git.oblomov.eu Git - linux-2.6/blob - net/rxrpc/connection.c

   1 /* connection.c: Rx connection routines
   2  *
   3  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/sched.h>
  13 #include <linux/slab.h>
  14 #include <linux/module.h>
  15 #include <rxrpc/rxrpc.h>
  16 #include <rxrpc/transport.h>
  17 #include <rxrpc/peer.h>
  18 #include <rxrpc/connection.h>
  19 #include <rxrpc/call.h>
  20 #include <rxrpc/message.h>
  21 #include <linux/udp.h>
  22 #include <linux/ip.h>
  23 #include <net/sock.h>
  24 #include <asm/uaccess.h>
  25 #include "internal.h"
  26
  27 __RXACCT_DECL(atomic_t rxrpc_connection_count);
  28
  29 LIST_HEAD(rxrpc_conns);
  30 DECLARE_RWSEM(rxrpc_conns_sem);
  31 unsigned long rxrpc_conn_timeout = 60 * 60;
  32
  33 static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn);
  34
  35 static void __rxrpc_conn_timeout(rxrpc_timer_t *timer)
  36 {
  37         struct rxrpc_connection *conn =
  38                 list_entry(timer, struct rxrpc_connection, timeout);
  39
  40         _debug("Rx CONN TIMEOUT [%p{u=%d}]", conn, atomic_read(&conn->usage));
  41
  42         rxrpc_conn_do_timeout(conn);
  43 }
  44
  45 static const struct rxrpc_timer_ops rxrpc_conn_timer_ops = {
  46         .timed_out      = __rxrpc_conn_timeout,
  47 };
  48
  49 /*****************************************************************************/
  50 /*
  51  * create a new connection record
  52  */
  53 static inline int __rxrpc_create_connection(struct rxrpc_peer *peer,
  54                                             struct rxrpc_connection **_conn)
  55 {
  56         struct rxrpc_connection *conn;
  57
  58         _enter("%p",peer);
  59
  60         /* allocate and initialise a connection record */
  61         conn = kzalloc(sizeof(struct rxrpc_connection), GFP_KERNEL);
  62         if (!conn) {
  63                 _leave(" = -ENOMEM");
  64                 return -ENOMEM;
  65         }
  66
  67         atomic_set(&conn->usage, 1);
  68
  69         INIT_LIST_HEAD(&conn->link);
  70         INIT_LIST_HEAD(&conn->id_link);
  71         init_waitqueue_head(&conn->chanwait);
  72         spin_lock_init(&conn->lock);
  73         rxrpc_timer_init(&conn->timeout, &rxrpc_conn_timer_ops);
  74
  75         do_gettimeofday(&conn->atime);
  76         conn->mtu_size = 1024;
  77         conn->peer = peer;
  78         conn->trans = peer->trans;
  79
  80         __RXACCT(atomic_inc(&rxrpc_connection_count));
  81         *_conn = conn;
  82         _leave(" = 0 (%p)", conn);
  83
  84         return 0;
  85 } /* end __rxrpc_create_connection() */
  86
  87 /*****************************************************************************/
  88 /*
  89  * create a new connection record for outgoing connections
  90  */
  91 int rxrpc_create_connection(struct rxrpc_transport *trans,
  92                             __be16 port,
  93                             __be32 addr,
  94                             uint16_t service_id,
  95                             void *security,
  96                             struct rxrpc_connection **_conn)
  97 {
  98         struct rxrpc_connection *candidate, *conn;
  99         struct rxrpc_peer *peer;
 100         struct list_head *_p;
 101         __be32 connid;
 102         int ret;
 103
 104         _enter("%p{%hu},%u,%hu", trans, trans->port, ntohs(port), service_id);
 105
 106         /* get a peer record */
 107         ret = rxrpc_peer_lookup(trans, addr, &peer);
 108         if (ret < 0) {
 109                 _leave(" = %d", ret);
 110                 return ret;
 111         }
 112
 113         /* allocate and initialise a connection record */
 114         ret = __rxrpc_create_connection(peer, &candidate);
 115         if (ret < 0) {
 116                 rxrpc_put_peer(peer);
 117                 _leave(" = %d", ret);
 118                 return ret;
 119         }
 120
 121         /* fill in the specific bits */
 122         candidate->addr.sin_family      = AF_INET;
 123         candidate->addr.sin_port        = port;
 124         candidate->addr.sin_addr.s_addr = addr;
 125
 126         candidate->in_epoch             = rxrpc_epoch;
 127         candidate->out_epoch            = rxrpc_epoch;
 128         candidate->in_clientflag        = 0;
 129         candidate->out_clientflag       = RXRPC_CLIENT_INITIATED;
 130         candidate->service_id           = htons(service_id);
 131
 132         /* invent a unique connection ID */
 133         write_lock(&peer->conn_idlock);
 134
 135  try_next_id:
 136         connid = htonl(peer->conn_idcounter & RXRPC_CIDMASK);
 137         peer->conn_idcounter += RXRPC_MAXCALLS;
 138
 139         list_for_each(_p, &peer->conn_idlist) {
 140                 conn = list_entry(_p, struct rxrpc_connection, id_link);
 141                 if (connid == conn->conn_id)
 142                         goto try_next_id;
 143                 if (connid > conn->conn_id)
 144                         break;
 145         }
 146
 147         _debug("selected candidate conn ID %x.%u",
 148                ntohl(peer->addr.s_addr), ntohl(connid));
 149
 150         candidate->conn_id = connid;
 151         list_add_tail(&candidate->id_link, _p);
 152
 153         write_unlock(&peer->conn_idlock);
 154
 155         /* attach to peer */
 156         candidate->peer = peer;
 157
 158         write_lock(&peer->conn_lock);
 159
 160         /* search the peer's transport graveyard list */
 161         spin_lock(&peer->conn_gylock);
 162         list_for_each(_p, &peer->conn_graveyard) {
 163                 conn = list_entry(_p, struct rxrpc_connection, link);
 164                 if (conn->addr.sin_port == candidate->addr.sin_port     &&
 165                     conn->security_ix   == candidate->security_ix       &&
 166                     conn->service_id    == candidate->service_id        &&
 167                     conn->in_clientflag == 0)
 168                         goto found_in_graveyard;
 169         }
 170         spin_unlock(&peer->conn_gylock);
 171
 172         /* pick the new candidate */
 173         _debug("created connection: {%08x} [out]", ntohl(candidate->conn_id));
 174         atomic_inc(&peer->conn_count);
 175         conn = candidate;
 176         candidate = NULL;
 177
 178  make_active:
 179         list_add_tail(&conn->link, &peer->conn_active);
 180         write_unlock(&peer->conn_lock);
 181
 182         if (candidate) {
 183                 write_lock(&peer->conn_idlock);
 184                 list_del(&candidate->id_link);
 185                 write_unlock(&peer->conn_idlock);
 186
 187                 __RXACCT(atomic_dec(&rxrpc_connection_count));
 188                 kfree(candidate);
 189         }
 190         else {
 191                 down_write(&rxrpc_conns_sem);
 192                 list_add_tail(&conn->proc_link, &rxrpc_conns);
 193                 up_write(&rxrpc_conns_sem);
 194         }
 195
 196         *_conn = conn;
 197         _leave(" = 0 (%p)", conn);
 198
 199         return 0;
 200
 201         /* handle resurrecting a connection from the graveyard */
 202  found_in_graveyard:
 203         _debug("resurrecting connection: {%08x} [out]", ntohl(conn->conn_id));
 204         rxrpc_get_connection(conn);
 205         rxrpc_krxtimod_del_timer(&conn->timeout);
 206         list_del_init(&conn->link);
 207         spin_unlock(&peer->conn_gylock);
 208         goto make_active;
 209 } /* end rxrpc_create_connection() */
 210
 211 /*****************************************************************************/
 212 /*
 213  * lookup the connection for an incoming packet
 214  * - create a new connection record for unrecorded incoming connections
 215  */
 216 int rxrpc_connection_lookup(struct rxrpc_peer *peer,
 217                             struct rxrpc_message *msg,
 218                             struct rxrpc_connection **_conn)
 219 {
 220         struct rxrpc_connection *conn, *candidate = NULL;
 221         struct list_head *_p;
 222         struct sk_buff *pkt = msg->pkt;
 223         int ret, fresh = 0;
 224         __be32 x_epoch, x_connid;
 225         __be16 x_port, x_servid;
 226         __u32 x_secix;
 227         u8 x_clflag;
 228
 229         _enter("%p{{%hu}},%u,%hu",
 230                peer,
 231                peer->trans->port,
 232                ntohs(pkt->h.uh->source),
 233                ntohs(msg->hdr.serviceId));
 234
 235         x_port          = pkt->h.uh->source;
 236         x_epoch         = msg->hdr.epoch;
 237         x_clflag        = msg->hdr.flags & RXRPC_CLIENT_INITIATED;
 238         x_connid        = htonl(ntohl(msg->hdr.cid) & RXRPC_CIDMASK);
 239         x_servid        = msg->hdr.serviceId;
 240         x_secix         = msg->hdr.securityIndex;
 241
 242         /* [common case] search the transport's active list first */
 243         read_lock(&peer->conn_lock);
 244         list_for_each(_p, &peer->conn_active) {
 245                 conn = list_entry(_p, struct rxrpc_connection, link);
 246                 if (conn->addr.sin_port         == x_port       &&
 247                     conn->in_epoch              == x_epoch      &&
 248                     conn->conn_id               == x_connid     &&
 249                     conn->security_ix           == x_secix      &&
 250                     conn->service_id            == x_servid     &&
 251                     conn->in_clientflag         == x_clflag)
 252                         goto found_active;
 253         }
 254         read_unlock(&peer->conn_lock);
 255
 256         /* [uncommon case] not active
 257          * - create a candidate for a new record if an inbound connection
 258          * - only examine the graveyard for an outbound connection
 259          */
 260         if (x_clflag) {
 261                 ret = __rxrpc_create_connection(peer, &candidate);
 262                 if (ret < 0) {
 263                         _leave(" = %d", ret);
 264                         return ret;
 265                 }
 266
 267                 /* fill in the specifics */
 268                 candidate->addr.sin_family      = AF_INET;
 269                 candidate->addr.sin_port        = x_port;
 270                 candidate->addr.sin_addr.s_addr = pkt->nh.iph->saddr;
 271                 candidate->in_epoch             = x_epoch;
 272                 candidate->out_epoch            = x_epoch;
 273                 candidate->in_clientflag        = RXRPC_CLIENT_INITIATED;
 274                 candidate->out_clientflag       = 0;
 275                 candidate->conn_id              = x_connid;
 276                 candidate->service_id           = x_servid;
 277                 candidate->security_ix          = x_secix;
 278         }
 279
 280         /* search the active list again, just in case it appeared whilst we
 281          * were busy */
 282         write_lock(&peer->conn_lock);
 283         list_for_each(_p, &peer->conn_active) {
 284                 conn = list_entry(_p, struct rxrpc_connection, link);
 285                 if (conn->addr.sin_port         == x_port       &&
 286                     conn->in_epoch              == x_epoch      &&
 287                     conn->conn_id               == x_connid     &&
 288                     conn->security_ix           == x_secix      &&
 289                     conn->service_id            == x_servid     &&
 290                     conn->in_clientflag         == x_clflag)
 291                         goto found_active_second_chance;
 292         }
 293
 294         /* search the transport's graveyard list */
 295         spin_lock(&peer->conn_gylock);
 296         list_for_each(_p, &peer->conn_graveyard) {
 297                 conn = list_entry(_p, struct rxrpc_connection, link);
 298                 if (conn->addr.sin_port         == x_port       &&
 299                     conn->in_epoch              == x_epoch      &&
 300                     conn->conn_id               == x_connid     &&
 301                     conn->security_ix           == x_secix      &&
 302                     conn->service_id            == x_servid     &&
 303                     conn->in_clientflag         == x_clflag)
 304                         goto found_in_graveyard;
 305         }
 306         spin_unlock(&peer->conn_gylock);
 307
 308         /* outbound connections aren't created here */
 309         if (!x_clflag) {
 310                 write_unlock(&peer->conn_lock);
 311                 _leave(" = -ENOENT");
 312                 return -ENOENT;
 313         }
 314
 315         /* we can now add the new candidate to the list */
 316         _debug("created connection: {%08x} [in]", ntohl(candidate->conn_id));
 317         rxrpc_get_peer(peer);
 318         conn = candidate;
 319         candidate = NULL;
 320         atomic_inc(&peer->conn_count);
 321         fresh = 1;
 322
 323  make_active:
 324         list_add_tail(&conn->link, &peer->conn_active);
 325
 326  success_uwfree:
 327         write_unlock(&peer->conn_lock);
 328
 329         if (candidate) {
 330                 write_lock(&peer->conn_idlock);
 331                 list_del(&candidate->id_link);
 332                 write_unlock(&peer->conn_idlock);
 333
 334                 __RXACCT(atomic_dec(&rxrpc_connection_count));
 335                 kfree(candidate);
 336         }
 337
 338         if (fresh) {
 339                 down_write(&rxrpc_conns_sem);
 340                 list_add_tail(&conn->proc_link, &rxrpc_conns);
 341                 up_write(&rxrpc_conns_sem);
 342         }
 343
 344  success:
 345         *_conn = conn;
 346         _leave(" = 0 (%p)", conn);
 347         return 0;
 348
 349         /* handle the connection being found in the active list straight off */
 350  found_active:
 351         rxrpc_get_connection(conn);
 352         read_unlock(&peer->conn_lock);
 353         goto success;
 354
 355         /* handle resurrecting a connection from the graveyard */
 356  found_in_graveyard:
 357         _debug("resurrecting connection: {%08x} [in]", ntohl(conn->conn_id));
 358         rxrpc_get_peer(peer);
 359         rxrpc_get_connection(conn);
 360         rxrpc_krxtimod_del_timer(&conn->timeout);
 361         list_del_init(&conn->link);
 362         spin_unlock(&peer->conn_gylock);
 363         goto make_active;
 364
 365         /* handle finding the connection on the second time through the active
 366          * list */
 367  found_active_second_chance:
 368         rxrpc_get_connection(conn);
 369         goto success_uwfree;
 370
 371 } /* end rxrpc_connection_lookup() */
 372
 373 /*****************************************************************************/
 374 /*
 375  * finish using a connection record
 376  * - it will be transferred to the peer's connection graveyard when refcount
 377  *   reaches 0
 378  */
 379 void rxrpc_put_connection(struct rxrpc_connection *conn)
 380 {
 381         struct rxrpc_peer *peer;
 382
 383         if (!conn)
 384                 return;
 385
 386         _enter("%p{u=%d p=%hu}",
 387                conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port));
 388
 389         peer = conn->peer;
 390         spin_lock(&peer->conn_gylock);
 391
 392         /* sanity check */
 393         if (atomic_read(&conn->usage) <= 0)
 394                 BUG();
 395
 396         if (likely(!atomic_dec_and_test(&conn->usage))) {
 397                 spin_unlock(&peer->conn_gylock);
 398                 _leave("");
 399                 return;
 400         }
 401
 402         /* move to graveyard queue */
 403         _debug("burying connection: {%08x}", ntohl(conn->conn_id));
 404         list_move_tail(&conn->link, &peer->conn_graveyard);
 405
 406         rxrpc_krxtimod_add_timer(&conn->timeout, rxrpc_conn_timeout * HZ);
 407
 408         spin_unlock(&peer->conn_gylock);
 409
 410         rxrpc_put_peer(conn->peer);
 411
 412         _leave(" [killed]");
 413 } /* end rxrpc_put_connection() */
 414
 415 /*****************************************************************************/
 416 /*
 417  * free a connection record
 418  */
 419 static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn)
 420 {
 421         struct rxrpc_peer *peer;
 422
 423         _enter("%p{u=%d p=%hu}",
 424                conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port));
 425
 426         peer = conn->peer;
 427
 428         if (atomic_read(&conn->usage) < 0)
 429                 BUG();
 430
 431         /* remove from graveyard if still dead */
 432         spin_lock(&peer->conn_gylock);
 433         if (atomic_read(&conn->usage) == 0) {
 434                 list_del_init(&conn->link);
 435         }
 436         else {
 437                 conn = NULL;
 438         }
 439         spin_unlock(&peer->conn_gylock);
 440
 441         if (!conn) {
 442                 _leave("");
 443                 return; /* resurrected */
 444         }
 445
 446         _debug("--- Destroying Connection %p{%08x} ---",
 447                conn, ntohl(conn->conn_id));
 448
 449         down_write(&rxrpc_conns_sem);
 450         list_del(&conn->proc_link);
 451         up_write(&rxrpc_conns_sem);
 452
 453         write_lock(&peer->conn_idlock);
 454         list_del(&conn->id_link);
 455         write_unlock(&peer->conn_idlock);
 456
 457         __RXACCT(atomic_dec(&rxrpc_connection_count));
 458         kfree(conn);
 459
 460         /* if the graveyard is now empty, wake up anyone waiting for that */
 461         if (atomic_dec_and_test(&peer->conn_count))
 462                 wake_up(&peer->conn_gy_waitq);
 463
 464         _leave(" [destroyed]");
 465 } /* end rxrpc_conn_do_timeout() */
 466
 467 /*****************************************************************************/
 468 /*
 469  * clear all connection records from a peer endpoint
 470  */
 471 void rxrpc_conn_clearall(struct rxrpc_peer *peer)
 472 {
 473         DECLARE_WAITQUEUE(myself, current);
 474
 475         struct rxrpc_connection *conn;
 476         int err;
 477
 478         _enter("%p", peer);
 479
 480         /* there shouldn't be any active conns remaining */
 481         if (!list_empty(&peer->conn_active))
 482                 BUG();
 483
 484         /* manually timeout all conns in the graveyard */
 485         spin_lock(&peer->conn_gylock);
 486         while (!list_empty(&peer->conn_graveyard)) {
 487                 conn = list_entry(peer->conn_graveyard.next,
 488                                   struct rxrpc_connection, link);
 489                 err = rxrpc_krxtimod_del_timer(&conn->timeout);
 490                 spin_unlock(&peer->conn_gylock);
 491
 492                 if (err == 0)
 493                         rxrpc_conn_do_timeout(conn);
 494
 495                 spin_lock(&peer->conn_gylock);
 496         }
 497         spin_unlock(&peer->conn_gylock);
 498
 499         /* wait for the the conn graveyard to be completely cleared */
 500         set_current_state(TASK_UNINTERRUPTIBLE);
 501         add_wait_queue(&peer->conn_gy_waitq, &myself);
 502
 503         while (atomic_read(&peer->conn_count) != 0) {
 504                 schedule();
 505                 set_current_state(TASK_UNINTERRUPTIBLE);
 506         }
 507
 508         remove_wait_queue(&peer->conn_gy_waitq, &myself);
 509         set_current_state(TASK_RUNNING);
 510
 511         _leave("");
 512 } /* end rxrpc_conn_clearall() */
 513
 514 /*****************************************************************************/
 515 /*
 516  * allocate and prepare a message for sending out through the transport
 517  * endpoint
 518  */
 519 int rxrpc_conn_newmsg(struct rxrpc_connection *conn,
 520                       struct rxrpc_call *call,
 521                       uint8_t type,
 522                       int dcount,
 523                       struct kvec diov[],
 524                       gfp_t alloc_flags,
 525                       struct rxrpc_message **_msg)
 526 {
 527         struct rxrpc_message *msg;
 528         int loop;
 529
 530         _enter("%p{%d},%p,%u", conn, ntohs(conn->addr.sin_port), call, type);
 531
 532         if (dcount > 3) {
 533                 _leave(" = -EINVAL");
 534                 return -EINVAL;
 535         }
 536
 537         msg = kzalloc(sizeof(struct rxrpc_message), alloc_flags);
 538         if (!msg) {
 539                 _leave(" = -ENOMEM");
 540                 return -ENOMEM;
 541         }
 542
 543         atomic_set(&msg->usage, 1);
 544
 545         INIT_LIST_HEAD(&msg->link);
 546
 547         msg->state = RXRPC_MSG_PREPARED;
 548
 549         msg->hdr.epoch          = conn->out_epoch;
 550         msg->hdr.cid            = conn->conn_id | (call ? call->chan_ix : 0);
 551         msg->hdr.callNumber     = call ? call->call_id : 0;
 552         msg->hdr.type           = type;
 553         msg->hdr.flags          = conn->out_clientflag;
 554         msg->hdr.securityIndex  = conn->security_ix;
 555         msg->hdr.serviceId      = conn->service_id;
 556
 557         /* generate sequence numbers for data packets */
 558         if (call) {
 559                 switch (type) {
 560                 case RXRPC_PACKET_TYPE_DATA:
 561                         msg->seq = ++call->snd_seq_count;
 562                         msg->hdr.seq = htonl(msg->seq);
 563                         break;
 564                 case RXRPC_PACKET_TYPE_ACK:
 565                         /* ACK sequence numbers are complicated. The following
 566                          * may be wrong:
 567                          * - jumbo packet ACKs should have a seq number
 568                          * - normal ACKs should not
 569                          */
 570                 default:
 571                         break;
 572                 }
 573         }
 574
 575         msg->dcount = dcount + 1;
 576         msg->dsize = sizeof(msg->hdr);
 577         msg->data[0].iov_len = sizeof(msg->hdr);
 578         msg->data[0].iov_base = &msg->hdr;
 579
 580         for (loop=0; loop < dcount; loop++) {
 581                 msg->dsize += diov[loop].iov_len;
 582                 msg->data[loop+1].iov_len  = diov[loop].iov_len;
 583                 msg->data[loop+1].iov_base = diov[loop].iov_base;
 584         }
 585
 586         __RXACCT(atomic_inc(&rxrpc_message_count));
 587         *_msg = msg;
 588         _leave(" = 0 (%p) #%d", msg, atomic_read(&rxrpc_message_count));
 589         return 0;
 590 } /* end rxrpc_conn_newmsg() */
 591
 592 /*****************************************************************************/
 593 /*
 594  * free a message
 595  */
 596 void __rxrpc_put_message(struct rxrpc_message *msg)
 597 {
 598         int loop;
 599
 600         _enter("%p #%d", msg, atomic_read(&rxrpc_message_count));
 601
 602         if (msg->pkt)
 603                 kfree_skb(msg->pkt);
 604         rxrpc_put_connection(msg->conn);
 605
 606         for (loop = 0; loop < 8; loop++)
 607                 if (test_bit(loop, &msg->dfree))
 608                         kfree(msg->data[loop].iov_base);
 609
 610         __RXACCT(atomic_dec(&rxrpc_message_count));
 611         kfree(msg);
 612
 613         _leave("");
 614 } /* end __rxrpc_put_message() */
 615
 616 /*****************************************************************************/
 617 /*
 618  * send a message out through the transport endpoint
 619  */
 620 int rxrpc_conn_sendmsg(struct rxrpc_connection *conn,
 621                        struct rxrpc_message *msg)
 622 {
 623         struct msghdr msghdr;
 624         int ret;
 625
 626         _enter("%p{%d}", conn, ntohs(conn->addr.sin_port));
 627
 628         /* fill in some fields in the header */
 629         spin_lock(&conn->lock);
 630         msg->hdr.serial = htonl(++conn->serial_counter);
 631         msg->rttdone = 0;
 632         spin_unlock(&conn->lock);
 633
 634         /* set up the message to be transmitted */
 635         msghdr.msg_name         = &conn->addr;
 636         msghdr.msg_namelen      = sizeof(conn->addr);
 637         msghdr.msg_control      = NULL;
 638         msghdr.msg_controllen   = 0;
 639         msghdr.msg_flags        = MSG_CONFIRM | MSG_DONTWAIT;
 640
 641         _net("Sending message type %d of %Zd bytes to %08x:%d",
 642              msg->hdr.type,
 643              msg->dsize,
 644              ntohl(conn->addr.sin_addr.s_addr),
 645              ntohs(conn->addr.sin_port));
 646
 647         /* send the message */
 648         ret = kernel_sendmsg(conn->trans->socket, &msghdr,
 649                              msg->data, msg->dcount, msg->dsize);
 650         if (ret < 0) {
 651                 msg->state = RXRPC_MSG_ERROR;
 652         } else {
 653                 msg->state = RXRPC_MSG_SENT;
 654                 ret = 0;
 655
 656                 spin_lock(&conn->lock);
 657                 do_gettimeofday(&conn->atime);
 658                 msg->stamp = conn->atime;
 659                 spin_unlock(&conn->lock);
 660         }
 661
 662         _leave(" = %d", ret);
 663
 664         return ret;
 665 } /* end rxrpc_conn_sendmsg() */
 666
 667 /*****************************************************************************/
 668 /*
 669  * deal with a subsequent call packet
 670  */
 671 int rxrpc_conn_receive_call_packet(struct rxrpc_connection *conn,
 672                                    struct rxrpc_call *call,
 673                                    struct rxrpc_message *msg)
 674 {
 675         struct rxrpc_message *pmsg;
 676         struct dst_entry *dst;
 677         struct list_head *_p;
 678         unsigned cix, seq;
 679         int ret = 0;
 680
 681         _enter("%p,%p,%p", conn, call, msg);
 682
 683         if (!call) {
 684                 cix = ntohl(msg->hdr.cid) & RXRPC_CHANNELMASK;
 685
 686                 spin_lock(&conn->lock);
 687                 call = conn->channels[cix];
 688
 689                 if (!call || call->call_id != msg->hdr.callNumber) {
 690                         spin_unlock(&conn->lock);
 691                         rxrpc_trans_immediate_abort(conn->trans, msg, -ENOENT);
 692                         goto out;
 693                 }
 694                 else {
 695                         rxrpc_get_call(call);
 696                         spin_unlock(&conn->lock);
 697                 }
 698         }
 699         else {
 700                 rxrpc_get_call(call);
 701         }
 702
 703         _proto("Received packet %%%u [%u] on call %hu:%u:%u",
 704                ntohl(msg->hdr.serial),
 705                ntohl(msg->hdr.seq),
 706                ntohs(msg->hdr.serviceId),
 707                ntohl(conn->conn_id),
 708                ntohl(call->call_id));
 709
 710         call->pkt_rcv_count++;
 711
 712         dst = msg->pkt->dst;
 713         if (dst && dst->dev)
 714                 conn->peer->if_mtu =
 715                         dst->dev->mtu - dst->dev->hard_header_len;
 716
 717         /* queue on the call in seq order */
 718         rxrpc_get_message(msg);
 719         seq = msg->seq;
 720
 721         spin_lock(&call->lock);
 722         list_for_each(_p, &call->rcv_receiveq) {
 723                 pmsg = list_entry(_p, struct rxrpc_message, link);
 724                 if (pmsg->seq > seq)
 725                         break;
 726         }
 727         list_add_tail(&msg->link, _p);
 728
 729         /* reset the activity timeout */
 730         call->flags |= RXRPC_CALL_RCV_PKT;
 731         mod_timer(&call->rcv_timeout,jiffies + rxrpc_call_rcv_timeout * HZ);
 732
 733         spin_unlock(&call->lock);
 734
 735         rxrpc_krxiod_queue_call(call);
 736
 737         rxrpc_put_call(call);
 738  out:
 739         _leave(" = %d", ret);
 740         return ret;
 741 } /* end rxrpc_conn_receive_call_packet() */
 742
 743 /*****************************************************************************/
 744 /*
 745  * handle an ICMP error being applied to a connection
 746  */
 747 void rxrpc_conn_handle_error(struct rxrpc_connection *conn,
 748                              int local, int errno)
 749 {
 750         struct rxrpc_call *calls[4];
 751         int loop;
 752
 753         _enter("%p{%d},%d", conn, ntohs(conn->addr.sin_port), errno);
 754
 755         /* get a ref to all my calls in one go */
 756         memset(calls, 0, sizeof(calls));
 757         spin_lock(&conn->lock);
 758
 759         for (loop = 3; loop >= 0; loop--) {
 760                 if (conn->channels[loop]) {
 761                         calls[loop] = conn->channels[loop];
 762                         rxrpc_get_call(calls[loop]);
 763                 }
 764         }
 765
 766         spin_unlock(&conn->lock);
 767
 768         /* now kick them all */
 769         for (loop = 3; loop >= 0; loop--) {
 770                 if (calls[loop]) {
 771                         rxrpc_call_handle_error(calls[loop], local, errno);
 772                         rxrpc_put_call(calls[loop]);
 773                 }
 774         }
 775
 776         _leave("");
 777 } /* end rxrpc_conn_handle_error() */