/*
* net/tipc/name_distr.c: TIPC name distribution code
*
* Copyright (c) 2000-2006, 2014, Ericsson AB
* Copyright (c) 2005, 2010-2011, 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 "link.h"
#include "name_distr.h"
/**
* struct publ_list - list of publications made by this node
* @list: circular list of publications
* @list_size: number of entries in list
*/
struct publ_list {
struct list_head list;
u32 size;
};
static struct publ_list publ_zone = {
.list = LIST_HEAD_INIT(publ_zone.list),
.size = 0,
};
static struct publ_list publ_cluster = {
.list = LIST_HEAD_INIT(publ_cluster.list),
.size = 0,
};
static struct publ_list publ_node = {
.list = LIST_HEAD_INIT(publ_node.list),
.size = 0,
};
static struct publ_list *publ_lists[] = {
NULL,
&publ_zone, /* publ_lists[TIPC_ZONE_SCOPE] */
&publ_cluster, /* publ_lists[TIPC_CLUSTER_SCOPE] */
&publ_node /* publ_lists[TIPC_NODE_SCOPE] */
};
int sysctl_tipc_named_timeout __read_mostly = 2000;
/**
* struct tipc_dist_queue - queue holding deferred name table updates
*/
static struct list_head tipc_dist_queue = LIST_HEAD_INIT(tipc_dist_queue);
struct distr_queue_item {
struct distr_item i;
u32 dtype;
u32 node;
unsigned long expires;
struct list_head next;
};
/**
* publ_to_item - add publication info to a publication message
*/
static void publ_to_item(struct distr_item *i, struct publication *p)
{
i->type = htonl(p->type);
i->lower = htonl(p->lower);
i->upper = htonl(p->upper);
i->ref = htonl(p->ref);
i->key = htonl(p->key);
}
/**
* named_prepare_buf - allocate & initialize a publication message
*/
static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
{
struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
struct tipc_msg *msg;
if (buf != NULL) {
msg = buf_msg(buf);
tipc_msg_init(msg, NAME_DISTRIBUTOR, type, INT_H_SIZE, dest);
msg_set_size(msg, INT_H_SIZE + size);
}
return buf;
}
void named_cluster_distribute(struct sk_buff *buf)
{
struct sk_buff *obuf;
struct tipc_node *node;
u32 dnode;
rcu_read_lock();
list_for_each_entry_rcu(node, &tipc_node_list, list) {
dnode = node->addr;
if (in_own_node(dnode))
continue;
if (!tipc_node_active_links(node))
continue;
obuf = skb_copy(buf, GFP_ATOMIC);
if (!obuf)
break;
msg_set_destnode(buf_msg(obuf), dnode);
tipc_link_xmit(obuf, dnode, dnode);
}
rcu_read_unlock();
kfree_skb(buf);
}
/**
* tipc_named_publish - tell other nodes about a new publication by this node
*/
struct sk_buff *tipc_named_publish(struct publication *publ)
{
struct sk_buff *buf;
struct distr_item *item;
list_add_tail(&publ->local_list, &publ_lists[publ->scope]->list);
publ_lists[publ->scope]->size++;
if (publ->scope == TIPC_NODE_SCOPE)
return NULL;
buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
if (!buf) {
pr_warn("Publication distribution failure\n");
return NULL;
}
item = (struct distr_item *)msg_data(buf_msg(buf));
publ_to_item(item, publ);
return buf;
}
/**
* tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
*/
struct sk_buff *tipc_named_withdraw(struct publication *publ)
{
struct sk_buff *buf;
struct distr_item *item;
list_del(&publ->local_list);
publ_lists[publ->scope]->size--;
if (publ->scope == TIPC_NODE_SCOPE)
return NULL;
buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
if (!buf) {
pr_warn("Withdrawal distribution failure\n");
return NULL;
}
item = (struct distr_item *)msg_data(buf_msg(buf));
publ_to_item(item, publ);
return buf;
}
/**
* named_distribute - prepare name info for bulk distribution to another node
* @msg_list: list of messages (buffers) to be returned from this function
* @dnode: node to be updated
* @pls: linked list of publication items to be packed into buffer chain
*/
static void named_distribute(struct list_head *msg_list, u32 dnode,
struct publ_list *pls)
{
struct publication *publ;
struct sk_buff *buf = NULL;
struct distr_item *item = NULL;
uint dsz = pls->size * ITEM_SIZE;
uint msg_dsz = (tipc_node_get_mtu(dnode, 0) / ITEM_SIZE) * ITEM_SIZE;
uint rem = dsz;
uint msg_rem = 0;
list_for_each_entry(publ, &pls->list, local_list) {
/* Prepare next buffer: */
if (!buf) {
msg_rem = min_t(uint, rem, msg_dsz);
rem -= msg_rem;
buf = named_prepare_buf(PUBLICATION, msg_rem, dnode);
if (!buf) {
pr_warn("Bulk publication failure\n");
return;
}
item = (struct distr_item *)msg_data(buf_msg(buf));
}
/* Pack publication into message: */
publ_to_item(item, publ);
item++;
msg_rem -= ITEM_SIZE;
/* Append full buffer to list: */
if (!msg_rem) {
list_add_tail((struct list_head *)buf, msg_list);
buf = NULL;
}
}
}
/**
* tipc_named_node_up - tell specified node about all publications by this node
*/
void tipc_named_node_up(u32 dnode)
{
LIST_HEAD(msg_list);
struct sk_buff *buf_chain;
read_lock_bh(&tipc_nametbl_lock);
named_distribute(&msg_list, dnode, &publ_cluster);
named_distribute(&msg_list, dnode, &publ_zone);
read_unlock_bh(&tipc_nametbl_lock);
/* Convert circular list to linear list and send: */
buf_chain = (struct sk_buff *)msg_list.next;
((struct sk_buff *)msg_list.prev)->next = NULL;
tipc_link_xmit(buf_chain, dnode, dnode);
}
/**
* named_purge_publ - remove publication associated with a failed node
*
* Invoked for each publication issued by a newly failed node.
* Removes publication structure from name table & deletes it.
*/
static void named_purge_publ(struct publication *publ)
{
struct publication *p;
write_lock_bh(&tipc_nametbl_lock);
p = tipc_nametbl_remove_publ(publ->type, publ->lower,
publ->node, publ->ref, publ->key);
if (p)
tipc_nodesub_unsubscribe(&p->subscr);
write_unlock_bh(&tipc_nametbl_lock);
if (p != publ) {
pr_err("Unable to remove publication from failed node\n"
" (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
publ->type, publ->lower, publ->node, publ->ref,
publ->key);
}
kfree(p);
}
/**
* tipc_update_nametbl - try to process a nametable update and notify
* subscribers
*
* tipc_nametbl_lock must be held.
* Returns the publication item if successful, otherwise NULL.
*/
static bool tipc_update_nametbl(struct distr_item *i, u32 node, u32 dtype)
{
struct publication *publ = NULL;
if (dtype == PUBLICATION) {
publ = tipc_nametbl_insert_publ(ntohl(i->type), ntohl(i->lower),
ntohl(i->upper),
TIPC_CLUSTER_SCOPE, node,
ntohl(i->ref), ntohl(i->key));
if (publ) {
tipc_nodesub_subscribe(&publ->subscr, node, publ,
(net_ev_handler)
named_purge_publ);
return true;
}
} else if (dtype == WITHDRAWAL) {
publ = tipc_nametbl_remove_publ(ntohl(i->type), ntohl(i->lower),
node, ntohl(i->ref),
ntohl(i->key));
if (publ) {
tipc_nodesub_unsubscribe(&publ->subscr);
kfree(publ);
return true;
}
} else {
pr_warn("Unrecognized name table message received\n");
}
return false;
}
/**
* tipc_named_add_backlog - add a failed name table update to the backlog
*
*/
static void tipc_named_add_backlog(struct distr_item *i, u32 type, u32 node)
{
struct distr_queue_item *e;
unsigned long now = get_jiffies_64();
e = kzalloc(sizeof(*e), GFP_ATOMIC);
if (!e)
return;
e->dtype = type;
e->node = node;
e->expires = now + msecs_to_jiffies(sysctl_tipc_named_timeout);
memcpy(e, i, sizeof(*i));
list_add_tail(&e->next, &tipc_dist_queue);
}
/**
* tipc_named_process_backlog - try to process any pending name table updates
* from the network.
*/
void tipc_named_process_backlog(void)
{
struct distr_queue_item *e, *tmp;
char addr[16];
unsigned long now = get_jiffies_64();
list_for_each_entry_safe(e, tmp, &tipc_dist_queue, next) {
if (time_after(e->expires, now)) {
if (!tipc_update_nametbl(&e->i, e->node, e->dtype))
continue;
} else {
tipc_addr_string_fill(addr, e->node);
pr_warn_ratelimited("Dropping name table update (%d) of {%u, %u, %u} from %s key=%u\n",
e->dtype, ntohl(e->i.type),
ntohl(e->i.lower),
ntohl(e->i.upper),
addr, ntohl(e->i.key));
}
list_del(&e->next);
kfree(e);
}
}
/**
* tipc_named_rcv - process name table update message sent by another node
*/
void tipc_named_rcv(struct sk_buff *buf)
{
struct tipc_msg *msg = buf_msg(buf);
struct distr_item *item = (struct distr_item *)msg_data(msg);
u32 count = msg_data_sz(msg) / ITEM_SIZE;
u32 node = msg_orignode(msg);
write_lock_bh(&tipc_nametbl_lock);
while (count--) {
if (!tipc_update_nametbl(item, node, msg_type(msg)))
tipc_named_add_backlog(item, msg_type(msg), node);
item++;
}
tipc_named_process_backlog();
write_unlock_bh(&tipc_nametbl_lock);
kfree_skb(buf);
}
/**
* tipc_named_reinit - re-initialize local publications
*
* This routine is called whenever TIPC networking is enabled.
* All name table entries published by this node are updated to reflect
* the node's new network address.
*/
void tipc_named_reinit(void)
{
struct publication *publ;
int scope;
write_lock_bh(&tipc_nametbl_lock);
for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
list_for_each_entry(publ, &publ_lists[scope]->list, local_list)
publ->node = tipc_own_addr;
write_unlock_bh(&tipc_nametbl_lock);
}
