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