aboutsummaryrefslogtreecommitdiffstats
path: root/net/rxrpc/connection.c
blob: 2ba14a75dbbeb94c37d196b4501bbe6025c1ac69 (plain) (blame)
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
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
/* connection.c: Rx connection routines
 *
 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <rxrpc/rxrpc.h>
#include <rxrpc/transport.h>
#include <rxrpc/peer.h>
#include <rxrpc/connection.h>
#include <rxrpc/call.h>
#include <rxrpc/message.h>
#include <linux/udp.h>
#include <linux/ip.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include "internal.h"

__RXACCT_DECL(atomic_t rxrpc_connection_count);

LIST_HEAD(rxrpc_conns);
DECLARE_RWSEM(rxrpc_conns_sem);
unsigned long rxrpc_conn_timeout = 60 * 60;

static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn);

static void __rxrpc_conn_timeout(rxrpc_timer_t *timer)
{
	struct rxrpc_connection *conn =
		list_entry(timer, struct rxrpc_connection, timeout);

	_debug("Rx CONN TIMEOUT [%p{u=%d}]", conn, atomic_read(&conn->usage));

	rxrpc_conn_do_timeout(conn);
}

static const struct rxrpc_timer_ops rxrpc_conn_timer_ops = {
	.timed_out	= __rxrpc_conn_timeout,
};

/*****************************************************************************/
/*
 * create a new connection record
 */
static inline int __rxrpc_create_connection(struct rxrpc_peer *peer,
					    struct rxrpc_connection **_conn)
{
	struct rxrpc_connection *conn;

	_enter("%p",peer);

	/* allocate and initialise a connection record */
	conn = kmalloc(sizeof(struct rxrpc_connection), GFP_KERNEL);
	if (!conn) {
		_leave(" = -ENOMEM");
		return -ENOMEM;
	}

	memset(conn, 0, sizeof(struct rxrpc_connection));
	atomic_set(&conn->usage, 1);

	INIT_LIST_HEAD(&conn->link);
	INIT_LIST_HEAD(&conn->id_link);
	init_waitqueue_head(&conn->chanwait);
	spin_lock_init(&conn->lock);
	rxrpc_timer_init(&conn->timeout, &rxrpc_conn_timer_ops);

	do_gettimeofday(&conn->atime);
	conn->mtu_size = 1024;
	conn->peer = peer;
	conn->trans = peer->trans;

	__RXACCT(atomic_inc(&rxrpc_connection_count));
	*_conn = conn;
	_leave(" = 0 (%p)", conn);

	return 0;
} /* end __rxrpc_create_connection() */

/*****************************************************************************/
/*
 * create a new connection record for outgoing connections
 */
int rxrpc_create_connection(struct rxrpc_transport *trans,
			    __be16 port,
			    __be32 addr,
			    uint16_t service_id,
			    void *security,
			    struct rxrpc_connection **_conn)
{
	struct rxrpc_connection *candidate, *conn;
	struct rxrpc_peer *peer;
	struct list_head *_p;
	__be32 connid;
	int ret;

	_enter("%p{%hu},%u,%hu", trans, trans->port, ntohs(port), service_id);

	/* get a peer record */
	ret = rxrpc_peer_lookup(trans, addr, &peer);
	if (ret < 0) {
		_leave(" = %d", ret);
		return ret;
	}

	/* allocate and initialise a connection record */
	ret = __rxrpc_create_connection(peer, &candidate);
	if (ret < 0) {
		rxrpc_put_peer(peer);
		_leave(" = %d", ret);
		return ret;
	}

	/* fill in the specific bits */
	candidate->addr.sin_family	= AF_INET;
	candidate->addr.sin_port	= port;
	candidate->addr.sin_addr.s_addr	= addr;

	candidate->in_epoch		= rxrpc_epoch;
	candidate->out_epoch		= rxrpc_epoch;
	candidate->in_clientflag	= 0;
	candidate->out_clientflag	= RXRPC_CLIENT_INITIATED;
	candidate->service_id		= htons(service_id);

	/* invent a unique connection ID */
	write_lock(&peer->conn_idlock);

 try_next_id:
	connid = htonl(peer->conn_idcounter & RXRPC_CIDMASK);
	peer->conn_idcounter += RXRPC_MAXCALLS;

	list_for_each(_p, &peer->conn_idlist) {
		conn = list_entry(_p, struct rxrpc_connection, id_link);
		if (connid == conn->conn_id)
			goto try_next_id;
		if (connid > conn->conn_id)
			break;
	}

	_debug("selected candidate conn ID %x.%u",
	       ntohl(peer->addr.s_addr), ntohl(connid));

	candidate->conn_id = connid;
	list_add_tail(&candidate->id_link, _p);

	write_unlock(&peer->conn_idlock);

	/* attach to peer */
	candidate->peer = peer;

	write_lock(&peer->conn_lock);

	/* search the peer's transport graveyard list */
	spin_lock(&peer->conn_gylock);
	list_for_each(_p, &peer->conn_graveyard) {
		conn = list_entry(_p, struct rxrpc_connection, link);
		if (conn->addr.sin_port	== candidate->addr.sin_port	&&
		    conn->security_ix	== candidate->security_ix	&&
		    conn->service_id	== candidate->service_id	&& 
		    conn->in_clientflag	== 0)
			goto found_in_graveyard;
	}
	spin_unlock(&peer->conn_gylock);

	/* pick the new candidate */
	_debug("created connection: {%08x} [out]", ntohl(candidate->conn_id));
	atomic_inc(&peer->conn_count);
	conn = candidate;
	candidate = NULL;

 make_active:
	list_add_tail(&conn->link, &peer->conn_active);
	write_unlock(&peer->conn_lock);

	if (candidate) {
		write_lock(&peer->conn_idlock);
		list_del(&candidate->id_link);
		write_unlock(&peer->conn_idlock);

		__RXACCT(atomic_dec(&rxrpc_connection_count));
		kfree(candidate);
	}
	else {
		down_write(&rxrpc_conns_sem);
		list_add_tail(&conn->proc_link, &rxrpc_conns);
		up_write(&rxrpc_conns_sem);
	}

	*_conn = conn;
	_leave(" = 0 (%p)", conn);

	return 0;

	/* handle resurrecting a connection from the graveyard */
 found_in_graveyard:
	_debug("resurrecting connection: {%08x} [out]", ntohl(conn->conn_id));
	rxrpc_get_connection(conn);
	rxrpc_krxtimod_del_timer(&conn->timeout);
	list_del_init(&conn->link);
	spin_unlock(&peer->conn_gylock);
	goto make_active;
} /* end rxrpc_create_connection() */

/*****************************************************************************/
/*
 * lookup the connection for an incoming packet
 * - create a new connection record for unrecorded incoming connections
 */
int rxrpc_connection_lookup(struct rxrpc_peer *peer,
			    struct rxrpc_message *msg,
			    struct rxrpc_connection **_conn)
{
	struct rxrpc_connection *conn, *candidate = NULL;
	struct list_head *_p;
	int ret, fresh = 0;
	__be32 x_epoch, x_connid;
	__be16 x_port, x_servid;
	__u32 x_secix;
	u8 x_clflag;

	_enter("%p{{%hu}},%u,%hu",
	       peer,
	       peer->trans->port,
	       ntohs(msg->pkt->h.uh->source),
	       ntohs(msg->hdr.serviceId));

	x_port		= msg->pkt->h.uh->source;
	x_epoch		= msg->hdr.epoch;
	x_clflag	= msg->hdr.flags & RXRPC_CLIENT_INITIATED;
	x_connid	= htonl(ntohl(msg->hdr.cid) & RXRPC_CIDMASK);
	x_servid	= msg->hdr.serviceId;
	x_secix		= msg->hdr.securityIndex;

	/* [common case] search the transport's active list first */
	read_lock(&peer->conn_lock);
	list_for_each(_p, &peer->conn_active) {
		conn = list_entry(_p, struct rxrpc_connection, link);
		if (conn->addr.sin_port		== x_port	&&
		    conn->in_epoch		== x_epoch	&&
		    conn->conn_id		== x_connid	&&
		    conn->security_ix		== x_secix	&&
		    conn->service_id		== x_servid	&& 
		    conn->in_clientflag		== x_clflag)
			goto found_active;
	}
	read_unlock(&peer->conn_lock);

	/* [uncommon case] not active 
	 * - create a candidate for a new record if an inbound connection
	 * - only examine the graveyard for an outbound connection
	 */
	if (x_clflag) {
		ret = __rxrpc_create_connection(peer, &candidate);
		if (ret < 0) {
			_leave(" = %d", ret);
			return ret;
		}

		/* fill in the specifics */
		candidate->addr.sin_family	= AF_INET;
		candidate->addr.sin_port	= x_port;
		candidate->addr.sin_addr.s_addr = msg->pkt->nh.iph->saddr;
		candidate->in_epoch		= x_epoch;
		candidate->out_epoch		= x_epoch;
		candidate->in_clientflag	= RXRPC_CLIENT_INITIATED;
		candidate->out_clientflag	= 0;
		candidate->conn_id		= x_connid;
		candidate->service_id		= x_servid;
		candidate->security_ix		= x_secix;
	}

	/* search the active list again, just in case it appeared whilst we
	 * were busy */
	write_lock(&peer->conn_lock);
	list_for_each(_p, &peer->conn_active) {
		conn = list_entry(_p, struct rxrpc_connection, link);
		if (conn->addr.sin_port		== x_port	&&
		    conn->in_epoch		== x_epoch	&&
		    conn->conn_id		== x_connid	&&
		    conn->security_ix		== x_secix	&&
		    conn->service_id		== x_servid	&& 
		    conn->in_clientflag		== x_clflag)
			goto found_active_second_chance;
	}

	/* search the transport's graveyard list */
	spin_lock(&peer->conn_gylock);
	list_for_each(_p, &peer->conn_graveyard) {
		conn = list_entry(_p, struct rxrpc_connection, link);
		if (conn->addr.sin_port		== x_port	&&
		    conn->in_epoch		== x_epoch	&&
		    conn->conn_id		== x_connid	&&
		    conn->security_ix		== x_secix	&&
		    conn->service_id		== x_servid	&& 
		    conn->in_clientflag		== x_clflag)
			goto found_in_graveyard;
	}
	spin_unlock(&peer->conn_gylock);

	/* outbound connections aren't created here */
	if (!x_clflag) {
		write_unlock(&peer->conn_lock);
		_leave(" = -ENOENT");
		return -ENOENT;
	}

	/* we can now add the new candidate to the list */
	_debug("created connection: {%08x} [in]", ntohl(candidate->conn_id));
	rxrpc_get_peer(peer);
	conn = candidate;
	candidate = NULL;
	atomic_inc(&peer->conn_count);
	fresh = 1;

 make_active:
	list_add_tail(&conn->link, &peer->conn_active);

 success_uwfree:
	write_unlock(&peer->conn_lock);

	if (candidate) {
		write_lock(&peer->conn_idlock);
		list_del(&candidate->id_link);
		write_unlock(&peer->conn_idlock);

		__RXACCT(atomic_dec(&rxrpc_connection_count));
		kfree(candidate);
	}

	if (fresh) {
		down_write(&rxrpc_conns_sem);
		list_add_tail(&conn->proc_link, &rxrpc_conns);
		up_write(&rxrpc_conns_sem);
	}

 success:
	*_conn = conn;
	_leave(" = 0 (%p)", conn);
	return 0;

	/* handle the connection being found in the active list straight off */
 found_active:
	rxrpc_get_connection(conn);
	read_unlock(&peer->conn_lock);
	goto success;

	/* handle resurrecting a connection from the graveyard */
 found_in_graveyard:
	_debug("resurrecting connection: {%08x} [in]", ntohl(conn->conn_id));
	rxrpc_get_peer(peer);
	rxrpc_get_connection(conn);
	rxrpc_krxtimod_del_timer(&conn->timeout);
	list_del_init(&conn->link);
	spin_unlock(&peer->conn_gylock);
	goto make_active;

	/* handle finding the connection on the second time through the active
	 * list */
 found_active_second_chance:
	rxrpc_get_connection(conn);
	goto success_uwfree;

} /* end rxrpc_connection_lookup() */

/*****************************************************************************/
/*
 * finish using a connection record
 * - it will be transferred to the peer's connection graveyard when refcount
 *   reaches 0
 */
void rxrpc_put_connection(struct rxrpc_connection *conn)
{
	struct rxrpc_peer *peer;

	if (!conn)
		return;

	_enter("%p{u=%d p=%hu}",
	       conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port));

	peer = conn->peer;
	spin_lock(&peer->conn_gylock);

	/* sanity check */
	if (atomic_read(&conn->usage) <= 0)
		BUG();

	if (likely(!atomic_dec_and_test(&conn->usage))) {
		spin_unlock(&peer->conn_gylock);
		_leave("");
		return;
	}

	/* move to graveyard queue */
	_debug("burying connection: {%08x}", ntohl(conn->conn_id));
	list_del(&conn->link);
	list_add_tail(&conn->link, &peer->conn_graveyard);

	rxrpc_krxtimod_add_timer(&conn->timeout, rxrpc_conn_timeout * HZ);

	spin_unlock(&peer->conn_gylock);

	rxrpc_put_peer(conn->peer);

	_leave(" [killed]");
} /* end rxrpc_put_connection() */

/*****************************************************************************/
/*
 * free a connection record
 */
static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn)
{
	struct rxrpc_peer *peer;

	_enter("%p{u=%d p=%hu}",
	       conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port));

	peer = conn->peer;

	if (atomic_read(&conn->usage) < 0)
		BUG();

	/* remove from graveyard if still dead */
	spin_lock(&peer->conn_gylock);
	if (atomic_read(&conn->usage) == 0) {
		list_del_init(&conn->link);
	}
	else {
		conn = NULL;
	}
	spin_unlock(&peer->conn_gylock);

	if (!conn) {
		_leave("");
		return; /* resurrected */
	}

	_debug("--- Destroying Connection %p{%08x} ---",
	       conn, ntohl(conn->conn_id));

	down_write(&rxrpc_conns_sem);
	list_del(&conn->proc_link);
	up_write(&rxrpc_conns_sem);

	write_lock(&peer->conn_idlock);
	list_del(&conn->id_link);
	write_unlock(&peer->conn_idlock);

	__RXACCT(atomic_dec(&rxrpc_connection_count));
	kfree(conn);

	/* if the graveyard is now empty, wake up anyone waiting for that */
	if (atomic_dec_and_test(&peer->conn_count))
		wake_up(&peer->conn_gy_waitq);

	_leave(" [destroyed]");
} /* end rxrpc_conn_do_timeout() */

/*****************************************************************************/
/*
 * clear all connection records from a peer endpoint
 */
void rxrpc_conn_clearall(struct rxrpc_peer *peer)
{
	DECLARE_WAITQUEUE(myself, current);

	struct rxrpc_connection *conn;
	int err;

	_enter("%p", peer);

	/* there shouldn't be any active conns remaining */
	if (!list_empty(&peer->conn_active))
		BUG();

	/* manually timeout all conns in the graveyard */
	spin_lock(&peer->conn_gylock);
	while (!list_empty(&peer->conn_graveyard)) {
		conn = list_entry(peer->conn_graveyard.next,
				  struct rxrpc_connection, link);
		err = rxrpc_krxtimod_del_timer(&conn->timeout);
		spin_unlock(&peer->conn_gylock);

		if (err == 0)
			rxrpc_conn_do_timeout(conn);

		spin_lock(&peer->conn_gylock);
	}
	spin_unlock(&peer->conn_gylock);

	/* wait for the the conn graveyard to be completely cleared */
	set_current_state(TASK_UNINTERRUPTIBLE);
	add_wait_queue(&peer->conn_gy_waitq, &myself);

	while (atomic_read(&peer->conn_count) != 0) {
		schedule();
		set_current_state(TASK_UNINTERRUPTIBLE);
	}

	remove_wait_queue(&peer->conn_gy_waitq, &myself);
	set_current_state(TASK_RUNNING);

	_leave("");
} /* end rxrpc_conn_clearall() */

/*****************************************************************************/
/*
 * allocate and prepare a message for sending out through the transport
 * endpoint
 */
int rxrpc_conn_newmsg(struct rxrpc_connection *conn,
		      struct rxrpc_call *call,
		      uint8_t type,
		      int dcount,
		      struct kvec diov[],
		      gfp_t alloc_flags,
		      struct rxrpc_message **_msg)
{
	struct rxrpc_message *msg;
	int loop;

	_enter("%p{%d},%p,%u", conn, ntohs(conn->addr.sin_port), call, type);

	if (dcount > 3) {
		_leave(" = -EINVAL");
		return -EINVAL;
	}

	msg = kmalloc(sizeof(struct rxrpc_message), alloc_flags);
	if (!msg) {
		_leave(" = -ENOMEM");
		return -ENOMEM;
	}

	memset(msg, 0, sizeof(*msg));
	atomic_set(&msg->usage, 1);

	INIT_LIST_HEAD(&msg->link);

	msg->state = RXRPC_MSG_PREPARED;

	msg->hdr.epoch		= conn->out_epoch;
	msg->hdr.cid		= conn->conn_id | (call ? call->chan_ix : 0);
	msg->hdr.callNumber	= call ? call->call_id : 0;
	msg->hdr.type		= type;
	msg->hdr.flags		= conn->out_clientflag;
	msg->hdr.securityIndex	= conn->security_ix;
	msg->hdr.serviceId	= conn->service_id;

	/* generate sequence numbers for data packets */
	if (call) {
		switch (type) {
		case RXRPC_PACKET_TYPE_DATA:
			msg->seq = ++call->snd_seq_count;
			msg->hdr.seq = htonl(msg->seq);
			break;
		case RXRPC_PACKET_TYPE_ACK:
			/* ACK sequence numbers are complicated. The following
			 * may be wrong:
			 * - jumbo packet ACKs should have a seq number
			 * - normal ACKs should not
			 */
		default:
			break;
		}
	}

	msg->dcount = dcount + 1;
	msg->dsize = sizeof(msg->hdr);
	msg->data[0].iov_len = sizeof(msg->hdr);
	msg->data[0].iov_base = &msg->hdr;

	for (loop=0; loop < dcount; loop++) {
		msg->dsize += diov[loop].iov_len;
		msg->data[loop+1].iov_len  = diov[loop].iov_len;
		msg->data[loop+1].iov_base = diov[loop].iov_base;
	}

	__RXACCT(atomic_inc(&rxrpc_message_count));
	*_msg = msg;
	_leave(" = 0 (%p) #%d", msg, atomic_read(&rxrpc_message_count));
	return 0;
} /* end rxrpc_conn_newmsg() */

/*****************************************************************************/
/*
 * free a message
 */
void __rxrpc_put_message(struct rxrpc_message *msg)
{
	int loop;

	_enter("%p #%d", msg, atomic_read(&rxrpc_message_count));

	if (msg->pkt)
		kfree_skb(msg->pkt);
	rxrpc_put_connection(msg->conn);

	for (loop = 0; loop < 8; loop++)
		if (test_bit(loop, &msg->dfree))
			kfree(msg->data[loop].iov_base);

	__RXACCT(atomic_dec(&rxrpc_message_count));
	kfree(msg);

	_leave("");
} /* end __rxrpc_put_message() */

/*****************************************************************************/
/*
 * send a message out through the transport endpoint
 */
int rxrpc_conn_sendmsg(struct rxrpc_connection *conn,
		       struct rxrpc_message *msg)
{
	struct msghdr msghdr;
	int ret;

	_enter("%p{%d}", conn, ntohs(conn->addr.sin_port));

	/* fill in some fields in the header */
	spin_lock(&conn->lock);
	msg->hdr.serial = htonl(++conn->serial_counter);
	msg->rttdone = 0;
	spin_unlock(&conn->lock);

	/* set up the message to be transmitted */
	msghdr.msg_name		= &conn->addr;
	msghdr.msg_namelen	= sizeof(conn->addr);
	msghdr.msg_control	= NULL;
	msghdr.msg_controllen	= 0;
	msghdr.msg_flags	= MSG_CONFIRM | MSG_DONTWAIT;

	_net("Sending message type %d of %Zd bytes to %08x:%d",
	     msg->hdr.type,
	     msg->dsize,
	     ntohl(conn->addr.sin_addr.s_addr),
	     ntohs(conn->addr.sin_port));

	/* send the message */
	ret = kernel_sendmsg(conn->trans->socket, &msghdr,
			     msg->data, msg->dcount, msg->dsize);
	if (ret < 0) {
		msg->state = RXRPC_MSG_ERROR;
	} else {
		msg->state = RXRPC_MSG_SENT;
		ret = 0;

		spin_lock(&conn->lock);
		do_gettimeofday(&conn->atime);
		msg->stamp = conn->atime;
		spin_unlock(&conn->lock);
	}

	_leave(" = %d", ret);

	return ret;
} /* end rxrpc_conn_sendmsg() */

/*****************************************************************************/
/*
 * deal with a subsequent call packet
 */
int rxrpc_conn_receive_call_packet(struct rxrpc_connection *conn,
				   struct rxrpc_call *call,
				   struct rxrpc_message *msg)
{
	struct rxrpc_message *pmsg;
	struct list_head *_p;
	unsigned cix, seq;
	int ret = 0;

	_enter("%p,%p,%p", conn, call, msg);

	if (!call) {
		cix = ntohl(msg->hdr.cid) & RXRPC_CHANNELMASK;

		spin_lock(&conn->lock);
		call = conn->channels[cix];

		if (!call || call->call_id != msg->hdr.callNumber) {
			spin_unlock(&conn->lock);
			rxrpc_trans_immediate_abort(conn->trans, msg, -ENOENT);
			goto out;
		}
		else {
			rxrpc_get_call(call);
			spin_unlock(&conn->lock);
		}
	}
	else {
		rxrpc_get_call(call);
	}

	_proto("Received packet %%%u [%u] on call %hu:%u:%u",
	       ntohl(msg->hdr.serial),
	       ntohl(msg->hdr.seq),
	       ntohs(msg->hdr.serviceId),
	       ntohl(conn->conn_id),
	       ntohl(call->call_id));

	call->pkt_rcv_count++;

	if (msg->pkt->dst && msg->pkt->dst->dev)
		conn->peer->if_mtu =
			msg->pkt->dst->dev->mtu -
			msg->pkt->dst->dev->hard_header_len;

	/* queue on the call in seq order */
	rxrpc_get_message(msg);
	seq = msg->seq;

	spin_lock(&call->lock);
	list_for_each(_p, &call->rcv_receiveq) {
		pmsg = list_entry(_p, struct rxrpc_message, link);
		if (pmsg->seq > seq)
			break;
	}
	list_add_tail(&msg->link, _p);

	/* reset the activity timeout */
	call->flags |= RXRPC_CALL_RCV_PKT;
	mod_timer(&call->rcv_timeout,jiffies + rxrpc_call_rcv_timeout * HZ);

	spin_unlock(&call->lock);

	rxrpc_krxiod_queue_call(call);

	rxrpc_put_call(call);
 out:
	_leave(" = %d", ret);
	return ret;
} /* end rxrpc_conn_receive_call_packet() */

/*****************************************************************************/
/*
 * handle an ICMP error being applied to a connection
 */
void rxrpc_conn_handle_error(struct rxrpc_connection *conn,
			     int local, int errno)
{
	struct rxrpc_call *calls[4];
	int loop;

	_enter("%p{%d},%d", conn, ntohs(conn->addr.sin_port), errno);

	/* get a ref to all my calls in one go */
	memset(calls, 0, sizeof(calls));
	spin_lock(&conn->lock);

	for (loop = 3; loop >= 0; loop--) {
		if (conn->channels[loop]) {
			calls[loop] = conn->channels[loop];
			rxrpc_get_call(calls[loop]);
		}
	}

	spin_unlock(&conn->lock);

	/* now kick them all */
	for (loop = 3; loop >= 0; loop--) {
		if (calls[loop]) {
			rxrpc_call_handle_error(calls[loop], local, errno);
			rxrpc_put_call(calls[loop]);
		}
	}

	_leave("");
} /* end rxrpc_conn_handle_error() */