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