/* * net/tipc/net.c: TIPC network routing code * * Copyright (c) 1995-2006, 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 "net.h" #include "name_distr.h" #include "subscr.h" #include "socket.h" #include "node.h" #include "bcast.h" #include "link.h" #include "netlink.h" #include "monitor.h" /* * The TIPC locking policy is designed to ensure a very fine locking * granularity, permitting complete parallel access to individual * port and node/link instances. The code consists of four major * locking domains, each protected with their own disjunct set of locks. * * 1: The bearer level. * RTNL lock is used to serialize the process of configuring bearer * on update side, and RCU lock is applied on read side to make * bearer instance valid on both paths of message transmission and * reception. * * 2: The node and link level. * All node instances are saved into two tipc_node_list and node_htable * lists. The two lists are protected by node_list_lock on write side, * and they are guarded with RCU lock on read side. Especially node * instance is destroyed only when TIPC module is removed, and we can * confirm that there has no any user who is accessing the node at the * moment. Therefore, Except for iterating the two lists within RCU * protection, it's no needed to hold RCU that we access node instance * in other places. * * In addition, all members in node structure including link instances * are protected by node spin lock. * * 3: The transport level of the protocol. * This consists of the structures port, (and its user level * representations, such as user_port and tipc_sock), reference and * tipc_user (port.c, reg.c, socket.c). * * This layer has four different locks: * - The tipc_port spin_lock. This is protecting each port instance * from parallel data access and removal. Since we can not place * this lock in the port itself, it has been placed in the * corresponding reference table entry, which has the same life * cycle as the module. This entry is difficult to access from * outside the TIPC core, however, so a pointer to the lock has * been added in the port instance, -to be used for unlocking * only. * - A read/write lock to protect the reference table itself (teg.c). * (Nobody is using read-only access to this, so it can just as * well be changed to a spin_lock) * - A spin lock to protect the registry of kernel/driver users (reg.c) * - A global spin_lock (tipc_port_lock), which only task is to ensure * consistency where more than one port is involved in an operation, * i.e., when a port is part of a linked list of ports. * There are two such lists; 'port_list', which is used for management, * and 'wait_list', which is used to queue ports during congestion. * * 4: The name table (name_table.c, name_distr.c, subscription.c) * - There is one big read/write-lock (tipc_nametbl_lock) protecting the * overall name table structure. Nothing must be added/removed to * this structure without holding write access to it. * - There is one local spin_lock per sub_sequence, which can be seen * as a sub-domain to the tipc_nametbl_lock domain. It is used only * for translation operations, and is needed because a translation * steps the root of the 'publication' linked list between each lookup. * This is always used within the scope of a tipc_nametbl_lock(read). * - A local spin_lock protecting the queue of subscriber events. */ static void tipc_net_finalize(struct net *net, u32 addr); int tipc_net_init(struct net *net, u8 *node_id, u32 addr) { … } static void tipc_net_finalize(struct net *net, u32 addr) { … } void tipc_net_finalize_work(struct work_struct *work) { … } void tipc_net_stop(struct net *net) { … } static int __tipc_nl_add_net(struct net *net, struct tipc_nl_msg *msg) { … } int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb) { … } int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info) { … } int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info) { … } static int __tipc_nl_addr_legacy_get(struct net *net, struct tipc_nl_msg *msg) { … } int tipc_nl_net_addr_legacy_get(struct sk_buff *skb, struct genl_info *info) { … }