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, u32 destnode); 96 static void link_check_defragm_bufs(struct link *l_ptr); 97 static void link_state_event(struct link *l_ptr, u32 event); 98 static void link_reset_statistics(struct link *l_ptr); 99 static void link_print(struct link *l_ptr, const char *str); 100 static void link_start(struct link *l_ptr); 101 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf); 102 103 /* 104 * Simple link routines 105 */ 106 107 static unsigned int align(unsigned int i) 108 { 109 return (i + 3) & ~3u; 110 } 111 112 static void link_init_max_pkt(struct link *l_ptr) 113 { 114 u32 max_pkt; 115 116 max_pkt = (l_ptr->b_ptr->mtu & ~3); 117 if (max_pkt > MAX_MSG_SIZE) 118 max_pkt = MAX_MSG_SIZE; 119 120 l_ptr->max_pkt_target = max_pkt; 121 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT) 122 l_ptr->max_pkt = l_ptr->max_pkt_target; 123 else 124 l_ptr->max_pkt = MAX_PKT_DEFAULT; 125 126 l_ptr->max_pkt_probes = 0; 127 } 128 129 static u32 link_next_sent(struct link *l_ptr) 130 { 131 if (l_ptr->next_out) 132 return msg_seqno(buf_msg(l_ptr->next_out)); 133 return mod(l_ptr->next_out_no); 134 } 135 136 static u32 link_last_sent(struct link *l_ptr) 137 { 138 return mod(link_next_sent(l_ptr) - 1); 139 } 140 141 /* 142 * Simple non-static link routines (i.e. referenced outside this file) 143 */ 144 145 int tipc_link_is_up(struct link *l_ptr) 146 { 147 if (!l_ptr) 148 return 0; 149 return link_working_working(l_ptr) || link_working_unknown(l_ptr); 150 } 151 152 int tipc_link_is_active(struct link *l_ptr) 153 { 154 return (l_ptr->owner->active_links[0] == l_ptr) || 155 (l_ptr->owner->active_links[1] == l_ptr); 156 } 157 158 /** 159 * link_name_validate - validate & (optionally) deconstruct link name 160 * @name - ptr to link name string 161 * @name_parts - ptr to area for link name components (or NULL if not needed) 162 * 163 * Returns 1 if link name is valid, otherwise 0. 164 */ 165 166 static int link_name_validate(const char *name, struct link_name *name_parts) 167 { 168 char name_copy[TIPC_MAX_LINK_NAME]; 169 char *addr_local; 170 char *if_local; 171 char *addr_peer; 172 char *if_peer; 173 char dummy; 174 u32 z_local, c_local, n_local; 175 u32 z_peer, c_peer, n_peer; 176 u32 if_local_len; 177 u32 if_peer_len; 178 179 /* copy link name & ensure length is OK */ 180 181 name_copy[TIPC_MAX_LINK_NAME - 1] = 0; 182 /* need above in case non-Posix strncpy() doesn't pad with nulls */ 183 strncpy(name_copy, name, TIPC_MAX_LINK_NAME); 184 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0) 185 return 0; 186 187 /* ensure all component parts of link name are present */ 188 189 addr_local = name_copy; 190 if_local = strchr(addr_local, ':'); 191 if (if_local == NULL) 192 return 0; 193 *(if_local++) = 0; 194 addr_peer = strchr(if_local, '-'); 195 if (addr_peer == NULL) 196 return 0; 197 *(addr_peer++) = 0; 198 if_local_len = addr_peer - if_local; 199 if_peer = strchr(addr_peer, ':'); 200 if (if_peer == NULL) 201 return 0; 202 *(if_peer++) = 0; 203 if_peer_len = strlen(if_peer) + 1; 204 205 /* validate component parts of link name */ 206 207 if ((sscanf(addr_local, "%u.%u.%u%c", 208 &z_local, &c_local, &n_local, &dummy) != 3) || 209 (sscanf(addr_peer, "%u.%u.%u%c", 210 &z_peer, &c_peer, &n_peer, &dummy) != 3) || 211 (z_local > 255) || (c_local > 4095) || (n_local > 4095) || 212 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) || 213 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) || 214 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) || 215 (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) || 216 (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1))) 217 return 0; 218 219 /* return link name components, if necessary */ 220 221 if (name_parts) { 222 name_parts->addr_local = tipc_addr(z_local, c_local, n_local); 223 strcpy(name_parts->if_local, if_local); 224 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer); 225 strcpy(name_parts->if_peer, if_peer); 226 } 227 return 1; 228 } 229 230 /** 231 * link_timeout - handle expiration of link timer 232 * @l_ptr: pointer to link 233 * 234 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict 235 * with tipc_link_delete(). (There is no risk that the node will be deleted by 236 * another thread because tipc_link_delete() always cancels the link timer before 237 * tipc_node_delete() is called.) 238 */ 239 240 static void link_timeout(struct link *l_ptr) 241 { 242 tipc_node_lock(l_ptr->owner); 243 244 /* update counters used in statistical profiling of send traffic */ 245 246 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size; 247 l_ptr->stats.queue_sz_counts++; 248 249 if (l_ptr->first_out) { 250 struct tipc_msg *msg = buf_msg(l_ptr->first_out); 251 u32 length = msg_size(msg); 252 253 if ((msg_user(msg) == MSG_FRAGMENTER) && 254 (msg_type(msg) == FIRST_FRAGMENT)) { 255 length = msg_size(msg_get_wrapped(msg)); 256 } 257 if (length) { 258 l_ptr->stats.msg_lengths_total += length; 259 l_ptr->stats.msg_length_counts++; 260 if (length <= 64) 261 l_ptr->stats.msg_length_profile[0]++; 262 else if (length <= 256) 263 l_ptr->stats.msg_length_profile[1]++; 264 else if (length <= 1024) 265 l_ptr->stats.msg_length_profile[2]++; 266 else if (length <= 4096) 267 l_ptr->stats.msg_length_profile[3]++; 268 else if (length <= 16384) 269 l_ptr->stats.msg_length_profile[4]++; 270 else if (length <= 32768) 271 l_ptr->stats.msg_length_profile[5]++; 272 else 273 l_ptr->stats.msg_length_profile[6]++; 274 } 275 } 276 277 /* do all other link processing performed on a periodic basis */ 278 279 link_check_defragm_bufs(l_ptr); 280 281 link_state_event(l_ptr, TIMEOUT_EVT); 282 283 if (l_ptr->next_out) 284 tipc_link_push_queue(l_ptr); 285 286 tipc_node_unlock(l_ptr->owner); 287 } 288 289 static void link_set_timer(struct link *l_ptr, u32 time) 290 { 291 k_start_timer(&l_ptr->timer, time); 292 } 293 294 /** 295 * tipc_link_create - create a new link 296 * @n_ptr: pointer to associated node 297 * @b_ptr: pointer to associated bearer 298 * @media_addr: media address to use when sending messages over link 299 * 300 * Returns pointer to link. 301 */ 302 303 struct link *tipc_link_create(struct tipc_node *n_ptr, 304 struct tipc_bearer *b_ptr, 305 const struct tipc_media_addr *media_addr) 306 { 307 struct link *l_ptr; 308 struct tipc_msg *msg; 309 char *if_name; 310 char addr_string[16]; 311 u32 peer = n_ptr->addr; 312 313 if (n_ptr->link_cnt >= 2) { 314 tipc_addr_string_fill(addr_string, n_ptr->addr); 315 err("Attempt to establish third link to %s\n", addr_string); 316 return NULL; 317 } 318 319 if (n_ptr->links[b_ptr->identity]) { 320 tipc_addr_string_fill(addr_string, n_ptr->addr); 321 err("Attempt to establish second link on <%s> to %s\n", 322 b_ptr->name, addr_string); 323 return NULL; 324 } 325 326 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC); 327 if (!l_ptr) { 328 warn("Link creation failed, no memory\n"); 329 return NULL; 330 } 331 332 l_ptr->addr = peer; 333 if_name = strchr(b_ptr->name, ':') + 1; 334 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:", 335 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr), 336 tipc_node(tipc_own_addr), 337 if_name, 338 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer)); 339 /* note: peer i/f is appended to link name by reset/activate */ 340 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr)); 341 l_ptr->owner = n_ptr; 342 l_ptr->checkpoint = 1; 343 l_ptr->b_ptr = b_ptr; 344 link_set_supervision_props(l_ptr, b_ptr->media->tolerance); 345 l_ptr->state = RESET_UNKNOWN; 346 347 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg; 348 msg = l_ptr->pmsg; 349 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr); 350 msg_set_size(msg, sizeof(l_ptr->proto_msg)); 351 msg_set_session(msg, (tipc_random & 0xffff)); 352 msg_set_bearer_id(msg, b_ptr->identity); 353 strcpy((char *)msg_data(msg), if_name); 354 355 l_ptr->priority = b_ptr->priority; 356 tipc_link_set_queue_limits(l_ptr, b_ptr->media->window); 357 358 link_init_max_pkt(l_ptr); 359 360 l_ptr->next_out_no = 1; 361 INIT_LIST_HEAD(&l_ptr->waiting_ports); 362 363 link_reset_statistics(l_ptr); 364 365 tipc_node_attach_link(n_ptr, l_ptr); 366 367 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr); 368 list_add_tail(&l_ptr->link_list, &b_ptr->links); 369 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr); 370 371 return l_ptr; 372 } 373 374 /** 375 * tipc_link_delete - delete a link 376 * @l_ptr: pointer to link 377 * 378 * Note: 'tipc_net_lock' is write_locked, bearer is locked. 379 * This routine must not grab the node lock until after link timer cancellation 380 * to avoid a potential deadlock situation. 381 */ 382 383 void tipc_link_delete(struct link *l_ptr) 384 { 385 if (!l_ptr) { 386 err("Attempt to delete non-existent link\n"); 387 return; 388 } 389 390 k_cancel_timer(&l_ptr->timer); 391 392 tipc_node_lock(l_ptr->owner); 393 tipc_link_reset(l_ptr); 394 tipc_node_detach_link(l_ptr->owner, l_ptr); 395 tipc_link_stop(l_ptr); 396 list_del_init(&l_ptr->link_list); 397 tipc_node_unlock(l_ptr->owner); 398 k_term_timer(&l_ptr->timer); 399 kfree(l_ptr); 400 } 401 402 static void link_start(struct link *l_ptr) 403 { 404 tipc_node_lock(l_ptr->owner); 405 link_state_event(l_ptr, STARTING_EVT); 406 tipc_node_unlock(l_ptr->owner); 407 } 408 409 /** 410 * link_schedule_port - schedule port for deferred sending 411 * @l_ptr: pointer to link 412 * @origport: reference to sending port 413 * @sz: amount of data to be sent 414 * 415 * Schedules port for renewed sending of messages after link congestion 416 * has abated. 417 */ 418 419 static int link_schedule_port(struct link *l_ptr, u32 origport, u32 sz) 420 { 421 struct tipc_port *p_ptr; 422 423 spin_lock_bh(&tipc_port_list_lock); 424 p_ptr = tipc_port_lock(origport); 425 if (p_ptr) { 426 if (!p_ptr->wakeup) 427 goto exit; 428 if (!list_empty(&p_ptr->wait_list)) 429 goto exit; 430 p_ptr->congested = 1; 431 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt); 432 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports); 433 l_ptr->stats.link_congs++; 434 exit: 435 tipc_port_unlock(p_ptr); 436 } 437 spin_unlock_bh(&tipc_port_list_lock); 438 return -ELINKCONG; 439 } 440 441 void tipc_link_wakeup_ports(struct link *l_ptr, int all) 442 { 443 struct tipc_port *p_ptr; 444 struct tipc_port *temp_p_ptr; 445 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size; 446 447 if (all) 448 win = 100000; 449 if (win <= 0) 450 return; 451 if (!spin_trylock_bh(&tipc_port_list_lock)) 452 return; 453 if (link_congested(l_ptr)) 454 goto exit; 455 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports, 456 wait_list) { 457 if (win <= 0) 458 break; 459 list_del_init(&p_ptr->wait_list); 460 spin_lock_bh(p_ptr->lock); 461 p_ptr->congested = 0; 462 p_ptr->wakeup(p_ptr); 463 win -= p_ptr->waiting_pkts; 464 spin_unlock_bh(p_ptr->lock); 465 } 466 467 exit: 468 spin_unlock_bh(&tipc_port_list_lock); 469 } 470 471 /** 472 * link_release_outqueue - purge link's outbound message queue 473 * @l_ptr: pointer to link 474 */ 475 476 static void link_release_outqueue(struct link *l_ptr) 477 { 478 struct sk_buff *buf = l_ptr->first_out; 479 struct sk_buff *next; 480 481 while (buf) { 482 next = buf->next; 483 buf_discard(buf); 484 buf = next; 485 } 486 l_ptr->first_out = NULL; 487 l_ptr->out_queue_size = 0; 488 } 489 490 /** 491 * tipc_link_reset_fragments - purge link's inbound message fragments queue 492 * @l_ptr: pointer to link 493 */ 494 495 void tipc_link_reset_fragments(struct link *l_ptr) 496 { 497 struct sk_buff *buf = l_ptr->defragm_buf; 498 struct sk_buff *next; 499 500 while (buf) { 501 next = buf->next; 502 buf_discard(buf); 503 buf = next; 504 } 505 l_ptr->defragm_buf = NULL; 506 } 507 508 /** 509 * tipc_link_stop - purge all inbound and outbound messages associated with link 510 * @l_ptr: pointer to link 511 */ 512 513 void tipc_link_stop(struct link *l_ptr) 514 { 515 struct sk_buff *buf; 516 struct sk_buff *next; 517 518 buf = l_ptr->oldest_deferred_in; 519 while (buf) { 520 next = buf->next; 521 buf_discard(buf); 522 buf = next; 523 } 524 525 buf = l_ptr->first_out; 526 while (buf) { 527 next = buf->next; 528 buf_discard(buf); 529 buf = next; 530 } 531 532 tipc_link_reset_fragments(l_ptr); 533 534 buf_discard(l_ptr->proto_msg_queue); 535 l_ptr->proto_msg_queue = NULL; 536 } 537 538 /* LINK EVENT CODE IS NOT SUPPORTED AT PRESENT */ 539 #define link_send_event(fcn, l_ptr, up) do { } while (0) 540 541 void tipc_link_reset(struct link *l_ptr) 542 { 543 struct sk_buff *buf; 544 u32 prev_state = l_ptr->state; 545 u32 checkpoint = l_ptr->next_in_no; 546 int was_active_link = tipc_link_is_active(l_ptr); 547 548 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff)); 549 550 /* Link is down, accept any session */ 551 l_ptr->peer_session = INVALID_SESSION; 552 553 /* Prepare for max packet size negotiation */ 554 link_init_max_pkt(l_ptr); 555 556 l_ptr->state = RESET_UNKNOWN; 557 558 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET)) 559 return; 560 561 tipc_node_link_down(l_ptr->owner, l_ptr); 562 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr); 563 564 if (was_active_link && tipc_node_active_links(l_ptr->owner) && 565 l_ptr->owner->permit_changeover) { 566 l_ptr->reset_checkpoint = checkpoint; 567 l_ptr->exp_msg_count = START_CHANGEOVER; 568 } 569 570 /* Clean up all queues: */ 571 572 link_release_outqueue(l_ptr); 573 buf_discard(l_ptr->proto_msg_queue); 574 l_ptr->proto_msg_queue = NULL; 575 buf = l_ptr->oldest_deferred_in; 576 while (buf) { 577 struct sk_buff *next = buf->next; 578 buf_discard(buf); 579 buf = next; 580 } 581 if (!list_empty(&l_ptr->waiting_ports)) 582 tipc_link_wakeup_ports(l_ptr, 1); 583 584 l_ptr->retransm_queue_head = 0; 585 l_ptr->retransm_queue_size = 0; 586 l_ptr->last_out = NULL; 587 l_ptr->first_out = NULL; 588 l_ptr->next_out = NULL; 589 l_ptr->unacked_window = 0; 590 l_ptr->checkpoint = 1; 591 l_ptr->next_out_no = 1; 592 l_ptr->deferred_inqueue_sz = 0; 593 l_ptr->oldest_deferred_in = NULL; 594 l_ptr->newest_deferred_in = NULL; 595 l_ptr->fsm_msg_cnt = 0; 596 l_ptr->stale_count = 0; 597 link_reset_statistics(l_ptr); 598 599 link_send_event(tipc_cfg_link_event, l_ptr, 0); 600 if (!in_own_cluster(l_ptr->addr)) 601 link_send_event(tipc_disc_link_event, l_ptr, 0); 602 } 603 604 605 static void link_activate(struct link *l_ptr) 606 { 607 l_ptr->next_in_no = l_ptr->stats.recv_info = 1; 608 tipc_node_link_up(l_ptr->owner, l_ptr); 609 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr); 610 link_send_event(tipc_cfg_link_event, l_ptr, 1); 611 if (!in_own_cluster(l_ptr->addr)) 612 link_send_event(tipc_disc_link_event, l_ptr, 1); 613 } 614 615 /** 616 * link_state_event - link finite state machine 617 * @l_ptr: pointer to link 618 * @event: state machine event to process 619 */ 620 621 static void link_state_event(struct link *l_ptr, unsigned event) 622 { 623 struct link *other; 624 u32 cont_intv = l_ptr->continuity_interval; 625 626 if (!l_ptr->started && (event != STARTING_EVT)) 627 return; /* Not yet. */ 628 629 if (link_blocked(l_ptr)) { 630 if (event == TIMEOUT_EVT) 631 link_set_timer(l_ptr, cont_intv); 632 return; /* Changeover going on */ 633 } 634 635 switch (l_ptr->state) { 636 case WORKING_WORKING: 637 switch (event) { 638 case TRAFFIC_MSG_EVT: 639 case ACTIVATE_MSG: 640 break; 641 case TIMEOUT_EVT: 642 if (l_ptr->next_in_no != l_ptr->checkpoint) { 643 l_ptr->checkpoint = l_ptr->next_in_no; 644 if (tipc_bclink_acks_missing(l_ptr->owner)) { 645 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 646 0, 0, 0, 0, 0); 647 l_ptr->fsm_msg_cnt++; 648 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) { 649 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 650 1, 0, 0, 0, 0); 651 l_ptr->fsm_msg_cnt++; 652 } 653 link_set_timer(l_ptr, cont_intv); 654 break; 655 } 656 l_ptr->state = WORKING_UNKNOWN; 657 l_ptr->fsm_msg_cnt = 0; 658 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); 659 l_ptr->fsm_msg_cnt++; 660 link_set_timer(l_ptr, cont_intv / 4); 661 break; 662 case RESET_MSG: 663 info("Resetting link <%s>, requested by peer\n", 664 l_ptr->name); 665 tipc_link_reset(l_ptr); 666 l_ptr->state = RESET_RESET; 667 l_ptr->fsm_msg_cnt = 0; 668 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); 669 l_ptr->fsm_msg_cnt++; 670 link_set_timer(l_ptr, cont_intv); 671 break; 672 default: 673 err("Unknown link event %u in WW state\n", event); 674 } 675 break; 676 case WORKING_UNKNOWN: 677 switch (event) { 678 case TRAFFIC_MSG_EVT: 679 case ACTIVATE_MSG: 680 l_ptr->state = WORKING_WORKING; 681 l_ptr->fsm_msg_cnt = 0; 682 link_set_timer(l_ptr, cont_intv); 683 break; 684 case RESET_MSG: 685 info("Resetting link <%s>, requested by peer " 686 "while probing\n", l_ptr->name); 687 tipc_link_reset(l_ptr); 688 l_ptr->state = RESET_RESET; 689 l_ptr->fsm_msg_cnt = 0; 690 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); 691 l_ptr->fsm_msg_cnt++; 692 link_set_timer(l_ptr, cont_intv); 693 break; 694 case TIMEOUT_EVT: 695 if (l_ptr->next_in_no != l_ptr->checkpoint) { 696 l_ptr->state = WORKING_WORKING; 697 l_ptr->fsm_msg_cnt = 0; 698 l_ptr->checkpoint = l_ptr->next_in_no; 699 if (tipc_bclink_acks_missing(l_ptr->owner)) { 700 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 701 0, 0, 0, 0, 0); 702 l_ptr->fsm_msg_cnt++; 703 } 704 link_set_timer(l_ptr, cont_intv); 705 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) { 706 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 707 1, 0, 0, 0, 0); 708 l_ptr->fsm_msg_cnt++; 709 link_set_timer(l_ptr, cont_intv / 4); 710 } else { /* Link has failed */ 711 warn("Resetting link <%s>, peer not responding\n", 712 l_ptr->name); 713 tipc_link_reset(l_ptr); 714 l_ptr->state = RESET_UNKNOWN; 715 l_ptr->fsm_msg_cnt = 0; 716 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 717 0, 0, 0, 0, 0); 718 l_ptr->fsm_msg_cnt++; 719 link_set_timer(l_ptr, cont_intv); 720 } 721 break; 722 default: 723 err("Unknown link event %u in WU state\n", event); 724 } 725 break; 726 case RESET_UNKNOWN: 727 switch (event) { 728 case TRAFFIC_MSG_EVT: 729 break; 730 case ACTIVATE_MSG: 731 other = l_ptr->owner->active_links[0]; 732 if (other && link_working_unknown(other)) 733 break; 734 l_ptr->state = WORKING_WORKING; 735 l_ptr->fsm_msg_cnt = 0; 736 link_activate(l_ptr); 737 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); 738 l_ptr->fsm_msg_cnt++; 739 link_set_timer(l_ptr, cont_intv); 740 break; 741 case RESET_MSG: 742 l_ptr->state = RESET_RESET; 743 l_ptr->fsm_msg_cnt = 0; 744 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0); 745 l_ptr->fsm_msg_cnt++; 746 link_set_timer(l_ptr, cont_intv); 747 break; 748 case STARTING_EVT: 749 l_ptr->started = 1; 750 /* fall through */ 751 case TIMEOUT_EVT: 752 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0); 753 l_ptr->fsm_msg_cnt++; 754 link_set_timer(l_ptr, cont_intv); 755 break; 756 default: 757 err("Unknown link event %u in RU state\n", event); 758 } 759 break; 760 case RESET_RESET: 761 switch (event) { 762 case TRAFFIC_MSG_EVT: 763 case ACTIVATE_MSG: 764 other = l_ptr->owner->active_links[0]; 765 if (other && link_working_unknown(other)) 766 break; 767 l_ptr->state = WORKING_WORKING; 768 l_ptr->fsm_msg_cnt = 0; 769 link_activate(l_ptr); 770 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); 771 l_ptr->fsm_msg_cnt++; 772 link_set_timer(l_ptr, cont_intv); 773 break; 774 case RESET_MSG: 775 break; 776 case TIMEOUT_EVT: 777 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); 778 l_ptr->fsm_msg_cnt++; 779 link_set_timer(l_ptr, cont_intv); 780 break; 781 default: 782 err("Unknown link event %u in RR state\n", event); 783 } 784 break; 785 default: 786 err("Unknown link state %u/%u\n", l_ptr->state, event); 787 } 788 } 789 790 /* 791 * link_bundle_buf(): Append contents of a buffer to 792 * the tail of an existing one. 793 */ 794 795 static int link_bundle_buf(struct link *l_ptr, 796 struct sk_buff *bundler, 797 struct sk_buff *buf) 798 { 799 struct tipc_msg *bundler_msg = buf_msg(bundler); 800 struct tipc_msg *msg = buf_msg(buf); 801 u32 size = msg_size(msg); 802 u32 bundle_size = msg_size(bundler_msg); 803 u32 to_pos = align(bundle_size); 804 u32 pad = to_pos - bundle_size; 805 806 if (msg_user(bundler_msg) != MSG_BUNDLER) 807 return 0; 808 if (msg_type(bundler_msg) != OPEN_MSG) 809 return 0; 810 if (skb_tailroom(bundler) < (pad + size)) 811 return 0; 812 if (l_ptr->max_pkt < (to_pos + size)) 813 return 0; 814 815 skb_put(bundler, pad + size); 816 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size); 817 msg_set_size(bundler_msg, to_pos + size); 818 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1); 819 buf_discard(buf); 820 l_ptr->stats.sent_bundled++; 821 return 1; 822 } 823 824 static void link_add_to_outqueue(struct link *l_ptr, 825 struct sk_buff *buf, 826 struct tipc_msg *msg) 827 { 828 u32 ack = mod(l_ptr->next_in_no - 1); 829 u32 seqno = mod(l_ptr->next_out_no++); 830 831 msg_set_word(msg, 2, ((ack << 16) | seqno)); 832 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 833 buf->next = NULL; 834 if (l_ptr->first_out) { 835 l_ptr->last_out->next = buf; 836 l_ptr->last_out = buf; 837 } else 838 l_ptr->first_out = l_ptr->last_out = buf; 839 840 l_ptr->out_queue_size++; 841 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz) 842 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size; 843 } 844 845 /* 846 * tipc_link_send_buf() is the 'full path' for messages, called from 847 * inside TIPC when the 'fast path' in tipc_send_buf 848 * has failed, and from link_send() 849 */ 850 851 int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf) 852 { 853 struct tipc_msg *msg = buf_msg(buf); 854 u32 size = msg_size(msg); 855 u32 dsz = msg_data_sz(msg); 856 u32 queue_size = l_ptr->out_queue_size; 857 u32 imp = tipc_msg_tot_importance(msg); 858 u32 queue_limit = l_ptr->queue_limit[imp]; 859 u32 max_packet = l_ptr->max_pkt; 860 861 msg_set_prevnode(msg, tipc_own_addr); /* If routed message */ 862 863 /* Match msg importance against queue limits: */ 864 865 if (unlikely(queue_size >= queue_limit)) { 866 if (imp <= TIPC_CRITICAL_IMPORTANCE) { 867 return link_schedule_port(l_ptr, msg_origport(msg), 868 size); 869 } 870 buf_discard(buf); 871 if (imp > CONN_MANAGER) { 872 warn("Resetting link <%s>, send queue full", l_ptr->name); 873 tipc_link_reset(l_ptr); 874 } 875 return dsz; 876 } 877 878 /* Fragmentation needed ? */ 879 880 if (size > max_packet) 881 return link_send_long_buf(l_ptr, buf); 882 883 /* Packet can be queued or sent: */ 884 885 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) && 886 !link_congested(l_ptr))) { 887 link_add_to_outqueue(l_ptr, buf, msg); 888 889 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) { 890 l_ptr->unacked_window = 0; 891 } else { 892 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 893 l_ptr->stats.bearer_congs++; 894 l_ptr->next_out = buf; 895 } 896 return dsz; 897 } 898 /* Congestion: can message be bundled ?: */ 899 900 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) && 901 (msg_user(msg) != MSG_FRAGMENTER)) { 902 903 /* Try adding message to an existing bundle */ 904 905 if (l_ptr->next_out && 906 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) { 907 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr); 908 return dsz; 909 } 910 911 /* Try creating a new bundle */ 912 913 if (size <= max_packet * 2 / 3) { 914 struct sk_buff *bundler = tipc_buf_acquire(max_packet); 915 struct tipc_msg bundler_hdr; 916 917 if (bundler) { 918 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG, 919 INT_H_SIZE, l_ptr->addr); 920 skb_copy_to_linear_data(bundler, &bundler_hdr, 921 INT_H_SIZE); 922 skb_trim(bundler, INT_H_SIZE); 923 link_bundle_buf(l_ptr, bundler, buf); 924 buf = bundler; 925 msg = buf_msg(buf); 926 l_ptr->stats.sent_bundles++; 927 } 928 } 929 } 930 if (!l_ptr->next_out) 931 l_ptr->next_out = buf; 932 link_add_to_outqueue(l_ptr, buf, msg); 933 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr); 934 return dsz; 935 } 936 937 /* 938 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has 939 * not been selected yet, and the the owner node is not locked 940 * Called by TIPC internal users, e.g. the name distributor 941 */ 942 943 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector) 944 { 945 struct link *l_ptr; 946 struct tipc_node *n_ptr; 947 int res = -ELINKCONG; 948 949 read_lock_bh(&tipc_net_lock); 950 n_ptr = tipc_node_find(dest); 951 if (n_ptr) { 952 tipc_node_lock(n_ptr); 953 l_ptr = n_ptr->active_links[selector & 1]; 954 if (l_ptr) 955 res = tipc_link_send_buf(l_ptr, buf); 956 else 957 buf_discard(buf); 958 tipc_node_unlock(n_ptr); 959 } else { 960 buf_discard(buf); 961 } 962 read_unlock_bh(&tipc_net_lock); 963 return res; 964 } 965 966 /* 967 * link_send_buf_fast: Entry for data messages where the 968 * destination link is known and the header is complete, 969 * inclusive total message length. Very time critical. 970 * Link is locked. Returns user data length. 971 */ 972 973 static int link_send_buf_fast(struct link *l_ptr, struct sk_buff *buf, 974 u32 *used_max_pkt) 975 { 976 struct tipc_msg *msg = buf_msg(buf); 977 int res = msg_data_sz(msg); 978 979 if (likely(!link_congested(l_ptr))) { 980 if (likely(msg_size(msg) <= l_ptr->max_pkt)) { 981 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) { 982 link_add_to_outqueue(l_ptr, buf, msg); 983 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, 984 &l_ptr->media_addr))) { 985 l_ptr->unacked_window = 0; 986 return res; 987 } 988 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 989 l_ptr->stats.bearer_congs++; 990 l_ptr->next_out = buf; 991 return res; 992 } 993 } else 994 *used_max_pkt = l_ptr->max_pkt; 995 } 996 return tipc_link_send_buf(l_ptr, buf); /* All other cases */ 997 } 998 999 /* 1000 * tipc_send_buf_fast: Entry for data messages where the 1001 * destination node is known and the header is complete, 1002 * inclusive total message length. 1003 * Returns user data length. 1004 */ 1005 int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode) 1006 { 1007 struct link *l_ptr; 1008 struct tipc_node *n_ptr; 1009 int res; 1010 u32 selector = msg_origport(buf_msg(buf)) & 1; 1011 u32 dummy; 1012 1013 if (destnode == tipc_own_addr) 1014 return tipc_port_recv_msg(buf); 1015 1016 read_lock_bh(&tipc_net_lock); 1017 n_ptr = tipc_node_find(destnode); 1018 if (likely(n_ptr)) { 1019 tipc_node_lock(n_ptr); 1020 l_ptr = n_ptr->active_links[selector]; 1021 if (likely(l_ptr)) { 1022 res = link_send_buf_fast(l_ptr, buf, &dummy); 1023 tipc_node_unlock(n_ptr); 1024 read_unlock_bh(&tipc_net_lock); 1025 return res; 1026 } 1027 tipc_node_unlock(n_ptr); 1028 } 1029 read_unlock_bh(&tipc_net_lock); 1030 res = msg_data_sz(buf_msg(buf)); 1031 tipc_reject_msg(buf, TIPC_ERR_NO_NODE); 1032 return res; 1033 } 1034 1035 1036 /* 1037 * tipc_link_send_sections_fast: Entry for messages where the 1038 * destination processor is known and the header is complete, 1039 * except for total message length. 1040 * Returns user data length or errno. 1041 */ 1042 int tipc_link_send_sections_fast(struct tipc_port *sender, 1043 struct iovec const *msg_sect, 1044 const u32 num_sect, 1045 u32 destaddr) 1046 { 1047 struct tipc_msg *hdr = &sender->phdr; 1048 struct link *l_ptr; 1049 struct sk_buff *buf; 1050 struct tipc_node *node; 1051 int res; 1052 u32 selector = msg_origport(hdr) & 1; 1053 1054 again: 1055 /* 1056 * Try building message using port's max_pkt hint. 1057 * (Must not hold any locks while building message.) 1058 */ 1059 1060 res = tipc_msg_build(hdr, msg_sect, num_sect, sender->max_pkt, 1061 !sender->user_port, &buf); 1062 1063 read_lock_bh(&tipc_net_lock); 1064 node = tipc_node_find(destaddr); 1065 if (likely(node)) { 1066 tipc_node_lock(node); 1067 l_ptr = node->active_links[selector]; 1068 if (likely(l_ptr)) { 1069 if (likely(buf)) { 1070 res = link_send_buf_fast(l_ptr, buf, 1071 &sender->max_pkt); 1072 if (unlikely(res < 0)) 1073 buf_discard(buf); 1074 exit: 1075 tipc_node_unlock(node); 1076 read_unlock_bh(&tipc_net_lock); 1077 return res; 1078 } 1079 1080 /* Exit if build request was invalid */ 1081 1082 if (unlikely(res < 0)) 1083 goto exit; 1084 1085 /* Exit if link (or bearer) is congested */ 1086 1087 if (link_congested(l_ptr) || 1088 !list_empty(&l_ptr->b_ptr->cong_links)) { 1089 res = link_schedule_port(l_ptr, 1090 sender->ref, res); 1091 goto exit; 1092 } 1093 1094 /* 1095 * Message size exceeds max_pkt hint; update hint, 1096 * then re-try fast path or fragment the message 1097 */ 1098 1099 sender->max_pkt = l_ptr->max_pkt; 1100 tipc_node_unlock(node); 1101 read_unlock_bh(&tipc_net_lock); 1102 1103 1104 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt) 1105 goto again; 1106 1107 return link_send_sections_long(sender, msg_sect, 1108 num_sect, destaddr); 1109 } 1110 tipc_node_unlock(node); 1111 } 1112 read_unlock_bh(&tipc_net_lock); 1113 1114 /* Couldn't find a link to the destination node */ 1115 1116 if (buf) 1117 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE); 1118 if (res >= 0) 1119 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect, 1120 TIPC_ERR_NO_NODE); 1121 return res; 1122 } 1123 1124 /* 1125 * link_send_sections_long(): Entry for long messages where the 1126 * destination node is known and the header is complete, 1127 * inclusive total message length. 1128 * Link and bearer congestion status have been checked to be ok, 1129 * and are ignored if they change. 1130 * 1131 * Note that fragments do not use the full link MTU so that they won't have 1132 * to undergo refragmentation if link changeover causes them to be sent 1133 * over another link with an additional tunnel header added as prefix. 1134 * (Refragmentation will still occur if the other link has a smaller MTU.) 1135 * 1136 * Returns user data length or errno. 1137 */ 1138 static int link_send_sections_long(struct tipc_port *sender, 1139 struct iovec const *msg_sect, 1140 u32 num_sect, 1141 u32 destaddr) 1142 { 1143 struct link *l_ptr; 1144 struct tipc_node *node; 1145 struct tipc_msg *hdr = &sender->phdr; 1146 u32 dsz = msg_data_sz(hdr); 1147 u32 max_pkt, fragm_sz, rest; 1148 struct tipc_msg fragm_hdr; 1149 struct sk_buff *buf, *buf_chain, *prev; 1150 u32 fragm_crs, fragm_rest, hsz, sect_rest; 1151 const unchar *sect_crs; 1152 int curr_sect; 1153 u32 fragm_no; 1154 1155 again: 1156 fragm_no = 1; 1157 max_pkt = sender->max_pkt - INT_H_SIZE; 1158 /* leave room for tunnel header in case of link changeover */ 1159 fragm_sz = max_pkt - INT_H_SIZE; 1160 /* leave room for fragmentation header in each fragment */ 1161 rest = dsz; 1162 fragm_crs = 0; 1163 fragm_rest = 0; 1164 sect_rest = 0; 1165 sect_crs = NULL; 1166 curr_sect = -1; 1167 1168 /* Prepare reusable fragment header: */ 1169 1170 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT, 1171 INT_H_SIZE, msg_destnode(hdr)); 1172 msg_set_link_selector(&fragm_hdr, sender->ref); 1173 msg_set_size(&fragm_hdr, max_pkt); 1174 msg_set_fragm_no(&fragm_hdr, 1); 1175 1176 /* Prepare header of first fragment: */ 1177 1178 buf_chain = buf = tipc_buf_acquire(max_pkt); 1179 if (!buf) 1180 return -ENOMEM; 1181 buf->next = NULL; 1182 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE); 1183 hsz = msg_hdr_sz(hdr); 1184 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz); 1185 1186 /* Chop up message: */ 1187 1188 fragm_crs = INT_H_SIZE + hsz; 1189 fragm_rest = fragm_sz - hsz; 1190 1191 do { /* For all sections */ 1192 u32 sz; 1193 1194 if (!sect_rest) { 1195 sect_rest = msg_sect[++curr_sect].iov_len; 1196 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base; 1197 } 1198 1199 if (sect_rest < fragm_rest) 1200 sz = sect_rest; 1201 else 1202 sz = fragm_rest; 1203 1204 if (likely(!sender->user_port)) { 1205 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) { 1206 error: 1207 for (; buf_chain; buf_chain = buf) { 1208 buf = buf_chain->next; 1209 buf_discard(buf_chain); 1210 } 1211 return -EFAULT; 1212 } 1213 } else 1214 skb_copy_to_linear_data_offset(buf, fragm_crs, 1215 sect_crs, sz); 1216 sect_crs += sz; 1217 sect_rest -= sz; 1218 fragm_crs += sz; 1219 fragm_rest -= sz; 1220 rest -= sz; 1221 1222 if (!fragm_rest && rest) { 1223 1224 /* Initiate new fragment: */ 1225 if (rest <= fragm_sz) { 1226 fragm_sz = rest; 1227 msg_set_type(&fragm_hdr, LAST_FRAGMENT); 1228 } else { 1229 msg_set_type(&fragm_hdr, FRAGMENT); 1230 } 1231 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE); 1232 msg_set_fragm_no(&fragm_hdr, ++fragm_no); 1233 prev = buf; 1234 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE); 1235 if (!buf) 1236 goto error; 1237 1238 buf->next = NULL; 1239 prev->next = buf; 1240 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE); 1241 fragm_crs = INT_H_SIZE; 1242 fragm_rest = fragm_sz; 1243 } 1244 } while (rest > 0); 1245 1246 /* 1247 * Now we have a buffer chain. Select a link and check 1248 * that packet size is still OK 1249 */ 1250 node = tipc_node_find(destaddr); 1251 if (likely(node)) { 1252 tipc_node_lock(node); 1253 l_ptr = node->active_links[sender->ref & 1]; 1254 if (!l_ptr) { 1255 tipc_node_unlock(node); 1256 goto reject; 1257 } 1258 if (l_ptr->max_pkt < max_pkt) { 1259 sender->max_pkt = l_ptr->max_pkt; 1260 tipc_node_unlock(node); 1261 for (; buf_chain; buf_chain = buf) { 1262 buf = buf_chain->next; 1263 buf_discard(buf_chain); 1264 } 1265 goto again; 1266 } 1267 } else { 1268 reject: 1269 for (; buf_chain; buf_chain = buf) { 1270 buf = buf_chain->next; 1271 buf_discard(buf_chain); 1272 } 1273 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect, 1274 TIPC_ERR_NO_NODE); 1275 } 1276 1277 /* Append whole chain to send queue: */ 1278 1279 buf = buf_chain; 1280 l_ptr->long_msg_seq_no = mod(l_ptr->long_msg_seq_no + 1); 1281 if (!l_ptr->next_out) 1282 l_ptr->next_out = buf_chain; 1283 l_ptr->stats.sent_fragmented++; 1284 while (buf) { 1285 struct sk_buff *next = buf->next; 1286 struct tipc_msg *msg = buf_msg(buf); 1287 1288 l_ptr->stats.sent_fragments++; 1289 msg_set_long_msgno(msg, l_ptr->long_msg_seq_no); 1290 link_add_to_outqueue(l_ptr, buf, msg); 1291 buf = next; 1292 } 1293 1294 /* Send it, if possible: */ 1295 1296 tipc_link_push_queue(l_ptr); 1297 tipc_node_unlock(node); 1298 return dsz; 1299 } 1300 1301 /* 1302 * tipc_link_push_packet: Push one unsent packet to the media 1303 */ 1304 u32 tipc_link_push_packet(struct link *l_ptr) 1305 { 1306 struct sk_buff *buf = l_ptr->first_out; 1307 u32 r_q_size = l_ptr->retransm_queue_size; 1308 u32 r_q_head = l_ptr->retransm_queue_head; 1309 1310 /* Step to position where retransmission failed, if any, */ 1311 /* consider that buffers may have been released in meantime */ 1312 1313 if (r_q_size && buf) { 1314 u32 last = lesser(mod(r_q_head + r_q_size), 1315 link_last_sent(l_ptr)); 1316 u32 first = msg_seqno(buf_msg(buf)); 1317 1318 while (buf && less(first, r_q_head)) { 1319 first = mod(first + 1); 1320 buf = buf->next; 1321 } 1322 l_ptr->retransm_queue_head = r_q_head = first; 1323 l_ptr->retransm_queue_size = r_q_size = mod(last - first); 1324 } 1325 1326 /* Continue retransmission now, if there is anything: */ 1327 1328 if (r_q_size && buf) { 1329 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1)); 1330 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in); 1331 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1332 l_ptr->retransm_queue_head = mod(++r_q_head); 1333 l_ptr->retransm_queue_size = --r_q_size; 1334 l_ptr->stats.retransmitted++; 1335 return 0; 1336 } else { 1337 l_ptr->stats.bearer_congs++; 1338 return PUSH_FAILED; 1339 } 1340 } 1341 1342 /* Send deferred protocol message, if any: */ 1343 1344 buf = l_ptr->proto_msg_queue; 1345 if (buf) { 1346 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1)); 1347 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in); 1348 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1349 l_ptr->unacked_window = 0; 1350 buf_discard(buf); 1351 l_ptr->proto_msg_queue = NULL; 1352 return 0; 1353 } else { 1354 l_ptr->stats.bearer_congs++; 1355 return PUSH_FAILED; 1356 } 1357 } 1358 1359 /* Send one deferred data message, if send window not full: */ 1360 1361 buf = l_ptr->next_out; 1362 if (buf) { 1363 struct tipc_msg *msg = buf_msg(buf); 1364 u32 next = msg_seqno(msg); 1365 u32 first = msg_seqno(buf_msg(l_ptr->first_out)); 1366 1367 if (mod(next - first) < l_ptr->queue_limit[0]) { 1368 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); 1369 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 1370 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1371 if (msg_user(msg) == MSG_BUNDLER) 1372 msg_set_type(msg, CLOSED_MSG); 1373 l_ptr->next_out = buf->next; 1374 return 0; 1375 } else { 1376 l_ptr->stats.bearer_congs++; 1377 return PUSH_FAILED; 1378 } 1379 } 1380 } 1381 return PUSH_FINISHED; 1382 } 1383 1384 /* 1385 * push_queue(): push out the unsent messages of a link where 1386 * congestion has abated. Node is locked 1387 */ 1388 void tipc_link_push_queue(struct link *l_ptr) 1389 { 1390 u32 res; 1391 1392 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) 1393 return; 1394 1395 do { 1396 res = tipc_link_push_packet(l_ptr); 1397 } while (!res); 1398 1399 if (res == PUSH_FAILED) 1400 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 1401 } 1402 1403 static void link_reset_all(unsigned long addr) 1404 { 1405 struct tipc_node *n_ptr; 1406 char addr_string[16]; 1407 u32 i; 1408 1409 read_lock_bh(&tipc_net_lock); 1410 n_ptr = tipc_node_find((u32)addr); 1411 if (!n_ptr) { 1412 read_unlock_bh(&tipc_net_lock); 1413 return; /* node no longer exists */ 1414 } 1415 1416 tipc_node_lock(n_ptr); 1417 1418 warn("Resetting all links to %s\n", 1419 tipc_addr_string_fill(addr_string, n_ptr->addr)); 1420 1421 for (i = 0; i < MAX_BEARERS; i++) { 1422 if (n_ptr->links[i]) { 1423 link_print(n_ptr->links[i], "Resetting link\n"); 1424 tipc_link_reset(n_ptr->links[i]); 1425 } 1426 } 1427 1428 tipc_node_unlock(n_ptr); 1429 read_unlock_bh(&tipc_net_lock); 1430 } 1431 1432 static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf) 1433 { 1434 struct tipc_msg *msg = buf_msg(buf); 1435 1436 warn("Retransmission failure on link <%s>\n", l_ptr->name); 1437 1438 if (l_ptr->addr) { 1439 1440 /* Handle failure on standard link */ 1441 1442 link_print(l_ptr, "Resetting link\n"); 1443 tipc_link_reset(l_ptr); 1444 1445 } else { 1446 1447 /* Handle failure on broadcast link */ 1448 1449 struct tipc_node *n_ptr; 1450 char addr_string[16]; 1451 1452 info("Msg seq number: %u, ", msg_seqno(msg)); 1453 info("Outstanding acks: %lu\n", 1454 (unsigned long) TIPC_SKB_CB(buf)->handle); 1455 1456 n_ptr = tipc_bclink_retransmit_to(); 1457 tipc_node_lock(n_ptr); 1458 1459 tipc_addr_string_fill(addr_string, n_ptr->addr); 1460 info("Multicast link info for %s\n", addr_string); 1461 info("Supported: %d, ", n_ptr->bclink.supported); 1462 info("Acked: %u\n", n_ptr->bclink.acked); 1463 info("Last in: %u, ", n_ptr->bclink.last_in); 1464 info("Gap after: %u, ", n_ptr->bclink.gap_after); 1465 info("Gap to: %u\n", n_ptr->bclink.gap_to); 1466 info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync); 1467 1468 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr); 1469 1470 tipc_node_unlock(n_ptr); 1471 1472 l_ptr->stale_count = 0; 1473 } 1474 } 1475 1476 void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf, 1477 u32 retransmits) 1478 { 1479 struct tipc_msg *msg; 1480 1481 if (!buf) 1482 return; 1483 1484 msg = buf_msg(buf); 1485 1486 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { 1487 if (l_ptr->retransm_queue_size == 0) { 1488 l_ptr->retransm_queue_head = msg_seqno(msg); 1489 l_ptr->retransm_queue_size = retransmits; 1490 } else { 1491 err("Unexpected retransmit on link %s (qsize=%d)\n", 1492 l_ptr->name, l_ptr->retransm_queue_size); 1493 } 1494 return; 1495 } else { 1496 /* Detect repeated retransmit failures on uncongested bearer */ 1497 1498 if (l_ptr->last_retransmitted == msg_seqno(msg)) { 1499 if (++l_ptr->stale_count > 100) { 1500 link_retransmit_failure(l_ptr, buf); 1501 return; 1502 } 1503 } else { 1504 l_ptr->last_retransmitted = msg_seqno(msg); 1505 l_ptr->stale_count = 1; 1506 } 1507 } 1508 1509 while (retransmits && (buf != l_ptr->next_out) && buf) { 1510 msg = buf_msg(buf); 1511 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); 1512 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 1513 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 1514 buf = buf->next; 1515 retransmits--; 1516 l_ptr->stats.retransmitted++; 1517 } else { 1518 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 1519 l_ptr->stats.bearer_congs++; 1520 l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf)); 1521 l_ptr->retransm_queue_size = retransmits; 1522 return; 1523 } 1524 } 1525 1526 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0; 1527 } 1528 1529 /** 1530 * link_insert_deferred_queue - insert deferred messages back into receive chain 1531 */ 1532 1533 static struct sk_buff *link_insert_deferred_queue(struct link *l_ptr, 1534 struct sk_buff *buf) 1535 { 1536 u32 seq_no; 1537 1538 if (l_ptr->oldest_deferred_in == NULL) 1539 return buf; 1540 1541 seq_no = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); 1542 if (seq_no == mod(l_ptr->next_in_no)) { 1543 l_ptr->newest_deferred_in->next = buf; 1544 buf = l_ptr->oldest_deferred_in; 1545 l_ptr->oldest_deferred_in = NULL; 1546 l_ptr->deferred_inqueue_sz = 0; 1547 } 1548 return buf; 1549 } 1550 1551 /** 1552 * link_recv_buf_validate - validate basic format of received message 1553 * 1554 * This routine ensures a TIPC message has an acceptable header, and at least 1555 * as much data as the header indicates it should. The routine also ensures 1556 * that the entire message header is stored in the main fragment of the message 1557 * buffer, to simplify future access to message header fields. 1558 * 1559 * Note: Having extra info present in the message header or data areas is OK. 1560 * TIPC will ignore the excess, under the assumption that it is optional info 1561 * introduced by a later release of the protocol. 1562 */ 1563 1564 static int link_recv_buf_validate(struct sk_buff *buf) 1565 { 1566 static u32 min_data_hdr_size[8] = { 1567 SHORT_H_SIZE, MCAST_H_SIZE, LONG_H_SIZE, DIR_MSG_H_SIZE, 1568 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE 1569 }; 1570 1571 struct tipc_msg *msg; 1572 u32 tipc_hdr[2]; 1573 u32 size; 1574 u32 hdr_size; 1575 u32 min_hdr_size; 1576 1577 if (unlikely(buf->len < MIN_H_SIZE)) 1578 return 0; 1579 1580 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr); 1581 if (msg == NULL) 1582 return 0; 1583 1584 if (unlikely(msg_version(msg) != TIPC_VERSION)) 1585 return 0; 1586 1587 size = msg_size(msg); 1588 hdr_size = msg_hdr_sz(msg); 1589 min_hdr_size = msg_isdata(msg) ? 1590 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE; 1591 1592 if (unlikely((hdr_size < min_hdr_size) || 1593 (size < hdr_size) || 1594 (buf->len < size) || 1595 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE))) 1596 return 0; 1597 1598 return pskb_may_pull(buf, hdr_size); 1599 } 1600 1601 /** 1602 * tipc_recv_msg - process TIPC messages arriving from off-node 1603 * @head: pointer to message buffer chain 1604 * @tb_ptr: pointer to bearer message arrived on 1605 * 1606 * Invoked with no locks held. Bearer pointer must point to a valid bearer 1607 * structure (i.e. cannot be NULL), but bearer can be inactive. 1608 */ 1609 1610 void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr) 1611 { 1612 read_lock_bh(&tipc_net_lock); 1613 while (head) { 1614 struct tipc_node *n_ptr; 1615 struct link *l_ptr; 1616 struct sk_buff *crs; 1617 struct sk_buff *buf = head; 1618 struct tipc_msg *msg; 1619 u32 seq_no; 1620 u32 ackd; 1621 u32 released = 0; 1622 int type; 1623 1624 head = head->next; 1625 1626 /* Ensure bearer is still enabled */ 1627 1628 if (unlikely(!b_ptr->active)) 1629 goto cont; 1630 1631 /* Ensure message is well-formed */ 1632 1633 if (unlikely(!link_recv_buf_validate(buf))) 1634 goto cont; 1635 1636 /* Ensure message data is a single contiguous unit */ 1637 1638 if (unlikely(buf_linearize(buf))) 1639 goto cont; 1640 1641 /* Handle arrival of a non-unicast link message */ 1642 1643 msg = buf_msg(buf); 1644 1645 if (unlikely(msg_non_seq(msg))) { 1646 if (msg_user(msg) == LINK_CONFIG) 1647 tipc_disc_recv_msg(buf, b_ptr); 1648 else 1649 tipc_bclink_recv_pkt(buf); 1650 continue; 1651 } 1652 1653 if (unlikely(!msg_short(msg) && 1654 (msg_destnode(msg) != tipc_own_addr))) 1655 goto cont; 1656 1657 /* Discard non-routeable messages destined for another node */ 1658 1659 if (unlikely(!msg_isdata(msg) && 1660 (msg_destnode(msg) != tipc_own_addr))) { 1661 if ((msg_user(msg) != CONN_MANAGER) && 1662 (msg_user(msg) != MSG_FRAGMENTER)) 1663 goto cont; 1664 } 1665 1666 /* Locate neighboring node that sent message */ 1667 1668 n_ptr = tipc_node_find(msg_prevnode(msg)); 1669 if (unlikely(!n_ptr)) 1670 goto cont; 1671 tipc_node_lock(n_ptr); 1672 1673 /* Don't talk to neighbor during cleanup after last session */ 1674 1675 if (n_ptr->cleanup_required) { 1676 tipc_node_unlock(n_ptr); 1677 goto cont; 1678 } 1679 1680 /* Locate unicast link endpoint that should handle message */ 1681 1682 l_ptr = n_ptr->links[b_ptr->identity]; 1683 if (unlikely(!l_ptr)) { 1684 tipc_node_unlock(n_ptr); 1685 goto cont; 1686 } 1687 1688 /* Validate message sequence number info */ 1689 1690 seq_no = msg_seqno(msg); 1691 ackd = msg_ack(msg); 1692 1693 /* Release acked messages */ 1694 1695 if (less(n_ptr->bclink.acked, msg_bcast_ack(msg))) { 1696 if (tipc_node_is_up(n_ptr) && n_ptr->bclink.supported) 1697 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg)); 1698 } 1699 1700 crs = l_ptr->first_out; 1701 while ((crs != l_ptr->next_out) && 1702 less_eq(msg_seqno(buf_msg(crs)), ackd)) { 1703 struct sk_buff *next = crs->next; 1704 1705 buf_discard(crs); 1706 crs = next; 1707 released++; 1708 } 1709 if (released) { 1710 l_ptr->first_out = crs; 1711 l_ptr->out_queue_size -= released; 1712 } 1713 1714 /* Try sending any messages link endpoint has pending */ 1715 1716 if (unlikely(l_ptr->next_out)) 1717 tipc_link_push_queue(l_ptr); 1718 if (unlikely(!list_empty(&l_ptr->waiting_ports))) 1719 tipc_link_wakeup_ports(l_ptr, 0); 1720 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) { 1721 l_ptr->stats.sent_acks++; 1722 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); 1723 } 1724 1725 /* Now (finally!) process the incoming message */ 1726 1727 protocol_check: 1728 if (likely(link_working_working(l_ptr))) { 1729 if (likely(seq_no == mod(l_ptr->next_in_no))) { 1730 l_ptr->next_in_no++; 1731 if (unlikely(l_ptr->oldest_deferred_in)) 1732 head = link_insert_deferred_queue(l_ptr, 1733 head); 1734 if (likely(msg_is_dest(msg, tipc_own_addr))) { 1735 deliver: 1736 if (likely(msg_isdata(msg))) { 1737 tipc_node_unlock(n_ptr); 1738 tipc_port_recv_msg(buf); 1739 continue; 1740 } 1741 switch (msg_user(msg)) { 1742 case MSG_BUNDLER: 1743 l_ptr->stats.recv_bundles++; 1744 l_ptr->stats.recv_bundled += 1745 msg_msgcnt(msg); 1746 tipc_node_unlock(n_ptr); 1747 tipc_link_recv_bundle(buf); 1748 continue; 1749 case NAME_DISTRIBUTOR: 1750 tipc_node_unlock(n_ptr); 1751 tipc_named_recv(buf); 1752 continue; 1753 case CONN_MANAGER: 1754 tipc_node_unlock(n_ptr); 1755 tipc_port_recv_proto_msg(buf); 1756 continue; 1757 case MSG_FRAGMENTER: 1758 l_ptr->stats.recv_fragments++; 1759 if (tipc_link_recv_fragment(&l_ptr->defragm_buf, 1760 &buf, &msg)) { 1761 l_ptr->stats.recv_fragmented++; 1762 goto deliver; 1763 } 1764 break; 1765 case CHANGEOVER_PROTOCOL: 1766 type = msg_type(msg); 1767 if (link_recv_changeover_msg(&l_ptr, &buf)) { 1768 msg = buf_msg(buf); 1769 seq_no = msg_seqno(msg); 1770 if (type == ORIGINAL_MSG) 1771 goto deliver; 1772 goto protocol_check; 1773 } 1774 break; 1775 default: 1776 buf_discard(buf); 1777 buf = NULL; 1778 break; 1779 } 1780 } 1781 tipc_node_unlock(n_ptr); 1782 tipc_net_route_msg(buf); 1783 continue; 1784 } 1785 link_handle_out_of_seq_msg(l_ptr, buf); 1786 head = link_insert_deferred_queue(l_ptr, head); 1787 tipc_node_unlock(n_ptr); 1788 continue; 1789 } 1790 1791 if (msg_user(msg) == LINK_PROTOCOL) { 1792 link_recv_proto_msg(l_ptr, buf); 1793 head = link_insert_deferred_queue(l_ptr, head); 1794 tipc_node_unlock(n_ptr); 1795 continue; 1796 } 1797 link_state_event(l_ptr, TRAFFIC_MSG_EVT); 1798 1799 if (link_working_working(l_ptr)) { 1800 /* Re-insert in front of queue */ 1801 buf->next = head; 1802 head = buf; 1803 tipc_node_unlock(n_ptr); 1804 continue; 1805 } 1806 tipc_node_unlock(n_ptr); 1807 cont: 1808 buf_discard(buf); 1809 } 1810 read_unlock_bh(&tipc_net_lock); 1811 } 1812 1813 /* 1814 * link_defer_buf(): Sort a received out-of-sequence packet 1815 * into the deferred reception queue. 1816 * Returns the increase of the queue length,i.e. 0 or 1 1817 */ 1818 1819 u32 tipc_link_defer_pkt(struct sk_buff **head, 1820 struct sk_buff **tail, 1821 struct sk_buff *buf) 1822 { 1823 struct sk_buff *prev = NULL; 1824 struct sk_buff *crs = *head; 1825 u32 seq_no = msg_seqno(buf_msg(buf)); 1826 1827 buf->next = NULL; 1828 1829 /* Empty queue ? */ 1830 if (*head == NULL) { 1831 *head = *tail = buf; 1832 return 1; 1833 } 1834 1835 /* Last ? */ 1836 if (less(msg_seqno(buf_msg(*tail)), seq_no)) { 1837 (*tail)->next = buf; 1838 *tail = buf; 1839 return 1; 1840 } 1841 1842 /* Scan through queue and sort it in */ 1843 do { 1844 struct tipc_msg *msg = buf_msg(crs); 1845 1846 if (less(seq_no, msg_seqno(msg))) { 1847 buf->next = crs; 1848 if (prev) 1849 prev->next = buf; 1850 else 1851 *head = buf; 1852 return 1; 1853 } 1854 if (seq_no == msg_seqno(msg)) 1855 break; 1856 prev = crs; 1857 crs = crs->next; 1858 } while (crs); 1859 1860 /* Message is a duplicate of an existing message */ 1861 1862 buf_discard(buf); 1863 return 0; 1864 } 1865 1866 /** 1867 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet 1868 */ 1869 1870 static void link_handle_out_of_seq_msg(struct link *l_ptr, 1871 struct sk_buff *buf) 1872 { 1873 u32 seq_no = msg_seqno(buf_msg(buf)); 1874 1875 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) { 1876 link_recv_proto_msg(l_ptr, buf); 1877 return; 1878 } 1879 1880 /* Record OOS packet arrival (force mismatch on next timeout) */ 1881 1882 l_ptr->checkpoint--; 1883 1884 /* 1885 * Discard packet if a duplicate; otherwise add it to deferred queue 1886 * and notify peer of gap as per protocol specification 1887 */ 1888 1889 if (less(seq_no, mod(l_ptr->next_in_no))) { 1890 l_ptr->stats.duplicates++; 1891 buf_discard(buf); 1892 return; 1893 } 1894 1895 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in, 1896 &l_ptr->newest_deferred_in, buf)) { 1897 l_ptr->deferred_inqueue_sz++; 1898 l_ptr->stats.deferred_recv++; 1899 if ((l_ptr->deferred_inqueue_sz % 16) == 1) 1900 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); 1901 } else 1902 l_ptr->stats.duplicates++; 1903 } 1904 1905 /* 1906 * Send protocol message to the other endpoint. 1907 */ 1908 void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int probe_msg, 1909 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu) 1910 { 1911 struct sk_buff *buf = NULL; 1912 struct tipc_msg *msg = l_ptr->pmsg; 1913 u32 msg_size = sizeof(l_ptr->proto_msg); 1914 int r_flag; 1915 1916 if (link_blocked(l_ptr)) 1917 return; 1918 msg_set_type(msg, msg_typ); 1919 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane); 1920 msg_set_bcast_ack(msg, mod(l_ptr->owner->bclink.last_in)); 1921 msg_set_last_bcast(msg, tipc_bclink_get_last_sent()); 1922 1923 if (msg_typ == STATE_MSG) { 1924 u32 next_sent = mod(l_ptr->next_out_no); 1925 1926 if (!tipc_link_is_up(l_ptr)) 1927 return; 1928 if (l_ptr->next_out) 1929 next_sent = msg_seqno(buf_msg(l_ptr->next_out)); 1930 msg_set_next_sent(msg, next_sent); 1931 if (l_ptr->oldest_deferred_in) { 1932 u32 rec = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); 1933 gap = mod(rec - mod(l_ptr->next_in_no)); 1934 } 1935 msg_set_seq_gap(msg, gap); 1936 if (gap) 1937 l_ptr->stats.sent_nacks++; 1938 msg_set_link_tolerance(msg, tolerance); 1939 msg_set_linkprio(msg, priority); 1940 msg_set_max_pkt(msg, ack_mtu); 1941 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); 1942 msg_set_probe(msg, probe_msg != 0); 1943 if (probe_msg) { 1944 u32 mtu = l_ptr->max_pkt; 1945 1946 if ((mtu < l_ptr->max_pkt_target) && 1947 link_working_working(l_ptr) && 1948 l_ptr->fsm_msg_cnt) { 1949 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3; 1950 if (l_ptr->max_pkt_probes == 10) { 1951 l_ptr->max_pkt_target = (msg_size - 4); 1952 l_ptr->max_pkt_probes = 0; 1953 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3; 1954 } 1955 l_ptr->max_pkt_probes++; 1956 } 1957 1958 l_ptr->stats.sent_probes++; 1959 } 1960 l_ptr->stats.sent_states++; 1961 } else { /* RESET_MSG or ACTIVATE_MSG */ 1962 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1)); 1963 msg_set_seq_gap(msg, 0); 1964 msg_set_next_sent(msg, 1); 1965 msg_set_probe(msg, 0); 1966 msg_set_link_tolerance(msg, l_ptr->tolerance); 1967 msg_set_linkprio(msg, l_ptr->priority); 1968 msg_set_max_pkt(msg, l_ptr->max_pkt_target); 1969 } 1970 1971 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr)); 1972 msg_set_redundant_link(msg, r_flag); 1973 msg_set_linkprio(msg, l_ptr->priority); 1974 1975 /* Ensure sequence number will not fit : */ 1976 1977 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2))); 1978 1979 /* Congestion? */ 1980 1981 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { 1982 if (!l_ptr->proto_msg_queue) { 1983 l_ptr->proto_msg_queue = 1984 tipc_buf_acquire(sizeof(l_ptr->proto_msg)); 1985 } 1986 buf = l_ptr->proto_msg_queue; 1987 if (!buf) 1988 return; 1989 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); 1990 return; 1991 } 1992 1993 /* Message can be sent */ 1994 1995 buf = tipc_buf_acquire(msg_size); 1996 if (!buf) 1997 return; 1998 1999 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); 2000 msg_set_size(buf_msg(buf), msg_size); 2001 2002 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { 2003 l_ptr->unacked_window = 0; 2004 buf_discard(buf); 2005 return; 2006 } 2007 2008 /* New congestion */ 2009 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); 2010 l_ptr->proto_msg_queue = buf; 2011 l_ptr->stats.bearer_congs++; 2012 } 2013 2014 /* 2015 * Receive protocol message : 2016 * Note that network plane id propagates through the network, and may 2017 * change at any time. The node with lowest address rules 2018 */ 2019 2020 static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf) 2021 { 2022 u32 rec_gap = 0; 2023 u32 max_pkt_info; 2024 u32 max_pkt_ack; 2025 u32 msg_tol; 2026 struct tipc_msg *msg = buf_msg(buf); 2027 2028 if (link_blocked(l_ptr)) 2029 goto exit; 2030 2031 /* record unnumbered packet arrival (force mismatch on next timeout) */ 2032 2033 l_ptr->checkpoint--; 2034 2035 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg)) 2036 if (tipc_own_addr > msg_prevnode(msg)) 2037 l_ptr->b_ptr->net_plane = msg_net_plane(msg); 2038 2039 l_ptr->owner->permit_changeover = msg_redundant_link(msg); 2040 2041 switch (msg_type(msg)) { 2042 2043 case RESET_MSG: 2044 if (!link_working_unknown(l_ptr) && 2045 (l_ptr->peer_session != INVALID_SESSION)) { 2046 if (msg_session(msg) == l_ptr->peer_session) 2047 break; /* duplicate: ignore */ 2048 } 2049 /* fall thru' */ 2050 case ACTIVATE_MSG: 2051 /* Update link settings according other endpoint's values */ 2052 2053 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg)); 2054 2055 msg_tol = msg_link_tolerance(msg); 2056 if (msg_tol > l_ptr->tolerance) 2057 link_set_supervision_props(l_ptr, msg_tol); 2058 2059 if (msg_linkprio(msg) > l_ptr->priority) 2060 l_ptr->priority = msg_linkprio(msg); 2061 2062 max_pkt_info = msg_max_pkt(msg); 2063 if (max_pkt_info) { 2064 if (max_pkt_info < l_ptr->max_pkt_target) 2065 l_ptr->max_pkt_target = max_pkt_info; 2066 if (l_ptr->max_pkt > l_ptr->max_pkt_target) 2067 l_ptr->max_pkt = l_ptr->max_pkt_target; 2068 } else { 2069 l_ptr->max_pkt = l_ptr->max_pkt_target; 2070 } 2071 l_ptr->owner->bclink.supported = (max_pkt_info != 0); 2072 2073 link_state_event(l_ptr, msg_type(msg)); 2074 2075 l_ptr->peer_session = msg_session(msg); 2076 l_ptr->peer_bearer_id = msg_bearer_id(msg); 2077 2078 /* Synchronize broadcast sequence numbers */ 2079 if (!tipc_node_redundant_links(l_ptr->owner)) 2080 l_ptr->owner->bclink.last_in = mod(msg_last_bcast(msg)); 2081 break; 2082 case STATE_MSG: 2083 2084 msg_tol = msg_link_tolerance(msg); 2085 if (msg_tol) 2086 link_set_supervision_props(l_ptr, msg_tol); 2087 2088 if (msg_linkprio(msg) && 2089 (msg_linkprio(msg) != l_ptr->priority)) { 2090 warn("Resetting link <%s>, priority change %u->%u\n", 2091 l_ptr->name, l_ptr->priority, msg_linkprio(msg)); 2092 l_ptr->priority = msg_linkprio(msg); 2093 tipc_link_reset(l_ptr); /* Enforce change to take effect */ 2094 break; 2095 } 2096 link_state_event(l_ptr, TRAFFIC_MSG_EVT); 2097 l_ptr->stats.recv_states++; 2098 if (link_reset_unknown(l_ptr)) 2099 break; 2100 2101 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) { 2102 rec_gap = mod(msg_next_sent(msg) - 2103 mod(l_ptr->next_in_no)); 2104 } 2105 2106 max_pkt_ack = msg_max_pkt(msg); 2107 if (max_pkt_ack > l_ptr->max_pkt) { 2108 l_ptr->max_pkt = max_pkt_ack; 2109 l_ptr->max_pkt_probes = 0; 2110 } 2111 2112 max_pkt_ack = 0; 2113 if (msg_probe(msg)) { 2114 l_ptr->stats.recv_probes++; 2115 if (msg_size(msg) > sizeof(l_ptr->proto_msg)) 2116 max_pkt_ack = msg_size(msg); 2117 } 2118 2119 /* Protocol message before retransmits, reduce loss risk */ 2120 2121 tipc_bclink_check_gap(l_ptr->owner, msg_last_bcast(msg)); 2122 2123 if (rec_gap || (msg_probe(msg))) { 2124 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 2125 0, rec_gap, 0, 0, max_pkt_ack); 2126 } 2127 if (msg_seq_gap(msg)) { 2128 l_ptr->stats.recv_nacks++; 2129 tipc_link_retransmit(l_ptr, l_ptr->first_out, 2130 msg_seq_gap(msg)); 2131 } 2132 break; 2133 } 2134 exit: 2135 buf_discard(buf); 2136 } 2137 2138 2139 /* 2140 * tipc_link_tunnel(): Send one message via a link belonging to 2141 * another bearer. Owner node is locked. 2142 */ 2143 static void tipc_link_tunnel(struct link *l_ptr, 2144 struct tipc_msg *tunnel_hdr, 2145 struct tipc_msg *msg, 2146 u32 selector) 2147 { 2148 struct link *tunnel; 2149 struct sk_buff *buf; 2150 u32 length = msg_size(msg); 2151 2152 tunnel = l_ptr->owner->active_links[selector & 1]; 2153 if (!tipc_link_is_up(tunnel)) { 2154 warn("Link changeover error, " 2155 "tunnel link no longer available\n"); 2156 return; 2157 } 2158 msg_set_size(tunnel_hdr, length + INT_H_SIZE); 2159 buf = tipc_buf_acquire(length + INT_H_SIZE); 2160 if (!buf) { 2161 warn("Link changeover error, " 2162 "unable to send tunnel msg\n"); 2163 return; 2164 } 2165 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE); 2166 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length); 2167 tipc_link_send_buf(tunnel, buf); 2168 } 2169 2170 2171 2172 /* 2173 * changeover(): Send whole message queue via the remaining link 2174 * Owner node is locked. 2175 */ 2176 2177 void tipc_link_changeover(struct link *l_ptr) 2178 { 2179 u32 msgcount = l_ptr->out_queue_size; 2180 struct sk_buff *crs = l_ptr->first_out; 2181 struct link *tunnel = l_ptr->owner->active_links[0]; 2182 struct tipc_msg tunnel_hdr; 2183 int split_bundles; 2184 2185 if (!tunnel) 2186 return; 2187 2188 if (!l_ptr->owner->permit_changeover) { 2189 warn("Link changeover error, " 2190 "peer did not permit changeover\n"); 2191 return; 2192 } 2193 2194 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL, 2195 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr); 2196 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id); 2197 msg_set_msgcnt(&tunnel_hdr, msgcount); 2198 2199 if (!l_ptr->first_out) { 2200 struct sk_buff *buf; 2201 2202 buf = tipc_buf_acquire(INT_H_SIZE); 2203 if (buf) { 2204 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE); 2205 msg_set_size(&tunnel_hdr, INT_H_SIZE); 2206 tipc_link_send_buf(tunnel, buf); 2207 } else { 2208 warn("Link changeover error, " 2209 "unable to send changeover msg\n"); 2210 } 2211 return; 2212 } 2213 2214 split_bundles = (l_ptr->owner->active_links[0] != 2215 l_ptr->owner->active_links[1]); 2216 2217 while (crs) { 2218 struct tipc_msg *msg = buf_msg(crs); 2219 2220 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) { 2221 struct tipc_msg *m = msg_get_wrapped(msg); 2222 unchar *pos = (unchar *)m; 2223 2224 msgcount = msg_msgcnt(msg); 2225 while (msgcount--) { 2226 msg_set_seqno(m, msg_seqno(msg)); 2227 tipc_link_tunnel(l_ptr, &tunnel_hdr, m, 2228 msg_link_selector(m)); 2229 pos += align(msg_size(m)); 2230 m = (struct tipc_msg *)pos; 2231 } 2232 } else { 2233 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg, 2234 msg_link_selector(msg)); 2235 } 2236 crs = crs->next; 2237 } 2238 } 2239 2240 void tipc_link_send_duplicate(struct link *l_ptr, struct link *tunnel) 2241 { 2242 struct sk_buff *iter; 2243 struct tipc_msg tunnel_hdr; 2244 2245 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL, 2246 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr); 2247 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size); 2248 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id); 2249 iter = l_ptr->first_out; 2250 while (iter) { 2251 struct sk_buff *outbuf; 2252 struct tipc_msg *msg = buf_msg(iter); 2253 u32 length = msg_size(msg); 2254 2255 if (msg_user(msg) == MSG_BUNDLER) 2256 msg_set_type(msg, CLOSED_MSG); 2257 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */ 2258 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); 2259 msg_set_size(&tunnel_hdr, length + INT_H_SIZE); 2260 outbuf = tipc_buf_acquire(length + INT_H_SIZE); 2261 if (outbuf == NULL) { 2262 warn("Link changeover error, " 2263 "unable to send duplicate msg\n"); 2264 return; 2265 } 2266 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE); 2267 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data, 2268 length); 2269 tipc_link_send_buf(tunnel, outbuf); 2270 if (!tipc_link_is_up(l_ptr)) 2271 return; 2272 iter = iter->next; 2273 } 2274 } 2275 2276 2277 2278 /** 2279 * buf_extract - extracts embedded TIPC message from another message 2280 * @skb: encapsulating message buffer 2281 * @from_pos: offset to extract from 2282 * 2283 * Returns a new message buffer containing an embedded message. The 2284 * encapsulating message itself is left unchanged. 2285 */ 2286 2287 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos) 2288 { 2289 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos); 2290 u32 size = msg_size(msg); 2291 struct sk_buff *eb; 2292 2293 eb = tipc_buf_acquire(size); 2294 if (eb) 2295 skb_copy_to_linear_data(eb, msg, size); 2296 return eb; 2297 } 2298 2299 /* 2300 * link_recv_changeover_msg(): Receive tunneled packet sent 2301 * via other link. Node is locked. Return extracted buffer. 2302 */ 2303 2304 static int link_recv_changeover_msg(struct link **l_ptr, 2305 struct sk_buff **buf) 2306 { 2307 struct sk_buff *tunnel_buf = *buf; 2308 struct link *dest_link; 2309 struct tipc_msg *msg; 2310 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf); 2311 u32 msg_typ = msg_type(tunnel_msg); 2312 u32 msg_count = msg_msgcnt(tunnel_msg); 2313 2314 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)]; 2315 if (!dest_link) 2316 goto exit; 2317 if (dest_link == *l_ptr) { 2318 err("Unexpected changeover message on link <%s>\n", 2319 (*l_ptr)->name); 2320 goto exit; 2321 } 2322 *l_ptr = dest_link; 2323 msg = msg_get_wrapped(tunnel_msg); 2324 2325 if (msg_typ == DUPLICATE_MSG) { 2326 if (less(msg_seqno(msg), mod(dest_link->next_in_no))) 2327 goto exit; 2328 *buf = buf_extract(tunnel_buf, INT_H_SIZE); 2329 if (*buf == NULL) { 2330 warn("Link changeover error, duplicate msg dropped\n"); 2331 goto exit; 2332 } 2333 buf_discard(tunnel_buf); 2334 return 1; 2335 } 2336 2337 /* First original message ?: */ 2338 2339 if (tipc_link_is_up(dest_link)) { 2340 info("Resetting link <%s>, changeover initiated by peer\n", 2341 dest_link->name); 2342 tipc_link_reset(dest_link); 2343 dest_link->exp_msg_count = msg_count; 2344 if (!msg_count) 2345 goto exit; 2346 } else if (dest_link->exp_msg_count == START_CHANGEOVER) { 2347 dest_link->exp_msg_count = msg_count; 2348 if (!msg_count) 2349 goto exit; 2350 } 2351 2352 /* Receive original message */ 2353 2354 if (dest_link->exp_msg_count == 0) { 2355 warn("Link switchover error, " 2356 "got too many tunnelled messages\n"); 2357 goto exit; 2358 } 2359 dest_link->exp_msg_count--; 2360 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) { 2361 goto exit; 2362 } else { 2363 *buf = buf_extract(tunnel_buf, INT_H_SIZE); 2364 if (*buf != NULL) { 2365 buf_discard(tunnel_buf); 2366 return 1; 2367 } else { 2368 warn("Link changeover error, original msg dropped\n"); 2369 } 2370 } 2371 exit: 2372 *buf = NULL; 2373 buf_discard(tunnel_buf); 2374 return 0; 2375 } 2376 2377 /* 2378 * Bundler functionality: 2379 */ 2380 void tipc_link_recv_bundle(struct sk_buff *buf) 2381 { 2382 u32 msgcount = msg_msgcnt(buf_msg(buf)); 2383 u32 pos = INT_H_SIZE; 2384 struct sk_buff *obuf; 2385 2386 while (msgcount--) { 2387 obuf = buf_extract(buf, pos); 2388 if (obuf == NULL) { 2389 warn("Link unable to unbundle message(s)\n"); 2390 break; 2391 } 2392 pos += align(msg_size(buf_msg(obuf))); 2393 tipc_net_route_msg(obuf); 2394 } 2395 buf_discard(buf); 2396 } 2397 2398 /* 2399 * Fragmentation/defragmentation: 2400 */ 2401 2402 2403 /* 2404 * link_send_long_buf: Entry for buffers needing fragmentation. 2405 * The buffer is complete, inclusive total message length. 2406 * Returns user data length. 2407 */ 2408 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf) 2409 { 2410 struct tipc_msg *inmsg = buf_msg(buf); 2411 struct tipc_msg fragm_hdr; 2412 u32 insize = msg_size(inmsg); 2413 u32 dsz = msg_data_sz(inmsg); 2414 unchar *crs = buf->data; 2415 u32 rest = insize; 2416 u32 pack_sz = l_ptr->max_pkt; 2417 u32 fragm_sz = pack_sz - INT_H_SIZE; 2418 u32 fragm_no = 1; 2419 u32 destaddr; 2420 2421 if (msg_short(inmsg)) 2422 destaddr = l_ptr->addr; 2423 else 2424 destaddr = msg_destnode(inmsg); 2425 2426 /* Prepare reusable fragment header: */ 2427 2428 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT, 2429 INT_H_SIZE, destaddr); 2430 msg_set_link_selector(&fragm_hdr, msg_link_selector(inmsg)); 2431 msg_set_long_msgno(&fragm_hdr, mod(l_ptr->long_msg_seq_no++)); 2432 msg_set_fragm_no(&fragm_hdr, fragm_no); 2433 l_ptr->stats.sent_fragmented++; 2434 2435 /* Chop up message: */ 2436 2437 while (rest > 0) { 2438 struct sk_buff *fragm; 2439 2440 if (rest <= fragm_sz) { 2441 fragm_sz = rest; 2442 msg_set_type(&fragm_hdr, LAST_FRAGMENT); 2443 } 2444 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE); 2445 if (fragm == NULL) { 2446 warn("Link unable to fragment message\n"); 2447 dsz = -ENOMEM; 2448 goto exit; 2449 } 2450 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE); 2451 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE); 2452 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs, 2453 fragm_sz); 2454 /* Send queued messages first, if any: */ 2455 2456 l_ptr->stats.sent_fragments++; 2457 tipc_link_send_buf(l_ptr, fragm); 2458 if (!tipc_link_is_up(l_ptr)) 2459 return dsz; 2460 msg_set_fragm_no(&fragm_hdr, ++fragm_no); 2461 rest -= fragm_sz; 2462 crs += fragm_sz; 2463 msg_set_type(&fragm_hdr, FRAGMENT); 2464 } 2465 exit: 2466 buf_discard(buf); 2467 return dsz; 2468 } 2469 2470 /* 2471 * A pending message being re-assembled must store certain values 2472 * to handle subsequent fragments correctly. The following functions 2473 * help storing these values in unused, available fields in the 2474 * pending message. This makes dynamic memory allocation unecessary. 2475 */ 2476 2477 static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno) 2478 { 2479 msg_set_seqno(buf_msg(buf), seqno); 2480 } 2481 2482 static u32 get_fragm_size(struct sk_buff *buf) 2483 { 2484 return msg_ack(buf_msg(buf)); 2485 } 2486 2487 static void set_fragm_size(struct sk_buff *buf, u32 sz) 2488 { 2489 msg_set_ack(buf_msg(buf), sz); 2490 } 2491 2492 static u32 get_expected_frags(struct sk_buff *buf) 2493 { 2494 return msg_bcast_ack(buf_msg(buf)); 2495 } 2496 2497 static void set_expected_frags(struct sk_buff *buf, u32 exp) 2498 { 2499 msg_set_bcast_ack(buf_msg(buf), exp); 2500 } 2501 2502 static u32 get_timer_cnt(struct sk_buff *buf) 2503 { 2504 return msg_reroute_cnt(buf_msg(buf)); 2505 } 2506 2507 static void incr_timer_cnt(struct sk_buff *buf) 2508 { 2509 msg_incr_reroute_cnt(buf_msg(buf)); 2510 } 2511 2512 /* 2513 * tipc_link_recv_fragment(): Called with node lock on. Returns 2514 * the reassembled buffer if message is complete. 2515 */ 2516 int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb, 2517 struct tipc_msg **m) 2518 { 2519 struct sk_buff *prev = NULL; 2520 struct sk_buff *fbuf = *fb; 2521 struct tipc_msg *fragm = buf_msg(fbuf); 2522 struct sk_buff *pbuf = *pending; 2523 u32 long_msg_seq_no = msg_long_msgno(fragm); 2524 2525 *fb = NULL; 2526 2527 /* Is there an incomplete message waiting for this fragment? */ 2528 2529 while (pbuf && ((msg_seqno(buf_msg(pbuf)) != long_msg_seq_no) || 2530 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) { 2531 prev = pbuf; 2532 pbuf = pbuf->next; 2533 } 2534 2535 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) { 2536 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm); 2537 u32 msg_sz = msg_size(imsg); 2538 u32 fragm_sz = msg_data_sz(fragm); 2539 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz); 2540 u32 max = TIPC_MAX_USER_MSG_SIZE + LONG_H_SIZE; 2541 if (msg_type(imsg) == TIPC_MCAST_MSG) 2542 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE; 2543 if (msg_size(imsg) > max) { 2544 buf_discard(fbuf); 2545 return 0; 2546 } 2547 pbuf = tipc_buf_acquire(msg_size(imsg)); 2548 if (pbuf != NULL) { 2549 pbuf->next = *pending; 2550 *pending = pbuf; 2551 skb_copy_to_linear_data(pbuf, imsg, 2552 msg_data_sz(fragm)); 2553 /* Prepare buffer for subsequent fragments. */ 2554 2555 set_long_msg_seqno(pbuf, long_msg_seq_no); 2556 set_fragm_size(pbuf, fragm_sz); 2557 set_expected_frags(pbuf, exp_fragm_cnt - 1); 2558 } else { 2559 warn("Link unable to reassemble fragmented message\n"); 2560 } 2561 buf_discard(fbuf); 2562 return 0; 2563 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) { 2564 u32 dsz = msg_data_sz(fragm); 2565 u32 fsz = get_fragm_size(pbuf); 2566 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz); 2567 u32 exp_frags = get_expected_frags(pbuf) - 1; 2568 skb_copy_to_linear_data_offset(pbuf, crs, 2569 msg_data(fragm), dsz); 2570 buf_discard(fbuf); 2571 2572 /* Is message complete? */ 2573 2574 if (exp_frags == 0) { 2575 if (prev) 2576 prev->next = pbuf->next; 2577 else 2578 *pending = pbuf->next; 2579 msg_reset_reroute_cnt(buf_msg(pbuf)); 2580 *fb = pbuf; 2581 *m = buf_msg(pbuf); 2582 return 1; 2583 } 2584 set_expected_frags(pbuf, exp_frags); 2585 return 0; 2586 } 2587 buf_discard(fbuf); 2588 return 0; 2589 } 2590 2591 /** 2592 * link_check_defragm_bufs - flush stale incoming message fragments 2593 * @l_ptr: pointer to link 2594 */ 2595 2596 static void link_check_defragm_bufs(struct link *l_ptr) 2597 { 2598 struct sk_buff *prev = NULL; 2599 struct sk_buff *next = NULL; 2600 struct sk_buff *buf = l_ptr->defragm_buf; 2601 2602 if (!buf) 2603 return; 2604 if (!link_working_working(l_ptr)) 2605 return; 2606 while (buf) { 2607 u32 cnt = get_timer_cnt(buf); 2608 2609 next = buf->next; 2610 if (cnt < 4) { 2611 incr_timer_cnt(buf); 2612 prev = buf; 2613 } else { 2614 if (prev) 2615 prev->next = buf->next; 2616 else 2617 l_ptr->defragm_buf = buf->next; 2618 buf_discard(buf); 2619 } 2620 buf = next; 2621 } 2622 } 2623 2624 2625 2626 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance) 2627 { 2628 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL)) 2629 return; 2630 2631 l_ptr->tolerance = tolerance; 2632 l_ptr->continuity_interval = 2633 ((tolerance / 4) > 500) ? 500 : tolerance / 4; 2634 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4); 2635 } 2636 2637 2638 void tipc_link_set_queue_limits(struct link *l_ptr, u32 window) 2639 { 2640 /* Data messages from this node, inclusive FIRST_FRAGM */ 2641 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window; 2642 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4; 2643 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5; 2644 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6; 2645 /* Transiting data messages,inclusive FIRST_FRAGM */ 2646 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300; 2647 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600; 2648 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900; 2649 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200; 2650 l_ptr->queue_limit[CONN_MANAGER] = 1200; 2651 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500; 2652 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000; 2653 /* FRAGMENT and LAST_FRAGMENT packets */ 2654 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000; 2655 } 2656 2657 /** 2658 * link_find_link - locate link by name 2659 * @name - ptr to link name string 2660 * @node - ptr to area to be filled with ptr to associated node 2661 * 2662 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted; 2663 * this also prevents link deletion. 2664 * 2665 * Returns pointer to link (or 0 if invalid link name). 2666 */ 2667 2668 static struct link *link_find_link(const char *name, struct tipc_node **node) 2669 { 2670 struct link_name link_name_parts; 2671 struct tipc_bearer *b_ptr; 2672 struct link *l_ptr; 2673 2674 if (!link_name_validate(name, &link_name_parts)) 2675 return NULL; 2676 2677 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local); 2678 if (!b_ptr) 2679 return NULL; 2680 2681 *node = tipc_node_find(link_name_parts.addr_peer); 2682 if (!*node) 2683 return NULL; 2684 2685 l_ptr = (*node)->links[b_ptr->identity]; 2686 if (!l_ptr || strcmp(l_ptr->name, name)) 2687 return NULL; 2688 2689 return l_ptr; 2690 } 2691 2692 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, 2693 u16 cmd) 2694 { 2695 struct tipc_link_config *args; 2696 u32 new_value; 2697 struct link *l_ptr; 2698 struct tipc_node *node; 2699 int res; 2700 2701 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG)) 2702 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 2703 2704 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area); 2705 new_value = ntohl(args->value); 2706 2707 if (!strcmp(args->name, tipc_bclink_name)) { 2708 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) && 2709 (tipc_bclink_set_queue_limits(new_value) == 0)) 2710 return tipc_cfg_reply_none(); 2711 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED 2712 " (cannot change setting on broadcast link)"); 2713 } 2714 2715 read_lock_bh(&tipc_net_lock); 2716 l_ptr = link_find_link(args->name, &node); 2717 if (!l_ptr) { 2718 read_unlock_bh(&tipc_net_lock); 2719 return tipc_cfg_reply_error_string("link not found"); 2720 } 2721 2722 tipc_node_lock(node); 2723 res = -EINVAL; 2724 switch (cmd) { 2725 case TIPC_CMD_SET_LINK_TOL: 2726 if ((new_value >= TIPC_MIN_LINK_TOL) && 2727 (new_value <= TIPC_MAX_LINK_TOL)) { 2728 link_set_supervision_props(l_ptr, new_value); 2729 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 2730 0, 0, new_value, 0, 0); 2731 res = 0; 2732 } 2733 break; 2734 case TIPC_CMD_SET_LINK_PRI: 2735 if ((new_value >= TIPC_MIN_LINK_PRI) && 2736 (new_value <= TIPC_MAX_LINK_PRI)) { 2737 l_ptr->priority = new_value; 2738 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 2739 0, 0, 0, new_value, 0); 2740 res = 0; 2741 } 2742 break; 2743 case TIPC_CMD_SET_LINK_WINDOW: 2744 if ((new_value >= TIPC_MIN_LINK_WIN) && 2745 (new_value <= TIPC_MAX_LINK_WIN)) { 2746 tipc_link_set_queue_limits(l_ptr, new_value); 2747 res = 0; 2748 } 2749 break; 2750 } 2751 tipc_node_unlock(node); 2752 2753 read_unlock_bh(&tipc_net_lock); 2754 if (res) 2755 return tipc_cfg_reply_error_string("cannot change link setting"); 2756 2757 return tipc_cfg_reply_none(); 2758 } 2759 2760 /** 2761 * link_reset_statistics - reset link statistics 2762 * @l_ptr: pointer to link 2763 */ 2764 2765 static void link_reset_statistics(struct link *l_ptr) 2766 { 2767 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats)); 2768 l_ptr->stats.sent_info = l_ptr->next_out_no; 2769 l_ptr->stats.recv_info = l_ptr->next_in_no; 2770 } 2771 2772 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space) 2773 { 2774 char *link_name; 2775 struct link *l_ptr; 2776 struct tipc_node *node; 2777 2778 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME)) 2779 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 2780 2781 link_name = (char *)TLV_DATA(req_tlv_area); 2782 if (!strcmp(link_name, tipc_bclink_name)) { 2783 if (tipc_bclink_reset_stats()) 2784 return tipc_cfg_reply_error_string("link not found"); 2785 return tipc_cfg_reply_none(); 2786 } 2787 2788 read_lock_bh(&tipc_net_lock); 2789 l_ptr = link_find_link(link_name, &node); 2790 if (!l_ptr) { 2791 read_unlock_bh(&tipc_net_lock); 2792 return tipc_cfg_reply_error_string("link not found"); 2793 } 2794 2795 tipc_node_lock(node); 2796 link_reset_statistics(l_ptr); 2797 tipc_node_unlock(node); 2798 read_unlock_bh(&tipc_net_lock); 2799 return tipc_cfg_reply_none(); 2800 } 2801 2802 /** 2803 * percent - convert count to a percentage of total (rounding up or down) 2804 */ 2805 2806 static u32 percent(u32 count, u32 total) 2807 { 2808 return (count * 100 + (total / 2)) / total; 2809 } 2810 2811 /** 2812 * tipc_link_stats - print link statistics 2813 * @name: link name 2814 * @buf: print buffer area 2815 * @buf_size: size of print buffer area 2816 * 2817 * Returns length of print buffer data string (or 0 if error) 2818 */ 2819 2820 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size) 2821 { 2822 struct print_buf pb; 2823 struct link *l_ptr; 2824 struct tipc_node *node; 2825 char *status; 2826 u32 profile_total = 0; 2827 2828 if (!strcmp(name, tipc_bclink_name)) 2829 return tipc_bclink_stats(buf, buf_size); 2830 2831 tipc_printbuf_init(&pb, buf, buf_size); 2832 2833 read_lock_bh(&tipc_net_lock); 2834 l_ptr = link_find_link(name, &node); 2835 if (!l_ptr) { 2836 read_unlock_bh(&tipc_net_lock); 2837 return 0; 2838 } 2839 tipc_node_lock(node); 2840 2841 if (tipc_link_is_active(l_ptr)) 2842 status = "ACTIVE"; 2843 else if (tipc_link_is_up(l_ptr)) 2844 status = "STANDBY"; 2845 else 2846 status = "DEFUNCT"; 2847 tipc_printf(&pb, "Link <%s>\n" 2848 " %s MTU:%u Priority:%u Tolerance:%u ms" 2849 " Window:%u packets\n", 2850 l_ptr->name, status, l_ptr->max_pkt, 2851 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]); 2852 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n", 2853 l_ptr->next_in_no - l_ptr->stats.recv_info, 2854 l_ptr->stats.recv_fragments, 2855 l_ptr->stats.recv_fragmented, 2856 l_ptr->stats.recv_bundles, 2857 l_ptr->stats.recv_bundled); 2858 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n", 2859 l_ptr->next_out_no - l_ptr->stats.sent_info, 2860 l_ptr->stats.sent_fragments, 2861 l_ptr->stats.sent_fragmented, 2862 l_ptr->stats.sent_bundles, 2863 l_ptr->stats.sent_bundled); 2864 profile_total = l_ptr->stats.msg_length_counts; 2865 if (!profile_total) 2866 profile_total = 1; 2867 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n" 2868 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% " 2869 "-16354:%u%% -32768:%u%% -66000:%u%%\n", 2870 l_ptr->stats.msg_length_counts, 2871 l_ptr->stats.msg_lengths_total / profile_total, 2872 percent(l_ptr->stats.msg_length_profile[0], profile_total), 2873 percent(l_ptr->stats.msg_length_profile[1], profile_total), 2874 percent(l_ptr->stats.msg_length_profile[2], profile_total), 2875 percent(l_ptr->stats.msg_length_profile[3], profile_total), 2876 percent(l_ptr->stats.msg_length_profile[4], profile_total), 2877 percent(l_ptr->stats.msg_length_profile[5], profile_total), 2878 percent(l_ptr->stats.msg_length_profile[6], profile_total)); 2879 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n", 2880 l_ptr->stats.recv_states, 2881 l_ptr->stats.recv_probes, 2882 l_ptr->stats.recv_nacks, 2883 l_ptr->stats.deferred_recv, 2884 l_ptr->stats.duplicates); 2885 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n", 2886 l_ptr->stats.sent_states, 2887 l_ptr->stats.sent_probes, 2888 l_ptr->stats.sent_nacks, 2889 l_ptr->stats.sent_acks, 2890 l_ptr->stats.retransmitted); 2891 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n", 2892 l_ptr->stats.bearer_congs, 2893 l_ptr->stats.link_congs, 2894 l_ptr->stats.max_queue_sz, 2895 l_ptr->stats.queue_sz_counts 2896 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts) 2897 : 0); 2898 2899 tipc_node_unlock(node); 2900 read_unlock_bh(&tipc_net_lock); 2901 return tipc_printbuf_validate(&pb); 2902 } 2903 2904 #define MAX_LINK_STATS_INFO 2000 2905 2906 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space) 2907 { 2908 struct sk_buff *buf; 2909 struct tlv_desc *rep_tlv; 2910 int str_len; 2911 2912 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME)) 2913 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 2914 2915 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO)); 2916 if (!buf) 2917 return NULL; 2918 2919 rep_tlv = (struct tlv_desc *)buf->data; 2920 2921 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area), 2922 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO); 2923 if (!str_len) { 2924 buf_discard(buf); 2925 return tipc_cfg_reply_error_string("link not found"); 2926 } 2927 2928 skb_put(buf, TLV_SPACE(str_len)); 2929 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len); 2930 2931 return buf; 2932 } 2933 2934 /** 2935 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination 2936 * @dest: network address of destination node 2937 * @selector: used to select from set of active links 2938 * 2939 * If no active link can be found, uses default maximum packet size. 2940 */ 2941 2942 u32 tipc_link_get_max_pkt(u32 dest, u32 selector) 2943 { 2944 struct tipc_node *n_ptr; 2945 struct link *l_ptr; 2946 u32 res = MAX_PKT_DEFAULT; 2947 2948 if (dest == tipc_own_addr) 2949 return MAX_MSG_SIZE; 2950 2951 read_lock_bh(&tipc_net_lock); 2952 n_ptr = tipc_node_find(dest); 2953 if (n_ptr) { 2954 tipc_node_lock(n_ptr); 2955 l_ptr = n_ptr->active_links[selector & 1]; 2956 if (l_ptr) 2957 res = l_ptr->max_pkt; 2958 tipc_node_unlock(n_ptr); 2959 } 2960 read_unlock_bh(&tipc_net_lock); 2961 return res; 2962 } 2963 2964 static void link_print(struct link *l_ptr, const char *str) 2965 { 2966 char print_area[256]; 2967 struct print_buf pb; 2968 struct print_buf *buf = &pb; 2969 2970 tipc_printbuf_init(buf, print_area, sizeof(print_area)); 2971 2972 tipc_printf(buf, str); 2973 tipc_printf(buf, "Link %x<%s>:", 2974 l_ptr->addr, l_ptr->b_ptr->name); 2975 2976 #ifdef CONFIG_TIPC_DEBUG 2977 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr)) 2978 goto print_state; 2979 2980 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no)); 2981 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no)); 2982 tipc_printf(buf, "SQUE"); 2983 if (l_ptr->first_out) { 2984 tipc_printf(buf, "[%u..", msg_seqno(buf_msg(l_ptr->first_out))); 2985 if (l_ptr->next_out) 2986 tipc_printf(buf, "%u..", 2987 msg_seqno(buf_msg(l_ptr->next_out))); 2988 tipc_printf(buf, "%u]", msg_seqno(buf_msg(l_ptr->last_out))); 2989 if ((mod(msg_seqno(buf_msg(l_ptr->last_out)) - 2990 msg_seqno(buf_msg(l_ptr->first_out))) 2991 != (l_ptr->out_queue_size - 1)) || 2992 (l_ptr->last_out->next != NULL)) { 2993 tipc_printf(buf, "\nSend queue inconsistency\n"); 2994 tipc_printf(buf, "first_out= %p ", l_ptr->first_out); 2995 tipc_printf(buf, "next_out= %p ", l_ptr->next_out); 2996 tipc_printf(buf, "last_out= %p ", l_ptr->last_out); 2997 } 2998 } else 2999 tipc_printf(buf, "[]"); 3000 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size); 3001 if (l_ptr->oldest_deferred_in) { 3002 u32 o = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); 3003 u32 n = msg_seqno(buf_msg(l_ptr->newest_deferred_in)); 3004 tipc_printf(buf, ":RQUE[%u..%u]", o, n); 3005 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) { 3006 tipc_printf(buf, ":RQSIZ(%u)", 3007 l_ptr->deferred_inqueue_sz); 3008 } 3009 } 3010 print_state: 3011 #endif 3012 3013 if (link_working_unknown(l_ptr)) 3014 tipc_printf(buf, ":WU"); 3015 else if (link_reset_reset(l_ptr)) 3016 tipc_printf(buf, ":RR"); 3017 else if (link_reset_unknown(l_ptr)) 3018 tipc_printf(buf, ":RU"); 3019 else if (link_working_working(l_ptr)) 3020 tipc_printf(buf, ":WW"); 3021 tipc_printf(buf, "\n"); 3022 3023 tipc_printbuf_validate(buf); 3024 info("%s", print_area); 3025 } 3026 3027