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 "core.h" 41 #include "bcast.h" 42 43 #define MAX_BEARERS 8 44 #define MAX_MEDIA 4 45 46 47 /** 48 * struct media - TIPC media information available to internal users 49 * @send_msg: routine which handles buffer transmission 50 * @enable_bearer: routine which enables a bearer 51 * @disable_bearer: routine which disables a bearer 52 * @addr2str: routine which converts bearer's address to string form 53 * @bcast_addr: media address used in broadcasting 54 * @bcast: non-zero if media supports broadcasting [currently mandatory] 55 * @priority: default link (and bearer) priority 56 * @tolerance: default time (in ms) before declaring link failure 57 * @window: default window (in packets) before declaring link congestion 58 * @type_id: TIPC media identifier [defined in tipc_bearer.h] 59 * @name: media name 60 */ 61 62 struct media { 63 int (*send_msg)(struct sk_buff *buf, 64 struct tipc_bearer *b_ptr, 65 struct tipc_media_addr *dest); 66 int (*enable_bearer)(struct tipc_bearer *b_ptr); 67 void (*disable_bearer)(struct tipc_bearer *b_ptr); 68 char *(*addr2str)(struct tipc_media_addr *a, 69 char *str_buf, int str_size); 70 struct tipc_media_addr bcast_addr; 71 int bcast; 72 u32 priority; 73 u32 tolerance; 74 u32 window; 75 u32 type_id; 76 char name[TIPC_MAX_MEDIA_NAME]; 77 }; 78 79 /** 80 * struct bearer - TIPC bearer information available to internal users 81 * @publ: bearer information available to privileged users 82 * @media: ptr to media structure associated with bearer 83 * @priority: default link priority for bearer 84 * @detect_scope: network address mask used during automatic link creation 85 * @identity: array index of this bearer within TIPC bearer array 86 * @link_req: ptr to (optional) structure making periodic link setup requests 87 * @links: list of non-congested links associated with bearer 88 * @cong_links: list of congested links associated with bearer 89 * @continue_count: # of times bearer has resumed after congestion or blocking 90 * @active: non-zero if bearer structure is represents a bearer 91 * @net_plane: network plane ('A' through 'H') currently associated with bearer 92 * @nodes: indicates which nodes in cluster can be reached through bearer 93 */ 94 95 struct bearer { 96 struct tipc_bearer publ; 97 struct media *media; 98 u32 priority; 99 u32 detect_scope; 100 u32 identity; 101 struct link_req *link_req; 102 struct list_head links; 103 struct list_head cong_links; 104 u32 continue_count; 105 int active; 106 char net_plane; 107 struct tipc_node_map nodes; 108 }; 109 110 struct bearer_name { 111 char media_name[TIPC_MAX_MEDIA_NAME]; 112 char if_name[TIPC_MAX_IF_NAME]; 113 }; 114 115 struct link; 116 117 extern struct bearer *tipc_bearers; 118 119 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a); 120 struct sk_buff *tipc_media_get_names(void); 121 122 struct sk_buff *tipc_bearer_get_names(void); 123 void tipc_bearer_add_dest(struct bearer *b_ptr, u32 dest); 124 void tipc_bearer_remove_dest(struct bearer *b_ptr, u32 dest); 125 void tipc_bearer_schedule(struct bearer *b_ptr, struct link *l_ptr); 126 struct bearer *tipc_bearer_find_interface(const char *if_name); 127 int tipc_bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr); 128 int tipc_bearer_init(void); 129 void tipc_bearer_stop(void); 130 void tipc_bearer_lock_push(struct bearer *b_ptr); 131 132 133 /** 134 * tipc_bearer_send- sends buffer to destination over bearer 135 * 136 * Returns true (1) if successful, or false (0) if unable to send 137 * 138 * IMPORTANT: 139 * The media send routine must not alter the buffer being passed in 140 * as it may be needed for later retransmission! 141 * 142 * If the media send routine returns a non-zero value (indicating that 143 * it was unable to send the buffer), it must: 144 * 1) mark the bearer as blocked, 145 * 2) call tipc_continue() once the bearer is able to send again. 146 * Media types that are unable to meet these two critera must ensure their 147 * send routine always returns success -- even if the buffer was not sent -- 148 * and let TIPC's link code deal with the undelivered message. 149 */ 150 151 static inline int tipc_bearer_send(struct bearer *b_ptr, struct sk_buff *buf, 152 struct tipc_media_addr *dest) 153 { 154 return !b_ptr->media->send_msg(buf, &b_ptr->publ, dest); 155 } 156 157 /** 158 * tipc_bearer_congested - determines if bearer is currently congested 159 */ 160 161 static inline int tipc_bearer_congested(struct bearer *b_ptr, struct link *l_ptr) 162 { 163 if (unlikely(b_ptr->publ.blocked)) 164 return 1; 165 if (likely(list_empty(&b_ptr->cong_links))) 166 return 0; 167 return !tipc_bearer_resolve_congestion(b_ptr, l_ptr); 168 } 169 170 #endif 171