/*
* net/tipc/link.h: Include file for TIPC link code
*
* Copyright (c) 1995-2006, Ericsson AB
* Copyright (c) 2004-2005, 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_LINK_H
#define _TIPC_LINK_H
#include "msg.h"
#include "node.h"
/*
* Out-of-range value for link sequence numbers
*/
#define INVALID_LINK_SEQ 0x10000
/*
* Link states
*/
#define WORKING_WORKING 560810u
#define WORKING_UNKNOWN 560811u
#define RESET_UNKNOWN 560812u
#define RESET_RESET 560813u
/*
* Starting value for maximum packet size negotiation on unicast links
* (unless bearer MTU is less)
*/
#define MAX_PKT_DEFAULT 1500
struct tipc_stats {
u32 sent_info; /* used in counting # sent packets */
u32 recv_info; /* used in counting # recv'd packets */
u32 sent_states;
u32 recv_states;
u32 sent_probes;
u32 recv_probes;
u32 sent_nacks;
u32 recv_nacks;
u32 sent_acks;
u32 sent_bundled;
u32 sent_bundles;
u32 recv_bundled;
u32 recv_bundles;
u32 retransmitted;
u32 sent_fragmented;
u32 sent_fragments;
u32 recv_fragmented;
u32 recv_fragments;
u32 link_congs; /* # port sends blocked by congestion */
u32 deferred_recv;
u32 duplicates;
u32 max_queue_sz; /* send queue size high water mark */
u32 accu_queue_sz; /* used for send queue size profiling */
u32 queue_sz_counts; /* used for send queue size profiling */
u32 msg_length_counts; /* used for message length profiling */
u32 msg_lengths_total; /* used for message length profiling */
u32 msg_length_profile[7]; /* used for msg. length profiling */
};
/**
* struct tipc_link - TIPC link data structure
* @addr: network address of link's peer node
* @name: link name character string
* @media_addr: media address to use when sending messages over link
* @timer: link timer
* @owner: pointer to peer node
* @link_list: adjacent links in bearer's list of links
* @started: indicates if link has been started
* @checkpoint: reference point for triggering link continuity checking
* @peer_session: link session # being used by peer end of link
* @peer_bearer_id: bearer id used by link's peer endpoint
* @b_ptr: pointer to bearer used by link
* @tolerance: minimum link continuity loss needed to reset link [in ms]
* @continuity_interval: link continuity testing interval [in ms]
* @abort_limit: # of unacknowledged continuity probes needed to reset link
* @state: current state of link FSM
* @blocked: indicates if link has been administratively blocked
* @fsm_msg_cnt: # of protocol messages link FSM has sent in current state
* @proto_msg: template for control messages generated by link
* @pmsg: convenience pointer to "proto_msg" field
* @priority: current link priority
* @queue_limit: outbound message queue congestion thresholds (indexed by user)
* @exp_msg_count: # of tunnelled messages expected during link changeover
* @reset_checkpoint: seq # of last acknowledged message at time of link reset
* @max_pkt: current maximum packet size for this link
* @max_pkt_target: desired maximum packet size for this link
* @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target)
* @out_queue_size: # of messages in outbound message queue
* @first_out: ptr to first outbound message in queue
* @last_out: ptr to last outbound message in queue
* @next_out_no: next sequence number to use for outbound messages
* @last_retransmitted: sequence number of most recently retransmitted message
* @stale_count: # of identical retransmit requests made by peer
* @next_in_no: next sequence number to expect for inbound messages
* @deferred_inqueue_sz: # of messages in inbound message queue
* @oldest_deferred_in: ptr to first inbound message in queue
* @newest_deferred_in: ptr to last inbound message in queue
* @unacked_window: # of inbound messages rx'd without ack'ing back to peer
* @proto_msg_queue: ptr to (single) outbound control message
* @retransm_queue_size: number of messages to retransmit
* @retransm_queue_head: sequence number of first message to retransmit
* @next_out: ptr to first unsent outbound message in queue
* @waiting_ports: linked list of ports waiting for link congestion to abate
* @long_msg_seq_no: next identifier to use for outbound fragmented messages
* @defragm_buf: list of partially reassembled inbound message fragments
* @stats: collects statistics regarding link activity
*/
struct tipc_link {
u32 addr;
char name[TIPC_MAX_LINK_NAME];
struct tipc_media_addr media_addr;
struct timer_list timer;
struct tipc_node *owner;
struct list_head link_list;
/* Management and link supervision data */
int started;
u32 checkpoint;
u32 peer_session;
u32 peer_bearer_id;
struct tipc_bearer *b_ptr;
u32 tolerance;
u32 continuity_interval;
u32 abort_limit;
int state;
int blocked;
u32 fsm_msg_cnt;
struct {
unchar hdr[INT_H_SIZE];
unchar body[TIPC_MAX_IF_NAME];
} proto_msg;
struct tipc_msg *pmsg;
u32 priority;
u32 queue_limit[15]; /* queue_limit[0]==window limit */
/* Changeover */
u32 exp_msg_count;
u32 reset_checkpoint;
/* Max packet negotiation */
u32 max_pkt;
u32 max_pkt_target;
u32 max_pkt_probes;
/* Sending */
u32 out_queue_size;
struct sk_buff *first_out;
struct sk_buff *last_out;
u32 next_out_no;
u32 last_retransmitted;
u32 stale_count;
/* Reception */
u32 next_in_no;
u32 deferred_inqueue_sz;
struct sk_buff *oldest_deferred_in;
struct sk_buff *newest_deferred_in;
u32 unacked_window;
/* Congestion handling */
struct sk_buff *proto_msg_queue;
u32 retransm_queue_size;
u32 retransm_queue_head;
struct sk_buff *next_out;
struct list_head waiting_ports;
/* Fragmentation/defragmentation */
u32 long_msg_seq_no;
struct sk_buff *defragm_buf;
/* Statistics */
struct tipc_stats stats;
};
struct tipc_port;
struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
struct tipc_bearer *b_ptr,
const struct tipc_media_addr *media_addr);
void tipc_link_delete(struct tipc_link *l_ptr);
void tipc_link_changeover(struct tipc_link *l_ptr);
void tipc_link_send_duplicate(struct tipc_link *l_ptr, struct tipc_link *dest);
void tipc_link_reset_fragments(struct tipc_link *l_ptr);
int tipc_link_is_up(struct tipc_link *l_ptr);
int tipc_link_is_active(struct tipc_link *l_ptr);
u32 tipc_link_push_packet(struct tipc_link *l_ptr);
void tipc_link_stop(struct tipc_link *l_ptr);
struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, u16 cmd);
struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space);
struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space);
void tipc_link_reset(struct tipc_link *l_ptr);
int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector);
void tipc_link_send_names(struct list_head *message_list, u32 dest);
int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf);
u32 tipc_link_get_max_pkt(u32 dest, u32 selector);
int tipc_link_send_sections_fast(struct tipc_port *sender,
struct iovec const *msg_sect,
const u32 num_sect,
unsigned int total_len,
u32 destnode);
void tipc_link_recv_bundle(struct sk_buff *buf);
int tipc_link_recv_fragment(struct sk_buff **pending,
struct sk_buff **fb,
struct tipc_msg **msg);
void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ, int prob,
u32 gap, u32 tolerance, u32 priority,
u32 acked_mtu);
void tipc_link_push_queue(struct tipc_link *l_ptr);
u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
struct sk_buff *buf);
void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all);
void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window);
void tipc_link_retransmit(struct tipc_link *l_ptr,
struct sk_buff *start, u32 retransmits);
/*
* Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
*/
static inline u32 buf_seqno(struct sk_buff *buf)
{
return msg_seqno(buf_msg(buf));
}
static inline u32 mod(u32 x)
{
return x & 0xffffu;
}
static inline int between(u32 lower, u32 upper, u32 n)
{
if ((lower < n) && (n < upper))
return 1;
if ((upper < lower) && ((n > lower) || (n < upper)))
return 1;
return 0;
}
static inline int less_eq(u32 left, u32 right)
{
return mod(right - left) < 32768u;
}
static inline int less(u32 left, u32 right)
{
return less_eq(left, right) && (mod(right) != mod(left));
}
static inline u32 lesser(u32 left, u32 right)
{
return less_eq(left, right) ? left : right;
}
/*
* Link status checking routines
*/
static inline int link_working_working(struct tipc_link *l_ptr)
{
return l_ptr->state == WORKING_WORKING;
}
static inline int link_working_unknown(struct tipc_link *l_ptr)
{
return l_ptr->state == WORKING_UNKNOWN;
}
static inline int link_reset_unknown(struct tipc_link *l_ptr)
{
return l_ptr->state == RESET_UNKNOWN;
}
static inline int link_reset_reset(struct tipc_link *l_ptr)
{
return l_ptr->state == RESET_RESET;
}
static inline int link_blocked(struct tipc_link *l_ptr)
{
return l_ptr->exp_msg_count || l_ptr->blocked;
}
static inline int link_congested(struct tipc_link *l_ptr)
{
return l_ptr->out_queue_size >= l_ptr->queue_limit[0];
}
#endif
