[mirror_ubuntu-artful-kernel.git] / net / tipc / node.c

/*
 * net/tipc/node.c: TIPC node management routines
 *
 * Copyright (c) 2000-2006, 2012 Ericsson AB
 * Copyright (c) 2005-2006, 2010-2014, 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 "config.h"
#include "node.h"
#include "name_distr.h"

#define NODE_HTABLE_SIZE 512

static void node_lost_contact(struct tipc_node *n_ptr);
static void node_established_contact(struct tipc_node *n_ptr);

static struct hlist_head node_htable[NODE_HTABLE_SIZE];
LIST_HEAD(tipc_node_list);
static u32 tipc_num_nodes;
static u32 tipc_num_links;
static DEFINE_SPINLOCK(node_list_lock);

/*
 * A trivial power-of-two bitmask technique is used for speed, since this
 * operation is done for every incoming TIPC packet. The number of hash table
 * entries has been chosen so that no hash chain exceeds 8 nodes and will
 * usually be much smaller (typically only a single node).
 */
static unsigned int tipc_hashfn(u32 addr)
{
	return addr & (NODE_HTABLE_SIZE - 1);
}

/*
 * tipc_node_find - locate specified node object, if it exists
 */
struct tipc_node *tipc_node_find(u32 addr)
{
	struct tipc_node *node;

	if (unlikely(!in_own_cluster_exact(addr)))
		return NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(node, &node_htable[tipc_hashfn(addr)], hash) {
		if (node->addr == addr) {
			rcu_read_unlock();
			return node;
		}
	}
	rcu_read_unlock();
	return NULL;
}

struct tipc_node *tipc_node_create(u32 addr)
{
	struct tipc_node *n_ptr, *temp_node;

	spin_lock_bh(&node_list_lock);

	n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
	if (!n_ptr) {
		spin_unlock_bh(&node_list_lock);
		pr_warn("Node creation failed, no memory\n");
		return NULL;
	}

	n_ptr->addr = addr;
	spin_lock_init(&n_ptr->lock);
	INIT_HLIST_NODE(&n_ptr->hash);
	INIT_LIST_HEAD(&n_ptr->list);
	INIT_LIST_HEAD(&n_ptr->nsub);

	hlist_add_head_rcu(&n_ptr->hash, &node_htable[tipc_hashfn(addr)]);

	list_for_each_entry_rcu(temp_node, &tipc_node_list, list) {
		if (n_ptr->addr < temp_node->addr)
			break;
	}
	list_add_tail_rcu(&n_ptr->list, &temp_node->list);
	n_ptr->block_setup = WAIT_PEER_DOWN;
	n_ptr->signature = INVALID_NODE_SIG;

	tipc_num_nodes++;

	spin_unlock_bh(&node_list_lock);
	return n_ptr;
}

static void tipc_node_delete(struct tipc_node *n_ptr)
{
	list_del_rcu(&n_ptr->list);
	hlist_del_rcu(&n_ptr->hash);
	kfree_rcu(n_ptr, rcu);

	tipc_num_nodes--;
}

void tipc_node_stop(void)
{
	struct tipc_node *node, *t_node;

	spin_lock_bh(&node_list_lock);
	list_for_each_entry_safe(node, t_node, &tipc_node_list, list)
		tipc_node_delete(node);
	spin_unlock_bh(&node_list_lock);
}

/**
 * tipc_node_link_up - handle addition of link
 *
 * Link becomes active (alone or shared) or standby, depending on its priority.
 */
void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
{
	struct tipc_link **active = &n_ptr->active_links[0];

	n_ptr->working_links++;

	pr_info("Established link <%s> on network plane %c\n",
		l_ptr->name, l_ptr->b_ptr->net_plane);

	if (!active[0]) {
		active[0] = active[1] = l_ptr;
		node_established_contact(n_ptr);
		return;
	}
	if (l_ptr->priority < active[0]->priority) {
		pr_info("New link <%s> becomes standby\n", l_ptr->name);
		return;
	}
	tipc_link_dup_queue_xmit(active[0], l_ptr);
	if (l_ptr->priority == active[0]->priority) {
		active[0] = l_ptr;
		return;
	}
	pr_info("Old link <%s> becomes standby\n", active[0]->name);
	if (active[1] != active[0])
		pr_info("Old link <%s> becomes standby\n", active[1]->name);
	active[0] = active[1] = l_ptr;
}

/**
 * node_select_active_links - select active link
 */
static void node_select_active_links(struct tipc_node *n_ptr)
{
	struct tipc_link **active = &n_ptr->active_links[0];
	u32 i;
	u32 highest_prio = 0;

	active[0] = active[1] = NULL;

	for (i = 0; i < MAX_BEARERS; i++) {
		struct tipc_link *l_ptr = n_ptr->links[i];

		if (!l_ptr || !tipc_link_is_up(l_ptr) ||
		    (l_ptr->priority < highest_prio))
			continue;

		if (l_ptr->priority > highest_prio) {
			highest_prio = l_ptr->priority;
			active[0] = active[1] = l_ptr;
		} else {
			active[1] = l_ptr;
		}
	}
}

/**
 * tipc_node_link_down - handle loss of link
 */
void tipc_node_link_down(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
{
	struct tipc_link **active;

	n_ptr->working_links--;

	if (!tipc_link_is_active(l_ptr)) {
		pr_info("Lost standby link <%s> on network plane %c\n",
			l_ptr->name, l_ptr->b_ptr->net_plane);
		return;
	}
	pr_info("Lost link <%s> on network plane %c\n",
		l_ptr->name, l_ptr->b_ptr->net_plane);

	active = &n_ptr->active_links[0];
	if (active[0] == l_ptr)
		active[0] = active[1];
	if (active[1] == l_ptr)
		active[1] = active[0];
	if (active[0] == l_ptr)
		node_select_active_links(n_ptr);
	if (tipc_node_is_up(n_ptr))
		tipc_link_failover_send_queue(l_ptr);
	else
		node_lost_contact(n_ptr);
}

int tipc_node_active_links(struct tipc_node *n_ptr)
{
	return n_ptr->active_links[0] != NULL;
}

int tipc_node_is_up(struct tipc_node *n_ptr)
{
	return tipc_node_active_links(n_ptr);
}

void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
{
	n_ptr->links[l_ptr->b_ptr->identity] = l_ptr;
	spin_lock_bh(&node_list_lock);
	tipc_num_links++;
	spin_unlock_bh(&node_list_lock);
	n_ptr->link_cnt++;
}

void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
{
	int i;

	for (i = 0; i < MAX_BEARERS; i++) {
		if (l_ptr != n_ptr->links[i])
			continue;
		n_ptr->links[i] = NULL;
		spin_lock_bh(&node_list_lock);
		tipc_num_links--;
		spin_unlock_bh(&node_list_lock);
		n_ptr->link_cnt--;
	}
}

static void node_established_contact(struct tipc_node *n_ptr)
{
	tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
	n_ptr->bclink.oos_state = 0;
	n_ptr->bclink.acked = tipc_bclink_get_last_sent();
	tipc_bclink_add_node(n_ptr->addr);
}

static void node_name_purge_complete(unsigned long node_addr)
{
	struct tipc_node *n_ptr;

	read_lock_bh(&tipc_net_lock);
	n_ptr = tipc_node_find(node_addr);
	if (n_ptr) {
		tipc_node_lock(n_ptr);
		n_ptr->block_setup &= ~WAIT_NAMES_GONE;
		tipc_node_unlock(n_ptr);
	}
	read_unlock_bh(&tipc_net_lock);
}

static void node_lost_contact(struct tipc_node *n_ptr)
{
	char addr_string[16];
	u32 i;

	pr_info("Lost contact with %s\n",
		tipc_addr_string_fill(addr_string, n_ptr->addr));

	/* Flush broadcast link info associated with lost node */
	if (n_ptr->bclink.recv_permitted) {
		kfree_skb_list(n_ptr->bclink.deferred_head);
		n_ptr->bclink.deferred_size = 0;

		if (n_ptr->bclink.reasm_head) {
			kfree_skb(n_ptr->bclink.reasm_head);
			n_ptr->bclink.reasm_head = NULL;
			n_ptr->bclink.reasm_tail = NULL;
		}

		tipc_bclink_remove_node(n_ptr->addr);
		tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ);

		n_ptr->bclink.recv_permitted = false;
	}

	/* Abort link changeover */
	for (i = 0; i < MAX_BEARERS; i++) {
		struct tipc_link *l_ptr = n_ptr->links[i];
		if (!l_ptr)
			continue;
		l_ptr->reset_checkpoint = l_ptr->next_in_no;
		l_ptr->exp_msg_count = 0;
		tipc_link_reset_fragments(l_ptr);
	}

	/* Notify subscribers */
	tipc_nodesub_notify(n_ptr);

	/* Prevent re-contact with node until cleanup is done */
	n_ptr->block_setup = WAIT_PEER_DOWN | WAIT_NAMES_GONE;
	tipc_k_signal((Handler)node_name_purge_complete, n_ptr->addr);
}

struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
{
	u32 domain;
	struct sk_buff *buf;
	struct tipc_node *n_ptr;
	struct tipc_node_info node_info;
	u32 payload_size;

	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

	domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
	if (!tipc_addr_domain_valid(domain))
		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
						   " (network address)");

	spin_lock_bh(&node_list_lock);
	if (!tipc_num_nodes) {
		spin_unlock_bh(&node_list_lock);
		return tipc_cfg_reply_none();
	}

	/* For now, get space for all other nodes */
	payload_size = TLV_SPACE(sizeof(node_info)) * tipc_num_nodes;
	if (payload_size > 32768u) {
		spin_unlock_bh(&node_list_lock);
		return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
						   " (too many nodes)");
	}
	spin_unlock_bh(&node_list_lock);

	buf = tipc_cfg_reply_alloc(payload_size);
	if (!buf)
		return NULL;

	/* Add TLVs for all nodes in scope */
	rcu_read_lock();
	list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
		if (!tipc_in_scope(domain, n_ptr->addr))
			continue;
		node_info.addr = htonl(n_ptr->addr);
		node_info.up = htonl(tipc_node_is_up(n_ptr));
		tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
				    &node_info, sizeof(node_info));
	}
	rcu_read_unlock();
	return buf;
}

struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
{
	u32 domain;
	struct sk_buff *buf;
	struct tipc_node *n_ptr;
	struct tipc_link_info link_info;
	u32 payload_size;

	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

	domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
	if (!tipc_addr_domain_valid(domain))
		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
						   " (network address)");

	if (!tipc_own_addr)
		return tipc_cfg_reply_none();

	spin_lock_bh(&node_list_lock);
	/* Get space for all unicast links + broadcast link */
	payload_size = TLV_SPACE((sizeof(link_info)) * (tipc_num_links + 1));
	if (payload_size > 32768u) {
		spin_unlock_bh(&node_list_lock);
		return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
						   " (too many links)");
	}
	spin_unlock_bh(&node_list_lock);

	buf = tipc_cfg_reply_alloc(payload_size);
	if (!buf)
		return NULL;

	/* Add TLV for broadcast link */
	link_info.dest = htonl(tipc_cluster_mask(tipc_own_addr));
	link_info.up = htonl(1);
	strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME);
	tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));

	/* Add TLVs for any other links in scope */
	rcu_read_lock();
	list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
		u32 i;

		if (!tipc_in_scope(domain, n_ptr->addr))
			continue;
		tipc_node_lock(n_ptr);
		for (i = 0; i < MAX_BEARERS; i++) {
			if (!n_ptr->links[i])
				continue;
			link_info.dest = htonl(n_ptr->addr);
			link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
			strcpy(link_info.str, n_ptr->links[i]->name);
			tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
					    &link_info, sizeof(link_info));
		}
		tipc_node_unlock(n_ptr);
	}
	rcu_read_unlock();
	return buf;
}
Commit	Line	Data
b97bf3fd PL	1	/*
b97bf3fd PL	2	* net/tipc/node.c: TIPC node management routines
c4307285	3	*
c64f7a6a	4	* Copyright (c) 2000-2006, 2012 Ericsson AB
46651c59	5	* Copyright (c) 2005-2006, 2010-2014, 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"
	38	#include "config.h"
	39	#include "node.h"
b97bf3fd	40	#include "name_distr.h"
b97bf3fd	41
a635b46b AS	42	#define NODE_HTABLE_SIZE 512
a635b46b AS	43
6c00055a DM	44	static void node_lost_contact(struct tipc_node *n_ptr);
6c00055a DM	45	static void node_established_contact(struct tipc_node *n_ptr);
b97bf3fd	46
672d99e1 AS	47	static struct hlist_head node_htable[NODE_HTABLE_SIZE];
	48	LIST_HEAD(tipc_node_list);
	49	static u32 tipc_num_nodes;
dde20266	50	static u32 tipc_num_links;
46651c59	51	static DEFINE_SPINLOCK(node_list_lock);
34e46258	52
a635b46b AS	53	/*
	54	* A trivial power-of-two bitmask technique is used for speed, since this
	55	* operation is done for every incoming TIPC packet. The number of hash table
	56	* entries has been chosen so that no hash chain exceeds 8 nodes and will
	57	* usually be much smaller (typically only a single node).
	58	*/
872f24db	59	static unsigned int tipc_hashfn(u32 addr)
a635b46b AS	60	{
	61	return addr & (NODE_HTABLE_SIZE - 1);
	62	}
	63
1ec2bb08	64	/*
672d99e1 AS	65	* tipc_node_find - locate specified node object, if it exists
672d99e1 AS	66	*/
672d99e1 AS	67	struct tipc_node *tipc_node_find(u32 addr)
	68	{
	69	struct tipc_node *node;
672d99e1	70
336ebf5b	71	if (unlikely(!in_own_cluster_exact(addr)))
672d99e1 AS	72	return NULL;
672d99e1 AS	73
6c7a762e YX	74	rcu_read_lock();
6c7a762e YX	75	hlist_for_each_entry_rcu(node, &node_htable[tipc_hashfn(addr)], hash) {
46651c59	76	if (node->addr == addr) {
6c7a762e	77	rcu_read_unlock();
672d99e1	78	return node;
46651c59	79	}
672d99e1	80	}
6c7a762e	81	rcu_read_unlock();
672d99e1 AS	82	return NULL;
	83	}
	84
6c00055a	85	struct tipc_node *tipc_node_create(u32 addr)
b97bf3fd	86	{
672d99e1	87	struct tipc_node n_ptr, temp_node;
b97bf3fd	88
46651c59	89	spin_lock_bh(&node_list_lock);
2ecb0924	90
5af54792	91	n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
a10bd924	92	if (!n_ptr) {
46651c59	93	spin_unlock_bh(&node_list_lock);
2cf8aa19	94	pr_warn("Node creation failed, no memory\n");
a10bd924 AS	95	return NULL;
	96	}
	97
a10bd924	98	n_ptr->addr = addr;
51a8e4de	99	spin_lock_init(&n_ptr->lock);
672d99e1 AS	100	INIT_HLIST_NODE(&n_ptr->hash);
672d99e1 AS	101	INIT_LIST_HEAD(&n_ptr->list);
a10bd924	102	INIT_LIST_HEAD(&n_ptr->nsub);
8f92df6a	103
6c7a762e	104	hlist_add_head_rcu(&n_ptr->hash, &node_htable[tipc_hashfn(addr)]);
672d99e1	105
6c7a762e	106	list_for_each_entry_rcu(temp_node, &tipc_node_list, list) {
672d99e1 AS	107	if (n_ptr->addr < temp_node->addr)
	108	break;
	109	}
6c7a762e	110	list_add_tail_rcu(&n_ptr->list, &temp_node->list);
b4b56102	111	n_ptr->block_setup = WAIT_PEER_DOWN;
fc0eea69	112	n_ptr->signature = INVALID_NODE_SIG;
672d99e1 AS	113
672d99e1 AS	114	tipc_num_nodes++;
a10bd924	115
46651c59	116	spin_unlock_bh(&node_list_lock);
b97bf3fd PL	117	return n_ptr;
	118	}
	119
46651c59	120	static void tipc_node_delete(struct tipc_node *n_ptr)
b97bf3fd	121	{
6c7a762e YX	122	list_del_rcu(&n_ptr->list);
	123	hlist_del_rcu(&n_ptr->hash);
	124	kfree_rcu(n_ptr, rcu);
8f92df6a	125
672d99e1	126	tipc_num_nodes--;
b97bf3fd PL	127	}
b97bf3fd PL	128
46651c59 YX	129	void tipc_node_stop(void)
	130	{
	131	struct tipc_node node, t_node;
	132
	133	spin_lock_bh(&node_list_lock);
	134	list_for_each_entry_safe(node, t_node, &tipc_node_list, list)
	135	tipc_node_delete(node);
	136	spin_unlock_bh(&node_list_lock);
	137	}
	138
b97bf3fd	139	/**
4323add6	140	* tipc_node_link_up - handle addition of link
c4307285	141	*
b97bf3fd PL	142	* Link becomes active (alone or shared) or standby, depending on its priority.
b97bf3fd PL	143	*/
a18c4bc3	144	void tipc_node_link_up(struct tipc_node n_ptr, struct tipc_link l_ptr)
b97bf3fd	145	{
a18c4bc3	146	struct tipc_link **active = &n_ptr->active_links[0];
b97bf3fd	147
5392d646 AS	148	n_ptr->working_links++;
5392d646 AS	149
2cf8aa19 EH	150	pr_info("Established link <%s> on network plane %c\n",
2cf8aa19 EH	151	l_ptr->name, l_ptr->b_ptr->net_plane);
c4307285	152
b97bf3fd	153	if (!active[0]) {
b97bf3fd PL	154	active[0] = active[1] = l_ptr;
	155	node_established_contact(n_ptr);
	156	return;
	157	}
c4307285	158	if (l_ptr->priority < active[0]->priority) {
2cf8aa19	159	pr_info("New link <%s> becomes standby\n", l_ptr->name);
b97bf3fd PL	160	return;
b97bf3fd PL	161	}
247f0f3c	162	tipc_link_dup_queue_xmit(active[0], l_ptr);
c4307285	163	if (l_ptr->priority == active[0]->priority) {
b97bf3fd PL	164	active[0] = l_ptr;
	165	return;
	166	}
2cf8aa19	167	pr_info("Old link <%s> becomes standby\n", active[0]->name);
a10bd924	168	if (active[1] != active[0])
2cf8aa19	169	pr_info("Old link <%s> becomes standby\n", active[1]->name);
b97bf3fd PL	170	active[0] = active[1] = l_ptr;
	171	}
	172
	173	/**
	174	* node_select_active_links - select active link
	175	*/
6c00055a	176	static void node_select_active_links(struct tipc_node *n_ptr)
b97bf3fd	177	{
a18c4bc3	178	struct tipc_link **active = &n_ptr->active_links[0];
b97bf3fd PL	179	u32 i;
	180	u32 highest_prio = 0;
	181
c4307285	182	active[0] = active[1] = NULL;
b97bf3fd PL	183
b97bf3fd PL	184	for (i = 0; i < MAX_BEARERS; i++) {
a18c4bc3	185	struct tipc_link *l_ptr = n_ptr->links[i];
b97bf3fd	186
4323add6	187	if (!l_ptr \|\| !tipc_link_is_up(l_ptr) \|\|
b97bf3fd PL	188	(l_ptr->priority < highest_prio))
	189	continue;
	190
	191	if (l_ptr->priority > highest_prio) {
c4307285	192	highest_prio = l_ptr->priority;
b97bf3fd PL	193	active[0] = active[1] = l_ptr;
	194	} else {
	195	active[1] = l_ptr;
	196	}
	197	}
	198	}
	199
	200	/**
4323add6	201	* tipc_node_link_down - handle loss of link
b97bf3fd	202	*/
a18c4bc3	203	void tipc_node_link_down(struct tipc_node n_ptr, struct tipc_link l_ptr)
b97bf3fd	204	{
a18c4bc3	205	struct tipc_link **active;
b97bf3fd	206
5392d646 AS	207	n_ptr->working_links--;
5392d646 AS	208
4323add6	209	if (!tipc_link_is_active(l_ptr)) {
2cf8aa19 EH	210	pr_info("Lost standby link <%s> on network plane %c\n",
2cf8aa19 EH	211	l_ptr->name, l_ptr->b_ptr->net_plane);
b97bf3fd PL	212	return;
b97bf3fd PL	213	}
2cf8aa19	214	pr_info("Lost link <%s> on network plane %c\n",
b97bf3fd PL	215	l_ptr->name, l_ptr->b_ptr->net_plane);
	216
	217	active = &n_ptr->active_links[0];
	218	if (active[0] == l_ptr)
	219	active[0] = active[1];
	220	if (active[1] == l_ptr)
	221	active[1] = active[0];
	222	if (active[0] == l_ptr)
	223	node_select_active_links(n_ptr);
c4307285	224	if (tipc_node_is_up(n_ptr))
170b3927	225	tipc_link_failover_send_queue(l_ptr);
c4307285	226	else
b97bf3fd PL	227	node_lost_contact(n_ptr);
	228	}
	229
8f19afb2	230	int tipc_node_active_links(struct tipc_node *n_ptr)
b97bf3fd	231	{
76ae0d71	232	return n_ptr->active_links[0] != NULL;
b97bf3fd PL	233	}
b97bf3fd PL	234
6c00055a	235	int tipc_node_is_up(struct tipc_node *n_ptr)
b97bf3fd	236	{
8f19afb2	237	return tipc_node_active_links(n_ptr);
b97bf3fd PL	238	}
b97bf3fd PL	239
a18c4bc3	240	void tipc_node_attach_link(struct tipc_node n_ptr, struct tipc_link l_ptr)
b97bf3fd	241	{
37b9c08a	242	n_ptr->links[l_ptr->b_ptr->identity] = l_ptr;
dde20266 YX	243	spin_lock_bh(&node_list_lock);
	244	tipc_num_links++;
	245	spin_unlock_bh(&node_list_lock);
37b9c08a	246	n_ptr->link_cnt++;
b97bf3fd PL	247	}
b97bf3fd PL	248
a18c4bc3	249	void tipc_node_detach_link(struct tipc_node n_ptr, struct tipc_link l_ptr)
b97bf3fd	250	{
7d33939f JPM	251	int i;
	252
	253	for (i = 0; i < MAX_BEARERS; i++) {
074bb43e JPM	254	if (l_ptr != n_ptr->links[i])
	255	continue;
	256	n_ptr->links[i] = NULL;
dde20266 YX	257	spin_lock_bh(&node_list_lock);
	258	tipc_num_links--;
	259	spin_unlock_bh(&node_list_lock);
074bb43e	260	n_ptr->link_cnt--;
7d33939f	261	}
b97bf3fd PL	262	}
b97bf3fd PL	263
6c00055a	264	static void node_established_contact(struct tipc_node *n_ptr)
b97bf3fd	265	{
51a8e4de	266	tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
c64f7a6a	267	n_ptr->bclink.oos_state = 0;
818f4da5 YX	268	n_ptr->bclink.acked = tipc_bclink_get_last_sent();
818f4da5 YX	269	tipc_bclink_add_node(n_ptr->addr);
b97bf3fd PL	270	}
b97bf3fd PL	271
b4b56102	272	static void node_name_purge_complete(unsigned long node_addr)
5a68d5ee AS	273	{
	274	struct tipc_node *n_ptr;
	275
	276	read_lock_bh(&tipc_net_lock);
	277	n_ptr = tipc_node_find(node_addr);
	278	if (n_ptr) {
	279	tipc_node_lock(n_ptr);
b4b56102	280	n_ptr->block_setup &= ~WAIT_NAMES_GONE;
5a68d5ee AS	281	tipc_node_unlock(n_ptr);
	282	}
	283	read_unlock_bh(&tipc_net_lock);
	284	}
	285
6c00055a	286	static void node_lost_contact(struct tipc_node *n_ptr)
b97bf3fd	287	{
b97bf3fd PL	288	char addr_string[16];
	289	u32 i;
	290
2cf8aa19 EH	291	pr_info("Lost contact with %s\n",
2cf8aa19 EH	292	tipc_addr_string_fill(addr_string, n_ptr->addr));
c5bd4d85 AS	293
c5bd4d85 AS	294	/* Flush broadcast link info associated with lost node */
389dd9bc	295	if (n_ptr->bclink.recv_permitted) {
d77b3831	296	kfree_skb_list(n_ptr->bclink.deferred_head);
7a54d4a9	297	n_ptr->bclink.deferred_size = 0;
c5bd4d85	298
40ba3cdf EH	299	if (n_ptr->bclink.reasm_head) {
	300	kfree_skb(n_ptr->bclink.reasm_head);
	301	n_ptr->bclink.reasm_head = NULL;
	302	n_ptr->bclink.reasm_tail = NULL;
c5bd4d85 AS	303	}
c5bd4d85 AS	304
cd3decdf	305	tipc_bclink_remove_node(n_ptr->addr);
36559591	306	tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ);
b97bf3fd	307
389dd9bc	308	n_ptr->bclink.recv_permitted = false;
c5bd4d85	309	}
b97bf3fd PL	310
	311	/* Abort link changeover */
	312	for (i = 0; i < MAX_BEARERS; i++) {
a18c4bc3	313	struct tipc_link *l_ptr = n_ptr->links[i];
c4307285	314	if (!l_ptr)
b97bf3fd PL	315	continue;
	316	l_ptr->reset_checkpoint = l_ptr->next_in_no;
	317	l_ptr->exp_msg_count = 0;
4323add6	318	tipc_link_reset_fragments(l_ptr);
b97bf3fd PL	319	}
	320
	321	/* Notify subscribers */
f1379173	322	tipc_nodesub_notify(n_ptr);
5a68d5ee	323
b4b56102	324	/* Prevent re-contact with node until cleanup is done */
b4b56102 AS	325	n_ptr->block_setup = WAIT_PEER_DOWN \| WAIT_NAMES_GONE;
b4b56102 AS	326	tipc_k_signal((Handler)node_name_purge_complete, n_ptr->addr);
b97bf3fd PL	327	}
b97bf3fd PL	328
4323add6	329	struct sk_buff tipc_node_get_nodes(const void req_tlv_area, int req_tlv_space)
b97bf3fd PL	330	{
	331	u32 domain;
	332	struct sk_buff *buf;
6c00055a	333	struct tipc_node *n_ptr;
c4307285	334	struct tipc_node_info node_info;
ea13847b	335	u32 payload_size;
b97bf3fd PL	336
b97bf3fd PL	337	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
4323add6	338	return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
b97bf3fd	339
3e6c8cd5	340	domain = ntohl((__be32 )TLV_DATA(req_tlv_area));
4323add6 PL	341	if (!tipc_addr_domain_valid(domain))
	342	return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
	343	" (network address)");
b97bf3fd	344
46651c59	345	spin_lock_bh(&node_list_lock);
672d99e1	346	if (!tipc_num_nodes) {
46651c59	347	spin_unlock_bh(&node_list_lock);
c4307285	348	return tipc_cfg_reply_none();
1aad72d6	349	}
b97bf3fd	350
08c80e9a	351	/* For now, get space for all other nodes */
672d99e1	352	payload_size = TLV_SPACE(sizeof(node_info)) * tipc_num_nodes;
1aad72d6	353	if (payload_size > 32768u) {
46651c59	354	spin_unlock_bh(&node_list_lock);
ea13847b AS	355	return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
ea13847b AS	356	" (too many nodes)");
1aad72d6	357	}
2220646a YX	358	spin_unlock_bh(&node_list_lock);
2220646a YX	359
ea13847b	360	buf = tipc_cfg_reply_alloc(payload_size);
2220646a	361	if (!buf)
b97bf3fd PL	362	return NULL;
	363
	364	/* Add TLVs for all nodes in scope */
6c7a762e YX	365	rcu_read_lock();
6c7a762e YX	366	list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
672d99e1	367	if (!tipc_in_scope(domain, n_ptr->addr))
b97bf3fd	368	continue;
c4307285 YH	369	node_info.addr = htonl(n_ptr->addr);
	370	node_info.up = htonl(tipc_node_is_up(n_ptr));
	371	tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
4323add6	372	&node_info, sizeof(node_info));
b97bf3fd	373	}
6c7a762e	374	rcu_read_unlock();
b97bf3fd PL	375	return buf;
	376	}
	377
4323add6	378	struct sk_buff tipc_node_get_links(const void req_tlv_area, int req_tlv_space)
b97bf3fd PL	379	{
	380	u32 domain;
	381	struct sk_buff *buf;
6c00055a	382	struct tipc_node *n_ptr;
c4307285	383	struct tipc_link_info link_info;
ea13847b	384	u32 payload_size;
b97bf3fd PL	385
b97bf3fd PL	386	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
4323add6	387	return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
b97bf3fd	388
3e6c8cd5	389	domain = ntohl((__be32 )TLV_DATA(req_tlv_area));
4323add6 PL	390	if (!tipc_addr_domain_valid(domain))
	391	return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
	392	" (network address)");
b97bf3fd	393
b58343f9	394	if (!tipc_own_addr)
c4307285 YH	395	return tipc_cfg_reply_none();
c4307285 YH	396
46651c59	397	spin_lock_bh(&node_list_lock);
7a54d4a9	398	/* Get space for all unicast links + broadcast link */
dde20266	399	payload_size = TLV_SPACE((sizeof(link_info)) * (tipc_num_links + 1));
1aad72d6	400	if (payload_size > 32768u) {
46651c59	401	spin_unlock_bh(&node_list_lock);
ea13847b AS	402	return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
ea13847b AS	403	" (too many links)");
1aad72d6	404	}
dde20266 YX	405	spin_unlock_bh(&node_list_lock);
dde20266 YX	406
ea13847b	407	buf = tipc_cfg_reply_alloc(payload_size);
dde20266	408	if (!buf)
b97bf3fd PL	409	return NULL;
	410
	411	/* Add TLV for broadcast link */
a3796f89	412	link_info.dest = htonl(tipc_cluster_mask(tipc_own_addr));
c4307285	413	link_info.up = htonl(1);
4b704d59	414	strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME);
4323add6	415	tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
b97bf3fd PL	416
b97bf3fd PL	417	/* Add TLVs for any other links in scope */
6c7a762e YX	418	rcu_read_lock();
6c7a762e YX	419	list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
c4307285	420	u32 i;
b97bf3fd	421
672d99e1	422	if (!tipc_in_scope(domain, n_ptr->addr))
b97bf3fd	423	continue;
1aad72d6	424	tipc_node_lock(n_ptr);
c4307285 YH	425	for (i = 0; i < MAX_BEARERS; i++) {
	426	if (!n_ptr->links[i])
	427	continue;
	428	link_info.dest = htonl(n_ptr->addr);
	429	link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
	430	strcpy(link_info.str, n_ptr->links[i]->name);
	431	tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
4323add6	432	&link_info, sizeof(link_info));
c4307285	433	}
1aad72d6	434	tipc_node_unlock(n_ptr);
b97bf3fd	435	}
6c7a762e	436	rcu_read_unlock();
b97bf3fd PL	437	return buf;
b97bf3fd PL	438	}