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  1/*
  2 * net/tipc/server.c: TIPC server infrastructure
  3 *
  4 * Copyright (c) 2012-2013, Wind River Systems
  5 * Copyright (c) 2017-2018, Ericsson AB
  6 * All rights reserved.
  7 *
  8 * Redistribution and use in source and binary forms, with or without
  9 * modification, are permitted provided that the following conditions are met:
 10 *
 11 * 1. Redistributions of source code must retain the above copyright
 12 *    notice, this list of conditions and the following disclaimer.
 13 * 2. Redistributions in binary form must reproduce the above copyright
 14 *    notice, this list of conditions and the following disclaimer in the
 15 *    documentation and/or other materials provided with the distribution.
 16 * 3. Neither the names of the copyright holders nor the names of its
 17 *    contributors may be used to endorse or promote products derived from
 18 *    this software without specific prior written permission.
 19 *
 20 * Alternatively, this software may be distributed under the terms of the
 21 * GNU General Public License ("GPL") version 2 as published by the Free
 22 * Software Foundation.
 23 *
 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 34 * POSSIBILITY OF SUCH DAMAGE.
 35 */
 36
 37#include "subscr.h"
 38#include "topsrv.h"
 39#include "core.h"
 40#include "socket.h"
 41#include "addr.h"
 42#include "msg.h"
 43#include <net/sock.h>
 44#include <linux/module.h>
 45
 46/* Number of messages to send before rescheduling */
 47#define MAX_SEND_MSG_COUNT	25
 48#define MAX_RECV_MSG_COUNT	25
 49#define CF_CONNECTED		1
 50#define CF_SERVER		2
 51
 52#define TIPC_SERVER_NAME_LEN	32
 53
 54/**
 55 * struct tipc_topsrv - TIPC server structure
 56 * @conn_idr: identifier set of connection
 57 * @idr_lock: protect the connection identifier set
 58 * @idr_in_use: amount of allocated identifier entry
 59 * @net: network namspace instance
 60 * @rcvbuf_cache: memory cache of server receive buffer
 61 * @rcv_wq: receive workqueue
 62 * @send_wq: send workqueue
 63 * @max_rcvbuf_size: maximum permitted receive message length
 64 * @tipc_conn_new: callback will be called when new connection is incoming
 65 * @tipc_conn_release: callback will be called before releasing the connection
 66 * @tipc_conn_recvmsg: callback will be called when message arrives
 67 * @name: server name
 68 * @imp: message importance
 69 * @type: socket type
 70 */
 71struct tipc_topsrv {
 72	struct idr conn_idr;
 73	spinlock_t idr_lock; /* for idr list */
 74	int idr_in_use;
 75	struct net *net;
 76	struct work_struct awork;
 77	struct workqueue_struct *rcv_wq;
 78	struct workqueue_struct *send_wq;
 79	int max_rcvbuf_size;
 80	struct socket *listener;
 81	char name[TIPC_SERVER_NAME_LEN];
 82};
 83
 84/**
 85 * struct tipc_conn - TIPC connection structure
 86 * @kref: reference counter to connection object
 87 * @conid: connection identifier
 88 * @sock: socket handler associated with connection
 89 * @flags: indicates connection state
 90 * @server: pointer to connected server
 91 * @sub_list: lsit to all pertaing subscriptions
 92 * @sub_lock: lock protecting the subscription list
 93 * @outqueue_lock: control access to the outqueue
 94 * @rwork: receive work item
 95 * @rx_action: what to do when connection socket is active
 96 * @outqueue: pointer to first outbound message in queue
 97 * @outqueue_lock: control access to the outqueue
 98 * @swork: send work item
 99 */
100struct tipc_conn {
101	struct kref kref;
102	int conid;
103	struct socket *sock;
104	unsigned long flags;
105	struct tipc_topsrv *server;
106	struct list_head sub_list;
107	spinlock_t sub_lock; /* for subscription list */
108	struct work_struct rwork;
109	struct list_head outqueue;
110	spinlock_t outqueue_lock; /* for outqueue */
111	struct work_struct swork;
112};
113
114/* An entry waiting to be sent */
115struct outqueue_entry {
116	bool inactive;
117	struct tipc_event evt;
118	struct list_head list;
119};
120
121static void tipc_conn_recv_work(struct work_struct *work);
122static void tipc_conn_send_work(struct work_struct *work);
123static void tipc_topsrv_kern_evt(struct net *net, struct tipc_event *evt);
124static void tipc_conn_delete_sub(struct tipc_conn *con, struct tipc_subscr *s);
125
126static bool connected(struct tipc_conn *con)
127{
128	return con && test_bit(CF_CONNECTED, &con->flags);
129}
130
131static void tipc_conn_kref_release(struct kref *kref)
132{
133	struct tipc_conn *con = container_of(kref, struct tipc_conn, kref);
134	struct tipc_topsrv *s = con->server;
135	struct outqueue_entry *e, *safe;
136
137	spin_lock_bh(&s->idr_lock);
138	idr_remove(&s->conn_idr, con->conid);
139	s->idr_in_use--;
140	spin_unlock_bh(&s->idr_lock);
141	if (con->sock)
142		sock_release(con->sock);
143
144	spin_lock_bh(&con->outqueue_lock);
145	list_for_each_entry_safe(e, safe, &con->outqueue, list) {
146		list_del(&e->list);
147		kfree(e);
148	}
149	spin_unlock_bh(&con->outqueue_lock);
150	kfree(con);
151}
152
153static void conn_put(struct tipc_conn *con)
154{
155	kref_put(&con->kref, tipc_conn_kref_release);
156}
157
158static void conn_get(struct tipc_conn *con)
159{
160	kref_get(&con->kref);
161}
162
163static void tipc_conn_close(struct tipc_conn *con)
164{
165	struct sock *sk = con->sock->sk;
166	bool disconnect = false;
167
168	write_lock_bh(&sk->sk_callback_lock);
169	disconnect = test_and_clear_bit(CF_CONNECTED, &con->flags);
170
171	if (disconnect) {
172		sk->sk_user_data = NULL;
173		tipc_conn_delete_sub(con, NULL);
174	}
175	write_unlock_bh(&sk->sk_callback_lock);
176
177	/* Handle concurrent calls from sending and receiving threads */
178	if (!disconnect)
179		return;
180
181	/* Don't flush pending works, -just let them expire */
182	kernel_sock_shutdown(con->sock, SHUT_RDWR);
183
184	conn_put(con);
185}
186
187static struct tipc_conn *tipc_conn_alloc(struct tipc_topsrv *s)
188{
189	struct tipc_conn *con;
190	int ret;
191
192	con = kzalloc(sizeof(*con), GFP_ATOMIC);
193	if (!con)
194		return ERR_PTR(-ENOMEM);
195
196	kref_init(&con->kref);
197	INIT_LIST_HEAD(&con->outqueue);
198	INIT_LIST_HEAD(&con->sub_list);
199	spin_lock_init(&con->outqueue_lock);
200	spin_lock_init(&con->sub_lock);
201	INIT_WORK(&con->swork, tipc_conn_send_work);
202	INIT_WORK(&con->rwork, tipc_conn_recv_work);
203
204	spin_lock_bh(&s->idr_lock);
205	ret = idr_alloc(&s->conn_idr, con, 0, 0, GFP_ATOMIC);
206	if (ret < 0) {
207		kfree(con);
208		spin_unlock_bh(&s->idr_lock);
209		return ERR_PTR(-ENOMEM);
210	}
211	con->conid = ret;
212	s->idr_in_use++;
213	spin_unlock_bh(&s->idr_lock);
214
215	set_bit(CF_CONNECTED, &con->flags);
216	con->server = s;
217
218	return con;
219}
220
221static struct tipc_conn *tipc_conn_lookup(struct tipc_topsrv *s, int conid)
222{
223	struct tipc_conn *con;
224
225	spin_lock_bh(&s->idr_lock);
226	con = idr_find(&s->conn_idr, conid);
227	if (!connected(con) || !kref_get_unless_zero(&con->kref))
228		con = NULL;
229	spin_unlock_bh(&s->idr_lock);
230	return con;
231}
232
233/* tipc_conn_delete_sub - delete a specific or all subscriptions
234 * for a given subscriber
235 */
236static void tipc_conn_delete_sub(struct tipc_conn *con, struct tipc_subscr *s)
237{
238	struct tipc_net *tn = tipc_net(con->server->net);
239	struct list_head *sub_list = &con->sub_list;
240	struct tipc_subscription *sub, *tmp;
241
242	spin_lock_bh(&con->sub_lock);
243	list_for_each_entry_safe(sub, tmp, sub_list, sub_list) {
244		if (!s || !memcmp(s, &sub->evt.s, sizeof(*s))) {
245			tipc_sub_unsubscribe(sub);
246			atomic_dec(&tn->subscription_count);
247		} else if (s) {
248			break;
249		}
250	}
251	spin_unlock_bh(&con->sub_lock);
252}
253
254static void tipc_conn_send_to_sock(struct tipc_conn *con)
255{
256	struct list_head *queue = &con->outqueue;
257	struct tipc_topsrv *srv = con->server;
258	struct outqueue_entry *e;
259	struct tipc_event *evt;
260	struct msghdr msg;
261	struct kvec iov;
262	int count = 0;
263	int ret;
264
265	spin_lock_bh(&con->outqueue_lock);
266
267	while (!list_empty(queue)) {
268		e = list_first_entry(queue, struct outqueue_entry, list);
269		evt = &e->evt;
270		spin_unlock_bh(&con->outqueue_lock);
271
272		if (e->inactive)
273			tipc_conn_delete_sub(con, &evt->s);
274
275		memset(&msg, 0, sizeof(msg));
276		msg.msg_flags = MSG_DONTWAIT;
277		iov.iov_base = evt;
278		iov.iov_len = sizeof(*evt);
279		msg.msg_name = NULL;
280
281		if (con->sock) {
282			ret = kernel_sendmsg(con->sock, &msg, &iov,
283					     1, sizeof(*evt));
284			if (ret == -EWOULDBLOCK || ret == 0) {
285				cond_resched();
286				return;
287			} else if (ret < 0) {
288				return tipc_conn_close(con);
289			}
290		} else {
291			tipc_topsrv_kern_evt(srv->net, evt);
292		}
293
294		/* Don't starve users filling buffers */
295		if (++count >= MAX_SEND_MSG_COUNT) {
296			cond_resched();
297			count = 0;
298		}
299		spin_lock_bh(&con->outqueue_lock);
300		list_del(&e->list);
301		kfree(e);
302	}
303	spin_unlock_bh(&con->outqueue_lock);
304}
305
306static void tipc_conn_send_work(struct work_struct *work)
307{
308	struct tipc_conn *con = container_of(work, struct tipc_conn, swork);
309
310	if (connected(con))
311		tipc_conn_send_to_sock(con);
312
313	conn_put(con);
314}
315
316/* tipc_conn_queue_evt() - interrupt level call from a subscription instance
317 * The queued work is launched into tipc_send_work()->tipc_send_to_sock()
318 */
319void tipc_topsrv_queue_evt(struct net *net, int conid,
320			   u32 event, struct tipc_event *evt)
321{
322	struct tipc_topsrv *srv = tipc_topsrv(net);
323	struct outqueue_entry *e;
324	struct tipc_conn *con;
325
326	con = tipc_conn_lookup(srv, conid);
327	if (!con)
328		return;
329
330	if (!connected(con))
331		goto err;
332
333	e = kmalloc(sizeof(*e), GFP_ATOMIC);
334	if (!e)
335		goto err;
336	e->inactive = (event == TIPC_SUBSCR_TIMEOUT);
337	memcpy(&e->evt, evt, sizeof(*evt));
338	spin_lock_bh(&con->outqueue_lock);
339	list_add_tail(&e->list, &con->outqueue);
340	spin_unlock_bh(&con->outqueue_lock);
341
342	if (queue_work(srv->send_wq, &con->swork))
343		return;
344err:
345	conn_put(con);
346}
347
348/* tipc_conn_write_space - interrupt callback after a sendmsg EAGAIN
349 * Indicates that there now is more space in the send buffer
350 * The queued work is launched into tipc_send_work()->tipc_conn_send_to_sock()
351 */
352static void tipc_conn_write_space(struct sock *sk)
353{
354	struct tipc_conn *con;
355
356	read_lock_bh(&sk->sk_callback_lock);
357	con = sk->sk_user_data;
358	if (connected(con)) {
359		conn_get(con);
360		if (!queue_work(con->server->send_wq, &con->swork))
361			conn_put(con);
362	}
363	read_unlock_bh(&sk->sk_callback_lock);
364}
365
366static int tipc_conn_rcv_sub(struct tipc_topsrv *srv,
367			     struct tipc_conn *con,
368			     struct tipc_subscr *s)
369{
370	struct tipc_net *tn = tipc_net(srv->net);
371	struct tipc_subscription *sub;
372
373	if (tipc_sub_read(s, filter) & TIPC_SUB_CANCEL) {
374		tipc_conn_delete_sub(con, s);
375		return 0;
376	}
377	if (atomic_read(&tn->subscription_count) >= TIPC_MAX_SUBSCR) {
378		pr_warn("Subscription rejected, max (%u)\n", TIPC_MAX_SUBSCR);
379		return -1;
380	}
381	sub = tipc_sub_subscribe(srv->net, s, con->conid);
382	if (!sub)
383		return -1;
384	atomic_inc(&tn->subscription_count);
385	spin_lock_bh(&con->sub_lock);
386	list_add(&sub->sub_list, &con->sub_list);
387	spin_unlock_bh(&con->sub_lock);
388	return 0;
389}
390
391static int tipc_conn_rcv_from_sock(struct tipc_conn *con)
392{
393	struct tipc_topsrv *srv = con->server;
394	struct sock *sk = con->sock->sk;
395	struct msghdr msg = {};
396	struct tipc_subscr s;
397	struct kvec iov;
398	int ret;
399
400	iov.iov_base = &s;
401	iov.iov_len = sizeof(s);
402	msg.msg_name = NULL;
403	iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, iov.iov_len);
404	ret = sock_recvmsg(con->sock, &msg, MSG_DONTWAIT);
405	if (ret == -EWOULDBLOCK)
406		return -EWOULDBLOCK;
407	if (ret > 0) {
408		read_lock_bh(&sk->sk_callback_lock);
409		ret = tipc_conn_rcv_sub(srv, con, &s);
410		read_unlock_bh(&sk->sk_callback_lock);
411	}
412	if (ret < 0)
413		tipc_conn_close(con);
414
415	return ret;
416}
417
418static void tipc_conn_recv_work(struct work_struct *work)
419{
420	struct tipc_conn *con = container_of(work, struct tipc_conn, rwork);
421	int count = 0;
422
423	while (connected(con)) {
424		if (tipc_conn_rcv_from_sock(con))
425			break;
426
427		/* Don't flood Rx machine */
428		if (++count >= MAX_RECV_MSG_COUNT) {
429			cond_resched();
430			count = 0;
431		}
432	}
433	conn_put(con);
434}
435
436/* tipc_conn_data_ready - interrupt callback indicating the socket has data
437 * The queued work is launched into tipc_recv_work()->tipc_conn_rcv_from_sock()
438 */
439static void tipc_conn_data_ready(struct sock *sk)
440{
441	struct tipc_conn *con;
442
443	read_lock_bh(&sk->sk_callback_lock);
444	con = sk->sk_user_data;
445	if (connected(con)) {
446		conn_get(con);
447		if (!queue_work(con->server->rcv_wq, &con->rwork))
448			conn_put(con);
449	}
450	read_unlock_bh(&sk->sk_callback_lock);
451}
452
453static void tipc_topsrv_accept(struct work_struct *work)
454{
455	struct tipc_topsrv *srv = container_of(work, struct tipc_topsrv, awork);
456	struct socket *lsock = srv->listener;
457	struct socket *newsock;
458	struct tipc_conn *con;
459	struct sock *newsk;
460	int ret;
461
462	while (1) {
463		ret = kernel_accept(lsock, &newsock, O_NONBLOCK);
464		if (ret < 0)
465			return;
466		con = tipc_conn_alloc(srv);
467		if (IS_ERR(con)) {
468			ret = PTR_ERR(con);
469			sock_release(newsock);
470			return;
471		}
472		/* Register callbacks */
473		newsk = newsock->sk;
474		write_lock_bh(&newsk->sk_callback_lock);
475		newsk->sk_data_ready = tipc_conn_data_ready;
476		newsk->sk_write_space = tipc_conn_write_space;
477		newsk->sk_user_data = con;
478		con->sock = newsock;
479		write_unlock_bh(&newsk->sk_callback_lock);
480
481		/* Wake up receive process in case of 'SYN+' message */
482		newsk->sk_data_ready(newsk);
483	}
484}
485
486/* tipc_toprsv_listener_data_ready - interrupt callback with connection request
487 * The queued job is launched into tipc_topsrv_accept()
488 */
489static void tipc_topsrv_listener_data_ready(struct sock *sk)
490{
491	struct tipc_topsrv *srv;
492
493	read_lock_bh(&sk->sk_callback_lock);
494	srv = sk->sk_user_data;
495	if (srv->listener)
496		queue_work(srv->rcv_wq, &srv->awork);
497	read_unlock_bh(&sk->sk_callback_lock);
498}
499
500static int tipc_topsrv_create_listener(struct tipc_topsrv *srv)
501{
502	int imp = TIPC_CRITICAL_IMPORTANCE;
503	struct socket *lsock = NULL;
504	struct sockaddr_tipc saddr;
505	struct sock *sk;
506	int rc;
507
508	rc = sock_create_kern(srv->net, AF_TIPC, SOCK_SEQPACKET, 0, &lsock);
509	if (rc < 0)
510		return rc;
511
512	srv->listener = lsock;
513	sk = lsock->sk;
514	write_lock_bh(&sk->sk_callback_lock);
515	sk->sk_data_ready = tipc_topsrv_listener_data_ready;
516	sk->sk_user_data = srv;
517	write_unlock_bh(&sk->sk_callback_lock);
518
519	rc = kernel_setsockopt(lsock, SOL_TIPC, TIPC_IMPORTANCE,
520			       (char *)&imp, sizeof(imp));
521	if (rc < 0)
522		goto err;
523
524	saddr.family	                = AF_TIPC;
525	saddr.addrtype		        = TIPC_ADDR_NAMESEQ;
526	saddr.addr.nameseq.type	        = TIPC_TOP_SRV;
527	saddr.addr.nameseq.lower	= TIPC_TOP_SRV;
528	saddr.addr.nameseq.upper	= TIPC_TOP_SRV;
529	saddr.scope			= TIPC_NODE_SCOPE;
530
531	rc = kernel_bind(lsock, (struct sockaddr *)&saddr, sizeof(saddr));
532	if (rc < 0)
533		goto err;
534	rc = kernel_listen(lsock, 0);
535	if (rc < 0)
536		goto err;
537
538	/* As server's listening socket owner and creator is the same module,
539	 * we have to decrease TIPC module reference count to guarantee that
540	 * it remains zero after the server socket is created, otherwise,
541	 * executing "rmmod" command is unable to make TIPC module deleted
542	 * after TIPC module is inserted successfully.
543	 *
544	 * However, the reference count is ever increased twice in
545	 * sock_create_kern(): one is to increase the reference count of owner
546	 * of TIPC socket's proto_ops struct; another is to increment the
547	 * reference count of owner of TIPC proto struct. Therefore, we must
548	 * decrement the module reference count twice to ensure that it keeps
549	 * zero after server's listening socket is created. Of course, we
550	 * must bump the module reference count twice as well before the socket
551	 * is closed.
552	 */
553	module_put(lsock->ops->owner);
554	module_put(sk->sk_prot_creator->owner);
555
556	return 0;
557err:
558	sock_release(lsock);
559	return -EINVAL;
560}
561
562bool tipc_topsrv_kern_subscr(struct net *net, u32 port, u32 type, u32 lower,
563			     u32 upper, u32 filter, int *conid)
564{
565	struct tipc_subscr sub;
566	struct tipc_conn *con;
567	int rc;
568
569	sub.seq.type = type;
570	sub.seq.lower = lower;
571	sub.seq.upper = upper;
572	sub.timeout = TIPC_WAIT_FOREVER;
573	sub.filter = filter;
574	*(u32 *)&sub.usr_handle = port;
575
576	con = tipc_conn_alloc(tipc_topsrv(net));
577	if (IS_ERR(con))
578		return false;
579
580	*conid = con->conid;
581	con->sock = NULL;
582	rc = tipc_conn_rcv_sub(tipc_topsrv(net), con, &sub);
583	if (rc >= 0)
584		return true;
585	conn_put(con);
586	return false;
587}
588
589void tipc_topsrv_kern_unsubscr(struct net *net, int conid)
590{
591	struct tipc_conn *con;
592
593	con = tipc_conn_lookup(tipc_topsrv(net), conid);
594	if (!con)
595		return;
596
597	test_and_clear_bit(CF_CONNECTED, &con->flags);
598	tipc_conn_delete_sub(con, NULL);
599	conn_put(con);
600	conn_put(con);
601}
602
603static void tipc_topsrv_kern_evt(struct net *net, struct tipc_event *evt)
604{
605	u32 port = *(u32 *)&evt->s.usr_handle;
606	u32 self = tipc_own_addr(net);
607	struct sk_buff_head evtq;
608	struct sk_buff *skb;
609
610	skb = tipc_msg_create(TOP_SRV, 0, INT_H_SIZE, sizeof(*evt),
611			      self, self, port, port, 0);
612	if (!skb)
613		return;
614	msg_set_dest_droppable(buf_msg(skb), true);
615	memcpy(msg_data(buf_msg(skb)), evt, sizeof(*evt));
616	skb_queue_head_init(&evtq);
617	__skb_queue_tail(&evtq, skb);
618	tipc_sk_rcv(net, &evtq);
619}
620
621static int tipc_topsrv_work_start(struct tipc_topsrv *s)
622{
623	s->rcv_wq = alloc_ordered_workqueue("tipc_rcv", 0);
624	if (!s->rcv_wq) {
625		pr_err("can't start tipc receive workqueue\n");
626		return -ENOMEM;
627	}
628
629	s->send_wq = alloc_ordered_workqueue("tipc_send", 0);
630	if (!s->send_wq) {
631		pr_err("can't start tipc send workqueue\n");
632		destroy_workqueue(s->rcv_wq);
633		return -ENOMEM;
634	}
635
636	return 0;
637}
638
639static void tipc_topsrv_work_stop(struct tipc_topsrv *s)
640{
641	destroy_workqueue(s->rcv_wq);
642	destroy_workqueue(s->send_wq);
643}
644
645int tipc_topsrv_start(struct net *net)
646{
647	struct tipc_net *tn = tipc_net(net);
648	const char name[] = "topology_server";
649	struct tipc_topsrv *srv;
650	int ret;
651
652	srv = kzalloc(sizeof(*srv), GFP_ATOMIC);
653	if (!srv)
654		return -ENOMEM;
655
656	srv->net = net;
657	srv->max_rcvbuf_size = sizeof(struct tipc_subscr);
658	INIT_WORK(&srv->awork, tipc_topsrv_accept);
659
660	strncpy(srv->name, name, strlen(name) + 1);
661	tn->topsrv = srv;
662	atomic_set(&tn->subscription_count, 0);
663
664	spin_lock_init(&srv->idr_lock);
665	idr_init(&srv->conn_idr);
666	srv->idr_in_use = 0;
667
668	ret = tipc_topsrv_work_start(srv);
669	if (ret < 0)
670		return ret;
671
672	ret = tipc_topsrv_create_listener(srv);
673	if (ret < 0)
674		tipc_topsrv_work_stop(srv);
675
676	return ret;
677}
678
679void tipc_topsrv_stop(struct net *net)
680{
681	struct tipc_topsrv *srv = tipc_topsrv(net);
682	struct socket *lsock = srv->listener;
683	struct tipc_conn *con;
684	int id;
685
686	spin_lock_bh(&srv->idr_lock);
687	for (id = 0; srv->idr_in_use; id++) {
688		con = idr_find(&srv->conn_idr, id);
689		if (con) {
690			spin_unlock_bh(&srv->idr_lock);
691			tipc_conn_close(con);
692			spin_lock_bh(&srv->idr_lock);
693		}
694	}
695	__module_get(lsock->ops->owner);
696	__module_get(lsock->sk->sk_prot_creator->owner);
697	srv->listener = NULL;
698	spin_unlock_bh(&srv->idr_lock);
699	sock_release(lsock);
700	tipc_topsrv_work_stop(srv);
701	idr_destroy(&srv->conn_idr);
702	kfree(srv);
703}