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inet: Allowing more than 64k connections and heavily optimize bind(0) time.
[~shefty/rdma-dev.git] / net / ipv4 / inet_connection_sock.c
1 /*
2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
3  *              operating system.  INET is implemented using the  BSD Socket
4  *              interface as the means of communication with the user level.
5  *
6  *              Support for INET connection oriented protocols.
7  *
8  * Authors:     See the TCP sources
9  *
10  *              This program is free software; you can redistribute it and/or
11  *              modify it under the terms of the GNU General Public License
12  *              as published by the Free Software Foundation; either version
13  *              2 of the License, or(at your option) any later version.
14  */
15
16 #include <linux/module.h>
17 #include <linux/jhash.h>
18
19 #include <net/inet_connection_sock.h>
20 #include <net/inet_hashtables.h>
21 #include <net/inet_timewait_sock.h>
22 #include <net/ip.h>
23 #include <net/route.h>
24 #include <net/tcp_states.h>
25 #include <net/xfrm.h>
26
27 #ifdef INET_CSK_DEBUG
28 const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n";
29 EXPORT_SYMBOL(inet_csk_timer_bug_msg);
30 #endif
31
32 /*
33  * This struct holds the first and last local port number.
34  */
35 struct local_ports sysctl_local_ports __read_mostly = {
36         .lock = SEQLOCK_UNLOCKED,
37         .range = { 32768, 61000 },
38 };
39
40 void inet_get_local_port_range(int *low, int *high)
41 {
42         unsigned seq;
43         do {
44                 seq = read_seqbegin(&sysctl_local_ports.lock);
45
46                 *low = sysctl_local_ports.range[0];
47                 *high = sysctl_local_ports.range[1];
48         } while (read_seqretry(&sysctl_local_ports.lock, seq));
49 }
50 EXPORT_SYMBOL(inet_get_local_port_range);
51
52 int inet_csk_bind_conflict(const struct sock *sk,
53                            const struct inet_bind_bucket *tb)
54 {
55         const __be32 sk_rcv_saddr = inet_rcv_saddr(sk);
56         struct sock *sk2;
57         struct hlist_node *node;
58         int reuse = sk->sk_reuse;
59
60         /*
61          * Unlike other sk lookup places we do not check
62          * for sk_net here, since _all_ the socks listed
63          * in tb->owners list belong to the same net - the
64          * one this bucket belongs to.
65          */
66
67         sk_for_each_bound(sk2, node, &tb->owners) {
68                 if (sk != sk2 &&
69                     !inet_v6_ipv6only(sk2) &&
70                     (!sk->sk_bound_dev_if ||
71                      !sk2->sk_bound_dev_if ||
72                      sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
73                         if (!reuse || !sk2->sk_reuse ||
74                             sk2->sk_state == TCP_LISTEN) {
75                                 const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
76                                 if (!sk2_rcv_saddr || !sk_rcv_saddr ||
77                                     sk2_rcv_saddr == sk_rcv_saddr)
78                                         break;
79                         }
80                 }
81         }
82         return node != NULL;
83 }
84
85 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
86
87 /* Obtain a reference to a local port for the given sock,
88  * if snum is zero it means select any available local port.
89  */
90 int inet_csk_get_port(struct sock *sk, unsigned short snum)
91 {
92         struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
93         struct inet_bind_hashbucket *head;
94         struct hlist_node *node;
95         struct inet_bind_bucket *tb;
96         int ret, attempts = 5;
97         struct net *net = sock_net(sk);
98         int smallest_size = -1, smallest_rover;
99
100         local_bh_disable();
101         if (!snum) {
102                 int remaining, rover, low, high;
103
104 again:
105                 inet_get_local_port_range(&low, &high);
106                 remaining = (high - low) + 1;
107                 smallest_rover = rover = net_random() % remaining + low;
108
109                 smallest_size = -1;
110                 do {
111                         head = &hashinfo->bhash[inet_bhashfn(net, rover,
112                                         hashinfo->bhash_size)];
113                         spin_lock(&head->lock);
114                         inet_bind_bucket_for_each(tb, node, &head->chain)
115                                 if (ib_net(tb) == net && tb->port == rover) {
116                                         if (tb->fastreuse > 0 &&
117                                             sk->sk_reuse &&
118                                             sk->sk_state != TCP_LISTEN &&
119                                             (tb->num_owners < smallest_size || smallest_size == -1)) {
120                                                 smallest_size = tb->num_owners;
121                                                 smallest_rover = rover;
122                                                 if (hashinfo->bsockets > (high - low) + 1) {
123                                                         spin_unlock(&head->lock);
124                                                         snum = smallest_rover;
125                                                         goto have_snum;
126                                                 }
127                                         }
128                                         goto next;
129                                 }
130                         break;
131                 next:
132                         spin_unlock(&head->lock);
133                         if (++rover > high)
134                                 rover = low;
135                 } while (--remaining > 0);
136
137                 /* Exhausted local port range during search?  It is not
138                  * possible for us to be holding one of the bind hash
139                  * locks if this test triggers, because if 'remaining'
140                  * drops to zero, we broke out of the do/while loop at
141                  * the top level, not from the 'break;' statement.
142                  */
143                 ret = 1;
144                 if (remaining <= 0) {
145                         if (smallest_size != -1) {
146                                 snum = smallest_rover;
147                                 goto have_snum;
148                         }
149                         goto fail;
150                 }
151                 /* OK, here is the one we will use.  HEAD is
152                  * non-NULL and we hold it's mutex.
153                  */
154                 snum = rover;
155         } else {
156 have_snum:
157                 head = &hashinfo->bhash[inet_bhashfn(net, snum,
158                                 hashinfo->bhash_size)];
159                 spin_lock(&head->lock);
160                 inet_bind_bucket_for_each(tb, node, &head->chain)
161                         if (ib_net(tb) == net && tb->port == snum)
162                                 goto tb_found;
163         }
164         tb = NULL;
165         goto tb_not_found;
166 tb_found:
167         if (!hlist_empty(&tb->owners)) {
168                 if (tb->fastreuse > 0 &&
169                     sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
170                     smallest_size == -1) {
171                         goto success;
172                 } else {
173                         ret = 1;
174                         if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
175                                 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN && --attempts >= 0) {
176                                         spin_unlock(&head->lock);
177                                         goto again;
178                                 }
179                                 goto fail_unlock;
180                         }
181                 }
182         }
183 tb_not_found:
184         ret = 1;
185         if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
186                                         net, head, snum)) == NULL)
187                 goto fail_unlock;
188         if (hlist_empty(&tb->owners)) {
189                 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
190                         tb->fastreuse = 1;
191                 else
192                         tb->fastreuse = 0;
193         } else if (tb->fastreuse &&
194                    (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
195                 tb->fastreuse = 0;
196 success:
197         if (!inet_csk(sk)->icsk_bind_hash)
198                 inet_bind_hash(sk, tb, snum);
199         WARN_ON(inet_csk(sk)->icsk_bind_hash != tb);
200         ret = 0;
201
202 fail_unlock:
203         spin_unlock(&head->lock);
204 fail:
205         local_bh_enable();
206         return ret;
207 }
208
209 EXPORT_SYMBOL_GPL(inet_csk_get_port);
210
211 /*
212  * Wait for an incoming connection, avoid race conditions. This must be called
213  * with the socket locked.
214  */
215 static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
216 {
217         struct inet_connection_sock *icsk = inet_csk(sk);
218         DEFINE_WAIT(wait);
219         int err;
220
221         /*
222          * True wake-one mechanism for incoming connections: only
223          * one process gets woken up, not the 'whole herd'.
224          * Since we do not 'race & poll' for established sockets
225          * anymore, the common case will execute the loop only once.
226          *
227          * Subtle issue: "add_wait_queue_exclusive()" will be added
228          * after any current non-exclusive waiters, and we know that
229          * it will always _stay_ after any new non-exclusive waiters
230          * because all non-exclusive waiters are added at the
231          * beginning of the wait-queue. As such, it's ok to "drop"
232          * our exclusiveness temporarily when we get woken up without
233          * having to remove and re-insert us on the wait queue.
234          */
235         for (;;) {
236                 prepare_to_wait_exclusive(sk->sk_sleep, &wait,
237                                           TASK_INTERRUPTIBLE);
238                 release_sock(sk);
239                 if (reqsk_queue_empty(&icsk->icsk_accept_queue))
240                         timeo = schedule_timeout(timeo);
241                 lock_sock(sk);
242                 err = 0;
243                 if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
244                         break;
245                 err = -EINVAL;
246                 if (sk->sk_state != TCP_LISTEN)
247                         break;
248                 err = sock_intr_errno(timeo);
249                 if (signal_pending(current))
250                         break;
251                 err = -EAGAIN;
252                 if (!timeo)
253                         break;
254         }
255         finish_wait(sk->sk_sleep, &wait);
256         return err;
257 }
258
259 /*
260  * This will accept the next outstanding connection.
261  */
262 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
263 {
264         struct inet_connection_sock *icsk = inet_csk(sk);
265         struct sock *newsk;
266         int error;
267
268         lock_sock(sk);
269
270         /* We need to make sure that this socket is listening,
271          * and that it has something pending.
272          */
273         error = -EINVAL;
274         if (sk->sk_state != TCP_LISTEN)
275                 goto out_err;
276
277         /* Find already established connection */
278         if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
279                 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
280
281                 /* If this is a non blocking socket don't sleep */
282                 error = -EAGAIN;
283                 if (!timeo)
284                         goto out_err;
285
286                 error = inet_csk_wait_for_connect(sk, timeo);
287                 if (error)
288                         goto out_err;
289         }
290
291         newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
292         WARN_ON(newsk->sk_state == TCP_SYN_RECV);
293 out:
294         release_sock(sk);
295         return newsk;
296 out_err:
297         newsk = NULL;
298         *err = error;
299         goto out;
300 }
301
302 EXPORT_SYMBOL(inet_csk_accept);
303
304 /*
305  * Using different timers for retransmit, delayed acks and probes
306  * We may wish use just one timer maintaining a list of expire jiffies
307  * to optimize.
308  */
309 void inet_csk_init_xmit_timers(struct sock *sk,
310                                void (*retransmit_handler)(unsigned long),
311                                void (*delack_handler)(unsigned long),
312                                void (*keepalive_handler)(unsigned long))
313 {
314         struct inet_connection_sock *icsk = inet_csk(sk);
315
316         setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
317                         (unsigned long)sk);
318         setup_timer(&icsk->icsk_delack_timer, delack_handler,
319                         (unsigned long)sk);
320         setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
321         icsk->icsk_pending = icsk->icsk_ack.pending = 0;
322 }
323
324 EXPORT_SYMBOL(inet_csk_init_xmit_timers);
325
326 void inet_csk_clear_xmit_timers(struct sock *sk)
327 {
328         struct inet_connection_sock *icsk = inet_csk(sk);
329
330         icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
331
332         sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
333         sk_stop_timer(sk, &icsk->icsk_delack_timer);
334         sk_stop_timer(sk, &sk->sk_timer);
335 }
336
337 EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
338
339 void inet_csk_delete_keepalive_timer(struct sock *sk)
340 {
341         sk_stop_timer(sk, &sk->sk_timer);
342 }
343
344 EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
345
346 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
347 {
348         sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
349 }
350
351 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
352
353 struct dst_entry *inet_csk_route_req(struct sock *sk,
354                                      const struct request_sock *req)
355 {
356         struct rtable *rt;
357         const struct inet_request_sock *ireq = inet_rsk(req);
358         struct ip_options *opt = inet_rsk(req)->opt;
359         struct flowi fl = { .oif = sk->sk_bound_dev_if,
360                             .nl_u = { .ip4_u =
361                                       { .daddr = ((opt && opt->srr) ?
362                                                   opt->faddr :
363                                                   ireq->rmt_addr),
364                                         .saddr = ireq->loc_addr,
365                                         .tos = RT_CONN_FLAGS(sk) } },
366                             .proto = sk->sk_protocol,
367                             .flags = inet_sk_flowi_flags(sk),
368                             .uli_u = { .ports =
369                                        { .sport = inet_sk(sk)->sport,
370                                          .dport = ireq->rmt_port } } };
371         struct net *net = sock_net(sk);
372
373         security_req_classify_flow(req, &fl);
374         if (ip_route_output_flow(net, &rt, &fl, sk, 0))
375                 goto no_route;
376         if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
377                 goto route_err;
378         return &rt->u.dst;
379
380 route_err:
381         ip_rt_put(rt);
382 no_route:
383         IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
384         return NULL;
385 }
386
387 EXPORT_SYMBOL_GPL(inet_csk_route_req);
388
389 static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
390                                  const u32 rnd, const u32 synq_hsize)
391 {
392         return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
393 }
394
395 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
396 #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
397 #else
398 #define AF_INET_FAMILY(fam) 1
399 #endif
400
401 struct request_sock *inet_csk_search_req(const struct sock *sk,
402                                          struct request_sock ***prevp,
403                                          const __be16 rport, const __be32 raddr,
404                                          const __be32 laddr)
405 {
406         const struct inet_connection_sock *icsk = inet_csk(sk);
407         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
408         struct request_sock *req, **prev;
409
410         for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
411                                                     lopt->nr_table_entries)];
412              (req = *prev) != NULL;
413              prev = &req->dl_next) {
414                 const struct inet_request_sock *ireq = inet_rsk(req);
415
416                 if (ireq->rmt_port == rport &&
417                     ireq->rmt_addr == raddr &&
418                     ireq->loc_addr == laddr &&
419                     AF_INET_FAMILY(req->rsk_ops->family)) {
420                         WARN_ON(req->sk);
421                         *prevp = prev;
422                         break;
423                 }
424         }
425
426         return req;
427 }
428
429 EXPORT_SYMBOL_GPL(inet_csk_search_req);
430
431 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
432                                    unsigned long timeout)
433 {
434         struct inet_connection_sock *icsk = inet_csk(sk);
435         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
436         const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
437                                      lopt->hash_rnd, lopt->nr_table_entries);
438
439         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
440         inet_csk_reqsk_queue_added(sk, timeout);
441 }
442
443 /* Only thing we need from tcp.h */
444 extern int sysctl_tcp_synack_retries;
445
446 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
447
448 void inet_csk_reqsk_queue_prune(struct sock *parent,
449                                 const unsigned long interval,
450                                 const unsigned long timeout,
451                                 const unsigned long max_rto)
452 {
453         struct inet_connection_sock *icsk = inet_csk(parent);
454         struct request_sock_queue *queue = &icsk->icsk_accept_queue;
455         struct listen_sock *lopt = queue->listen_opt;
456         int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
457         int thresh = max_retries;
458         unsigned long now = jiffies;
459         struct request_sock **reqp, *req;
460         int i, budget;
461
462         if (lopt == NULL || lopt->qlen == 0)
463                 return;
464
465         /* Normally all the openreqs are young and become mature
466          * (i.e. converted to established socket) for first timeout.
467          * If synack was not acknowledged for 3 seconds, it means
468          * one of the following things: synack was lost, ack was lost,
469          * rtt is high or nobody planned to ack (i.e. synflood).
470          * When server is a bit loaded, queue is populated with old
471          * open requests, reducing effective size of queue.
472          * When server is well loaded, queue size reduces to zero
473          * after several minutes of work. It is not synflood,
474          * it is normal operation. The solution is pruning
475          * too old entries overriding normal timeout, when
476          * situation becomes dangerous.
477          *
478          * Essentially, we reserve half of room for young
479          * embrions; and abort old ones without pity, if old
480          * ones are about to clog our table.
481          */
482         if (lopt->qlen>>(lopt->max_qlen_log-1)) {
483                 int young = (lopt->qlen_young<<1);
484
485                 while (thresh > 2) {
486                         if (lopt->qlen < young)
487                                 break;
488                         thresh--;
489                         young <<= 1;
490                 }
491         }
492
493         if (queue->rskq_defer_accept)
494                 max_retries = queue->rskq_defer_accept;
495
496         budget = 2 * (lopt->nr_table_entries / (timeout / interval));
497         i = lopt->clock_hand;
498
499         do {
500                 reqp=&lopt->syn_table[i];
501                 while ((req = *reqp) != NULL) {
502                         if (time_after_eq(now, req->expires)) {
503                                 if ((req->retrans < thresh ||
504                                      (inet_rsk(req)->acked && req->retrans < max_retries))
505                                     && !req->rsk_ops->rtx_syn_ack(parent, req)) {
506                                         unsigned long timeo;
507
508                                         if (req->retrans++ == 0)
509                                                 lopt->qlen_young--;
510                                         timeo = min((timeout << req->retrans), max_rto);
511                                         req->expires = now + timeo;
512                                         reqp = &req->dl_next;
513                                         continue;
514                                 }
515
516                                 /* Drop this request */
517                                 inet_csk_reqsk_queue_unlink(parent, req, reqp);
518                                 reqsk_queue_removed(queue, req);
519                                 reqsk_free(req);
520                                 continue;
521                         }
522                         reqp = &req->dl_next;
523                 }
524
525                 i = (i + 1) & (lopt->nr_table_entries - 1);
526
527         } while (--budget > 0);
528
529         lopt->clock_hand = i;
530
531         if (lopt->qlen)
532                 inet_csk_reset_keepalive_timer(parent, interval);
533 }
534
535 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
536
537 struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
538                             const gfp_t priority)
539 {
540         struct sock *newsk = sk_clone(sk, priority);
541
542         if (newsk != NULL) {
543                 struct inet_connection_sock *newicsk = inet_csk(newsk);
544
545                 newsk->sk_state = TCP_SYN_RECV;
546                 newicsk->icsk_bind_hash = NULL;
547
548                 inet_sk(newsk)->dport = inet_rsk(req)->rmt_port;
549                 inet_sk(newsk)->num = ntohs(inet_rsk(req)->loc_port);
550                 inet_sk(newsk)->sport = inet_rsk(req)->loc_port;
551                 newsk->sk_write_space = sk_stream_write_space;
552
553                 newicsk->icsk_retransmits = 0;
554                 newicsk->icsk_backoff     = 0;
555                 newicsk->icsk_probes_out  = 0;
556
557                 /* Deinitialize accept_queue to trap illegal accesses. */
558                 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
559
560                 security_inet_csk_clone(newsk, req);
561         }
562         return newsk;
563 }
564
565 EXPORT_SYMBOL_GPL(inet_csk_clone);
566
567 /*
568  * At this point, there should be no process reference to this
569  * socket, and thus no user references at all.  Therefore we
570  * can assume the socket waitqueue is inactive and nobody will
571  * try to jump onto it.
572  */
573 void inet_csk_destroy_sock(struct sock *sk)
574 {
575         WARN_ON(sk->sk_state != TCP_CLOSE);
576         WARN_ON(!sock_flag(sk, SOCK_DEAD));
577
578         /* It cannot be in hash table! */
579         WARN_ON(!sk_unhashed(sk));
580
581         /* If it has not 0 inet_sk(sk)->num, it must be bound */
582         WARN_ON(inet_sk(sk)->num && !inet_csk(sk)->icsk_bind_hash);
583
584         sk->sk_prot->destroy(sk);
585
586         sk_stream_kill_queues(sk);
587
588         xfrm_sk_free_policy(sk);
589
590         sk_refcnt_debug_release(sk);
591
592         percpu_counter_dec(sk->sk_prot->orphan_count);
593         sock_put(sk);
594 }
595
596 EXPORT_SYMBOL(inet_csk_destroy_sock);
597
598 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
599 {
600         struct inet_sock *inet = inet_sk(sk);
601         struct inet_connection_sock *icsk = inet_csk(sk);
602         int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
603
604         if (rc != 0)
605                 return rc;
606
607         sk->sk_max_ack_backlog = 0;
608         sk->sk_ack_backlog = 0;
609         inet_csk_delack_init(sk);
610
611         /* There is race window here: we announce ourselves listening,
612          * but this transition is still not validated by get_port().
613          * It is OK, because this socket enters to hash table only
614          * after validation is complete.
615          */
616         sk->sk_state = TCP_LISTEN;
617         if (!sk->sk_prot->get_port(sk, inet->num)) {
618                 inet->sport = htons(inet->num);
619
620                 sk_dst_reset(sk);
621                 sk->sk_prot->hash(sk);
622
623                 return 0;
624         }
625
626         sk->sk_state = TCP_CLOSE;
627         __reqsk_queue_destroy(&icsk->icsk_accept_queue);
628         return -EADDRINUSE;
629 }
630
631 EXPORT_SYMBOL_GPL(inet_csk_listen_start);
632
633 /*
634  *      This routine closes sockets which have been at least partially
635  *      opened, but not yet accepted.
636  */
637 void inet_csk_listen_stop(struct sock *sk)
638 {
639         struct inet_connection_sock *icsk = inet_csk(sk);
640         struct request_sock *acc_req;
641         struct request_sock *req;
642
643         inet_csk_delete_keepalive_timer(sk);
644
645         /* make all the listen_opt local to us */
646         acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
647
648         /* Following specs, it would be better either to send FIN
649          * (and enter FIN-WAIT-1, it is normal close)
650          * or to send active reset (abort).
651          * Certainly, it is pretty dangerous while synflood, but it is
652          * bad justification for our negligence 8)
653          * To be honest, we are not able to make either
654          * of the variants now.                 --ANK
655          */
656         reqsk_queue_destroy(&icsk->icsk_accept_queue);
657
658         while ((req = acc_req) != NULL) {
659                 struct sock *child = req->sk;
660
661                 acc_req = req->dl_next;
662
663                 local_bh_disable();
664                 bh_lock_sock(child);
665                 WARN_ON(sock_owned_by_user(child));
666                 sock_hold(child);
667
668                 sk->sk_prot->disconnect(child, O_NONBLOCK);
669
670                 sock_orphan(child);
671
672                 percpu_counter_inc(sk->sk_prot->orphan_count);
673
674                 inet_csk_destroy_sock(child);
675
676                 bh_unlock_sock(child);
677                 local_bh_enable();
678                 sock_put(child);
679
680                 sk_acceptq_removed(sk);
681                 __reqsk_free(req);
682         }
683         WARN_ON(sk->sk_ack_backlog);
684 }
685
686 EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
687
688 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
689 {
690         struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
691         const struct inet_sock *inet = inet_sk(sk);
692
693         sin->sin_family         = AF_INET;
694         sin->sin_addr.s_addr    = inet->daddr;
695         sin->sin_port           = inet->dport;
696 }
697
698 EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
699
700 #ifdef CONFIG_COMPAT
701 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
702                                char __user *optval, int __user *optlen)
703 {
704         const struct inet_connection_sock *icsk = inet_csk(sk);
705
706         if (icsk->icsk_af_ops->compat_getsockopt != NULL)
707                 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
708                                                             optval, optlen);
709         return icsk->icsk_af_ops->getsockopt(sk, level, optname,
710                                              optval, optlen);
711 }
712
713 EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
714
715 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
716                                char __user *optval, int optlen)
717 {
718         const struct inet_connection_sock *icsk = inet_csk(sk);
719
720         if (icsk->icsk_af_ops->compat_setsockopt != NULL)
721                 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
722                                                             optval, optlen);
723         return icsk->icsk_af_ops->setsockopt(sk, level, optname,
724                                              optval, optlen);
725 }
726
727 EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
728 #endif