xref: /openbmc/linux/net/tipc/bearer.h (revision 4800cd83)
1 /*
2  * net/tipc/bearer.h: Include file for TIPC bearer code
3  *
4  * Copyright (c) 1996-2006, Ericsson AB
5  * Copyright (c) 2005, 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 8
43 #define MAX_MEDIA 4
44 
45 /*
46  * Identifiers of supported TIPC media types
47  */
48 #define TIPC_MEDIA_TYPE_ETH	1
49 
50 /*
51  * Destination address structure used by TIPC bearers when sending messages
52  *
53  * IMPORTANT: The fields of this structure MUST be stored using the specified
54  * byte order indicated below, as the structure is exchanged between nodes
55  * as part of a link setup process.
56  */
57 struct tipc_media_addr {
58 	__be32  type;			/* bearer type (network byte order) */
59 	union {
60 		__u8   eth_addr[6];	/* 48 bit Ethernet addr (byte array) */
61 	} dev_addr;
62 };
63 
64 /**
65  * struct tipc_bearer - TIPC bearer info available to media code
66  * @usr_handle: pointer to additional media-specific information about bearer
67  * @mtu: max packet size bearer can support
68  * @blocked: non-zero if bearer is blocked
69  * @lock: spinlock for controlling access to bearer
70  * @addr: media-specific address associated with bearer
71  * @name: bearer name (format = media:interface)
72  *
73  * Note: TIPC initializes "name" and "lock" fields; media code is responsible
74  * for initialization all other fields when a bearer is enabled.
75  */
76 struct tipc_bearer {
77 	void *usr_handle;
78 	u32 mtu;
79 	int blocked;
80 	spinlock_t lock;
81 	struct tipc_media_addr addr;
82 	char name[TIPC_MAX_BEARER_NAME];
83 };
84 
85 /**
86  * struct media - TIPC media information available to internal users
87  * @send_msg: routine which handles buffer transmission
88  * @enable_bearer: routine which enables a bearer
89  * @disable_bearer: routine which disables a bearer
90  * @addr2str: routine which converts bearer's address to string form
91  * @bcast_addr: media address used in broadcasting
92  * @bcast: non-zero if media supports broadcasting [currently mandatory]
93  * @priority: default link (and bearer) priority
94  * @tolerance: default time (in ms) before declaring link failure
95  * @window: default window (in packets) before declaring link congestion
96  * @type_id: TIPC media identifier
97  * @name: media name
98  */
99 
100 struct media {
101 	int (*send_msg)(struct sk_buff *buf,
102 			struct tipc_bearer *b_ptr,
103 			struct tipc_media_addr *dest);
104 	int (*enable_bearer)(struct tipc_bearer *b_ptr);
105 	void (*disable_bearer)(struct tipc_bearer *b_ptr);
106 	char *(*addr2str)(struct tipc_media_addr *a,
107 			  char *str_buf, int str_size);
108 	struct tipc_media_addr bcast_addr;
109 	int bcast;
110 	u32 priority;
111 	u32 tolerance;
112 	u32 window;
113 	u32 type_id;
114 	char name[TIPC_MAX_MEDIA_NAME];
115 };
116 
117 /**
118  * struct bearer - TIPC bearer information available to internal users
119  * @publ: bearer information available to privileged users
120  * @media: ptr to media structure associated with bearer
121  * @priority: default link priority for bearer
122  * @detect_scope: network address mask used during automatic link creation
123  * @identity: array index of this bearer within TIPC bearer array
124  * @link_req: ptr to (optional) structure making periodic link setup requests
125  * @links: list of non-congested links associated with bearer
126  * @cong_links: list of congested links associated with bearer
127  * @continue_count: # of times bearer has resumed after congestion or blocking
128  * @active: non-zero if bearer structure is represents a bearer
129  * @net_plane: network plane ('A' through 'H') currently associated with bearer
130  * @nodes: indicates which nodes in cluster can be reached through bearer
131  */
132 
133 struct bearer {
134 	struct tipc_bearer publ;
135 	struct media *media;
136 	u32 priority;
137 	u32 detect_scope;
138 	u32 identity;
139 	struct link_req *link_req;
140 	struct list_head links;
141 	struct list_head cong_links;
142 	u32 continue_count;
143 	int active;
144 	char net_plane;
145 	struct tipc_node_map nodes;
146 };
147 
148 struct bearer_name {
149 	char media_name[TIPC_MAX_MEDIA_NAME];
150 	char if_name[TIPC_MAX_IF_NAME];
151 };
152 
153 struct link;
154 
155 extern struct bearer tipc_bearers[];
156 
157 /*
158  * TIPC routines available to supported media types
159  */
160 int tipc_register_media(u32 media_type,
161 		 char *media_name, int (*enable)(struct tipc_bearer *),
162 		 void (*disable)(struct tipc_bearer *),
163 		 int (*send_msg)(struct sk_buff *,
164 			struct tipc_bearer *, struct tipc_media_addr *),
165 		 char *(*addr2str)(struct tipc_media_addr *a,
166 			char *str_buf, int str_size),
167 		 struct tipc_media_addr *bcast_addr, const u32 bearer_priority,
168 		 const u32 link_tolerance,  /* [ms] */
169 		 const u32 send_window_limit);
170 
171 void tipc_recv_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr);
172 
173 int  tipc_block_bearer(const char *name);
174 void tipc_continue(struct tipc_bearer *tb_ptr);
175 
176 int tipc_enable_bearer(const char *bearer_name, u32 bcast_scope, u32 priority);
177 int tipc_disable_bearer(const char *name);
178 
179 /*
180  * Routines made available to TIPC by supported media types
181  */
182 int  tipc_eth_media_start(void);
183 void tipc_eth_media_stop(void);
184 
185 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a);
186 struct sk_buff *tipc_media_get_names(void);
187 
188 struct sk_buff *tipc_bearer_get_names(void);
189 void tipc_bearer_add_dest(struct bearer *b_ptr, u32 dest);
190 void tipc_bearer_remove_dest(struct bearer *b_ptr, u32 dest);
191 void tipc_bearer_schedule(struct bearer *b_ptr, struct link *l_ptr);
192 struct bearer *tipc_bearer_find_interface(const char *if_name);
193 int tipc_bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr);
194 int tipc_bearer_congested(struct bearer *b_ptr, struct link *l_ptr);
195 void tipc_bearer_stop(void);
196 void tipc_bearer_lock_push(struct 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 
217 static inline int tipc_bearer_send(struct bearer *b_ptr, struct sk_buff *buf,
218 				   struct tipc_media_addr *dest)
219 {
220 	return !b_ptr->media->send_msg(buf, &b_ptr->publ, dest);
221 }
222 
223 #endif	/* _TIPC_BEARER_H */
224