/*
* net/tipc/node.c: TIPC node management routines
*
* Copyright (c) 2000-2006, Ericsson AB
* Copyright (c) 2005, 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 "cluster.h"
#include "net.h"
#include "addr.h"
#include "node_subscr.h"
#include "link.h"
#include "port.h"
#include "bearer.h"
#include "name_distr.h"
#include "net.h"
void node_print(struct print_buf *buf, struct node *n_ptr, char *str);
static void node_lost_contact(struct node *n_ptr);
static void node_established_contact(struct node *n_ptr);
struct node *nodes = NULL; /* sorted list of nodes within cluster */
u32 tipc_own_tag = 0;
struct node *node_create(u32 addr)
{
struct cluster *c_ptr;
struct node *n_ptr;
struct node **curr_node;
n_ptr = kmalloc(sizeof(*n_ptr),GFP_ATOMIC);
if (n_ptr != NULL) {
memset(n_ptr, 0, sizeof(*n_ptr));
n_ptr->addr = addr;
n_ptr->lock = SPIN_LOCK_UNLOCKED;
INIT_LIST_HEAD(&n_ptr->nsub);
c_ptr = cluster_find(addr);
if (c_ptr == NULL)
c_ptr = cluster_create(addr);
if (c_ptr != NULL) {
n_ptr->owner = c_ptr;
cluster_attach_node(c_ptr, n_ptr);
n_ptr->last_router = -1;
/* Insert node into ordered list */
for (curr_node = &nodes; *curr_node;
curr_node = &(*curr_node)->next) {
if (addr < (*curr_node)->addr) {
n_ptr->next = *curr_node;
break;
}
}
(*curr_node) = n_ptr;
} else {
kfree(n_ptr);
n_ptr = NULL;
}
}
return n_ptr;
}
void node_delete(struct node *n_ptr)
{
if (!n_ptr)
return;
#if 0
/* Not needed because links are already deleted via bearer_stop() */
u32 l_num;
for (l_num = 0; l_num < MAX_BEARERS; l_num++) {
link_delete(n_ptr->links[l_num]);
}
#endif
dbg("node %x deleted\n", n_ptr->addr);
kfree(n_ptr);
}
/**
* node_link_up - handle addition of link
*
* Link becomes active (alone or shared) or standby, depending on its priority.
*/
void node_link_up(struct node *n_ptr, struct link *l_ptr)
{
struct link **active = &n_ptr->active_links[0];
info("Established link <%s> on network plane %c\n",
l_ptr->name, l_ptr->b_ptr->net_plane);
if (!active[0]) {
dbg(" link %x into %x/%x\n", l_ptr, &active[0], &active[1]);
active[0] = active[1] = l_ptr;
node_established_contact(n_ptr);
return;
}
if (l_ptr->priority < active[0]->priority) {
info("Link is standby\n");
return;
}
link_send_duplicate(active[0], l_ptr);
if (l_ptr->priority == active[0]->priority) {
active[0] = l_ptr;
return;
}
info("Link <%s> on network plane %c becomes standby\n",
active[0]->name, active[0]->b_ptr->net_plane);
active[0] = active[1] = l_ptr;
}
/**
* node_select_active_links - select active link
*/
static void node_select_active_links(struct node *n_ptr)
{
struct link **active = &n_ptr->active_links[0];
u32 i;
u32 highest_prio = 0;
active[0] = active[1] = 0;
for (i = 0; i < MAX_BEARERS; i++) {
struct link *l_ptr = n_ptr->links[i];
if (!l_ptr || !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;
}
}
}
/**
* node_link_down - handle loss of link
*/
void node_link_down(struct node *n_ptr, struct link *l_ptr)
{
struct link **active;
if (!link_is_active(l_ptr)) {
info("Lost standby link <%s> on network plane %c\n",
l_ptr->name, l_ptr->b_ptr->net_plane);
return;
}
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 (node_is_up(n_ptr))
link_changeover(l_ptr);
else
node_lost_contact(n_ptr);
}
int node_has_active_links(struct node *n_ptr)
{
return (n_ptr &&
((n_ptr->active_links[0]) || (n_ptr->active_links[1])));
}
int node_has_redundant_links(struct node *n_ptr)
{
return (node_has_active_links(n_ptr) &&
(n_ptr->active_links[0] != n_ptr->active_links[1]));
}
int node_has_active_routes(struct node *n_ptr)
{
return (n_ptr && (n_ptr->last_router >= 0));
}
int node_is_up(struct node *n_ptr)
{
return (node_has_active_links(n_ptr) || node_has_active_routes(n_ptr));
}
struct node *node_attach_link(struct link *l_ptr)
{
struct node *n_ptr = node_find(l_ptr->addr);
if (!n_ptr)
n_ptr = node_create(l_ptr->addr);
if (n_ptr) {
u32 bearer_id = l_ptr->b_ptr->identity;
char addr_string[16];
assert(bearer_id < MAX_BEARERS);
if (n_ptr->link_cnt >= 2) {
char addr_string[16];
err("Attempt to create third link to %s\n",
addr_string_fill(addr_string, n_ptr->addr));
return 0;
}
if (!n_ptr->links[bearer_id]) {
n_ptr->links[bearer_id] = l_ptr;
net.zones[tipc_zone(l_ptr->addr)]->links++;
n_ptr->link_cnt++;
return n_ptr;
}
err("Attempt to establish second link on <%s> to <%s> \n",
l_ptr->b_ptr->publ.name,
addr_string_fill(addr_string, l_ptr->addr));
}
return 0;
}
void node_detach_link(struct node *n_ptr, struct link *l_ptr)
{
n_ptr->links[l_ptr->b_ptr->identity] = 0;
net.zones[tipc_zone(l_ptr->addr)]->links--;
n_ptr->link_cnt--;
}
/*
* Routing table management - five cases to handle:
*
* 1: A link towards a zone/cluster external node comes up.
* => Send a multicast message updating routing tables of all
* system nodes within own cluster that the new destination
* can be reached via this node.
* (node.establishedContact()=>cluster.multicastNewRoute())
*
* 2: A link towards a slave node comes up.
* => Send a multicast message updating routing tables of all
* system nodes within own cluster that the new destination
* can be reached via this node.
* (node.establishedContact()=>cluster.multicastNewRoute())
* => Send a message to the slave node about existence
* of all system nodes within cluster:
* (node.establishedContact()=>cluster.sendLocalRoutes())
*
* 3: A new cluster local system node becomes available.
* => Send message(s) to this particular node containing
* information about all cluster external and slave
* nodes which can be reached via this node.
* (node.establishedContact()==>network.sendExternalRoutes())
* (node.establishedContact()==>network.sendSlaveRoutes())
* => Send messages to all directly connected slave nodes
* containing information about the existence of the new node
* (node.establishedContact()=>cluster.multicastNewRoute())
*
* 4: The link towards a zone/cluster external node or slave
* node goes down.
* => Send a multcast message updating routing tables of all
* nodes within cluster that the new destination can not any
* longer be reached via this node.
* (node.lostAllLinks()=>cluster.bcastLostRoute())
*
* 5: A cluster local system node becomes unavailable.
* => Remove all references to this node from the local
* routing tables. Note: This is a completely node
* local operation.
* (node.lostAllLinks()=>network.removeAsRouter())
* => Send messages to all directly connected slave nodes
* containing information about loss of the node
* (node.establishedContact()=>cluster.multicastLostRoute())
*
*/
static void node_established_contact(struct node *n_ptr)
{
struct cluster *c_ptr;
dbg("node_established_contact:-> %x\n", n_ptr->addr);
if (!node_has_active_routes(n_ptr)) {
k_signal((Handler)named_node_up, n_ptr->addr);
}
/* Syncronize broadcast acks */
n_ptr->bclink.acked = bclink_get_last_sent();
if (is_slave(tipc_own_addr))
return;
if (!in_own_cluster(n_ptr->addr)) {
/* Usage case 1 (see above) */
c_ptr = cluster_find(tipc_own_addr);
if (!c_ptr)
c_ptr = cluster_create(tipc_own_addr);
if (c_ptr)
cluster_bcast_new_route(c_ptr, n_ptr->addr, 1,
tipc_max_nodes);
return;
}
c_ptr = n_ptr->owner;
if (is_slave(n_ptr->addr)) {
/* Usage case 2 (see above) */
cluster_bcast_new_route(c_ptr, n_ptr->addr, 1, tipc_max_nodes);
cluster_send_local_routes(c_ptr, n_ptr->addr);
return;
}
if (n_ptr->bclink.supported) {
nmap_add(&cluster_bcast_nodes, n_ptr->addr);
if (n_ptr->addr < tipc_own_addr)
tipc_own_tag++;
}
/* Case 3 (see above) */
net_send_external_routes(n_ptr->addr);
cluster_send_slave_routes(c_ptr, n_ptr->addr);
cluster_bcast_new_route(c_ptr, n_ptr->addr, LOWEST_SLAVE,
highest_allowed_slave);
}
static void node_lost_contact(struct node *n_ptr)
{
struct cluster *c_ptr;
struct node_subscr *ns, *tns;
char addr_string[16];
u32 i;
/* Clean up broadcast reception remains */
n_ptr->bclink.gap_after = n_ptr->bclink.gap_to = 0;
while (n_ptr->bclink.deferred_head) {
struct sk_buff* buf = n_ptr->bclink.deferred_head;
n_ptr->bclink.deferred_head = buf->next;
buf_discard(buf);
}
if (n_ptr->bclink.defragm) {
buf_discard(n_ptr->bclink.defragm);
n_ptr->bclink.defragm = NULL;
}
if (in_own_cluster(n_ptr->addr) && n_ptr->bclink.supported) {
bclink_acknowledge(n_ptr, mod(n_ptr->bclink.acked + 10000));
}
/* Update routing tables */
if (is_slave(tipc_own_addr)) {
net_remove_as_router(n_ptr->addr);
} else {
if (!in_own_cluster(n_ptr->addr)) {
/* Case 4 (see above) */
c_ptr = cluster_find(tipc_own_addr);
cluster_bcast_lost_route(c_ptr, n_ptr->addr, 1,
tipc_max_nodes);
} else {
/* Case 5 (see above) */
c_ptr = cluster_find(n_ptr->addr);
if (is_slave(n_ptr->addr)) {
cluster_bcast_lost_route(c_ptr, n_ptr->addr, 1,
tipc_max_nodes);
} else {
if (n_ptr->bclink.supported) {
nmap_remove(&cluster_bcast_nodes,
n_ptr->addr);
if (n_ptr->addr < tipc_own_addr)
tipc_own_tag--;
}
net_remove_as_router(n_ptr->addr);
cluster_bcast_lost_route(c_ptr, n_ptr->addr,
LOWEST_SLAVE,
highest_allowed_slave);
}
}
}
if (node_has_active_routes(n_ptr))
return;
info("Lost contact with %s\n",
addr_string_fill(addr_string, n_ptr->addr));
/* Abort link changeover */
for (i = 0; i < MAX_BEARERS; i++) {
struct 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;
link_reset_fragments(l_ptr);
}
/* Notify subscribers */
list_for_each_entry_safe(ns, tns, &n_ptr->nsub, nodesub_list) {
ns->node = 0;
list_del_init(&ns->nodesub_list);
k_signal((Handler)ns->handle_node_down,
(unsigned long)ns->usr_handle);
}
}
/**
* node_select_next_hop - find the next-hop node for a message
*
* Called by when cluster local lookup has failed.
*/
struct node *node_select_next_hop(u32 addr, u32 selector)
{
struct node *n_ptr;
u32 router_addr;
if (!addr_domain_valid(addr))
return 0;
/* Look for direct link to destination processsor */
n_ptr = node_find(addr);
if (n_ptr && node_has_active_links(n_ptr))
return n_ptr;
/* Cluster local system nodes *must* have direct links */
if (!is_slave(addr) && in_own_cluster(addr))
return 0;
/* Look for cluster local router with direct link to node */
router_addr = node_select_router(n_ptr, selector);
if (router_addr)
return node_select(router_addr, selector);
/* Slave nodes can only be accessed within own cluster via a
known router with direct link -- if no router was found,give up */
if (is_slave(addr))
return 0;
/* Inter zone/cluster -- find any direct link to remote cluster */
addr = tipc_addr(tipc_zone(addr), tipc_cluster(addr), 0);
n_ptr = net_select_remote_node(addr, selector);
if (n_ptr && node_has_active_links(n_ptr))
return n_ptr;
/* Last resort -- look for any router to anywhere in remote zone */
router_addr = net_select_router(addr, selector);
if (router_addr)
return node_select(router_addr, selector);
return 0;
}
/**
* node_select_router - select router to reach specified node
*
* Uses a deterministic and fair algorithm for selecting router node.
*/
u32 node_select_router(struct node *n_ptr, u32 ref)
{
u32 ulim;
u32 mask;
u32 start;
u32 r;
if (!n_ptr)
return 0;
if (n_ptr->last_router < 0)
return 0;
ulim = ((n_ptr->last_router + 1) * 32) - 1;
/* Start entry must be random */
mask = tipc_max_nodes;
while (mask > ulim)
mask >>= 1;
start = ref & mask;
r = start;
/* Lookup upwards with wrap-around */
do {
if (((n_ptr->routers[r / 32]) >> (r % 32)) & 1)
break;
} while (++r <= ulim);
if (r > ulim) {
r = 1;
do {
if (((n_ptr->routers[r / 32]) >> (r % 32)) & 1)
break;
} while (++r < start);
assert(r != start);
}
assert(r && (r <= ulim));
return tipc_addr(own_zone(), own_cluster(), r);
}
void node_add_router(struct node *n_ptr, u32 router)
{
u32 r_num = tipc_node(router);
n_ptr->routers[r_num / 32] =
((1 << (r_num % 32)) | n_ptr->routers[r_num / 32]);
n_ptr->last_router = tipc_max_nodes / 32;
while ((--n_ptr->last_router >= 0) &&
!n_ptr->routers[n_ptr->last_router]);
}
void node_remove_router(struct node *n_ptr, u32 router)
{
u32 r_num = tipc_node(router);
if (n_ptr->last_router < 0)
return; /* No routes */
n_ptr->routers[r_num / 32] =
((~(1 << (r_num % 32))) & (n_ptr->routers[r_num / 32]));
n_ptr->last_router = tipc_max_nodes / 32;
while ((--n_ptr->last_router >= 0) &&
!n_ptr->routers[n_ptr->last_router]);
if (!node_is_up(n_ptr))
node_lost_contact(n_ptr);
}
#if 0
void node_print(struct print_buf *buf, struct node *n_ptr, char *str)
{
u32 i;
tipc_printf(buf, "\n\n%s", str);
for (i = 0; i < MAX_BEARERS; i++) {
if (!n_ptr->links[i])
continue;
tipc_printf(buf, "Links[%u]: %x, ", i, n_ptr->links[i]);
}
tipc_printf(buf, "Active links: [%x,%x]\n",
n_ptr->active_links[0], n_ptr->active_links[1]);
}
#endif
u32 tipc_available_nodes(const u32 domain)
{
struct node *n_ptr;
u32 cnt = 0;
for (n_ptr = nodes; n_ptr; n_ptr = n_ptr->next) {
if (!in_scope(domain, n_ptr->addr))
continue;
if (node_is_up(n_ptr))
cnt++;
}
return cnt;
}
struct sk_buff *node_get_nodes(const void *req_tlv_area, int req_tlv_space)
{
u32 domain;
struct sk_buff *buf;
struct node *n_ptr;
struct tipc_node_info node_info;
if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
return cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
domain = *(u32 *)TLV_DATA(req_tlv_area);
domain = ntohl(domain);
if (!addr_domain_valid(domain))
return cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
" (network address)");
if (!nodes)
return cfg_reply_none();
/* For now, get space for all other nodes
(will need to modify this when slave nodes are supported */
buf = cfg_reply_alloc(TLV_SPACE(sizeof(node_info)) *
(tipc_max_nodes - 1));
if (!buf)
return NULL;
/* Add TLVs for all nodes in scope */
for (n_ptr = nodes; n_ptr; n_ptr = n_ptr->next) {
if (!in_scope(domain, n_ptr->addr))
continue;
node_info.addr = htonl(n_ptr->addr);
node_info.up = htonl(node_is_up(n_ptr));
cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
&node_info, sizeof(node_info));
}
return buf;
}
struct sk_buff *node_get_links(const void *req_tlv_area, int req_tlv_space)
{
u32 domain;
struct sk_buff *buf;
struct node *n_ptr;
struct tipc_link_info link_info;
if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
return cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
domain = *(u32 *)TLV_DATA(req_tlv_area);
domain = ntohl(domain);
if (!addr_domain_valid(domain))
return cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
" (network address)");
if (!nodes)
return cfg_reply_none();
/* For now, get space for 2 links to all other nodes + bcast link
(will need to modify this when slave nodes are supported */
buf = cfg_reply_alloc(TLV_SPACE(sizeof(link_info)) *
(2 * (tipc_max_nodes - 1) + 1));
if (!buf)
return NULL;
/* Add TLV for broadcast link */
link_info.dest = tipc_own_addr & 0xfffff00;
link_info.dest = htonl(link_info.dest);
link_info.up = htonl(1);
sprintf(link_info.str, bc_link_name);
cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
/* Add TLVs for any other links in scope */
for (n_ptr = nodes; n_ptr; n_ptr = n_ptr->next) {
u32 i;
if (!in_scope(domain, n_ptr->addr))
continue;
for (i = 0; i < MAX_BEARERS; i++) {
if (!n_ptr->links[i])
continue;
link_info.dest = htonl(n_ptr->addr);
link_info.up = htonl(link_is_up(n_ptr->links[i]));
strcpy(link_info.str, n_ptr->links[i]->name);
cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
&link_info, sizeof(link_info));
}
}
return buf;
}
