Commit | Line | Data |
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b97bf3fd PL |
1 | /* |
2 | * net/tipc/net.c: TIPC network routing code | |
c4307285 | 3 | * |
5a379074 | 4 | * Copyright (c) 1995-2006, 2014, Ericsson AB |
9df3b7eb | 5 | * Copyright (c) 2005, 2010-2011, Wind River Systems |
b97bf3fd PL |
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 | * | |
9ea1fd3c PL |
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. | |
b97bf3fd PL |
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" | |
b97bf3fd | 38 | #include "net.h" |
b97bf3fd PL |
39 | #include "name_distr.h" |
40 | #include "subscr.h" | |
9816f061 | 41 | #include "socket.h" |
672d99e1 | 42 | #include "node.h" |
b97bf3fd PL |
43 | #include "config.h" |
44 | ||
fd3cf2ad RA |
45 | static const struct nla_policy tipc_nl_net_policy[TIPC_NLA_NET_MAX + 1] = { |
46 | [TIPC_NLA_NET_UNSPEC] = { .type = NLA_UNSPEC }, | |
47 | [TIPC_NLA_NET_ID] = { .type = NLA_U32 } | |
48 | }; | |
49 | ||
c4307285 | 50 | /* |
b97bf3fd PL |
51 | * The TIPC locking policy is designed to ensure a very fine locking |
52 | * granularity, permitting complete parallel access to individual | |
7216cd94 | 53 | * port and node/link instances. The code consists of four major |
b97bf3fd PL |
54 | * locking domains, each protected with their own disjunct set of locks. |
55 | * | |
7216cd94 YX |
56 | * 1: The bearer level. |
57 | * RTNL lock is used to serialize the process of configuring bearer | |
58 | * on update side, and RCU lock is applied on read side to make | |
59 | * bearer instance valid on both paths of message transmission and | |
60 | * reception. | |
b97bf3fd | 61 | * |
7216cd94 YX |
62 | * 2: The node and link level. |
63 | * All node instances are saved into two tipc_node_list and node_htable | |
64 | * lists. The two lists are protected by node_list_lock on write side, | |
65 | * and they are guarded with RCU lock on read side. Especially node | |
66 | * instance is destroyed only when TIPC module is removed, and we can | |
67 | * confirm that there has no any user who is accessing the node at the | |
68 | * moment. Therefore, Except for iterating the two lists within RCU | |
69 | * protection, it's no needed to hold RCU that we access node instance | |
70 | * in other places. | |
b97bf3fd | 71 | * |
7216cd94 YX |
72 | * In addition, all members in node structure including link instances |
73 | * are protected by node spin lock. | |
c4307285 | 74 | * |
7216cd94 YX |
75 | * 3: 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). | |
b97bf3fd | 79 | * |
7216cd94 | 80 | * This layer has four different locks: |
b97bf3fd | 81 | * - The tipc_port spin_lock. This is protecting each port instance |
c4307285 YH |
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 | |
b97bf3fd | 84 | * corresponding reference table entry, which has the same life |
c4307285 YH |
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 | |
b97bf3fd | 88 | * only. |
c4307285 YH |
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 | |
b97bf3fd PL |
91 | * well be changed to a spin_lock) |
92 | * - A spin lock to protect the registry of kernel/driver users (reg.c) | |
c4307285 | 93 | * - A global spin_lock (tipc_port_lock), which only task is to ensure |
b97bf3fd PL |
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. | |
c4307285 | 98 | * |
7216cd94 | 99 | * 4: The name table (name_table.c, name_distr.c, subscription.c) |
c4307285 YH |
100 | * - There is one big read/write-lock (tipc_nametbl_lock) protecting the |
101 | * overall name table structure. Nothing must be added/removed to | |
b97bf3fd PL |
102 | * this structure without holding write access to it. |
103 | * - There is one local spin_lock per sub_sequence, which can be seen | |
4323add6 | 104 | * as a sub-domain to the tipc_nametbl_lock domain. It is used only |
b97bf3fd PL |
105 | * for translation operations, and is needed because a translation |
106 | * steps the root of the 'publication' linked list between each lookup. | |
4323add6 | 107 | * This is always used within the scope of a tipc_nametbl_lock(read). |
b97bf3fd PL |
108 | * - A local spin_lock protecting the queue of subscriber events. |
109 | */ | |
b97bf3fd | 110 | |
eb8b00f5 | 111 | int tipc_net_start(u32 addr) |
b97bf3fd PL |
112 | { |
113 | char addr_string[16]; | |
eb8b00f5 | 114 | int res; |
b97bf3fd | 115 | |
03194379 | 116 | tipc_own_addr = addr; |
4323add6 | 117 | tipc_named_reinit(); |
5a9ee0be | 118 | tipc_sk_reinit(); |
eb8b00f5 YX |
119 | res = tipc_bclink_init(); |
120 | if (res) | |
121 | return res; | |
122 | ||
a5e7ac5c EH |
123 | tipc_nametbl_publish(TIPC_CFG_SRV, tipc_own_addr, tipc_own_addr, |
124 | TIPC_ZONE_SCOPE, 0, tipc_own_addr); | |
7216cd94 | 125 | |
2cf8aa19 EH |
126 | pr_info("Started in network mode\n"); |
127 | pr_info("Own node address %s, network identity %u\n", | |
128 | tipc_addr_string_fill(addr_string, tipc_own_addr), tipc_net_id); | |
eb8b00f5 | 129 | return 0; |
b97bf3fd PL |
130 | } |
131 | ||
4323add6 | 132 | void tipc_net_stop(void) |
b97bf3fd | 133 | { |
b58343f9 | 134 | if (!tipc_own_addr) |
b97bf3fd | 135 | return; |
46651c59 | 136 | |
a5e7ac5c | 137 | tipc_nametbl_withdraw(TIPC_CFG_SRV, tipc_own_addr, 0, tipc_own_addr); |
f97e455a | 138 | rtnl_lock(); |
97f1b625 | 139 | tipc_bearer_stop(); |
4323add6 | 140 | tipc_bclink_stop(); |
46651c59 | 141 | tipc_node_stop(); |
f97e455a | 142 | rtnl_unlock(); |
46651c59 | 143 | |
2cf8aa19 | 144 | pr_info("Left network mode\n"); |
b97bf3fd | 145 | } |
fd3cf2ad RA |
146 | |
147 | static int __tipc_nl_add_net(struct tipc_nl_msg *msg) | |
148 | { | |
149 | void *hdr; | |
150 | struct nlattr *attrs; | |
151 | ||
152 | hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_v2_family, | |
153 | NLM_F_MULTI, TIPC_NL_NET_GET); | |
154 | if (!hdr) | |
155 | return -EMSGSIZE; | |
156 | ||
157 | attrs = nla_nest_start(msg->skb, TIPC_NLA_NET); | |
158 | if (!attrs) | |
159 | goto msg_full; | |
160 | ||
161 | if (nla_put_u32(msg->skb, TIPC_NLA_NET_ID, tipc_net_id)) | |
162 | goto attr_msg_full; | |
163 | ||
164 | nla_nest_end(msg->skb, attrs); | |
165 | genlmsg_end(msg->skb, hdr); | |
166 | ||
167 | return 0; | |
168 | ||
169 | attr_msg_full: | |
170 | nla_nest_cancel(msg->skb, attrs); | |
171 | msg_full: | |
172 | genlmsg_cancel(msg->skb, hdr); | |
173 | ||
174 | return -EMSGSIZE; | |
175 | } | |
176 | ||
177 | int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
178 | { | |
179 | int err; | |
180 | int done = cb->args[0]; | |
181 | struct tipc_nl_msg msg; | |
182 | ||
183 | if (done) | |
184 | return 0; | |
185 | ||
186 | msg.skb = skb; | |
187 | msg.portid = NETLINK_CB(cb->skb).portid; | |
188 | msg.seq = cb->nlh->nlmsg_seq; | |
189 | ||
190 | err = __tipc_nl_add_net(&msg); | |
191 | if (err) | |
192 | goto out; | |
193 | ||
194 | done = 1; | |
195 | out: | |
196 | cb->args[0] = done; | |
197 | ||
198 | return skb->len; | |
199 | } | |
27c21416 RA |
200 | |
201 | int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info) | |
202 | { | |
203 | int err; | |
204 | struct nlattr *attrs[TIPC_NLA_NET_MAX + 1]; | |
205 | ||
206 | if (!info->attrs[TIPC_NLA_NET]) | |
207 | return -EINVAL; | |
208 | ||
209 | err = nla_parse_nested(attrs, TIPC_NLA_NET_MAX, | |
210 | info->attrs[TIPC_NLA_NET], | |
211 | tipc_nl_net_policy); | |
212 | if (err) | |
213 | return err; | |
214 | ||
215 | if (attrs[TIPC_NLA_NET_ID]) { | |
216 | u32 val; | |
217 | ||
218 | /* Can't change net id once TIPC has joined a network */ | |
219 | if (tipc_own_addr) | |
220 | return -EPERM; | |
221 | ||
222 | val = nla_get_u32(attrs[TIPC_NLA_NET_ID]); | |
223 | if (val < 1 || val > 9999) | |
224 | return -EINVAL; | |
225 | ||
226 | tipc_net_id = val; | |
227 | } | |
228 | ||
229 | if (attrs[TIPC_NLA_NET_ADDR]) { | |
230 | u32 addr; | |
231 | ||
232 | /* Can't change net addr once TIPC has joined a network */ | |
233 | if (tipc_own_addr) | |
234 | return -EPERM; | |
235 | ||
236 | addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]); | |
237 | if (!tipc_addr_node_valid(addr)) | |
238 | return -EINVAL; | |
239 | ||
240 | rtnl_lock(); | |
241 | tipc_net_start(addr); | |
242 | rtnl_unlock(); | |
243 | } | |
244 | ||
245 | return 0; | |
246 | } |