aboutsummaryrefslogtreecommitdiffstats
path: root/net/tipc/bearer.h
blob: 6a36b6600e6c79c7c827eca58061de84e1f7f754 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
/*
 * net/tipc/bearer.h: Include file for TIPC bearer code
 *
 * Copyright (c) 1996-2006, Ericsson AB
 * Copyright (c) 2005, 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.
 */

#ifndef _TIPC_BEARER_H
#define _TIPC_BEARER_H

#include "core.h"
#include "bcast.h"

#define MAX_BEARERS 8
#define MAX_MEDIA 4


/**
 * struct media - TIPC media information available to internal users
 * @send_msg: routine which handles buffer transmission
 * @enable_bearer: routine which enables a bearer
 * @disable_bearer: routine which disables a bearer
 * @addr2str: routine which converts bearer's address to string form
 * @bcast_addr: media address used in broadcasting
 * @bcast: non-zero if media supports broadcasting [currently mandatory]
 * @priority: default link (and bearer) priority
 * @tolerance: default time (in ms) before declaring link failure
 * @window: default window (in packets) before declaring link congestion
 * @type_id: TIPC media identifier [defined in tipc_bearer.h]
 * @name: media name
 */

struct media {
	int (*send_msg)(struct sk_buff *buf,
			struct tipc_bearer *b_ptr,
			struct tipc_media_addr *dest);
	int (*enable_bearer)(struct tipc_bearer *b_ptr);
	void (*disable_bearer)(struct tipc_bearer *b_ptr);
	char *(*addr2str)(struct tipc_media_addr *a,
			  char *str_buf, int str_size);
	struct tipc_media_addr bcast_addr;
	int bcast;
	u32 priority;
	u32 tolerance;
	u32 window;
	u32 type_id;
	char name[TIPC_MAX_MEDIA_NAME];
};

/**
 * struct bearer - TIPC bearer information available to internal users
 * @publ: bearer information available to privileged users
 * @media: ptr to media structure associated with bearer
 * @priority: default link priority for bearer
 * @detect_scope: network address mask used during automatic link creation
 * @identity: array index of this bearer within TIPC bearer array
 * @link_req: ptr to (optional) structure making periodic link setup requests
 * @links: list of non-congested links associated with bearer
 * @cong_links: list of congested links associated with bearer
 * @continue_count: # of times bearer has resumed after congestion or blocking
 * @active: non-zero if bearer structure is represents a bearer
 * @net_plane: network plane ('A' through 'H') currently associated with bearer
 * @nodes: indicates which nodes in cluster can be reached through bearer
 */

struct bearer {
	struct tipc_bearer publ;
	struct media *media;
	u32 priority;
	u32 detect_scope;
	u32 identity;
	struct link_req *link_req;
	struct list_head links;
	struct list_head cong_links;
	u32 continue_count;
	int active;
	char net_plane;
	struct node_map nodes;
};

struct bearer_name {
	char media_name[TIPC_MAX_MEDIA_NAME];
	char if_name[TIPC_MAX_IF_NAME];
};

struct link;

extern struct bearer *tipc_bearers;

void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a);
struct sk_buff *tipc_media_get_names(void);

struct sk_buff *tipc_bearer_get_names(void);
void tipc_bearer_add_dest(struct bearer *b_ptr, u32 dest);
void tipc_bearer_remove_dest(struct bearer *b_ptr, u32 dest);
void tipc_bearer_schedule(struct bearer *b_ptr, struct link *l_ptr);
struct bearer *tipc_bearer_find_interface(const char *if_name);
int tipc_bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr);
int tipc_bearer_init(void);
void tipc_bearer_stop(void);
void tipc_bearer_lock_push(struct bearer *b_ptr);


/**
 * tipc_bearer_send- sends buffer to destination over bearer
 *
 * Returns true (1) if successful, or false (0) if unable to send
 *
 * IMPORTANT:
 * The media send routine must not alter the buffer being passed in
 * as it may be needed for later retransmission!
 *
 * If the media send routine returns a non-zero value (indicating that
 * it was unable to send the buffer), it must:
 *   1) mark the bearer as blocked,
 *   2) call tipc_continue() once the bearer is able to send again.
 * Media types that are unable to meet these two critera must ensure their
 * send routine always returns success -- even if the buffer was not sent --
 * and let TIPC's link code deal with the undelivered message.
 */

static inline int tipc_bearer_send(struct bearer *b_ptr, struct sk_buff *buf,
				   struct tipc_media_addr *dest)
{
	return !b_ptr->media->send_msg(buf, &b_ptr->publ, dest);
}

/**
 * tipc_bearer_congested - determines if bearer is currently congested
 */

static inline int tipc_bearer_congested(struct bearer *b_ptr, struct link *l_ptr)
{
	if (unlikely(b_ptr->publ.blocked))
		return 1;
	if (likely(list_empty(&b_ptr->cong_links)))
		return 0;
	return !tipc_bearer_resolve_congestion(b_ptr, l_ptr);
}

#endif