kernel-aes67/net/tipc/bearer.h
Ying Xue 3c294cb374 tipc: remove the bearer congestion mechanism
Currently at the TIPC bearer layer there is the following congestion
mechanism:

Once sending packets has failed via that bearer, the bearer will be
flagged as being in congested state at once. During bearer congestion,
all packets arriving at link will be queued on the link's outgoing
buffer.  When we detect that the state of bearer congestion has
relaxed (e.g. some packets are received from the bearer) we will try
our best to push all packets in the link's outgoing buffer until the
buffer is empty, or until the bearer is congested again.

However, in fact the TIPC bearer never receives any feedback from the
device layer whether a send was successful or not, so it must always
assume it was successful. Therefore, the bearer congestion mechanism
as it exists currently is of no value.

But the bearer blocking state is still useful for us. For example,
when the physical media goes down/up, we need to change the state of
the links bound to the bearer.  So the code maintaing the state
information is not removed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-11-21 20:07:25 -05:00

206 lines
7.4 KiB
C

/*
* net/tipc/bearer.h: Include file for TIPC bearer code
*
* Copyright (c) 1996-2006, Ericsson AB
* Copyright (c) 2005, 2010-2011, 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 "bcast.h"
#define MAX_BEARERS 2
#define MAX_MEDIA 2
/*
* Identifiers associated with TIPC message header media address info
*
* - address info field is 20 bytes long
* - media type identifier located at offset 3
* - remaining bytes vary according to media type
*/
#define TIPC_MEDIA_ADDR_SIZE 20
#define TIPC_MEDIA_TYPE_OFFSET 3
/*
* Identifiers of supported TIPC media types
*/
#define TIPC_MEDIA_TYPE_ETH 1
/**
* struct tipc_media_addr - destination address used by TIPC bearers
* @value: address info (format defined by media)
* @media_id: TIPC media type identifier
* @broadcast: non-zero if address is a broadcast address
*/
struct tipc_media_addr {
u8 value[TIPC_MEDIA_ADDR_SIZE];
u8 media_id;
u8 broadcast;
};
struct tipc_bearer;
/**
* struct tipc_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 media address to string
* @str2addr: routine which converts media address from string
* @addr2msg: routine which converts media address to protocol message area
* @msg2addr: routine which converts media address from protocol message area
* @bcast_addr: media address used in broadcasting
* @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
* @name: media name
*/
struct tipc_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);
int (*addr2str)(struct tipc_media_addr *a, char *str_buf, int str_size);
int (*str2addr)(struct tipc_media_addr *a, char *str_buf);
int (*addr2msg)(struct tipc_media_addr *a, char *msg_area);
int (*msg2addr)(struct tipc_media_addr *a, char *msg_area);
struct tipc_media_addr bcast_addr;
u32 priority;
u32 tolerance;
u32 window;
u32 type_id;
char name[TIPC_MAX_MEDIA_NAME];
};
/**
* struct tipc_bearer - TIPC bearer structure
* @usr_handle: pointer to additional media-specific information about bearer
* @mtu: max packet size bearer can support
* @blocked: non-zero if bearer is blocked
* @lock: spinlock for controlling access to bearer
* @addr: media-specific address associated with bearer
* @name: bearer name (format = media:interface)
* @media: ptr to media structure associated with bearer
* @priority: default link priority for bearer
* @window: default window size for bearer
* @tolerance: default link tolerance for bearer
* @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
* @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
*
* Note: media-specific code is responsible for initialization of the fields
* indicated below when a bearer is enabled; TIPC's generic bearer code takes
* care of initializing all other fields.
*/
struct tipc_bearer {
void *usr_handle; /* initalized by media */
u32 mtu; /* initalized by media */
int blocked; /* initalized by media */
struct tipc_media_addr addr; /* initalized by media */
char name[TIPC_MAX_BEARER_NAME];
spinlock_t lock;
struct tipc_media *media;
u32 priority;
u32 window;
u32 tolerance;
u32 identity;
struct tipc_link_req *link_req;
struct list_head links;
int active;
char net_plane;
struct tipc_node_map nodes;
};
struct tipc_bearer_names {
char media_name[TIPC_MAX_MEDIA_NAME];
char if_name[TIPC_MAX_IF_NAME];
};
struct tipc_link;
extern struct tipc_bearer tipc_bearers[];
/*
* TIPC routines available to supported media types
*/
int tipc_register_media(struct tipc_media *m_ptr);
void tipc_recv_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr);
int tipc_block_bearer(const char *name);
void tipc_continue(struct tipc_bearer *tb_ptr);
int tipc_enable_bearer(const char *bearer_name, u32 disc_domain, u32 priority);
int tipc_disable_bearer(const char *name);
/*
* Routines made available to TIPC by supported media types
*/
int tipc_eth_media_start(void);
void tipc_eth_media_stop(void);
int tipc_media_set_priority(const char *name, u32 new_value);
int tipc_media_set_window(const char *name, u32 new_value);
void tipc_media_addr_printf(char *buf, int len, 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 tipc_bearer *b_ptr, u32 dest);
void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest);
struct tipc_bearer *tipc_bearer_find(const char *name);
struct tipc_bearer *tipc_bearer_find_interface(const char *if_name);
struct tipc_media *tipc_media_find(const char *name);
int tipc_bearer_blocked(struct tipc_bearer *b_ptr);
void tipc_bearer_stop(void);
/**
* tipc_bearer_send- sends buffer to destination over bearer
*
* IMPORTANT:
* The media send routine must not alter the buffer being passed in
* as it may be needed for later retransmission!
*/
static inline void tipc_bearer_send(struct tipc_bearer *b, struct sk_buff *buf,
struct tipc_media_addr *dest)
{
b->media->send_msg(buf, b, dest);
}
#endif /* _TIPC_BEARER_H */