Select Git revision
node.c 17.87 KiB
/*
* net/tipc/node.c: TIPC node management routines
*
* Copyright (c) 2000-2006, 2012-2014, 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"
#include "socket.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);
struct tipc_sock_conn {
u32 port;
u32 peer_port;
u32 peer_node;
struct list_head list;
};
static const struct nla_policy tipc_nl_node_policy[TIPC_NLA_NODE_MAX + 1] = {
[TIPC_NLA_NODE_UNSPEC] = { .type = NLA_UNSPEC },
[TIPC_NLA_NODE_ADDR] = { .type = NLA_U32 },
[TIPC_NLA_NODE_UP] = { .type = NLA_FLAG }
};
/*
* 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);
INIT_LIST_HEAD(&n_ptr->conn_sks);
__skb_queue_head_init(&n_ptr->waiting_sks);
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->action_flags = TIPC_WAIT_PEER_LINKS_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);
}
int tipc_node_add_conn(u32 dnode, u32 port, u32 peer_port)
{
struct tipc_node *node;
struct tipc_sock_conn *conn;
if (in_own_node(dnode))
return 0;
node = tipc_node_find(dnode);
if (!node) {
pr_warn("Connecting sock to node 0x%x failed\n", dnode);
return -EHOSTUNREACH;
}
conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
if (!conn)
return -EHOSTUNREACH;
conn->peer_node = dnode;
conn->port = port;
conn->peer_port = peer_port;
tipc_node_lock(node);
list_add_tail(&conn->list, &node->conn_sks);
tipc_node_unlock(node);
return 0;
}
void tipc_node_remove_conn(u32 dnode, u32 port)
{
struct tipc_node *node;
struct tipc_sock_conn *conn, *safe;
if (in_own_node(dnode))
return;
node = tipc_node_find(dnode);
if (!node)
return;
tipc_node_lock(node);
list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
if (port != conn->port)
continue;
list_del(&conn->list);
kfree(conn);
}
tipc_node_unlock(node);
}
void tipc_node_abort_sock_conns(struct list_head *conns)
{
struct tipc_sock_conn *conn, *safe;
struct sk_buff *buf;
list_for_each_entry_safe(conn, safe, conns, list) {
buf = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
SHORT_H_SIZE, 0, tipc_own_addr, conn->peer_node, conn->port,
conn->peer_port, TIPC_ERR_NO_NODE);
if (likely(buf))
tipc_sk_rcv(buf);
list_del(&conn->list);
kfree(conn);
}
}
/**
* 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++;
n_ptr->action_flags |= TIPC_NOTIFY_LINK_UP;
n_ptr->link_id = l_ptr->peer_bearer_id << 16 | l_ptr->bearer_id;
pr_info("Established link <%s> on network plane %c\n",
l_ptr->name, l_ptr->net_plane);
if (!active[0]) {
active[0] = active[1] = l_ptr;
node_established_contact(n_ptr);
goto exit;
}
if (l_ptr->priority < active[0]->priority) {
pr_info("New link <%s> becomes standby\n", l_ptr->name);
goto exit;
}
tipc_link_dup_queue_xmit(active[0], l_ptr);
if (l_ptr->priority == active[0]->priority) {
active[0] = l_ptr;
goto exit;
}
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;
exit:
/* Leave room for changeover header when returning 'mtu' to users: */
n_ptr->act_mtus[0] = active[0]->max_pkt - INT_H_SIZE;
n_ptr->act_mtus[1] = active[1]->max_pkt - INT_H_SIZE;
}
/**
* 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--;
n_ptr->action_flags |= TIPC_NOTIFY_LINK_DOWN;
n_ptr->link_id = l_ptr->peer_bearer_id << 16 | l_ptr->bearer_id;
if (!tipc_link_is_active(l_ptr)) {
pr_info("Lost standby link <%s> on network plane %c\n",
l_ptr->name, l_ptr->net_plane);
return;
}
pr_info("Lost link <%s> on network plane %c\n",
l_ptr->name, l_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);
/* Leave room for changeover header when returning 'mtu' to users: */
if (active[0]) {
n_ptr->act_mtus[0] = active[0]->max_pkt - INT_H_SIZE;
n_ptr->act_mtus[1] = active[1]->max_pkt - INT_H_SIZE;
return;
}
/* Loopback link went down? No fragmentation needed from now on. */
if (n_ptr->addr == tipc_own_addr) {
n_ptr->act_mtus[0] = MAX_MSG_SIZE;
n_ptr->act_mtus[1] = MAX_MSG_SIZE;
}
}
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->bearer_id] = 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)
{
n_ptr->action_flags |= TIPC_NOTIFY_NODE_UP;
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_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_buf) {
kfree_skb(n_ptr->bclink.reasm_buf);
n_ptr->bclink.reasm_buf = 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);
}
n_ptr->action_flags &= ~TIPC_WAIT_OWN_LINKS_DOWN;
/* Notify subscribers and prevent re-contact with node until
* cleanup is done.
*/
n_ptr->action_flags |= TIPC_WAIT_PEER_LINKS_DOWN |
TIPC_NOTIFY_NODE_DOWN;
}
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;
}
/**
* tipc_node_get_linkname - get the name of a link
*
* @bearer_id: id of the bearer
* @node: peer node address
* @linkname: link name output buffer
*
* Returns 0 on success
*/
int tipc_node_get_linkname(u32 bearer_id, u32 addr, char *linkname, size_t len)
{
struct tipc_link *link;
struct tipc_node *node = tipc_node_find(addr);
if ((bearer_id >= MAX_BEARERS) || !node)
return -EINVAL;
tipc_node_lock(node);
link = node->links[bearer_id];
if (link) {
strncpy(linkname, link->name, len);
tipc_node_unlock(node);
return 0;
}
tipc_node_unlock(node);
return -EINVAL;
}
void tipc_node_unlock(struct tipc_node *node)
{
LIST_HEAD(nsub_list);
LIST_HEAD(conn_sks);
struct sk_buff_head waiting_sks;
u32 addr = 0; int flags = node->action_flags;
u32 link_id = 0;
if (likely(!flags)) {
spin_unlock_bh(&node->lock);
return;
}
addr = node->addr;
link_id = node->link_id;
__skb_queue_head_init(&waiting_sks);
if (flags & TIPC_WAKEUP_USERS)
skb_queue_splice_init(&node->waiting_sks, &waiting_sks);
if (flags & TIPC_NOTIFY_NODE_DOWN) {
list_replace_init(&node->nsub, &nsub_list);
list_replace_init(&node->conn_sks, &conn_sks);
}
node->action_flags &= ~(TIPC_WAKEUP_USERS | TIPC_NOTIFY_NODE_DOWN |
TIPC_NOTIFY_NODE_UP | TIPC_NOTIFY_LINK_UP |
TIPC_NOTIFY_LINK_DOWN |
TIPC_WAKEUP_BCAST_USERS);
spin_unlock_bh(&node->lock);
while (!skb_queue_empty(&waiting_sks))
tipc_sk_rcv(__skb_dequeue(&waiting_sks));
if (!list_empty(&conn_sks))
tipc_node_abort_sock_conns(&conn_sks);
if (!list_empty(&nsub_list))
tipc_nodesub_notify(&nsub_list);
if (flags & TIPC_WAKEUP_BCAST_USERS)
tipc_bclink_wakeup_users();
if (flags & TIPC_NOTIFY_NODE_UP)
tipc_named_node_up(addr);
if (flags & TIPC_NOTIFY_LINK_UP)
tipc_nametbl_publish(TIPC_LINK_STATE, addr, addr,
TIPC_NODE_SCOPE, link_id, addr);
if (flags & TIPC_NOTIFY_LINK_DOWN)
tipc_nametbl_withdraw(TIPC_LINK_STATE, addr,
link_id, addr);
}
/* Caller should hold node lock for the passed node */
int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
{
void *hdr;
struct nlattr *attrs;
hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_v2_family,
NLM_F_MULTI, TIPC_NL_NODE_GET);
if (!hdr)
return -EMSGSIZE;
attrs = nla_nest_start(msg->skb, TIPC_NLA_NODE);
if (!attrs)
goto msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
goto attr_msg_full;
if (tipc_node_is_up(node))
if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
goto attr_msg_full;
nla_nest_end(msg->skb, attrs);
genlmsg_end(msg->skb, hdr);
return 0;
attr_msg_full:
nla_nest_cancel(msg->skb, attrs);
msg_full:
genlmsg_cancel(msg->skb, hdr);
return -EMSGSIZE;
}
int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
int err;
int done = cb->args[0];
int last_addr = cb->args[1];
struct tipc_node *node;
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();
if (last_addr && !tipc_node_find(last_addr)) {
rcu_read_unlock();
/* 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
* the node state changed while we released the lock.
*/
cb->prev_seq = 1;
return -EPIPE;
}
list_for_each_entry_rcu(node, &tipc_node_list, list) {
if (last_addr) {
if (node->addr == last_addr)
last_addr = 0;
else
continue;
}
tipc_node_lock(node);
err = __tipc_nl_add_node(&msg, node);
if (err) {
last_addr = node->addr;
tipc_node_unlock(node);
goto out;
}
tipc_node_unlock(node);
}
done = 1;
out:
cb->args[0] = done;
cb->args[1] = last_addr;
rcu_read_unlock();
return skb->len;
}