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 int tipc_link_is_active(struct tipc_link *l) 301 { 302 return l->active; 303 } 304 305 void tipc_link_set_active(struct tipc_link *l, bool active) 306 { 307 l->active = active; 308 } 309 310 u32 tipc_link_id(struct tipc_link *l) 311 { 312 return l->peer_bearer_id << 16 | l->bearer_id; 313 } 314 315 int tipc_link_window(struct tipc_link *l) 316 { 317 return l->window; 318 } 319 320 int tipc_link_prio(struct tipc_link *l) 321 { 322 return l->priority; 323 } 324 325 unsigned long tipc_link_tolerance(struct tipc_link *l) 326 { 327 return l->tolerance; 328 } 329 330 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l) 331 { 332 return l->inputq; 333 } 334 335 char tipc_link_plane(struct tipc_link *l) 336 { 337 return l->net_plane; 338 } 339 340 void tipc_link_update_caps(struct tipc_link *l, u16 capabilities) 341 { 342 l->peer_caps = capabilities; 343 } 344 345 void tipc_link_add_bc_peer(struct tipc_link *snd_l, 346 struct tipc_link *uc_l, 347 struct sk_buff_head *xmitq) 348 { 349 struct tipc_link *rcv_l = uc_l->bc_rcvlink; 350 351 snd_l->ackers++; 352 rcv_l->acked = snd_l->snd_nxt - 1; 353 snd_l->state = LINK_ESTABLISHED; 354 tipc_link_build_bc_init_msg(uc_l, xmitq); 355 } 356 357 void tipc_link_remove_bc_peer(struct tipc_link *snd_l, 358 struct tipc_link *rcv_l, 359 struct sk_buff_head *xmitq) 360 { 361 u16 ack = snd_l->snd_nxt - 1; 362 363 snd_l->ackers--; 364 rcv_l->bc_peer_is_up = true; 365 rcv_l->state = LINK_ESTABLISHED; 366 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq); 367 tipc_link_reset(rcv_l); 368 rcv_l->state = LINK_RESET; 369 if (!snd_l->ackers) { 370 tipc_link_reset(snd_l); 371 snd_l->state = LINK_RESET; 372 __skb_queue_purge(xmitq); 373 } 374 } 375 376 int tipc_link_bc_peers(struct tipc_link *l) 377 { 378 return l->ackers; 379 } 380 381 u16 link_bc_rcv_gap(struct tipc_link *l) 382 { 383 struct sk_buff *skb = skb_peek(&l->deferdq); 384 u16 gap = 0; 385 386 if (more(l->snd_nxt, l->rcv_nxt)) 387 gap = l->snd_nxt - l->rcv_nxt; 388 if (skb) 389 gap = buf_seqno(skb) - l->rcv_nxt; 390 return gap; 391 } 392 393 void tipc_link_set_mtu(struct tipc_link *l, int mtu) 394 { 395 l->mtu = mtu; 396 } 397 398 int tipc_link_mtu(struct tipc_link *l) 399 { 400 return l->mtu; 401 } 402 403 u16 tipc_link_rcv_nxt(struct tipc_link *l) 404 { 405 return l->rcv_nxt; 406 } 407 408 u16 tipc_link_acked(struct tipc_link *l) 409 { 410 return l->acked; 411 } 412 413 char *tipc_link_name(struct tipc_link *l) 414 { 415 return l->name; 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 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 __skb_queue_purge(&l->transmq); 850 __skb_queue_purge(&l->deferdq); 851 skb_queue_splice_init(&l->wakeupq, l->inputq); 852 __skb_queue_purge(&l->backlogq); 853 l->backlog[TIPC_LOW_IMPORTANCE].len = 0; 854 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0; 855 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0; 856 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0; 857 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0; 858 kfree_skb(l->reasm_buf); 859 kfree_skb(l->failover_reasm_skb); 860 l->reasm_buf = NULL; 861 l->failover_reasm_skb = NULL; 862 l->rcv_unacked = 0; 863 l->snd_nxt = 1; 864 l->rcv_nxt = 1; 865 l->snd_nxt_state = 1; 866 l->rcv_nxt_state = 1; 867 l->acked = 0; 868 l->silent_intv_cnt = 0; 869 l->rst_cnt = 0; 870 l->stale_cnt = 0; 871 l->bc_peer_is_up = false; 872 memset(&l->mon_state, 0, sizeof(l->mon_state)); 873 tipc_link_reset_stats(l); 874 } 875 876 /** 877 * tipc_link_xmit(): enqueue buffer list according to queue situation 878 * @link: link to use 879 * @list: chain of buffers containing message 880 * @xmitq: returned list of packets to be sent by caller 881 * 882 * Consumes the buffer chain. 883 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS 884 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted 885 */ 886 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list, 887 struct sk_buff_head *xmitq) 888 { 889 struct tipc_msg *hdr = buf_msg(skb_peek(list)); 890 unsigned int maxwin = l->window; 891 int imp = msg_importance(hdr); 892 unsigned int mtu = l->mtu; 893 u16 ack = l->rcv_nxt - 1; 894 u16 seqno = l->snd_nxt; 895 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 896 struct sk_buff_head *transmq = &l->transmq; 897 struct sk_buff_head *backlogq = &l->backlogq; 898 struct sk_buff *skb, *_skb, *bskb; 899 int pkt_cnt = skb_queue_len(list); 900 int rc = 0; 901 902 if (unlikely(msg_size(hdr) > mtu)) { 903 skb_queue_purge(list); 904 return -EMSGSIZE; 905 } 906 907 /* Allow oversubscription of one data msg per source at congestion */ 908 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) { 909 if (imp == TIPC_SYSTEM_IMPORTANCE) { 910 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name); 911 return -ENOBUFS; 912 } 913 rc = link_schedule_user(l, hdr); 914 } 915 916 if (pkt_cnt > 1) { 917 l->stats.sent_fragmented++; 918 l->stats.sent_fragments += pkt_cnt; 919 } 920 921 /* Prepare each packet for sending, and add to relevant queue: */ 922 while (skb_queue_len(list)) { 923 skb = skb_peek(list); 924 hdr = buf_msg(skb); 925 msg_set_seqno(hdr, seqno); 926 msg_set_ack(hdr, ack); 927 msg_set_bcast_ack(hdr, bc_ack); 928 929 if (likely(skb_queue_len(transmq) < maxwin)) { 930 _skb = skb_clone(skb, GFP_ATOMIC); 931 if (!_skb) { 932 skb_queue_purge(list); 933 return -ENOBUFS; 934 } 935 __skb_dequeue(list); 936 __skb_queue_tail(transmq, skb); 937 __skb_queue_tail(xmitq, _skb); 938 TIPC_SKB_CB(skb)->ackers = l->ackers; 939 l->rcv_unacked = 0; 940 l->stats.sent_pkts++; 941 seqno++; 942 continue; 943 } 944 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) { 945 kfree_skb(__skb_dequeue(list)); 946 l->stats.sent_bundled++; 947 continue; 948 } 949 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) { 950 kfree_skb(__skb_dequeue(list)); 951 __skb_queue_tail(backlogq, bskb); 952 l->backlog[msg_importance(buf_msg(bskb))].len++; 953 l->stats.sent_bundled++; 954 l->stats.sent_bundles++; 955 continue; 956 } 957 l->backlog[imp].len += skb_queue_len(list); 958 skb_queue_splice_tail_init(list, backlogq); 959 } 960 l->snd_nxt = seqno; 961 return rc; 962 } 963 964 void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq) 965 { 966 struct sk_buff *skb, *_skb; 967 struct tipc_msg *hdr; 968 u16 seqno = l->snd_nxt; 969 u16 ack = l->rcv_nxt - 1; 970 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 971 972 while (skb_queue_len(&l->transmq) < l->window) { 973 skb = skb_peek(&l->backlogq); 974 if (!skb) 975 break; 976 _skb = skb_clone(skb, GFP_ATOMIC); 977 if (!_skb) 978 break; 979 __skb_dequeue(&l->backlogq); 980 hdr = buf_msg(skb); 981 l->backlog[msg_importance(hdr)].len--; 982 __skb_queue_tail(&l->transmq, skb); 983 __skb_queue_tail(xmitq, _skb); 984 TIPC_SKB_CB(skb)->ackers = l->ackers; 985 msg_set_seqno(hdr, seqno); 986 msg_set_ack(hdr, ack); 987 msg_set_bcast_ack(hdr, bc_ack); 988 l->rcv_unacked = 0; 989 l->stats.sent_pkts++; 990 seqno++; 991 } 992 l->snd_nxt = seqno; 993 } 994 995 static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb) 996 { 997 struct tipc_msg *hdr = buf_msg(skb); 998 999 pr_warn("Retransmission failure on link <%s>\n", l->name); 1000 link_print(l, "State of link "); 1001 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n", 1002 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr)); 1003 pr_info("sqno %u, prev: %x, src: %x\n", 1004 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr)); 1005 } 1006 1007 /* tipc_link_retrans() - retransmit one or more packets 1008 * @l: the link to transmit on 1009 * @r: the receiving link ordering the retransmit. Same as l if unicast 1010 * @from: retransmit from (inclusive) this sequence number 1011 * @to: retransmit to (inclusive) this sequence number 1012 * xmitq: queue for accumulating the retransmitted packets 1013 */ 1014 int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r, 1015 u16 from, u16 to, struct sk_buff_head *xmitq) 1016 { 1017 struct sk_buff *_skb, *skb = skb_peek(&l->transmq); 1018 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 1019 u16 ack = l->rcv_nxt - 1; 1020 struct tipc_msg *hdr; 1021 1022 if (!skb) 1023 return 0; 1024 1025 /* Detect repeated retransmit failures on same packet */ 1026 if (r->last_retransm != buf_seqno(skb)) { 1027 r->last_retransm = buf_seqno(skb); 1028 r->stale_limit = jiffies + msecs_to_jiffies(l->tolerance); 1029 } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) { 1030 link_retransmit_failure(l, skb); 1031 if (link_is_bc_sndlink(l)) 1032 return TIPC_LINK_DOWN_EVT; 1033 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1034 } 1035 1036 skb_queue_walk(&l->transmq, skb) { 1037 hdr = buf_msg(skb); 1038 if (less(msg_seqno(hdr), from)) 1039 continue; 1040 if (more(msg_seqno(hdr), to)) 1041 break; 1042 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC); 1043 if (!_skb) 1044 return 0; 1045 hdr = buf_msg(_skb); 1046 msg_set_ack(hdr, ack); 1047 msg_set_bcast_ack(hdr, bc_ack); 1048 _skb->priority = TC_PRIO_CONTROL; 1049 __skb_queue_tail(xmitq, _skb); 1050 l->stats.retransmitted++; 1051 } 1052 return 0; 1053 } 1054 1055 /* tipc_data_input - deliver data and name distr msgs to upper layer 1056 * 1057 * Consumes buffer if message is of right type 1058 * Node lock must be held 1059 */ 1060 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb, 1061 struct sk_buff_head *inputq) 1062 { 1063 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq; 1064 struct tipc_msg *hdr = buf_msg(skb); 1065 1066 switch (msg_user(hdr)) { 1067 case TIPC_LOW_IMPORTANCE: 1068 case TIPC_MEDIUM_IMPORTANCE: 1069 case TIPC_HIGH_IMPORTANCE: 1070 case TIPC_CRITICAL_IMPORTANCE: 1071 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) { 1072 skb_queue_tail(mc_inputq, skb); 1073 return true; 1074 } 1075 /* else: fall through */ 1076 case CONN_MANAGER: 1077 skb_queue_tail(inputq, skb); 1078 return true; 1079 case GROUP_PROTOCOL: 1080 skb_queue_tail(mc_inputq, skb); 1081 return true; 1082 case NAME_DISTRIBUTOR: 1083 l->bc_rcvlink->state = LINK_ESTABLISHED; 1084 skb_queue_tail(l->namedq, skb); 1085 return true; 1086 case MSG_BUNDLER: 1087 case TUNNEL_PROTOCOL: 1088 case MSG_FRAGMENTER: 1089 case BCAST_PROTOCOL: 1090 return false; 1091 default: 1092 pr_warn("Dropping received illegal msg type\n"); 1093 kfree_skb(skb); 1094 return false; 1095 }; 1096 } 1097 1098 /* tipc_link_input - process packet that has passed link protocol check 1099 * 1100 * Consumes buffer 1101 */ 1102 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb, 1103 struct sk_buff_head *inputq) 1104 { 1105 struct tipc_msg *hdr = buf_msg(skb); 1106 struct sk_buff **reasm_skb = &l->reasm_buf; 1107 struct sk_buff *iskb; 1108 struct sk_buff_head tmpq; 1109 int usr = msg_user(hdr); 1110 int rc = 0; 1111 int pos = 0; 1112 int ipos = 0; 1113 1114 if (unlikely(usr == TUNNEL_PROTOCOL)) { 1115 if (msg_type(hdr) == SYNCH_MSG) { 1116 __skb_queue_purge(&l->deferdq); 1117 goto drop; 1118 } 1119 if (!tipc_msg_extract(skb, &iskb, &ipos)) 1120 return rc; 1121 kfree_skb(skb); 1122 skb = iskb; 1123 hdr = buf_msg(skb); 1124 if (less(msg_seqno(hdr), l->drop_point)) 1125 goto drop; 1126 if (tipc_data_input(l, skb, inputq)) 1127 return rc; 1128 usr = msg_user(hdr); 1129 reasm_skb = &l->failover_reasm_skb; 1130 } 1131 1132 if (usr == MSG_BUNDLER) { 1133 skb_queue_head_init(&tmpq); 1134 l->stats.recv_bundles++; 1135 l->stats.recv_bundled += msg_msgcnt(hdr); 1136 while (tipc_msg_extract(skb, &iskb, &pos)) 1137 tipc_data_input(l, iskb, &tmpq); 1138 tipc_skb_queue_splice_tail(&tmpq, inputq); 1139 return 0; 1140 } else if (usr == MSG_FRAGMENTER) { 1141 l->stats.recv_fragments++; 1142 if (tipc_buf_append(reasm_skb, &skb)) { 1143 l->stats.recv_fragmented++; 1144 tipc_data_input(l, skb, inputq); 1145 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) { 1146 pr_warn_ratelimited("Unable to build fragment list\n"); 1147 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1148 } 1149 return 0; 1150 } else if (usr == BCAST_PROTOCOL) { 1151 tipc_bcast_lock(l->net); 1152 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr); 1153 tipc_bcast_unlock(l->net); 1154 } 1155 drop: 1156 kfree_skb(skb); 1157 return 0; 1158 } 1159 1160 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked) 1161 { 1162 bool released = false; 1163 struct sk_buff *skb, *tmp; 1164 1165 skb_queue_walk_safe(&l->transmq, skb, tmp) { 1166 if (more(buf_seqno(skb), acked)) 1167 break; 1168 __skb_unlink(skb, &l->transmq); 1169 kfree_skb(skb); 1170 released = true; 1171 } 1172 return released; 1173 } 1174 1175 /* tipc_link_build_state_msg: prepare link state message for transmission 1176 * 1177 * Note that sending of broadcast ack is coordinated among nodes, to reduce 1178 * risk of ack storms towards the sender 1179 */ 1180 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 1181 { 1182 if (!l) 1183 return 0; 1184 1185 /* Broadcast ACK must be sent via a unicast link => defer to caller */ 1186 if (link_is_bc_rcvlink(l)) { 1187 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf) 1188 return 0; 1189 l->rcv_unacked = 0; 1190 1191 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */ 1192 l->snd_nxt = l->rcv_nxt; 1193 return TIPC_LINK_SND_STATE; 1194 } 1195 1196 /* Unicast ACK */ 1197 l->rcv_unacked = 0; 1198 l->stats.sent_acks++; 1199 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq); 1200 return 0; 1201 } 1202 1203 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message 1204 */ 1205 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 1206 { 1207 int mtyp = RESET_MSG; 1208 struct sk_buff *skb; 1209 1210 if (l->state == LINK_ESTABLISHING) 1211 mtyp = ACTIVATE_MSG; 1212 1213 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq); 1214 1215 /* Inform peer that this endpoint is going down if applicable */ 1216 skb = skb_peek_tail(xmitq); 1217 if (skb && (l->state == LINK_RESET)) 1218 msg_set_peer_stopping(buf_msg(skb), 1); 1219 } 1220 1221 /* tipc_link_build_nack_msg: prepare link nack message for transmission 1222 * Note that sending of broadcast NACK is coordinated among nodes, to 1223 * reduce the risk of NACK storms towards the sender 1224 */ 1225 static int tipc_link_build_nack_msg(struct tipc_link *l, 1226 struct sk_buff_head *xmitq) 1227 { 1228 u32 def_cnt = ++l->stats.deferred_recv; 1229 int match1, match2; 1230 1231 if (link_is_bc_rcvlink(l)) { 1232 match1 = def_cnt & 0xf; 1233 match2 = tipc_own_addr(l->net) & 0xf; 1234 if (match1 == match2) 1235 return TIPC_LINK_SND_STATE; 1236 return 0; 1237 } 1238 1239 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV)) 1240 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq); 1241 return 0; 1242 } 1243 1244 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node 1245 * @l: the link that should handle the message 1246 * @skb: TIPC packet 1247 * @xmitq: queue to place packets to be sent after this call 1248 */ 1249 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, 1250 struct sk_buff_head *xmitq) 1251 { 1252 struct sk_buff_head *defq = &l->deferdq; 1253 struct tipc_msg *hdr; 1254 u16 seqno, rcv_nxt, win_lim; 1255 int rc = 0; 1256 1257 do { 1258 hdr = buf_msg(skb); 1259 seqno = msg_seqno(hdr); 1260 rcv_nxt = l->rcv_nxt; 1261 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN; 1262 1263 /* Verify and update link state */ 1264 if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) 1265 return tipc_link_proto_rcv(l, skb, xmitq); 1266 1267 if (unlikely(!link_is_up(l))) { 1268 if (l->state == LINK_ESTABLISHING) 1269 rc = TIPC_LINK_UP_EVT; 1270 goto drop; 1271 } 1272 1273 /* Don't send probe at next timeout expiration */ 1274 l->silent_intv_cnt = 0; 1275 1276 /* Drop if outside receive window */ 1277 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) { 1278 l->stats.duplicates++; 1279 goto drop; 1280 } 1281 1282 /* Forward queues and wake up waiting users */ 1283 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) { 1284 l->stale_cnt = 0; 1285 tipc_link_advance_backlog(l, xmitq); 1286 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1287 link_prepare_wakeup(l); 1288 } 1289 1290 /* Defer delivery if sequence gap */ 1291 if (unlikely(seqno != rcv_nxt)) { 1292 __tipc_skb_queue_sorted(defq, seqno, skb); 1293 rc |= tipc_link_build_nack_msg(l, xmitq); 1294 break; 1295 } 1296 1297 /* Deliver packet */ 1298 l->rcv_nxt++; 1299 l->stats.recv_pkts++; 1300 if (!tipc_data_input(l, skb, l->inputq)) 1301 rc |= tipc_link_input(l, skb, l->inputq); 1302 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN)) 1303 rc |= tipc_link_build_state_msg(l, xmitq); 1304 if (unlikely(rc & ~TIPC_LINK_SND_STATE)) 1305 break; 1306 } while ((skb = __skb_dequeue(defq))); 1307 1308 return rc; 1309 drop: 1310 kfree_skb(skb); 1311 return rc; 1312 } 1313 1314 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, 1315 bool probe_reply, u16 rcvgap, 1316 int tolerance, int priority, 1317 struct sk_buff_head *xmitq) 1318 { 1319 struct tipc_link *bcl = l->bc_rcvlink; 1320 struct sk_buff *skb; 1321 struct tipc_msg *hdr; 1322 struct sk_buff_head *dfq = &l->deferdq; 1323 bool node_up = link_is_up(bcl); 1324 struct tipc_mon_state *mstate = &l->mon_state; 1325 int dlen = 0; 1326 void *data; 1327 1328 /* Don't send protocol message during reset or link failover */ 1329 if (tipc_link_is_blocked(l)) 1330 return; 1331 1332 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG)) 1333 return; 1334 1335 if (!skb_queue_empty(dfq)) 1336 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt; 1337 1338 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE, 1339 tipc_max_domain_size, l->addr, 1340 tipc_own_addr(l->net), 0, 0, 0); 1341 if (!skb) 1342 return; 1343 1344 hdr = buf_msg(skb); 1345 data = msg_data(hdr); 1346 msg_set_session(hdr, l->session); 1347 msg_set_bearer_id(hdr, l->bearer_id); 1348 msg_set_net_plane(hdr, l->net_plane); 1349 msg_set_next_sent(hdr, l->snd_nxt); 1350 msg_set_ack(hdr, l->rcv_nxt - 1); 1351 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1); 1352 msg_set_bc_ack_invalid(hdr, !node_up); 1353 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1354 msg_set_link_tolerance(hdr, tolerance); 1355 msg_set_linkprio(hdr, priority); 1356 msg_set_redundant_link(hdr, node_up); 1357 msg_set_seq_gap(hdr, 0); 1358 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2); 1359 1360 if (mtyp == STATE_MSG) { 1361 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO) 1362 msg_set_seqno(hdr, l->snd_nxt_state++); 1363 msg_set_seq_gap(hdr, rcvgap); 1364 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl)); 1365 msg_set_probe(hdr, probe); 1366 msg_set_is_keepalive(hdr, probe || probe_reply); 1367 tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id); 1368 msg_set_size(hdr, INT_H_SIZE + dlen); 1369 skb_trim(skb, INT_H_SIZE + dlen); 1370 l->stats.sent_states++; 1371 l->rcv_unacked = 0; 1372 } else { 1373 /* RESET_MSG or ACTIVATE_MSG */ 1374 msg_set_max_pkt(hdr, l->advertised_mtu); 1375 strcpy(data, l->if_name); 1376 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME); 1377 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME); 1378 } 1379 if (probe) 1380 l->stats.sent_probes++; 1381 if (rcvgap) 1382 l->stats.sent_nacks++; 1383 skb->priority = TC_PRIO_CONTROL; 1384 __skb_queue_tail(xmitq, skb); 1385 } 1386 1387 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets 1388 * with contents of the link's transmit and backlog queues. 1389 */ 1390 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, 1391 int mtyp, struct sk_buff_head *xmitq) 1392 { 1393 struct sk_buff *skb, *tnlskb; 1394 struct tipc_msg *hdr, tnlhdr; 1395 struct sk_buff_head *queue = &l->transmq; 1396 struct sk_buff_head tmpxq, tnlq; 1397 u16 pktlen, pktcnt, seqno = l->snd_nxt; 1398 1399 if (!tnl) 1400 return; 1401 1402 skb_queue_head_init(&tnlq); 1403 skb_queue_head_init(&tmpxq); 1404 1405 /* At least one packet required for safe algorithm => add dummy */ 1406 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG, 1407 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net), 1408 0, 0, TIPC_ERR_NO_PORT); 1409 if (!skb) { 1410 pr_warn("%sunable to create tunnel packet\n", link_co_err); 1411 return; 1412 } 1413 skb_queue_tail(&tnlq, skb); 1414 tipc_link_xmit(l, &tnlq, &tmpxq); 1415 __skb_queue_purge(&tmpxq); 1416 1417 /* Initialize reusable tunnel packet header */ 1418 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL, 1419 mtyp, INT_H_SIZE, l->addr); 1420 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq); 1421 msg_set_msgcnt(&tnlhdr, pktcnt); 1422 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id); 1423 tnl: 1424 /* Wrap each packet into a tunnel packet */ 1425 skb_queue_walk(queue, skb) { 1426 hdr = buf_msg(skb); 1427 if (queue == &l->backlogq) 1428 msg_set_seqno(hdr, seqno++); 1429 pktlen = msg_size(hdr); 1430 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE); 1431 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC); 1432 if (!tnlskb) { 1433 pr_warn("%sunable to send packet\n", link_co_err); 1434 return; 1435 } 1436 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE); 1437 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen); 1438 __skb_queue_tail(&tnlq, tnlskb); 1439 } 1440 if (queue != &l->backlogq) { 1441 queue = &l->backlogq; 1442 goto tnl; 1443 } 1444 1445 tipc_link_xmit(tnl, &tnlq, xmitq); 1446 1447 if (mtyp == FAILOVER_MSG) { 1448 tnl->drop_point = l->rcv_nxt; 1449 tnl->failover_reasm_skb = l->reasm_buf; 1450 l->reasm_buf = NULL; 1451 } 1452 } 1453 1454 /* tipc_link_validate_msg(): validate message against current link state 1455 * Returns true if message should be accepted, otherwise false 1456 */ 1457 bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr) 1458 { 1459 u16 curr_session = l->peer_session; 1460 u16 session = msg_session(hdr); 1461 int mtyp = msg_type(hdr); 1462 1463 if (msg_user(hdr) != LINK_PROTOCOL) 1464 return true; 1465 1466 switch (mtyp) { 1467 case RESET_MSG: 1468 if (!l->in_session) 1469 return true; 1470 /* Accept only RESET with new session number */ 1471 return more(session, curr_session); 1472 case ACTIVATE_MSG: 1473 if (!l->in_session) 1474 return true; 1475 /* Accept only ACTIVATE with new or current session number */ 1476 return !less(session, curr_session); 1477 case STATE_MSG: 1478 /* Accept only STATE with current session number */ 1479 if (!l->in_session) 1480 return false; 1481 if (session != curr_session) 1482 return false; 1483 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO)) 1484 return true; 1485 /* Accept only STATE with new sequence number */ 1486 return !less(msg_seqno(hdr), l->rcv_nxt_state); 1487 default: 1488 return false; 1489 } 1490 } 1491 1492 /* tipc_link_proto_rcv(): receive link level protocol message : 1493 * Note that network plane id propagates through the network, and may 1494 * change at any time. The node with lowest numerical id determines 1495 * network plane 1496 */ 1497 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, 1498 struct sk_buff_head *xmitq) 1499 { 1500 struct tipc_msg *hdr = buf_msg(skb); 1501 u16 rcvgap = 0; 1502 u16 ack = msg_ack(hdr); 1503 u16 gap = msg_seq_gap(hdr); 1504 u16 peers_snd_nxt = msg_next_sent(hdr); 1505 u16 peers_tol = msg_link_tolerance(hdr); 1506 u16 peers_prio = msg_linkprio(hdr); 1507 u16 rcv_nxt = l->rcv_nxt; 1508 u16 dlen = msg_data_sz(hdr); 1509 int mtyp = msg_type(hdr); 1510 bool reply = msg_probe(hdr); 1511 void *data; 1512 char *if_name; 1513 int rc = 0; 1514 1515 if (tipc_link_is_blocked(l) || !xmitq) 1516 goto exit; 1517 1518 if (tipc_own_addr(l->net) > msg_prevnode(hdr)) 1519 l->net_plane = msg_net_plane(hdr); 1520 1521 skb_linearize(skb); 1522 hdr = buf_msg(skb); 1523 data = msg_data(hdr); 1524 1525 if (!tipc_link_validate_msg(l, hdr)) 1526 goto exit; 1527 1528 switch (mtyp) { 1529 case RESET_MSG: 1530 case ACTIVATE_MSG: 1531 /* Complete own link name with peer's interface name */ 1532 if_name = strrchr(l->name, ':') + 1; 1533 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME) 1534 break; 1535 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME) 1536 break; 1537 strncpy(if_name, data, TIPC_MAX_IF_NAME); 1538 1539 /* Update own tolerance if peer indicates a non-zero value */ 1540 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) 1541 l->tolerance = peers_tol; 1542 1543 /* Update own priority if peer's priority is higher */ 1544 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI)) 1545 l->priority = peers_prio; 1546 1547 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */ 1548 if (msg_peer_stopping(hdr)) 1549 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1550 else if ((mtyp == RESET_MSG) || !link_is_up(l)) 1551 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); 1552 1553 /* ACTIVATE_MSG takes up link if it was already locally reset */ 1554 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING)) 1555 rc = TIPC_LINK_UP_EVT; 1556 1557 l->peer_session = msg_session(hdr); 1558 l->in_session = true; 1559 l->peer_bearer_id = msg_bearer_id(hdr); 1560 if (l->mtu > msg_max_pkt(hdr)) 1561 l->mtu = msg_max_pkt(hdr); 1562 break; 1563 1564 case STATE_MSG: 1565 l->rcv_nxt_state = msg_seqno(hdr) + 1; 1566 1567 /* Update own tolerance if peer indicates a non-zero value */ 1568 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) 1569 l->tolerance = peers_tol; 1570 1571 /* Update own prio if peer indicates a different value */ 1572 if ((peers_prio != l->priority) && 1573 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) { 1574 l->priority = peers_prio; 1575 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1576 } 1577 1578 l->silent_intv_cnt = 0; 1579 l->stats.recv_states++; 1580 if (msg_probe(hdr)) 1581 l->stats.recv_probes++; 1582 1583 if (!link_is_up(l)) { 1584 if (l->state == LINK_ESTABLISHING) 1585 rc = TIPC_LINK_UP_EVT; 1586 break; 1587 } 1588 tipc_mon_rcv(l->net, data, dlen, l->addr, 1589 &l->mon_state, l->bearer_id); 1590 1591 /* Send NACK if peer has sent pkts we haven't received yet */ 1592 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l)) 1593 rcvgap = peers_snd_nxt - l->rcv_nxt; 1594 if (rcvgap || reply) 1595 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply, 1596 rcvgap, 0, 0, xmitq); 1597 tipc_link_release_pkts(l, ack); 1598 1599 /* If NACK, retransmit will now start at right position */ 1600 if (gap) { 1601 rc = tipc_link_retrans(l, l, ack + 1, ack + gap, xmitq); 1602 l->stats.recv_nacks++; 1603 } 1604 1605 tipc_link_advance_backlog(l, xmitq); 1606 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1607 link_prepare_wakeup(l); 1608 } 1609 exit: 1610 kfree_skb(skb); 1611 return rc; 1612 } 1613 1614 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message 1615 */ 1616 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast, 1617 u16 peers_snd_nxt, 1618 struct sk_buff_head *xmitq) 1619 { 1620 struct sk_buff *skb; 1621 struct tipc_msg *hdr; 1622 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq); 1623 u16 ack = l->rcv_nxt - 1; 1624 u16 gap_to = peers_snd_nxt - 1; 1625 1626 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, 1627 0, l->addr, tipc_own_addr(l->net), 0, 0, 0); 1628 if (!skb) 1629 return false; 1630 hdr = buf_msg(skb); 1631 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1632 msg_set_bcast_ack(hdr, ack); 1633 msg_set_bcgap_after(hdr, ack); 1634 if (dfrd_skb) 1635 gap_to = buf_seqno(dfrd_skb) - 1; 1636 msg_set_bcgap_to(hdr, gap_to); 1637 msg_set_non_seq(hdr, bcast); 1638 __skb_queue_tail(xmitq, skb); 1639 return true; 1640 } 1641 1642 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints. 1643 * 1644 * Give a newly added peer node the sequence number where it should 1645 * start receiving and acking broadcast packets. 1646 */ 1647 static void tipc_link_build_bc_init_msg(struct tipc_link *l, 1648 struct sk_buff_head *xmitq) 1649 { 1650 struct sk_buff_head list; 1651 1652 __skb_queue_head_init(&list); 1653 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list)) 1654 return; 1655 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true); 1656 tipc_link_xmit(l, &list, xmitq); 1657 } 1658 1659 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer 1660 */ 1661 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr) 1662 { 1663 int mtyp = msg_type(hdr); 1664 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 1665 1666 if (link_is_up(l)) 1667 return; 1668 1669 if (msg_user(hdr) == BCAST_PROTOCOL) { 1670 l->rcv_nxt = peers_snd_nxt; 1671 l->state = LINK_ESTABLISHED; 1672 return; 1673 } 1674 1675 if (l->peer_caps & TIPC_BCAST_SYNCH) 1676 return; 1677 1678 if (msg_peer_node_is_up(hdr)) 1679 return; 1680 1681 /* Compatibility: accept older, less safe initial synch data */ 1682 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG)) 1683 l->rcv_nxt = peers_snd_nxt; 1684 } 1685 1686 /* link_bc_retr eval()- check if the indicated range can be retransmitted now 1687 * - Adjust permitted range if there is overlap with previous retransmission 1688 */ 1689 static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to) 1690 { 1691 unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr); 1692 1693 if (less(*to, *from)) 1694 return false; 1695 1696 /* New retransmission request */ 1697 if ((elapsed > TIPC_BC_RETR_LIMIT) || 1698 less(*to, l->prev_from) || more(*from, l->prev_to)) { 1699 l->prev_from = *from; 1700 l->prev_to = *to; 1701 l->prev_retr = jiffies; 1702 return true; 1703 } 1704 1705 /* Inside range of previous retransmit */ 1706 if (!less(*from, l->prev_from) && !more(*to, l->prev_to)) 1707 return false; 1708 1709 /* Fully or partially outside previous range => exclude overlap */ 1710 if (less(*from, l->prev_from)) { 1711 *to = l->prev_from - 1; 1712 l->prev_from = *from; 1713 } 1714 if (more(*to, l->prev_to)) { 1715 *from = l->prev_to + 1; 1716 l->prev_to = *to; 1717 } 1718 l->prev_retr = jiffies; 1719 return true; 1720 } 1721 1722 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state 1723 */ 1724 int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr, 1725 struct sk_buff_head *xmitq) 1726 { 1727 struct tipc_link *snd_l = l->bc_sndlink; 1728 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 1729 u16 from = msg_bcast_ack(hdr) + 1; 1730 u16 to = from + msg_bc_gap(hdr) - 1; 1731 int rc = 0; 1732 1733 if (!link_is_up(l)) 1734 return rc; 1735 1736 if (!msg_peer_node_is_up(hdr)) 1737 return rc; 1738 1739 /* Open when peer ackowledges our bcast init msg (pkt #1) */ 1740 if (msg_ack(hdr)) 1741 l->bc_peer_is_up = true; 1742 1743 if (!l->bc_peer_is_up) 1744 return rc; 1745 1746 l->stats.recv_nacks++; 1747 1748 /* Ignore if peers_snd_nxt goes beyond receive window */ 1749 if (more(peers_snd_nxt, l->rcv_nxt + l->window)) 1750 return rc; 1751 1752 if (link_bc_retr_eval(snd_l, &from, &to)) 1753 rc = tipc_link_retrans(snd_l, l, from, to, xmitq); 1754 1755 l->snd_nxt = peers_snd_nxt; 1756 if (link_bc_rcv_gap(l)) 1757 rc |= TIPC_LINK_SND_STATE; 1758 1759 /* Return now if sender supports nack via STATE messages */ 1760 if (l->peer_caps & TIPC_BCAST_STATE_NACK) 1761 return rc; 1762 1763 /* Otherwise, be backwards compatible */ 1764 1765 if (!more(peers_snd_nxt, l->rcv_nxt)) { 1766 l->nack_state = BC_NACK_SND_CONDITIONAL; 1767 return 0; 1768 } 1769 1770 /* Don't NACK if one was recently sent or peeked */ 1771 if (l->nack_state == BC_NACK_SND_SUPPRESS) { 1772 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 1773 return 0; 1774 } 1775 1776 /* Conditionally delay NACK sending until next synch rcv */ 1777 if (l->nack_state == BC_NACK_SND_CONDITIONAL) { 1778 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 1779 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN) 1780 return 0; 1781 } 1782 1783 /* Send NACK now but suppress next one */ 1784 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq); 1785 l->nack_state = BC_NACK_SND_SUPPRESS; 1786 return 0; 1787 } 1788 1789 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked, 1790 struct sk_buff_head *xmitq) 1791 { 1792 struct sk_buff *skb, *tmp; 1793 struct tipc_link *snd_l = l->bc_sndlink; 1794 1795 if (!link_is_up(l) || !l->bc_peer_is_up) 1796 return; 1797 1798 if (!more(acked, l->acked)) 1799 return; 1800 1801 /* Skip over packets peer has already acked */ 1802 skb_queue_walk(&snd_l->transmq, skb) { 1803 if (more(buf_seqno(skb), l->acked)) 1804 break; 1805 } 1806 1807 /* Update/release the packets peer is acking now */ 1808 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) { 1809 if (more(buf_seqno(skb), acked)) 1810 break; 1811 if (!--TIPC_SKB_CB(skb)->ackers) { 1812 __skb_unlink(skb, &snd_l->transmq); 1813 kfree_skb(skb); 1814 } 1815 } 1816 l->acked = acked; 1817 tipc_link_advance_backlog(snd_l, xmitq); 1818 if (unlikely(!skb_queue_empty(&snd_l->wakeupq))) 1819 link_prepare_wakeup(snd_l); 1820 } 1821 1822 /* tipc_link_bc_nack_rcv(): receive broadcast nack message 1823 * This function is here for backwards compatibility, since 1824 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5. 1825 */ 1826 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb, 1827 struct sk_buff_head *xmitq) 1828 { 1829 struct tipc_msg *hdr = buf_msg(skb); 1830 u32 dnode = msg_destnode(hdr); 1831 int mtyp = msg_type(hdr); 1832 u16 acked = msg_bcast_ack(hdr); 1833 u16 from = acked + 1; 1834 u16 to = msg_bcgap_to(hdr); 1835 u16 peers_snd_nxt = to + 1; 1836 int rc = 0; 1837 1838 kfree_skb(skb); 1839 1840 if (!tipc_link_is_up(l) || !l->bc_peer_is_up) 1841 return 0; 1842 1843 if (mtyp != STATE_MSG) 1844 return 0; 1845 1846 if (dnode == tipc_own_addr(l->net)) { 1847 tipc_link_bc_ack_rcv(l, acked, xmitq); 1848 rc = tipc_link_retrans(l->bc_sndlink, l, from, to, xmitq); 1849 l->stats.recv_nacks++; 1850 return rc; 1851 } 1852 1853 /* Msg for other node => suppress own NACK at next sync if applicable */ 1854 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from)) 1855 l->nack_state = BC_NACK_SND_SUPPRESS; 1856 1857 return 0; 1858 } 1859 1860 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win) 1861 { 1862 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE); 1863 1864 l->window = win; 1865 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win); 1866 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2); 1867 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3); 1868 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4); 1869 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk; 1870 } 1871 1872 /** 1873 * link_reset_stats - reset link statistics 1874 * @l: pointer to link 1875 */ 1876 void tipc_link_reset_stats(struct tipc_link *l) 1877 { 1878 memset(&l->stats, 0, sizeof(l->stats)); 1879 } 1880 1881 static void link_print(struct tipc_link *l, const char *str) 1882 { 1883 struct sk_buff *hskb = skb_peek(&l->transmq); 1884 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1; 1885 u16 tail = l->snd_nxt - 1; 1886 1887 pr_info("%s Link <%s> state %x\n", str, l->name, l->state); 1888 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n", 1889 skb_queue_len(&l->transmq), head, tail, 1890 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt); 1891 } 1892 1893 /* Parse and validate nested (link) properties valid for media, bearer and link 1894 */ 1895 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]) 1896 { 1897 int err; 1898 1899 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop, 1900 tipc_nl_prop_policy, NULL); 1901 if (err) 1902 return err; 1903 1904 if (props[TIPC_NLA_PROP_PRIO]) { 1905 u32 prio; 1906 1907 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); 1908 if (prio > TIPC_MAX_LINK_PRI) 1909 return -EINVAL; 1910 } 1911 1912 if (props[TIPC_NLA_PROP_TOL]) { 1913 u32 tol; 1914 1915 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); 1916 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL)) 1917 return -EINVAL; 1918 } 1919 1920 if (props[TIPC_NLA_PROP_WIN]) { 1921 u32 win; 1922 1923 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); 1924 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN)) 1925 return -EINVAL; 1926 } 1927 1928 return 0; 1929 } 1930 1931 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s) 1932 { 1933 int i; 1934 struct nlattr *stats; 1935 1936 struct nla_map { 1937 u32 key; 1938 u32 val; 1939 }; 1940 1941 struct nla_map map[] = { 1942 {TIPC_NLA_STATS_RX_INFO, 0}, 1943 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments}, 1944 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented}, 1945 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles}, 1946 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled}, 1947 {TIPC_NLA_STATS_TX_INFO, 0}, 1948 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments}, 1949 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented}, 1950 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles}, 1951 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled}, 1952 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ? 1953 s->msg_length_counts : 1}, 1954 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts}, 1955 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total}, 1956 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]}, 1957 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]}, 1958 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]}, 1959 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]}, 1960 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]}, 1961 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]}, 1962 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]}, 1963 {TIPC_NLA_STATS_RX_STATES, s->recv_states}, 1964 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes}, 1965 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks}, 1966 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv}, 1967 {TIPC_NLA_STATS_TX_STATES, s->sent_states}, 1968 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes}, 1969 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks}, 1970 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks}, 1971 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted}, 1972 {TIPC_NLA_STATS_DUPLICATES, s->duplicates}, 1973 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs}, 1974 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz}, 1975 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ? 1976 (s->accu_queue_sz / s->queue_sz_counts) : 0} 1977 }; 1978 1979 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS); 1980 if (!stats) 1981 return -EMSGSIZE; 1982 1983 for (i = 0; i < ARRAY_SIZE(map); i++) 1984 if (nla_put_u32(skb, map[i].key, map[i].val)) 1985 goto msg_full; 1986 1987 nla_nest_end(skb, stats); 1988 1989 return 0; 1990 msg_full: 1991 nla_nest_cancel(skb, stats); 1992 1993 return -EMSGSIZE; 1994 } 1995 1996 /* Caller should hold appropriate locks to protect the link */ 1997 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg, 1998 struct tipc_link *link, int nlflags) 1999 { 2000 u32 self = tipc_own_addr(net); 2001 struct nlattr *attrs; 2002 struct nlattr *prop; 2003 void *hdr; 2004 int err; 2005 2006 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 2007 nlflags, TIPC_NL_LINK_GET); 2008 if (!hdr) 2009 return -EMSGSIZE; 2010 2011 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK); 2012 if (!attrs) 2013 goto msg_full; 2014 2015 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name)) 2016 goto attr_msg_full; 2017 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self))) 2018 goto attr_msg_full; 2019 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu)) 2020 goto attr_msg_full; 2021 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts)) 2022 goto attr_msg_full; 2023 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts)) 2024 goto attr_msg_full; 2025 2026 if (tipc_link_is_up(link)) 2027 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 2028 goto attr_msg_full; 2029 if (link->active) 2030 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE)) 2031 goto attr_msg_full; 2032 2033 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP); 2034 if (!prop) 2035 goto attr_msg_full; 2036 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 2037 goto prop_msg_full; 2038 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance)) 2039 goto prop_msg_full; 2040 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, 2041 link->window)) 2042 goto prop_msg_full; 2043 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 2044 goto prop_msg_full; 2045 nla_nest_end(msg->skb, prop); 2046 2047 err = __tipc_nl_add_stats(msg->skb, &link->stats); 2048 if (err) 2049 goto attr_msg_full; 2050 2051 nla_nest_end(msg->skb, attrs); 2052 genlmsg_end(msg->skb, hdr); 2053 2054 return 0; 2055 2056 prop_msg_full: 2057 nla_nest_cancel(msg->skb, prop); 2058 attr_msg_full: 2059 nla_nest_cancel(msg->skb, attrs); 2060 msg_full: 2061 genlmsg_cancel(msg->skb, hdr); 2062 2063 return -EMSGSIZE; 2064 } 2065 2066 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb, 2067 struct tipc_stats *stats) 2068 { 2069 int i; 2070 struct nlattr *nest; 2071 2072 struct nla_map { 2073 __u32 key; 2074 __u32 val; 2075 }; 2076 2077 struct nla_map map[] = { 2078 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts}, 2079 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments}, 2080 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented}, 2081 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles}, 2082 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled}, 2083 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts}, 2084 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments}, 2085 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented}, 2086 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles}, 2087 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled}, 2088 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks}, 2089 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv}, 2090 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks}, 2091 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks}, 2092 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted}, 2093 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates}, 2094 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs}, 2095 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz}, 2096 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ? 2097 (stats->accu_queue_sz / stats->queue_sz_counts) : 0} 2098 }; 2099 2100 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS); 2101 if (!nest) 2102 return -EMSGSIZE; 2103 2104 for (i = 0; i < ARRAY_SIZE(map); i++) 2105 if (nla_put_u32(skb, map[i].key, map[i].val)) 2106 goto msg_full; 2107 2108 nla_nest_end(skb, nest); 2109 2110 return 0; 2111 msg_full: 2112 nla_nest_cancel(skb, nest); 2113 2114 return -EMSGSIZE; 2115 } 2116 2117 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg) 2118 { 2119 int err; 2120 void *hdr; 2121 struct nlattr *attrs; 2122 struct nlattr *prop; 2123 struct tipc_net *tn = net_generic(net, tipc_net_id); 2124 struct tipc_link *bcl = tn->bcl; 2125 2126 if (!bcl) 2127 return 0; 2128 2129 tipc_bcast_lock(net); 2130 2131 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 2132 NLM_F_MULTI, TIPC_NL_LINK_GET); 2133 if (!hdr) { 2134 tipc_bcast_unlock(net); 2135 return -EMSGSIZE; 2136 } 2137 2138 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK); 2139 if (!attrs) 2140 goto msg_full; 2141 2142 /* The broadcast link is always up */ 2143 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 2144 goto attr_msg_full; 2145 2146 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST)) 2147 goto attr_msg_full; 2148 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name)) 2149 goto attr_msg_full; 2150 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0)) 2151 goto attr_msg_full; 2152 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0)) 2153 goto attr_msg_full; 2154 2155 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP); 2156 if (!prop) 2157 goto attr_msg_full; 2158 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window)) 2159 goto prop_msg_full; 2160 nla_nest_end(msg->skb, prop); 2161 2162 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats); 2163 if (err) 2164 goto attr_msg_full; 2165 2166 tipc_bcast_unlock(net); 2167 nla_nest_end(msg->skb, attrs); 2168 genlmsg_end(msg->skb, hdr); 2169 2170 return 0; 2171 2172 prop_msg_full: 2173 nla_nest_cancel(msg->skb, prop); 2174 attr_msg_full: 2175 nla_nest_cancel(msg->skb, attrs); 2176 msg_full: 2177 tipc_bcast_unlock(net); 2178 genlmsg_cancel(msg->skb, hdr); 2179 2180 return -EMSGSIZE; 2181 } 2182 2183 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol, 2184 struct sk_buff_head *xmitq) 2185 { 2186 l->tolerance = tol; 2187 if (link_is_up(l)) 2188 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq); 2189 } 2190 2191 void tipc_link_set_prio(struct tipc_link *l, u32 prio, 2192 struct sk_buff_head *xmitq) 2193 { 2194 l->priority = prio; 2195 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq); 2196 } 2197 2198 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit) 2199 { 2200 l->abort_limit = limit; 2201 } 2202