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