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1/*
2 * net/tipc/net.c: TIPC network routing code
3 *
4 * Copyright (c) 1995-2006, Ericsson AB
5 * Copyright (c) 2005, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
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.
19 *
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
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "net.h"
39#include "name_distr.h"
40#include "subscr.h"
41#include "port.h"
42#include "node.h"
43#include "config.h"
44
45/*
46 * The TIPC locking policy is designed to ensure a very fine locking
47 * granularity, permitting complete parallel access to individual
48 * port and node/link instances. The code consists of three major
49 * locking domains, each protected with their own disjunct set of locks.
50 *
51 * 1: The routing hierarchy.
52 * Comprises the structures 'zone', 'cluster', 'node', 'link'
53 * and 'bearer'. The whole hierarchy is protected by a big
54 * read/write lock, tipc_net_lock, to enssure that nothing is added
55 * or removed while code is accessing any of these structures.
56 * This layer must not be called from the two others while they
57 * hold any of their own locks.
58 * Neither must it itself do any upcalls to the other two before
59 * it has released tipc_net_lock and other protective locks.
60 *
61 * Within the tipc_net_lock domain there are two sub-domains;'node' and
62 * 'bearer', where local write operations are permitted,
63 * provided that those are protected by individual spin_locks
64 * per instance. Code holding tipc_net_lock(read) and a node spin_lock
65 * is permitted to poke around in both the node itself and its
66 * subordinate links. I.e, it can update link counters and queues,
67 * change link state, send protocol messages, and alter the
68 * "active_links" array in the node; but it can _not_ remove a link
69 * or a node from the overall structure.
70 * Correspondingly, individual bearers may change status within a
71 * tipc_net_lock(read), protected by an individual spin_lock ber bearer
72 * instance, but it needs tipc_net_lock(write) to remove/add any bearers.
73 *
74 *
75 * 2: The transport level of the protocol.
76 * This consists of the structures port, (and its user level
77 * representations, such as user_port and tipc_sock), reference and
78 * tipc_user (port.c, reg.c, socket.c).
79 *
80 * This layer has four different locks:
81 * - The tipc_port spin_lock. This is protecting each port instance
82 * from parallel data access and removal. Since we can not place
83 * this lock in the port itself, it has been placed in the
84 * corresponding reference table entry, which has the same life
85 * cycle as the module. This entry is difficult to access from
86 * outside the TIPC core, however, so a pointer to the lock has
87 * been added in the port instance, -to be used for unlocking
88 * only.
89 * - A read/write lock to protect the reference table itself (teg.c).
90 * (Nobody is using read-only access to this, so it can just as
91 * well be changed to a spin_lock)
92 * - A spin lock to protect the registry of kernel/driver users (reg.c)
93 * - A global spin_lock (tipc_port_lock), which only task is to ensure
94 * consistency where more than one port is involved in an operation,
95 * i.e., whe a port is part of a linked list of ports.
96 * There are two such lists; 'port_list', which is used for management,
97 * and 'wait_list', which is used to queue ports during congestion.
98 *
99 * 3: The name table (name_table.c, name_distr.c, subscription.c)
100 * - There is one big read/write-lock (tipc_nametbl_lock) protecting the
101 * overall name table structure. Nothing must be added/removed to
102 * this structure without holding write access to it.
103 * - There is one local spin_lock per sub_sequence, which can be seen
104 * as a sub-domain to the tipc_nametbl_lock domain. It is used only
105 * for translation operations, and is needed because a translation
106 * steps the root of the 'publication' linked list between each lookup.
107 * This is always used within the scope of a tipc_nametbl_lock(read).
108 * - A local spin_lock protecting the queue of subscriber events.
109*/
110
111DEFINE_RWLOCK(tipc_net_lock);
112
113static void net_route_named_msg(struct sk_buff *buf)
114{
115 struct tipc_msg *msg = buf_msg(buf);
116 u32 dnode;
117 u32 dport;
118
119 if (!msg_named(msg)) {
120 kfree_skb(buf);
121 return;
122 }
123
124 dnode = addr_domain(msg_lookup_scope(msg));
125 dport = tipc_nametbl_translate(msg_nametype(msg), msg_nameinst(msg), &dnode);
126 if (dport) {
127 msg_set_destnode(msg, dnode);
128 msg_set_destport(msg, dport);
129 tipc_net_route_msg(buf);
130 return;
131 }
132 tipc_reject_msg(buf, TIPC_ERR_NO_NAME);
133}
134
135void tipc_net_route_msg(struct sk_buff *buf)
136{
137 struct tipc_msg *msg;
138 u32 dnode;
139
140 if (!buf)
141 return;
142 msg = buf_msg(buf);
143
144 /* Handle message for this node */
145 dnode = msg_short(msg) ? tipc_own_addr : msg_destnode(msg);
146 if (tipc_in_scope(dnode, tipc_own_addr)) {
147 if (msg_isdata(msg)) {
148 if (msg_mcast(msg))
149 tipc_port_mcast_rcv(buf, NULL);
150 else if (msg_destport(msg))
151 tipc_port_rcv(buf);
152 else
153 net_route_named_msg(buf);
154 return;
155 }
156 switch (msg_user(msg)) {
157 case NAME_DISTRIBUTOR:
158 tipc_named_rcv(buf);
159 break;
160 case CONN_MANAGER:
161 tipc_port_proto_rcv(buf);
162 break;
163 default:
164 kfree_skb(buf);
165 }
166 return;
167 }
168
169 /* Handle message for another node */
170 skb_trim(buf, msg_size(msg));
171 tipc_link_xmit(buf, dnode, msg_link_selector(msg));
172}
173
174void tipc_net_start(u32 addr)
175{
176 char addr_string[16];
177
178 write_lock_bh(&tipc_net_lock);
179 tipc_own_addr = addr;
180 tipc_named_reinit();
181 tipc_port_reinit();
182 tipc_bclink_init();
183 write_unlock_bh(&tipc_net_lock);
184
185 tipc_nametbl_publish(TIPC_CFG_SRV, tipc_own_addr, tipc_own_addr,
186 TIPC_ZONE_SCOPE, 0, tipc_own_addr);
187 pr_info("Started in network mode\n");
188 pr_info("Own node address %s, network identity %u\n",
189 tipc_addr_string_fill(addr_string, tipc_own_addr), tipc_net_id);
190}
191
192void tipc_net_stop(void)
193{
194 if (!tipc_own_addr)
195 return;
196
197 tipc_nametbl_withdraw(TIPC_CFG_SRV, tipc_own_addr, 0, tipc_own_addr);
198 write_lock_bh(&tipc_net_lock);
199 tipc_bearer_stop();
200 tipc_bclink_stop();
201 tipc_node_stop();
202 write_unlock_bh(&tipc_net_lock);
203
204 pr_info("Left network mode\n");
205}
1/*
2 * net/tipc/net.c: TIPC network routing code
3 *
4 * Copyright (c) 1995-2006, Ericsson AB
5 * Copyright (c) 2005, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
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.
19 *
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
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "net.h"
39#include "name_distr.h"
40#include "subscr.h"
41#include "port.h"
42#include "node.h"
43#include "config.h"
44
45/*
46 * The TIPC locking policy is designed to ensure a very fine locking
47 * granularity, permitting complete parallel access to individual
48 * port and node/link instances. The code consists of three major
49 * locking domains, each protected with their own disjunct set of locks.
50 *
51 * 1: The routing hierarchy.
52 * Comprises the structures 'zone', 'cluster', 'node', 'link'
53 * and 'bearer'. The whole hierarchy is protected by a big
54 * read/write lock, tipc_net_lock, to enssure that nothing is added
55 * or removed while code is accessing any of these structures.
56 * This layer must not be called from the two others while they
57 * hold any of their own locks.
58 * Neither must it itself do any upcalls to the other two before
59 * it has released tipc_net_lock and other protective locks.
60 *
61 * Within the tipc_net_lock domain there are two sub-domains;'node' and
62 * 'bearer', where local write operations are permitted,
63 * provided that those are protected by individual spin_locks
64 * per instance. Code holding tipc_net_lock(read) and a node spin_lock
65 * is permitted to poke around in both the node itself and its
66 * subordinate links. I.e, it can update link counters and queues,
67 * change link state, send protocol messages, and alter the
68 * "active_links" array in the node; but it can _not_ remove a link
69 * or a node from the overall structure.
70 * Correspondingly, individual bearers may change status within a
71 * tipc_net_lock(read), protected by an individual spin_lock ber bearer
72 * instance, but it needs tipc_net_lock(write) to remove/add any bearers.
73 *
74 *
75 * 2: The transport level of the protocol.
76 * This consists of the structures port, (and its user level
77 * representations, such as user_port and tipc_sock), reference and
78 * tipc_user (port.c, reg.c, socket.c).
79 *
80 * This layer has four different locks:
81 * - The tipc_port spin_lock. This is protecting each port instance
82 * from parallel data access and removal. Since we can not place
83 * this lock in the port itself, it has been placed in the
84 * corresponding reference table entry, which has the same life
85 * cycle as the module. This entry is difficult to access from
86 * outside the TIPC core, however, so a pointer to the lock has
87 * been added in the port instance, -to be used for unlocking
88 * only.
89 * - A read/write lock to protect the reference table itself (teg.c).
90 * (Nobody is using read-only access to this, so it can just as
91 * well be changed to a spin_lock)
92 * - A spin lock to protect the registry of kernel/driver users (reg.c)
93 * - A global spin_lock (tipc_port_lock), which only task is to ensure
94 * consistency where more than one port is involved in an operation,
95 * i.e., whe a port is part of a linked list of ports.
96 * There are two such lists; 'port_list', which is used for management,
97 * and 'wait_list', which is used to queue ports during congestion.
98 *
99 * 3: The name table (name_table.c, name_distr.c, subscription.c)
100 * - There is one big read/write-lock (tipc_nametbl_lock) protecting the
101 * overall name table structure. Nothing must be added/removed to
102 * this structure without holding write access to it.
103 * - There is one local spin_lock per sub_sequence, which can be seen
104 * as a sub-domain to the tipc_nametbl_lock domain. It is used only
105 * for translation operations, and is needed because a translation
106 * steps the root of the 'publication' linked list between each lookup.
107 * This is always used within the scope of a tipc_nametbl_lock(read).
108 * - A local spin_lock protecting the queue of subscriber events.
109*/
110
111DEFINE_RWLOCK(tipc_net_lock);
112
113static void net_route_named_msg(struct sk_buff *buf)
114{
115 struct tipc_msg *msg = buf_msg(buf);
116 u32 dnode;
117 u32 dport;
118
119 if (!msg_named(msg)) {
120 buf_discard(buf);
121 return;
122 }
123
124 dnode = addr_domain(msg_lookup_scope(msg));
125 dport = tipc_nametbl_translate(msg_nametype(msg), msg_nameinst(msg), &dnode);
126 if (dport) {
127 msg_set_destnode(msg, dnode);
128 msg_set_destport(msg, dport);
129 tipc_net_route_msg(buf);
130 return;
131 }
132 tipc_reject_msg(buf, TIPC_ERR_NO_NAME);
133}
134
135void tipc_net_route_msg(struct sk_buff *buf)
136{
137 struct tipc_msg *msg;
138 u32 dnode;
139
140 if (!buf)
141 return;
142 msg = buf_msg(buf);
143
144 msg_incr_reroute_cnt(msg);
145 if (msg_reroute_cnt(msg) > 6) {
146 if (msg_errcode(msg)) {
147 buf_discard(buf);
148 } else {
149 tipc_reject_msg(buf, msg_destport(msg) ?
150 TIPC_ERR_NO_PORT : TIPC_ERR_NO_NAME);
151 }
152 return;
153 }
154
155 /* Handle message for this node */
156 dnode = msg_short(msg) ? tipc_own_addr : msg_destnode(msg);
157 if (tipc_in_scope(dnode, tipc_own_addr)) {
158 if (msg_isdata(msg)) {
159 if (msg_mcast(msg))
160 tipc_port_recv_mcast(buf, NULL);
161 else if (msg_destport(msg))
162 tipc_port_recv_msg(buf);
163 else
164 net_route_named_msg(buf);
165 return;
166 }
167 switch (msg_user(msg)) {
168 case NAME_DISTRIBUTOR:
169 tipc_named_recv(buf);
170 break;
171 case CONN_MANAGER:
172 tipc_port_recv_proto_msg(buf);
173 break;
174 default:
175 buf_discard(buf);
176 }
177 return;
178 }
179
180 /* Handle message for another node */
181 skb_trim(buf, msg_size(msg));
182 tipc_link_send(buf, dnode, msg_link_selector(msg));
183}
184
185int tipc_net_start(u32 addr)
186{
187 char addr_string[16];
188 int res;
189
190 if (tipc_mode != TIPC_NODE_MODE)
191 return -ENOPROTOOPT;
192
193 tipc_subscr_stop();
194 tipc_cfg_stop();
195
196 tipc_own_addr = addr;
197 tipc_mode = TIPC_NET_MODE;
198 tipc_named_reinit();
199 tipc_port_reinit();
200
201 res = tipc_bclink_init();
202 if (res)
203 return res;
204
205 tipc_k_signal((Handler)tipc_subscr_start, 0);
206 tipc_k_signal((Handler)tipc_cfg_init, 0);
207
208 info("Started in network mode\n");
209 info("Own node address %s, network identity %u\n",
210 tipc_addr_string_fill(addr_string, tipc_own_addr), tipc_net_id);
211 return 0;
212}
213
214void tipc_net_stop(void)
215{
216 struct tipc_node *node, *t_node;
217
218 if (tipc_mode != TIPC_NET_MODE)
219 return;
220 write_lock_bh(&tipc_net_lock);
221 tipc_bearer_stop();
222 tipc_mode = TIPC_NODE_MODE;
223 tipc_bclink_stop();
224 list_for_each_entry_safe(node, t_node, &tipc_node_list, list)
225 tipc_node_delete(node);
226 write_unlock_bh(&tipc_net_lock);
227 info("Left network mode\n");
228}