[deliverable/linux.git] / net / tipc / subscr.c

/*
 * net/tipc/subscr.c: TIPC network topology service
 *
 * Copyright (c) 2000-2006, Ericsson AB
 * Copyright (c) 2005-2007, 2010-2013, Wind River Systems
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the names of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "core.h"
#include "name_table.h"
#include "subscr.h"

/**
 * struct tipc_subscriber - TIPC network topology subscriber
 * @kref: reference counter to tipc_subscription object
 * @conid: connection identifier to server connecting to subscriber
 * @lock: control access to subscriber
 * @subscrp_list: list of subscription objects for this subscriber
 */
struct tipc_subscriber {
	struct kref kref;
	int conid;
	spinlock_t lock;
	struct list_head subscrp_list;
};

static void tipc_subscrp_delete(struct tipc_subscription *sub);
static void tipc_subscrb_put(struct tipc_subscriber *subscriber);

/**
 * htohl - convert value to endianness used by destination
 * @in: value to convert
 * @swap: non-zero if endianness must be reversed
 *
 * Returns converted value
 */
static u32 htohl(u32 in, int swap)
{
	return swap ? swab32(in) : in;
}

static void tipc_subscrp_send_event(struct tipc_subscription *sub,
				    u32 found_lower, u32 found_upper,
				    u32 event, u32 port_ref, u32 node)
{
	struct tipc_net *tn = net_generic(sub->net, tipc_net_id);
	struct tipc_subscriber *subscriber = sub->subscriber;
	struct kvec msg_sect;

	msg_sect.iov_base = (void *)&sub->evt;
	msg_sect.iov_len = sizeof(struct tipc_event);
	sub->evt.event = htohl(event, sub->swap);
	sub->evt.found_lower = htohl(found_lower, sub->swap);
	sub->evt.found_upper = htohl(found_upper, sub->swap);
	sub->evt.port.ref = htohl(port_ref, sub->swap);
	sub->evt.port.node = htohl(node, sub->swap);
	tipc_conn_sendmsg(tn->topsrv, subscriber->conid, NULL,
			  msg_sect.iov_base, msg_sect.iov_len);
}

/**
 * tipc_subscrp_check_overlap - test for subscription overlap with the
 * given values
 *
 * Returns 1 if there is overlap, otherwise 0.
 */
int tipc_subscrp_check_overlap(struct tipc_subscription *sub, u32 found_lower,
			       u32 found_upper)
{
	if (found_lower < sub->seq.lower)
		found_lower = sub->seq.lower;
	if (found_upper > sub->seq.upper)
		found_upper = sub->seq.upper;
	if (found_lower > found_upper)
		return 0;
	return 1;
}

void tipc_subscrp_report_overlap(struct tipc_subscription *sub, u32 found_lower,
				 u32 found_upper, u32 event, u32 port_ref,
				 u32 node, int must)
{
	if (!tipc_subscrp_check_overlap(sub, found_lower, found_upper))
		return;
	if (!must && !(sub->filter & TIPC_SUB_PORTS))
		return;

	tipc_subscrp_send_event(sub, found_lower, found_upper, event, port_ref,
				node);
}

static void tipc_subscrp_timeout(unsigned long data)
{
	struct tipc_subscription *sub = (struct tipc_subscription *)data;
	struct tipc_subscriber *subscriber = sub->subscriber;

	/* Notify subscriber of timeout */
	tipc_subscrp_send_event(sub, sub->evt.s.seq.lower, sub->evt.s.seq.upper,
				TIPC_SUBSCR_TIMEOUT, 0, 0);

	spin_lock_bh(&subscriber->lock);
	tipc_subscrp_delete(sub);
	spin_unlock_bh(&subscriber->lock);

	tipc_subscrb_put(subscriber);
}

static void tipc_subscrb_kref_release(struct kref *kref)
{
	struct tipc_subscriber *subcriber = container_of(kref,
					    struct tipc_subscriber, kref);

	kfree(subcriber);
}

static void tipc_subscrb_put(struct tipc_subscriber *subscriber)
{
	kref_put(&subscriber->kref, tipc_subscrb_kref_release);
}

static void tipc_subscrb_get(struct tipc_subscriber *subscriber)
{
	kref_get(&subscriber->kref);
}

static struct tipc_subscriber *tipc_subscrb_create(int conid)
{
	struct tipc_subscriber *subscriber;

	subscriber = kzalloc(sizeof(*subscriber), GFP_ATOMIC);
	if (!subscriber) {
		pr_warn("Subscriber rejected, no memory\n");
		return NULL;
	}
	kref_init(&subscriber->kref);
	INIT_LIST_HEAD(&subscriber->subscrp_list);
	subscriber->conid = conid;
	spin_lock_init(&subscriber->lock);

	return subscriber;
}

static void tipc_subscrb_delete(struct tipc_subscriber *subscriber)
{
	struct tipc_subscription *sub, *temp;

	spin_lock_bh(&subscriber->lock);
	/* Destroy any existing subscriptions for subscriber */
	list_for_each_entry_safe(sub, temp, &subscriber->subscrp_list,
				 subscrp_list) {
		if (del_timer(&sub->timer)) {
			tipc_subscrp_delete(sub);
			tipc_subscrb_put(subscriber);
		}
	}
	spin_unlock_bh(&subscriber->lock);

	tipc_subscrb_put(subscriber);
}

static void tipc_subscrp_delete(struct tipc_subscription *sub)
{
	struct tipc_net *tn = net_generic(sub->net, tipc_net_id);

	tipc_nametbl_unsubscribe(sub);
	list_del(&sub->subscrp_list);
	kfree(sub);
	atomic_dec(&tn->subscription_count);
}

static void tipc_subscrp_cancel(struct tipc_subscr *s,
				struct tipc_subscriber *subscriber)
{
	struct tipc_subscription *sub, *temp;

	spin_lock_bh(&subscriber->lock);
	/* Find first matching subscription, exit if not found */
	list_for_each_entry_safe(sub, temp, &subscriber->subscrp_list,
				 subscrp_list) {
		if (!memcmp(s, &sub->evt.s, sizeof(struct tipc_subscr))) {
			if (del_timer(&sub->timer)) {
				tipc_subscrp_delete(sub);
				tipc_subscrb_put(subscriber);
			}
			break;
		}
	}
	spin_unlock_bh(&subscriber->lock);
}

static int tipc_subscrp_create(struct net *net, struct tipc_subscr *s,
			       struct tipc_subscriber *subscriber,
			       struct tipc_subscription **sub_p)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_subscription *sub;
	int swap;

	/* Determine subscriber's endianness */
	swap = !(s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE));

	/* Detect & process a subscription cancellation request */
	if (s->filter & htohl(TIPC_SUB_CANCEL, swap)) {
		s->filter &= ~htohl(TIPC_SUB_CANCEL, swap);
		tipc_subscrp_cancel(s, subscriber);
		return 0;
	}

	/* Refuse subscription if global limit exceeded */
	if (atomic_read(&tn->subscription_count) >= TIPC_MAX_SUBSCRIPTIONS) {
		pr_warn("Subscription rejected, limit reached (%u)\n",
			TIPC_MAX_SUBSCRIPTIONS);
		return -EINVAL;
	}

	/* Allocate subscription object */
	sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
	if (!sub) {
		pr_warn("Subscription rejected, no memory\n");
		return -ENOMEM;
	}

	/* Initialize subscription object */
	sub->net = net;
	sub->seq.type = htohl(s->seq.type, swap);
	sub->seq.lower = htohl(s->seq.lower, swap);
	sub->seq.upper = htohl(s->seq.upper, swap);
	sub->timeout = msecs_to_jiffies(htohl(s->timeout, swap));
	sub->filter = htohl(s->filter, swap);
	if ((!(sub->filter & TIPC_SUB_PORTS) ==
	     !(sub->filter & TIPC_SUB_SERVICE)) ||
	    (sub->seq.lower > sub->seq.upper)) {
		pr_warn("Subscription rejected, illegal request\n");
		kfree(sub);
		return -EINVAL;
	}
	spin_lock_bh(&subscriber->lock);
	list_add(&sub->subscrp_list, &subscriber->subscrp_list);
	spin_unlock_bh(&subscriber->lock);
	sub->subscriber = subscriber;
	sub->swap = swap;
	memcpy(&sub->evt.s, s, sizeof(*s));
	atomic_inc(&tn->subscription_count);
	setup_timer(&sub->timer, tipc_subscrp_timeout, (unsigned long)sub);
	if (sub->timeout != TIPC_WAIT_FOREVER)
		sub->timeout += jiffies;
	if (!mod_timer(&sub->timer, sub->timeout))
		tipc_subscrb_get(subscriber);
	*sub_p = sub;
	return 0;
}

/* Handle one termination request for the subscriber */
static void tipc_subscrb_shutdown_cb(int conid, void *usr_data)
{
	tipc_subscrb_delete((struct tipc_subscriber *)usr_data);
}

/* Handle one request to create a new subscription for the subscriber */
static void tipc_subscrb_rcv_cb(struct net *net, int conid,
				struct sockaddr_tipc *addr, void *usr_data,
				void *buf, size_t len)
{
	struct tipc_subscriber *subscriber = usr_data;
	struct tipc_subscription *sub = NULL;
	struct tipc_net *tn = net_generic(net, tipc_net_id);

	tipc_subscrp_create(net, (struct tipc_subscr *)buf, subscriber, &sub);
	if (sub)
		tipc_nametbl_subscribe(sub);
	else
		tipc_conn_terminate(tn->topsrv, subscriber->conid);
}

/* Handle one request to establish a new subscriber */
static void *tipc_subscrb_connect_cb(int conid)
{
	return (void *)tipc_subscrb_create(conid);
}

int tipc_topsrv_start(struct net *net)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	const char name[] = "topology_server";
	struct tipc_server *topsrv;
	struct sockaddr_tipc *saddr;

	saddr = kzalloc(sizeof(*saddr), GFP_ATOMIC);
	if (!saddr)
		return -ENOMEM;
	saddr->family			= AF_TIPC;
	saddr->addrtype			= TIPC_ADDR_NAMESEQ;
	saddr->addr.nameseq.type	= TIPC_TOP_SRV;
	saddr->addr.nameseq.lower	= TIPC_TOP_SRV;
	saddr->addr.nameseq.upper	= TIPC_TOP_SRV;
	saddr->scope			= TIPC_NODE_SCOPE;

	topsrv = kzalloc(sizeof(*topsrv), GFP_ATOMIC);
	if (!topsrv) {
		kfree(saddr);
		return -ENOMEM;
	}
	topsrv->net			= net;
	topsrv->saddr			= saddr;
	topsrv->imp			= TIPC_CRITICAL_IMPORTANCE;
	topsrv->type			= SOCK_SEQPACKET;
	topsrv->max_rcvbuf_size		= sizeof(struct tipc_subscr);
	topsrv->tipc_conn_recvmsg	= tipc_subscrb_rcv_cb;
	topsrv->tipc_conn_new		= tipc_subscrb_connect_cb;
	topsrv->tipc_conn_shutdown	= tipc_subscrb_shutdown_cb;

	strncpy(topsrv->name, name, strlen(name) + 1);
	tn->topsrv = topsrv;
	atomic_set(&tn->subscription_count, 0);

	return tipc_server_start(topsrv);
}

void tipc_topsrv_stop(struct net *net)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_server *topsrv = tn->topsrv;

	tipc_server_stop(topsrv);
	kfree(topsrv->saddr);
	kfree(topsrv);
}
Commit	Line	Data
b97bf3fd	1	/*
5b06c85c	2	* net/tipc/subscr.c: TIPC network topology service
c4307285	3	*
593a5f22	4	* Copyright (c) 2000-2006, Ericsson AB
13a2e898	5	* Copyright (c) 2005-2007, 2010-2013, Wind River Systems
b97bf3fd PL	6	* All rights reserved.
b97bf3fd PL	7	*
9ea1fd3c	8	* Redistribution and use in source and binary forms, with or without
b97bf3fd PL	9	* modification, are permitted provided that the following conditions are met:
b97bf3fd PL	10	*
9ea1fd3c PL	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.
b97bf3fd	19	*
9ea1fd3c PL	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
b97bf3fd PL	34	* POSSIBILITY OF SUCH DAMAGE.
	35	*/
	36
	37	#include "core.h"
b97bf3fd	38	#include "name_table.h"
5b06c85c	39	#include "subscr.h"
b97bf3fd PL	40
b97bf3fd PL	41	/**
11f99906	42	* struct tipc_subscriber - TIPC network topology subscriber
00bc00a9	43	* @kref: reference counter to tipc_subscription object
13a2e898	44	* @conid: connection identifier to server connecting to subscriber
963a1855	45	* @lock: control access to subscriber
57f1d186	46	* @subscrp_list: list of subscription objects for this subscriber
b97bf3fd	47	*/
11f99906	48	struct tipc_subscriber {
00bc00a9	49	struct kref kref;
13a2e898 YX	50	int conid;
13a2e898 YX	51	spinlock_t lock;
57f1d186	52	struct list_head subscrp_list;
b97bf3fd PL	53	};
b97bf3fd PL	54
00bc00a9 YX	55	static void tipc_subscrp_delete(struct tipc_subscription *sub);
	56	static void tipc_subscrb_put(struct tipc_subscriber *subscriber);
	57
db5a753b NH	58	/**
	59	* htohl - convert value to endianness used by destination
	60	* @in: value to convert
	61	* @swap: non-zero if endianness must be reversed
	62	*
	63	* Returns converted value
	64	*/
db5a753b NH	65	static u32 htohl(u32 in, int swap)
	66	{
	67	return swap ? swab32(in) : in;
	68	}
	69
57f1d186 YX	70	static void tipc_subscrp_send_event(struct tipc_subscription *sub,
	71	u32 found_lower, u32 found_upper,
	72	u32 event, u32 port_ref, u32 node)
b97bf3fd	73	{
a62fbcce	74	struct tipc_net *tn = net_generic(sub->net, tipc_net_id);
13a2e898 YX	75	struct tipc_subscriber *subscriber = sub->subscriber;
13a2e898 YX	76	struct kvec msg_sect;
b97bf3fd PL	77
	78	msg_sect.iov_base = (void *)&sub->evt;
	79	msg_sect.iov_len = sizeof(struct tipc_event);
db5a753b NH	80	sub->evt.event = htohl(event, sub->swap);
	81	sub->evt.found_lower = htohl(found_lower, sub->swap);
	82	sub->evt.found_upper = htohl(found_upper, sub->swap);
	83	sub->evt.port.ref = htohl(port_ref, sub->swap);
	84	sub->evt.port.node = htohl(node, sub->swap);
a62fbcce YX	85	tipc_conn_sendmsg(tn->topsrv, subscriber->conid, NULL,
a62fbcce YX	86	msg_sect.iov_base, msg_sect.iov_len);
b97bf3fd PL	87	}
	88
	89	/**
57f1d186 YX	90	* tipc_subscrp_check_overlap - test for subscription overlap with the
57f1d186 YX	91	* given values
b97bf3fd PL	92	*
	93	* Returns 1 if there is overlap, otherwise 0.
	94	*/
57f1d186 YX	95	int tipc_subscrp_check_overlap(struct tipc_subscription *sub, u32 found_lower,
57f1d186 YX	96	u32 found_upper)
b97bf3fd PL	97	{
	98	if (found_lower < sub->seq.lower)
	99	found_lower = sub->seq.lower;
	100	if (found_upper > sub->seq.upper)
	101	found_upper = sub->seq.upper;
	102	if (found_lower > found_upper)
	103	return 0;
	104	return 1;
	105	}
	106
57f1d186 YX	107	void tipc_subscrp_report_overlap(struct tipc_subscription *sub, u32 found_lower,
	108	u32 found_upper, u32 event, u32 port_ref,
	109	u32 node, int must)
b97bf3fd	110	{
57f1d186	111	if (!tipc_subscrp_check_overlap(sub, found_lower, found_upper))
b97bf3fd	112	return;
eb409460	113	if (!must && !(sub->filter & TIPC_SUB_PORTS))
b97bf3fd	114	return;
e15f8804	115
57f1d186 YX	116	tipc_subscrp_send_event(sub, found_lower, found_upper, event, port_ref,
57f1d186 YX	117	node);
b97bf3fd PL	118	}
b97bf3fd PL	119
57f1d186	120	static void tipc_subscrp_timeout(unsigned long data)
b97bf3fd	121	{
2f55c437	122	struct tipc_subscription sub = (struct tipc_subscription )data;
13a2e898	123	struct tipc_subscriber *subscriber = sub->subscriber;
28353e7f AS	124
28353e7f AS	125	/* Notify subscriber of timeout */
57f1d186 YX	126	tipc_subscrp_send_event(sub, sub->evt.s.seq.lower, sub->evt.s.seq.upper,
57f1d186 YX	127	TIPC_SUBSCR_TIMEOUT, 0, 0);
28353e7f	128
00bc00a9 YX	129	spin_lock_bh(&subscriber->lock);
	130	tipc_subscrp_delete(sub);
	131	spin_unlock_bh(&subscriber->lock);
	132
	133	tipc_subscrb_put(subscriber);
b97bf3fd PL	134	}
b97bf3fd PL	135
00bc00a9	136	static void tipc_subscrb_kref_release(struct kref *kref)
eb409460	137	{
00bc00a9 YX	138	struct tipc_subscriber *subcriber = container_of(kref,
00bc00a9 YX	139	struct tipc_subscriber, kref);
a62fbcce	140
00bc00a9 YX	141	kfree(subcriber);
	142	}
	143
	144	static void tipc_subscrb_put(struct tipc_subscriber *subscriber)
	145	{
	146	kref_put(&subscriber->kref, tipc_subscrb_kref_release);
	147	}
	148
	149	static void tipc_subscrb_get(struct tipc_subscriber *subscriber)
	150	{
	151	kref_get(&subscriber->kref);
eb409460 LC	152	}
eb409460 LC	153
1b764828 YX	154	static struct tipc_subscriber *tipc_subscrb_create(int conid)
	155	{
	156	struct tipc_subscriber *subscriber;
	157
	158	subscriber = kzalloc(sizeof(*subscriber), GFP_ATOMIC);
	159	if (!subscriber) {
	160	pr_warn("Subscriber rejected, no memory\n");
	161	return NULL;
	162	}
00bc00a9	163	kref_init(&subscriber->kref);
1b764828 YX	164	INIT_LIST_HEAD(&subscriber->subscrp_list);
	165	subscriber->conid = conid;
	166	spin_lock_init(&subscriber->lock);
	167
	168	return subscriber;
	169	}
	170
57f1d186	171	static void tipc_subscrb_delete(struct tipc_subscriber *subscriber)
13a2e898	172	{
00bc00a9	173	struct tipc_subscription sub, temp;
b97bf3fd	174
13a2e898	175	spin_lock_bh(&subscriber->lock);
b97bf3fd	176	/* Destroy any existing subscriptions for subscriber */
00bc00a9	177	list_for_each_entry_safe(sub, temp, &subscriber->subscrp_list,
57f1d186	178	subscrp_list) {
00bc00a9 YX	179	if (del_timer(&sub->timer)) {
	180	tipc_subscrp_delete(sub);
	181	tipc_subscrb_put(subscriber);
b97bf3fd	182	}
b97bf3fd	183	}
13a2e898	184	spin_unlock_bh(&subscriber->lock);
28353e7f	185
00bc00a9 YX	186	tipc_subscrb_put(subscriber);
	187	}
	188
	189	static void tipc_subscrp_delete(struct tipc_subscription *sub)
	190	{
	191	struct tipc_net *tn = net_generic(sub->net, tipc_net_id);
	192
	193	tipc_nametbl_unsubscribe(sub);
	194	list_del(&sub->subscrp_list);
	195	kfree(sub);
	196	atomic_dec(&tn->subscription_count);
b97bf3fd PL	197	}
b97bf3fd PL	198
57f1d186 YX	199	static void tipc_subscrp_cancel(struct tipc_subscr *s,
57f1d186 YX	200	struct tipc_subscriber *subscriber)
eb409460	201	{
00bc00a9	202	struct tipc_subscription sub, temp;
eb409460	203
a13683f2	204	spin_lock_bh(&subscriber->lock);
eb409460	205	/* Find first matching subscription, exit if not found */
00bc00a9	206	list_for_each_entry_safe(sub, temp, &subscriber->subscrp_list,
57f1d186	207	subscrp_list) {
db5a753b	208	if (!memcmp(s, &sub->evt.s, sizeof(struct tipc_subscr))) {
00bc00a9 YX	209	if (del_timer(&sub->timer)) {
	210	tipc_subscrp_delete(sub);
	211	tipc_subscrb_put(subscriber);
	212	}
db5a753b NH	213	break;
db5a753b NH	214	}
eb409460	215	}
a13683f2	216	spin_unlock_bh(&subscriber->lock);
eb409460 LC	217	}
eb409460 LC	218
57f1d186 YX	219	static int tipc_subscrp_create(struct net net, struct tipc_subscr s,
	220	struct tipc_subscriber *subscriber,
	221	struct tipc_subscription **sub_p)
a62fbcce YX	222	{
a62fbcce YX	223	struct tipc_net *tn = net_generic(net, tipc_net_id);
fead3909	224	struct tipc_subscription *sub;
db5a753b NH	225	int swap;
	226
	227	/* Determine subscriber's endianness */
db5a753b	228	swap = !(s->filter & (TIPC_SUB_PORTS \| TIPC_SUB_SERVICE));
eb409460 LC	229
eb409460 LC	230	/* Detect & process a subscription cancellation request */
db5a753b NH	231	if (s->filter & htohl(TIPC_SUB_CANCEL, swap)) {
db5a753b NH	232	s->filter &= ~htohl(TIPC_SUB_CANCEL, swap);
57f1d186	233	tipc_subscrp_cancel(s, subscriber);
a5d0e7c0	234	return 0;
eb409460 LC	235	}
eb409460 LC	236
b97bf3fd	237	/* Refuse subscription if global limit exceeded */
a62fbcce	238	if (atomic_read(&tn->subscription_count) >= TIPC_MAX_SUBSCRIPTIONS) {
2cf8aa19	239	pr_warn("Subscription rejected, limit reached (%u)\n",
34f256cc	240	TIPC_MAX_SUBSCRIPTIONS);
a5d0e7c0	241	return -EINVAL;
b97bf3fd PL	242	}
	243
	244	/* Allocate subscription object */
28353e7f	245	sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
a10bd924	246	if (!sub) {
2cf8aa19	247	pr_warn("Subscription rejected, no memory\n");
a5d0e7c0	248	return -ENOMEM;
b97bf3fd PL	249	}
b97bf3fd PL	250
b97bf3fd	251	/* Initialize subscription object */
4ac1c8d0	252	sub->net = net;
db5a753b NH	253	sub->seq.type = htohl(s->seq.type, swap);
	254	sub->seq.lower = htohl(s->seq.lower, swap);
	255	sub->seq.upper = htohl(s->seq.upper, swap);
2f55c437	256	sub->timeout = msecs_to_jiffies(htohl(s->timeout, swap));
db5a753b	257	sub->filter = htohl(s->filter, swap);
8c974438 NH	258	if ((!(sub->filter & TIPC_SUB_PORTS) ==
8c974438 NH	259	!(sub->filter & TIPC_SUB_SERVICE)) \|\|
f64f9e71	260	(sub->seq.lower > sub->seq.upper)) {
2cf8aa19	261	pr_warn("Subscription rejected, illegal request\n");
b97bf3fd	262	kfree(sub);
a5d0e7c0	263	return -EINVAL;
b97bf3fd	264	}
a13683f2	265	spin_lock_bh(&subscriber->lock);
57f1d186	266	list_add(&sub->subscrp_list, &subscriber->subscrp_list);
a13683f2	267	spin_unlock_bh(&subscriber->lock);
13a2e898	268	sub->subscriber = subscriber;
db5a753b	269	sub->swap = swap;
57f1d186	270	memcpy(&sub->evt.s, s, sizeof(*s));
a62fbcce	271	atomic_inc(&tn->subscription_count);
00bc00a9 YX	272	setup_timer(&sub->timer, tipc_subscrp_timeout, (unsigned long)sub);
	273	if (sub->timeout != TIPC_WAIT_FOREVER)
	274	sub->timeout += jiffies;
	275	if (!mod_timer(&sub->timer, sub->timeout))
	276	tipc_subscrb_get(subscriber);
a5d0e7c0 EH	277	*sub_p = sub;
a5d0e7c0 EH	278	return 0;
b97bf3fd PL	279	}
b97bf3fd PL	280
13a2e898	281	/* Handle one termination request for the subscriber */
57f1d186	282	static void tipc_subscrb_shutdown_cb(int conid, void *usr_data)
b97bf3fd	283	{
57f1d186	284	tipc_subscrb_delete((struct tipc_subscriber *)usr_data);
b97bf3fd PL	285	}
b97bf3fd PL	286
13a2e898	287	/* Handle one request to create a new subscription for the subscriber */
57f1d186 YX	288	static void tipc_subscrb_rcv_cb(struct net *net, int conid,
	289	struct sockaddr_tipc addr, void usr_data,
	290	void *buf, size_t len)
b97bf3fd	291	{
13a2e898	292	struct tipc_subscriber *subscriber = usr_data;
a5d0e7c0	293	struct tipc_subscription *sub = NULL;
7fe8097c	294	struct tipc_net *tn = net_generic(net, tipc_net_id);
28353e7f	295
57f1d186	296	tipc_subscrp_create(net, (struct tipc_subscr *)buf, subscriber, &sub);
13a2e898 YX	297	if (sub)
13a2e898 YX	298	tipc_nametbl_subscribe(sub);
7fe8097c EH	299	else
7fe8097c EH	300	tipc_conn_terminate(tn->topsrv, subscriber->conid);
b97bf3fd PL	301	}
b97bf3fd PL	302
13a2e898	303	/* Handle one request to establish a new subscriber */
57f1d186	304	static void *tipc_subscrb_connect_cb(int conid)
b97bf3fd	305	{
1b764828	306	return (void *)tipc_subscrb_create(conid);
b97bf3fd PL	307	}
b97bf3fd PL	308
57f1d186	309	int tipc_topsrv_start(struct net *net)
b97bf3fd	310	{
a62fbcce YX	311	struct tipc_net *tn = net_generic(net, tipc_net_id);
	312	const char name[] = "topology_server";
	313	struct tipc_server *topsrv;
	314	struct sockaddr_tipc *saddr;
	315
	316	saddr = kzalloc(sizeof(*saddr), GFP_ATOMIC);
	317	if (!saddr)
	318	return -ENOMEM;
	319	saddr->family = AF_TIPC;
	320	saddr->addrtype = TIPC_ADDR_NAMESEQ;
	321	saddr->addr.nameseq.type = TIPC_TOP_SRV;
	322	saddr->addr.nameseq.lower = TIPC_TOP_SRV;
	323	saddr->addr.nameseq.upper = TIPC_TOP_SRV;
	324	saddr->scope = TIPC_NODE_SCOPE;
	325
	326	topsrv = kzalloc(sizeof(*topsrv), GFP_ATOMIC);
	327	if (!topsrv) {
	328	kfree(saddr);
	329	return -ENOMEM;
	330	}
	331	topsrv->net = net;
	332	topsrv->saddr = saddr;
	333	topsrv->imp = TIPC_CRITICAL_IMPORTANCE;
	334	topsrv->type = SOCK_SEQPACKET;
	335	topsrv->max_rcvbuf_size = sizeof(struct tipc_subscr);
57f1d186 YX	336	topsrv->tipc_conn_recvmsg = tipc_subscrb_rcv_cb;
	337	topsrv->tipc_conn_new = tipc_subscrb_connect_cb;
	338	topsrv->tipc_conn_shutdown = tipc_subscrb_shutdown_cb;
a62fbcce YX	339
	340	strncpy(topsrv->name, name, strlen(name) + 1);
	341	tn->topsrv = topsrv;
	342	atomic_set(&tn->subscription_count, 0);
	343
	344	return tipc_server_start(topsrv);
b97bf3fd PL	345	}
b97bf3fd PL	346
57f1d186	347	void tipc_topsrv_stop(struct net *net)
b97bf3fd	348	{
a62fbcce YX	349	struct tipc_net *tn = net_generic(net, tipc_net_id);
	350	struct tipc_server *topsrv = tn->topsrv;
	351
	352	tipc_server_stop(topsrv);
	353	kfree(topsrv->saddr);
	354	kfree(topsrv);
b97bf3fd	355	}