn_unhash(struct ip_vs_conn
*cp
)
195 /* unhash it and decrease its reference counter */
196 hash
= ip_vs_conn_hashkey(cp
->af
, cp
->protocol
, &cp
->caddr
, cp
->cport
);
200 if (cp
->flags
& IP_VS_CONN_F_HASHED
) {
201 list_del(&cp
->c_list
);
202 cp
->flags
&= ~IP_VS_CONN_F_HASHED
;
203 atomic_dec(&cp
->refcnt
);
208 ct_write_unlock(hash
);
215 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
216 * Called for pkts coming from OUTside-to-INside.
217 * s_addr, s_port: pkt source address (foreign host)
218 * d_addr, d_port: pkt dest address (load balancer)
220 static inline struct ip_vs_conn
*__ip_vs_conn_in_get
221 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
222 const union nf_inet_addr
*d_addr
, __be16 d_port
)
225 struct ip_vs_conn
*cp
;
227 hash
= ip_vs_conn_hashkey(af
, protocol
, s_addr
, s_port
);
231 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
233 ip_vs_addr_equal(af
, s_addr
, &cp
->caddr
) &&
234 ip_vs_addr_equal(af
, d_addr
, &cp
->vaddr
) &&
235 s_port
== cp
->cport
&& d_port
== cp
->vport
&&
236 ((!s_port
) ^ (!(cp
->flags
& IP_VS_CONN_F_NO_CPORT
))) &&
237 protocol
== cp
->protocol
) {
239 atomic_inc(&cp
->refcnt
);
240 ct_read_unlock(hash
);
245 ct_read_unlock(hash
);
250 struct ip_vs_conn
*ip_vs_conn_in_get
251 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
252 const union nf_inet_addr
*d_addr
, __be16 d_port
)
254 struct ip_vs_conn
*cp
;
256 cp
= __ip_vs_conn_in_get(af
, protocol
, s_addr
, s_port
, d_addr
, d_port
);
257 if (!cp
&& atomic_read(&ip_vs_conn_no_cport_cnt
))
258 cp
= __ip_vs_conn_in_get(af
, protocol
, s_addr
, 0, d_addr
,
261 IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n",
262 ip_vs_proto_name(protocol
),
263 IP_VS_DBG_ADDR(af
, s_addr
), ntohs(s_port
),
264 IP_VS_DBG_ADDR(af
, d_addr
), ntohs(d_port
),
265 cp
? "hit" : "not hit");
270 /* Get reference to connection template */
271 struct ip_vs_conn
*ip_vs_ct_in_get
272 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
273 const union nf_inet_addr
*d_addr
, __be16 d_port
)
276 struct ip_vs_conn
*cp
;
278 hash
= ip_vs_conn_hashkey(af
, protocol
, s_addr
, s_port
);
282 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
284 ip_vs_addr_equal(af
, s_addr
, &cp
->caddr
) &&
285 /* protocol should only be IPPROTO_IP if
286 * d_addr is a fwmark */
287 ip_vs_addr_equal(protocol
== IPPROTO_IP
? AF_UNSPEC
: af
,
288 d_addr
, &cp
->vaddr
) &&
289 s_port
== cp
->cport
&& d_port
== cp
->vport
&&
290 cp
->flags
& IP_VS_CONN_F_TEMPLATE
&&
291 protocol
== cp
->protocol
) {
293 atomic_inc(&cp
->refcnt
);
300 ct_read_unlock(hash
);
302 IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n",
303 ip_vs_proto_name(protocol
),
304 IP_VS_DBG_ADDR(af
, s_addr
), ntohs(s_port
),
305 IP_VS_DBG_ADDR(af
, d_addr
), ntohs(d_port
),
306 cp
? "hit" : "not hit");
312 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
313 * Called for pkts coming from inside-to-OUTside.
314 * s_addr, s_port: pkt source address (inside host)
315 * d_addr, d_port: pkt dest address (foreign host)
317 struct ip_vs_conn
*ip_vs_conn_out_get
318 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
319 const union nf_inet_addr
*d_addr
, __be16 d_port
)
322 struct ip_vs_conn
*cp
, *ret
=NULL
;
325 * Check for "full" addressed entries
327 hash
= ip_vs_conn_hashkey(af
, protocol
, d_addr
, d_port
);
331 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
333 ip_vs_addr_equal(af
, d_addr
, &cp
->caddr
) &&
334 ip_vs_addr_equal(af
, s_addr
, &cp
->daddr
) &&
335 d_port
== cp
->cport
&& s_port
== cp
->dport
&&
336 protocol
== cp
->protocol
) {
338 atomic_inc(&cp
->refcnt
);
344 ct_read_unlock(hash
);
346 IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n",
347 ip_vs_proto_name(protocol
),
348 IP_VS_DBG_ADDR(af
, s_addr
), ntohs(s_port
),
349 IP_VS_DBG_ADDR(af
, d_addr
), ntohs(d_port
),
350 ret
? "hit" : "not hit");
357 * Put back the conn and restart its timer with its timeout
359 void ip_vs_conn_put(struct ip_vs_conn
*cp
)
361 unsigned long t
= (cp
->flags
& IP_VS_CONN_F_ONE_PACKET
) ?
363 mod_timer(&cp
->timer
, jiffies
+t
);
365 __ip_vs_conn_put(cp
);
370 * Fill a no_client_port connection with a client port number
372 void ip_vs_conn_fill_cport(struct ip_vs_conn
*cp
, __be16 cport
)
374 if (ip_vs_conn_unhash(cp
)) {
375 spin_lock(&cp
->lock
);
376 if (cp
->flags
& IP_VS_CONN_F_NO_CPORT
) {
377 atomic_dec(&ip_vs_conn_no_cport_cnt
);
378 cp
->flags
&= ~IP_VS_CONN_F_NO_CPORT
;
381 spin_unlock(&cp
->lock
);
383 /* hash on new dport */
390 * Bind a connection entry with the corresponding packet_xmit.
391 * Called by ip_vs_conn_new.
393 static inline void ip_vs_bind_xmit(struct ip_vs_conn
*cp
)
395 switch (IP_VS_FWD_METHOD(cp
)) {
396 case IP_VS_CONN_F_MASQ
:
397 cp
->packet_xmit
= ip_vs_nat_xmit
;
400 case IP_VS_CONN_F_TUNNEL
:
401 cp
->packet_xmit
= ip_vs_tunnel_xmit
;
404 case IP_VS_CONN_F_DROUTE
:
405 cp
->packet_xmit
= ip_vs_dr_xmit
;
408 case IP_VS_CONN_F_LOCALNODE
:
409 cp
->packet_xmit
= ip_vs_null_xmit
;
412 case IP_VS_CONN_F_BYPASS
:
413 cp
->packet_xmit
= ip_vs_bypass_xmit
;
418 #ifdef CONFIG_IP_VS_IPV6
419 static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn
*cp
)
421 switch (IP_VS_FWD_METHOD(cp
)) {
422 case IP_VS_CONN_F_MASQ
:
423 cp
->packet_xmit
= ip_vs_nat_xmit_v6
;
426 case IP_VS_CONN_F_TUNNEL
:
427 cp
->packet_xmit
= ip_vs_tunnel_xmit_v6
;
430 case IP_VS_CONN_F_DROUTE
:
431 cp
->packet_xmit
= ip_vs_dr_xmit_v6
;
434 case IP_VS_CONN_F_LOCALNODE
:
435 cp
->packet_xmit
= ip_vs_null_xmit
;
438 case IP_VS_CONN_F_BYPASS
:
439 cp
->packet_xmit
= ip_vs_bypass_xmit_v6
;
446 static inline int ip_vs_dest_totalconns(struct ip_vs_dest
*dest
)
448 return atomic_read(&dest
->activeconns
)
449 + atomic_read(&dest
->inactconns
);
453 * Bind a connection entry with a virtual service destination
454 * Called just after a new connection entry is created.
457 ip_vs_bind_dest(struct ip_vs_conn
*cp
, struct ip_vs_dest
*dest
)
459 /* if dest is NULL, then return directly */
463 /* Increase the refcnt counter of the dest */
464 atomic_inc(&dest
->refcnt
);
466 /* Bind with the destination and its corresponding transmitter */
467 if ((cp
->flags
& IP_VS_CONN_F_SYNC
) &&
468 (!(cp
->flags
& IP_VS_CONN_F_TEMPLATE
)))
469 /* if the connection is not template and is created
470 * by sync, preserve the activity flag.
472 cp
->flags
|= atomic_read(&dest
->conn_flags
) &
473 (~IP_VS_CONN_F_INACTIVE
);
475 cp
->flags
|= atomic_read(&dest
->conn_flags
);
478 IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
479 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
481 ip_vs_proto_name(cp
->protocol
),
482 IP_VS_DBG_ADDR(cp
->af
, &cp
->caddr
), ntohs(cp
->cport
),
483 IP_VS_DBG_ADDR(cp
->af
, &cp
->vaddr
), ntohs(cp
->vport
),
484 IP_VS_DBG_ADDR(cp
->af
, &cp
->daddr
), ntohs(cp
->dport
),
485 ip_vs_fwd_tag(cp
), cp
->state
,
486 cp
->flags
, atomic_read(&cp
->refcnt
),
487 atomic_read(&dest
->refcnt
));
489 /* Update the connection counters */
490 if (!(cp
->flags
& IP_VS_CONN_F_TEMPLATE
)) {
491 /* It is a normal connection, so increase the inactive
492 connection counter because it is in TCP SYNRECV
493 state (inactive) or other protocol inacive state */
494 if ((cp
->flags
& IP_VS_CONN_F_SYNC
) &&
495 (!(cp
->flags
& IP_VS_CONN_F_INACTIVE
)))
496 atomic_inc(&dest
->activeconns
);
498 atomic_inc(&dest
->inactconns
);
500 /* It is a persistent connection/template, so increase
501 the peristent connection counter */
502 atomic_inc(&dest
->persistconns
);
505 if (dest
->u_threshold
!= 0 &&
506 ip_vs_dest_totalconns(dest
) >= dest
->u_threshold
)
507 dest
->flags
|= IP_VS_DEST_F_OVERLOAD
;
512 * Check if there is a destination for the connection, if so
513 * bind the connection to the destination.
515 struct ip_vs_dest
*ip_vs_try_bind_dest(struct ip_vs_conn
*cp
)
517 struct ip_vs_dest
*dest
;
519 if ((cp
) && (!cp
->dest
)) {
520 dest
= ip_vs_find_dest(cp
->af
, &cp
->daddr
, cp
->dport
,
521 &cp
->vaddr
, cp
->vport
,
523 ip_vs_bind_dest(cp
, dest
);
531 * Unbind a connection entry with its VS destination
532 * Called by the ip_vs_conn_expire function.
534 static inline void ip_vs_unbind_dest(struct ip_vs_conn
*cp
)
536 struct ip_vs_dest
*dest
= cp
->dest
;
541 IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d "
542 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
544 ip_vs_proto_name(cp
->protocol
),
545 IP_VS_DBG_ADDR(cp
->af
, &cp
->caddr
), ntohs(cp
->cport
),
546 IP_VS_DBG_ADDR(cp
->af
, &cp
->vaddr
), ntohs(cp
->vport
),
547 IP_VS_DBG_ADDR(cp
->af
, &cp
->daddr
), ntohs(cp
->dport
),
548 ip_vs_fwd_tag(cp
), cp
->state
,
549 cp
->flags
, atomic_read(&cp
->refcnt
),
550 atomic_read(&dest
->refcnt
));
552 /* Update the connection counters */
553 if (!(cp
->flags
& IP_VS_CONN_F_TEMPLATE
)) {
554 /* It is a normal connection, so decrease the inactconns
555 or activeconns counter */
556 if (cp
->flags
& IP_VS_CONN_F_INACTIVE
) {
557 atomic_dec(&dest
->inactconns
);
559 atomic_dec(&dest
->activeconns
);
562 /* It is a persistent connection/template, so decrease
563 the peristent connection counter */
564 atomic_dec(&dest
->persistconns
);
567 if (dest
->l_threshold
!= 0) {
568 if (ip_vs_dest_totalconns(dest
) < dest
->l_threshold
)
569 dest
->flags
&= ~IP_VS_DEST_F_OVERLOAD
;
570 } else if (dest
->u_threshold
!= 0) {
571 if (ip_vs_dest_totalconns(dest
) * 4 < dest
->u_threshold
* 3)
572 dest
->flags
&= ~IP_VS_DEST_F_OVERLOAD
;
574 if (dest
->flags
& IP_VS_DEST_F_OVERLOAD
)
575 dest
->flags
&= ~IP_VS_DEST_F_OVERLOAD
;
579 * Simply decrease the refcnt of the dest, because the
580 * dest will be either in service's destination list
583 atomic_dec(&dest
->refcnt
);
588 * Checking if the destination of a connection template is available.
589 * If available, return 1, otherwise invalidate this connection
590 * template and return 0.
592 int ip_vs_check_template(struct ip_vs_conn
*ct
)
594 struct ip_vs_dest
*dest
= ct
->dest
;
597 * Checking the dest server status.
599 if ((dest
== NULL
) ||
600 !(dest
->flags
& IP_VS_DEST_F_AVAILABLE
) ||
601 (sysctl_ip_vs_expire_quiescent_template
&&
602 (atomic_read(&dest
->weight
) == 0))) {
603 IP_VS_DBG_BUF(9, "check_template: dest not available for "
604 "protocol %s s:%s:%d v:%s:%d "
606 ip_vs_proto_name(ct
->protocol
),
607 IP_VS_DBG_ADDR(ct
->af
, &ct
->caddr
),
609 IP_VS_DBG_ADDR(ct
->af
, &ct
->vaddr
),
611 IP_VS_DBG_ADDR(ct
->af
, &ct
->daddr
),
615 * Invalidate the connection template
617 if (ct
->vport
!= htons(0xffff)) {
618 if (ip_vs_conn_unhash(ct
)) {
619 ct
->dport
= htons(0xffff);
620 ct
->vport
= htons(0xffff);
627 * Simply decrease the refcnt of the template,
628 * don't restart its timer.
630 atomic_dec(&ct
->refcnt
);
636 static void ip_vs_conn_expire(unsigned long data
)
638 struct ip_vs_conn
*cp
= (struct ip_vs_conn
*)data
;
645 atomic_inc(&cp
->refcnt
);
648 * do I control anybody?
650 if (atomic_read(&cp
->n_control
))
654 * unhash it if it is hashed in the conn table
656 if (!ip_vs_conn_unhash(cp
) && !(cp
->flags
& IP_VS_CONN_F_ONE_PACKET
))
660 * refcnt==1 implies I'm the only one referrer
662 if (likely(atomic_read(&cp
->refcnt
) == 1)) {
663 /* delete the timer if it is activated by other users */
664 if (timer_pending(&cp
->timer
))
665 del_timer(&cp
->timer
);
667 /* does anybody control me? */
669 ip_vs_control_del(cp
);
671 if (unlikely(cp
->app
!= NULL
))
672 ip_vs_unbind_app(cp
);
673 ip_vs_unbind_dest(cp
);
674 if (cp
->flags
& IP_VS_CONN_F_NO_CPORT
)
675 atomic_dec(&ip_vs_conn_no_cport_cnt
);
676 atomic_dec(&ip_vs_conn_count
);
678 kmem_cache_free(ip_vs_conn_cachep
, cp
);
682 /* hash it back to the table */
686 IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n",
687 atomic_read(&cp
->refcnt
)-1,
688 atomic_read(&cp
->n_control
));
694 void ip_vs_conn_expire_now(struct ip_vs_conn
*cp
)
696 if (del_timer(&cp
->timer
))
697 mod_timer(&cp
->timer
, jiffies
);
702 * Create a new connection entry and hash it into the ip_vs_conn_tab
705 ip_vs_conn_new(int af
, int proto
, const union nf_inet_addr
*caddr
, __be16 cport
,
706 const union nf_inet_addr
*vaddr
, __be16 vport
,
707 const union nf_inet_addr
*daddr
, __be16 dport
, unsigned flags
,
708 struct ip_vs_dest
*dest
)
710 struct ip_vs_conn
*cp
;
711 struct ip_vs_protocol
*pp
= ip_vs_proto_get(proto
);
713 cp
= kmem_cache_zalloc(ip_vs_conn_cachep
, GFP_ATOMIC
);
715 IP_VS_ERR_RL("%s(): no memory\n", __func__
);
719 INIT_LIST_HEAD(&cp
->c_list
);
720 setup_timer(&cp
->timer
, ip_vs_conn_expire
, (unsigned long)cp
);
722 cp
->protocol
= proto
;
723 ip_vs_addr_copy(af
, &cp
->caddr
, caddr
);
725 ip_vs_addr_copy(af
, &cp
->vaddr
, vaddr
);
727 /* proto should only be IPPROTO_IP if d_addr is a fwmark */
728 ip_vs_addr_copy(proto
== IPPROTO_IP
? AF_UNSPEC
: af
,
732 spin_lock_init(&cp
->lock
);
735 * Set the entry is referenced by the current thread before hashing
736 * it in the table, so that other thread run ip_vs_random_dropentry
737 * but cannot drop this entry.
739 atomic_set(&cp
->refcnt
, 1);
741 atomic_set(&cp
->n_control
, 0);
742 atomic_set(&cp
->in_pkts
, 0);
744 atomic_inc(&ip_vs_conn_count
);
745 if (flags
& IP_VS_CONN_F_NO_CPORT
)
746 atomic_inc(&ip_vs_conn_no_cport_cnt
);
748 /* Bind the connection with a destination server */
749 ip_vs_bind_dest(cp
, dest
);
751 /* Set its state and timeout */
755 /* Bind its packet transmitter */
756 #ifdef CONFIG_IP_VS_IPV6
758 ip_vs_bind_xmit_v6(cp
);
763 if (unlikely(pp
&& atomic_read(&pp
->appcnt
)))
764 ip_vs_bind_app(cp
, pp
);
766 /* Hash it in the ip_vs_conn_tab finally */
774 * /proc/net/ip_vs_conn entries
776 #ifdef CONFIG_PROC_FS
778 static void *ip_vs_conn_array(struct seq_file
*seq
, loff_t pos
)
781 struct ip_vs_conn
*cp
;
783 for (idx
= 0; idx
< ip_vs_conn_tab_size
; idx
++) {
784 ct_read_lock_bh(idx
);
785 list_for_each_entry(cp
, &ip_vs_conn_tab
[idx
], c_list
) {
787 seq
->private = &ip_vs_conn_tab
[idx
];
791 ct_read_unlock_bh(idx
);
797 static void *ip_vs_conn_seq_start(struct seq_file
*seq
, loff_t
*pos
)
800 return *pos
? ip_vs_conn_array(seq
, *pos
- 1) :SEQ_START_TOKEN
;
803 static void *ip_vs_conn_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
805 struct ip_vs_conn
*cp
= v
;
806 struct list_head
*e
, *l
= seq
->private;
810 if (v
== SEQ_START_TOKEN
)
811 return ip_vs_conn_array(seq
, 0);
813 /* more on same hash chain? */
814 if ((e
= cp
->c_list
.next
) != l
)
815 return list_entry(e
, struct ip_vs_conn
, c_list
);
817 idx
= l
- ip_vs_conn_tab
;
818 ct_read_unlock_bh(idx
);
820 while (++idx
< ip_vs_conn_tab_size
) {
821 ct_read_lock_bh(idx
);
822 list_for_each_entry(cp
, &ip_vs_conn_tab
[idx
], c_list
) {
823 seq
->private = &ip_vs_conn_tab
[idx
];
826 ct_read_unlock_bh(idx
);
832 static void ip_vs_conn_seq_stop(struct seq_file
*seq
, void *v
)
834 struct list_head
*l
= seq
->private;
837 ct_read_unlock_bh(l
- ip_vs_conn_tab
);
840 static int ip_vs_conn_seq_show(struct seq_file
*seq
, void *v
)
843 if (v
== SEQ_START_TOKEN
)
845 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n");
847 const struct ip_vs_conn
*cp
= v
;
849 #ifdef CONFIG_IP_VS_IPV6
850 if (cp
->af
== AF_INET6
)
851 seq_printf(seq
, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %7lu\n",
852 ip_vs_proto_name(cp
->protocol
),
853 &cp
->caddr
.in6
, ntohs(cp
->cport
),
854 &cp
->vaddr
.in6
, ntohs(cp
->vport
),
855 &cp
->daddr
.in6
, ntohs(cp
->dport
),
856 ip_vs_state_name(cp
->protocol
, cp
->state
),
857 (cp
->timer
.expires
-jiffies
)/HZ
);
861 "%-3s %08X %04X %08X %04X"
862 " %08X %04X %-11s %7lu\n",
863 ip_vs_proto_name(cp
->protocol
),
864 ntohl(cp
->caddr
.ip
), ntohs(cp
->cport
),
865 ntohl(cp
->vaddr
.ip
), ntohs(cp
->vport
),
866 ntohl(cp
->daddr
.ip
), ntohs(cp
->dport
),
867 ip_vs_state_name(cp
->protocol
, cp
->state
),
868 (cp
->timer
.expires
-jiffies
)/HZ
);
873 static const struct seq_operations ip_vs_conn_seq_ops
= {
874 .start
= ip_vs_conn_seq_start
,
875 .next
= ip_vs_conn_seq_next
,
876 .stop
= ip_vs_conn_seq_stop
,
877 .show
= ip_vs_conn_seq_show
,
880 static int ip_vs_conn_open(struct inode
*inode
, struct file
*file
)
882 return seq_open(file
, &ip_vs_conn_seq_ops
);
885 static const struct file_operations ip_vs_conn_fops
= {
886 .owner
= THIS_MODULE
,
887 .open
= ip_vs_conn_open
,
890 .release
= seq_release
,
893 static const char *ip_vs_origin_name(unsigned flags
)
895 if (flags
& IP_VS_CONN_F_SYNC
)
901 static int ip_vs_conn_sync_seq_show(struct seq_file
*seq
, void *v
)
904 if (v
== SEQ_START_TOKEN
)
906 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Origin Expires\n");
908 const struct ip_vs_conn
*cp
= v
;
910 #ifdef CONFIG_IP_VS_IPV6
911 if (cp
->af
== AF_INET6
)
912 seq_printf(seq
, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %-6s %7lu\n",
913 ip_vs_proto_name(cp
->protocol
),
914 &cp
->caddr
.in6
, ntohs(cp
->cport
),
915 &cp
->vaddr
.in6
, ntohs(cp
->vport
),
916 &cp
->daddr
.in6
, ntohs(cp
->dport
),
917 ip_vs_state_name(cp
->protocol
, cp
->state
),
918 ip_vs_origin_name(cp
->flags
),
919 (cp
->timer
.expires
-jiffies
)/HZ
);
923 "%-3s %08X %04X %08X %04X "
924 "%08X %04X %-11s %-6s %7lu\n",
925 ip_vs_proto_name(cp
->protocol
),
926 ntohl(cp
->caddr
.ip
), ntohs(cp
->cport
),
927 ntohl(cp
->vaddr
.ip
), ntohs(cp
->vport
),
928 ntohl(cp
->daddr
.ip
), ntohs(cp
->dport
),
929 ip_vs_state_name(cp
->protocol
, cp
->state
),
930 ip_vs_origin_name(cp
->flags
),
931 (cp
->timer
.expires
-jiffies
)/HZ
);
936 static const struct seq_operations ip_vs_conn_sync_seq_ops
= {
937 .start
= ip_vs_conn_seq_start
,
938 .next
= ip_vs_conn_seq_next
,
939 .stop
= ip_vs_conn_seq_stop
,
940 .show
= ip_vs_conn_sync_seq_show
,
943 static int ip_vs_conn_sync_open(struct inode
*inode
, struct file
*file
)
945 return seq_open(file
, &ip_vs_conn_sync_seq_ops
);
948 static const struct file_operations ip_vs_conn_sync_fops
= {
949 .owner
= THIS_MODULE
,
950 .open
= ip_vs_conn_sync_open
,
953 .release
= seq_release
,
960 * Randomly drop connection entries before running out of memory
962 static inline int todrop_entry(struct ip_vs_conn
*cp
)
965 * The drop rate array needs tuning for real environments.
966 * Called from timer bh only => no locking
968 static const char todrop_rate
[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
969 static char todrop_counter
[9] = {0};
972 /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
973 This will leave enough time for normal connection to get
975 if (time_before(cp
->timeout
+ jiffies
, cp
->timer
.expires
+ 60*HZ
))
978 /* Don't drop the entry if its number of incoming packets is not
980 i
= atomic_read(&cp
->in_pkts
);
981 if (i
> 8 || i
< 0) return 0;
983 if (!todrop_rate
[i
]) return 0;
984 if (--todrop_counter
[i
] > 0) return 0;
986 todrop_counter
[i
] = todrop_rate
[i
];
990 /* Called from keventd and must protect itself from softirqs */
991 void ip_vs_random_dropentry(void)
994 struct ip_vs_conn
*cp
;
997 * Randomly scan 1/32 of the whole table every second
999 for (idx
= 0; idx
< (ip_vs_conn_tab_size
>>5); idx
++) {
1000 unsigned hash
= net_random() & ip_vs_conn_tab_mask
;
1003 * Lock is actually needed in this loop.
1005 ct_write_lock_bh(hash
);
1007 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
1008 if (cp
->flags
& IP_VS_CONN_F_TEMPLATE
)
1009 /* connection template */
1012 if (cp
->protocol
== IPPROTO_TCP
) {
1014 case IP_VS_TCP_S_SYN_RECV
:
1015 case IP_VS_TCP_S_SYNACK
:
1018 case IP_VS_TCP_S_ESTABLISHED
:
1019 if (todrop_entry(cp
))
1027 if (!todrop_entry(cp
))
1031 IP_VS_DBG(4, "del connection\n");
1032 ip_vs_conn_expire_now(cp
);
1034 IP_VS_DBG(4, "del conn template\n");
1035 ip_vs_conn_expire_now(cp
->control
);
1038 ct_write_unlock_bh(hash
);
1044 * Flush all the connection entries in the ip_vs_conn_tab
1046 static void ip_vs_conn_flush(void)
1049 struct ip_vs_conn
*cp
;
1052 for (idx
= 0; idx
< ip_vs_conn_tab_size
; idx
++) {
1054 * Lock is actually needed in this loop.
1056 ct_write_lock_bh(idx
);
1058 list_for_each_entry(cp
, &ip_vs_conn_tab
[idx
], c_list
) {
1060 IP_VS_DBG(4, "del connection\n");
1061 ip_vs_conn_expire_now(cp
);
1063 IP_VS_DBG(4, "del conn template\n");
1064 ip_vs_conn_expire_now(cp
->control
);
1067 ct_write_unlock_bh(idx
);
1070 /* the counter may be not NULL, because maybe some conn entries
1071 are run by slow timer handler or unhashed but still referred */
1072 if (atomic_read(&ip_vs_conn_count
) != 0) {
1079 int __init
ip_vs_conn_init(void)
1083 /* Compute size and mask */
1084 ip_vs_conn_tab_size
= 1 << ip_vs_conn_tab_bits
;
1085 ip_vs_conn_tab_mask
= ip_vs_conn_tab_size
- 1;
1088 * Allocate the connection hash table and initialize its list heads
1090 ip_vs_conn_tab
= vmalloc(ip_vs_conn_tab_size
*
1091 sizeof(struct list_head
));
1092 if (!ip_vs_conn_tab
)
1095 /* Allocate ip_vs_conn slab cache */
1096 ip_vs_conn_cachep
= kmem_cache_create("ip_vs_conn",
1097 sizeof(struct ip_vs_conn
), 0,
1098 SLAB_HWCACHE_ALIGN
, NULL
);
1099 if (!ip_vs_conn_cachep
) {
1100 vfree(ip_vs_conn_tab
);
1104 pr_info("Connection hash table configured "
1105 "(size=%d, memory=%ldKbytes)\n",
1106 ip_vs_conn_tab_size
,
1107 (long)(ip_vs_conn_tab_size
*sizeof(struct list_head
))/1024);
1108 IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
1109 sizeof(struct ip_vs_conn
));
1111 for (idx
= 0; idx
< ip_vs_conn_tab_size
; idx
++) {
1112 INIT_LIST_HEAD(&ip_vs_conn_tab
[idx
]);
1115 for (idx
= 0; idx
< CT_LOCKARRAY_SIZE
; idx
++) {
1116 rwlock_init(&__ip_vs_conntbl_lock_array
[idx
].l
);
1119 proc_net_fops_create(&init_net
, "ip_vs_conn", 0, &ip_vs_conn_fops
);
1120 proc_net_fops_create(&init_net
, "ip_vs_conn_sync", 0, &ip_vs_conn_sync_fops
);
1122 /* calculate the random value for connection hash */
1123 get_random_bytes(&ip_vs_conn_rnd
, sizeof(ip_vs_conn_rnd
));
1129 void ip_vs_conn_cleanup(void)
1131 /* flush all the connection entries first */
1134 /* Release the empty cache */
1135 kmem_cache_destroy(ip_vs_conn_cachep
);
1136 proc_net_remove(&init_net
, "ip_vs_conn");
1137 proc_net_remove(&init_net
, "ip_vs_conn_sync");
1138 vfree(ip_vs_conn_tab
);