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 #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(char *buf, int len, 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 */