net/tipc/bearer.h

   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
  53 #define TIPC_MEDIA_ADDR_SIZE    20
  54 #define TIPC_MEDIA_TYPE_OFFSET  3
  55
  56 /*
  57  * Identifiers of supported TIPC media types
  58  */
  59 #define TIPC_MEDIA_TYPE_ETH     1
  60
  61 /*
  62  * struct tipc_media_addr - destination address used by TIPC bearers
  63  * @value: address info (format defined by media)
  64  * @media_id: TIPC media type identifier
  65  * @broadcast: non-zero if address is a broadcast address
  66  */
  67
  68 struct tipc_media_addr {
  69         u8 value[TIPC_MEDIA_ADDR_SIZE];
  70         u8 media_id;
  71         u8 broadcast;
  72 };
  73
  74 struct tipc_bearer;
  75
  76 /**
  77  * struct tipc_media - TIPC media information available to internal users
  78  * @send_msg: routine which handles buffer transmission
  79  * @enable_bearer: routine which enables a bearer
  80  * @disable_bearer: routine which disables a bearer
  81  * @addr2str: routine which converts media address to string
  82  * @str2addr: routine which converts media address from string
  83  * @addr2msg: routine which converts media address to protocol message area
  84  * @msg2addr: routine which converts media address from protocol message area
  85  * @bcast_addr: media address used in broadcasting
  86  * @priority: default link (and bearer) priority
  87  * @tolerance: default time (in ms) before declaring link failure
  88  * @window: default window (in packets) before declaring link congestion
  89  * @type_id: TIPC media identifier
  90  * @name: media name
  91  */
  92
  93 struct tipc_media {
  94         int (*send_msg)(struct sk_buff *buf,
  95                         struct tipc_bearer *b_ptr,
  96                         struct tipc_media_addr *dest);
  97         int (*enable_bearer)(struct tipc_bearer *b_ptr);
  98         void (*disable_bearer)(struct tipc_bearer *b_ptr);
  99         int (*addr2str)(struct tipc_media_addr *a, char *str_buf, int str_size);
 100         int (*str2addr)(struct tipc_media_addr *a, char *str_buf);
 101         int (*addr2msg)(struct tipc_media_addr *a, char *msg_area);
 102         int (*msg2addr)(struct tipc_media_addr *a, char *msg_area);
 103         struct tipc_media_addr bcast_addr;
 104         u32 priority;
 105         u32 tolerance;
 106         u32 window;
 107         u32 type_id;
 108         char name[TIPC_MAX_MEDIA_NAME];
 109 };
 110
 111 /**
 112  * struct tipc_bearer - TIPC bearer structure
 113  * @usr_handle: pointer to additional media-specific information about bearer
 114  * @mtu: max packet size bearer can support
 115  * @blocked: non-zero if bearer is blocked
 116  * @lock: spinlock for controlling access to bearer
 117  * @addr: media-specific address associated with bearer
 118  * @name: bearer name (format = media:interface)
 119  * @media: ptr to media structure associated with bearer
 120  * @priority: default link priority for bearer
 121  * @window: default window size for bearer
 122  * @tolerance: default link tolerance for bearer
 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  * @active: non-zero if bearer structure is represents a bearer
 128  * @net_plane: network plane ('A' through 'H') currently associated with bearer
 129  * @nodes: indicates which nodes in cluster can be reached through bearer
 130  *
 131  * Note: media-specific code is responsible for initialization of the fields
 132  * indicated below when a bearer is enabled; TIPC's generic bearer code takes
 133  * care of initializing all other fields.
 134  */
 135 struct tipc_bearer {
 136         void *usr_handle;                       /* initalized by media */
 137         u32 mtu;                                /* initalized by media */
 138         int blocked;                            /* initalized by media */
 139         struct tipc_media_addr addr;            /* initalized by media */
 140         char name[TIPC_MAX_BEARER_NAME];
 141         spinlock_t lock;
 142         struct tipc_media *media;
 143         u32 priority;
 144         u32 window;
 145         u32 tolerance;
 146         u32 identity;
 147         struct tipc_link_req *link_req;
 148         struct list_head links;
 149         struct list_head cong_links;
 150         int active;
 151         char net_plane;
 152         struct tipc_node_map nodes;
 153 };
 154
 155 struct tipc_bearer_names {
 156         char media_name[TIPC_MAX_MEDIA_NAME];
 157         char if_name[TIPC_MAX_IF_NAME];
 158 };
 159
 160 struct tipc_link;
 161
 162 extern struct tipc_bearer tipc_bearers[];
 163
 164 /*
 165  * TIPC routines available to supported media types
 166  */
 167 int tipc_register_media(struct tipc_media *m_ptr);
 168
 169 void tipc_recv_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr);
 170
 171 int  tipc_block_bearer(const char *name);
 172 void tipc_continue(struct tipc_bearer *tb_ptr);
 173
 174 int tipc_enable_bearer(const char *bearer_name, u32 disc_domain, u32 priority);
 175 int tipc_disable_bearer(const char *name);
 176
 177 /*
 178  * Routines made available to TIPC by supported media types
 179  */
 180 int  tipc_eth_media_start(void);
 181 void tipc_eth_media_stop(void);
 182
 183 int tipc_media_set_priority(const char *name, u32 new_value);
 184 int tipc_media_set_window(const char *name, u32 new_value);
 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 tipc_bearer *b_ptr, u32 dest);
 190 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest);
 191 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct tipc_link *l_ptr);
 192 struct tipc_bearer *tipc_bearer_find(const char *name);
 193 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name);
 194 struct tipc_media *tipc_media_find(const char *name);
 195 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr,
 196                                    struct tipc_link *l_ptr);
 197 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct tipc_link *l_ptr);
 198 void tipc_bearer_stop(void);
 199 void tipc_bearer_lock_push(struct tipc_bearer *b_ptr);
 200
 201
 202 /**
 203  * tipc_bearer_send- sends buffer to destination over bearer
 204  *
 205  * Returns true (1) if successful, or false (0) if unable to send
 206  *
 207  * IMPORTANT:
 208  * The media send routine must not alter the buffer being passed in
 209  * as it may be needed for later retransmission!
 210  *
 211  * If the media send routine returns a non-zero value (indicating that
 212  * it was unable to send the buffer), it must:
 213  *   1) mark the bearer as blocked,
 214  *   2) call tipc_continue() once the bearer is able to send again.
 215  * Media types that are unable to meet these two critera must ensure their
 216  * send routine always returns success -- even if the buffer was not sent --
 217  * and let TIPC's link code deal with the undelivered message.
 218  */
 219
 220 static inline int tipc_bearer_send(struct tipc_bearer *b_ptr,
 221                                    struct sk_buff *buf,
 222                                    struct tipc_media_addr *dest)
 223 {
 224         return !b_ptr->media->send_msg(buf, b_ptr, dest);
 225 }
 226
 227 #endif  /* _TIPC_BEARER_H */