[deliverable/linux.git] / net / tipc / link.h

/*
 * 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 "log.h"
#include "msg.h"
#include "node.h"

#define PUSH_FAILED   1
#define PUSH_FINISHED 2

/*
 * 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 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 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 {
		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 bearer_congs;
		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 */
	} stats;
};

struct tipc_port;

struct 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 link *l_ptr);
void tipc_link_changeover(struct link *l_ptr);
void tipc_link_send_duplicate(struct link *l_ptr, struct link *dest);
void tipc_link_reset_fragments(struct link *l_ptr);
int tipc_link_is_up(struct link *l_ptr);
int tipc_link_is_active(struct link *l_ptr);
u32 tipc_link_push_packet(struct link *l_ptr);
void tipc_link_stop(struct 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 link *l_ptr);
int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector);
int tipc_link_send_buf(struct 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 link *l_ptr, u32 msg_typ, int prob, u32 gap,
			      u32 tolerance, u32 priority, u32 acked_mtu);
void tipc_link_push_queue(struct 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 link *l_ptr, int all);
void tipc_link_set_queue_limits(struct link *l_ptr, u32 window);
void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *start, u32 retransmits);

/*
 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
 */

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 link *l_ptr)
{
	return l_ptr->state == WORKING_WORKING;
}

static inline int link_working_unknown(struct link *l_ptr)
{
	return l_ptr->state == WORKING_UNKNOWN;
}

static inline int link_reset_unknown(struct link *l_ptr)
{
	return l_ptr->state == RESET_UNKNOWN;
}

static inline int link_reset_reset(struct link *l_ptr)
{
	return l_ptr->state == RESET_RESET;
}

static inline int link_blocked(struct link *l_ptr)
{
	return l_ptr->exp_msg_count || l_ptr->blocked;
}

static inline int link_congested(struct link *l_ptr)
{
	return l_ptr->out_queue_size >= l_ptr->queue_limit[0];
}

#endif
Commit	Line	Data
b97bf3fd PL	1	/*
b97bf3fd PL	2	* net/tipc/link.h: Include file for TIPC link code
c4307285	3	*
593a5f22	4	* Copyright (c) 1995-2006, Ericsson AB
23dd4cce	5	* Copyright (c) 2004-2005, 2010-2011, Wind River Systems
b97bf3fd PL	6	* All rights reserved.
b97bf3fd PL	7	*
9ea1fd3c	8	* Redistribution and use in source and binary forms, with or without
b97bf3fd PL	9	* modification, are permitted provided that the following conditions are met:
b97bf3fd PL	10	*
9ea1fd3c PL	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.
b97bf3fd	19	*
9ea1fd3c PL	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
b97bf3fd PL	34	* POSSIBILITY OF SUCH DAMAGE.
	35	*/
	36
	37	#ifndef _TIPC_LINK_H
	38	#define _TIPC_LINK_H
	39
f5e75269	40	#include "log.h"
b97bf3fd	41	#include "msg.h"
b97bf3fd PL	42	#include "node.h"
	43
	44	#define PUSH_FAILED 1
	45	#define PUSH_FINISHED 2
	46
c4307285 YH	47	/*
c4307285 YH	48	* Link states
b97bf3fd PL	49	*/
	50
	51	#define WORKING_WORKING 560810u
	52	#define WORKING_UNKNOWN 560811u
	53	#define RESET_UNKNOWN 560812u
	54	#define RESET_RESET 560813u
	55
c4307285	56	/*
b97bf3fd PL	57	* Starting value for maximum packet size negotiation on unicast links
	58	* (unless bearer MTU is less)
	59	*/
	60
	61	#define MAX_PKT_DEFAULT 1500
	62
	63	/**
	64	* struct link - TIPC link data structure
	65	* @addr: network address of link's peer node
	66	* @name: link name character string
	67	* @media_addr: media address to use when sending messages over link
	68	* @timer: link timer
	69	* @owner: pointer to peer node
	70	* @link_list: adjacent links in bearer's list of links
	71	* @started: indicates if link has been started
	72	* @checkpoint: reference point for triggering link continuity checking
	73	* @peer_session: link session # being used by peer end of link
	74	* @peer_bearer_id: bearer id used by link's peer endpoint
	75	* @b_ptr: pointer to bearer used by link
c4307285	76	* @tolerance: minimum link continuity loss needed to reset link [in ms]
b97bf3fd PL	77	* @continuity_interval: link continuity testing interval [in ms]
	78	* @abort_limit: # of unacknowledged continuity probes needed to reset link
	79	* @state: current state of link FSM
	80	* @blocked: indicates if link has been administratively blocked
	81	* @fsm_msg_cnt: # of protocol messages link FSM has sent in current state
	82	* @proto_msg: template for control messages generated by link
	83	* @pmsg: convenience pointer to "proto_msg" field
	84	* @priority: current link priority
	85	* @queue_limit: outbound message queue congestion thresholds (indexed by user)
	86	* @exp_msg_count: # of tunnelled messages expected during link changeover
	87	* @reset_checkpoint: seq # of last acknowledged message at time of link reset
	88	* @max_pkt: current maximum packet size for this link
	89	* @max_pkt_target: desired maximum packet size for this link
	90	* @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target)
	91	* @out_queue_size: # of messages in outbound message queue
	92	* @first_out: ptr to first outbound message in queue
	93	* @last_out: ptr to last outbound message in queue
	94	* @next_out_no: next sequence number to use for outbound messages
	95	* @last_retransmitted: sequence number of most recently retransmitted message
	96	* @stale_count: # of identical retransmit requests made by peer
	97	* @next_in_no: next sequence number to expect for inbound messages
	98	* @deferred_inqueue_sz: # of messages in inbound message queue
	99	* @oldest_deferred_in: ptr to first inbound message in queue
	100	* @newest_deferred_in: ptr to last inbound message in queue
	101	* @unacked_window: # of inbound messages rx'd without ack'ing back to peer
	102	* @proto_msg_queue: ptr to (single) outbound control message
	103	* @retransm_queue_size: number of messages to retransmit
	104	* @retransm_queue_head: sequence number of first message to retransmit
	105	* @next_out: ptr to first unsent outbound message in queue
	106	* @waiting_ports: linked list of ports waiting for link congestion to abate
	107	* @long_msg_seq_no: next identifier to use for outbound fragmented messages
	108	* @defragm_buf: list of partially reassembled inbound message fragments
	109	* @stats: collects statistics regarding link activity
b97bf3fd	110	*/
c4307285	111
b97bf3fd PL	112	struct link {
	113	u32 addr;
	114	char name[TIPC_MAX_LINK_NAME];
	115	struct tipc_media_addr media_addr;
	116	struct timer_list timer;
6c00055a	117	struct tipc_node *owner;
b97bf3fd PL	118	struct list_head link_list;
	119
	120	/* Management and link supervision data */
	121	int started;
	122	u32 checkpoint;
	123	u32 peer_session;
	124	u32 peer_bearer_id;
2d627b92	125	struct tipc_bearer *b_ptr;
b97bf3fd PL	126	u32 tolerance;
	127	u32 continuity_interval;
	128	u32 abort_limit;
	129	int state;
	130	int blocked;
	131	u32 fsm_msg_cnt;
	132	struct {
	133	unchar hdr[INT_H_SIZE];
	134	unchar body[TIPC_MAX_IF_NAME];
	135	} proto_msg;
	136	struct tipc_msg *pmsg;
	137	u32 priority;
	138	u32 queue_limit[15]; /* queue_limit[0]==window limit */
	139
	140	/* Changeover */
	141	u32 exp_msg_count;
	142	u32 reset_checkpoint;
	143
c4307285 YH	144	/* Max packet negotiation */
	145	u32 max_pkt;
	146	u32 max_pkt_target;
	147	u32 max_pkt_probes;
b97bf3fd PL	148
	149	/* Sending */
	150	u32 out_queue_size;
	151	struct sk_buff *first_out;
	152	struct sk_buff *last_out;
	153	u32 next_out_no;
c4307285 YH	154	u32 last_retransmitted;
c4307285 YH	155	u32 stale_count;
b97bf3fd PL	156
	157	/* Reception */
	158	u32 next_in_no;
	159	u32 deferred_inqueue_sz;
	160	struct sk_buff *oldest_deferred_in;
	161	struct sk_buff *newest_deferred_in;
	162	u32 unacked_window;
	163
	164	/* Congestion handling */
	165	struct sk_buff *proto_msg_queue;
	166	u32 retransm_queue_size;
	167	u32 retransm_queue_head;
	168	struct sk_buff *next_out;
	169	struct list_head waiting_ports;
	170
	171	/* Fragmentation/defragmentation */
	172	u32 long_msg_seq_no;
	173	struct sk_buff *defragm_buf;
	174
c4307285	175	/* Statistics */
b97bf3fd PL	176	struct {
	177	u32 sent_info; /* used in counting # sent packets */
	178	u32 recv_info; /* used in counting # recv'd packets */
	179	u32 sent_states;
	180	u32 recv_states;
	181	u32 sent_probes;
	182	u32 recv_probes;
	183	u32 sent_nacks;
	184	u32 recv_nacks;
	185	u32 sent_acks;
	186	u32 sent_bundled;
	187	u32 sent_bundles;
	188	u32 recv_bundled;
	189	u32 recv_bundles;
	190	u32 retransmitted;
	191	u32 sent_fragmented;
	192	u32 sent_fragments;
	193	u32 recv_fragmented;
	194	u32 recv_fragments;
	195	u32 link_congs; /* # port sends blocked by congestion */
	196	u32 bearer_congs;
	197	u32 deferred_recv;
	198	u32 duplicates;
9bd80b60 AS	199	u32 max_queue_sz; /* send queue size high water mark */
	200	u32 accu_queue_sz; /* used for send queue size profiling */
	201	u32 queue_sz_counts; /* used for send queue size profiling */
	202	u32 msg_length_counts; /* used for message length profiling */
	203	u32 msg_lengths_total; /* used for message length profiling */
	204	u32 msg_length_profile[7]; /* used for msg. length profiling */
b97bf3fd	205	} stats;
b97bf3fd PL	206	};
b97bf3fd PL	207
23dd4cce	208	struct tipc_port;
b97bf3fd	209
37b9c08a AS	210	struct link tipc_link_create(struct tipc_node n_ptr,
37b9c08a AS	211	struct tipc_bearer *b_ptr,
4323add6 PL	212	const struct tipc_media_addr *media_addr);
	213	void tipc_link_delete(struct link *l_ptr);
	214	void tipc_link_changeover(struct link *l_ptr);
	215	void tipc_link_send_duplicate(struct link l_ptr, struct link dest);
	216	void tipc_link_reset_fragments(struct link *l_ptr);
	217	int tipc_link_is_up(struct link *l_ptr);
	218	int tipc_link_is_active(struct link *l_ptr);
4323add6 PL	219	u32 tipc_link_push_packet(struct link *l_ptr);
	220	void tipc_link_stop(struct link *l_ptr);
	221	struct sk_buff tipc_link_cmd_config(const void req_tlv_area, int req_tlv_space, u16 cmd);
	222	struct sk_buff tipc_link_cmd_show_stats(const void req_tlv_area, int req_tlv_space);
	223	struct sk_buff tipc_link_cmd_reset_stats(const void req_tlv_area, int req_tlv_space);
	224	void tipc_link_reset(struct link *l_ptr);
	225	int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector);
	226	int tipc_link_send_buf(struct link l_ptr, struct sk_buff buf);
0e65967e	227	u32 tipc_link_get_max_pkt(u32 dest, u32 selector);
23dd4cce	228	int tipc_link_send_sections_fast(struct tipc_port *sender,
4323add6	229	struct iovec const *msg_sect,
c4307285	230	const u32 num_sect,
26896904	231	unsigned int total_len,
4323add6	232	u32 destnode);
4323add6 PL	233	void tipc_link_recv_bundle(struct sk_buff *buf);
	234	int tipc_link_recv_fragment(struct sk_buff **pending,
	235	struct sk_buff **fb,
	236	struct tipc_msg **msg);
c4307285	237	void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int prob, u32 gap,
4323add6 PL	238	u32 tolerance, u32 priority, u32 acked_mtu);
	239	void tipc_link_push_queue(struct link *l_ptr);
	240	u32 tipc_link_defer_pkt(struct sk_buff head, struct sk_buff tail,
b97bf3fd	241	struct sk_buff *buf);
4323add6 PL	242	void tipc_link_wakeup_ports(struct link *l_ptr, int all);
	243	void tipc_link_set_queue_limits(struct link *l_ptr, u32 window);
	244	void tipc_link_retransmit(struct link l_ptr, struct sk_buff start, u32 retransmits);
b97bf3fd PL	245
	246	/*
	247	* Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
	248	*/
	249
	250	static inline u32 mod(u32 x)
	251	{
	252	return x & 0xffffu;
	253	}
	254
	255	static inline int between(u32 lower, u32 upper, u32 n)
	256	{
	257	if ((lower < n) && (n < upper))
	258	return 1;
	259	if ((upper < lower) && ((n > lower) \|\| (n < upper)))
	260	return 1;
	261	return 0;
	262	}
	263
	264	static inline int less_eq(u32 left, u32 right)
	265	{
a02cec21	266	return mod(right - left) < 32768u;
b97bf3fd PL	267	}
	268
	269	static inline int less(u32 left, u32 right)
	270	{
a02cec21	271	return less_eq(left, right) && (mod(right) != mod(left));
b97bf3fd PL	272	}
	273
	274	static inline u32 lesser(u32 left, u32 right)
	275	{
	276	return less_eq(left, right) ? left : right;
	277	}
	278
01fee256 AS	279
	280	/*
	281	* Link status checking routines
	282	*/
	283
	284	static inline int link_working_working(struct link *l_ptr)
	285	{
a02cec21	286	return l_ptr->state == WORKING_WORKING;
01fee256 AS	287	}
	288
	289	static inline int link_working_unknown(struct link *l_ptr)
	290	{
a02cec21	291	return l_ptr->state == WORKING_UNKNOWN;
01fee256 AS	292	}
	293
	294	static inline int link_reset_unknown(struct link *l_ptr)
	295	{
a02cec21	296	return l_ptr->state == RESET_UNKNOWN;
01fee256 AS	297	}
	298
	299	static inline int link_reset_reset(struct link *l_ptr)
	300	{
a02cec21	301	return l_ptr->state == RESET_RESET;
01fee256 AS	302	}
	303
	304	static inline int link_blocked(struct link *l_ptr)
	305	{
a02cec21	306	return l_ptr->exp_msg_count \|\| l_ptr->blocked;
01fee256 AS	307	}
	308
	309	static inline int link_congested(struct link *l_ptr)
	310	{
a02cec21	311	return l_ptr->out_queue_size >= l_ptr->queue_limit[0];
01fee256 AS	312	}
01fee256 AS	313
b97bf3fd	314	#endif