1 /* 2 * net/tipc/link.c: TIPC link code 3 * 4 * Copyright (c) 1996-2007, Ericsson AB 5 * Copyright (c) 2004-2007, 2010-2011, 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 "link.h" 39 #include "port.h" 40 #include "name_distr.h" 41 #include "discover.h" 42 #include "config.h" 43 44 45 /* 46 * Out-of-range value for link session numbers 47 */ 48 49 #define INVALID_SESSION 0x10000 50 51 /* 52 * Link state events: 53 */ 54 55 #define STARTING_EVT 856384768 /* link processing trigger */ 56 #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */ 57 #define TIMEOUT_EVT 560817u /* link timer expired */ 58 59 /* 60 * The following two 'message types' is really just implementation 61 * data conveniently stored in the message header. 62 * They must not be considered part of the protocol 63 */ 64 #define OPEN_MSG 0 65 #define CLOSED_MSG 1 66 67 /* 68 * State value stored in 'exp_msg_count' 69 */ 70 71 #define START_CHANGEOVER 100000u 72 73 /** 74 * struct link_name - deconstructed link name 75 * @addr_local: network address of node at this end 76 * @if_local: name of interface at this end 77 * @addr_peer: network address of node at far end 78 * @if_peer: name of interface at far end 79 */ 80 81 struct link_name { 82 u32 addr_local; 83 char if_local[TIPC_MAX_IF_NAME]; 84 u32 addr_peer; 85 char if_peer[TIPC_MAX_IF_NAME]; 86 }; 87 88 static void link_handle_out_of_seq_msg(struct link *l_ptr, 89 struct sk_buff *buf); 90 static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf); 91 static int link_recv_changeover_msg(struct link **l_ptr, struct sk_buff **buf); 92 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance); 93 static int link_send_sections_long(struct tipc_port *sender, 94 struct iovec const *msg_sect, 95 u32 num_sect, unsigned int total_len, 96 u32 destnode); 97 static void link_check_defragm_bufs(struct link *l_ptr); 98 static void link_state_event(struct link *l_ptr, u32 event); 99 static void link_reset_statistics(struct link *l_ptr); 100 static void link_print(struct link *l_ptr, const char *str); 101 static void link_start(struct link *l_ptr); 102 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf); 103 104 /* 105 * Simple link routines 106 */ 107 108 static unsigned int align(unsigned int i) 109 { 110 return (i + 3) & ~3u; 111 } 112 113 static void link_init_max_pkt(struct link *l_ptr) 114 { 115 u32 max_pkt; 116 117 max_pkt = (l_ptr->b_ptr->mtu & ~3); 118 if (max_pkt > MAX_MSG_SIZE) 119 max_pkt = MAX_MSG_SIZE; 120 121 l_ptr->max_pkt_target = max_pkt; 122 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT) 123 l_ptr->max_pkt = l_ptr->max_pkt_target; 124 else 125 l_ptr->max_pkt = MAX_PKT_DEFAULT; 126 127 l_ptr->max_pkt_probes = 0; 128 } 129 130 static u32 link_next_sent(struct link *l_ptr) 131 { 132 if (l_ptr->next_out) 133 return msg_seqno(buf_msg(l_ptr->next_out)); 134 return mod(l_ptr->next_out_no); 135 } 136 137 static u32 link_last_sent(struct link *l_ptr) 138 { 139 return mod(link_next_sent(l_ptr) - 1); 140 } 141 142 /* 143 * Simple non-static link routines (i.e. referenced outside this file) 144 */ 145 146 int tipc_link_is_up(struct link *l_ptr) 147 { 148 if (!l_ptr) 149 return 0; 150 return link_working_working(l_ptr) || link_working_unknown(l_ptr); 151 } 152 153 int tipc_link_is_active(struct link *l_ptr) 154 { 155 return (l_ptr->owner->active_links[0] == l_ptr) || 156 (l_ptr->owner->active_links[1] == l_ptr); 157 } 158 159 /** 160 * link_name_validate - validate & (optionally) deconstruct link name 161 * @name - ptr to link name string 162 * @name_parts - ptr to area for link name components (or NULL if not needed) 163 * 164 * Returns 1 if link name is valid, otherwise 0. 165 */ 166 167 static int link_name_validate(const char *name, struct link_name *name_parts) 168 { 169 char name_copy[TIPC_MAX_LINK_NAME]; 170 char *addr_local; 171 char *if_local; 172 char *addr_peer; 173 char *if_peer; 174 char dummy; 175 u32 z_local, c_local, n_local; 176 u32 z_peer, c_peer, n_peer; 177 u32 if_local_len; 178 u32 if_peer_len; 179 180 /* copy link name & ensure length is OK */ 181 182 name_copy[TIPC_MAX_LINK_NAME - 1] = 0; 183 /* need above in case non-Posix strncpy() doesn't pad with nulls */ 184 strncpy(name_copy, name, TIPC_MAX_LINK_NAME); 185 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0) 186 return 0; 187 188 /* ensure all component parts of link name are present */ 189 190 addr_local = name_copy; 191 if_local = strchr(addr_local, ':'); 192 if (if_local == NULL) 193 return 0; 194 *(if_local++) = 0; 195 addr_peer = strchr(if_local, '-'); 196 if (addr_peer == NULL) 197 return 0; 198 *(addr_peer++) = 0; 199 if_local_len = addr_peer - if_local; 200 if_peer = strchr(addr_peer, ':'); 201 if (if_peer == NULL) 202 return 0; 203 *(if_peer++) = 0; 204 if_peer_len = strlen(if_peer) + 1; 205 206 /* validate component parts of link name */ 207 208 if ((sscanf(addr_local, "%u.%u.%u%c", 209 &z_local, &c_local, &n_local, &dummy) != 3) || 210 (sscanf(addr_peer, "%u.%u.%u%c", 211 &z_peer, &c_peer, &n_peer, &dummy) != 3) || 212 (z_local > 255) || (c_local > 4095) || (n_local > 4095) || 213 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) || 214 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) || 215 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) || 216 (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) || 217 (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1))) 218 return 0; 219 220 /* return link name components, if necessary */ 221 222 if (name_parts) { 223 name_parts->addr_local = tipc_addr(z_local, c_local, n_local); 224 strcpy(name_parts->if_local, if_local); 225 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer); 226 strcpy(name_parts->if_peer, if_peer); 227 } 228 return 1; 229 } 230 231 /** 232 * link_timeout - handle expiration of link timer 233 * @l_ptr: pointer to link 234 * 235 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict 236 * with tipc_link_delete(). (There is no risk that the node will be deleted by 237 * another thread because tipc_link_delete() always cancels the link timer before 238 * tipc_node_delete() is called.) 239 */ 240 241 static void link_timeout(struct link *l_ptr) 242 { 243 tipc_node_lock(l_ptr->owner); 244 245 /* update counters used in statistical profiling of send traffic */ 246 247 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size; 248 l_ptr->stats.queue_sz_counts++; 249 250 if (l_ptr->first_out) { 251 struct tipc_msg *msg = buf_msg(l_ptr->first_out); 252 u32 length = msg_size(msg); 253 254 if ((msg_user(msg) == MSG_FRAGMENTER) && 255 (msg_type(msg) == FIRST_FRAGMENT)) { 256 length = msg_size(msg_get_wrapped(msg)); 257 } 258 if (length) { 259 l_ptr->stats.msg_lengths_total += length; 260 l_ptr->stats.msg_length_counts++; 261 if (length <= 64) 262 l_ptr->stats.msg_length_profile[0]++; 263 else if (length <= 256) 264 l_ptr->stats.msg_length_profile[1]++; 265 else if (length <= 1024) 266 l_ptr->stats.msg_length_profile[2]++; 267 else if (length <= 4096) 268 l_ptr->stats.msg_length_profile[3]++; 269 else if (length <= 16384) 270 l_ptr->stats.msg_length_profile[4]++; 271 else if (length <= 32768) 272 l_ptr->stats.msg_length_profile[5]++; 273 else 274 l_ptr->stats.msg_length_profile[6]++; 275 } 276 } 277 278 /* do all other link processing performed on a periodic basis */ 279 280 link_check_defragm_bufs(l_ptr); 281 282 link_state_event(l_ptr, TIMEOUT_EVT); 283 284 if (l_ptr->next_out) 285 tipc_link_push_queue(l_ptr); 286 287 tipc_node_unlock(l_ptr->owner); 288 } 289 290 static void link_set_timer(struct link *l_ptr, u32 time) 291 { 292 k_start_timer(&l_ptr->timer, time); 293 } 294 295 /** 296 * tipc_link_create - create a new link 297 * @n_ptr: pointer to associated node 298 * @b_ptr: pointer to associated bearer 299 * @media_addr: media address to use when sending messages over link 300 * 301 * Returns pointer to link. 302 */ 303 304 struct link *tipc_link_create(struct tipc_node *n_ptr, 305 struct tipc_bearer *b_ptr, 306 const struct tipc_media_addr *media_addr) 307 { 308 struct link *l_ptr; 309 struct tipc_msg *msg; 310 char *if_name; 311 char addr_string[16]; 312 u32 peer = n_ptr->addr; 313 314 if (n_ptr->link_cnt >= 2) { 315 tipc_addr_string_fill(addr_string, n_ptr->addr); 316 err("Attempt to establish third link to %s\n", addr_string); 317 return NULL; 318 } 319 320 if (n_ptr->links[b_ptr->identity]) { 321 tipc_addr_string_fill(addr_string, n_ptr->addr); 322 err("Attempt to establish second link on <%s> to %s\n", 323 b_ptr->name, addr_string); 324 return NULL; 325 } 326 327 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC); 328 if (!l_ptr) { 329 warn("Link creation failed, no memory\n"); 330 return NULL; 331 } 332 333 l_ptr->addr = peer; 334 if_name = strchr(b_ptr->name, ':') + 1; 335 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown", 336 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr), 337 tipc_node(tipc_own_addr), 338 if_name, 339 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer)); 340 /* note: peer i/f name is updated by reset/activate message */ 341 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr)); 342 l_ptr->owner = n_ptr; 343 l_ptr->checkpoint = 1; 344 l_ptr->peer_session = INVALID_SESSION; 345 l_ptr->b_ptr = b_ptr; 346 link_set_supervision_props(l_ptr, b_ptr->media->tolerance); 347 l_ptr->state = RESET_UNKNOWN; 348 349 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg; 350 msg = l_ptr->pmsg; 351 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr); 352 msg_set_size(msg, sizeof(l_ptr->proto_msg)); 353 msg_set_session(msg, (tipc_random & 0xffff)); 354 msg_set_bearer_id(msg, b_ptr->identity); 355 strcpy((char *)msg_data(msg), if_name); 356 357 l_ptr->priority = b_ptr->priority; 358 tipc_link_set_queue_limits(l_ptr, b_ptr->media->window); 359 360 link_init_max_pkt(l_ptr); 361 362 l_ptr->next_out_no = 1; 363 INIT_LIST_HEAD(&l_ptr->waiting_ports); 364 365 link_reset_statistics(l_ptr); 366 367 tipc_node_attach_link(n_ptr, l_ptr); 368 369 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr); 370 list_add_tail(&l_ptr->link_list, &b_ptr->links); 371 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr); 372 373 return l_ptr; 374 } 375 376 /** 377 * tipc_link_delete - delete a link 378 * @l_ptr: pointer to link 379 * 380 * Note: 'tipc_net_lock' is write_locked, bearer is locked. 381 * This routine must not grab the node lock until after link timer cancellation 382 * to avoid a potential deadlock situation. 383 */ 384 385 void tipc_link_delete(struct link *l_ptr) 386 { 387 if (!l_ptr) { 388 err("Attempt to delete non-existent link\n"); 389 return; 390 } 391 392 k_cancel_timer(&l_ptr->timer); 393 394 tipc_node_lock(l_ptr->owner); 395 tipc_link_reset(l_ptr); 396 tipc_node_detach_link(l_ptr->owner, l_ptr); 397 tipc_link_stop(l_ptr); 398 list_del_init(&l_ptr->link_list); 399 tipc_node_unlock(l_ptr->owner); 400 k_term_timer(&l_ptr->timer); 401 kfree(l_ptr); 402 } 403 404 static void link_start(struct link *l_ptr) 405 { 406 tipc_node_lock(l_ptr->owner); 407 link_state_event(l_ptr, STARTING_EVT); 408 tipc_node_unlock(l_ptr->owner); 409 } 410 411 /** 412 * link_schedule_port - schedule port for deferred sending 413 * @l_ptr: pointer to link 414 * @origport: reference to sending port 415 * @sz: amount of data to be sent 416 * 417 * Schedules port for renewed sending of messages after link congestion 418 * has abated. 419 */ 420 421 static int link_schedule_port(struct link *l_ptr, u32 origport, u32 sz) 422 { 423 struct tipc_port *p_ptr; 424 425 spin_lock_bh(&tipc_port_list_lock); 426 p_ptr = tipc_port_lock(origport); 427 if (p_ptr) { 428 if (!p_ptr->wakeup) 429 goto exit; 430 if (!list_empty(&p_ptr->wait_list)) 431 goto exit; 432 p_ptr->congested = 1; 433 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt); 434 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports); 435 l_ptr->stats.link_congs++; 436 exit: 437 tipc_port_unlock(p_ptr); 438 } 439 spin_unlock_bh(&tipc_port_list_lock); 440 return -ELINKCONG; 441 } 442 443 void tipc_link_wakeup_ports(struct link *l_ptr, int all) 444 { 445 struct tipc_port *p_ptr; 446 struct tipc_port *temp_p_ptr; 447 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size; 448 449 if (all) 450 win = 100000; 451 if (win <= 0) 452 return; 453 if (!spin_trylock_bh(&tipc_port_list_lock)) 454 return; 455 if (link_congested(l_ptr)) 456 goto exit; 457 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports, 458 wait_list) { 459 if (win <= 0) 460 break; 461 list_del_init(&p_ptr->wait_list); 462 spin_lock_bh(p_ptr->lock); 463 p_ptr->congested = 0; 464 p_ptr->wakeup(p_ptr); 465 win -= p_ptr->waiting_pkts; 466 spin_unlock_bh(p_ptr->lock); 467 } 468 469 exit: 470 spin_unlock_bh(&tipc_port_list_lock); 471 } 472 473 /** 474 * link_release_outqueue - purge link's outbound message queue 475 * @l_ptr: pointer to link 476 */ 477 478 static void link_release_outqueue(struct link *l_ptr) 479 { 480 struct sk_buff *buf = l_ptr->first_out; 481 struct sk_buff *next; 482 483 while (buf) { 484 next = buf->next; 485 buf_discard(buf); 486 buf = next; 487 } 488 l_ptr->first_out = NULL; 489 l_ptr->out_queue_size = 0; 490 } 491 492 /** 493 * tipc_link_reset_fragments - purge link's inbound message fragments queue 494 * @l_ptr: pointer to link 495 */ 496 497 void tipc_link_reset_fragments(struct link *l_ptr) 498 { 499 struct sk_buff *buf = l_ptr->defragm_buf; 500 struct sk_buff *next; 501 502 while (buf) { 503 next = buf->next; 504 buf_discard(buf); 505 buf = next; 506 } 507 l_ptr->defragm_buf = NULL; 508 } 509 510 /** 511 * tipc_link_stop - purge all inbound and outbound messages associated with link 512 * @l_ptr: pointer to link 513 */ 514 515 void tipc_link_stop(struct link *l_ptr) 516 { 517 struct sk_buff *buf; 518 struct sk_buff *next; 519 520 buf = l_ptr->oldest_deferred_in; 521 while (buf) { 522 next = buf->next; 523 buf_discard(buf); 524 buf = next; 525 } 526 527 buf = l_ptr->first_out; 528 while (buf) { 529 next = buf->next; 530 buf_discard(buf); 531 buf = next; 532 } 533 534 tipc_link_reset_fragments(l_ptr); 535 536 buf_discard(l_ptr->proto_msg_queue); 537 l_ptr->proto_msg_queue = NULL; 538 } 539 540 void tipc_link_reset(struct link *l_ptr) 541 { 542 struct sk_buff *buf; 543 u32 prev_state = l_ptr->state; 544 u32 checkpoint = l_ptr->next_in_no; 545 int was_active_link = tipc_link_is_active(l_ptr); 546 547 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff)); 548 549 /* Link is down, accept any session */ 550 l_ptr->peer_session = INVALID_SESSION; 551 552 /* Prepare for max packet size negotiation */ 553 link_init_max_pkt(l_ptr); 554 555 l_ptr->state = RESET_UNKNOWN; 556 557 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET)) 558 return; 559 560 tipc_node_link_down(l_ptr->owner, l_ptr); 561 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr); 562 563 if (was_active_link && tipc_node_active_links(l_ptr->owner) && 564 l_ptr->owner->permit_changeover) { 565 l_ptr->reset_checkpoint = checkpoint; 566 l_ptr->exp_msg_count = START_CHANGEOVER; 567 } 568 569 /* Clean up all queues: */ 570 571 link_release_outqueue(l_ptr); 572 buf_discard(l_ptr->proto_msg_queue); 573 l_ptr->proto_msg_queue = NULL; 574 buf = l_ptr->oldest_deferred_in; 575 while (buf) { 576 struct sk_buff *next = buf->next; 577 buf_discard(buf); 578 buf = next; 579 } 580 if (!list_empty(&l_ptr->waiting_ports)) 581 tipc_link_wakeup_ports(l_ptr, 1); 582 583 l_ptr->retransm_queue_head = 0; 584 l_ptr->retransm_queue_size = 0; 585 l_ptr->last_out = NULL; 586 l_ptr->first_out = NULL; 587 l_ptr->next_out = NULL; 588 l_ptr->unacked_window = 0; 589 l_ptr->checkpoint = 1; 590 l_ptr->next_out_no = 1; 591 l_ptr->deferred_inqueue_sz = 0; 592 l_ptr->oldest_deferred_in = NULL; 593 l_ptr->newest_deferred_in = NULL; 594 l_ptr->fsm_msg_cnt = 0; 595 l_ptr->stale_count = 0; 596 link_reset_statistics(l_ptr); 597 } 598 599 600 static void link_activate(struct link *l_ptr) 601 { 602 l_ptr->next_in_no = l_ptr->stats.recv_info = 1; 603 tipc_node_link_up(l_ptr->owner, l_ptr); 604 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr); 605 } 606 607 /** 608 * link_state_event - link finite state machine 609 * @l_ptr: pointer to link 610 * @event: state machine event to process 611 */ 612 613 static void link_state_event(struct link *l_ptr, unsigned event) 614 { 615 struct link *other; 616 u32 cont_intv = l_ptr->continuity_interval; 617 618 if (!l_ptr->started && (event != STARTING_EVT)) 619 return; /* Not yet. */ 620 621 if (link_blocked(l_ptr)) { 622 if (event == TIMEOUT_EVT) 623 link_set_timer(l_ptr, cont_intv); 624 return; /* Changeover going on */ 625 } 626 627 switch (l_ptr->state) { 628 case WORKING_WORKING: 629 switch (event) { 630 case TRAFFIC_MSG_EVT: 631 case ACTIVATE_MSG: 632 break; 633 case TIMEOUT_EVT: 634 if (l_ptr->next_in_no != l_ptr->checkpoint) { 635 l_ptr->checkpoint = l_ptr->next_in_no; 636 if (tipc_bclink_acks_missing(l_ptr->owner)) { 637 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 638 0, 0, 0, 0, 0); 639 l_ptr->fsm_msg_cnt++; 640 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) { 641 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 642 1, 0, 0, 0, 0); 643 l_ptr->fsm_msg_cnt++; 644 } 645 link_set_timer(l_ptr, cont_intv); 646 break; 647 } 648 l_ptr->state = WORKING_UNKNOWN; 649 l_ptr->fsm_msg_cnt = 0; 650 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); 651 l_ptr->fsm_msg_cnt++; 652 link_set_timer(l_ptr, cont_intv / 4); 653 break; 654 case RESET_MSG: 655 info("Resetting link <%s>, requested by peer\n", 656 l_ptr->name); 657 tipc_link_reset(l_ptr); 658 l_ptr->state = RESET_RESET; 659 l_ptr->fsm_msg_cnt = 0; 660 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); 661 l_ptr->fsm_msg_cnt++; 662 link_set_timer(l_ptr, cont_intv); 663 break; 664 default: 665 err("Unknown link event %u in WW state\n", event); 666 } 667 break; 668 case WORKING_UNKNOWN: 669 switch (event) { 670 case TRAFFIC_MSG_EVT: 671 case ACTIVATE_MSG: 672 l_ptr->state = WORKING_WORKING; 673 l_ptr->fsm_msg_cnt = 0; 674 link_set_timer(l_ptr, cont_intv); 675 break; 676 case RESET_MSG: 677 info("Resetting link <%s>, requested by peer " 678 "while probing\n", l_ptr->name); 679 tipc_link_reset(l_ptr); 680 l_ptr->state = RESET_RESET; 681 l_ptr->fsm_msg_cnt = 0; 682 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); 683 l_ptr->fsm_msg_cnt++; 684 link_set_timer(l_ptr, cont_intv); 685 break; 686 case TIMEOUT_EVT: 687 if (l_ptr->next_in_no != l_ptr->checkpoint) { 688 l_ptr->state = WORKING_WORKING; 689 l_ptr->fsm_msg_cnt = 0; 690 l_ptr->checkpoint = l_ptr->next_in_no; 691 if (tipc_bclink_acks_missing(l_ptr->owner)) { 692 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 693 0, 0, 0, 0, 0); 694 l_ptr->fsm_msg_cnt++; 695 } 696 link_set_timer(l_ptr, cont_intv); 697 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) { 698 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 699 1, 0, 0, 0, 0); 700 l_ptr->fsm_msg_cnt++; 701 link_set_timer(l_ptr, cont_intv / 4); 702 } else { /* Link has failed */ 703 warn("Resetting link <%s>, peer not responding\n", 704 l_ptr->name); 705 tipc_link_reset(l_ptr); 706 l_ptr->state = RESET_UNKNOWN; 707 l_ptr->fsm_msg_cnt = 0; 708 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 709 0, 0, 0, 0, 0); 710 l_ptr->fsm_msg_cnt++; 711 link_set_timer(l_ptr, cont_intv); 712 } 713 break; 714 default: 715 err("Unknown link event %u in WU state\n", event); 716 } 717 break; 718 case RESET_UNKNOWN: 719 switch (event) { 720 case TRAFFIC_MSG_EVT: 721 break; 722 case ACTIVATE_MSG: 723 other = l_ptr->owner->active_links[0]; 724 if (other && link_working_unknown(other)) 725 break; 726 l_ptr->state = WORKING_WORKING; 727 l_ptr->fsm_msg_cnt = 0; 728 link_activate(l_ptr); 729 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); 730 l_ptr->fsm_msg_cnt++; 731 link_set_timer(l_ptr, cont_intv); 732 break; 733 case RESET_MSG: 734 l_ptr->state = RESET_RESET; 735 l_ptr->fsm_msg_cnt = 0; 736 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0); 737 l_ptr->fsm_msg_cnt++; 738 link_set_timer(l_ptr, cont_intv); 739 break; 740 case STARTING_EVT: 741 l_ptr->started = 1; 742 /* fall through */ 743 case TIMEOUT_EVT: 744 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0); 745 l_ptr->fsm_msg_cnt++; 746 link_set_timer(l_ptr, cont_intv); 747 break; 748 default: 749 err("Unknown link event %u in RU state\n", event); 750 } 751 break; 752 case RESET_RESET: 753 switch (event) { 754 case TRAFFIC_MSG_EVT: 755 case ACTIVATE_MSG: 756 other = l_ptr->owner->active_links[0]; 757 if (other && link_working_unknown(other)) 758 break; 759 l_ptr->state = WORKING_WORKING; 760 l_ptr->fsm_msg_cnt = 0; 761 link_activate(l_ptr); 762 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); 763 l_ptr->fsm_msg_cnt++; 764 link_set_timer(l_ptr, cont_intv); 765 break; 766 case RESET_MSG: 767 break; 768 case TIMEOUT_EVT: 769 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); 770 l_ptr->fsm_msg_cnt++; 771 link_set_timer(l_ptr, cont_intv); 772 break; 773 default: 774 err("Unknown link event %u in RR state\n", event); 775 } 776 break; 777 default: 778 err("Unknown link state %u/%u\n", l_ptr->state, event); 779 } 780 } 781 782 /* 783 * link_bundle_buf(): Append contents of a buffer to 784 * the tail of an existing one. 785 */ 786 787 static int link_bundle_buf(struct link *l_ptr, 788 struct sk_buff *bundler, 789 struct sk_buff *buf) 790 { 791 struct tipc_msg *bundler_msg = buf_msg(bundler); 792 struct tipc_msg *msg = buf_msg(buf); 793 u32 size = msg_size(msg); 794 u32 bundle_size = msg_size(bundler_msg); 795 u32 to_pos = align(bundle_size); 796 u32 pad = to_pos - bundle_size; 797 798 if (msg_user(bundler_msg) != MSG_BUNDLER) 799 return 0; 800 if (msg_type(bundler_msg) != OPEN_MSG) 801 return 0; 802 if (skb_tailroom(bundler) < (pad + size)) 803 return 0; 804 if (l_ptr->max_pkt < (to_pos + size)) 805 return 0; 806 807 skb_put(bundler, pad + size); 808 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size); 809 msg_set_size(bundler_msg, to_pos + size); 810 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1); 811 buf_discard(buf); 812 l_ptr->stats.sent_bundled++; 813 return 1; 814 } 815 816 static void link_add_to_outqueue(struct link *l_ptr, 817 struct sk_buff *buf, 818 struct tipc_msg *msg) 819 { 820 u32 ack = mod(l_ptr->next_in_no - 1); 821 u32 seqno = mod(l_ptr->next_out_no++); 822 823 msg_set_word(msg, 2, ((ack << 16) | seqno)); 824 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 825 buf->next = NULL; 826 if (l_ptr->first_out) { 827 l_ptr->last_out->next = buf; 828 l_ptr->last_out = buf; 829 } else 830 l_ptr->first_out = l_ptr->last_out = buf; 831 832 l_ptr->out_queue_size++; 833 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz) 834 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size; 835 } 836 837 static void link_add_chain_to_outqueue(struct link *l_ptr, 838 struct sk_buff *buf_chain, 839 u32 long_msgno) 840 { 841 struct sk_buff *buf; 842 struct tipc_msg *msg; 843 844 if (!l_ptr->next_out) 845 l_ptr->next_out = buf_chain; 846 while (buf_chain) { 847 buf = buf_chain; 848 buf_chain = buf_chain->next; 849 850 msg = buf_msg(buf); 851 msg_set_long_msgno(msg, long_msgno); 852 link_add_to_outqueue(l_ptr, buf, msg); 853 } 854 } 855 856 /* 857 * tipc_link_send_buf() is the 'full path' for messages, called from 858 * inside TIPC when the 'fast path' in tipc_send_buf 859 * has failed, and from link_send() 860 */ 861 862 int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf) 863 { 864 struct tipc_msg *msg = buf_msg(buf); 865 u32 size = msg_size(msg); 866 u32 dsz = msg_data_sz(msg); 867 u32 queue_size = l_ptr->out_queue_size; 868 u32 imp = tipc_msg_tot_importance(msg); 869 u32 queue_limit = l_ptr->queue_limit[imp]; 870 u32 max_packet = l_ptr->max_pkt; 871 872 msg_set_prevnode(msg, tipc_own_addr); /* If routed message */ 873 874 /* Match msg importance against queue limits: */ 875 876 if (unlikely(queue_size >= queue_limit)) { 877 if (imp <= TIPC_CRITICAL_IMPORTANCE) { 878 link_schedule_port(l_ptr, msg_origport(msg), size); 879 buf_discard(buf); 880 return -ELINKCONG; 881 } 882 buf_discard(buf); 883 if (imp > CONN_MANAGER) { 884 warn("Resetting link <%s>, send queue full", l_ptr->name); 885 tipc_link_reset(l_ptr); 886 } 887 return dsz; 888 } 889 890 /* Fragmentation needed ? */ 891 892 if (size > max_packet) 893 return link_send_long_buf(l_ptr, buf); 894 895 /* Packet can be queued or sent: */ 896 897 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) && 898 !link_congested(l_ptr))) { 899 link_add_to_outqueue(l_ptr, buf, msg); 900 901 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) { 902 l_ptr->unacked_window = 0; 903 } else { 904 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 905 l_ptr->stats.bearer_congs++; 906 l_ptr->next_out = buf; 907 } 908 return dsz; 909 } 910 /* Congestion: can message be bundled ?: */ 911 912 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) && 913 (msg_user(msg) != MSG_FRAGMENTER)) { 914 915 /* Try adding message to an existing bundle */ 916 917 if (l_ptr->next_out && 918 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) { 919 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr); 920 return dsz; 921 } 922 923 /* Try creating a new bundle */ 924 925 if (size <= max_packet * 2 / 3) { 926 struct sk_buff *bundler = tipc_buf_acquire(max_packet); 927 struct tipc_msg bundler_hdr; 928 929 if (bundler) { 930 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG, 931 INT_H_SIZE, l_ptr->addr); 932 skb_copy_to_linear_data(bundler, &bundler_hdr, 933 INT_H_SIZE); 934 skb_trim(bundler, INT_H_SIZE); 935 link_bundle_buf(l_ptr, bundler, buf); 936 buf = bundler; 937 msg = buf_msg(buf); 938 l_ptr->stats.sent_bundles++; 939 } 940 } 941 } 942 if (!l_ptr->next_out) 943 l_ptr->next_out = buf; 944 link_add_to_outqueue(l_ptr, buf, msg); 945 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr); 946 return dsz; 947 } 948 949 /* 950 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has 951 * not been selected yet, and the the owner node is not locked 952 * Called by TIPC internal users, e.g. the name distributor 953 */ 954 955 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector) 956 { 957 struct link *l_ptr; 958 struct tipc_node *n_ptr; 959 int res = -ELINKCONG; 960 961 read_lock_bh(&tipc_net_lock); 962 n_ptr = tipc_node_find(dest); 963 if (n_ptr) { 964 tipc_node_lock(n_ptr); 965 l_ptr = n_ptr->active_links[selector & 1]; 966 if (l_ptr) 967 res = tipc_link_send_buf(l_ptr, buf); 968 else 969 buf_discard(buf); 970 tipc_node_unlock(n_ptr); 971 } else { 972 buf_discard(buf); 973 } 974 read_unlock_bh(&tipc_net_lock); 975 return res; 976 } 977 978 /* 979 * tipc_link_send_names - send name table entries to new neighbor 980 * 981 * Send routine for bulk delivery of name table messages when contact 982 * with a new neighbor occurs. No link congestion checking is performed 983 * because name table messages *must* be delivered. The messages must be 984 * small enough not to require fragmentation. 985 * Called without any locks held. 986 */ 987 988 void tipc_link_send_names(struct list_head *message_list, u32 dest) 989 { 990 struct tipc_node *n_ptr; 991 struct link *l_ptr; 992 struct sk_buff *buf; 993 struct sk_buff *temp_buf; 994 995 if (list_empty(message_list)) 996 return; 997 998 read_lock_bh(&tipc_net_lock); 999 n_ptr = tipc_node_find(dest); 1000 if (n_ptr) { 1001 tipc_node_lock(n_ptr); 1002 l_ptr = n_ptr->active_links[0]; 1003 if (l_ptr) { 1004 /* convert circular list to linear list */ 1005 ((struct sk_buff *)message_list->prev)->next = NULL; 1006 link_add_chain_to_outqueue(l_ptr, 1007 (struct sk_buff *)message_list->next, 0); 1008 tipc_link_push_queue(l_ptr); 1009 INIT_LIST_HEAD(message_list); 1010 } 1011 tipc_node_unlock(n_ptr); 1012 } 1013 read_unlock_bh(&tipc_net_lock); 1014 1015 /* discard the messages if they couldn't be sent */ 1016 1017 list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) { 1018 list_del((struct list_head *)buf); 1019 buf_discard(buf); 1020 } 1021 } 1022 1023 /* 1024 * link_send_buf_fast: Entry for data messages where the 1025 * destination link is known and the header is complete, 1026 * inclusive total message length. Very time critical. 1027 * Link is locked. Returns user data length. 1028 */ 1029 1030 static int link_send_buf_fast(struct link *l_ptr, struct sk_buff *buf, 1031 u32 *used_max_pkt) 1032 { 1033 struct tipc_msg *msg = buf_msg(buf); 1034 int res = msg_data_sz(msg); 1035 1036 if (likely(!link_congested(l_ptr))) { 1037 if (likely(msg_size(msg) <= l_ptr->max_pkt)) { 1038 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) { 1039 link_add_to_outqueue(l_ptr, buf, msg); 1040 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, 1041 &l_ptr->media_addr))) { 1042 l_ptr->unacked_window = 0; 1043 return res; 1044 } 1045 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 1046 l_ptr->stats.bearer_congs++; 1047 l_ptr->next_out = buf; 1048 return res; 1049 } 1050 } else 1051 *used_max_pkt = l_ptr->max_pkt; 1052 } 1053 return tipc_link_send_buf(l_ptr, buf); /* All other cases */ 1054 } 1055 1056 /* 1057 * tipc_send_buf_fast: Entry for data messages where the 1058 * destination node is known and the header is complete, 1059 * inclusive total message length. 1060 * Returns user data length. 1061 */ 1062 int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode) 1063 { 1064 struct link *l_ptr; 1065 struct tipc_node *n_ptr; 1066 int res; 1067 u32 selector = msg_origport(buf_msg(buf)) & 1; 1068 u32 dummy; 1069 1070 read_lock_bh(&tipc_net_lock); 1071 n_ptr = tipc_node_find(destnode); 1072 if (likely(n_ptr)) { 1073 tipc_node_lock(n_ptr); 1074 l_ptr = n_ptr->active_links[selector]; 1075 if (likely(l_ptr)) { 1076 res = link_send_buf_fast(l_ptr, buf, &dummy); 1077 tipc_node_unlock(n_ptr); 1078 read_unlock_bh(&tipc_net_lock); 1079 return res; 1080 } 1081 tipc_node_unlock(n_ptr); 1082 } 1083 read_unlock_bh(&tipc_net_lock); 1084 res = msg_data_sz(buf_msg(buf)); 1085 tipc_reject_msg(buf, TIPC_ERR_NO_NODE); 1086 return res; 1087 } 1088 1089 1090 /* 1091 * tipc_link_send_sections_fast: Entry for messages where the 1092 * destination processor is known and the header is complete, 1093 * except for total message length. 1094 * Returns user data length or errno. 1095 */ 1096 int tipc_link_send_sections_fast(struct tipc_port *sender, 1097 struct iovec const *msg_sect, 1098 const u32 num_sect, 1099 unsigned int total_len, 1100 u32 destaddr) 1101 { 1102 struct tipc_msg *hdr = &sender->phdr; 1103 struct link *l_ptr; 1104 struct sk_buff *buf; 1105 struct tipc_node *node; 1106 int res; 1107 u32 selector = msg_origport(hdr) & 1; 1108 1109 again: 1110 /* 1111 * Try building message using port's max_pkt hint. 1112 * (Must not hold any locks while building message.) 1113 */ 1114 1115 res = tipc_msg_build(hdr, msg_sect, num_sect, total_len, 1116 sender->max_pkt, !sender->user_port, &buf); 1117 1118 read_lock_bh(&tipc_net_lock); 1119 node = tipc_node_find(destaddr); 1120 if (likely(node)) { 1121 tipc_node_lock(node); 1122 l_ptr = node->active_links[selector]; 1123 if (likely(l_ptr)) { 1124 if (likely(buf)) { 1125 res = link_send_buf_fast(l_ptr, buf, 1126 &sender->max_pkt); 1127 exit: 1128 tipc_node_unlock(node); 1129 read_unlock_bh(&tipc_net_lock); 1130 return res; 1131 } 1132 1133 /* Exit if build request was invalid */ 1134 1135 if (unlikely(res < 0)) 1136 goto exit; 1137 1138 /* Exit if link (or bearer) is congested */ 1139 1140 if (link_congested(l_ptr) || 1141 !list_empty(&l_ptr->b_ptr->cong_links)) { 1142 res = link_schedule_port(l_ptr, 1143 sender->ref, res); 1144 goto exit; 1145 } 1146 1147 /* 1148 * Message size exceeds max_pkt hint; update hint, 1149 * then re-try fast path or fragment the message 1150 */ 1151 1152 sender->max_pkt = l_ptr->max_pkt; 1153 tipc_node_unlock(node); 1154 read_unlock_bh(&tipc_net_lock); 1155 1156 1157 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt) 1158 goto again; 1159 1160 return link_send_sections_long(sender, msg_sect, 1161 num_sect, total_len, 1162 destaddr); 1163 } 1164 tipc_node_unlock(node); 1165 } 1166 read_unlock_bh(&tipc_net_lock); 1167 1168 /* Couldn't find a link to the destination node */ 1169 1170 if (buf) 1171 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE); 1172 if (res >= 0) 1173 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect, 1174 total_len, TIPC_ERR_NO_NODE); 1175 return res; 1176 } 1177 1178 /* 1179 * link_send_sections_long(): Entry for long messages where the 1180 * destination node is known and the header is complete, 1181 * inclusive total message length. 1182 * Link and bearer congestion status have been checked to be ok, 1183 * and are ignored if they change. 1184 * 1185 * Note that fragments do not use the full link MTU so that they won't have 1186 * to undergo refragmentation if link changeover causes them to be sent 1187 * over another link with an additional tunnel header added as prefix. 1188 * (Refragmentation will still occur if the other link has a smaller MTU.) 1189 * 1190 * Returns user data length or errno. 1191 */ 1192 static int link_send_sections_long(struct tipc_port *sender, 1193 struct iovec const *msg_sect, 1194 u32 num_sect, 1195 unsigned int total_len, 1196 u32 destaddr) 1197 { 1198 struct link *l_ptr; 1199 struct tipc_node *node; 1200 struct tipc_msg *hdr = &sender->phdr; 1201 u32 dsz = total_len; 1202 u32 max_pkt, fragm_sz, rest; 1203 struct tipc_msg fragm_hdr; 1204 struct sk_buff *buf, *buf_chain, *prev; 1205 u32 fragm_crs, fragm_rest, hsz, sect_rest; 1206 const unchar *sect_crs; 1207 int curr_sect; 1208 u32 fragm_no; 1209 1210 again: 1211 fragm_no = 1; 1212 max_pkt = sender->max_pkt - INT_H_SIZE; 1213 /* leave room for tunnel header in case of link changeover */ 1214 fragm_sz = max_pkt - INT_H_SIZE; 1215 /* leave room for fragmentation header in each fragment */ 1216 rest = dsz; 1217 fragm_crs = 0; 1218 fragm_rest = 0; 1219 sect_rest = 0; 1220 sect_crs = NULL; 1221 curr_sect = -1; 1222 1223 /* Prepare reusable fragment header: */ 1224 1225 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT, 1226 INT_H_SIZE, msg_destnode(hdr)); 1227 msg_set_size(&fragm_hdr, max_pkt); 1228 msg_set_fragm_no(&fragm_hdr, 1); 1229 1230 /* Prepare header of first fragment: */ 1231 1232 buf_chain = buf = tipc_buf_acquire(max_pkt); 1233 if (!buf) 1234 return -ENOMEM; 1235 buf->next = NULL; 1236 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE); 1237 hsz = msg_hdr_sz(hdr); 1238 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz); 1239 1240 /* Chop up message: */ 1241 1242 fragm_crs = INT_H_SIZE + hsz; 1243 fragm_rest = fragm_sz - hsz; 1244 1245 do { /* For all sections */ 1246 u32 sz; 1247 1248 if (!sect_rest) { 1249 sect_rest = msg_sect[++curr_sect].iov_len; 1250 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base; 1251 } 1252 1253 if (sect_rest < fragm_rest) 1254 sz = sect_rest; 1255 else 1256 sz = fragm_rest; 1257 1258 if (likely(!sender->user_port)) { 1259 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) { 1260 error: 1261 for (; buf_chain; buf_chain = buf) { 1262 buf = buf_chain->next; 1263 buf_discard(buf_chain); 1264 } 1265 return -EFAULT; 1266 } 1267 } else 1268 skb_copy_to_linear_data_offset(buf, fragm_crs, 1269 sect_crs, sz); 1270 sect_crs += sz; 1271 sect_rest -= sz; 1272 fragm_crs += sz; 1273 fragm_rest -= sz; 1274 rest -= sz; 1275 1276 if (!fragm_rest && rest) { 1277 1278 /* Initiate new fragment: */ 1279 if (rest <= fragm_sz) { 1280 fragm_sz = rest; 1281 msg_set_type(&fragm_hdr, LAST_FRAGMENT); 1282 } else { 1283 msg_set_type(&fragm_hdr, FRAGMENT); 1284 } 1285 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE); 1286 msg_set_fragm_no(&fragm_hdr, ++fragm_no); 1287 prev = buf; 1288 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE); 1289 if (!buf) 1290 goto error; 1291 1292 buf->next = NULL; 1293 prev->next = buf; 1294 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE); 1295 fragm_crs = INT_H_SIZE; 1296 fragm_rest = fragm_sz; 1297 } 1298 } while (rest > 0); 1299 1300 /* 1301 * Now we have a buffer chain. Select a link and check 1302 * that packet size is still OK 1303 */ 1304 node = tipc_node_find(destaddr); 1305 if (likely(node)) { 1306 tipc_node_lock(node); 1307 l_ptr = node->active_links[sender->ref & 1]; 1308 if (!l_ptr) { 1309 tipc_node_unlock(node); 1310 goto reject; 1311 } 1312 if (l_ptr->max_pkt < max_pkt) { 1313 sender->max_pkt = l_ptr->max_pkt; 1314 tipc_node_unlock(node); 1315 for (; buf_chain; buf_chain = buf) { 1316 buf = buf_chain->next; 1317 buf_discard(buf_chain); 1318 } 1319 goto again; 1320 } 1321 } else { 1322 reject: 1323 for (; buf_chain; buf_chain = buf) { 1324 buf = buf_chain->next; 1325 buf_discard(buf_chain); 1326 } 1327 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect, 1328 total_len, TIPC_ERR_NO_NODE); 1329 } 1330 1331 /* Append chain of fragments to send queue & send them */ 1332 1333 l_ptr->long_msg_seq_no++; 1334 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no); 1335 l_ptr->stats.sent_fragments += fragm_no; 1336 l_ptr->stats.sent_fragmented++; 1337 tipc_link_push_queue(l_ptr); 1338 tipc_node_unlock(node); 1339 return dsz; 1340 } 1341 1342 /* 1343 * tipc_link_push_packet: Push one unsent packet to the media 1344 */ 1345 u32 tipc_link_push_packet(struct link *l_ptr) 1346 { 1347 struct sk_buff *buf = l_ptr->first_out; 1348 u32 r_q_size = l_ptr->retransm_queue_size; 1349 u32 r_q_head = l_ptr->retransm_queue_head; 1350 1351 /* Step to position where retransmission failed, if any, */ 1352 /* consider that buffers may have been released in meantime */ 1353 1354 if (r_q_size && buf) { 1355 u32 last = lesser(mod(r_q_head + r_q_size), 1356 link_last_sent(l_ptr)); 1357 u32 first = msg_seqno(buf_msg(buf)); 1358 1359 while (buf && less(first, r_q_head)) { 1360 first = mod(first + 1); 1361 buf = buf->next; 1362 } 1363 l_ptr->retransm_queue_head = r_q_head = first; 1364 l_ptr->retransm_queue_size = r_q_size = mod(last - first); 1365 } 1366 1367 /* Continue retransmission now, if there is anything: */ 1368 1369 if (r_q_size && buf) { 1370 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1)); 1371 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in); 1372 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1373 l_ptr->retransm_queue_head = mod(++r_q_head); 1374 l_ptr->retransm_queue_size = --r_q_size; 1375 l_ptr->stats.retransmitted++; 1376 return 0; 1377 } else { 1378 l_ptr->stats.bearer_congs++; 1379 return PUSH_FAILED; 1380 } 1381 } 1382 1383 /* Send deferred protocol message, if any: */ 1384 1385 buf = l_ptr->proto_msg_queue; 1386 if (buf) { 1387 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1)); 1388 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in); 1389 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1390 l_ptr->unacked_window = 0; 1391 buf_discard(buf); 1392 l_ptr->proto_msg_queue = NULL; 1393 return 0; 1394 } else { 1395 l_ptr->stats.bearer_congs++; 1396 return PUSH_FAILED; 1397 } 1398 } 1399 1400 /* Send one deferred data message, if send window not full: */ 1401 1402 buf = l_ptr->next_out; 1403 if (buf) { 1404 struct tipc_msg *msg = buf_msg(buf); 1405 u32 next = msg_seqno(msg); 1406 u32 first = msg_seqno(buf_msg(l_ptr->first_out)); 1407 1408 if (mod(next - first) < l_ptr->queue_limit[0]) { 1409 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); 1410 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 1411 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1412 if (msg_user(msg) == MSG_BUNDLER) 1413 msg_set_type(msg, CLOSED_MSG); 1414 l_ptr->next_out = buf->next; 1415 return 0; 1416 } else { 1417 l_ptr->stats.bearer_congs++; 1418 return PUSH_FAILED; 1419 } 1420 } 1421 } 1422 return PUSH_FINISHED; 1423 } 1424 1425 /* 1426 * push_queue(): push out the unsent messages of a link where 1427 * congestion has abated. Node is locked 1428 */ 1429 void tipc_link_push_queue(struct link *l_ptr) 1430 { 1431 u32 res; 1432 1433 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) 1434 return; 1435 1436 do { 1437 res = tipc_link_push_packet(l_ptr); 1438 } while (!res); 1439 1440 if (res == PUSH_FAILED) 1441 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 1442 } 1443 1444 static void link_reset_all(unsigned long addr) 1445 { 1446 struct tipc_node *n_ptr; 1447 char addr_string[16]; 1448 u32 i; 1449 1450 read_lock_bh(&tipc_net_lock); 1451 n_ptr = tipc_node_find((u32)addr); 1452 if (!n_ptr) { 1453 read_unlock_bh(&tipc_net_lock); 1454 return; /* node no longer exists */ 1455 } 1456 1457 tipc_node_lock(n_ptr); 1458 1459 warn("Resetting all links to %s\n", 1460 tipc_addr_string_fill(addr_string, n_ptr->addr)); 1461 1462 for (i = 0; i < MAX_BEARERS; i++) { 1463 if (n_ptr->links[i]) { 1464 link_print(n_ptr->links[i], "Resetting link\n"); 1465 tipc_link_reset(n_ptr->links[i]); 1466 } 1467 } 1468 1469 tipc_node_unlock(n_ptr); 1470 read_unlock_bh(&tipc_net_lock); 1471 } 1472 1473 static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf) 1474 { 1475 struct tipc_msg *msg = buf_msg(buf); 1476 1477 warn("Retransmission failure on link <%s>\n", l_ptr->name); 1478 1479 if (l_ptr->addr) { 1480 1481 /* Handle failure on standard link */ 1482 1483 link_print(l_ptr, "Resetting link\n"); 1484 tipc_link_reset(l_ptr); 1485 1486 } else { 1487 1488 /* Handle failure on broadcast link */ 1489 1490 struct tipc_node *n_ptr; 1491 char addr_string[16]; 1492 1493 info("Msg seq number: %u, ", msg_seqno(msg)); 1494 info("Outstanding acks: %lu\n", 1495 (unsigned long) TIPC_SKB_CB(buf)->handle); 1496 1497 n_ptr = tipc_bclink_retransmit_to(); 1498 tipc_node_lock(n_ptr); 1499 1500 tipc_addr_string_fill(addr_string, n_ptr->addr); 1501 info("Multicast link info for %s\n", addr_string); 1502 info("Supported: %d, ", n_ptr->bclink.supported); 1503 info("Acked: %u\n", n_ptr->bclink.acked); 1504 info("Last in: %u, ", n_ptr->bclink.last_in); 1505 info("Gap after: %u, ", n_ptr->bclink.gap_after); 1506 info("Gap to: %u\n", n_ptr->bclink.gap_to); 1507 info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync); 1508 1509 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr); 1510 1511 tipc_node_unlock(n_ptr); 1512 1513 l_ptr->stale_count = 0; 1514 } 1515 } 1516 1517 void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf, 1518 u32 retransmits) 1519 { 1520 struct tipc_msg *msg; 1521 1522 if (!buf) 1523 return; 1524 1525 msg = buf_msg(buf); 1526 1527 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { 1528 if (l_ptr->retransm_queue_size == 0) { 1529 l_ptr->retransm_queue_head = msg_seqno(msg); 1530 l_ptr->retransm_queue_size = retransmits; 1531 } else { 1532 err("Unexpected retransmit on link %s (qsize=%d)\n", 1533 l_ptr->name, l_ptr->retransm_queue_size); 1534 } 1535 return; 1536 } else { 1537 /* Detect repeated retransmit failures on uncongested bearer */ 1538 1539 if (l_ptr->last_retransmitted == msg_seqno(msg)) { 1540 if (++l_ptr->stale_count > 100) { 1541 link_retransmit_failure(l_ptr, buf); 1542 return; 1543 } 1544 } else { 1545 l_ptr->last_retransmitted = msg_seqno(msg); 1546 l_ptr->stale_count = 1; 1547 } 1548 } 1549 1550 while (retransmits && (buf != l_ptr->next_out) && buf) { 1551 msg = buf_msg(buf); 1552 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); 1553 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 1554 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1555 buf = buf->next; 1556 retransmits--; 1557 l_ptr->stats.retransmitted++; 1558 } else { 1559 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 1560 l_ptr->stats.bearer_congs++; 1561 l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf)); 1562 l_ptr->retransm_queue_size = retransmits; 1563 return; 1564 } 1565 } 1566 1567 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0; 1568 } 1569 1570 /** 1571 * link_insert_deferred_queue - insert deferred messages back into receive chain 1572 */ 1573 1574 static struct sk_buff *link_insert_deferred_queue(struct link *l_ptr, 1575 struct sk_buff *buf) 1576 { 1577 u32 seq_no; 1578 1579 if (l_ptr->oldest_deferred_in == NULL) 1580 return buf; 1581 1582 seq_no = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); 1583 if (seq_no == mod(l_ptr->next_in_no)) { 1584 l_ptr->newest_deferred_in->next = buf; 1585 buf = l_ptr->oldest_deferred_in; 1586 l_ptr->oldest_deferred_in = NULL; 1587 l_ptr->deferred_inqueue_sz = 0; 1588 } 1589 return buf; 1590 } 1591 1592 /** 1593 * link_recv_buf_validate - validate basic format of received message 1594 * 1595 * This routine ensures a TIPC message has an acceptable header, and at least 1596 * as much data as the header indicates it should. The routine also ensures 1597 * that the entire message header is stored in the main fragment of the message 1598 * buffer, to simplify future access to message header fields. 1599 * 1600 * Note: Having extra info present in the message header or data areas is OK. 1601 * TIPC will ignore the excess, under the assumption that it is optional info 1602 * introduced by a later release of the protocol. 1603 */ 1604 1605 static int link_recv_buf_validate(struct sk_buff *buf) 1606 { 1607 static u32 min_data_hdr_size[8] = { 1608 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE, 1609 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE 1610 }; 1611 1612 struct tipc_msg *msg; 1613 u32 tipc_hdr[2]; 1614 u32 size; 1615 u32 hdr_size; 1616 u32 min_hdr_size; 1617 1618 if (unlikely(buf->len < MIN_H_SIZE)) 1619 return 0; 1620 1621 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr); 1622 if (msg == NULL) 1623 return 0; 1624 1625 if (unlikely(msg_version(msg) != TIPC_VERSION)) 1626 return 0; 1627 1628 size = msg_size(msg); 1629 hdr_size = msg_hdr_sz(msg); 1630 min_hdr_size = msg_isdata(msg) ? 1631 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE; 1632 1633 if (unlikely((hdr_size < min_hdr_size) || 1634 (size < hdr_size) || 1635 (buf->len < size) || 1636 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE))) 1637 return 0; 1638 1639 return pskb_may_pull(buf, hdr_size); 1640 } 1641 1642 /** 1643 * tipc_recv_msg - process TIPC messages arriving from off-node 1644 * @head: pointer to message buffer chain 1645 * @tb_ptr: pointer to bearer message arrived on 1646 * 1647 * Invoked with no locks held. Bearer pointer must point to a valid bearer 1648 * structure (i.e. cannot be NULL), but bearer can be inactive. 1649 */ 1650 1651 void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr) 1652 { 1653 read_lock_bh(&tipc_net_lock); 1654 while (head) { 1655 struct tipc_node *n_ptr; 1656 struct link *l_ptr; 1657 struct sk_buff *crs; 1658 struct sk_buff *buf = head; 1659 struct tipc_msg *msg; 1660 u32 seq_no; 1661 u32 ackd; 1662 u32 released = 0; 1663 int type; 1664 1665 head = head->next; 1666 1667 /* Ensure bearer is still enabled */ 1668 1669 if (unlikely(!b_ptr->active)) 1670 goto cont; 1671 1672 /* Ensure message is well-formed */ 1673 1674 if (unlikely(!link_recv_buf_validate(buf))) 1675 goto cont; 1676 1677 /* Ensure message data is a single contiguous unit */ 1678 1679 if (unlikely(buf_linearize(buf))) 1680 goto cont; 1681 1682 /* Handle arrival of a non-unicast link message */ 1683 1684 msg = buf_msg(buf); 1685 1686 if (unlikely(msg_non_seq(msg))) { 1687 if (msg_user(msg) == LINK_CONFIG) 1688 tipc_disc_recv_msg(buf, b_ptr); 1689 else 1690 tipc_bclink_recv_pkt(buf); 1691 continue; 1692 } 1693 1694 /* Discard unicast link messages destined for another node */ 1695 1696 if (unlikely(!msg_short(msg) && 1697 (msg_destnode(msg) != tipc_own_addr))) 1698 goto cont; 1699 1700 /* Locate neighboring node that sent message */ 1701 1702 n_ptr = tipc_node_find(msg_prevnode(msg)); 1703 if (unlikely(!n_ptr)) 1704 goto cont; 1705 tipc_node_lock(n_ptr); 1706 1707 /* Locate unicast link endpoint that should handle message */ 1708 1709 l_ptr = n_ptr->links[b_ptr->identity]; 1710 if (unlikely(!l_ptr)) { 1711 tipc_node_unlock(n_ptr); 1712 goto cont; 1713 } 1714 1715 /* Verify that communication with node is currently allowed */ 1716 1717 if ((n_ptr->block_setup & WAIT_PEER_DOWN) && 1718 msg_user(msg) == LINK_PROTOCOL && 1719 (msg_type(msg) == RESET_MSG || 1720 msg_type(msg) == ACTIVATE_MSG) && 1721 !msg_redundant_link(msg)) 1722 n_ptr->block_setup &= ~WAIT_PEER_DOWN; 1723 1724 if (n_ptr->block_setup) { 1725 tipc_node_unlock(n_ptr); 1726 goto cont; 1727 } 1728 1729 /* Validate message sequence number info */ 1730 1731 seq_no = msg_seqno(msg); 1732 ackd = msg_ack(msg); 1733 1734 /* Release acked messages */ 1735 1736 if (less(n_ptr->bclink.acked, msg_bcast_ack(msg))) { 1737 if (tipc_node_is_up(n_ptr) && n_ptr->bclink.supported) 1738 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg)); 1739 } 1740 1741 crs = l_ptr->first_out; 1742 while ((crs != l_ptr->next_out) && 1743 less_eq(msg_seqno(buf_msg(crs)), ackd)) { 1744 struct sk_buff *next = crs->next; 1745 1746 buf_discard(crs); 1747 crs = next; 1748 released++; 1749 } 1750 if (released) { 1751 l_ptr->first_out = crs; 1752 l_ptr->out_queue_size -= released; 1753 } 1754 1755 /* Try sending any messages link endpoint has pending */ 1756 1757 if (unlikely(l_ptr->next_out)) 1758 tipc_link_push_queue(l_ptr); 1759 if (unlikely(!list_empty(&l_ptr->waiting_ports))) 1760 tipc_link_wakeup_ports(l_ptr, 0); 1761 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) { 1762 l_ptr->stats.sent_acks++; 1763 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); 1764 } 1765 1766 /* Now (finally!) process the incoming message */ 1767 1768 protocol_check: 1769 if (likely(link_working_working(l_ptr))) { 1770 if (likely(seq_no == mod(l_ptr->next_in_no))) { 1771 l_ptr->next_in_no++; 1772 if (unlikely(l_ptr->oldest_deferred_in)) 1773 head = link_insert_deferred_queue(l_ptr, 1774 head); 1775 if (likely(msg_is_dest(msg, tipc_own_addr))) { 1776 deliver: 1777 if (likely(msg_isdata(msg))) { 1778 tipc_node_unlock(n_ptr); 1779 tipc_port_recv_msg(buf); 1780 continue; 1781 } 1782 switch (msg_user(msg)) { 1783 case MSG_BUNDLER: 1784 l_ptr->stats.recv_bundles++; 1785 l_ptr->stats.recv_bundled += 1786 msg_msgcnt(msg); 1787 tipc_node_unlock(n_ptr); 1788 tipc_link_recv_bundle(buf); 1789 continue; 1790 case NAME_DISTRIBUTOR: 1791 tipc_node_unlock(n_ptr); 1792 tipc_named_recv(buf); 1793 continue; 1794 case CONN_MANAGER: 1795 tipc_node_unlock(n_ptr); 1796 tipc_port_recv_proto_msg(buf); 1797 continue; 1798 case MSG_FRAGMENTER: 1799 l_ptr->stats.recv_fragments++; 1800 if (tipc_link_recv_fragment(&l_ptr->defragm_buf, 1801 &buf, &msg)) { 1802 l_ptr->stats.recv_fragmented++; 1803 goto deliver; 1804 } 1805 break; 1806 case CHANGEOVER_PROTOCOL: 1807 type = msg_type(msg); 1808 if (link_recv_changeover_msg(&l_ptr, &buf)) { 1809 msg = buf_msg(buf); 1810 seq_no = msg_seqno(msg); 1811 if (type == ORIGINAL_MSG) 1812 goto deliver; 1813 goto protocol_check; 1814 } 1815 break; 1816 default: 1817 buf_discard(buf); 1818 buf = NULL; 1819 break; 1820 } 1821 } 1822 tipc_node_unlock(n_ptr); 1823 tipc_net_route_msg(buf); 1824 continue; 1825 } 1826 link_handle_out_of_seq_msg(l_ptr, buf); 1827 head = link_insert_deferred_queue(l_ptr, head); 1828 tipc_node_unlock(n_ptr); 1829 continue; 1830 } 1831 1832 if (msg_user(msg) == LINK_PROTOCOL) { 1833 link_recv_proto_msg(l_ptr, buf); 1834 head = link_insert_deferred_queue(l_ptr, head); 1835 tipc_node_unlock(n_ptr); 1836 continue; 1837 } 1838 link_state_event(l_ptr, TRAFFIC_MSG_EVT); 1839 1840 if (link_working_working(l_ptr)) { 1841 /* Re-insert in front of queue */ 1842 buf->next = head; 1843 head = buf; 1844 tipc_node_unlock(n_ptr); 1845 continue; 1846 } 1847 tipc_node_unlock(n_ptr); 1848 cont: 1849 buf_discard(buf); 1850 } 1851 read_unlock_bh(&tipc_net_lock); 1852 } 1853 1854 /* 1855 * link_defer_buf(): Sort a received out-of-sequence packet 1856 * into the deferred reception queue. 1857 * Returns the increase of the queue length,i.e. 0 or 1 1858 */ 1859 1860 u32 tipc_link_defer_pkt(struct sk_buff **head, 1861 struct sk_buff **tail, 1862 struct sk_buff *buf) 1863 { 1864 struct sk_buff *prev = NULL; 1865 struct sk_buff *crs = *head; 1866 u32 seq_no = msg_seqno(buf_msg(buf)); 1867 1868 buf->next = NULL; 1869 1870 /* Empty queue ? */ 1871 if (*head == NULL) { 1872 *head = *tail = buf; 1873 return 1; 1874 } 1875 1876 /* Last ? */ 1877 if (less(msg_seqno(buf_msg(*tail)), seq_no)) { 1878 (*tail)->next = buf; 1879 *tail = buf; 1880 return 1; 1881 } 1882 1883 /* Scan through queue and sort it in */ 1884 do { 1885 struct tipc_msg *msg = buf_msg(crs); 1886 1887 if (less(seq_no, msg_seqno(msg))) { 1888 buf->next = crs; 1889 if (prev) 1890 prev->next = buf; 1891 else 1892 *head = buf; 1893 return 1; 1894 } 1895 if (seq_no == msg_seqno(msg)) 1896 break; 1897 prev = crs; 1898 crs = crs->next; 1899 } while (crs); 1900 1901 /* Message is a duplicate of an existing message */ 1902 1903 buf_discard(buf); 1904 return 0; 1905 } 1906 1907 /** 1908 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet 1909 */ 1910 1911 static void link_handle_out_of_seq_msg(struct link *l_ptr, 1912 struct sk_buff *buf) 1913 { 1914 u32 seq_no = msg_seqno(buf_msg(buf)); 1915 1916 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) { 1917 link_recv_proto_msg(l_ptr, buf); 1918 return; 1919 } 1920 1921 /* Record OOS packet arrival (force mismatch on next timeout) */ 1922 1923 l_ptr->checkpoint--; 1924 1925 /* 1926 * Discard packet if a duplicate; otherwise add it to deferred queue 1927 * and notify peer of gap as per protocol specification 1928 */ 1929 1930 if (less(seq_no, mod(l_ptr->next_in_no))) { 1931 l_ptr->stats.duplicates++; 1932 buf_discard(buf); 1933 return; 1934 } 1935 1936 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in, 1937 &l_ptr->newest_deferred_in, buf)) { 1938 l_ptr->deferred_inqueue_sz++; 1939 l_ptr->stats.deferred_recv++; 1940 if ((l_ptr->deferred_inqueue_sz % 16) == 1) 1941 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); 1942 } else 1943 l_ptr->stats.duplicates++; 1944 } 1945 1946 /* 1947 * Send protocol message to the other endpoint. 1948 */ 1949 void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int probe_msg, 1950 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu) 1951 { 1952 struct sk_buff *buf = NULL; 1953 struct tipc_msg *msg = l_ptr->pmsg; 1954 u32 msg_size = sizeof(l_ptr->proto_msg); 1955 int r_flag; 1956 1957 if (link_blocked(l_ptr)) 1958 return; 1959 1960 /* Abort non-RESET send if communication with node is prohibited */ 1961 1962 if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG)) 1963 return; 1964 1965 msg_set_type(msg, msg_typ); 1966 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane); 1967 msg_set_bcast_ack(msg, mod(l_ptr->owner->bclink.last_in)); 1968 msg_set_last_bcast(msg, tipc_bclink_get_last_sent()); 1969 1970 if (msg_typ == STATE_MSG) { 1971 u32 next_sent = mod(l_ptr->next_out_no); 1972 1973 if (!tipc_link_is_up(l_ptr)) 1974 return; 1975 if (l_ptr->next_out) 1976 next_sent = msg_seqno(buf_msg(l_ptr->next_out)); 1977 msg_set_next_sent(msg, next_sent); 1978 if (l_ptr->oldest_deferred_in) { 1979 u32 rec = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); 1980 gap = mod(rec - mod(l_ptr->next_in_no)); 1981 } 1982 msg_set_seq_gap(msg, gap); 1983 if (gap) 1984 l_ptr->stats.sent_nacks++; 1985 msg_set_link_tolerance(msg, tolerance); 1986 msg_set_linkprio(msg, priority); 1987 msg_set_max_pkt(msg, ack_mtu); 1988 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); 1989 msg_set_probe(msg, probe_msg != 0); 1990 if (probe_msg) { 1991 u32 mtu = l_ptr->max_pkt; 1992 1993 if ((mtu < l_ptr->max_pkt_target) && 1994 link_working_working(l_ptr) && 1995 l_ptr->fsm_msg_cnt) { 1996 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3; 1997 if (l_ptr->max_pkt_probes == 10) { 1998 l_ptr->max_pkt_target = (msg_size - 4); 1999 l_ptr->max_pkt_probes = 0; 2000 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3; 2001 } 2002 l_ptr->max_pkt_probes++; 2003 } 2004 2005 l_ptr->stats.sent_probes++; 2006 } 2007 l_ptr->stats.sent_states++; 2008 } else { /* RESET_MSG or ACTIVATE_MSG */ 2009 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1)); 2010 msg_set_seq_gap(msg, 0); 2011 msg_set_next_sent(msg, 1); 2012 msg_set_probe(msg, 0); 2013 msg_set_link_tolerance(msg, l_ptr->tolerance); 2014 msg_set_linkprio(msg, l_ptr->priority); 2015 msg_set_max_pkt(msg, l_ptr->max_pkt_target); 2016 } 2017 2018 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr)); 2019 msg_set_redundant_link(msg, r_flag); 2020 msg_set_linkprio(msg, l_ptr->priority); 2021 2022 /* Ensure sequence number will not fit : */ 2023 2024 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2))); 2025 2026 /* Congestion? */ 2027 2028 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { 2029 if (!l_ptr->proto_msg_queue) { 2030 l_ptr->proto_msg_queue = 2031 tipc_buf_acquire(sizeof(l_ptr->proto_msg)); 2032 } 2033 buf = l_ptr->proto_msg_queue; 2034 if (!buf) 2035 return; 2036 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); 2037 return; 2038 } 2039 2040 /* Message can be sent */ 2041 2042 buf = tipc_buf_acquire(msg_size); 2043 if (!buf) 2044 return; 2045 2046 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); 2047 msg_set_size(buf_msg(buf), msg_size); 2048 2049 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 2050 l_ptr->unacked_window = 0; 2051 buf_discard(buf); 2052 return; 2053 } 2054 2055 /* New congestion */ 2056 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 2057 l_ptr->proto_msg_queue = buf; 2058 l_ptr->stats.bearer_congs++; 2059 } 2060 2061 /* 2062 * Receive protocol message : 2063 * Note that network plane id propagates through the network, and may 2064 * change at any time. The node with lowest address rules 2065 */ 2066 2067 static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf) 2068 { 2069 u32 rec_gap = 0; 2070 u32 max_pkt_info; 2071 u32 max_pkt_ack; 2072 u32 msg_tol; 2073 struct tipc_msg *msg = buf_msg(buf); 2074 2075 if (link_blocked(l_ptr)) 2076 goto exit; 2077 2078 /* record unnumbered packet arrival (force mismatch on next timeout) */ 2079 2080 l_ptr->checkpoint--; 2081 2082 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg)) 2083 if (tipc_own_addr > msg_prevnode(msg)) 2084 l_ptr->b_ptr->net_plane = msg_net_plane(msg); 2085 2086 l_ptr->owner->permit_changeover = msg_redundant_link(msg); 2087 2088 switch (msg_type(msg)) { 2089 2090 case RESET_MSG: 2091 if (!link_working_unknown(l_ptr) && 2092 (l_ptr->peer_session != INVALID_SESSION)) { 2093 if (less_eq(msg_session(msg), l_ptr->peer_session)) 2094 break; /* duplicate or old reset: ignore */ 2095 } 2096 2097 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) || 2098 link_working_unknown(l_ptr))) { 2099 /* 2100 * peer has lost contact -- don't allow peer's links 2101 * to reactivate before we recognize loss & clean up 2102 */ 2103 l_ptr->owner->block_setup = WAIT_NODE_DOWN; 2104 } 2105 2106 /* fall thru' */ 2107 case ACTIVATE_MSG: 2108 /* Update link settings according other endpoint's values */ 2109 2110 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg)); 2111 2112 msg_tol = msg_link_tolerance(msg); 2113 if (msg_tol > l_ptr->tolerance) 2114 link_set_supervision_props(l_ptr, msg_tol); 2115 2116 if (msg_linkprio(msg) > l_ptr->priority) 2117 l_ptr->priority = msg_linkprio(msg); 2118 2119 max_pkt_info = msg_max_pkt(msg); 2120 if (max_pkt_info) { 2121 if (max_pkt_info < l_ptr->max_pkt_target) 2122 l_ptr->max_pkt_target = max_pkt_info; 2123 if (l_ptr->max_pkt > l_ptr->max_pkt_target) 2124 l_ptr->max_pkt = l_ptr->max_pkt_target; 2125 } else { 2126 l_ptr->max_pkt = l_ptr->max_pkt_target; 2127 } 2128 l_ptr->owner->bclink.supported = (max_pkt_info != 0); 2129 2130 link_state_event(l_ptr, msg_type(msg)); 2131 2132 l_ptr->peer_session = msg_session(msg); 2133 l_ptr->peer_bearer_id = msg_bearer_id(msg); 2134 2135 /* Synchronize broadcast sequence numbers */ 2136 if (!tipc_node_redundant_links(l_ptr->owner)) 2137 l_ptr->owner->bclink.last_in = mod(msg_last_bcast(msg)); 2138 break; 2139 case STATE_MSG: 2140 2141 msg_tol = msg_link_tolerance(msg); 2142 if (msg_tol) 2143 link_set_supervision_props(l_ptr, msg_tol); 2144 2145 if (msg_linkprio(msg) && 2146 (msg_linkprio(msg) != l_ptr->priority)) { 2147 warn("Resetting link <%s>, priority change %u->%u\n", 2148 l_ptr->name, l_ptr->priority, msg_linkprio(msg)); 2149 l_ptr->priority = msg_linkprio(msg); 2150 tipc_link_reset(l_ptr); /* Enforce change to take effect */ 2151 break; 2152 } 2153 link_state_event(l_ptr, TRAFFIC_MSG_EVT); 2154 l_ptr->stats.recv_states++; 2155 if (link_reset_unknown(l_ptr)) 2156 break; 2157 2158 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) { 2159 rec_gap = mod(msg_next_sent(msg) - 2160 mod(l_ptr->next_in_no)); 2161 } 2162 2163 max_pkt_ack = msg_max_pkt(msg); 2164 if (max_pkt_ack > l_ptr->max_pkt) { 2165 l_ptr->max_pkt = max_pkt_ack; 2166 l_ptr->max_pkt_probes = 0; 2167 } 2168 2169 max_pkt_ack = 0; 2170 if (msg_probe(msg)) { 2171 l_ptr->stats.recv_probes++; 2172 if (msg_size(msg) > sizeof(l_ptr->proto_msg)) 2173 max_pkt_ack = msg_size(msg); 2174 } 2175 2176 /* Protocol message before retransmits, reduce loss risk */ 2177 2178 tipc_bclink_check_gap(l_ptr->owner, msg_last_bcast(msg)); 2179 2180 if (rec_gap || (msg_probe(msg))) { 2181 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 2182 0, rec_gap, 0, 0, max_pkt_ack); 2183 } 2184 if (msg_seq_gap(msg)) { 2185 l_ptr->stats.recv_nacks++; 2186 tipc_link_retransmit(l_ptr, l_ptr->first_out, 2187 msg_seq_gap(msg)); 2188 } 2189 break; 2190 } 2191 exit: 2192 buf_discard(buf); 2193 } 2194 2195 2196 /* 2197 * tipc_link_tunnel(): Send one message via a link belonging to 2198 * another bearer. Owner node is locked. 2199 */ 2200 static void tipc_link_tunnel(struct link *l_ptr, 2201 struct tipc_msg *tunnel_hdr, 2202 struct tipc_msg *msg, 2203 u32 selector) 2204 { 2205 struct link *tunnel; 2206 struct sk_buff *buf; 2207 u32 length = msg_size(msg); 2208 2209 tunnel = l_ptr->owner->active_links[selector & 1]; 2210 if (!tipc_link_is_up(tunnel)) { 2211 warn("Link changeover error, " 2212 "tunnel link no longer available\n"); 2213 return; 2214 } 2215 msg_set_size(tunnel_hdr, length + INT_H_SIZE); 2216 buf = tipc_buf_acquire(length + INT_H_SIZE); 2217 if (!buf) { 2218 warn("Link changeover error, " 2219 "unable to send tunnel msg\n"); 2220 return; 2221 } 2222 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE); 2223 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length); 2224 tipc_link_send_buf(tunnel, buf); 2225 } 2226 2227 2228 2229 /* 2230 * changeover(): Send whole message queue via the remaining link 2231 * Owner node is locked. 2232 */ 2233 2234 void tipc_link_changeover(struct link *l_ptr) 2235 { 2236 u32 msgcount = l_ptr->out_queue_size; 2237 struct sk_buff *crs = l_ptr->first_out; 2238 struct link *tunnel = l_ptr->owner->active_links[0]; 2239 struct tipc_msg tunnel_hdr; 2240 int split_bundles; 2241 2242 if (!tunnel) 2243 return; 2244 2245 if (!l_ptr->owner->permit_changeover) { 2246 warn("Link changeover error, " 2247 "peer did not permit changeover\n"); 2248 return; 2249 } 2250 2251 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL, 2252 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr); 2253 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id); 2254 msg_set_msgcnt(&tunnel_hdr, msgcount); 2255 2256 if (!l_ptr->first_out) { 2257 struct sk_buff *buf; 2258 2259 buf = tipc_buf_acquire(INT_H_SIZE); 2260 if (buf) { 2261 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE); 2262 msg_set_size(&tunnel_hdr, INT_H_SIZE); 2263 tipc_link_send_buf(tunnel, buf); 2264 } else { 2265 warn("Link changeover error, " 2266 "unable to send changeover msg\n"); 2267 } 2268 return; 2269 } 2270 2271 split_bundles = (l_ptr->owner->active_links[0] != 2272 l_ptr->owner->active_links[1]); 2273 2274 while (crs) { 2275 struct tipc_msg *msg = buf_msg(crs); 2276 2277 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) { 2278 struct tipc_msg *m = msg_get_wrapped(msg); 2279 unchar *pos = (unchar *)m; 2280 2281 msgcount = msg_msgcnt(msg); 2282 while (msgcount--) { 2283 msg_set_seqno(m, msg_seqno(msg)); 2284 tipc_link_tunnel(l_ptr, &tunnel_hdr, m, 2285 msg_link_selector(m)); 2286 pos += align(msg_size(m)); 2287 m = (struct tipc_msg *)pos; 2288 } 2289 } else { 2290 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg, 2291 msg_link_selector(msg)); 2292 } 2293 crs = crs->next; 2294 } 2295 } 2296 2297 void tipc_link_send_duplicate(struct link *l_ptr, struct link *tunnel) 2298 { 2299 struct sk_buff *iter; 2300 struct tipc_msg tunnel_hdr; 2301 2302 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL, 2303 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr); 2304 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size); 2305 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id); 2306 iter = l_ptr->first_out; 2307 while (iter) { 2308 struct sk_buff *outbuf; 2309 struct tipc_msg *msg = buf_msg(iter); 2310 u32 length = msg_size(msg); 2311 2312 if (msg_user(msg) == MSG_BUNDLER) 2313 msg_set_type(msg, CLOSED_MSG); 2314 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */ 2315 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 2316 msg_set_size(&tunnel_hdr, length + INT_H_SIZE); 2317 outbuf = tipc_buf_acquire(length + INT_H_SIZE); 2318 if (outbuf == NULL) { 2319 warn("Link changeover error, " 2320 "unable to send duplicate msg\n"); 2321 return; 2322 } 2323 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE); 2324 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data, 2325 length); 2326 tipc_link_send_buf(tunnel, outbuf); 2327 if (!tipc_link_is_up(l_ptr)) 2328 return; 2329 iter = iter->next; 2330 } 2331 } 2332 2333 2334 2335 /** 2336 * buf_extract - extracts embedded TIPC message from another message 2337 * @skb: encapsulating message buffer 2338 * @from_pos: offset to extract from 2339 * 2340 * Returns a new message buffer containing an embedded message. The 2341 * encapsulating message itself is left unchanged. 2342 */ 2343 2344 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos) 2345 { 2346 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos); 2347 u32 size = msg_size(msg); 2348 struct sk_buff *eb; 2349 2350 eb = tipc_buf_acquire(size); 2351 if (eb) 2352 skb_copy_to_linear_data(eb, msg, size); 2353 return eb; 2354 } 2355 2356 /* 2357 * link_recv_changeover_msg(): Receive tunneled packet sent 2358 * via other link. Node is locked. Return extracted buffer. 2359 */ 2360 2361 static int link_recv_changeover_msg(struct link **l_ptr, 2362 struct sk_buff **buf) 2363 { 2364 struct sk_buff *tunnel_buf = *buf; 2365 struct link *dest_link; 2366 struct tipc_msg *msg; 2367 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf); 2368 u32 msg_typ = msg_type(tunnel_msg); 2369 u32 msg_count = msg_msgcnt(tunnel_msg); 2370 2371 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)]; 2372 if (!dest_link) 2373 goto exit; 2374 if (dest_link == *l_ptr) { 2375 err("Unexpected changeover message on link <%s>\n", 2376 (*l_ptr)->name); 2377 goto exit; 2378 } 2379 *l_ptr = dest_link; 2380 msg = msg_get_wrapped(tunnel_msg); 2381 2382 if (msg_typ == DUPLICATE_MSG) { 2383 if (less(msg_seqno(msg), mod(dest_link->next_in_no))) 2384 goto exit; 2385 *buf = buf_extract(tunnel_buf, INT_H_SIZE); 2386 if (*buf == NULL) { 2387 warn("Link changeover error, duplicate msg dropped\n"); 2388 goto exit; 2389 } 2390 buf_discard(tunnel_buf); 2391 return 1; 2392 } 2393 2394 /* First original message ?: */ 2395 2396 if (tipc_link_is_up(dest_link)) { 2397 info("Resetting link <%s>, changeover initiated by peer\n", 2398 dest_link->name); 2399 tipc_link_reset(dest_link); 2400 dest_link->exp_msg_count = msg_count; 2401 if (!msg_count) 2402 goto exit; 2403 } else if (dest_link->exp_msg_count == START_CHANGEOVER) { 2404 dest_link->exp_msg_count = msg_count; 2405 if (!msg_count) 2406 goto exit; 2407 } 2408 2409 /* Receive original message */ 2410 2411 if (dest_link->exp_msg_count == 0) { 2412 warn("Link switchover error, " 2413 "got too many tunnelled messages\n"); 2414 goto exit; 2415 } 2416 dest_link->exp_msg_count--; 2417 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) { 2418 goto exit; 2419 } else { 2420 *buf = buf_extract(tunnel_buf, INT_H_SIZE); 2421 if (*buf != NULL) { 2422 buf_discard(tunnel_buf); 2423 return 1; 2424 } else { 2425 warn("Link changeover error, original msg dropped\n"); 2426 } 2427 } 2428 exit: 2429 *buf = NULL; 2430 buf_discard(tunnel_buf); 2431 return 0; 2432 } 2433 2434 /* 2435 * Bundler functionality: 2436 */ 2437 void tipc_link_recv_bundle(struct sk_buff *buf) 2438 { 2439 u32 msgcount = msg_msgcnt(buf_msg(buf)); 2440 u32 pos = INT_H_SIZE; 2441 struct sk_buff *obuf; 2442 2443 while (msgcount--) { 2444 obuf = buf_extract(buf, pos); 2445 if (obuf == NULL) { 2446 warn("Link unable to unbundle message(s)\n"); 2447 break; 2448 } 2449 pos += align(msg_size(buf_msg(obuf))); 2450 tipc_net_route_msg(obuf); 2451 } 2452 buf_discard(buf); 2453 } 2454 2455 /* 2456 * Fragmentation/defragmentation: 2457 */ 2458 2459 2460 /* 2461 * link_send_long_buf: Entry for buffers needing fragmentation. 2462 * The buffer is complete, inclusive total message length. 2463 * Returns user data length. 2464 */ 2465 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf) 2466 { 2467 struct sk_buff *buf_chain = NULL; 2468 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain; 2469 struct tipc_msg *inmsg = buf_msg(buf); 2470 struct tipc_msg fragm_hdr; 2471 u32 insize = msg_size(inmsg); 2472 u32 dsz = msg_data_sz(inmsg); 2473 unchar *crs = buf->data; 2474 u32 rest = insize; 2475 u32 pack_sz = l_ptr->max_pkt; 2476 u32 fragm_sz = pack_sz - INT_H_SIZE; 2477 u32 fragm_no = 0; 2478 u32 destaddr; 2479 2480 if (msg_short(inmsg)) 2481 destaddr = l_ptr->addr; 2482 else 2483 destaddr = msg_destnode(inmsg); 2484 2485 /* Prepare reusable fragment header: */ 2486 2487 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT, 2488 INT_H_SIZE, destaddr); 2489 2490 /* Chop up message: */ 2491 2492 while (rest > 0) { 2493 struct sk_buff *fragm; 2494 2495 if (rest <= fragm_sz) { 2496 fragm_sz = rest; 2497 msg_set_type(&fragm_hdr, LAST_FRAGMENT); 2498 } 2499 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE); 2500 if (fragm == NULL) { 2501 buf_discard(buf); 2502 while (buf_chain) { 2503 buf = buf_chain; 2504 buf_chain = buf_chain->next; 2505 buf_discard(buf); 2506 } 2507 return -ENOMEM; 2508 } 2509 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE); 2510 fragm_no++; 2511 msg_set_fragm_no(&fragm_hdr, fragm_no); 2512 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE); 2513 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs, 2514 fragm_sz); 2515 buf_chain_tail->next = fragm; 2516 buf_chain_tail = fragm; 2517 2518 rest -= fragm_sz; 2519 crs += fragm_sz; 2520 msg_set_type(&fragm_hdr, FRAGMENT); 2521 } 2522 buf_discard(buf); 2523 2524 /* Append chain of fragments to send queue & send them */ 2525 2526 l_ptr->long_msg_seq_no++; 2527 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no); 2528 l_ptr->stats.sent_fragments += fragm_no; 2529 l_ptr->stats.sent_fragmented++; 2530 tipc_link_push_queue(l_ptr); 2531 2532 return dsz; 2533 } 2534 2535 /* 2536 * A pending message being re-assembled must store certain values 2537 * to handle subsequent fragments correctly. The following functions 2538 * help storing these values in unused, available fields in the 2539 * pending message. This makes dynamic memory allocation unnecessary. 2540 */ 2541 2542 static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno) 2543 { 2544 msg_set_seqno(buf_msg(buf), seqno); 2545 } 2546 2547 static u32 get_fragm_size(struct sk_buff *buf) 2548 { 2549 return msg_ack(buf_msg(buf)); 2550 } 2551 2552 static void set_fragm_size(struct sk_buff *buf, u32 sz) 2553 { 2554 msg_set_ack(buf_msg(buf), sz); 2555 } 2556 2557 static u32 get_expected_frags(struct sk_buff *buf) 2558 { 2559 return msg_bcast_ack(buf_msg(buf)); 2560 } 2561 2562 static void set_expected_frags(struct sk_buff *buf, u32 exp) 2563 { 2564 msg_set_bcast_ack(buf_msg(buf), exp); 2565 } 2566 2567 static u32 get_timer_cnt(struct sk_buff *buf) 2568 { 2569 return msg_reroute_cnt(buf_msg(buf)); 2570 } 2571 2572 static void incr_timer_cnt(struct sk_buff *buf) 2573 { 2574 msg_incr_reroute_cnt(buf_msg(buf)); 2575 } 2576 2577 /* 2578 * tipc_link_recv_fragment(): Called with node lock on. Returns 2579 * the reassembled buffer if message is complete. 2580 */ 2581 int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb, 2582 struct tipc_msg **m) 2583 { 2584 struct sk_buff *prev = NULL; 2585 struct sk_buff *fbuf = *fb; 2586 struct tipc_msg *fragm = buf_msg(fbuf); 2587 struct sk_buff *pbuf = *pending; 2588 u32 long_msg_seq_no = msg_long_msgno(fragm); 2589 2590 *fb = NULL; 2591 2592 /* Is there an incomplete message waiting for this fragment? */ 2593 2594 while (pbuf && ((msg_seqno(buf_msg(pbuf)) != long_msg_seq_no) || 2595 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) { 2596 prev = pbuf; 2597 pbuf = pbuf->next; 2598 } 2599 2600 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) { 2601 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm); 2602 u32 msg_sz = msg_size(imsg); 2603 u32 fragm_sz = msg_data_sz(fragm); 2604 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz); 2605 u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE; 2606 if (msg_type(imsg) == TIPC_MCAST_MSG) 2607 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE; 2608 if (msg_size(imsg) > max) { 2609 buf_discard(fbuf); 2610 return 0; 2611 } 2612 pbuf = tipc_buf_acquire(msg_size(imsg)); 2613 if (pbuf != NULL) { 2614 pbuf->next = *pending; 2615 *pending = pbuf; 2616 skb_copy_to_linear_data(pbuf, imsg, 2617 msg_data_sz(fragm)); 2618 /* Prepare buffer for subsequent fragments. */ 2619 2620 set_long_msg_seqno(pbuf, long_msg_seq_no); 2621 set_fragm_size(pbuf, fragm_sz); 2622 set_expected_frags(pbuf, exp_fragm_cnt - 1); 2623 } else { 2624 warn("Link unable to reassemble fragmented message\n"); 2625 } 2626 buf_discard(fbuf); 2627 return 0; 2628 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) { 2629 u32 dsz = msg_data_sz(fragm); 2630 u32 fsz = get_fragm_size(pbuf); 2631 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz); 2632 u32 exp_frags = get_expected_frags(pbuf) - 1; 2633 skb_copy_to_linear_data_offset(pbuf, crs, 2634 msg_data(fragm), dsz); 2635 buf_discard(fbuf); 2636 2637 /* Is message complete? */ 2638 2639 if (exp_frags == 0) { 2640 if (prev) 2641 prev->next = pbuf->next; 2642 else 2643 *pending = pbuf->next; 2644 msg_reset_reroute_cnt(buf_msg(pbuf)); 2645 *fb = pbuf; 2646 *m = buf_msg(pbuf); 2647 return 1; 2648 } 2649 set_expected_frags(pbuf, exp_frags); 2650 return 0; 2651 } 2652 buf_discard(fbuf); 2653 return 0; 2654 } 2655 2656 /** 2657 * link_check_defragm_bufs - flush stale incoming message fragments 2658 * @l_ptr: pointer to link 2659 */ 2660 2661 static void link_check_defragm_bufs(struct link *l_ptr) 2662 { 2663 struct sk_buff *prev = NULL; 2664 struct sk_buff *next = NULL; 2665 struct sk_buff *buf = l_ptr->defragm_buf; 2666 2667 if (!buf) 2668 return; 2669 if (!link_working_working(l_ptr)) 2670 return; 2671 while (buf) { 2672 u32 cnt = get_timer_cnt(buf); 2673 2674 next = buf->next; 2675 if (cnt < 4) { 2676 incr_timer_cnt(buf); 2677 prev = buf; 2678 } else { 2679 if (prev) 2680 prev->next = buf->next; 2681 else 2682 l_ptr->defragm_buf = buf->next; 2683 buf_discard(buf); 2684 } 2685 buf = next; 2686 } 2687 } 2688 2689 2690 2691 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance) 2692 { 2693 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL)) 2694 return; 2695 2696 l_ptr->tolerance = tolerance; 2697 l_ptr->continuity_interval = 2698 ((tolerance / 4) > 500) ? 500 : tolerance / 4; 2699 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4); 2700 } 2701 2702 2703 void tipc_link_set_queue_limits(struct link *l_ptr, u32 window) 2704 { 2705 /* Data messages from this node, inclusive FIRST_FRAGM */ 2706 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window; 2707 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4; 2708 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5; 2709 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6; 2710 /* Transiting data messages,inclusive FIRST_FRAGM */ 2711 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300; 2712 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600; 2713 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900; 2714 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200; 2715 l_ptr->queue_limit[CONN_MANAGER] = 1200; 2716 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500; 2717 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000; 2718 /* FRAGMENT and LAST_FRAGMENT packets */ 2719 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000; 2720 } 2721 2722 /** 2723 * link_find_link - locate link by name 2724 * @name - ptr to link name string 2725 * @node - ptr to area to be filled with ptr to associated node 2726 * 2727 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted; 2728 * this also prevents link deletion. 2729 * 2730 * Returns pointer to link (or 0 if invalid link name). 2731 */ 2732 2733 static struct link *link_find_link(const char *name, struct tipc_node **node) 2734 { 2735 struct link_name link_name_parts; 2736 struct tipc_bearer *b_ptr; 2737 struct link *l_ptr; 2738 2739 if (!link_name_validate(name, &link_name_parts)) 2740 return NULL; 2741 2742 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local); 2743 if (!b_ptr) 2744 return NULL; 2745 2746 *node = tipc_node_find(link_name_parts.addr_peer); 2747 if (!*node) 2748 return NULL; 2749 2750 l_ptr = (*node)->links[b_ptr->identity]; 2751 if (!l_ptr || strcmp(l_ptr->name, name)) 2752 return NULL; 2753 2754 return l_ptr; 2755 } 2756 2757 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, 2758 u16 cmd) 2759 { 2760 struct tipc_link_config *args; 2761 u32 new_value; 2762 struct link *l_ptr; 2763 struct tipc_node *node; 2764 int res; 2765 2766 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG)) 2767 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 2768 2769 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area); 2770 new_value = ntohl(args->value); 2771 2772 if (!strcmp(args->name, tipc_bclink_name)) { 2773 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) && 2774 (tipc_bclink_set_queue_limits(new_value) == 0)) 2775 return tipc_cfg_reply_none(); 2776 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED 2777 " (cannot change setting on broadcast link)"); 2778 } 2779 2780 read_lock_bh(&tipc_net_lock); 2781 l_ptr = link_find_link(args->name, &node); 2782 if (!l_ptr) { 2783 read_unlock_bh(&tipc_net_lock); 2784 return tipc_cfg_reply_error_string("link not found"); 2785 } 2786 2787 tipc_node_lock(node); 2788 res = -EINVAL; 2789 switch (cmd) { 2790 case TIPC_CMD_SET_LINK_TOL: 2791 if ((new_value >= TIPC_MIN_LINK_TOL) && 2792 (new_value <= TIPC_MAX_LINK_TOL)) { 2793 link_set_supervision_props(l_ptr, new_value); 2794 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 2795 0, 0, new_value, 0, 0); 2796 res = 0; 2797 } 2798 break; 2799 case TIPC_CMD_SET_LINK_PRI: 2800 if ((new_value >= TIPC_MIN_LINK_PRI) && 2801 (new_value <= TIPC_MAX_LINK_PRI)) { 2802 l_ptr->priority = new_value; 2803 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 2804 0, 0, 0, new_value, 0); 2805 res = 0; 2806 } 2807 break; 2808 case TIPC_CMD_SET_LINK_WINDOW: 2809 if ((new_value >= TIPC_MIN_LINK_WIN) && 2810 (new_value <= TIPC_MAX_LINK_WIN)) { 2811 tipc_link_set_queue_limits(l_ptr, new_value); 2812 res = 0; 2813 } 2814 break; 2815 } 2816 tipc_node_unlock(node); 2817 2818 read_unlock_bh(&tipc_net_lock); 2819 if (res) 2820 return tipc_cfg_reply_error_string("cannot change link setting"); 2821 2822 return tipc_cfg_reply_none(); 2823 } 2824 2825 /** 2826 * link_reset_statistics - reset link statistics 2827 * @l_ptr: pointer to link 2828 */ 2829 2830 static void link_reset_statistics(struct link *l_ptr) 2831 { 2832 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats)); 2833 l_ptr->stats.sent_info = l_ptr->next_out_no; 2834 l_ptr->stats.recv_info = l_ptr->next_in_no; 2835 } 2836 2837 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space) 2838 { 2839 char *link_name; 2840 struct link *l_ptr; 2841 struct tipc_node *node; 2842 2843 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME)) 2844 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 2845 2846 link_name = (char *)TLV_DATA(req_tlv_area); 2847 if (!strcmp(link_name, tipc_bclink_name)) { 2848 if (tipc_bclink_reset_stats()) 2849 return tipc_cfg_reply_error_string("link not found"); 2850 return tipc_cfg_reply_none(); 2851 } 2852 2853 read_lock_bh(&tipc_net_lock); 2854 l_ptr = link_find_link(link_name, &node); 2855 if (!l_ptr) { 2856 read_unlock_bh(&tipc_net_lock); 2857 return tipc_cfg_reply_error_string("link not found"); 2858 } 2859 2860 tipc_node_lock(node); 2861 link_reset_statistics(l_ptr); 2862 tipc_node_unlock(node); 2863 read_unlock_bh(&tipc_net_lock); 2864 return tipc_cfg_reply_none(); 2865 } 2866 2867 /** 2868 * percent - convert count to a percentage of total (rounding up or down) 2869 */ 2870 2871 static u32 percent(u32 count, u32 total) 2872 { 2873 return (count * 100 + (total / 2)) / total; 2874 } 2875 2876 /** 2877 * tipc_link_stats - print link statistics 2878 * @name: link name 2879 * @buf: print buffer area 2880 * @buf_size: size of print buffer area 2881 * 2882 * Returns length of print buffer data string (or 0 if error) 2883 */ 2884 2885 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size) 2886 { 2887 struct print_buf pb; 2888 struct link *l_ptr; 2889 struct tipc_node *node; 2890 char *status; 2891 u32 profile_total = 0; 2892 2893 if (!strcmp(name, tipc_bclink_name)) 2894 return tipc_bclink_stats(buf, buf_size); 2895 2896 tipc_printbuf_init(&pb, buf, buf_size); 2897 2898 read_lock_bh(&tipc_net_lock); 2899 l_ptr = link_find_link(name, &node); 2900 if (!l_ptr) { 2901 read_unlock_bh(&tipc_net_lock); 2902 return 0; 2903 } 2904 tipc_node_lock(node); 2905 2906 if (tipc_link_is_active(l_ptr)) 2907 status = "ACTIVE"; 2908 else if (tipc_link_is_up(l_ptr)) 2909 status = "STANDBY"; 2910 else 2911 status = "DEFUNCT"; 2912 tipc_printf(&pb, "Link <%s>\n" 2913 " %s MTU:%u Priority:%u Tolerance:%u ms" 2914 " Window:%u packets\n", 2915 l_ptr->name, status, l_ptr->max_pkt, 2916 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]); 2917 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n", 2918 l_ptr->next_in_no - l_ptr->stats.recv_info, 2919 l_ptr->stats.recv_fragments, 2920 l_ptr->stats.recv_fragmented, 2921 l_ptr->stats.recv_bundles, 2922 l_ptr->stats.recv_bundled); 2923 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n", 2924 l_ptr->next_out_no - l_ptr->stats.sent_info, 2925 l_ptr->stats.sent_fragments, 2926 l_ptr->stats.sent_fragmented, 2927 l_ptr->stats.sent_bundles, 2928 l_ptr->stats.sent_bundled); 2929 profile_total = l_ptr->stats.msg_length_counts; 2930 if (!profile_total) 2931 profile_total = 1; 2932 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n" 2933 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% " 2934 "-16384:%u%% -32768:%u%% -66000:%u%%\n", 2935 l_ptr->stats.msg_length_counts, 2936 l_ptr->stats.msg_lengths_total / profile_total, 2937 percent(l_ptr->stats.msg_length_profile[0], profile_total), 2938 percent(l_ptr->stats.msg_length_profile[1], profile_total), 2939 percent(l_ptr->stats.msg_length_profile[2], profile_total), 2940 percent(l_ptr->stats.msg_length_profile[3], profile_total), 2941 percent(l_ptr->stats.msg_length_profile[4], profile_total), 2942 percent(l_ptr->stats.msg_length_profile[5], profile_total), 2943 percent(l_ptr->stats.msg_length_profile[6], profile_total)); 2944 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n", 2945 l_ptr->stats.recv_states, 2946 l_ptr->stats.recv_probes, 2947 l_ptr->stats.recv_nacks, 2948 l_ptr->stats.deferred_recv, 2949 l_ptr->stats.duplicates); 2950 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n", 2951 l_ptr->stats.sent_states, 2952 l_ptr->stats.sent_probes, 2953 l_ptr->stats.sent_nacks, 2954 l_ptr->stats.sent_acks, 2955 l_ptr->stats.retransmitted); 2956 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n", 2957 l_ptr->stats.bearer_congs, 2958 l_ptr->stats.link_congs, 2959 l_ptr->stats.max_queue_sz, 2960 l_ptr->stats.queue_sz_counts 2961 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts) 2962 : 0); 2963 2964 tipc_node_unlock(node); 2965 read_unlock_bh(&tipc_net_lock); 2966 return tipc_printbuf_validate(&pb); 2967 } 2968 2969 #define MAX_LINK_STATS_INFO 2000 2970 2971 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space) 2972 { 2973 struct sk_buff *buf; 2974 struct tlv_desc *rep_tlv; 2975 int str_len; 2976 2977 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME)) 2978 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 2979 2980 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO)); 2981 if (!buf) 2982 return NULL; 2983 2984 rep_tlv = (struct tlv_desc *)buf->data; 2985 2986 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area), 2987 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO); 2988 if (!str_len) { 2989 buf_discard(buf); 2990 return tipc_cfg_reply_error_string("link not found"); 2991 } 2992 2993 skb_put(buf, TLV_SPACE(str_len)); 2994 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len); 2995 2996 return buf; 2997 } 2998 2999 /** 3000 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination 3001 * @dest: network address of destination node 3002 * @selector: used to select from set of active links 3003 * 3004 * If no active link can be found, uses default maximum packet size. 3005 */ 3006 3007 u32 tipc_link_get_max_pkt(u32 dest, u32 selector) 3008 { 3009 struct tipc_node *n_ptr; 3010 struct link *l_ptr; 3011 u32 res = MAX_PKT_DEFAULT; 3012 3013 if (dest == tipc_own_addr) 3014 return MAX_MSG_SIZE; 3015 3016 read_lock_bh(&tipc_net_lock); 3017 n_ptr = tipc_node_find(dest); 3018 if (n_ptr) { 3019 tipc_node_lock(n_ptr); 3020 l_ptr = n_ptr->active_links[selector & 1]; 3021 if (l_ptr) 3022 res = l_ptr->max_pkt; 3023 tipc_node_unlock(n_ptr); 3024 } 3025 read_unlock_bh(&tipc_net_lock); 3026 return res; 3027 } 3028 3029 static void link_print(struct link *l_ptr, const char *str) 3030 { 3031 char print_area[256]; 3032 struct print_buf pb; 3033 struct print_buf *buf = &pb; 3034 3035 tipc_printbuf_init(buf, print_area, sizeof(print_area)); 3036 3037 tipc_printf(buf, str); 3038 tipc_printf(buf, "Link %x<%s>:", 3039 l_ptr->addr, l_ptr->b_ptr->name); 3040 3041 #ifdef CONFIG_TIPC_DEBUG 3042 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr)) 3043 goto print_state; 3044 3045 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no)); 3046 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no)); 3047 tipc_printf(buf, "SQUE"); 3048 if (l_ptr->first_out) { 3049 tipc_printf(buf, "[%u..", msg_seqno(buf_msg(l_ptr->first_out))); 3050 if (l_ptr->next_out) 3051 tipc_printf(buf, "%u..", 3052 msg_seqno(buf_msg(l_ptr->next_out))); 3053 tipc_printf(buf, "%u]", msg_seqno(buf_msg(l_ptr->last_out))); 3054 if ((mod(msg_seqno(buf_msg(l_ptr->last_out)) - 3055 msg_seqno(buf_msg(l_ptr->first_out))) 3056 != (l_ptr->out_queue_size - 1)) || 3057 (l_ptr->last_out->next != NULL)) { 3058 tipc_printf(buf, "\nSend queue inconsistency\n"); 3059 tipc_printf(buf, "first_out= %p ", l_ptr->first_out); 3060 tipc_printf(buf, "next_out= %p ", l_ptr->next_out); 3061 tipc_printf(buf, "last_out= %p ", l_ptr->last_out); 3062 } 3063 } else 3064 tipc_printf(buf, "[]"); 3065 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size); 3066 if (l_ptr->oldest_deferred_in) { 3067 u32 o = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); 3068 u32 n = msg_seqno(buf_msg(l_ptr->newest_deferred_in)); 3069 tipc_printf(buf, ":RQUE[%u..%u]", o, n); 3070 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) { 3071 tipc_printf(buf, ":RQSIZ(%u)", 3072 l_ptr->deferred_inqueue_sz); 3073 } 3074 } 3075 print_state: 3076 #endif 3077 3078 if (link_working_unknown(l_ptr)) 3079 tipc_printf(buf, ":WU"); 3080 else if (link_reset_reset(l_ptr)) 3081 tipc_printf(buf, ":RR"); 3082 else if (link_reset_unknown(l_ptr)) 3083 tipc_printf(buf, ":RU"); 3084 else if (link_working_working(l_ptr)) 3085 tipc_printf(buf, ":WW"); 3086 tipc_printf(buf, "\n"); 3087 3088 tipc_printbuf_validate(buf); 3089 info("%s", print_area); 3090 } 3091 3092