xref: /linux/net/tipc/bearer.h (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /*
2  * net/tipc/bearer.h: Include file for TIPC bearer code
3  *
4  * Copyright (c) 1996-2006, 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 #ifndef _TIPC_BEARER_H
38 #define _TIPC_BEARER_H
39 
40 #include "bcast.h"
41 
42 #define MAX_BEARERS	2
43 #define MAX_MEDIA	2
44 
45 /*
46  * Identifiers associated with TIPC message header media address info
47  *
48  * - address info field is 20 bytes long
49  * - media type identifier located at offset 3
50  * - remaining bytes vary according to media type
51  */
52 #define TIPC_MEDIA_ADDR_SIZE	20
53 #define TIPC_MEDIA_TYPE_OFFSET	3
54 
55 /*
56  * Identifiers of supported TIPC media types
57  */
58 #define TIPC_MEDIA_TYPE_ETH	1
59 
60 /*
61  * struct tipc_media_addr - destination address used by TIPC bearers
62  * @value: address info (format defined by media)
63  * @media_id: TIPC media type identifier
64  * @broadcast: non-zero if address is a broadcast address
65  */
66 struct tipc_media_addr {
67 	u8 value[TIPC_MEDIA_ADDR_SIZE];
68 	u8 media_id;
69 	u8 broadcast;
70 };
71 
72 struct tipc_bearer;
73 
74 /**
75  * struct tipc_media - TIPC media information available to internal users
76  * @send_msg: routine which handles buffer transmission
77  * @enable_bearer: routine which enables a bearer
78  * @disable_bearer: routine which disables a bearer
79  * @addr2str: routine which converts media address to string
80  * @str2addr: routine which converts media address from string
81  * @addr2msg: routine which converts media address to protocol message area
82  * @msg2addr: routine which converts media address from protocol message area
83  * @bcast_addr: media address used in broadcasting
84  * @priority: default link (and bearer) priority
85  * @tolerance: default time (in ms) before declaring link failure
86  * @window: default window (in packets) before declaring link congestion
87  * @type_id: TIPC media identifier
88  * @name: media name
89  */
90 struct tipc_media {
91 	int (*send_msg)(struct sk_buff *buf,
92 			struct tipc_bearer *b_ptr,
93 			struct tipc_media_addr *dest);
94 	int (*enable_bearer)(struct tipc_bearer *b_ptr);
95 	void (*disable_bearer)(struct tipc_bearer *b_ptr);
96 	int (*addr2str)(struct tipc_media_addr *a, char *str_buf, int str_size);
97 	int (*str2addr)(struct tipc_media_addr *a, char *str_buf);
98 	int (*addr2msg)(struct tipc_media_addr *a, char *msg_area);
99 	int (*msg2addr)(struct tipc_media_addr *a, char *msg_area);
100 	struct tipc_media_addr bcast_addr;
101 	u32 priority;
102 	u32 tolerance;
103 	u32 window;
104 	u32 type_id;
105 	char name[TIPC_MAX_MEDIA_NAME];
106 };
107 
108 /**
109  * struct tipc_bearer - TIPC bearer structure
110  * @usr_handle: pointer to additional media-specific information about bearer
111  * @mtu: max packet size bearer can support
112  * @blocked: non-zero if bearer is blocked
113  * @lock: spinlock for controlling access to bearer
114  * @addr: media-specific address associated with bearer
115  * @name: bearer name (format = media:interface)
116  * @media: ptr to media structure associated with bearer
117  * @priority: default link priority for bearer
118  * @window: default window size for bearer
119  * @tolerance: default link tolerance for bearer
120  * @identity: array index of this bearer within TIPC bearer array
121  * @link_req: ptr to (optional) structure making periodic link setup requests
122  * @links: list of non-congested links associated with bearer
123  * @cong_links: list of congested links associated with bearer
124  * @active: non-zero if bearer structure is represents a bearer
125  * @net_plane: network plane ('A' through 'H') currently associated with bearer
126  * @nodes: indicates which nodes in cluster can be reached through bearer
127  *
128  * Note: media-specific code is responsible for initialization of the fields
129  * indicated below when a bearer is enabled; TIPC's generic bearer code takes
130  * care of initializing all other fields.
131  */
132 struct tipc_bearer {
133 	void *usr_handle;			/* initalized by media */
134 	u32 mtu;				/* initalized by media */
135 	int blocked;				/* initalized by media */
136 	struct tipc_media_addr addr;		/* initalized by media */
137 	char name[TIPC_MAX_BEARER_NAME];
138 	spinlock_t lock;
139 	struct tipc_media *media;
140 	u32 priority;
141 	u32 window;
142 	u32 tolerance;
143 	u32 identity;
144 	struct tipc_link_req *link_req;
145 	struct list_head links;
146 	struct list_head cong_links;
147 	int active;
148 	char net_plane;
149 	struct tipc_node_map nodes;
150 };
151 
152 struct tipc_bearer_names {
153 	char media_name[TIPC_MAX_MEDIA_NAME];
154 	char if_name[TIPC_MAX_IF_NAME];
155 };
156 
157 struct tipc_link;
158 
159 extern struct tipc_bearer tipc_bearers[];
160 
161 /*
162  * TIPC routines available to supported media types
163  */
164 int tipc_register_media(struct tipc_media *m_ptr);
165 
166 void tipc_recv_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr);
167 
168 int  tipc_block_bearer(const char *name);
169 void tipc_continue(struct tipc_bearer *tb_ptr);
170 
171 int tipc_enable_bearer(const char *bearer_name, u32 disc_domain, u32 priority);
172 int tipc_disable_bearer(const char *name);
173 
174 /*
175  * Routines made available to TIPC by supported media types
176  */
177 int  tipc_eth_media_start(void);
178 void tipc_eth_media_stop(void);
179 
180 int tipc_media_set_priority(const char *name, u32 new_value);
181 int tipc_media_set_window(const char *name, u32 new_value);
182 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a);
183 struct sk_buff *tipc_media_get_names(void);
184 
185 struct sk_buff *tipc_bearer_get_names(void);
186 void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest);
187 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest);
188 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct tipc_link *l_ptr);
189 struct tipc_bearer *tipc_bearer_find(const char *name);
190 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name);
191 struct tipc_media *tipc_media_find(const char *name);
192 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr,
193 				   struct tipc_link *l_ptr);
194 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct tipc_link *l_ptr);
195 void tipc_bearer_stop(void);
196 void tipc_bearer_lock_push(struct tipc_bearer *b_ptr);
197 
198 
199 /**
200  * tipc_bearer_send- sends buffer to destination over bearer
201  *
202  * Returns true (1) if successful, or false (0) if unable to send
203  *
204  * IMPORTANT:
205  * The media send routine must not alter the buffer being passed in
206  * as it may be needed for later retransmission!
207  *
208  * If the media send routine returns a non-zero value (indicating that
209  * it was unable to send the buffer), it must:
210  *   1) mark the bearer as blocked,
211  *   2) call tipc_continue() once the bearer is able to send again.
212  * Media types that are unable to meet these two critera must ensure their
213  * send routine always returns success -- even if the buffer was not sent --
214  * and let TIPC's link code deal with the undelivered message.
215  */
216 static inline int tipc_bearer_send(struct tipc_bearer *b_ptr,
217 				   struct sk_buff *buf,
218 				   struct tipc_media_addr *dest)
219 {
220 	return !b_ptr->media->send_msg(buf, b_ptr, dest);
221 }
222 
223 #endif	/* _TIPC_BEARER_H */
224