/*
* 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 tipc_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
