net/tipc/port.c

   1 /*
   2  * net/tipc/port.c: TIPC port code
   3  *
   4  * Copyright (c) 1992-2007, 2014, Ericsson AB
   5  * Copyright (c) 2004-2008, 2010-2013, Wind River Systems
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  *
  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.
  19  *
  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
  34  * POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 #include "core.h"
  38 #include "config.h"
  39 #include "port.h"
  40 #include "name_table.h"
  41 #include "socket.h"
  42
  43 /* Connection management: */
  44 #define PROBING_INTERVAL 3600000        /* [ms] => 1 h */
  45
  46 #define MAX_REJECT_SIZE 1024
  47
  48 DEFINE_SPINLOCK(tipc_port_list_lock);
  49
  50 static LIST_HEAD(ports);
  51 static void port_handle_node_down(unsigned long ref);
  52 static struct sk_buff *port_build_self_abort_msg(struct tipc_port *, u32 err);
  53 static struct sk_buff *port_build_peer_abort_msg(struct tipc_port *, u32 err);
  54 static void port_timeout(unsigned long ref);
  55
  56 /**
  57  * tipc_port_peer_msg - verify message was sent by connected port's peer
  58  *
  59  * Handles cases where the node's network address has changed from
  60  * the default of <0.0.0> to its configured setting.
  61  */
  62 int tipc_port_peer_msg(struct tipc_port *p_ptr, struct tipc_msg *msg)
  63 {
  64         u32 peernode;
  65         u32 orignode;
  66
  67         if (msg_origport(msg) != tipc_port_peerport(p_ptr))
  68                 return 0;
  69
  70         orignode = msg_orignode(msg);
  71         peernode = tipc_port_peernode(p_ptr);
  72         return (orignode == peernode) ||
  73                 (!orignode && (peernode == tipc_own_addr)) ||
  74                 (!peernode && (orignode == tipc_own_addr));
  75 }
  76
  77 /**
  78  * tipc_port_mcast_xmit - send a multicast message to local and remote
  79  * destinations
  80  */
  81 int tipc_port_mcast_xmit(struct tipc_port *oport,
  82                          struct tipc_name_seq const *seq,
  83                          struct iovec const *msg_sect,
  84                          unsigned int len)
  85 {
  86         struct tipc_msg *hdr;
  87         struct sk_buff *buf;
  88         struct sk_buff *ibuf = NULL;
  89         struct tipc_port_list dports = {0, NULL, };
  90         int ext_targets;
  91         int res;
  92
  93         /* Create multicast message */
  94         hdr = &oport->phdr;
  95         msg_set_type(hdr, TIPC_MCAST_MSG);
  96         msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE);
  97         msg_set_destport(hdr, 0);
  98         msg_set_destnode(hdr, 0);
  99         msg_set_nametype(hdr, seq->type);
 100         msg_set_namelower(hdr, seq->lower);
 101         msg_set_nameupper(hdr, seq->upper);
 102         msg_set_hdr_sz(hdr, MCAST_H_SIZE);
 103         res = tipc_msg_build(hdr, msg_sect, len, MAX_MSG_SIZE, &buf);
 104         if (unlikely(!buf))
 105                 return res;
 106
 107         /* Figure out where to send multicast message */
 108         ext_targets = tipc_nametbl_mc_translate(seq->type, seq->lower, seq->upper,
 109                                                 TIPC_NODE_SCOPE, &dports);
 110
 111         /* Send message to destinations (duplicate it only if necessary) */
 112         if (ext_targets) {
 113                 if (dports.count != 0) {
 114                         ibuf = skb_copy(buf, GFP_ATOMIC);
 115                         if (ibuf == NULL) {
 116                                 tipc_port_list_free(&dports);
 117                                 kfree_skb(buf);
 118                                 return -ENOMEM;
 119                         }
 120                 }
 121                 res = tipc_bclink_xmit(buf);
 122                 if ((res < 0) && (dports.count != 0))
 123                         kfree_skb(ibuf);
 124         } else {
 125                 ibuf = buf;
 126         }
 127
 128         if (res >= 0) {
 129                 if (ibuf)
 130                         tipc_port_mcast_rcv(ibuf, &dports);
 131         } else {
 132                 tipc_port_list_free(&dports);
 133         }
 134         return res;
 135 }
 136
 137 /**
 138  * tipc_port_mcast_rcv - deliver multicast message to all destination ports
 139  *
 140  * If there is no port list, perform a lookup to create one
 141  */
 142 void tipc_port_mcast_rcv(struct sk_buff *buf, struct tipc_port_list *dp)
 143 {
 144         struct tipc_msg *msg;
 145         struct tipc_port_list dports = {0, NULL, };
 146         struct tipc_port_list *item = dp;
 147         int cnt = 0;
 148
 149         msg = buf_msg(buf);
 150
 151         /* Create destination port list, if one wasn't supplied */
 152         if (dp == NULL) {
 153                 tipc_nametbl_mc_translate(msg_nametype(msg),
 154                                      msg_namelower(msg),
 155                                      msg_nameupper(msg),
 156                                      TIPC_CLUSTER_SCOPE,
 157                                      &dports);
 158                 item = dp = &dports;
 159         }
 160
 161         /* Deliver a copy of message to each destination port */
 162         if (dp->count != 0) {
 163                 msg_set_destnode(msg, tipc_own_addr);
 164                 if (dp->count == 1) {
 165                         msg_set_destport(msg, dp->ports[0]);
 166                         tipc_sk_rcv(buf);
 167                         tipc_port_list_free(dp);
 168                         return;
 169                 }
 170                 for (; cnt < dp->count; cnt++) {
 171                         int index = cnt % PLSIZE;
 172                         struct sk_buff *b = skb_clone(buf, GFP_ATOMIC);
 173
 174                         if (b == NULL) {
 175                                 pr_warn("Unable to deliver multicast message(s)\n");
 176                                 goto exit;
 177                         }
 178                         if ((index == 0) && (cnt != 0))
 179                                 item = item->next;
 180                         msg_set_destport(buf_msg(b), item->ports[index]);
 181                         tipc_sk_rcv(b);
 182                 }
 183         }
 184 exit:
 185         kfree_skb(buf);
 186         tipc_port_list_free(dp);
 187 }
 188
 189
 190 void tipc_port_wakeup(struct tipc_port *port)
 191 {
 192         tipc_sock_wakeup(tipc_port_to_sock(port));
 193 }
 194
 195 /* tipc_port_init - intiate TIPC port and lock it
 196  *
 197  * Returns obtained reference if initialization is successful, zero otherwise
 198  */
 199 u32 tipc_port_init(struct tipc_port *p_ptr,
 200                    const unsigned int importance)
 201 {
 202         struct tipc_msg *msg;
 203         u32 ref;
 204
 205         ref = tipc_ref_acquire(p_ptr, &p_ptr->lock);
 206         if (!ref) {
 207                 pr_warn("Port registration failed, ref. table exhausted\n");
 208                 return 0;
 209         }
 210
 211         p_ptr->max_pkt = MAX_PKT_DEFAULT;
 212         p_ptr->sent = 1;
 213         p_ptr->ref = ref;
 214         INIT_LIST_HEAD(&p_ptr->wait_list);
 215         INIT_LIST_HEAD(&p_ptr->subscription.nodesub_list);
 216         k_init_timer(&p_ptr->timer, (Handler)port_timeout, ref);
 217         INIT_LIST_HEAD(&p_ptr->publications);
 218         INIT_LIST_HEAD(&p_ptr->port_list);
 219
 220         /*
 221          * Must hold port list lock while initializing message header template
 222          * to ensure a change to node's own network address doesn't result
 223          * in template containing out-dated network address information
 224          */
 225         spin_lock_bh(&tipc_port_list_lock);
 226         msg = &p_ptr->phdr;
 227         tipc_msg_init(msg, importance, TIPC_NAMED_MSG, NAMED_H_SIZE, 0);
 228         msg_set_origport(msg, ref);
 229         list_add_tail(&p_ptr->port_list, &ports);
 230         spin_unlock_bh(&tipc_port_list_lock);
 231         return ref;
 232 }
 233
 234 void tipc_port_destroy(struct tipc_port *p_ptr)
 235 {
 236         struct sk_buff *buf = NULL;
 237         struct tipc_msg *msg = NULL;
 238         u32 peer;
 239
 240         tipc_withdraw(p_ptr, 0, NULL);
 241
 242         spin_lock_bh(p_ptr->lock);
 243         tipc_ref_discard(p_ptr->ref);
 244         spin_unlock_bh(p_ptr->lock);
 245
 246         k_cancel_timer(&p_ptr->timer);
 247         if (p_ptr->connected) {
 248                 buf = port_build_peer_abort_msg(p_ptr, TIPC_ERR_NO_PORT);
 249                 tipc_nodesub_unsubscribe(&p_ptr->subscription);
 250                 msg = buf_msg(buf);
 251                 peer = msg_destnode(msg);
 252                 tipc_link_xmit2(buf, peer, msg_link_selector(msg));
 253         }
 254         spin_lock_bh(&tipc_port_list_lock);
 255         list_del(&p_ptr->port_list);
 256         list_del(&p_ptr->wait_list);
 257         spin_unlock_bh(&tipc_port_list_lock);
 258         k_term_timer(&p_ptr->timer);
 259 }
 260
 261 /*
 262  * port_build_proto_msg(): create connection protocol message for port
 263  *
 264  * On entry the port must be locked and connected.
 265  */
 266 static struct sk_buff *port_build_proto_msg(struct tipc_port *p_ptr,
 267                                             u32 type, u32 ack)
 268 {
 269         struct sk_buff *buf;
 270         struct tipc_msg *msg;
 271
 272         buf = tipc_buf_acquire(INT_H_SIZE);
 273         if (buf) {
 274                 msg = buf_msg(buf);
 275                 tipc_msg_init(msg, CONN_MANAGER, type, INT_H_SIZE,
 276                               tipc_port_peernode(p_ptr));
 277                 msg_set_destport(msg, tipc_port_peerport(p_ptr));
 278                 msg_set_origport(msg, p_ptr->ref);
 279                 msg_set_msgcnt(msg, ack);
 280                 buf->next = NULL;
 281         }
 282         return buf;
 283 }
 284
 285 static void port_timeout(unsigned long ref)
 286 {
 287         struct tipc_port *p_ptr = tipc_port_lock(ref);
 288         struct sk_buff *buf = NULL;
 289         struct tipc_msg *msg = NULL;
 290
 291         if (!p_ptr)
 292                 return;
 293
 294         if (!p_ptr->connected) {
 295                 tipc_port_unlock(p_ptr);
 296                 return;
 297         }
 298
 299         /* Last probe answered ? */
 300         if (p_ptr->probing_state == TIPC_CONN_PROBING) {
 301                 buf = port_build_self_abort_msg(p_ptr, TIPC_ERR_NO_PORT);
 302         } else {
 303                 buf = port_build_proto_msg(p_ptr, CONN_PROBE, 0);
 304                 p_ptr->probing_state = TIPC_CONN_PROBING;
 305                 k_start_timer(&p_ptr->timer, p_ptr->probing_interval);
 306         }
 307         tipc_port_unlock(p_ptr);
 308         msg = buf_msg(buf);
 309         tipc_link_xmit2(buf, msg_destnode(msg), msg_link_selector(msg));
 310 }
 311
 312
 313 static void port_handle_node_down(unsigned long ref)
 314 {
 315         struct tipc_port *p_ptr = tipc_port_lock(ref);
 316         struct sk_buff *buf = NULL;
 317         struct tipc_msg *msg = NULL;
 318
 319         if (!p_ptr)
 320                 return;
 321         buf = port_build_self_abort_msg(p_ptr, TIPC_ERR_NO_NODE);
 322         tipc_port_unlock(p_ptr);
 323         msg = buf_msg(buf);
 324         tipc_link_xmit2(buf, msg_destnode(msg), msg_link_selector(msg));
 325 }
 326
 327
 328 static struct sk_buff *port_build_self_abort_msg(struct tipc_port *p_ptr, u32 err)
 329 {
 330         struct sk_buff *buf = port_build_peer_abort_msg(p_ptr, err);
 331
 332         if (buf) {
 333                 struct tipc_msg *msg = buf_msg(buf);
 334                 msg_swap_words(msg, 4, 5);
 335                 msg_swap_words(msg, 6, 7);
 336                 buf->next = NULL;
 337         }
 338         return buf;
 339 }
 340
 341
 342 static struct sk_buff *port_build_peer_abort_msg(struct tipc_port *p_ptr, u32 err)
 343 {
 344         struct sk_buff *buf;
 345         struct tipc_msg *msg;
 346         u32 imp;
 347
 348         if (!p_ptr->connected)
 349                 return NULL;
 350
 351         buf = tipc_buf_acquire(BASIC_H_SIZE);
 352         if (buf) {
 353                 msg = buf_msg(buf);
 354                 memcpy(msg, &p_ptr->phdr, BASIC_H_SIZE);
 355                 msg_set_hdr_sz(msg, BASIC_H_SIZE);
 356                 msg_set_size(msg, BASIC_H_SIZE);
 357                 imp = msg_importance(msg);
 358                 if (imp < TIPC_CRITICAL_IMPORTANCE)
 359                         msg_set_importance(msg, ++imp);
 360                 msg_set_errcode(msg, err);
 361                 buf->next = NULL;
 362         }
 363         return buf;
 364 }
 365
 366 static int port_print(struct tipc_port *p_ptr, char *buf, int len, int full_id)
 367 {
 368         struct publication *publ;
 369         int ret;
 370
 371         if (full_id)
 372                 ret = tipc_snprintf(buf, len, "<%u.%u.%u:%u>:",
 373                                     tipc_zone(tipc_own_addr),
 374                                     tipc_cluster(tipc_own_addr),
 375                                     tipc_node(tipc_own_addr), p_ptr->ref);
 376         else
 377                 ret = tipc_snprintf(buf, len, "%-10u:", p_ptr->ref);
 378
 379         if (p_ptr->connected) {
 380                 u32 dport = tipc_port_peerport(p_ptr);
 381                 u32 destnode = tipc_port_peernode(p_ptr);
 382
 383                 ret += tipc_snprintf(buf + ret, len - ret,
 384                                      " connected to <%u.%u.%u:%u>",
 385                                      tipc_zone(destnode),
 386                                      tipc_cluster(destnode),
 387                                      tipc_node(destnode), dport);
 388                 if (p_ptr->conn_type != 0)
 389                         ret += tipc_snprintf(buf + ret, len - ret,
 390                                              " via {%u,%u}", p_ptr->conn_type,
 391                                              p_ptr->conn_instance);
 392         } else if (p_ptr->published) {
 393                 ret += tipc_snprintf(buf + ret, len - ret, " bound to");
 394                 list_for_each_entry(publ, &p_ptr->publications, pport_list) {
 395                         if (publ->lower == publ->upper)
 396                                 ret += tipc_snprintf(buf + ret, len - ret,
 397                                                      " {%u,%u}", publ->type,
 398                                                      publ->lower);
 399                         else
 400                                 ret += tipc_snprintf(buf + ret, len - ret,
 401                                                      " {%u,%u,%u}", publ->type,
 402                                                      publ->lower, publ->upper);
 403                 }
 404         }
 405         ret += tipc_snprintf(buf + ret, len - ret, "\n");
 406         return ret;
 407 }
 408
 409 struct sk_buff *tipc_port_get_ports(void)
 410 {
 411         struct sk_buff *buf;
 412         struct tlv_desc *rep_tlv;
 413         char *pb;
 414         int pb_len;
 415         struct tipc_port *p_ptr;
 416         int str_len = 0;
 417
 418         buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN));
 419         if (!buf)
 420                 return NULL;
 421         rep_tlv = (struct tlv_desc *)buf->data;
 422         pb = TLV_DATA(rep_tlv);
 423         pb_len = ULTRA_STRING_MAX_LEN;
 424
 425         spin_lock_bh(&tipc_port_list_lock);
 426         list_for_each_entry(p_ptr, &ports, port_list) {
 427                 spin_lock_bh(p_ptr->lock);
 428                 str_len += port_print(p_ptr, pb, pb_len, 0);
 429                 spin_unlock_bh(p_ptr->lock);
 430         }
 431         spin_unlock_bh(&tipc_port_list_lock);
 432         str_len += 1;   /* for "\0" */
 433         skb_put(buf, TLV_SPACE(str_len));
 434         TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
 435
 436         return buf;
 437 }
 438
 439 void tipc_port_reinit(void)
 440 {
 441         struct tipc_port *p_ptr;
 442         struct tipc_msg *msg;
 443
 444         spin_lock_bh(&tipc_port_list_lock);
 445         list_for_each_entry(p_ptr, &ports, port_list) {
 446                 msg = &p_ptr->phdr;
 447                 msg_set_prevnode(msg, tipc_own_addr);
 448                 msg_set_orignode(msg, tipc_own_addr);
 449         }
 450         spin_unlock_bh(&tipc_port_list_lock);
 451 }
 452
 453 void tipc_acknowledge(u32 ref, u32 ack)
 454 {
 455         struct tipc_port *p_ptr;
 456         struct sk_buff *buf = NULL;
 457         struct tipc_msg *msg;
 458
 459         p_ptr = tipc_port_lock(ref);
 460         if (!p_ptr)
 461                 return;
 462         if (p_ptr->connected) {
 463                 p_ptr->conn_unacked -= ack;
 464                 buf = port_build_proto_msg(p_ptr, CONN_ACK, ack);
 465         }
 466         tipc_port_unlock(p_ptr);
 467         if (!buf)
 468                 return;
 469         msg = buf_msg(buf);
 470         tipc_link_xmit2(buf, msg_destnode(msg), msg_link_selector(msg));
 471 }
 472
 473 int tipc_publish(struct tipc_port *p_ptr, unsigned int scope,
 474                  struct tipc_name_seq const *seq)
 475 {
 476         struct publication *publ;
 477         u32 key;
 478
 479         if (p_ptr->connected)
 480                 return -EINVAL;
 481         key = p_ptr->ref + p_ptr->pub_count + 1;
 482         if (key == p_ptr->ref)
 483                 return -EADDRINUSE;
 484
 485         publ = tipc_nametbl_publish(seq->type, seq->lower, seq->upper,
 486                                     scope, p_ptr->ref, key);
 487         if (publ) {
 488                 list_add(&publ->pport_list, &p_ptr->publications);
 489                 p_ptr->pub_count++;
 490                 p_ptr->published = 1;
 491                 return 0;
 492         }
 493         return -EINVAL;
 494 }
 495
 496 int tipc_withdraw(struct tipc_port *p_ptr, unsigned int scope,
 497                   struct tipc_name_seq const *seq)
 498 {
 499         struct publication *publ;
 500         struct publication *tpubl;
 501         int res = -EINVAL;
 502
 503         if (!seq) {
 504                 list_for_each_entry_safe(publ, tpubl,
 505                                          &p_ptr->publications, pport_list) {
 506                         tipc_nametbl_withdraw(publ->type, publ->lower,
 507                                               publ->ref, publ->key);
 508                 }
 509                 res = 0;
 510         } else {
 511                 list_for_each_entry_safe(publ, tpubl,
 512                                          &p_ptr->publications, pport_list) {
 513                         if (publ->scope != scope)
 514                                 continue;
 515                         if (publ->type != seq->type)
 516                                 continue;
 517                         if (publ->lower != seq->lower)
 518                                 continue;
 519                         if (publ->upper != seq->upper)
 520                                 break;
 521                         tipc_nametbl_withdraw(publ->type, publ->lower,
 522                                               publ->ref, publ->key);
 523                         res = 0;
 524                         break;
 525                 }
 526         }
 527         if (list_empty(&p_ptr->publications))
 528                 p_ptr->published = 0;
 529         return res;
 530 }
 531
 532 int tipc_port_connect(u32 ref, struct tipc_portid const *peer)
 533 {
 534         struct tipc_port *p_ptr;
 535         int res;
 536
 537         p_ptr = tipc_port_lock(ref);
 538         if (!p_ptr)
 539                 return -EINVAL;
 540         res = __tipc_port_connect(ref, p_ptr, peer);
 541         tipc_port_unlock(p_ptr);
 542         return res;
 543 }
 544
 545 /*
 546  * __tipc_port_connect - connect to a remote peer
 547  *
 548  * Port must be locked.
 549  */
 550 int __tipc_port_connect(u32 ref, struct tipc_port *p_ptr,
 551                         struct tipc_portid const *peer)
 552 {
 553         struct tipc_msg *msg;
 554         int res = -EINVAL;
 555
 556         if (p_ptr->published || p_ptr->connected)
 557                 goto exit;
 558         if (!peer->ref)
 559                 goto exit;
 560
 561         msg = &p_ptr->phdr;
 562         msg_set_destnode(msg, peer->node);
 563         msg_set_destport(msg, peer->ref);
 564         msg_set_type(msg, TIPC_CONN_MSG);
 565         msg_set_lookup_scope(msg, 0);
 566         msg_set_hdr_sz(msg, SHORT_H_SIZE);
 567
 568         p_ptr->probing_interval = PROBING_INTERVAL;
 569         p_ptr->probing_state = TIPC_CONN_OK;
 570         p_ptr->connected = 1;
 571         k_start_timer(&p_ptr->timer, p_ptr->probing_interval);
 572
 573         tipc_nodesub_subscribe(&p_ptr->subscription, peer->node,
 574                           (void *)(unsigned long)ref,
 575                           (net_ev_handler)port_handle_node_down);
 576         res = 0;
 577 exit:
 578         p_ptr->max_pkt = tipc_node_get_mtu(peer->node, ref);
 579         return res;
 580 }
 581
 582 /*
 583  * __tipc_disconnect - disconnect port from peer
 584  *
 585  * Port must be locked.
 586  */
 587 int __tipc_port_disconnect(struct tipc_port *tp_ptr)
 588 {
 589         if (tp_ptr->connected) {
 590                 tp_ptr->connected = 0;
 591                 /* let timer expire on it's own to avoid deadlock! */
 592                 tipc_nodesub_unsubscribe(&tp_ptr->subscription);
 593                 return 0;
 594         }
 595
 596         return -ENOTCONN;
 597 }
 598
 599 /*
 600  * tipc_port_disconnect(): Disconnect port form peer.
 601  *                    This is a node local operation.
 602  */
 603 int tipc_port_disconnect(u32 ref)
 604 {
 605         struct tipc_port *p_ptr;
 606         int res;
 607
 608         p_ptr = tipc_port_lock(ref);
 609         if (!p_ptr)
 610                 return -EINVAL;
 611         res = __tipc_port_disconnect(p_ptr);
 612         tipc_port_unlock(p_ptr);
 613         return res;
 614 }
 615
 616 /*
 617  * tipc_port_shutdown(): Send a SHUTDOWN msg to peer and disconnect
 618  */
 619 int tipc_port_shutdown(u32 ref)
 620 {
 621         struct tipc_msg *msg;
 622         struct tipc_port *p_ptr;
 623         struct sk_buff *buf = NULL;
 624
 625         p_ptr = tipc_port_lock(ref);
 626         if (!p_ptr)
 627                 return -EINVAL;
 628
 629         buf = port_build_peer_abort_msg(p_ptr, TIPC_CONN_SHUTDOWN);
 630         tipc_port_unlock(p_ptr);
 631         msg = buf_msg(buf);
 632         tipc_link_xmit2(buf, msg_destnode(msg), msg_link_selector(msg));
 633         return tipc_port_disconnect(ref);
 634 }