Initial import

1 files changed, 1070 insertions, 0 deletions

diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
new file mode 100644
index 000000000..ab0ac62a1
--- /dev/null
+++ b/net/tipc/name_table.c
@@ -0,0 +1,1070 @@
+/*
+ * net/tipc/name_table.c: TIPC name table code
+ *
+ * Copyright (c) 2000-2006, 2014-2015, Ericsson AB
+ * Copyright (c) 2004-2008, 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 <net/sock.h>
+#include "core.h"
+#include "netlink.h"
+#include "name_table.h"
+#include "name_distr.h"
+#include "subscr.h"
+#include "bcast.h"
+#include "addr.h"
+#include <net/genetlink.h>
+
+#define TIPC_NAMETBL_SIZE 1024		/* must be a power of 2 */
+
+static const struct nla_policy
+tipc_nl_name_table_policy[TIPC_NLA_NAME_TABLE_MAX + 1] = {
+	[TIPC_NLA_NAME_TABLE_UNSPEC]	= { .type = NLA_UNSPEC },
+	[TIPC_NLA_NAME_TABLE_PUBL]	= { .type = NLA_NESTED }
+};
+
+/**
+ * struct name_info - name sequence publication info
+ * @node_list: circular list of publications made by own node
+ * @cluster_list: circular list of publications made by own cluster
+ * @zone_list: circular list of publications made by own zone
+ * @node_list_size: number of entries in "node_list"
+ * @cluster_list_size: number of entries in "cluster_list"
+ * @zone_list_size: number of entries in "zone_list"
+ *
+ * Note: The zone list always contains at least one entry, since all
+ *       publications of the associated name sequence belong to it.
+ *       (The cluster and node lists may be empty.)
+ */
+struct name_info {
+	struct list_head node_list;
+	struct list_head cluster_list;
+	struct list_head zone_list;
+	u32 node_list_size;
+	u32 cluster_list_size;
+	u32 zone_list_size;
+};
+
+/**
+ * struct sub_seq - container for all published instances of a name sequence
+ * @lower: name sequence lower bound
+ * @upper: name sequence upper bound
+ * @info: pointer to name sequence publication info
+ */
+struct sub_seq {
+	u32 lower;
+	u32 upper;
+	struct name_info *info;
+};
+
+/**
+ * struct name_seq - container for all published instances of a name type
+ * @type: 32 bit 'type' value for name sequence
+ * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type';
+ *        sub-sequences are sorted in ascending order
+ * @alloc: number of sub-sequences currently in array
+ * @first_free: array index of first unused sub-sequence entry
+ * @ns_list: links to adjacent name sequences in hash chain
+ * @subscriptions: list of subscriptions for this 'type'
+ * @lock: spinlock controlling access to publication lists of all sub-sequences
+ * @rcu: RCU callback head used for deferred freeing
+ */
+struct name_seq {
+	u32 type;
+	struct sub_seq *sseqs;
+	u32 alloc;
+	u32 first_free;
+	struct hlist_node ns_list;
+	struct list_head subscriptions;
+	spinlock_t lock;
+	struct rcu_head rcu;
+};
+
+static int hash(int x)
+{
+	return x & (TIPC_NAMETBL_SIZE - 1);
+}
+
+/**
+ * publ_create - create a publication structure
+ */
+static struct publication *publ_create(u32 type, u32 lower, u32 upper,
+				       u32 scope, u32 node, u32 port_ref,
+				       u32 key)
+{
+	struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
+	if (publ == NULL) {
+		pr_warn("Publication creation failure, no memory\n");
+		return NULL;
+	}
+
+	publ->type = type;
+	publ->lower = lower;
+	publ->upper = upper;
+	publ->scope = scope;
+	publ->node = node;
+	publ->ref = port_ref;
+	publ->key = key;
+	INIT_LIST_HEAD(&publ->pport_list);
+	return publ;
+}
+
+/**
+ * tipc_subseq_alloc - allocate a specified number of sub-sequence structures
+ */
+static struct sub_seq *tipc_subseq_alloc(u32 cnt)
+{
+	return kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC);
+}
+
+/**
+ * tipc_nameseq_create - create a name sequence structure for the specified 'type'
+ *
+ * Allocates a single sub-sequence structure and sets it to all 0's.
+ */
+static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head)
+{
+	struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC);
+	struct sub_seq *sseq = tipc_subseq_alloc(1);
+
+	if (!nseq || !sseq) {
+		pr_warn("Name sequence creation failed, no memory\n");
+		kfree(nseq);
+		kfree(sseq);
+		return NULL;
+	}
+
+	spin_lock_init(&nseq->lock);
+	nseq->type = type;
+	nseq->sseqs = sseq;
+	nseq->alloc = 1;
+	INIT_HLIST_NODE(&nseq->ns_list);
+	INIT_LIST_HEAD(&nseq->subscriptions);
+	hlist_add_head_rcu(&nseq->ns_list, seq_head);
+	return nseq;
+}
+
+/**
+ * nameseq_find_subseq - find sub-sequence (if any) matching a name instance
+ *
+ * Very time-critical, so binary searches through sub-sequence array.
+ */
+static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq,
+					   u32 instance)
+{
+	struct sub_seq *sseqs = nseq->sseqs;
+	int low = 0;
+	int high = nseq->first_free - 1;
+	int mid;
+
+	while (low <= high) {
+		mid = (low + high) / 2;
+		if (instance < sseqs[mid].lower)
+			high = mid - 1;
+		else if (instance > sseqs[mid].upper)
+			low = mid + 1;
+		else
+			return &sseqs[mid];
+	}
+	return NULL;
+}
+
+/**
+ * nameseq_locate_subseq - determine position of name instance in sub-sequence
+ *
+ * Returns index in sub-sequence array of the entry that contains the specified
+ * instance value; if no entry contains that value, returns the position
+ * where a new entry for it would be inserted in the array.
+ *
+ * Note: Similar to binary search code for locating a sub-sequence.
+ */
+static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance)
+{
+	struct sub_seq *sseqs = nseq->sseqs;
+	int low = 0;
+	int high = nseq->first_free - 1;
+	int mid;
+
+	while (low <= high) {
+		mid = (low + high) / 2;
+		if (instance < sseqs[mid].lower)
+			high = mid - 1;
+		else if (instance > sseqs[mid].upper)
+			low = mid + 1;
+		else
+			return mid;
+	}
+	return low;
+}
+
+/**
+ * tipc_nameseq_insert_publ
+ */
+static struct publication *tipc_nameseq_insert_publ(struct net *net,
+						    struct name_seq *nseq,
+						    u32 type, u32 lower,
+						    u32 upper, u32 scope,
+						    u32 node, u32 port, u32 key)
+{
+	struct tipc_subscription *s;
+	struct tipc_subscription *st;
+	struct publication *publ;
+	struct sub_seq *sseq;
+	struct name_info *info;
+	int created_subseq = 0;
+
+	sseq = nameseq_find_subseq(nseq, lower);
+	if (sseq) {
+
+		/* Lower end overlaps existing entry => need an exact match */
+		if ((sseq->lower != lower) || (sseq->upper != upper)) {
+			return NULL;
+		}
+
+		info = sseq->info;
+
+		/* Check if an identical publication already exists */
+		list_for_each_entry(publ, &info->zone_list, zone_list) {
+			if ((publ->ref == port) && (publ->key == key) &&
+			    (!publ->node || (publ->node == node)))
+				return NULL;
+		}
+	} else {
+		u32 inspos;
+		struct sub_seq *freesseq;
+
+		/* Find where lower end should be inserted */
+		inspos = nameseq_locate_subseq(nseq, lower);
+
+		/* Fail if upper end overlaps into an existing entry */
+		if ((inspos < nseq->first_free) &&
+		    (upper >= nseq->sseqs[inspos].lower)) {
+			return NULL;
+		}
+
+		/* Ensure there is space for new sub-sequence */
+		if (nseq->first_free == nseq->alloc) {
+			struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2);
+
+			if (!sseqs) {
+				pr_warn("Cannot publish {%u,%u,%u}, no memory\n",
+					type, lower, upper);
+				return NULL;
+			}
+			memcpy(sseqs, nseq->sseqs,
+			       nseq->alloc * sizeof(struct sub_seq));
+			kfree(nseq->sseqs);
+			nseq->sseqs = sseqs;
+			nseq->alloc *= 2;
+		}
+
+		info = kzalloc(sizeof(*info), GFP_ATOMIC);
+		if (!info) {
+			pr_warn("Cannot publish {%u,%u,%u}, no memory\n",
+				type, lower, upper);
+			return NULL;
+		}
+
+		INIT_LIST_HEAD(&info->node_list);
+		INIT_LIST_HEAD(&info->cluster_list);
+		INIT_LIST_HEAD(&info->zone_list);
+
+		/* Insert new sub-sequence */
+		sseq = &nseq->sseqs[inspos];
+		freesseq = &nseq->sseqs[nseq->first_free];
+		memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof(*sseq));
+		memset(sseq, 0, sizeof(*sseq));
+		nseq->first_free++;
+		sseq->lower = lower;
+		sseq->upper = upper;
+		sseq->info = info;
+		created_subseq = 1;
+	}
+
+	/* Insert a publication */
+	publ = publ_create(type, lower, upper, scope, node, port, key);
+	if (!publ)
+		return NULL;
+
+	list_add(&publ->zone_list, &info->zone_list);
+	info->zone_list_size++;
+
+	if (in_own_cluster(net, node)) {
+		list_add(&publ->cluster_list, &info->cluster_list);
+		info->cluster_list_size++;
+	}
+
+	if (in_own_node(net, node)) {
+		list_add(&publ->node_list, &info->node_list);
+		info->node_list_size++;
+	}
+
+	/* Any subscriptions waiting for notification?  */
+	list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
+		tipc_subscr_report_overlap(s,
+					   publ->lower,
+					   publ->upper,
+					   TIPC_PUBLISHED,
+					   publ->ref,
+					   publ->node,
+					   created_subseq);
+	}
+	return publ;
+}
+
+/**
+ * tipc_nameseq_remove_publ
+ *
+ * NOTE: There may be cases where TIPC is asked to remove a publication
+ * that is not in the name table.  For example, if another node issues a
+ * publication for a name sequence that overlaps an existing name sequence
+ * the publication will not be recorded, which means the publication won't
+ * be found when the name sequence is later withdrawn by that node.
+ * A failed withdraw request simply returns a failure indication and lets the
+ * caller issue any error or warning messages associated with such a problem.
+ */
+static struct publication *tipc_nameseq_remove_publ(struct net *net,
+						    struct name_seq *nseq,
+						    u32 inst, u32 node,
+						    u32 ref, u32 key)
+{
+	struct publication *publ;
+	struct sub_seq *sseq = nameseq_find_subseq(nseq, inst);
+	struct name_info *info;
+	struct sub_seq *free;
+	struct tipc_subscription *s, *st;
+	int removed_subseq = 0;
+
+	if (!sseq)
+		return NULL;
+
+	info = sseq->info;
+
+	/* Locate publication, if it exists */
+	list_for_each_entry(publ, &info->zone_list, zone_list) {
+		if ((publ->key == key) && (publ->ref == ref) &&
+		    (!publ->node || (publ->node == node)))
+			goto found;
+	}
+	return NULL;
+
+found:
+	/* Remove publication from zone scope list */
+	list_del(&publ->zone_list);
+	info->zone_list_size--;
+
+	/* Remove publication from cluster scope list, if present */
+	if (in_own_cluster(net, node)) {
+		list_del(&publ->cluster_list);
+		info->cluster_list_size--;
+	}
+
+	/* Remove publication from node scope list, if present */
+	if (in_own_node(net, node)) {
+		list_del(&publ->node_list);
+		info->node_list_size--;
+	}
+
+	/* Contract subseq list if no more publications for that subseq */
+	if (list_empty(&info->zone_list)) {
+		kfree(info);
+		free = &nseq->sseqs[nseq->first_free--];
+		memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof(*sseq));
+		removed_subseq = 1;
+	}
+
+	/* Notify any waiting subscriptions */
+	list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
+		tipc_subscr_report_overlap(s,
+					   publ->lower,
+					   publ->upper,
+					   TIPC_WITHDRAWN,
+					   publ->ref,
+					   publ->node,
+					   removed_subseq);
+	}
+
+	return publ;
+}
+
+/**
+ * tipc_nameseq_subscribe - attach a subscription, and issue
+ * the prescribed number of events if there is any sub-
+ * sequence overlapping with the requested sequence
+ */
+static void tipc_nameseq_subscribe(struct name_seq *nseq,
+				   struct tipc_subscription *s)
+{
+	struct sub_seq *sseq = nseq->sseqs;
+
+	list_add(&s->nameseq_list, &nseq->subscriptions);
+
+	if (!sseq)
+		return;
+
+	while (sseq != &nseq->sseqs[nseq->first_free]) {
+		if (tipc_subscr_overlap(s, sseq->lower, sseq->upper)) {
+			struct publication *crs;
+			struct name_info *info = sseq->info;
+			int must_report = 1;
+
+			list_for_each_entry(crs, &info->zone_list, zone_list) {
+				tipc_subscr_report_overlap(s,
+							   sseq->lower,
+							   sseq->upper,
+							   TIPC_PUBLISHED,
+							   crs->ref,
+							   crs->node,
+							   must_report);
+				must_report = 0;
+			}
+		}
+		sseq++;
+	}
+}
+
+static struct name_seq *nametbl_find_seq(struct net *net, u32 type)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct hlist_head *seq_head;
+	struct name_seq *ns;
+
+	seq_head = &tn->nametbl->seq_hlist[hash(type)];
+	hlist_for_each_entry_rcu(ns, seq_head, ns_list) {
+		if (ns->type == type)
+			return ns;
+	}
+
+	return NULL;
+};
+
+struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type,
+					     u32 lower, u32 upper, u32 scope,
+					     u32 node, u32 port, u32 key)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct publication *publ;
+	struct name_seq *seq = nametbl_find_seq(net, type);
+	int index = hash(type);
+
+	if ((scope < TIPC_ZONE_SCOPE) || (scope > TIPC_NODE_SCOPE) ||
+	    (lower > upper)) {
+		pr_debug("Failed to publish illegal {%u,%u,%u} with scope %u\n",
+			 type, lower, upper, scope);
+		return NULL;
+	}
+
+	if (!seq)
+		seq = tipc_nameseq_create(type, &tn->nametbl->seq_hlist[index]);
+	if (!seq)
+		return NULL;
+
+	spin_lock_bh(&seq->lock);
+	publ = tipc_nameseq_insert_publ(net, seq, type, lower, upper,
+					scope, node, port, key);
+	spin_unlock_bh(&seq->lock);
+	return publ;
+}
+
+struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
+					     u32 lower, u32 node, u32 ref,
+					     u32 key)
+{
+	struct publication *publ;
+	struct name_seq *seq = nametbl_find_seq(net, type);
+
+	if (!seq)
+		return NULL;
+
+	spin_lock_bh(&seq->lock);
+	publ = tipc_nameseq_remove_publ(net, seq, lower, node, ref, key);
+	if (!seq->first_free && list_empty(&seq->subscriptions)) {
+		hlist_del_init_rcu(&seq->ns_list);
+		kfree(seq->sseqs);
+		spin_unlock_bh(&seq->lock);
+		kfree_rcu(seq, rcu);
+		return publ;
+	}
+	spin_unlock_bh(&seq->lock);
+	return publ;
+}
+
+/**
+ * tipc_nametbl_translate - perform name translation
+ *
+ * On entry, 'destnode' is the search domain used during translation.
+ *
+ * On exit:
+ * - if name translation is deferred to another node/cluster/zone,
+ *   leaves 'destnode' unchanged (will be non-zero) and returns 0
+ * - if name translation is attempted and succeeds, sets 'destnode'
+ *   to publishing node and returns port reference (will be non-zero)
+ * - if name translation is attempted and fails, sets 'destnode' to 0
+ *   and returns 0
+ */
+u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance,
+			   u32 *destnode)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct sub_seq *sseq;
+	struct name_info *info;
+	struct publication *publ;
+	struct name_seq *seq;
+	u32 ref = 0;
+	u32 node = 0;
+
+	if (!tipc_in_scope(*destnode, tn->own_addr))
+		return 0;
+
+	rcu_read_lock();
+	seq = nametbl_find_seq(net, type);
+	if (unlikely(!seq))
+		goto not_found;
+	spin_lock_bh(&seq->lock);
+	sseq = nameseq_find_subseq(seq, instance);
+	if (unlikely(!sseq))
+		goto no_match;
+	info = sseq->info;
+
+	/* Closest-First Algorithm */
+	if (likely(!*destnode)) {
+		if (!list_empty(&info->node_list)) {
+			publ = list_first_entry(&info->node_list,
+						struct publication,
+						node_list);
+			list_move_tail(&publ->node_list,
+				       &info->node_list);
+		} else if (!list_empty(&info->cluster_list)) {
+			publ = list_first_entry(&info->cluster_list,
+						struct publication,
+						cluster_list);
+			list_move_tail(&publ->cluster_list,
+				       &info->cluster_list);
+		} else {
+			publ = list_first_entry(&info->zone_list,
+						struct publication,
+						zone_list);
+			list_move_tail(&publ->zone_list,
+				       &info->zone_list);
+		}
+	}
+
+	/* Round-Robin Algorithm */
+	else if (*destnode == tn->own_addr) {
+		if (list_empty(&info->node_list))
+			goto no_match;
+		publ = list_first_entry(&info->node_list, struct publication,
+					node_list);
+		list_move_tail(&publ->node_list, &info->node_list);
+	} else if (in_own_cluster_exact(net, *destnode)) {
+		if (list_empty(&info->cluster_list))
+			goto no_match;
+		publ = list_first_entry(&info->cluster_list, struct publication,
+					cluster_list);
+		list_move_tail(&publ->cluster_list, &info->cluster_list);
+	} else {
+		publ = list_first_entry(&info->zone_list, struct publication,
+					zone_list);
+		list_move_tail(&publ->zone_list, &info->zone_list);
+	}
+
+	ref = publ->ref;
+	node = publ->node;
+no_match:
+	spin_unlock_bh(&seq->lock);
+not_found:
+	rcu_read_unlock();
+	*destnode = node;
+	return ref;
+}
+
+/**
+ * tipc_nametbl_mc_translate - find multicast destinations
+ *
+ * Creates list of all local ports that overlap the given multicast address;
+ * also determines if any off-node ports overlap.
+ *
+ * Note: Publications with a scope narrower than 'limit' are ignored.
+ * (i.e. local node-scope publications mustn't receive messages arriving
+ * from another node, even if the multcast link brought it here)
+ *
+ * Returns non-zero if any off-node ports overlap
+ */
+int tipc_nametbl_mc_translate(struct net *net, u32 type, u32 lower, u32 upper,
+			      u32 limit, struct tipc_plist *dports)
+{
+	struct name_seq *seq;
+	struct sub_seq *sseq;
+	struct sub_seq *sseq_stop;
+	struct name_info *info;
+	int res = 0;
+
+	rcu_read_lock();
+	seq = nametbl_find_seq(net, type);
+	if (!seq)
+		goto exit;
+
+	spin_lock_bh(&seq->lock);
+	sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
+	sseq_stop = seq->sseqs + seq->first_free;
+	for (; sseq != sseq_stop; sseq++) {
+		struct publication *publ;
+
+		if (sseq->lower > upper)
+			break;
+
+		info = sseq->info;
+		list_for_each_entry(publ, &info->node_list, node_list) {
+			if (publ->scope <= limit)
+				tipc_plist_push(dports, publ->ref);
+		}
+
+		if (info->cluster_list_size != info->node_list_size)
+			res = 1;
+	}
+	spin_unlock_bh(&seq->lock);
+exit:
+	rcu_read_unlock();
+	return res;
+}
+
+/*
+ * tipc_nametbl_publish - add name publication to network name tables
+ */
+struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
+					 u32 upper, u32 scope, u32 port_ref,
+					 u32 key)
+{
+	struct publication *publ;
+	struct sk_buff *buf = NULL;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	spin_lock_bh(&tn->nametbl_lock);
+	if (tn->nametbl->local_publ_count >= TIPC_MAX_PUBLICATIONS) {
+		pr_warn("Publication failed, local publication limit reached (%u)\n",
+			TIPC_MAX_PUBLICATIONS);
+		spin_unlock_bh(&tn->nametbl_lock);
+		return NULL;
+	}
+
+	publ = tipc_nametbl_insert_publ(net, type, lower, upper, scope,
+					tn->own_addr, port_ref, key);
+	if (likely(publ)) {
+		tn->nametbl->local_publ_count++;
+		buf = tipc_named_publish(net, publ);
+		/* Any pending external events? */
+		tipc_named_process_backlog(net);
+	}
+	spin_unlock_bh(&tn->nametbl_lock);
+
+	if (buf)
+		named_cluster_distribute(net, buf);
+	return publ;
+}
+
+/**
+ * tipc_nametbl_withdraw - withdraw name publication from network name tables
+ */
+int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower, u32 ref,
+			  u32 key)
+{
+	struct publication *publ;
+	struct sk_buff *skb = NULL;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	spin_lock_bh(&tn->nametbl_lock);
+	publ = tipc_nametbl_remove_publ(net, type, lower, tn->own_addr,
+					ref, key);
+	if (likely(publ)) {
+		tn->nametbl->local_publ_count--;
+		skb = tipc_named_withdraw(net, publ);
+		/* Any pending external events? */
+		tipc_named_process_backlog(net);
+		list_del_init(&publ->pport_list);
+		kfree_rcu(publ, rcu);
+	} else {
+		pr_err("Unable to remove local publication\n"
+		       "(type=%u, lower=%u, ref=%u, key=%u)\n",
+		       type, lower, ref, key);
+	}
+	spin_unlock_bh(&tn->nametbl_lock);
+
+	if (skb) {
+		named_cluster_distribute(net, skb);
+		return 1;
+	}
+	return 0;
+}
+
+/**
+ * tipc_nametbl_subscribe - add a subscription object to the name table
+ */
+void tipc_nametbl_subscribe(struct tipc_subscription *s)
+{
+	struct tipc_net *tn = net_generic(s->net, tipc_net_id);
+	u32 type = s->seq.type;
+	int index = hash(type);
+	struct name_seq *seq;
+
+	spin_lock_bh(&tn->nametbl_lock);
+	seq = nametbl_find_seq(s->net, type);
+	if (!seq)
+		seq = tipc_nameseq_create(type, &tn->nametbl->seq_hlist[index]);
+	if (seq) {
+		spin_lock_bh(&seq->lock);
+		tipc_nameseq_subscribe(seq, s);
+		spin_unlock_bh(&seq->lock);
+	} else {
+		pr_warn("Failed to create subscription for {%u,%u,%u}\n",
+			s->seq.type, s->seq.lower, s->seq.upper);
+	}
+	spin_unlock_bh(&tn->nametbl_lock);
+}
+
+/**
+ * tipc_nametbl_unsubscribe - remove a subscription object from name table
+ */
+void tipc_nametbl_unsubscribe(struct tipc_subscription *s)
+{
+	struct tipc_net *tn = net_generic(s->net, tipc_net_id);
+	struct name_seq *seq;
+
+	spin_lock_bh(&tn->nametbl_lock);
+	seq = nametbl_find_seq(s->net, s->seq.type);
+	if (seq != NULL) {
+		spin_lock_bh(&seq->lock);
+		list_del_init(&s->nameseq_list);
+		if (!seq->first_free && list_empty(&seq->subscriptions)) {
+			hlist_del_init_rcu(&seq->ns_list);
+			kfree(seq->sseqs);
+			spin_unlock_bh(&seq->lock);
+			kfree_rcu(seq, rcu);
+		} else {
+			spin_unlock_bh(&seq->lock);
+		}
+	}
+	spin_unlock_bh(&tn->nametbl_lock);
+}
+
+int tipc_nametbl_init(struct net *net)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct name_table *tipc_nametbl;
+	int i;
+
+	tipc_nametbl = kzalloc(sizeof(*tipc_nametbl), GFP_ATOMIC);
+	if (!tipc_nametbl)
+		return -ENOMEM;
+
+	for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
+		INIT_HLIST_HEAD(&tipc_nametbl->seq_hlist[i]);
+
+	INIT_LIST_HEAD(&tipc_nametbl->publ_list[TIPC_ZONE_SCOPE]);
+	INIT_LIST_HEAD(&tipc_nametbl->publ_list[TIPC_CLUSTER_SCOPE]);
+	INIT_LIST_HEAD(&tipc_nametbl->publ_list[TIPC_NODE_SCOPE]);
+	tn->nametbl = tipc_nametbl;
+	spin_lock_init(&tn->nametbl_lock);
+	return 0;
+}
+
+/**
+ * tipc_purge_publications - remove all publications for a given type
+ *
+ * tipc_nametbl_lock must be held when calling this function
+ */
+static void tipc_purge_publications(struct net *net, struct name_seq *seq)
+{
+	struct publication *publ, *safe;
+	struct sub_seq *sseq;
+	struct name_info *info;
+
+	spin_lock_bh(&seq->lock);
+	sseq = seq->sseqs;
+	info = sseq->info;
+	list_for_each_entry_safe(publ, safe, &info->zone_list, zone_list) {
+		tipc_nameseq_remove_publ(net, seq, publ->lower, publ->node,
+					 publ->ref, publ->key);
+		kfree_rcu(publ, rcu);
+	}
+	hlist_del_init_rcu(&seq->ns_list);
+	kfree(seq->sseqs);
+	spin_unlock_bh(&seq->lock);
+
+	kfree_rcu(seq, rcu);
+}
+
+void tipc_nametbl_stop(struct net *net)
+{
+	u32 i;
+	struct name_seq *seq;
+	struct hlist_head *seq_head;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct name_table *tipc_nametbl = tn->nametbl;
+
+	/* Verify name table is empty and purge any lingering
+	 * publications, then release the name table
+	 */
+	spin_lock_bh(&tn->nametbl_lock);
+	for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
+		if (hlist_empty(&tipc_nametbl->seq_hlist[i]))
+			continue;
+		seq_head = &tipc_nametbl->seq_hlist[i];
+		hlist_for_each_entry_rcu(seq, seq_head, ns_list) {
+			tipc_purge_publications(net, seq);
+		}
+	}
+	spin_unlock_bh(&tn->nametbl_lock);
+
+	synchronize_net();
+	kfree(tipc_nametbl);
+
+}
+
+static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
+					struct name_seq *seq,
+					struct sub_seq *sseq, u32 *last_publ)
+{
+	void *hdr;
+	struct nlattr *attrs;
+	struct nlattr *publ;
+	struct publication *p;
+
+	if (*last_publ) {
+		list_for_each_entry(p, &sseq->info->zone_list, zone_list)
+			if (p->key == *last_publ)
+				break;
+		if (p->key != *last_publ)
+			return -EPIPE;
+	} else {
+		p = list_first_entry(&sseq->info->zone_list, struct publication,
+				     zone_list);
+	}
+
+	list_for_each_entry_from(p, &sseq->info->zone_list, zone_list) {
+		*last_publ = p->key;
+
+		hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
+				  &tipc_genl_family, NLM_F_MULTI,
+				  TIPC_NL_NAME_TABLE_GET);
+		if (!hdr)
+			return -EMSGSIZE;
+
+		attrs = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE);
+		if (!attrs)
+			goto msg_full;
+
+		publ = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
+		if (!publ)
+			goto attr_msg_full;
+
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, seq->type))
+			goto publ_msg_full;
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sseq->lower))
+			goto publ_msg_full;
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sseq->upper))
+			goto publ_msg_full;
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
+			goto publ_msg_full;
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
+			goto publ_msg_full;
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->ref))
+			goto publ_msg_full;
+		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
+			goto publ_msg_full;
+
+		nla_nest_end(msg->skb, publ);
+		nla_nest_end(msg->skb, attrs);
+		genlmsg_end(msg->skb, hdr);
+	}
+	*last_publ = 0;
+
+	return 0;
+
+publ_msg_full:
+	nla_nest_cancel(msg->skb, publ);
+attr_msg_full:
+	nla_nest_cancel(msg->skb, attrs);
+msg_full:
+	genlmsg_cancel(msg->skb, hdr);
+
+	return -EMSGSIZE;
+}
+
+static int __tipc_nl_subseq_list(struct tipc_nl_msg *msg, struct name_seq *seq,
+				 u32 *last_lower, u32 *last_publ)
+{
+	struct sub_seq *sseq;
+	struct sub_seq *sseq_start;
+	int err;
+
+	if (*last_lower) {
+		sseq_start = nameseq_find_subseq(seq, *last_lower);
+		if (!sseq_start)
+			return -EPIPE;
+	} else {
+		sseq_start = seq->sseqs;
+	}
+
+	for (sseq = sseq_start; sseq != &seq->sseqs[seq->first_free]; sseq++) {
+		err = __tipc_nl_add_nametable_publ(msg, seq, sseq, last_publ);
+		if (err) {
+			*last_lower = sseq->lower;
+			return err;
+		}
+	}
+	*last_lower = 0;
+
+	return 0;
+}
+
+static int tipc_nl_seq_list(struct net *net, struct tipc_nl_msg *msg,
+			    u32 *last_type, u32 *last_lower, u32 *last_publ)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct hlist_head *seq_head;
+	struct name_seq *seq = NULL;
+	int err;
+	int i;
+
+	if (*last_type)
+		i = hash(*last_type);
+	else
+		i = 0;
+
+	for (; i < TIPC_NAMETBL_SIZE; i++) {
+		seq_head = &tn->nametbl->seq_hlist[i];
+
+		if (*last_type) {
+			seq = nametbl_find_seq(net, *last_type);
+			if (!seq)
+				return -EPIPE;
+		} else {
+			hlist_for_each_entry_rcu(seq, seq_head, ns_list)
+				break;
+			if (!seq)
+				continue;
+		}
+
+		hlist_for_each_entry_from_rcu(seq, ns_list) {
+			spin_lock_bh(&seq->lock);
+			err = __tipc_nl_subseq_list(msg, seq, last_lower,
+						    last_publ);
+
+			if (err) {
+				*last_type = seq->type;
+				spin_unlock_bh(&seq->lock);
+				return err;
+			}
+			spin_unlock_bh(&seq->lock);
+		}
+		*last_type = 0;
+	}
+	return 0;
+}
+
+int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	int err;
+	int done = cb->args[3];
+	u32 last_type = cb->args[0];
+	u32 last_lower = cb->args[1];
+	u32 last_publ = cb->args[2];
+	struct net *net = sock_net(skb->sk);
+	struct tipc_nl_msg msg;
+
+	if (done)
+		return 0;
+
+	msg.skb = skb;
+	msg.portid = NETLINK_CB(cb->skb).portid;
+	msg.seq = cb->nlh->nlmsg_seq;
+
+	rcu_read_lock();
+	err = tipc_nl_seq_list(net, &msg, &last_type, &last_lower, &last_publ);
+	if (!err) {
+		done = 1;
+	} else if (err != -EMSGSIZE) {
+		/* We never set seq or call nl_dump_check_consistent() this
+		 * means that setting prev_seq here will cause the consistence
+		 * check to fail in the netlink callback handler. Resulting in
+		 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
+		 * we got an error.
+		 */
+		cb->prev_seq = 1;
+	}
+	rcu_read_unlock();
+
+	cb->args[0] = last_type;
+	cb->args[1] = last_lower;
+	cb->args[2] = last_publ;
+	cb->args[3] = done;
+
+	return skb->len;
+}
+
+void tipc_plist_push(struct tipc_plist *pl, u32 port)
+{
+	struct tipc_plist *nl;
+
+	if (likely(!pl->port)) {
+		pl->port = port;
+		return;
+	}
+	if (pl->port == port)
+		return;
+	list_for_each_entry(nl, &pl->list, list) {
+		if (nl->port == port)
+			return;
+	}
+	nl = kmalloc(sizeof(*nl), GFP_ATOMIC);
+	if (nl) {
+		nl->port = port;
+		list_add(&nl->list, &pl->list);
+	}
+}
+
+u32 tipc_plist_pop(struct tipc_plist *pl)
+{
+	struct tipc_plist *nl;
+	u32 port = 0;
+
+	if (likely(list_empty(&pl->list))) {
+		port = pl->port;
+		pl->port = 0;
+		return port;
+	}
+	nl = list_first_entry(&pl->list, typeof(*nl), list);
+	port = nl->port;
+	list_del(&nl->list);
+	kfree(nl);
+	return port;
+}