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