1 /*
2  * net/tipc/subscr.h: Include file for TIPC network topology service
3  *
4  * Copyright (c) 2003-2017, Ericsson AB
5  * Copyright (c) 2005-2007, 2012-2013, Wind River Systems
6  * Copyright (c) 2020-2021, Red Hat Inc
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the names of the copyright holders nor the names of its
18  *    contributors may be used to endorse or promote products derived from
19  *    this software without specific prior written permission.
20  *
21  * Alternatively, this software may be distributed under the terms of the
22  * GNU General Public License ("GPL") version 2 as published by the Free
23  * Software Foundation.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #ifndef _TIPC_SUBSCR_H
39 #define _TIPC_SUBSCR_H
40 
41 #include "topsrv.h"
42 
43 #define TIPC_MAX_SUBSCR         65535
44 #define TIPC_MAX_PUBL           65535
45 
46 struct publication;
47 struct tipc_subscription;
48 struct tipc_conn;
49 
50 /**
51  * struct tipc_subscription - TIPC network topology subscription object
52  * @s: host-endian copy of the user subscription
53  * @evt: template for events generated by subscription
54  * @kref: reference count for this subscription
55  * @net: network namespace associated with subscription
56  * @timer: timer governing subscription duration (optional)
57  * @service_list: adjacent subscriptions in name sequence's subscription list
58  * @sub_list: adjacent subscriptions in subscriber's subscription list
59  * @conid: connection identifier of topology server
60  * @inactive: true if this subscription is inactive
61  * @lock: serialize up/down and timer events
62  */
63 struct tipc_subscription {
64 	struct tipc_subscr s;
65 	struct tipc_event evt;
66 	struct kref kref;
67 	struct net *net;
68 	struct timer_list timer;
69 	struct list_head service_list;
70 	struct list_head sub_list;
71 	int conid;
72 	bool inactive;
73 	spinlock_t lock;
74 };
75 
76 struct tipc_subscription *tipc_sub_subscribe(struct net *net,
77 					     struct tipc_subscr *s,
78 					     int conid);
79 void tipc_sub_unsubscribe(struct tipc_subscription *sub);
80 void tipc_sub_report_overlap(struct tipc_subscription *sub,
81 			     struct publication *p,
82 			     u32 event, bool must);
83 
84 int __net_init tipc_topsrv_init_net(struct net *net);
85 void __net_exit tipc_topsrv_exit_net(struct net *net);
86 
87 void tipc_sub_put(struct tipc_subscription *subscription);
88 void tipc_sub_get(struct tipc_subscription *subscription);
89 
90 #define TIPC_FILTER_MASK (TIPC_SUB_PORTS | TIPC_SUB_SERVICE | TIPC_SUB_CANCEL)
91 
92 /* tipc_sub_read - return field_ of struct sub_ in host endian format
93  */
94 #define tipc_sub_read(sub_, field_)					\
95 	({								\
96 		struct tipc_subscr *sub__ = sub_;			\
97 		u32 val__ = (sub__)->field_;				\
98 		int swap_ = !((sub__)->filter & TIPC_FILTER_MASK);	\
99 		(swap_ ? swab32(val__) : val__);			\
100 	})
101 
102 /* tipc_sub_write - write val_ to field_ of struct sub_ in user endian format
103  */
104 #define tipc_sub_write(sub_, field_, val_)				\
105 	({								\
106 		struct tipc_subscr *sub__ = sub_;			\
107 		u32 val__ = val_;					\
108 		int swap_ = !((sub__)->filter & TIPC_FILTER_MASK);	\
109 		(sub__)->field_ = swap_ ? swab32(val__) : val__;	\
110 	})
111 
112 /* tipc_evt_write - write val_ to field_ of struct evt_ in user endian format
113  */
114 #define tipc_evt_write(evt_, field_, val_)				\
115 	({								\
116 		struct tipc_event *evt__ = evt_;			\
117 		u32 val__ = val_;					\
118 		int swap_ = !((evt__)->s.filter & (TIPC_FILTER_MASK));	\
119 		(evt__)->field_ = swap_ ? swab32(val__) : val__;	\
120 	})
121 
122 #endif
123