summaryrefslogtreecommitdiffstats
path: root/net/tipc/link.h
blob: 6a51e38ad25c9b027f9852dd5b5d90b9510c1b9b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
/*
 * net/tipc/link.h: Include file for TIPC link code
 *
 * Copyright (c) 1995-2006, Ericsson AB
 * Copyright (c) 2004-2005, 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_LINK_H
#define _TIPC_LINK_H

#include "dbg.h"
#include "msg.h"
#include "bearer.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
 * @print_buf: print buffer used to log 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 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;

		/* for statistical profiling of send queue size */

		u32 max_queue_sz;
		u32 accu_queue_sz;
		u32 queue_sz_counts;

		/* for statistical profiling of message lengths */

		u32 msg_length_counts;
		u32 msg_lengths_total;
		u32 msg_length_profile[7];
#if 0
		u32 sent_tunneled;
		u32 recv_tunneled;
#endif
	} stats;

	struct print_buf print_buf;
};

struct port;

struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
			      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);
void tipc_link_start(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 port* sender,
				 struct iovec const *msg_sect,
				 const u32 num_sect,
				 u32 destnode);
int tipc_link_send_long_buf(struct link *l_ptr, struct sk_buff *buf);
void tipc_link_tunnel(struct link *l_ptr, struct tipc_msg *tnl_hdr,
		      struct tipc_msg *msg, u32 selector);
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;
}

#endif