1 /* 2 * net/tipc/link.c: TIPC link code 3 * 4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB 5 * Copyright (c) 2004-2007, 2010-2013, 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 "subscr.h" 39 #include "link.h" 40 #include "bcast.h" 41 #include "socket.h" 42 #include "name_distr.h" 43 #include "discover.h" 44 #include "netlink.h" 45 #include "monitor.h" 46 47 #include <linux/pkt_sched.h> 48 49 struct tipc_stats { 50 u32 sent_pkts; 51 u32 recv_pkts; 52 u32 sent_states; 53 u32 recv_states; 54 u32 sent_probes; 55 u32 recv_probes; 56 u32 sent_nacks; 57 u32 recv_nacks; 58 u32 sent_acks; 59 u32 sent_bundled; 60 u32 sent_bundles; 61 u32 recv_bundled; 62 u32 recv_bundles; 63 u32 retransmitted; 64 u32 sent_fragmented; 65 u32 sent_fragments; 66 u32 recv_fragmented; 67 u32 recv_fragments; 68 u32 link_congs; /* # port sends blocked by congestion */ 69 u32 deferred_recv; 70 u32 duplicates; 71 u32 max_queue_sz; /* send queue size high water mark */ 72 u32 accu_queue_sz; /* used for send queue size profiling */ 73 u32 queue_sz_counts; /* used for send queue size profiling */ 74 u32 msg_length_counts; /* used for message length profiling */ 75 u32 msg_lengths_total; /* used for message length profiling */ 76 u32 msg_length_profile[7]; /* used for msg. length profiling */ 77 }; 78 79 /** 80 * struct tipc_link - TIPC link data structure 81 * @addr: network address of link's peer node 82 * @name: link name character string 83 * @media_addr: media address to use when sending messages over link 84 * @timer: link timer 85 * @net: pointer to namespace struct 86 * @refcnt: reference counter for permanent references (owner node & timer) 87 * @peer_session: link session # being used by peer end of link 88 * @peer_bearer_id: bearer id used by link's peer endpoint 89 * @bearer_id: local bearer id used by link 90 * @tolerance: minimum link continuity loss needed to reset link [in ms] 91 * @abort_limit: # of unacknowledged continuity probes needed to reset link 92 * @state: current state of link FSM 93 * @peer_caps: bitmap describing capabilities of peer node 94 * @silent_intv_cnt: # of timer intervals without any reception from peer 95 * @proto_msg: template for control messages generated by link 96 * @pmsg: convenience pointer to "proto_msg" field 97 * @priority: current link priority 98 * @net_plane: current link network plane ('A' through 'H') 99 * @mon_state: cookie with information needed by link monitor 100 * @backlog_limit: backlog queue congestion thresholds (indexed by importance) 101 * @exp_msg_count: # of tunnelled messages expected during link changeover 102 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset 103 * @mtu: current maximum packet size for this link 104 * @advertised_mtu: advertised own mtu when link is being established 105 * @transmitq: queue for sent, non-acked messages 106 * @backlogq: queue for messages waiting to be sent 107 * @snt_nxt: next sequence number to use for outbound messages 108 * @last_retransmitted: sequence number of most recently retransmitted message 109 * @stale_cnt: counter for number of identical retransmit attempts 110 * @stale_limit: time when repeated identical retransmits must force link reset 111 * @ackers: # of peers that needs to ack each packet before it can be released 112 * @acked: # last packet acked by a certain peer. Used for broadcast. 113 * @rcv_nxt: next sequence number to expect for inbound messages 114 * @deferred_queue: deferred queue saved OOS b'cast message received from node 115 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 116 * @inputq: buffer queue for messages to be delivered upwards 117 * @namedq: buffer queue for name table messages to be delivered upwards 118 * @next_out: ptr to first unsent outbound message in queue 119 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate 120 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 121 * @reasm_buf: head of partially reassembled inbound message fragments 122 * @bc_rcvr: marks that this is a broadcast receiver link 123 * @stats: collects statistics regarding link activity 124 */ 125 struct tipc_link { 126 u32 addr; 127 char name[TIPC_MAX_LINK_NAME]; 128 struct net *net; 129 130 /* Management and link supervision data */ 131 u16 peer_session; 132 u16 session; 133 u16 snd_nxt_state; 134 u16 rcv_nxt_state; 135 u32 peer_bearer_id; 136 u32 bearer_id; 137 u32 tolerance; 138 u32 abort_limit; 139 u32 state; 140 u16 peer_caps; 141 bool in_session; 142 bool active; 143 u32 silent_intv_cnt; 144 char if_name[TIPC_MAX_IF_NAME]; 145 u32 priority; 146 char net_plane; 147 struct tipc_mon_state mon_state; 148 u16 rst_cnt; 149 150 /* Failover/synch */ 151 u16 drop_point; 152 struct sk_buff *failover_reasm_skb; 153 154 /* Max packet negotiation */ 155 u16 mtu; 156 u16 advertised_mtu; 157 158 /* Sending */ 159 struct sk_buff_head transmq; 160 struct sk_buff_head backlogq; 161 struct { 162 u16 len; 163 u16 limit; 164 } backlog[5]; 165 u16 snd_nxt; 166 u16 last_retransm; 167 u16 window; 168 u16 stale_cnt; 169 unsigned long stale_limit; 170 171 /* Reception */ 172 u16 rcv_nxt; 173 u32 rcv_unacked; 174 struct sk_buff_head deferdq; 175 struct sk_buff_head *inputq; 176 struct sk_buff_head *namedq; 177 178 /* Congestion handling */ 179 struct sk_buff_head wakeupq; 180 181 /* Fragmentation/reassembly */ 182 struct sk_buff *reasm_buf; 183 184 /* Broadcast */ 185 u16 ackers; 186 u16 acked; 187 struct tipc_link *bc_rcvlink; 188 struct tipc_link *bc_sndlink; 189 unsigned long prev_retr; 190 u16 prev_from; 191 u16 prev_to; 192 u8 nack_state; 193 bool bc_peer_is_up; 194 195 /* Statistics */ 196 struct tipc_stats stats; 197 }; 198 199 /* 200 * Error message prefixes 201 */ 202 static const char *link_co_err = "Link tunneling error, "; 203 static const char *link_rst_msg = "Resetting link "; 204 205 /* Send states for broadcast NACKs 206 */ 207 enum { 208 BC_NACK_SND_CONDITIONAL, 209 BC_NACK_SND_UNCONDITIONAL, 210 BC_NACK_SND_SUPPRESS, 211 }; 212 213 #define TIPC_BC_RETR_LIMIT 10 /* [ms] */ 214 215 /* 216 * Interval between NACKs when packets arrive out of order 217 */ 218 #define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2) 219 220 /* Link FSM states: 221 */ 222 enum { 223 LINK_ESTABLISHED = 0xe, 224 LINK_ESTABLISHING = 0xe << 4, 225 LINK_RESET = 0x1 << 8, 226 LINK_RESETTING = 0x2 << 12, 227 LINK_PEER_RESET = 0xd << 16, 228 LINK_FAILINGOVER = 0xf << 20, 229 LINK_SYNCHING = 0xc << 24 230 }; 231 232 /* Link FSM state checking routines 233 */ 234 static int link_is_up(struct tipc_link *l) 235 { 236 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING); 237 } 238 239 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, 240 struct sk_buff_head *xmitq); 241 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, 242 bool probe_reply, u16 rcvgap, 243 int tolerance, int priority, 244 struct sk_buff_head *xmitq); 245 static void link_print(struct tipc_link *l, const char *str); 246 static int tipc_link_build_nack_msg(struct tipc_link *l, 247 struct sk_buff_head *xmitq); 248 static void tipc_link_build_bc_init_msg(struct tipc_link *l, 249 struct sk_buff_head *xmitq); 250 static bool tipc_link_release_pkts(struct tipc_link *l, u16 to); 251 252 /* 253 * Simple non-static link routines (i.e. referenced outside this file) 254 */ 255 bool tipc_link_is_up(struct tipc_link *l) 256 { 257 return link_is_up(l); 258 } 259 260 bool tipc_link_peer_is_down(struct tipc_link *l) 261 { 262 return l->state == LINK_PEER_RESET; 263 } 264 265 bool tipc_link_is_reset(struct tipc_link *l) 266 { 267 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING); 268 } 269 270 bool tipc_link_is_establishing(struct tipc_link *l) 271 { 272 return l->state == LINK_ESTABLISHING; 273 } 274 275 bool tipc_link_is_synching(struct tipc_link *l) 276 { 277 return l->state == LINK_SYNCHING; 278 } 279 280 bool tipc_link_is_failingover(struct tipc_link *l) 281 { 282 return l->state == LINK_FAILINGOVER; 283 } 284 285 bool tipc_link_is_blocked(struct tipc_link *l) 286 { 287 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER); 288 } 289 290 static bool link_is_bc_sndlink(struct tipc_link *l) 291 { 292 return !l->bc_sndlink; 293 } 294 295 static bool link_is_bc_rcvlink(struct tipc_link *l) 296 { 297 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l)); 298 } 299 300 void tipc_link_set_active(struct tipc_link *l, bool active) 301 { 302 l->active = active; 303 } 304 305 u32 tipc_link_id(struct tipc_link *l) 306 { 307 return l->peer_bearer_id << 16 | l->bearer_id; 308 } 309 310 int tipc_link_window(struct tipc_link *l) 311 { 312 return l->window; 313 } 314 315 int tipc_link_prio(struct tipc_link *l) 316 { 317 return l->priority; 318 } 319 320 unsigned long tipc_link_tolerance(struct tipc_link *l) 321 { 322 return l->tolerance; 323 } 324 325 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l) 326 { 327 return l->inputq; 328 } 329 330 char tipc_link_plane(struct tipc_link *l) 331 { 332 return l->net_plane; 333 } 334 335 void tipc_link_update_caps(struct tipc_link *l, u16 capabilities) 336 { 337 l->peer_caps = capabilities; 338 } 339 340 void tipc_link_add_bc_peer(struct tipc_link *snd_l, 341 struct tipc_link *uc_l, 342 struct sk_buff_head *xmitq) 343 { 344 struct tipc_link *rcv_l = uc_l->bc_rcvlink; 345 346 snd_l->ackers++; 347 rcv_l->acked = snd_l->snd_nxt - 1; 348 snd_l->state = LINK_ESTABLISHED; 349 tipc_link_build_bc_init_msg(uc_l, xmitq); 350 } 351 352 void tipc_link_remove_bc_peer(struct tipc_link *snd_l, 353 struct tipc_link *rcv_l, 354 struct sk_buff_head *xmitq) 355 { 356 u16 ack = snd_l->snd_nxt - 1; 357 358 snd_l->ackers--; 359 rcv_l->bc_peer_is_up = true; 360 rcv_l->state = LINK_ESTABLISHED; 361 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq); 362 tipc_link_reset(rcv_l); 363 rcv_l->state = LINK_RESET; 364 if (!snd_l->ackers) { 365 tipc_link_reset(snd_l); 366 snd_l->state = LINK_RESET; 367 __skb_queue_purge(xmitq); 368 } 369 } 370 371 int tipc_link_bc_peers(struct tipc_link *l) 372 { 373 return l->ackers; 374 } 375 376 static u16 link_bc_rcv_gap(struct tipc_link *l) 377 { 378 struct sk_buff *skb = skb_peek(&l->deferdq); 379 u16 gap = 0; 380 381 if (more(l->snd_nxt, l->rcv_nxt)) 382 gap = l->snd_nxt - l->rcv_nxt; 383 if (skb) 384 gap = buf_seqno(skb) - l->rcv_nxt; 385 return gap; 386 } 387 388 void tipc_link_set_mtu(struct tipc_link *l, int mtu) 389 { 390 l->mtu = mtu; 391 } 392 393 int tipc_link_mtu(struct tipc_link *l) 394 { 395 return l->mtu; 396 } 397 398 u16 tipc_link_rcv_nxt(struct tipc_link *l) 399 { 400 return l->rcv_nxt; 401 } 402 403 u16 tipc_link_acked(struct tipc_link *l) 404 { 405 return l->acked; 406 } 407 408 char *tipc_link_name(struct tipc_link *l) 409 { 410 return l->name; 411 } 412 413 u32 tipc_link_state(struct tipc_link *l) 414 { 415 return l->state; 416 } 417 418 /** 419 * tipc_link_create - create a new link 420 * @n: pointer to associated node 421 * @if_name: associated interface name 422 * @bearer_id: id (index) of associated bearer 423 * @tolerance: link tolerance to be used by link 424 * @net_plane: network plane (A,B,c..) this link belongs to 425 * @mtu: mtu to be advertised by link 426 * @priority: priority to be used by link 427 * @window: send window to be used by link 428 * @session: session to be used by link 429 * @ownnode: identity of own node 430 * @peer: node id of peer node 431 * @peer_caps: bitmap describing peer node capabilities 432 * @bc_sndlink: the namespace global link used for broadcast sending 433 * @bc_rcvlink: the peer specific link used for broadcast reception 434 * @inputq: queue to put messages ready for delivery 435 * @namedq: queue to put binding table update messages ready for delivery 436 * @link: return value, pointer to put the created link 437 * 438 * Returns true if link was created, otherwise false 439 */ 440 bool tipc_link_create(struct net *net, char *if_name, int bearer_id, 441 int tolerance, char net_plane, u32 mtu, int priority, 442 int window, u32 session, u32 self, 443 u32 peer, u8 *peer_id, u16 peer_caps, 444 struct tipc_link *bc_sndlink, 445 struct tipc_link *bc_rcvlink, 446 struct sk_buff_head *inputq, 447 struct sk_buff_head *namedq, 448 struct tipc_link **link) 449 { 450 char peer_str[NODE_ID_STR_LEN] = {0,}; 451 char self_str[NODE_ID_STR_LEN] = {0,}; 452 struct tipc_link *l; 453 454 l = kzalloc(sizeof(*l), GFP_ATOMIC); 455 if (!l) 456 return false; 457 *link = l; 458 l->session = session; 459 460 /* Set link name for unicast links only */ 461 if (peer_id) { 462 tipc_nodeid2string(self_str, tipc_own_id(net)); 463 if (strlen(self_str) > 16) 464 sprintf(self_str, "%x", self); 465 tipc_nodeid2string(peer_str, peer_id); 466 if (strlen(peer_str) > 16) 467 sprintf(peer_str, "%x", peer); 468 } 469 /* Peer i/f name will be completed by reset/activate message */ 470 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown", 471 self_str, if_name, peer_str); 472 473 strcpy(l->if_name, if_name); 474 l->addr = peer; 475 l->peer_caps = peer_caps; 476 l->net = net; 477 l->in_session = false; 478 l->bearer_id = bearer_id; 479 l->tolerance = tolerance; 480 if (bc_rcvlink) 481 bc_rcvlink->tolerance = tolerance; 482 l->net_plane = net_plane; 483 l->advertised_mtu = mtu; 484 l->mtu = mtu; 485 l->priority = priority; 486 tipc_link_set_queue_limits(l, window); 487 l->ackers = 1; 488 l->bc_sndlink = bc_sndlink; 489 l->bc_rcvlink = bc_rcvlink; 490 l->inputq = inputq; 491 l->namedq = namedq; 492 l->state = LINK_RESETTING; 493 __skb_queue_head_init(&l->transmq); 494 __skb_queue_head_init(&l->backlogq); 495 __skb_queue_head_init(&l->deferdq); 496 skb_queue_head_init(&l->wakeupq); 497 skb_queue_head_init(l->inputq); 498 return true; 499 } 500 501 /** 502 * tipc_link_bc_create - create new link to be used for broadcast 503 * @n: pointer to associated node 504 * @mtu: mtu to be used initially if no peers 505 * @window: send window to be used 506 * @inputq: queue to put messages ready for delivery 507 * @namedq: queue to put binding table update messages ready for delivery 508 * @link: return value, pointer to put the created link 509 * 510 * Returns true if link was created, otherwise false 511 */ 512 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, 513 int mtu, int window, u16 peer_caps, 514 struct sk_buff_head *inputq, 515 struct sk_buff_head *namedq, 516 struct tipc_link *bc_sndlink, 517 struct tipc_link **link) 518 { 519 struct tipc_link *l; 520 521 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window, 522 0, ownnode, peer, NULL, peer_caps, bc_sndlink, 523 NULL, inputq, namedq, link)) 524 return false; 525 526 l = *link; 527 strcpy(l->name, tipc_bclink_name); 528 tipc_link_reset(l); 529 l->state = LINK_RESET; 530 l->ackers = 0; 531 l->bc_rcvlink = l; 532 533 /* Broadcast send link is always up */ 534 if (link_is_bc_sndlink(l)) 535 l->state = LINK_ESTABLISHED; 536 537 /* Disable replicast if even a single peer doesn't support it */ 538 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST)) 539 tipc_bcast_disable_rcast(net); 540 541 return true; 542 } 543 544 /** 545 * tipc_link_fsm_evt - link finite state machine 546 * @l: pointer to link 547 * @evt: state machine event to be processed 548 */ 549 int tipc_link_fsm_evt(struct tipc_link *l, int evt) 550 { 551 int rc = 0; 552 553 switch (l->state) { 554 case LINK_RESETTING: 555 switch (evt) { 556 case LINK_PEER_RESET_EVT: 557 l->state = LINK_PEER_RESET; 558 break; 559 case LINK_RESET_EVT: 560 l->state = LINK_RESET; 561 break; 562 case LINK_FAILURE_EVT: 563 case LINK_FAILOVER_BEGIN_EVT: 564 case LINK_ESTABLISH_EVT: 565 case LINK_FAILOVER_END_EVT: 566 case LINK_SYNCH_BEGIN_EVT: 567 case LINK_SYNCH_END_EVT: 568 default: 569 goto illegal_evt; 570 } 571 break; 572 case LINK_RESET: 573 switch (evt) { 574 case LINK_PEER_RESET_EVT: 575 l->state = LINK_ESTABLISHING; 576 break; 577 case LINK_FAILOVER_BEGIN_EVT: 578 l->state = LINK_FAILINGOVER; 579 case LINK_FAILURE_EVT: 580 case LINK_RESET_EVT: 581 case LINK_ESTABLISH_EVT: 582 case LINK_FAILOVER_END_EVT: 583 break; 584 case LINK_SYNCH_BEGIN_EVT: 585 case LINK_SYNCH_END_EVT: 586 default: 587 goto illegal_evt; 588 } 589 break; 590 case LINK_PEER_RESET: 591 switch (evt) { 592 case LINK_RESET_EVT: 593 l->state = LINK_ESTABLISHING; 594 break; 595 case LINK_PEER_RESET_EVT: 596 case LINK_ESTABLISH_EVT: 597 case LINK_FAILURE_EVT: 598 break; 599 case LINK_SYNCH_BEGIN_EVT: 600 case LINK_SYNCH_END_EVT: 601 case LINK_FAILOVER_BEGIN_EVT: 602 case LINK_FAILOVER_END_EVT: 603 default: 604 goto illegal_evt; 605 } 606 break; 607 case LINK_FAILINGOVER: 608 switch (evt) { 609 case LINK_FAILOVER_END_EVT: 610 l->state = LINK_RESET; 611 break; 612 case LINK_PEER_RESET_EVT: 613 case LINK_RESET_EVT: 614 case LINK_ESTABLISH_EVT: 615 case LINK_FAILURE_EVT: 616 break; 617 case LINK_FAILOVER_BEGIN_EVT: 618 case LINK_SYNCH_BEGIN_EVT: 619 case LINK_SYNCH_END_EVT: 620 default: 621 goto illegal_evt; 622 } 623 break; 624 case LINK_ESTABLISHING: 625 switch (evt) { 626 case LINK_ESTABLISH_EVT: 627 l->state = LINK_ESTABLISHED; 628 break; 629 case LINK_FAILOVER_BEGIN_EVT: 630 l->state = LINK_FAILINGOVER; 631 break; 632 case LINK_RESET_EVT: 633 l->state = LINK_RESET; 634 break; 635 case LINK_FAILURE_EVT: 636 case LINK_PEER_RESET_EVT: 637 case LINK_SYNCH_BEGIN_EVT: 638 case LINK_FAILOVER_END_EVT: 639 break; 640 case LINK_SYNCH_END_EVT: 641 default: 642 goto illegal_evt; 643 } 644 break; 645 case LINK_ESTABLISHED: 646 switch (evt) { 647 case LINK_PEER_RESET_EVT: 648 l->state = LINK_PEER_RESET; 649 rc |= TIPC_LINK_DOWN_EVT; 650 break; 651 case LINK_FAILURE_EVT: 652 l->state = LINK_RESETTING; 653 rc |= TIPC_LINK_DOWN_EVT; 654 break; 655 case LINK_RESET_EVT: 656 l->state = LINK_RESET; 657 break; 658 case LINK_ESTABLISH_EVT: 659 case LINK_SYNCH_END_EVT: 660 break; 661 case LINK_SYNCH_BEGIN_EVT: 662 l->state = LINK_SYNCHING; 663 break; 664 case LINK_FAILOVER_BEGIN_EVT: 665 case LINK_FAILOVER_END_EVT: 666 default: 667 goto illegal_evt; 668 } 669 break; 670 case LINK_SYNCHING: 671 switch (evt) { 672 case LINK_PEER_RESET_EVT: 673 l->state = LINK_PEER_RESET; 674 rc |= TIPC_LINK_DOWN_EVT; 675 break; 676 case LINK_FAILURE_EVT: 677 l->state = LINK_RESETTING; 678 rc |= TIPC_LINK_DOWN_EVT; 679 break; 680 case LINK_RESET_EVT: 681 l->state = LINK_RESET; 682 break; 683 case LINK_ESTABLISH_EVT: 684 case LINK_SYNCH_BEGIN_EVT: 685 break; 686 case LINK_SYNCH_END_EVT: 687 l->state = LINK_ESTABLISHED; 688 break; 689 case LINK_FAILOVER_BEGIN_EVT: 690 case LINK_FAILOVER_END_EVT: 691 default: 692 goto illegal_evt; 693 } 694 break; 695 default: 696 pr_err("Unknown FSM state %x in %s\n", l->state, l->name); 697 } 698 return rc; 699 illegal_evt: 700 pr_err("Illegal FSM event %x in state %x on link %s\n", 701 evt, l->state, l->name); 702 return rc; 703 } 704 705 /* link_profile_stats - update statistical profiling of traffic 706 */ 707 static void link_profile_stats(struct tipc_link *l) 708 { 709 struct sk_buff *skb; 710 struct tipc_msg *msg; 711 int length; 712 713 /* Update counters used in statistical profiling of send traffic */ 714 l->stats.accu_queue_sz += skb_queue_len(&l->transmq); 715 l->stats.queue_sz_counts++; 716 717 skb = skb_peek(&l->transmq); 718 if (!skb) 719 return; 720 msg = buf_msg(skb); 721 length = msg_size(msg); 722 723 if (msg_user(msg) == MSG_FRAGMENTER) { 724 if (msg_type(msg) != FIRST_FRAGMENT) 725 return; 726 length = msg_size(msg_get_wrapped(msg)); 727 } 728 l->stats.msg_lengths_total += length; 729 l->stats.msg_length_counts++; 730 if (length <= 64) 731 l->stats.msg_length_profile[0]++; 732 else if (length <= 256) 733 l->stats.msg_length_profile[1]++; 734 else if (length <= 1024) 735 l->stats.msg_length_profile[2]++; 736 else if (length <= 4096) 737 l->stats.msg_length_profile[3]++; 738 else if (length <= 16384) 739 l->stats.msg_length_profile[4]++; 740 else if (length <= 32768) 741 l->stats.msg_length_profile[5]++; 742 else 743 l->stats.msg_length_profile[6]++; 744 } 745 746 /* tipc_link_timeout - perform periodic task as instructed from node timeout 747 */ 748 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq) 749 { 750 int mtyp = 0; 751 int rc = 0; 752 bool state = false; 753 bool probe = false; 754 bool setup = false; 755 u16 bc_snt = l->bc_sndlink->snd_nxt - 1; 756 u16 bc_acked = l->bc_rcvlink->acked; 757 struct tipc_mon_state *mstate = &l->mon_state; 758 759 switch (l->state) { 760 case LINK_ESTABLISHED: 761 case LINK_SYNCHING: 762 mtyp = STATE_MSG; 763 link_profile_stats(l); 764 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id); 765 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit)) 766 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 767 state = bc_acked != bc_snt; 768 state |= l->bc_rcvlink->rcv_unacked; 769 state |= l->rcv_unacked; 770 state |= !skb_queue_empty(&l->transmq); 771 state |= !skb_queue_empty(&l->deferdq); 772 probe = mstate->probing; 773 probe |= l->silent_intv_cnt; 774 if (probe || mstate->monitoring) 775 l->silent_intv_cnt++; 776 break; 777 case LINK_RESET: 778 setup = l->rst_cnt++ <= 4; 779 setup |= !(l->rst_cnt % 16); 780 mtyp = RESET_MSG; 781 break; 782 case LINK_ESTABLISHING: 783 setup = true; 784 mtyp = ACTIVATE_MSG; 785 break; 786 case LINK_PEER_RESET: 787 case LINK_RESETTING: 788 case LINK_FAILINGOVER: 789 break; 790 default: 791 break; 792 } 793 794 if (state || probe || setup) 795 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq); 796 797 return rc; 798 } 799 800 /** 801 * link_schedule_user - schedule a message sender for wakeup after congestion 802 * @l: congested link 803 * @hdr: header of message that is being sent 804 * Create pseudo msg to send back to user when congestion abates 805 */ 806 static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr) 807 { 808 u32 dnode = tipc_own_addr(l->net); 809 u32 dport = msg_origport(hdr); 810 struct sk_buff *skb; 811 812 /* Create and schedule wakeup pseudo message */ 813 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0, 814 dnode, l->addr, dport, 0, 0); 815 if (!skb) 816 return -ENOBUFS; 817 msg_set_dest_droppable(buf_msg(skb), true); 818 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr); 819 skb_queue_tail(&l->wakeupq, skb); 820 l->stats.link_congs++; 821 return -ELINKCONG; 822 } 823 824 /** 825 * link_prepare_wakeup - prepare users for wakeup after congestion 826 * @l: congested link 827 * Wake up a number of waiting users, as permitted by available space 828 * in the send queue 829 */ 830 static void link_prepare_wakeup(struct tipc_link *l) 831 { 832 struct sk_buff *skb, *tmp; 833 int imp, i = 0; 834 835 skb_queue_walk_safe(&l->wakeupq, skb, tmp) { 836 imp = TIPC_SKB_CB(skb)->chain_imp; 837 if (l->backlog[imp].len < l->backlog[imp].limit) { 838 skb_unlink(skb, &l->wakeupq); 839 skb_queue_tail(l->inputq, skb); 840 } else if (i++ > 10) { 841 break; 842 } 843 } 844 } 845 846 void tipc_link_reset(struct tipc_link *l) 847 { 848 struct sk_buff_head list; 849 850 __skb_queue_head_init(&list); 851 852 l->in_session = false; 853 l->session++; 854 l->mtu = l->advertised_mtu; 855 856 spin_lock_bh(&l->wakeupq.lock); 857 skb_queue_splice_init(&l->wakeupq, &list); 858 spin_unlock_bh(&l->wakeupq.lock); 859 860 spin_lock_bh(&l->inputq->lock); 861 skb_queue_splice_init(&list, l->inputq); 862 spin_unlock_bh(&l->inputq->lock); 863 864 __skb_queue_purge(&l->transmq); 865 __skb_queue_purge(&l->deferdq); 866 __skb_queue_purge(&l->backlogq); 867 l->backlog[TIPC_LOW_IMPORTANCE].len = 0; 868 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0; 869 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0; 870 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0; 871 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0; 872 kfree_skb(l->reasm_buf); 873 kfree_skb(l->failover_reasm_skb); 874 l->reasm_buf = NULL; 875 l->failover_reasm_skb = NULL; 876 l->rcv_unacked = 0; 877 l->snd_nxt = 1; 878 l->rcv_nxt = 1; 879 l->snd_nxt_state = 1; 880 l->rcv_nxt_state = 1; 881 l->acked = 0; 882 l->silent_intv_cnt = 0; 883 l->rst_cnt = 0; 884 l->stale_cnt = 0; 885 l->bc_peer_is_up = false; 886 memset(&l->mon_state, 0, sizeof(l->mon_state)); 887 tipc_link_reset_stats(l); 888 } 889 890 /** 891 * tipc_link_xmit(): enqueue buffer list according to queue situation 892 * @link: link to use 893 * @list: chain of buffers containing message 894 * @xmitq: returned list of packets to be sent by caller 895 * 896 * Consumes the buffer chain. 897 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS 898 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted 899 */ 900 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list, 901 struct sk_buff_head *xmitq) 902 { 903 struct tipc_msg *hdr = buf_msg(skb_peek(list)); 904 unsigned int maxwin = l->window; 905 int imp = msg_importance(hdr); 906 unsigned int mtu = l->mtu; 907 u16 ack = l->rcv_nxt - 1; 908 u16 seqno = l->snd_nxt; 909 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 910 struct sk_buff_head *transmq = &l->transmq; 911 struct sk_buff_head *backlogq = &l->backlogq; 912 struct sk_buff *skb, *_skb, *bskb; 913 int pkt_cnt = skb_queue_len(list); 914 int rc = 0; 915 916 if (unlikely(msg_size(hdr) > mtu)) { 917 skb_queue_purge(list); 918 return -EMSGSIZE; 919 } 920 921 /* Allow oversubscription of one data msg per source at congestion */ 922 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) { 923 if (imp == TIPC_SYSTEM_IMPORTANCE) { 924 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name); 925 return -ENOBUFS; 926 } 927 rc = link_schedule_user(l, hdr); 928 } 929 930 if (pkt_cnt > 1) { 931 l->stats.sent_fragmented++; 932 l->stats.sent_fragments += pkt_cnt; 933 } 934 935 /* Prepare each packet for sending, and add to relevant queue: */ 936 while (skb_queue_len(list)) { 937 skb = skb_peek(list); 938 hdr = buf_msg(skb); 939 msg_set_seqno(hdr, seqno); 940 msg_set_ack(hdr, ack); 941 msg_set_bcast_ack(hdr, bc_ack); 942 943 if (likely(skb_queue_len(transmq) < maxwin)) { 944 _skb = skb_clone(skb, GFP_ATOMIC); 945 if (!_skb) { 946 skb_queue_purge(list); 947 return -ENOBUFS; 948 } 949 __skb_dequeue(list); 950 __skb_queue_tail(transmq, skb); 951 __skb_queue_tail(xmitq, _skb); 952 TIPC_SKB_CB(skb)->ackers = l->ackers; 953 l->rcv_unacked = 0; 954 l->stats.sent_pkts++; 955 seqno++; 956 continue; 957 } 958 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) { 959 kfree_skb(__skb_dequeue(list)); 960 l->stats.sent_bundled++; 961 continue; 962 } 963 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) { 964 kfree_skb(__skb_dequeue(list)); 965 __skb_queue_tail(backlogq, bskb); 966 l->backlog[msg_importance(buf_msg(bskb))].len++; 967 l->stats.sent_bundled++; 968 l->stats.sent_bundles++; 969 continue; 970 } 971 l->backlog[imp].len += skb_queue_len(list); 972 skb_queue_splice_tail_init(list, backlogq); 973 } 974 l->snd_nxt = seqno; 975 return rc; 976 } 977 978 static void tipc_link_advance_backlog(struct tipc_link *l, 979 struct sk_buff_head *xmitq) 980 { 981 struct sk_buff *skb, *_skb; 982 struct tipc_msg *hdr; 983 u16 seqno = l->snd_nxt; 984 u16 ack = l->rcv_nxt - 1; 985 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 986 987 while (skb_queue_len(&l->transmq) < l->window) { 988 skb = skb_peek(&l->backlogq); 989 if (!skb) 990 break; 991 _skb = skb_clone(skb, GFP_ATOMIC); 992 if (!_skb) 993 break; 994 __skb_dequeue(&l->backlogq); 995 hdr = buf_msg(skb); 996 l->backlog[msg_importance(hdr)].len--; 997 __skb_queue_tail(&l->transmq, skb); 998 __skb_queue_tail(xmitq, _skb); 999 TIPC_SKB_CB(skb)->ackers = l->ackers; 1000 msg_set_seqno(hdr, seqno); 1001 msg_set_ack(hdr, ack); 1002 msg_set_bcast_ack(hdr, bc_ack); 1003 l->rcv_unacked = 0; 1004 l->stats.sent_pkts++; 1005 seqno++; 1006 } 1007 l->snd_nxt = seqno; 1008 } 1009 1010 static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb) 1011 { 1012 struct tipc_msg *hdr = buf_msg(skb); 1013 1014 pr_warn("Retransmission failure on link <%s>\n", l->name); 1015 link_print(l, "State of link "); 1016 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n", 1017 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr)); 1018 pr_info("sqno %u, prev: %x, src: %x\n", 1019 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr)); 1020 } 1021 1022 /* tipc_link_retrans() - retransmit one or more packets 1023 * @l: the link to transmit on 1024 * @r: the receiving link ordering the retransmit. Same as l if unicast 1025 * @from: retransmit from (inclusive) this sequence number 1026 * @to: retransmit to (inclusive) this sequence number 1027 * xmitq: queue for accumulating the retransmitted packets 1028 */ 1029 static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r, 1030 u16 from, u16 to, struct sk_buff_head *xmitq) 1031 { 1032 struct sk_buff *_skb, *skb = skb_peek(&l->transmq); 1033 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 1034 u16 ack = l->rcv_nxt - 1; 1035 struct tipc_msg *hdr; 1036 1037 if (!skb) 1038 return 0; 1039 1040 /* Detect repeated retransmit failures on same packet */ 1041 if (r->last_retransm != buf_seqno(skb)) { 1042 r->last_retransm = buf_seqno(skb); 1043 r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance); 1044 r->stale_cnt = 0; 1045 } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) { 1046 link_retransmit_failure(l, skb); 1047 if (link_is_bc_sndlink(l)) 1048 return TIPC_LINK_DOWN_EVT; 1049 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1050 } 1051 1052 skb_queue_walk(&l->transmq, skb) { 1053 hdr = buf_msg(skb); 1054 if (less(msg_seqno(hdr), from)) 1055 continue; 1056 if (more(msg_seqno(hdr), to)) 1057 break; 1058 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC); 1059 if (!_skb) 1060 return 0; 1061 hdr = buf_msg(_skb); 1062 msg_set_ack(hdr, ack); 1063 msg_set_bcast_ack(hdr, bc_ack); 1064 _skb->priority = TC_PRIO_CONTROL; 1065 __skb_queue_tail(xmitq, _skb); 1066 l->stats.retransmitted++; 1067 } 1068 return 0; 1069 } 1070 1071 /* tipc_data_input - deliver data and name distr msgs to upper layer 1072 * 1073 * Consumes buffer if message is of right type 1074 * Node lock must be held 1075 */ 1076 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb, 1077 struct sk_buff_head *inputq) 1078 { 1079 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq; 1080 struct tipc_msg *hdr = buf_msg(skb); 1081 1082 switch (msg_user(hdr)) { 1083 case TIPC_LOW_IMPORTANCE: 1084 case TIPC_MEDIUM_IMPORTANCE: 1085 case TIPC_HIGH_IMPORTANCE: 1086 case TIPC_CRITICAL_IMPORTANCE: 1087 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) { 1088 skb_queue_tail(mc_inputq, skb); 1089 return true; 1090 } 1091 /* else: fall through */ 1092 case CONN_MANAGER: 1093 skb_queue_tail(inputq, skb); 1094 return true; 1095 case GROUP_PROTOCOL: 1096 skb_queue_tail(mc_inputq, skb); 1097 return true; 1098 case NAME_DISTRIBUTOR: 1099 l->bc_rcvlink->state = LINK_ESTABLISHED; 1100 skb_queue_tail(l->namedq, skb); 1101 return true; 1102 case MSG_BUNDLER: 1103 case TUNNEL_PROTOCOL: 1104 case MSG_FRAGMENTER: 1105 case BCAST_PROTOCOL: 1106 return false; 1107 default: 1108 pr_warn("Dropping received illegal msg type\n"); 1109 kfree_skb(skb); 1110 return false; 1111 }; 1112 } 1113 1114 /* tipc_link_input - process packet that has passed link protocol check 1115 * 1116 * Consumes buffer 1117 */ 1118 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb, 1119 struct sk_buff_head *inputq) 1120 { 1121 struct tipc_msg *hdr = buf_msg(skb); 1122 struct sk_buff **reasm_skb = &l->reasm_buf; 1123 struct sk_buff *iskb; 1124 struct sk_buff_head tmpq; 1125 int usr = msg_user(hdr); 1126 int rc = 0; 1127 int pos = 0; 1128 int ipos = 0; 1129 1130 if (unlikely(usr == TUNNEL_PROTOCOL)) { 1131 if (msg_type(hdr) == SYNCH_MSG) { 1132 __skb_queue_purge(&l->deferdq); 1133 goto drop; 1134 } 1135 if (!tipc_msg_extract(skb, &iskb, &ipos)) 1136 return rc; 1137 kfree_skb(skb); 1138 skb = iskb; 1139 hdr = buf_msg(skb); 1140 if (less(msg_seqno(hdr), l->drop_point)) 1141 goto drop; 1142 if (tipc_data_input(l, skb, inputq)) 1143 return rc; 1144 usr = msg_user(hdr); 1145 reasm_skb = &l->failover_reasm_skb; 1146 } 1147 1148 if (usr == MSG_BUNDLER) { 1149 skb_queue_head_init(&tmpq); 1150 l->stats.recv_bundles++; 1151 l->stats.recv_bundled += msg_msgcnt(hdr); 1152 while (tipc_msg_extract(skb, &iskb, &pos)) 1153 tipc_data_input(l, iskb, &tmpq); 1154 tipc_skb_queue_splice_tail(&tmpq, inputq); 1155 return 0; 1156 } else if (usr == MSG_FRAGMENTER) { 1157 l->stats.recv_fragments++; 1158 if (tipc_buf_append(reasm_skb, &skb)) { 1159 l->stats.recv_fragmented++; 1160 tipc_data_input(l, skb, inputq); 1161 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) { 1162 pr_warn_ratelimited("Unable to build fragment list\n"); 1163 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1164 } 1165 return 0; 1166 } else if (usr == BCAST_PROTOCOL) { 1167 tipc_bcast_lock(l->net); 1168 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr); 1169 tipc_bcast_unlock(l->net); 1170 } 1171 drop: 1172 kfree_skb(skb); 1173 return 0; 1174 } 1175 1176 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked) 1177 { 1178 bool released = false; 1179 struct sk_buff *skb, *tmp; 1180 1181 skb_queue_walk_safe(&l->transmq, skb, tmp) { 1182 if (more(buf_seqno(skb), acked)) 1183 break; 1184 __skb_unlink(skb, &l->transmq); 1185 kfree_skb(skb); 1186 released = true; 1187 } 1188 return released; 1189 } 1190 1191 /* tipc_link_build_state_msg: prepare link state message for transmission 1192 * 1193 * Note that sending of broadcast ack is coordinated among nodes, to reduce 1194 * risk of ack storms towards the sender 1195 */ 1196 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 1197 { 1198 if (!l) 1199 return 0; 1200 1201 /* Broadcast ACK must be sent via a unicast link => defer to caller */ 1202 if (link_is_bc_rcvlink(l)) { 1203 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf) 1204 return 0; 1205 l->rcv_unacked = 0; 1206 1207 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */ 1208 l->snd_nxt = l->rcv_nxt; 1209 return TIPC_LINK_SND_STATE; 1210 } 1211 1212 /* Unicast ACK */ 1213 l->rcv_unacked = 0; 1214 l->stats.sent_acks++; 1215 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq); 1216 return 0; 1217 } 1218 1219 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message 1220 */ 1221 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 1222 { 1223 int mtyp = RESET_MSG; 1224 struct sk_buff *skb; 1225 1226 if (l->state == LINK_ESTABLISHING) 1227 mtyp = ACTIVATE_MSG; 1228 1229 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq); 1230 1231 /* Inform peer that this endpoint is going down if applicable */ 1232 skb = skb_peek_tail(xmitq); 1233 if (skb && (l->state == LINK_RESET)) 1234 msg_set_peer_stopping(buf_msg(skb), 1); 1235 } 1236 1237 /* tipc_link_build_nack_msg: prepare link nack message for transmission 1238 * Note that sending of broadcast NACK is coordinated among nodes, to 1239 * reduce the risk of NACK storms towards the sender 1240 */ 1241 static int tipc_link_build_nack_msg(struct tipc_link *l, 1242 struct sk_buff_head *xmitq) 1243 { 1244 u32 def_cnt = ++l->stats.deferred_recv; 1245 int match1, match2; 1246 1247 if (link_is_bc_rcvlink(l)) { 1248 match1 = def_cnt & 0xf; 1249 match2 = tipc_own_addr(l->net) & 0xf; 1250 if (match1 == match2) 1251 return TIPC_LINK_SND_STATE; 1252 return 0; 1253 } 1254 1255 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV)) 1256 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq); 1257 return 0; 1258 } 1259 1260 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node 1261 * @l: the link that should handle the message 1262 * @skb: TIPC packet 1263 * @xmitq: queue to place packets to be sent after this call 1264 */ 1265 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, 1266 struct sk_buff_head *xmitq) 1267 { 1268 struct sk_buff_head *defq = &l->deferdq; 1269 struct tipc_msg *hdr; 1270 u16 seqno, rcv_nxt, win_lim; 1271 int rc = 0; 1272 1273 do { 1274 hdr = buf_msg(skb); 1275 seqno = msg_seqno(hdr); 1276 rcv_nxt = l->rcv_nxt; 1277 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN; 1278 1279 /* Verify and update link state */ 1280 if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) 1281 return tipc_link_proto_rcv(l, skb, xmitq); 1282 1283 if (unlikely(!link_is_up(l))) { 1284 if (l->state == LINK_ESTABLISHING) 1285 rc = TIPC_LINK_UP_EVT; 1286 goto drop; 1287 } 1288 1289 /* Don't send probe at next timeout expiration */ 1290 l->silent_intv_cnt = 0; 1291 1292 /* Drop if outside receive window */ 1293 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) { 1294 l->stats.duplicates++; 1295 goto drop; 1296 } 1297 1298 /* Forward queues and wake up waiting users */ 1299 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) { 1300 l->stale_cnt = 0; 1301 tipc_link_advance_backlog(l, xmitq); 1302 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1303 link_prepare_wakeup(l); 1304 } 1305 1306 /* Defer delivery if sequence gap */ 1307 if (unlikely(seqno != rcv_nxt)) { 1308 __tipc_skb_queue_sorted(defq, seqno, skb); 1309 rc |= tipc_link_build_nack_msg(l, xmitq); 1310 break; 1311 } 1312 1313 /* Deliver packet */ 1314 l->rcv_nxt++; 1315 l->stats.recv_pkts++; 1316 if (!tipc_data_input(l, skb, l->inputq)) 1317 rc |= tipc_link_input(l, skb, l->inputq); 1318 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN)) 1319 rc |= tipc_link_build_state_msg(l, xmitq); 1320 if (unlikely(rc & ~TIPC_LINK_SND_STATE)) 1321 break; 1322 } while ((skb = __skb_dequeue(defq))); 1323 1324 return rc; 1325 drop: 1326 kfree_skb(skb); 1327 return rc; 1328 } 1329 1330 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, 1331 bool probe_reply, u16 rcvgap, 1332 int tolerance, int priority, 1333 struct sk_buff_head *xmitq) 1334 { 1335 struct tipc_link *bcl = l->bc_rcvlink; 1336 struct sk_buff *skb; 1337 struct tipc_msg *hdr; 1338 struct sk_buff_head *dfq = &l->deferdq; 1339 bool node_up = link_is_up(bcl); 1340 struct tipc_mon_state *mstate = &l->mon_state; 1341 int dlen = 0; 1342 void *data; 1343 1344 /* Don't send protocol message during reset or link failover */ 1345 if (tipc_link_is_blocked(l)) 1346 return; 1347 1348 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG)) 1349 return; 1350 1351 if (!skb_queue_empty(dfq)) 1352 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt; 1353 1354 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE, 1355 tipc_max_domain_size, l->addr, 1356 tipc_own_addr(l->net), 0, 0, 0); 1357 if (!skb) 1358 return; 1359 1360 hdr = buf_msg(skb); 1361 data = msg_data(hdr); 1362 msg_set_session(hdr, l->session); 1363 msg_set_bearer_id(hdr, l->bearer_id); 1364 msg_set_net_plane(hdr, l->net_plane); 1365 msg_set_next_sent(hdr, l->snd_nxt); 1366 msg_set_ack(hdr, l->rcv_nxt - 1); 1367 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1); 1368 msg_set_bc_ack_invalid(hdr, !node_up); 1369 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1370 msg_set_link_tolerance(hdr, tolerance); 1371 msg_set_linkprio(hdr, priority); 1372 msg_set_redundant_link(hdr, node_up); 1373 msg_set_seq_gap(hdr, 0); 1374 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2); 1375 1376 if (mtyp == STATE_MSG) { 1377 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO) 1378 msg_set_seqno(hdr, l->snd_nxt_state++); 1379 msg_set_seq_gap(hdr, rcvgap); 1380 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl)); 1381 msg_set_probe(hdr, probe); 1382 msg_set_is_keepalive(hdr, probe || probe_reply); 1383 tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id); 1384 msg_set_size(hdr, INT_H_SIZE + dlen); 1385 skb_trim(skb, INT_H_SIZE + dlen); 1386 l->stats.sent_states++; 1387 l->rcv_unacked = 0; 1388 } else { 1389 /* RESET_MSG or ACTIVATE_MSG */ 1390 msg_set_max_pkt(hdr, l->advertised_mtu); 1391 strcpy(data, l->if_name); 1392 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME); 1393 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME); 1394 } 1395 if (probe) 1396 l->stats.sent_probes++; 1397 if (rcvgap) 1398 l->stats.sent_nacks++; 1399 skb->priority = TC_PRIO_CONTROL; 1400 __skb_queue_tail(xmitq, skb); 1401 } 1402 1403 void tipc_link_create_dummy_tnl_msg(struct tipc_link *l, 1404 struct sk_buff_head *xmitq) 1405 { 1406 u32 onode = tipc_own_addr(l->net); 1407 struct tipc_msg *hdr, *ihdr; 1408 struct sk_buff_head tnlq; 1409 struct sk_buff *skb; 1410 u32 dnode = l->addr; 1411 1412 skb_queue_head_init(&tnlq); 1413 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG, 1414 INT_H_SIZE, BASIC_H_SIZE, 1415 dnode, onode, 0, 0, 0); 1416 if (!skb) { 1417 pr_warn("%sunable to create tunnel packet\n", link_co_err); 1418 return; 1419 } 1420 1421 hdr = buf_msg(skb); 1422 msg_set_msgcnt(hdr, 1); 1423 msg_set_bearer_id(hdr, l->peer_bearer_id); 1424 1425 ihdr = (struct tipc_msg *)msg_data(hdr); 1426 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG, 1427 BASIC_H_SIZE, dnode); 1428 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT); 1429 __skb_queue_tail(&tnlq, skb); 1430 tipc_link_xmit(l, &tnlq, xmitq); 1431 } 1432 1433 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets 1434 * with contents of the link's transmit and backlog queues. 1435 */ 1436 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, 1437 int mtyp, struct sk_buff_head *xmitq) 1438 { 1439 struct sk_buff *skb, *tnlskb; 1440 struct tipc_msg *hdr, tnlhdr; 1441 struct sk_buff_head *queue = &l->transmq; 1442 struct sk_buff_head tmpxq, tnlq; 1443 u16 pktlen, pktcnt, seqno = l->snd_nxt; 1444 1445 if (!tnl) 1446 return; 1447 1448 skb_queue_head_init(&tnlq); 1449 skb_queue_head_init(&tmpxq); 1450 1451 /* At least one packet required for safe algorithm => add dummy */ 1452 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG, 1453 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net), 1454 0, 0, TIPC_ERR_NO_PORT); 1455 if (!skb) { 1456 pr_warn("%sunable to create tunnel packet\n", link_co_err); 1457 return; 1458 } 1459 skb_queue_tail(&tnlq, skb); 1460 tipc_link_xmit(l, &tnlq, &tmpxq); 1461 __skb_queue_purge(&tmpxq); 1462 1463 /* Initialize reusable tunnel packet header */ 1464 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL, 1465 mtyp, INT_H_SIZE, l->addr); 1466 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq); 1467 msg_set_msgcnt(&tnlhdr, pktcnt); 1468 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id); 1469 tnl: 1470 /* Wrap each packet into a tunnel packet */ 1471 skb_queue_walk(queue, skb) { 1472 hdr = buf_msg(skb); 1473 if (queue == &l->backlogq) 1474 msg_set_seqno(hdr, seqno++); 1475 pktlen = msg_size(hdr); 1476 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE); 1477 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC); 1478 if (!tnlskb) { 1479 pr_warn("%sunable to send packet\n", link_co_err); 1480 return; 1481 } 1482 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE); 1483 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen); 1484 __skb_queue_tail(&tnlq, tnlskb); 1485 } 1486 if (queue != &l->backlogq) { 1487 queue = &l->backlogq; 1488 goto tnl; 1489 } 1490 1491 tipc_link_xmit(tnl, &tnlq, xmitq); 1492 1493 if (mtyp == FAILOVER_MSG) { 1494 tnl->drop_point = l->rcv_nxt; 1495 tnl->failover_reasm_skb = l->reasm_buf; 1496 l->reasm_buf = NULL; 1497 } 1498 } 1499 1500 /* tipc_link_validate_msg(): validate message against current link state 1501 * Returns true if message should be accepted, otherwise false 1502 */ 1503 bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr) 1504 { 1505 u16 curr_session = l->peer_session; 1506 u16 session = msg_session(hdr); 1507 int mtyp = msg_type(hdr); 1508 1509 if (msg_user(hdr) != LINK_PROTOCOL) 1510 return true; 1511 1512 switch (mtyp) { 1513 case RESET_MSG: 1514 if (!l->in_session) 1515 return true; 1516 /* Accept only RESET with new session number */ 1517 return more(session, curr_session); 1518 case ACTIVATE_MSG: 1519 if (!l->in_session) 1520 return true; 1521 /* Accept only ACTIVATE with new or current session number */ 1522 return !less(session, curr_session); 1523 case STATE_MSG: 1524 /* Accept only STATE with current session number */ 1525 if (!l->in_session) 1526 return false; 1527 if (session != curr_session) 1528 return false; 1529 /* Extra sanity check */ 1530 if (!link_is_up(l) && msg_ack(hdr)) 1531 return false; 1532 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO)) 1533 return true; 1534 /* Accept only STATE with new sequence number */ 1535 return !less(msg_seqno(hdr), l->rcv_nxt_state); 1536 default: 1537 return false; 1538 } 1539 } 1540 1541 /* tipc_link_proto_rcv(): receive link level protocol message : 1542 * Note that network plane id propagates through the network, and may 1543 * change at any time. The node with lowest numerical id determines 1544 * network plane 1545 */ 1546 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, 1547 struct sk_buff_head *xmitq) 1548 { 1549 struct tipc_msg *hdr = buf_msg(skb); 1550 u16 rcvgap = 0; 1551 u16 ack = msg_ack(hdr); 1552 u16 gap = msg_seq_gap(hdr); 1553 u16 peers_snd_nxt = msg_next_sent(hdr); 1554 u16 peers_tol = msg_link_tolerance(hdr); 1555 u16 peers_prio = msg_linkprio(hdr); 1556 u16 rcv_nxt = l->rcv_nxt; 1557 u16 dlen = msg_data_sz(hdr); 1558 int mtyp = msg_type(hdr); 1559 bool reply = msg_probe(hdr); 1560 void *data; 1561 char *if_name; 1562 int rc = 0; 1563 1564 if (tipc_link_is_blocked(l) || !xmitq) 1565 goto exit; 1566 1567 if (tipc_own_addr(l->net) > msg_prevnode(hdr)) 1568 l->net_plane = msg_net_plane(hdr); 1569 1570 skb_linearize(skb); 1571 hdr = buf_msg(skb); 1572 data = msg_data(hdr); 1573 1574 if (!tipc_link_validate_msg(l, hdr)) 1575 goto exit; 1576 1577 switch (mtyp) { 1578 case RESET_MSG: 1579 case ACTIVATE_MSG: 1580 /* Complete own link name with peer's interface name */ 1581 if_name = strrchr(l->name, ':') + 1; 1582 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME) 1583 break; 1584 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME) 1585 break; 1586 strncpy(if_name, data, TIPC_MAX_IF_NAME); 1587 1588 /* Update own tolerance if peer indicates a non-zero value */ 1589 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) { 1590 l->tolerance = peers_tol; 1591 l->bc_rcvlink->tolerance = peers_tol; 1592 } 1593 /* Update own priority if peer's priority is higher */ 1594 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI)) 1595 l->priority = peers_prio; 1596 1597 /* If peer is going down we want full re-establish cycle */ 1598 if (msg_peer_stopping(hdr)) { 1599 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1600 break; 1601 } 1602 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */ 1603 if (mtyp == RESET_MSG || !link_is_up(l)) 1604 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); 1605 1606 /* ACTIVATE_MSG takes up link if it was already locally reset */ 1607 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING) 1608 rc = TIPC_LINK_UP_EVT; 1609 1610 l->peer_session = msg_session(hdr); 1611 l->in_session = true; 1612 l->peer_bearer_id = msg_bearer_id(hdr); 1613 if (l->mtu > msg_max_pkt(hdr)) 1614 l->mtu = msg_max_pkt(hdr); 1615 break; 1616 1617 case STATE_MSG: 1618 l->rcv_nxt_state = msg_seqno(hdr) + 1; 1619 1620 /* Update own tolerance if peer indicates a non-zero value */ 1621 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) { 1622 l->tolerance = peers_tol; 1623 l->bc_rcvlink->tolerance = peers_tol; 1624 } 1625 /* Update own prio if peer indicates a different value */ 1626 if ((peers_prio != l->priority) && 1627 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) { 1628 l->priority = peers_prio; 1629 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1630 } 1631 1632 l->silent_intv_cnt = 0; 1633 l->stats.recv_states++; 1634 if (msg_probe(hdr)) 1635 l->stats.recv_probes++; 1636 1637 if (!link_is_up(l)) { 1638 if (l->state == LINK_ESTABLISHING) 1639 rc = TIPC_LINK_UP_EVT; 1640 break; 1641 } 1642 tipc_mon_rcv(l->net, data, dlen, l->addr, 1643 &l->mon_state, l->bearer_id); 1644 1645 /* Send NACK if peer has sent pkts we haven't received yet */ 1646 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l)) 1647 rcvgap = peers_snd_nxt - l->rcv_nxt; 1648 if (rcvgap || reply) 1649 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply, 1650 rcvgap, 0, 0, xmitq); 1651 tipc_link_release_pkts(l, ack); 1652 1653 /* If NACK, retransmit will now start at right position */ 1654 if (gap) { 1655 rc = tipc_link_retrans(l, l, ack + 1, ack + gap, xmitq); 1656 l->stats.recv_nacks++; 1657 } 1658 1659 tipc_link_advance_backlog(l, xmitq); 1660 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1661 link_prepare_wakeup(l); 1662 } 1663 exit: 1664 kfree_skb(skb); 1665 return rc; 1666 } 1667 1668 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message 1669 */ 1670 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast, 1671 u16 peers_snd_nxt, 1672 struct sk_buff_head *xmitq) 1673 { 1674 struct sk_buff *skb; 1675 struct tipc_msg *hdr; 1676 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq); 1677 u16 ack = l->rcv_nxt - 1; 1678 u16 gap_to = peers_snd_nxt - 1; 1679 1680 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, 1681 0, l->addr, tipc_own_addr(l->net), 0, 0, 0); 1682 if (!skb) 1683 return false; 1684 hdr = buf_msg(skb); 1685 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1686 msg_set_bcast_ack(hdr, ack); 1687 msg_set_bcgap_after(hdr, ack); 1688 if (dfrd_skb) 1689 gap_to = buf_seqno(dfrd_skb) - 1; 1690 msg_set_bcgap_to(hdr, gap_to); 1691 msg_set_non_seq(hdr, bcast); 1692 __skb_queue_tail(xmitq, skb); 1693 return true; 1694 } 1695 1696 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints. 1697 * 1698 * Give a newly added peer node the sequence number where it should 1699 * start receiving and acking broadcast packets. 1700 */ 1701 static void tipc_link_build_bc_init_msg(struct tipc_link *l, 1702 struct sk_buff_head *xmitq) 1703 { 1704 struct sk_buff_head list; 1705 1706 __skb_queue_head_init(&list); 1707 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list)) 1708 return; 1709 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true); 1710 tipc_link_xmit(l, &list, xmitq); 1711 } 1712 1713 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer 1714 */ 1715 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr) 1716 { 1717 int mtyp = msg_type(hdr); 1718 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 1719 1720 if (link_is_up(l)) 1721 return; 1722 1723 if (msg_user(hdr) == BCAST_PROTOCOL) { 1724 l->rcv_nxt = peers_snd_nxt; 1725 l->state = LINK_ESTABLISHED; 1726 return; 1727 } 1728 1729 if (l->peer_caps & TIPC_BCAST_SYNCH) 1730 return; 1731 1732 if (msg_peer_node_is_up(hdr)) 1733 return; 1734 1735 /* Compatibility: accept older, less safe initial synch data */ 1736 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG)) 1737 l->rcv_nxt = peers_snd_nxt; 1738 } 1739 1740 /* link_bc_retr eval()- check if the indicated range can be retransmitted now 1741 * - Adjust permitted range if there is overlap with previous retransmission 1742 */ 1743 static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to) 1744 { 1745 unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr); 1746 1747 if (less(*to, *from)) 1748 return false; 1749 1750 /* New retransmission request */ 1751 if ((elapsed > TIPC_BC_RETR_LIMIT) || 1752 less(*to, l->prev_from) || more(*from, l->prev_to)) { 1753 l->prev_from = *from; 1754 l->prev_to = *to; 1755 l->prev_retr = jiffies; 1756 return true; 1757 } 1758 1759 /* Inside range of previous retransmit */ 1760 if (!less(*from, l->prev_from) && !more(*to, l->prev_to)) 1761 return false; 1762 1763 /* Fully or partially outside previous range => exclude overlap */ 1764 if (less(*from, l->prev_from)) { 1765 *to = l->prev_from - 1; 1766 l->prev_from = *from; 1767 } 1768 if (more(*to, l->prev_to)) { 1769 *from = l->prev_to + 1; 1770 l->prev_to = *to; 1771 } 1772 l->prev_retr = jiffies; 1773 return true; 1774 } 1775 1776 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state 1777 */ 1778 int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr, 1779 struct sk_buff_head *xmitq) 1780 { 1781 struct tipc_link *snd_l = l->bc_sndlink; 1782 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 1783 u16 from = msg_bcast_ack(hdr) + 1; 1784 u16 to = from + msg_bc_gap(hdr) - 1; 1785 int rc = 0; 1786 1787 if (!link_is_up(l)) 1788 return rc; 1789 1790 if (!msg_peer_node_is_up(hdr)) 1791 return rc; 1792 1793 /* Open when peer ackowledges our bcast init msg (pkt #1) */ 1794 if (msg_ack(hdr)) 1795 l->bc_peer_is_up = true; 1796 1797 if (!l->bc_peer_is_up) 1798 return rc; 1799 1800 l->stats.recv_nacks++; 1801 1802 /* Ignore if peers_snd_nxt goes beyond receive window */ 1803 if (more(peers_snd_nxt, l->rcv_nxt + l->window)) 1804 return rc; 1805 1806 if (link_bc_retr_eval(snd_l, &from, &to)) 1807 rc = tipc_link_retrans(snd_l, l, from, to, xmitq); 1808 1809 l->snd_nxt = peers_snd_nxt; 1810 if (link_bc_rcv_gap(l)) 1811 rc |= TIPC_LINK_SND_STATE; 1812 1813 /* Return now if sender supports nack via STATE messages */ 1814 if (l->peer_caps & TIPC_BCAST_STATE_NACK) 1815 return rc; 1816 1817 /* Otherwise, be backwards compatible */ 1818 1819 if (!more(peers_snd_nxt, l->rcv_nxt)) { 1820 l->nack_state = BC_NACK_SND_CONDITIONAL; 1821 return 0; 1822 } 1823 1824 /* Don't NACK if one was recently sent or peeked */ 1825 if (l->nack_state == BC_NACK_SND_SUPPRESS) { 1826 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 1827 return 0; 1828 } 1829 1830 /* Conditionally delay NACK sending until next synch rcv */ 1831 if (l->nack_state == BC_NACK_SND_CONDITIONAL) { 1832 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 1833 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN) 1834 return 0; 1835 } 1836 1837 /* Send NACK now but suppress next one */ 1838 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq); 1839 l->nack_state = BC_NACK_SND_SUPPRESS; 1840 return 0; 1841 } 1842 1843 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked, 1844 struct sk_buff_head *xmitq) 1845 { 1846 struct sk_buff *skb, *tmp; 1847 struct tipc_link *snd_l = l->bc_sndlink; 1848 1849 if (!link_is_up(l) || !l->bc_peer_is_up) 1850 return; 1851 1852 if (!more(acked, l->acked)) 1853 return; 1854 1855 /* Skip over packets peer has already acked */ 1856 skb_queue_walk(&snd_l->transmq, skb) { 1857 if (more(buf_seqno(skb), l->acked)) 1858 break; 1859 } 1860 1861 /* Update/release the packets peer is acking now */ 1862 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) { 1863 if (more(buf_seqno(skb), acked)) 1864 break; 1865 if (!--TIPC_SKB_CB(skb)->ackers) { 1866 __skb_unlink(skb, &snd_l->transmq); 1867 kfree_skb(skb); 1868 } 1869 } 1870 l->acked = acked; 1871 tipc_link_advance_backlog(snd_l, xmitq); 1872 if (unlikely(!skb_queue_empty(&snd_l->wakeupq))) 1873 link_prepare_wakeup(snd_l); 1874 } 1875 1876 /* tipc_link_bc_nack_rcv(): receive broadcast nack message 1877 * This function is here for backwards compatibility, since 1878 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5. 1879 */ 1880 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb, 1881 struct sk_buff_head *xmitq) 1882 { 1883 struct tipc_msg *hdr = buf_msg(skb); 1884 u32 dnode = msg_destnode(hdr); 1885 int mtyp = msg_type(hdr); 1886 u16 acked = msg_bcast_ack(hdr); 1887 u16 from = acked + 1; 1888 u16 to = msg_bcgap_to(hdr); 1889 u16 peers_snd_nxt = to + 1; 1890 int rc = 0; 1891 1892 kfree_skb(skb); 1893 1894 if (!tipc_link_is_up(l) || !l->bc_peer_is_up) 1895 return 0; 1896 1897 if (mtyp != STATE_MSG) 1898 return 0; 1899 1900 if (dnode == tipc_own_addr(l->net)) { 1901 tipc_link_bc_ack_rcv(l, acked, xmitq); 1902 rc = tipc_link_retrans(l->bc_sndlink, l, from, to, xmitq); 1903 l->stats.recv_nacks++; 1904 return rc; 1905 } 1906 1907 /* Msg for other node => suppress own NACK at next sync if applicable */ 1908 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from)) 1909 l->nack_state = BC_NACK_SND_SUPPRESS; 1910 1911 return 0; 1912 } 1913 1914 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win) 1915 { 1916 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE); 1917 1918 l->window = win; 1919 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win); 1920 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2); 1921 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3); 1922 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4); 1923 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk; 1924 } 1925 1926 /** 1927 * link_reset_stats - reset link statistics 1928 * @l: pointer to link 1929 */ 1930 void tipc_link_reset_stats(struct tipc_link *l) 1931 { 1932 memset(&l->stats, 0, sizeof(l->stats)); 1933 } 1934 1935 static void link_print(struct tipc_link *l, const char *str) 1936 { 1937 struct sk_buff *hskb = skb_peek(&l->transmq); 1938 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1; 1939 u16 tail = l->snd_nxt - 1; 1940 1941 pr_info("%s Link <%s> state %x\n", str, l->name, l->state); 1942 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n", 1943 skb_queue_len(&l->transmq), head, tail, 1944 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt); 1945 } 1946 1947 /* Parse and validate nested (link) properties valid for media, bearer and link 1948 */ 1949 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]) 1950 { 1951 int err; 1952 1953 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop, 1954 tipc_nl_prop_policy, NULL); 1955 if (err) 1956 return err; 1957 1958 if (props[TIPC_NLA_PROP_PRIO]) { 1959 u32 prio; 1960 1961 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); 1962 if (prio > TIPC_MAX_LINK_PRI) 1963 return -EINVAL; 1964 } 1965 1966 if (props[TIPC_NLA_PROP_TOL]) { 1967 u32 tol; 1968 1969 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); 1970 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL)) 1971 return -EINVAL; 1972 } 1973 1974 if (props[TIPC_NLA_PROP_WIN]) { 1975 u32 win; 1976 1977 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); 1978 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN)) 1979 return -EINVAL; 1980 } 1981 1982 return 0; 1983 } 1984 1985 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s) 1986 { 1987 int i; 1988 struct nlattr *stats; 1989 1990 struct nla_map { 1991 u32 key; 1992 u32 val; 1993 }; 1994 1995 struct nla_map map[] = { 1996 {TIPC_NLA_STATS_RX_INFO, 0}, 1997 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments}, 1998 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented}, 1999 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles}, 2000 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled}, 2001 {TIPC_NLA_STATS_TX_INFO, 0}, 2002 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments}, 2003 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented}, 2004 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles}, 2005 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled}, 2006 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ? 2007 s->msg_length_counts : 1}, 2008 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts}, 2009 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total}, 2010 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]}, 2011 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]}, 2012 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]}, 2013 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]}, 2014 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]}, 2015 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]}, 2016 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]}, 2017 {TIPC_NLA_STATS_RX_STATES, s->recv_states}, 2018 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes}, 2019 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks}, 2020 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv}, 2021 {TIPC_NLA_STATS_TX_STATES, s->sent_states}, 2022 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes}, 2023 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks}, 2024 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks}, 2025 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted}, 2026 {TIPC_NLA_STATS_DUPLICATES, s->duplicates}, 2027 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs}, 2028 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz}, 2029 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ? 2030 (s->accu_queue_sz / s->queue_sz_counts) : 0} 2031 }; 2032 2033 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS); 2034 if (!stats) 2035 return -EMSGSIZE; 2036 2037 for (i = 0; i < ARRAY_SIZE(map); i++) 2038 if (nla_put_u32(skb, map[i].key, map[i].val)) 2039 goto msg_full; 2040 2041 nla_nest_end(skb, stats); 2042 2043 return 0; 2044 msg_full: 2045 nla_nest_cancel(skb, stats); 2046 2047 return -EMSGSIZE; 2048 } 2049 2050 /* Caller should hold appropriate locks to protect the link */ 2051 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg, 2052 struct tipc_link *link, int nlflags) 2053 { 2054 u32 self = tipc_own_addr(net); 2055 struct nlattr *attrs; 2056 struct nlattr *prop; 2057 void *hdr; 2058 int err; 2059 2060 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 2061 nlflags, TIPC_NL_LINK_GET); 2062 if (!hdr) 2063 return -EMSGSIZE; 2064 2065 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK); 2066 if (!attrs) 2067 goto msg_full; 2068 2069 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name)) 2070 goto attr_msg_full; 2071 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self))) 2072 goto attr_msg_full; 2073 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu)) 2074 goto attr_msg_full; 2075 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts)) 2076 goto attr_msg_full; 2077 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts)) 2078 goto attr_msg_full; 2079 2080 if (tipc_link_is_up(link)) 2081 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 2082 goto attr_msg_full; 2083 if (link->active) 2084 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE)) 2085 goto attr_msg_full; 2086 2087 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP); 2088 if (!prop) 2089 goto attr_msg_full; 2090 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 2091 goto prop_msg_full; 2092 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance)) 2093 goto prop_msg_full; 2094 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, 2095 link->window)) 2096 goto prop_msg_full; 2097 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 2098 goto prop_msg_full; 2099 nla_nest_end(msg->skb, prop); 2100 2101 err = __tipc_nl_add_stats(msg->skb, &link->stats); 2102 if (err) 2103 goto attr_msg_full; 2104 2105 nla_nest_end(msg->skb, attrs); 2106 genlmsg_end(msg->skb, hdr); 2107 2108 return 0; 2109 2110 prop_msg_full: 2111 nla_nest_cancel(msg->skb, prop); 2112 attr_msg_full: 2113 nla_nest_cancel(msg->skb, attrs); 2114 msg_full: 2115 genlmsg_cancel(msg->skb, hdr); 2116 2117 return -EMSGSIZE; 2118 } 2119 2120 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb, 2121 struct tipc_stats *stats) 2122 { 2123 int i; 2124 struct nlattr *nest; 2125 2126 struct nla_map { 2127 __u32 key; 2128 __u32 val; 2129 }; 2130 2131 struct nla_map map[] = { 2132 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts}, 2133 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments}, 2134 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented}, 2135 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles}, 2136 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled}, 2137 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts}, 2138 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments}, 2139 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented}, 2140 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles}, 2141 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled}, 2142 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks}, 2143 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv}, 2144 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks}, 2145 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks}, 2146 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted}, 2147 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates}, 2148 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs}, 2149 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz}, 2150 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ? 2151 (stats->accu_queue_sz / stats->queue_sz_counts) : 0} 2152 }; 2153 2154 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS); 2155 if (!nest) 2156 return -EMSGSIZE; 2157 2158 for (i = 0; i < ARRAY_SIZE(map); i++) 2159 if (nla_put_u32(skb, map[i].key, map[i].val)) 2160 goto msg_full; 2161 2162 nla_nest_end(skb, nest); 2163 2164 return 0; 2165 msg_full: 2166 nla_nest_cancel(skb, nest); 2167 2168 return -EMSGSIZE; 2169 } 2170 2171 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg) 2172 { 2173 int err; 2174 void *hdr; 2175 struct nlattr *attrs; 2176 struct nlattr *prop; 2177 struct tipc_net *tn = net_generic(net, tipc_net_id); 2178 struct tipc_link *bcl = tn->bcl; 2179 2180 if (!bcl) 2181 return 0; 2182 2183 tipc_bcast_lock(net); 2184 2185 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 2186 NLM_F_MULTI, TIPC_NL_LINK_GET); 2187 if (!hdr) { 2188 tipc_bcast_unlock(net); 2189 return -EMSGSIZE; 2190 } 2191 2192 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK); 2193 if (!attrs) 2194 goto msg_full; 2195 2196 /* The broadcast link is always up */ 2197 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 2198 goto attr_msg_full; 2199 2200 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST)) 2201 goto attr_msg_full; 2202 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name)) 2203 goto attr_msg_full; 2204 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0)) 2205 goto attr_msg_full; 2206 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0)) 2207 goto attr_msg_full; 2208 2209 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP); 2210 if (!prop) 2211 goto attr_msg_full; 2212 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window)) 2213 goto prop_msg_full; 2214 nla_nest_end(msg->skb, prop); 2215 2216 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats); 2217 if (err) 2218 goto attr_msg_full; 2219 2220 tipc_bcast_unlock(net); 2221 nla_nest_end(msg->skb, attrs); 2222 genlmsg_end(msg->skb, hdr); 2223 2224 return 0; 2225 2226 prop_msg_full: 2227 nla_nest_cancel(msg->skb, prop); 2228 attr_msg_full: 2229 nla_nest_cancel(msg->skb, attrs); 2230 msg_full: 2231 tipc_bcast_unlock(net); 2232 genlmsg_cancel(msg->skb, hdr); 2233 2234 return -EMSGSIZE; 2235 } 2236 2237 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol, 2238 struct sk_buff_head *xmitq) 2239 { 2240 l->tolerance = tol; 2241 if (l->bc_rcvlink) 2242 l->bc_rcvlink->tolerance = tol; 2243 if (link_is_up(l)) 2244 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq); 2245 } 2246 2247 void tipc_link_set_prio(struct tipc_link *l, u32 prio, 2248 struct sk_buff_head *xmitq) 2249 { 2250 l->priority = prio; 2251 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq); 2252 } 2253 2254 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit) 2255 { 2256 l->abort_limit = limit; 2257 } 2258