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