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 #include "trace.h" 47 48 #include <linux/pkt_sched.h> 49 50 struct tipc_stats { 51 u32 sent_pkts; 52 u32 recv_pkts; 53 u32 sent_states; 54 u32 recv_states; 55 u32 sent_probes; 56 u32 recv_probes; 57 u32 sent_nacks; 58 u32 recv_nacks; 59 u32 sent_acks; 60 u32 sent_bundled; 61 u32 sent_bundles; 62 u32 recv_bundled; 63 u32 recv_bundles; 64 u32 retransmitted; 65 u32 sent_fragmented; 66 u32 sent_fragments; 67 u32 recv_fragmented; 68 u32 recv_fragments; 69 u32 link_congs; /* # port sends blocked by congestion */ 70 u32 deferred_recv; 71 u32 duplicates; 72 u32 max_queue_sz; /* send queue size high water mark */ 73 u32 accu_queue_sz; /* used for send queue size profiling */ 74 u32 queue_sz_counts; /* used for send queue size profiling */ 75 u32 msg_length_counts; /* used for message length profiling */ 76 u32 msg_lengths_total; /* used for message length profiling */ 77 u32 msg_length_profile[7]; /* used for msg. length profiling */ 78 }; 79 80 /** 81 * struct tipc_link - TIPC link data structure 82 * @addr: network address of link's peer node 83 * @name: link name character string 84 * @media_addr: media address to use when sending messages over link 85 * @timer: link timer 86 * @net: pointer to namespace struct 87 * @refcnt: reference counter for permanent references (owner node & timer) 88 * @peer_session: link session # being used by peer end of link 89 * @peer_bearer_id: bearer id used by link's peer endpoint 90 * @bearer_id: local bearer id used by link 91 * @tolerance: minimum link continuity loss needed to reset link [in ms] 92 * @abort_limit: # of unacknowledged continuity probes needed to reset link 93 * @state: current state of link FSM 94 * @peer_caps: bitmap describing capabilities of peer node 95 * @silent_intv_cnt: # of timer intervals without any reception from peer 96 * @proto_msg: template for control messages generated by link 97 * @pmsg: convenience pointer to "proto_msg" field 98 * @priority: current link priority 99 * @net_plane: current link network plane ('A' through 'H') 100 * @mon_state: cookie with information needed by link monitor 101 * @backlog_limit: backlog queue congestion thresholds (indexed by importance) 102 * @exp_msg_count: # of tunnelled messages expected during link changeover 103 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset 104 * @mtu: current maximum packet size for this link 105 * @advertised_mtu: advertised own mtu when link is being established 106 * @transmitq: queue for sent, non-acked messages 107 * @backlogq: queue for messages waiting to be sent 108 * @snt_nxt: next sequence number to use for outbound messages 109 * @prev_from: sequence number of most previous retransmission request 110 * @stale_cnt: counter for number of identical retransmit attempts 111 * @stale_limit: time when repeated identical retransmits must force link reset 112 * @ackers: # of peers that needs to ack each packet before it can be released 113 * @acked: # last packet acked by a certain peer. Used for broadcast. 114 * @rcv_nxt: next sequence number to expect for inbound messages 115 * @deferred_queue: deferred queue saved OOS b'cast message received from node 116 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 117 * @inputq: buffer queue for messages to be delivered upwards 118 * @namedq: buffer queue for name table messages to be delivered upwards 119 * @next_out: ptr to first unsent outbound message in queue 120 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate 121 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 122 * @reasm_buf: head of partially reassembled inbound message fragments 123 * @bc_rcvr: marks that this is a broadcast receiver link 124 * @stats: collects statistics regarding link activity 125 */ 126 struct tipc_link { 127 u32 addr; 128 char name[TIPC_MAX_LINK_NAME]; 129 struct net *net; 130 131 /* Management and link supervision data */ 132 u16 peer_session; 133 u16 session; 134 u16 snd_nxt_state; 135 u16 rcv_nxt_state; 136 u32 peer_bearer_id; 137 u32 bearer_id; 138 u32 tolerance; 139 u32 abort_limit; 140 u32 state; 141 u16 peer_caps; 142 bool in_session; 143 bool active; 144 u32 silent_intv_cnt; 145 char if_name[TIPC_MAX_IF_NAME]; 146 u32 priority; 147 char net_plane; 148 struct tipc_mon_state mon_state; 149 u16 rst_cnt; 150 151 /* Failover/synch */ 152 u16 drop_point; 153 struct sk_buff *failover_reasm_skb; 154 struct sk_buff_head failover_deferdq; 155 156 /* Max packet negotiation */ 157 u16 mtu; 158 u16 advertised_mtu; 159 160 /* Sending */ 161 struct sk_buff_head transmq; 162 struct sk_buff_head backlogq; 163 struct { 164 u16 len; 165 u16 limit; 166 } backlog[5]; 167 u16 snd_nxt; 168 u16 prev_from; 169 u16 window; 170 u16 stale_cnt; 171 unsigned long stale_limit; 172 173 /* Reception */ 174 u16 rcv_nxt; 175 u32 rcv_unacked; 176 struct sk_buff_head deferdq; 177 struct sk_buff_head *inputq; 178 struct sk_buff_head *namedq; 179 180 /* Congestion handling */ 181 struct sk_buff_head wakeupq; 182 183 /* Fragmentation/reassembly */ 184 struct sk_buff *reasm_buf; 185 186 /* Broadcast */ 187 u16 ackers; 188 u16 acked; 189 struct tipc_link *bc_rcvlink; 190 struct tipc_link *bc_sndlink; 191 u8 nack_state; 192 bool bc_peer_is_up; 193 194 /* Statistics */ 195 struct tipc_stats stats; 196 }; 197 198 /* 199 * Error message prefixes 200 */ 201 static const char *link_co_err = "Link tunneling error, "; 202 static const char *link_rst_msg = "Resetting link "; 203 204 /* Send states for broadcast NACKs 205 */ 206 enum { 207 BC_NACK_SND_CONDITIONAL, 208 BC_NACK_SND_UNCONDITIONAL, 209 BC_NACK_SND_SUPPRESS, 210 }; 211 212 #define TIPC_BC_RETR_LIM msecs_to_jiffies(10) /* [ms] */ 213 #define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1)) 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 static u16 tipc_build_gap_ack_blks(struct tipc_link *l, void *data); 252 static int tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap, 253 struct tipc_gap_ack_blks *ga, 254 struct sk_buff_head *xmitq); 255 256 /* 257 * Simple non-static link routines (i.e. referenced outside this file) 258 */ 259 bool tipc_link_is_up(struct tipc_link *l) 260 { 261 return link_is_up(l); 262 } 263 264 bool tipc_link_peer_is_down(struct tipc_link *l) 265 { 266 return l->state == LINK_PEER_RESET; 267 } 268 269 bool tipc_link_is_reset(struct tipc_link *l) 270 { 271 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING); 272 } 273 274 bool tipc_link_is_establishing(struct tipc_link *l) 275 { 276 return l->state == LINK_ESTABLISHING; 277 } 278 279 bool tipc_link_is_synching(struct tipc_link *l) 280 { 281 return l->state == LINK_SYNCHING; 282 } 283 284 bool tipc_link_is_failingover(struct tipc_link *l) 285 { 286 return l->state == LINK_FAILINGOVER; 287 } 288 289 bool tipc_link_is_blocked(struct tipc_link *l) 290 { 291 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER); 292 } 293 294 static bool link_is_bc_sndlink(struct tipc_link *l) 295 { 296 return !l->bc_sndlink; 297 } 298 299 static bool link_is_bc_rcvlink(struct tipc_link *l) 300 { 301 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l)); 302 } 303 304 void tipc_link_set_active(struct tipc_link *l, bool active) 305 { 306 l->active = active; 307 } 308 309 u32 tipc_link_id(struct tipc_link *l) 310 { 311 return l->peer_bearer_id << 16 | l->bearer_id; 312 } 313 314 int tipc_link_window(struct tipc_link *l) 315 { 316 return l->window; 317 } 318 319 int tipc_link_prio(struct tipc_link *l) 320 { 321 return l->priority; 322 } 323 324 unsigned long tipc_link_tolerance(struct tipc_link *l) 325 { 326 return l->tolerance; 327 } 328 329 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l) 330 { 331 return l->inputq; 332 } 333 334 char tipc_link_plane(struct tipc_link *l) 335 { 336 return l->net_plane; 337 } 338 339 void tipc_link_update_caps(struct tipc_link *l, u16 capabilities) 340 { 341 l->peer_caps = capabilities; 342 } 343 344 void tipc_link_add_bc_peer(struct tipc_link *snd_l, 345 struct tipc_link *uc_l, 346 struct sk_buff_head *xmitq) 347 { 348 struct tipc_link *rcv_l = uc_l->bc_rcvlink; 349 350 snd_l->ackers++; 351 rcv_l->acked = snd_l->snd_nxt - 1; 352 snd_l->state = LINK_ESTABLISHED; 353 tipc_link_build_bc_init_msg(uc_l, xmitq); 354 } 355 356 void tipc_link_remove_bc_peer(struct tipc_link *snd_l, 357 struct tipc_link *rcv_l, 358 struct sk_buff_head *xmitq) 359 { 360 u16 ack = snd_l->snd_nxt - 1; 361 362 snd_l->ackers--; 363 rcv_l->bc_peer_is_up = true; 364 rcv_l->state = LINK_ESTABLISHED; 365 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq); 366 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!"); 367 tipc_link_reset(rcv_l); 368 rcv_l->state = LINK_RESET; 369 if (!snd_l->ackers) { 370 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!"); 371 tipc_link_reset(snd_l); 372 snd_l->state = LINK_RESET; 373 __skb_queue_purge(xmitq); 374 } 375 } 376 377 int tipc_link_bc_peers(struct tipc_link *l) 378 { 379 return l->ackers; 380 } 381 382 static u16 link_bc_rcv_gap(struct tipc_link *l) 383 { 384 struct sk_buff *skb = skb_peek(&l->deferdq); 385 u16 gap = 0; 386 387 if (more(l->snd_nxt, l->rcv_nxt)) 388 gap = l->snd_nxt - l->rcv_nxt; 389 if (skb) 390 gap = buf_seqno(skb) - l->rcv_nxt; 391 return gap; 392 } 393 394 void tipc_link_set_mtu(struct tipc_link *l, int mtu) 395 { 396 l->mtu = mtu; 397 } 398 399 int tipc_link_mtu(struct tipc_link *l) 400 { 401 return l->mtu; 402 } 403 404 u16 tipc_link_rcv_nxt(struct tipc_link *l) 405 { 406 return l->rcv_nxt; 407 } 408 409 u16 tipc_link_acked(struct tipc_link *l) 410 { 411 return l->acked; 412 } 413 414 char *tipc_link_name(struct tipc_link *l) 415 { 416 return l->name; 417 } 418 419 u32 tipc_link_state(struct tipc_link *l) 420 { 421 return l->state; 422 } 423 424 /** 425 * tipc_link_create - create a new link 426 * @n: pointer to associated node 427 * @if_name: associated interface name 428 * @bearer_id: id (index) of associated bearer 429 * @tolerance: link tolerance to be used by link 430 * @net_plane: network plane (A,B,c..) this link belongs to 431 * @mtu: mtu to be advertised by link 432 * @priority: priority to be used by link 433 * @window: send window to be used by link 434 * @session: session to be used by link 435 * @ownnode: identity of own node 436 * @peer: node id of peer node 437 * @peer_caps: bitmap describing peer node capabilities 438 * @bc_sndlink: the namespace global link used for broadcast sending 439 * @bc_rcvlink: the peer specific link used for broadcast reception 440 * @inputq: queue to put messages ready for delivery 441 * @namedq: queue to put binding table update messages ready for delivery 442 * @link: return value, pointer to put the created link 443 * 444 * Returns true if link was created, otherwise false 445 */ 446 bool tipc_link_create(struct net *net, char *if_name, int bearer_id, 447 int tolerance, char net_plane, u32 mtu, int priority, 448 int window, u32 session, u32 self, 449 u32 peer, u8 *peer_id, u16 peer_caps, 450 struct tipc_link *bc_sndlink, 451 struct tipc_link *bc_rcvlink, 452 struct sk_buff_head *inputq, 453 struct sk_buff_head *namedq, 454 struct tipc_link **link) 455 { 456 char peer_str[NODE_ID_STR_LEN] = {0,}; 457 char self_str[NODE_ID_STR_LEN] = {0,}; 458 struct tipc_link *l; 459 460 l = kzalloc(sizeof(*l), GFP_ATOMIC); 461 if (!l) 462 return false; 463 *link = l; 464 l->session = session; 465 466 /* Set link name for unicast links only */ 467 if (peer_id) { 468 tipc_nodeid2string(self_str, tipc_own_id(net)); 469 if (strlen(self_str) > 16) 470 sprintf(self_str, "%x", self); 471 tipc_nodeid2string(peer_str, peer_id); 472 if (strlen(peer_str) > 16) 473 sprintf(peer_str, "%x", peer); 474 } 475 /* Peer i/f name will be completed by reset/activate message */ 476 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown", 477 self_str, if_name, peer_str); 478 479 strcpy(l->if_name, if_name); 480 l->addr = peer; 481 l->peer_caps = peer_caps; 482 l->net = net; 483 l->in_session = false; 484 l->bearer_id = bearer_id; 485 l->tolerance = tolerance; 486 if (bc_rcvlink) 487 bc_rcvlink->tolerance = tolerance; 488 l->net_plane = net_plane; 489 l->advertised_mtu = mtu; 490 l->mtu = mtu; 491 l->priority = priority; 492 tipc_link_set_queue_limits(l, window); 493 l->ackers = 1; 494 l->bc_sndlink = bc_sndlink; 495 l->bc_rcvlink = bc_rcvlink; 496 l->inputq = inputq; 497 l->namedq = namedq; 498 l->state = LINK_RESETTING; 499 __skb_queue_head_init(&l->transmq); 500 __skb_queue_head_init(&l->backlogq); 501 __skb_queue_head_init(&l->deferdq); 502 __skb_queue_head_init(&l->failover_deferdq); 503 skb_queue_head_init(&l->wakeupq); 504 skb_queue_head_init(l->inputq); 505 return true; 506 } 507 508 /** 509 * tipc_link_bc_create - create new link to be used for broadcast 510 * @n: pointer to associated node 511 * @mtu: mtu to be used initially if no peers 512 * @window: send window to be used 513 * @inputq: queue to put messages ready for delivery 514 * @namedq: queue to put binding table update messages ready for delivery 515 * @link: return value, pointer to put the created link 516 * 517 * Returns true if link was created, otherwise false 518 */ 519 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, 520 int mtu, int window, u16 peer_caps, 521 struct sk_buff_head *inputq, 522 struct sk_buff_head *namedq, 523 struct tipc_link *bc_sndlink, 524 struct tipc_link **link) 525 { 526 struct tipc_link *l; 527 528 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window, 529 0, ownnode, peer, NULL, peer_caps, bc_sndlink, 530 NULL, inputq, namedq, link)) 531 return false; 532 533 l = *link; 534 strcpy(l->name, tipc_bclink_name); 535 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!"); 536 tipc_link_reset(l); 537 l->state = LINK_RESET; 538 l->ackers = 0; 539 l->bc_rcvlink = l; 540 541 /* Broadcast send link is always up */ 542 if (link_is_bc_sndlink(l)) 543 l->state = LINK_ESTABLISHED; 544 545 /* Disable replicast if even a single peer doesn't support it */ 546 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST)) 547 tipc_bcast_disable_rcast(net); 548 549 return true; 550 } 551 552 /** 553 * tipc_link_fsm_evt - link finite state machine 554 * @l: pointer to link 555 * @evt: state machine event to be processed 556 */ 557 int tipc_link_fsm_evt(struct tipc_link *l, int evt) 558 { 559 int rc = 0; 560 int old_state = l->state; 561 562 switch (l->state) { 563 case LINK_RESETTING: 564 switch (evt) { 565 case LINK_PEER_RESET_EVT: 566 l->state = LINK_PEER_RESET; 567 break; 568 case LINK_RESET_EVT: 569 l->state = LINK_RESET; 570 break; 571 case LINK_FAILURE_EVT: 572 case LINK_FAILOVER_BEGIN_EVT: 573 case LINK_ESTABLISH_EVT: 574 case LINK_FAILOVER_END_EVT: 575 case LINK_SYNCH_BEGIN_EVT: 576 case LINK_SYNCH_END_EVT: 577 default: 578 goto illegal_evt; 579 } 580 break; 581 case LINK_RESET: 582 switch (evt) { 583 case LINK_PEER_RESET_EVT: 584 l->state = LINK_ESTABLISHING; 585 break; 586 case LINK_FAILOVER_BEGIN_EVT: 587 l->state = LINK_FAILINGOVER; 588 case LINK_FAILURE_EVT: 589 case LINK_RESET_EVT: 590 case LINK_ESTABLISH_EVT: 591 case LINK_FAILOVER_END_EVT: 592 break; 593 case LINK_SYNCH_BEGIN_EVT: 594 case LINK_SYNCH_END_EVT: 595 default: 596 goto illegal_evt; 597 } 598 break; 599 case LINK_PEER_RESET: 600 switch (evt) { 601 case LINK_RESET_EVT: 602 l->state = LINK_ESTABLISHING; 603 break; 604 case LINK_PEER_RESET_EVT: 605 case LINK_ESTABLISH_EVT: 606 case LINK_FAILURE_EVT: 607 break; 608 case LINK_SYNCH_BEGIN_EVT: 609 case LINK_SYNCH_END_EVT: 610 case LINK_FAILOVER_BEGIN_EVT: 611 case LINK_FAILOVER_END_EVT: 612 default: 613 goto illegal_evt; 614 } 615 break; 616 case LINK_FAILINGOVER: 617 switch (evt) { 618 case LINK_FAILOVER_END_EVT: 619 l->state = LINK_RESET; 620 break; 621 case LINK_PEER_RESET_EVT: 622 case LINK_RESET_EVT: 623 case LINK_ESTABLISH_EVT: 624 case LINK_FAILURE_EVT: 625 break; 626 case LINK_FAILOVER_BEGIN_EVT: 627 case LINK_SYNCH_BEGIN_EVT: 628 case LINK_SYNCH_END_EVT: 629 default: 630 goto illegal_evt; 631 } 632 break; 633 case LINK_ESTABLISHING: 634 switch (evt) { 635 case LINK_ESTABLISH_EVT: 636 l->state = LINK_ESTABLISHED; 637 break; 638 case LINK_FAILOVER_BEGIN_EVT: 639 l->state = LINK_FAILINGOVER; 640 break; 641 case LINK_RESET_EVT: 642 l->state = LINK_RESET; 643 break; 644 case LINK_FAILURE_EVT: 645 case LINK_PEER_RESET_EVT: 646 case LINK_SYNCH_BEGIN_EVT: 647 case LINK_FAILOVER_END_EVT: 648 break; 649 case LINK_SYNCH_END_EVT: 650 default: 651 goto illegal_evt; 652 } 653 break; 654 case LINK_ESTABLISHED: 655 switch (evt) { 656 case LINK_PEER_RESET_EVT: 657 l->state = LINK_PEER_RESET; 658 rc |= TIPC_LINK_DOWN_EVT; 659 break; 660 case LINK_FAILURE_EVT: 661 l->state = LINK_RESETTING; 662 rc |= TIPC_LINK_DOWN_EVT; 663 break; 664 case LINK_RESET_EVT: 665 l->state = LINK_RESET; 666 break; 667 case LINK_ESTABLISH_EVT: 668 case LINK_SYNCH_END_EVT: 669 break; 670 case LINK_SYNCH_BEGIN_EVT: 671 l->state = LINK_SYNCHING; 672 break; 673 case LINK_FAILOVER_BEGIN_EVT: 674 case LINK_FAILOVER_END_EVT: 675 default: 676 goto illegal_evt; 677 } 678 break; 679 case LINK_SYNCHING: 680 switch (evt) { 681 case LINK_PEER_RESET_EVT: 682 l->state = LINK_PEER_RESET; 683 rc |= TIPC_LINK_DOWN_EVT; 684 break; 685 case LINK_FAILURE_EVT: 686 l->state = LINK_RESETTING; 687 rc |= TIPC_LINK_DOWN_EVT; 688 break; 689 case LINK_RESET_EVT: 690 l->state = LINK_RESET; 691 break; 692 case LINK_ESTABLISH_EVT: 693 case LINK_SYNCH_BEGIN_EVT: 694 break; 695 case LINK_SYNCH_END_EVT: 696 l->state = LINK_ESTABLISHED; 697 break; 698 case LINK_FAILOVER_BEGIN_EVT: 699 case LINK_FAILOVER_END_EVT: 700 default: 701 goto illegal_evt; 702 } 703 break; 704 default: 705 pr_err("Unknown FSM state %x in %s\n", l->state, l->name); 706 } 707 trace_tipc_link_fsm(l->name, old_state, l->state, evt); 708 return rc; 709 illegal_evt: 710 pr_err("Illegal FSM event %x in state %x on link %s\n", 711 evt, l->state, l->name); 712 trace_tipc_link_fsm(l->name, old_state, l->state, evt); 713 return rc; 714 } 715 716 /* link_profile_stats - update statistical profiling of traffic 717 */ 718 static void link_profile_stats(struct tipc_link *l) 719 { 720 struct sk_buff *skb; 721 struct tipc_msg *msg; 722 int length; 723 724 /* Update counters used in statistical profiling of send traffic */ 725 l->stats.accu_queue_sz += skb_queue_len(&l->transmq); 726 l->stats.queue_sz_counts++; 727 728 skb = skb_peek(&l->transmq); 729 if (!skb) 730 return; 731 msg = buf_msg(skb); 732 length = msg_size(msg); 733 734 if (msg_user(msg) == MSG_FRAGMENTER) { 735 if (msg_type(msg) != FIRST_FRAGMENT) 736 return; 737 length = msg_size(msg_get_wrapped(msg)); 738 } 739 l->stats.msg_lengths_total += length; 740 l->stats.msg_length_counts++; 741 if (length <= 64) 742 l->stats.msg_length_profile[0]++; 743 else if (length <= 256) 744 l->stats.msg_length_profile[1]++; 745 else if (length <= 1024) 746 l->stats.msg_length_profile[2]++; 747 else if (length <= 4096) 748 l->stats.msg_length_profile[3]++; 749 else if (length <= 16384) 750 l->stats.msg_length_profile[4]++; 751 else if (length <= 32768) 752 l->stats.msg_length_profile[5]++; 753 else 754 l->stats.msg_length_profile[6]++; 755 } 756 757 /** 758 * tipc_link_too_silent - check if link is "too silent" 759 * @l: tipc link to be checked 760 * 761 * Returns true if the link 'silent_intv_cnt' is about to reach the 762 * 'abort_limit' value, otherwise false 763 */ 764 bool tipc_link_too_silent(struct tipc_link *l) 765 { 766 return (l->silent_intv_cnt + 2 > l->abort_limit); 767 } 768 769 /* tipc_link_timeout - perform periodic task as instructed from node timeout 770 */ 771 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq) 772 { 773 int mtyp = 0; 774 int rc = 0; 775 bool state = false; 776 bool probe = false; 777 bool setup = false; 778 u16 bc_snt = l->bc_sndlink->snd_nxt - 1; 779 u16 bc_acked = l->bc_rcvlink->acked; 780 struct tipc_mon_state *mstate = &l->mon_state; 781 782 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " "); 783 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " "); 784 switch (l->state) { 785 case LINK_ESTABLISHED: 786 case LINK_SYNCHING: 787 mtyp = STATE_MSG; 788 link_profile_stats(l); 789 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id); 790 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit)) 791 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 792 state = bc_acked != bc_snt; 793 state |= l->bc_rcvlink->rcv_unacked; 794 state |= l->rcv_unacked; 795 state |= !skb_queue_empty(&l->transmq); 796 state |= !skb_queue_empty(&l->deferdq); 797 probe = mstate->probing; 798 probe |= l->silent_intv_cnt; 799 if (probe || mstate->monitoring) 800 l->silent_intv_cnt++; 801 break; 802 case LINK_RESET: 803 setup = l->rst_cnt++ <= 4; 804 setup |= !(l->rst_cnt % 16); 805 mtyp = RESET_MSG; 806 break; 807 case LINK_ESTABLISHING: 808 setup = true; 809 mtyp = ACTIVATE_MSG; 810 break; 811 case LINK_PEER_RESET: 812 case LINK_RESETTING: 813 case LINK_FAILINGOVER: 814 break; 815 default: 816 break; 817 } 818 819 if (state || probe || setup) 820 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq); 821 822 return rc; 823 } 824 825 /** 826 * link_schedule_user - schedule a message sender for wakeup after congestion 827 * @l: congested link 828 * @hdr: header of message that is being sent 829 * Create pseudo msg to send back to user when congestion abates 830 */ 831 static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr) 832 { 833 u32 dnode = tipc_own_addr(l->net); 834 u32 dport = msg_origport(hdr); 835 struct sk_buff *skb; 836 837 /* Create and schedule wakeup pseudo message */ 838 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0, 839 dnode, l->addr, dport, 0, 0); 840 if (!skb) 841 return -ENOBUFS; 842 msg_set_dest_droppable(buf_msg(skb), true); 843 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr); 844 skb_queue_tail(&l->wakeupq, skb); 845 l->stats.link_congs++; 846 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!"); 847 return -ELINKCONG; 848 } 849 850 /** 851 * link_prepare_wakeup - prepare users for wakeup after congestion 852 * @l: congested link 853 * Wake up a number of waiting users, as permitted by available space 854 * in the send queue 855 */ 856 static void link_prepare_wakeup(struct tipc_link *l) 857 { 858 struct sk_buff *skb, *tmp; 859 int imp, i = 0; 860 861 skb_queue_walk_safe(&l->wakeupq, skb, tmp) { 862 imp = TIPC_SKB_CB(skb)->chain_imp; 863 if (l->backlog[imp].len < l->backlog[imp].limit) { 864 skb_unlink(skb, &l->wakeupq); 865 skb_queue_tail(l->inputq, skb); 866 } else if (i++ > 10) { 867 break; 868 } 869 } 870 } 871 872 void tipc_link_reset(struct tipc_link *l) 873 { 874 struct sk_buff_head list; 875 876 __skb_queue_head_init(&list); 877 878 l->in_session = false; 879 /* Force re-synch of peer session number before establishing */ 880 l->peer_session--; 881 l->session++; 882 l->mtu = l->advertised_mtu; 883 884 spin_lock_bh(&l->wakeupq.lock); 885 skb_queue_splice_init(&l->wakeupq, &list); 886 spin_unlock_bh(&l->wakeupq.lock); 887 888 spin_lock_bh(&l->inputq->lock); 889 skb_queue_splice_init(&list, l->inputq); 890 spin_unlock_bh(&l->inputq->lock); 891 892 __skb_queue_purge(&l->transmq); 893 __skb_queue_purge(&l->deferdq); 894 __skb_queue_purge(&l->backlogq); 895 __skb_queue_purge(&l->failover_deferdq); 896 l->backlog[TIPC_LOW_IMPORTANCE].len = 0; 897 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0; 898 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0; 899 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0; 900 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0; 901 kfree_skb(l->reasm_buf); 902 kfree_skb(l->failover_reasm_skb); 903 l->reasm_buf = NULL; 904 l->failover_reasm_skb = NULL; 905 l->rcv_unacked = 0; 906 l->snd_nxt = 1; 907 l->rcv_nxt = 1; 908 l->snd_nxt_state = 1; 909 l->rcv_nxt_state = 1; 910 l->acked = 0; 911 l->silent_intv_cnt = 0; 912 l->rst_cnt = 0; 913 l->stale_cnt = 0; 914 l->bc_peer_is_up = false; 915 memset(&l->mon_state, 0, sizeof(l->mon_state)); 916 tipc_link_reset_stats(l); 917 } 918 919 /** 920 * tipc_link_xmit(): enqueue buffer list according to queue situation 921 * @link: link to use 922 * @list: chain of buffers containing message 923 * @xmitq: returned list of packets to be sent by caller 924 * 925 * Consumes the buffer chain. 926 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS 927 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted 928 */ 929 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list, 930 struct sk_buff_head *xmitq) 931 { 932 struct tipc_msg *hdr = buf_msg(skb_peek(list)); 933 unsigned int maxwin = l->window; 934 int imp = msg_importance(hdr); 935 unsigned int mtu = l->mtu; 936 u16 ack = l->rcv_nxt - 1; 937 u16 seqno = l->snd_nxt; 938 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 939 struct sk_buff_head *transmq = &l->transmq; 940 struct sk_buff_head *backlogq = &l->backlogq; 941 struct sk_buff *skb, *_skb, *bskb; 942 int pkt_cnt = skb_queue_len(list); 943 int rc = 0; 944 945 if (unlikely(msg_size(hdr) > mtu)) { 946 skb_queue_purge(list); 947 return -EMSGSIZE; 948 } 949 950 /* Allow oversubscription of one data msg per source at congestion */ 951 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) { 952 if (imp == TIPC_SYSTEM_IMPORTANCE) { 953 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name); 954 return -ENOBUFS; 955 } 956 rc = link_schedule_user(l, hdr); 957 } 958 959 if (pkt_cnt > 1) { 960 l->stats.sent_fragmented++; 961 l->stats.sent_fragments += pkt_cnt; 962 } 963 964 /* Prepare each packet for sending, and add to relevant queue: */ 965 while (skb_queue_len(list)) { 966 skb = skb_peek(list); 967 hdr = buf_msg(skb); 968 msg_set_seqno(hdr, seqno); 969 msg_set_ack(hdr, ack); 970 msg_set_bcast_ack(hdr, bc_ack); 971 972 if (likely(skb_queue_len(transmq) < maxwin)) { 973 _skb = skb_clone(skb, GFP_ATOMIC); 974 if (!_skb) { 975 skb_queue_purge(list); 976 return -ENOBUFS; 977 } 978 __skb_dequeue(list); 979 __skb_queue_tail(transmq, skb); 980 /* next retransmit attempt */ 981 if (link_is_bc_sndlink(l)) 982 TIPC_SKB_CB(skb)->nxt_retr = 983 jiffies + TIPC_BC_RETR_LIM; 984 __skb_queue_tail(xmitq, _skb); 985 TIPC_SKB_CB(skb)->ackers = l->ackers; 986 l->rcv_unacked = 0; 987 l->stats.sent_pkts++; 988 seqno++; 989 continue; 990 } 991 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) { 992 kfree_skb(__skb_dequeue(list)); 993 l->stats.sent_bundled++; 994 continue; 995 } 996 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) { 997 kfree_skb(__skb_dequeue(list)); 998 __skb_queue_tail(backlogq, bskb); 999 l->backlog[msg_importance(buf_msg(bskb))].len++; 1000 l->stats.sent_bundled++; 1001 l->stats.sent_bundles++; 1002 continue; 1003 } 1004 l->backlog[imp].len += skb_queue_len(list); 1005 skb_queue_splice_tail_init(list, backlogq); 1006 } 1007 l->snd_nxt = seqno; 1008 return rc; 1009 } 1010 1011 static void tipc_link_advance_backlog(struct tipc_link *l, 1012 struct sk_buff_head *xmitq) 1013 { 1014 struct sk_buff *skb, *_skb; 1015 struct tipc_msg *hdr; 1016 u16 seqno = l->snd_nxt; 1017 u16 ack = l->rcv_nxt - 1; 1018 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 1019 1020 while (skb_queue_len(&l->transmq) < l->window) { 1021 skb = skb_peek(&l->backlogq); 1022 if (!skb) 1023 break; 1024 _skb = skb_clone(skb, GFP_ATOMIC); 1025 if (!_skb) 1026 break; 1027 __skb_dequeue(&l->backlogq); 1028 hdr = buf_msg(skb); 1029 l->backlog[msg_importance(hdr)].len--; 1030 __skb_queue_tail(&l->transmq, skb); 1031 /* next retransmit attempt */ 1032 if (link_is_bc_sndlink(l)) 1033 TIPC_SKB_CB(skb)->nxt_retr = jiffies + TIPC_BC_RETR_LIM; 1034 1035 __skb_queue_tail(xmitq, _skb); 1036 TIPC_SKB_CB(skb)->ackers = l->ackers; 1037 msg_set_seqno(hdr, seqno); 1038 msg_set_ack(hdr, ack); 1039 msg_set_bcast_ack(hdr, bc_ack); 1040 l->rcv_unacked = 0; 1041 l->stats.sent_pkts++; 1042 seqno++; 1043 } 1044 l->snd_nxt = seqno; 1045 } 1046 1047 /** 1048 * link_retransmit_failure() - Detect repeated retransmit failures 1049 * @l: tipc link sender 1050 * @r: tipc link receiver (= l in case of unicast) 1051 * @from: seqno of the 1st packet in retransmit request 1052 * @rc: returned code 1053 * 1054 * Return: true if the repeated retransmit failures happens, otherwise 1055 * false 1056 */ 1057 static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r, 1058 u16 from, int *rc) 1059 { 1060 struct sk_buff *skb = skb_peek(&l->transmq); 1061 struct tipc_msg *hdr; 1062 1063 if (!skb) 1064 return false; 1065 hdr = buf_msg(skb); 1066 1067 /* Detect repeated retransmit failures on same packet */ 1068 if (r->prev_from != from) { 1069 r->prev_from = from; 1070 r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance); 1071 r->stale_cnt = 0; 1072 } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) { 1073 pr_warn("Retransmission failure on link <%s>\n", l->name); 1074 link_print(l, "State of link "); 1075 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n", 1076 msg_user(hdr), msg_type(hdr), msg_size(hdr), 1077 msg_errcode(hdr)); 1078 pr_info("sqno %u, prev: %x, src: %x\n", 1079 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr)); 1080 1081 trace_tipc_list_dump(&l->transmq, true, "retrans failure!"); 1082 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!"); 1083 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!"); 1084 1085 if (link_is_bc_sndlink(l)) 1086 *rc = TIPC_LINK_DOWN_EVT; 1087 1088 *rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1089 return true; 1090 } 1091 1092 return false; 1093 } 1094 1095 /* tipc_link_bc_retrans() - retransmit zero or more packets 1096 * @l: the link to transmit on 1097 * @r: the receiving link ordering the retransmit. Same as l if unicast 1098 * @from: retransmit from (inclusive) this sequence number 1099 * @to: retransmit to (inclusive) this sequence number 1100 * xmitq: queue for accumulating the retransmitted packets 1101 */ 1102 static int tipc_link_bc_retrans(struct tipc_link *l, struct tipc_link *r, 1103 u16 from, u16 to, struct sk_buff_head *xmitq) 1104 { 1105 struct sk_buff *_skb, *skb = skb_peek(&l->transmq); 1106 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 1107 u16 ack = l->rcv_nxt - 1; 1108 struct tipc_msg *hdr; 1109 int rc = 0; 1110 1111 if (!skb) 1112 return 0; 1113 if (less(to, from)) 1114 return 0; 1115 1116 trace_tipc_link_retrans(r, from, to, &l->transmq); 1117 1118 if (link_retransmit_failure(l, r, from, &rc)) 1119 return rc; 1120 1121 skb_queue_walk(&l->transmq, skb) { 1122 hdr = buf_msg(skb); 1123 if (less(msg_seqno(hdr), from)) 1124 continue; 1125 if (more(msg_seqno(hdr), to)) 1126 break; 1127 if (link_is_bc_sndlink(l)) { 1128 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr)) 1129 continue; 1130 TIPC_SKB_CB(skb)->nxt_retr = jiffies + TIPC_BC_RETR_LIM; 1131 } 1132 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC); 1133 if (!_skb) 1134 return 0; 1135 hdr = buf_msg(_skb); 1136 msg_set_ack(hdr, ack); 1137 msg_set_bcast_ack(hdr, bc_ack); 1138 _skb->priority = TC_PRIO_CONTROL; 1139 __skb_queue_tail(xmitq, _skb); 1140 l->stats.retransmitted++; 1141 } 1142 return 0; 1143 } 1144 1145 /* tipc_data_input - deliver data and name distr msgs to upper layer 1146 * 1147 * Consumes buffer if message is of right type 1148 * Node lock must be held 1149 */ 1150 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb, 1151 struct sk_buff_head *inputq) 1152 { 1153 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq; 1154 struct tipc_msg *hdr = buf_msg(skb); 1155 1156 switch (msg_user(hdr)) { 1157 case TIPC_LOW_IMPORTANCE: 1158 case TIPC_MEDIUM_IMPORTANCE: 1159 case TIPC_HIGH_IMPORTANCE: 1160 case TIPC_CRITICAL_IMPORTANCE: 1161 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) { 1162 skb_queue_tail(mc_inputq, skb); 1163 return true; 1164 } 1165 /* fall through */ 1166 case CONN_MANAGER: 1167 skb_queue_tail(inputq, skb); 1168 return true; 1169 case GROUP_PROTOCOL: 1170 skb_queue_tail(mc_inputq, skb); 1171 return true; 1172 case NAME_DISTRIBUTOR: 1173 l->bc_rcvlink->state = LINK_ESTABLISHED; 1174 skb_queue_tail(l->namedq, skb); 1175 return true; 1176 case MSG_BUNDLER: 1177 case TUNNEL_PROTOCOL: 1178 case MSG_FRAGMENTER: 1179 case BCAST_PROTOCOL: 1180 return false; 1181 default: 1182 pr_warn("Dropping received illegal msg type\n"); 1183 kfree_skb(skb); 1184 return true; 1185 }; 1186 } 1187 1188 /* tipc_link_input - process packet that has passed link protocol check 1189 * 1190 * Consumes buffer 1191 */ 1192 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb, 1193 struct sk_buff_head *inputq, 1194 struct sk_buff **reasm_skb) 1195 { 1196 struct tipc_msg *hdr = buf_msg(skb); 1197 struct sk_buff *iskb; 1198 struct sk_buff_head tmpq; 1199 int usr = msg_user(hdr); 1200 int pos = 0; 1201 1202 if (usr == MSG_BUNDLER) { 1203 skb_queue_head_init(&tmpq); 1204 l->stats.recv_bundles++; 1205 l->stats.recv_bundled += msg_msgcnt(hdr); 1206 while (tipc_msg_extract(skb, &iskb, &pos)) 1207 tipc_data_input(l, iskb, &tmpq); 1208 tipc_skb_queue_splice_tail(&tmpq, inputq); 1209 return 0; 1210 } else if (usr == MSG_FRAGMENTER) { 1211 l->stats.recv_fragments++; 1212 if (tipc_buf_append(reasm_skb, &skb)) { 1213 l->stats.recv_fragmented++; 1214 tipc_data_input(l, skb, inputq); 1215 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) { 1216 pr_warn_ratelimited("Unable to build fragment list\n"); 1217 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1218 } 1219 return 0; 1220 } else if (usr == BCAST_PROTOCOL) { 1221 tipc_bcast_lock(l->net); 1222 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr); 1223 tipc_bcast_unlock(l->net); 1224 } 1225 1226 kfree_skb(skb); 1227 return 0; 1228 } 1229 1230 /* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the 1231 * inner message along with the ones in the old link's 1232 * deferdq 1233 * @l: tunnel link 1234 * @skb: TUNNEL_PROTOCOL message 1235 * @inputq: queue to put messages ready for delivery 1236 */ 1237 static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb, 1238 struct sk_buff_head *inputq) 1239 { 1240 struct sk_buff **reasm_skb = &l->failover_reasm_skb; 1241 struct sk_buff_head *fdefq = &l->failover_deferdq; 1242 struct tipc_msg *hdr = buf_msg(skb); 1243 struct sk_buff *iskb; 1244 int ipos = 0; 1245 int rc = 0; 1246 u16 seqno; 1247 1248 /* SYNCH_MSG */ 1249 if (msg_type(hdr) == SYNCH_MSG) 1250 goto drop; 1251 1252 /* FAILOVER_MSG */ 1253 if (!tipc_msg_extract(skb, &iskb, &ipos)) { 1254 pr_warn_ratelimited("Cannot extract FAILOVER_MSG, defq: %d\n", 1255 skb_queue_len(fdefq)); 1256 return rc; 1257 } 1258 1259 do { 1260 seqno = buf_seqno(iskb); 1261 1262 if (unlikely(less(seqno, l->drop_point))) { 1263 kfree_skb(iskb); 1264 continue; 1265 } 1266 1267 if (unlikely(seqno != l->drop_point)) { 1268 __tipc_skb_queue_sorted(fdefq, seqno, iskb); 1269 continue; 1270 } 1271 1272 l->drop_point++; 1273 1274 if (!tipc_data_input(l, iskb, inputq)) 1275 rc |= tipc_link_input(l, iskb, inputq, reasm_skb); 1276 if (unlikely(rc)) 1277 break; 1278 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point))); 1279 1280 drop: 1281 kfree_skb(skb); 1282 return rc; 1283 } 1284 1285 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked) 1286 { 1287 bool released = false; 1288 struct sk_buff *skb, *tmp; 1289 1290 skb_queue_walk_safe(&l->transmq, skb, tmp) { 1291 if (more(buf_seqno(skb), acked)) 1292 break; 1293 __skb_unlink(skb, &l->transmq); 1294 kfree_skb(skb); 1295 released = true; 1296 } 1297 return released; 1298 } 1299 1300 /* tipc_build_gap_ack_blks - build Gap ACK blocks 1301 * @l: tipc link that data have come with gaps in sequence if any 1302 * @data: data buffer to store the Gap ACK blocks after built 1303 * 1304 * returns the actual allocated memory size 1305 */ 1306 static u16 tipc_build_gap_ack_blks(struct tipc_link *l, void *data) 1307 { 1308 struct sk_buff *skb = skb_peek(&l->deferdq); 1309 struct tipc_gap_ack_blks *ga = data; 1310 u16 len, expect, seqno = 0; 1311 u8 n = 0; 1312 1313 if (!skb) 1314 goto exit; 1315 1316 expect = buf_seqno(skb); 1317 skb_queue_walk(&l->deferdq, skb) { 1318 seqno = buf_seqno(skb); 1319 if (unlikely(more(seqno, expect))) { 1320 ga->gacks[n].ack = htons(expect - 1); 1321 ga->gacks[n].gap = htons(seqno - expect); 1322 if (++n >= MAX_GAP_ACK_BLKS) { 1323 pr_info_ratelimited("Too few Gap ACK blocks!\n"); 1324 goto exit; 1325 } 1326 } else if (unlikely(less(seqno, expect))) { 1327 pr_warn("Unexpected skb in deferdq!\n"); 1328 continue; 1329 } 1330 expect = seqno + 1; 1331 } 1332 1333 /* last block */ 1334 ga->gacks[n].ack = htons(seqno); 1335 ga->gacks[n].gap = 0; 1336 n++; 1337 1338 exit: 1339 len = tipc_gap_ack_blks_sz(n); 1340 ga->len = htons(len); 1341 ga->gack_cnt = n; 1342 return len; 1343 } 1344 1345 /* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing 1346 * acked packets, also doing retransmissions if 1347 * gaps found 1348 * @l: tipc link with transmq queue to be advanced 1349 * @acked: seqno of last packet acked by peer without any gaps before 1350 * @gap: # of gap packets 1351 * @ga: buffer pointer to Gap ACK blocks from peer 1352 * @xmitq: queue for accumulating the retransmitted packets if any 1353 * 1354 * In case of a repeated retransmit failures, the call will return shortly 1355 * with a returned code (e.g. TIPC_LINK_DOWN_EVT) 1356 */ 1357 static int tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap, 1358 struct tipc_gap_ack_blks *ga, 1359 struct sk_buff_head *xmitq) 1360 { 1361 struct sk_buff *skb, *_skb, *tmp; 1362 struct tipc_msg *hdr; 1363 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 1364 u16 ack = l->rcv_nxt - 1; 1365 u16 seqno, n = 0; 1366 int rc = 0; 1367 1368 if (gap && link_retransmit_failure(l, l, acked + 1, &rc)) 1369 return rc; 1370 1371 skb_queue_walk_safe(&l->transmq, skb, tmp) { 1372 seqno = buf_seqno(skb); 1373 1374 next_gap_ack: 1375 if (less_eq(seqno, acked)) { 1376 /* release skb */ 1377 __skb_unlink(skb, &l->transmq); 1378 kfree_skb(skb); 1379 } else if (less_eq(seqno, acked + gap)) { 1380 /* retransmit skb */ 1381 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr)) 1382 continue; 1383 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME; 1384 1385 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC); 1386 if (!_skb) 1387 continue; 1388 hdr = buf_msg(_skb); 1389 msg_set_ack(hdr, ack); 1390 msg_set_bcast_ack(hdr, bc_ack); 1391 _skb->priority = TC_PRIO_CONTROL; 1392 __skb_queue_tail(xmitq, _skb); 1393 l->stats.retransmitted++; 1394 } else { 1395 /* retry with Gap ACK blocks if any */ 1396 if (!ga || n >= ga->gack_cnt) 1397 break; 1398 acked = ntohs(ga->gacks[n].ack); 1399 gap = ntohs(ga->gacks[n].gap); 1400 n++; 1401 goto next_gap_ack; 1402 } 1403 } 1404 1405 return 0; 1406 } 1407 1408 /* tipc_link_build_state_msg: prepare link state message for transmission 1409 * 1410 * Note that sending of broadcast ack is coordinated among nodes, to reduce 1411 * risk of ack storms towards the sender 1412 */ 1413 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 1414 { 1415 if (!l) 1416 return 0; 1417 1418 /* Broadcast ACK must be sent via a unicast link => defer to caller */ 1419 if (link_is_bc_rcvlink(l)) { 1420 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf) 1421 return 0; 1422 l->rcv_unacked = 0; 1423 1424 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */ 1425 l->snd_nxt = l->rcv_nxt; 1426 return TIPC_LINK_SND_STATE; 1427 } 1428 1429 /* Unicast ACK */ 1430 l->rcv_unacked = 0; 1431 l->stats.sent_acks++; 1432 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq); 1433 return 0; 1434 } 1435 1436 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message 1437 */ 1438 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 1439 { 1440 int mtyp = RESET_MSG; 1441 struct sk_buff *skb; 1442 1443 if (l->state == LINK_ESTABLISHING) 1444 mtyp = ACTIVATE_MSG; 1445 1446 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq); 1447 1448 /* Inform peer that this endpoint is going down if applicable */ 1449 skb = skb_peek_tail(xmitq); 1450 if (skb && (l->state == LINK_RESET)) 1451 msg_set_peer_stopping(buf_msg(skb), 1); 1452 } 1453 1454 /* tipc_link_build_nack_msg: prepare link nack message for transmission 1455 * Note that sending of broadcast NACK is coordinated among nodes, to 1456 * reduce the risk of NACK storms towards the sender 1457 */ 1458 static int tipc_link_build_nack_msg(struct tipc_link *l, 1459 struct sk_buff_head *xmitq) 1460 { 1461 u32 def_cnt = ++l->stats.deferred_recv; 1462 u32 defq_len = skb_queue_len(&l->deferdq); 1463 int match1, match2; 1464 1465 if (link_is_bc_rcvlink(l)) { 1466 match1 = def_cnt & 0xf; 1467 match2 = tipc_own_addr(l->net) & 0xf; 1468 if (match1 == match2) 1469 return TIPC_LINK_SND_STATE; 1470 return 0; 1471 } 1472 1473 if (defq_len >= 3 && !((defq_len - 3) % 16)) 1474 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq); 1475 return 0; 1476 } 1477 1478 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node 1479 * @l: the link that should handle the message 1480 * @skb: TIPC packet 1481 * @xmitq: queue to place packets to be sent after this call 1482 */ 1483 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, 1484 struct sk_buff_head *xmitq) 1485 { 1486 struct sk_buff_head *defq = &l->deferdq; 1487 struct tipc_msg *hdr = buf_msg(skb); 1488 u16 seqno, rcv_nxt, win_lim; 1489 int rc = 0; 1490 1491 /* Verify and update link state */ 1492 if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) 1493 return tipc_link_proto_rcv(l, skb, xmitq); 1494 1495 /* Don't send probe at next timeout expiration */ 1496 l->silent_intv_cnt = 0; 1497 1498 do { 1499 hdr = buf_msg(skb); 1500 seqno = msg_seqno(hdr); 1501 rcv_nxt = l->rcv_nxt; 1502 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN; 1503 1504 if (unlikely(!link_is_up(l))) { 1505 if (l->state == LINK_ESTABLISHING) 1506 rc = TIPC_LINK_UP_EVT; 1507 goto drop; 1508 } 1509 1510 /* Drop if outside receive window */ 1511 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) { 1512 l->stats.duplicates++; 1513 goto drop; 1514 } 1515 1516 /* Forward queues and wake up waiting users */ 1517 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) { 1518 l->stale_cnt = 0; 1519 tipc_link_advance_backlog(l, xmitq); 1520 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1521 link_prepare_wakeup(l); 1522 } 1523 1524 /* Defer delivery if sequence gap */ 1525 if (unlikely(seqno != rcv_nxt)) { 1526 __tipc_skb_queue_sorted(defq, seqno, skb); 1527 rc |= tipc_link_build_nack_msg(l, xmitq); 1528 break; 1529 } 1530 1531 /* Deliver packet */ 1532 l->rcv_nxt++; 1533 l->stats.recv_pkts++; 1534 1535 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL)) 1536 rc |= tipc_link_tnl_rcv(l, skb, l->inputq); 1537 else if (!tipc_data_input(l, skb, l->inputq)) 1538 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf); 1539 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN)) 1540 rc |= tipc_link_build_state_msg(l, xmitq); 1541 if (unlikely(rc & ~TIPC_LINK_SND_STATE)) 1542 break; 1543 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt))); 1544 1545 return rc; 1546 drop: 1547 kfree_skb(skb); 1548 return rc; 1549 } 1550 1551 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, 1552 bool probe_reply, u16 rcvgap, 1553 int tolerance, int priority, 1554 struct sk_buff_head *xmitq) 1555 { 1556 struct tipc_link *bcl = l->bc_rcvlink; 1557 struct sk_buff *skb; 1558 struct tipc_msg *hdr; 1559 struct sk_buff_head *dfq = &l->deferdq; 1560 bool node_up = link_is_up(bcl); 1561 struct tipc_mon_state *mstate = &l->mon_state; 1562 int dlen = 0; 1563 void *data; 1564 u16 glen = 0; 1565 1566 /* Don't send protocol message during reset or link failover */ 1567 if (tipc_link_is_blocked(l)) 1568 return; 1569 1570 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG)) 1571 return; 1572 1573 if (!skb_queue_empty(dfq)) 1574 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt; 1575 1576 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE, 1577 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ, 1578 l->addr, tipc_own_addr(l->net), 0, 0, 0); 1579 if (!skb) 1580 return; 1581 1582 hdr = buf_msg(skb); 1583 data = msg_data(hdr); 1584 msg_set_session(hdr, l->session); 1585 msg_set_bearer_id(hdr, l->bearer_id); 1586 msg_set_net_plane(hdr, l->net_plane); 1587 msg_set_next_sent(hdr, l->snd_nxt); 1588 msg_set_ack(hdr, l->rcv_nxt - 1); 1589 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1); 1590 msg_set_bc_ack_invalid(hdr, !node_up); 1591 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1592 msg_set_link_tolerance(hdr, tolerance); 1593 msg_set_linkprio(hdr, priority); 1594 msg_set_redundant_link(hdr, node_up); 1595 msg_set_seq_gap(hdr, 0); 1596 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2); 1597 1598 if (mtyp == STATE_MSG) { 1599 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO) 1600 msg_set_seqno(hdr, l->snd_nxt_state++); 1601 msg_set_seq_gap(hdr, rcvgap); 1602 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl)); 1603 msg_set_probe(hdr, probe); 1604 msg_set_is_keepalive(hdr, probe || probe_reply); 1605 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) 1606 glen = tipc_build_gap_ack_blks(l, data); 1607 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id); 1608 msg_set_size(hdr, INT_H_SIZE + glen + dlen); 1609 skb_trim(skb, INT_H_SIZE + glen + dlen); 1610 l->stats.sent_states++; 1611 l->rcv_unacked = 0; 1612 } else { 1613 /* RESET_MSG or ACTIVATE_MSG */ 1614 if (mtyp == ACTIVATE_MSG) { 1615 msg_set_dest_session_valid(hdr, 1); 1616 msg_set_dest_session(hdr, l->peer_session); 1617 } 1618 msg_set_max_pkt(hdr, l->advertised_mtu); 1619 strcpy(data, l->if_name); 1620 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME); 1621 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME); 1622 } 1623 if (probe) 1624 l->stats.sent_probes++; 1625 if (rcvgap) 1626 l->stats.sent_nacks++; 1627 skb->priority = TC_PRIO_CONTROL; 1628 __skb_queue_tail(xmitq, skb); 1629 trace_tipc_proto_build(skb, false, l->name); 1630 } 1631 1632 void tipc_link_create_dummy_tnl_msg(struct tipc_link *l, 1633 struct sk_buff_head *xmitq) 1634 { 1635 u32 onode = tipc_own_addr(l->net); 1636 struct tipc_msg *hdr, *ihdr; 1637 struct sk_buff_head tnlq; 1638 struct sk_buff *skb; 1639 u32 dnode = l->addr; 1640 1641 skb_queue_head_init(&tnlq); 1642 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG, 1643 INT_H_SIZE, BASIC_H_SIZE, 1644 dnode, onode, 0, 0, 0); 1645 if (!skb) { 1646 pr_warn("%sunable to create tunnel packet\n", link_co_err); 1647 return; 1648 } 1649 1650 hdr = buf_msg(skb); 1651 msg_set_msgcnt(hdr, 1); 1652 msg_set_bearer_id(hdr, l->peer_bearer_id); 1653 1654 ihdr = (struct tipc_msg *)msg_data(hdr); 1655 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG, 1656 BASIC_H_SIZE, dnode); 1657 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT); 1658 __skb_queue_tail(&tnlq, skb); 1659 tipc_link_xmit(l, &tnlq, xmitq); 1660 } 1661 1662 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets 1663 * with contents of the link's transmit and backlog queues. 1664 */ 1665 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, 1666 int mtyp, struct sk_buff_head *xmitq) 1667 { 1668 struct sk_buff_head *fdefq = &tnl->failover_deferdq; 1669 struct sk_buff *skb, *tnlskb; 1670 struct tipc_msg *hdr, tnlhdr; 1671 struct sk_buff_head *queue = &l->transmq; 1672 struct sk_buff_head tmpxq, tnlq; 1673 u16 pktlen, pktcnt, seqno = l->snd_nxt; 1674 1675 if (!tnl) 1676 return; 1677 1678 skb_queue_head_init(&tnlq); 1679 skb_queue_head_init(&tmpxq); 1680 1681 /* At least one packet required for safe algorithm => add dummy */ 1682 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG, 1683 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net), 1684 0, 0, TIPC_ERR_NO_PORT); 1685 if (!skb) { 1686 pr_warn("%sunable to create tunnel packet\n", link_co_err); 1687 return; 1688 } 1689 skb_queue_tail(&tnlq, skb); 1690 tipc_link_xmit(l, &tnlq, &tmpxq); 1691 __skb_queue_purge(&tmpxq); 1692 1693 /* Initialize reusable tunnel packet header */ 1694 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL, 1695 mtyp, INT_H_SIZE, l->addr); 1696 if (mtyp == SYNCH_MSG) 1697 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq)); 1698 else 1699 pktcnt = skb_queue_len(&l->transmq); 1700 pktcnt += skb_queue_len(&l->backlogq); 1701 msg_set_msgcnt(&tnlhdr, pktcnt); 1702 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id); 1703 tnl: 1704 /* Wrap each packet into a tunnel packet */ 1705 skb_queue_walk(queue, skb) { 1706 hdr = buf_msg(skb); 1707 if (queue == &l->backlogq) 1708 msg_set_seqno(hdr, seqno++); 1709 pktlen = msg_size(hdr); 1710 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE); 1711 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC); 1712 if (!tnlskb) { 1713 pr_warn("%sunable to send packet\n", link_co_err); 1714 return; 1715 } 1716 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE); 1717 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen); 1718 __skb_queue_tail(&tnlq, tnlskb); 1719 } 1720 if (queue != &l->backlogq) { 1721 queue = &l->backlogq; 1722 goto tnl; 1723 } 1724 1725 tipc_link_xmit(tnl, &tnlq, xmitq); 1726 1727 if (mtyp == FAILOVER_MSG) { 1728 tnl->drop_point = l->rcv_nxt; 1729 tnl->failover_reasm_skb = l->reasm_buf; 1730 l->reasm_buf = NULL; 1731 1732 /* Failover the link's deferdq */ 1733 if (unlikely(!skb_queue_empty(fdefq))) { 1734 pr_warn("Link failover deferdq not empty: %d!\n", 1735 skb_queue_len(fdefq)); 1736 __skb_queue_purge(fdefq); 1737 } 1738 skb_queue_splice_init(&l->deferdq, fdefq); 1739 } 1740 } 1741 1742 /** 1743 * tipc_link_failover_prepare() - prepare tnl for link failover 1744 * 1745 * This is a special version of the precursor - tipc_link_tnl_prepare(), 1746 * see the tipc_node_link_failover() for details 1747 * 1748 * @l: failover link 1749 * @tnl: tunnel link 1750 * @xmitq: queue for messages to be xmited 1751 */ 1752 void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl, 1753 struct sk_buff_head *xmitq) 1754 { 1755 struct sk_buff_head *fdefq = &tnl->failover_deferdq; 1756 1757 tipc_link_create_dummy_tnl_msg(tnl, xmitq); 1758 1759 /* This failover link enpoint was never established before, 1760 * so it has not received anything from peer. 1761 * Otherwise, it must be a normal failover situation or the 1762 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes 1763 * would have to start over from scratch instead. 1764 */ 1765 WARN_ON(l && tipc_link_is_up(l)); 1766 tnl->drop_point = 1; 1767 tnl->failover_reasm_skb = NULL; 1768 1769 /* Initiate the link's failover deferdq */ 1770 if (unlikely(!skb_queue_empty(fdefq))) { 1771 pr_warn("Link failover deferdq not empty: %d!\n", 1772 skb_queue_len(fdefq)); 1773 __skb_queue_purge(fdefq); 1774 } 1775 } 1776 1777 /* tipc_link_validate_msg(): validate message against current link state 1778 * Returns true if message should be accepted, otherwise false 1779 */ 1780 bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr) 1781 { 1782 u16 curr_session = l->peer_session; 1783 u16 session = msg_session(hdr); 1784 int mtyp = msg_type(hdr); 1785 1786 if (msg_user(hdr) != LINK_PROTOCOL) 1787 return true; 1788 1789 switch (mtyp) { 1790 case RESET_MSG: 1791 if (!l->in_session) 1792 return true; 1793 /* Accept only RESET with new session number */ 1794 return more(session, curr_session); 1795 case ACTIVATE_MSG: 1796 if (!l->in_session) 1797 return true; 1798 /* Accept only ACTIVATE with new or current session number */ 1799 return !less(session, curr_session); 1800 case STATE_MSG: 1801 /* Accept only STATE with current session number */ 1802 if (!l->in_session) 1803 return false; 1804 if (session != curr_session) 1805 return false; 1806 /* Extra sanity check */ 1807 if (!link_is_up(l) && msg_ack(hdr)) 1808 return false; 1809 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO)) 1810 return true; 1811 /* Accept only STATE with new sequence number */ 1812 return !less(msg_seqno(hdr), l->rcv_nxt_state); 1813 default: 1814 return false; 1815 } 1816 } 1817 1818 /* tipc_link_proto_rcv(): receive link level protocol message : 1819 * Note that network plane id propagates through the network, and may 1820 * change at any time. The node with lowest numerical id determines 1821 * network plane 1822 */ 1823 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, 1824 struct sk_buff_head *xmitq) 1825 { 1826 struct tipc_msg *hdr = buf_msg(skb); 1827 struct tipc_gap_ack_blks *ga = NULL; 1828 u16 rcvgap = 0; 1829 u16 ack = msg_ack(hdr); 1830 u16 gap = msg_seq_gap(hdr); 1831 u16 peers_snd_nxt = msg_next_sent(hdr); 1832 u16 peers_tol = msg_link_tolerance(hdr); 1833 u16 peers_prio = msg_linkprio(hdr); 1834 u16 rcv_nxt = l->rcv_nxt; 1835 u16 dlen = msg_data_sz(hdr); 1836 int mtyp = msg_type(hdr); 1837 bool reply = msg_probe(hdr); 1838 u16 glen = 0; 1839 void *data; 1840 char *if_name; 1841 int rc = 0; 1842 1843 trace_tipc_proto_rcv(skb, false, l->name); 1844 if (tipc_link_is_blocked(l) || !xmitq) 1845 goto exit; 1846 1847 if (tipc_own_addr(l->net) > msg_prevnode(hdr)) 1848 l->net_plane = msg_net_plane(hdr); 1849 1850 skb_linearize(skb); 1851 hdr = buf_msg(skb); 1852 data = msg_data(hdr); 1853 1854 if (!tipc_link_validate_msg(l, hdr)) { 1855 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!"); 1856 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!"); 1857 goto exit; 1858 } 1859 1860 switch (mtyp) { 1861 case RESET_MSG: 1862 case ACTIVATE_MSG: 1863 /* Complete own link name with peer's interface name */ 1864 if_name = strrchr(l->name, ':') + 1; 1865 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME) 1866 break; 1867 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME) 1868 break; 1869 strncpy(if_name, data, TIPC_MAX_IF_NAME); 1870 1871 /* Update own tolerance if peer indicates a non-zero value */ 1872 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) { 1873 l->tolerance = peers_tol; 1874 l->bc_rcvlink->tolerance = peers_tol; 1875 } 1876 /* Update own priority if peer's priority is higher */ 1877 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI)) 1878 l->priority = peers_prio; 1879 1880 /* If peer is going down we want full re-establish cycle */ 1881 if (msg_peer_stopping(hdr)) { 1882 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1883 break; 1884 } 1885 1886 /* If this endpoint was re-created while peer was ESTABLISHING 1887 * it doesn't know current session number. Force re-synch. 1888 */ 1889 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) && 1890 l->session != msg_dest_session(hdr)) { 1891 if (less(l->session, msg_dest_session(hdr))) 1892 l->session = msg_dest_session(hdr) + 1; 1893 break; 1894 } 1895 1896 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */ 1897 if (mtyp == RESET_MSG || !link_is_up(l)) 1898 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); 1899 1900 /* ACTIVATE_MSG takes up link if it was already locally reset */ 1901 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING) 1902 rc = TIPC_LINK_UP_EVT; 1903 1904 l->peer_session = msg_session(hdr); 1905 l->in_session = true; 1906 l->peer_bearer_id = msg_bearer_id(hdr); 1907 if (l->mtu > msg_max_pkt(hdr)) 1908 l->mtu = msg_max_pkt(hdr); 1909 break; 1910 1911 case STATE_MSG: 1912 l->rcv_nxt_state = msg_seqno(hdr) + 1; 1913 1914 /* Update own tolerance if peer indicates a non-zero value */ 1915 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) { 1916 l->tolerance = peers_tol; 1917 l->bc_rcvlink->tolerance = peers_tol; 1918 } 1919 /* Update own prio if peer indicates a different value */ 1920 if ((peers_prio != l->priority) && 1921 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) { 1922 l->priority = peers_prio; 1923 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 1924 } 1925 1926 l->silent_intv_cnt = 0; 1927 l->stats.recv_states++; 1928 if (msg_probe(hdr)) 1929 l->stats.recv_probes++; 1930 1931 if (!link_is_up(l)) { 1932 if (l->state == LINK_ESTABLISHING) 1933 rc = TIPC_LINK_UP_EVT; 1934 break; 1935 } 1936 1937 /* Receive Gap ACK blocks from peer if any */ 1938 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) { 1939 ga = (struct tipc_gap_ack_blks *)data; 1940 glen = ntohs(ga->len); 1941 /* sanity check: if failed, ignore Gap ACK blocks */ 1942 if (glen != tipc_gap_ack_blks_sz(ga->gack_cnt)) 1943 ga = NULL; 1944 } 1945 1946 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr, 1947 &l->mon_state, l->bearer_id); 1948 1949 /* Send NACK if peer has sent pkts we haven't received yet */ 1950 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l)) 1951 rcvgap = peers_snd_nxt - l->rcv_nxt; 1952 if (rcvgap || reply) 1953 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply, 1954 rcvgap, 0, 0, xmitq); 1955 1956 rc |= tipc_link_advance_transmq(l, ack, gap, ga, xmitq); 1957 1958 /* If NACK, retransmit will now start at right position */ 1959 if (gap) 1960 l->stats.recv_nacks++; 1961 1962 tipc_link_advance_backlog(l, xmitq); 1963 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1964 link_prepare_wakeup(l); 1965 } 1966 exit: 1967 kfree_skb(skb); 1968 return rc; 1969 } 1970 1971 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message 1972 */ 1973 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast, 1974 u16 peers_snd_nxt, 1975 struct sk_buff_head *xmitq) 1976 { 1977 struct sk_buff *skb; 1978 struct tipc_msg *hdr; 1979 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq); 1980 u16 ack = l->rcv_nxt - 1; 1981 u16 gap_to = peers_snd_nxt - 1; 1982 1983 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, 1984 0, l->addr, tipc_own_addr(l->net), 0, 0, 0); 1985 if (!skb) 1986 return false; 1987 hdr = buf_msg(skb); 1988 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1989 msg_set_bcast_ack(hdr, ack); 1990 msg_set_bcgap_after(hdr, ack); 1991 if (dfrd_skb) 1992 gap_to = buf_seqno(dfrd_skb) - 1; 1993 msg_set_bcgap_to(hdr, gap_to); 1994 msg_set_non_seq(hdr, bcast); 1995 __skb_queue_tail(xmitq, skb); 1996 return true; 1997 } 1998 1999 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints. 2000 * 2001 * Give a newly added peer node the sequence number where it should 2002 * start receiving and acking broadcast packets. 2003 */ 2004 static void tipc_link_build_bc_init_msg(struct tipc_link *l, 2005 struct sk_buff_head *xmitq) 2006 { 2007 struct sk_buff_head list; 2008 2009 __skb_queue_head_init(&list); 2010 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list)) 2011 return; 2012 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true); 2013 tipc_link_xmit(l, &list, xmitq); 2014 } 2015 2016 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer 2017 */ 2018 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr) 2019 { 2020 int mtyp = msg_type(hdr); 2021 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 2022 2023 if (link_is_up(l)) 2024 return; 2025 2026 if (msg_user(hdr) == BCAST_PROTOCOL) { 2027 l->rcv_nxt = peers_snd_nxt; 2028 l->state = LINK_ESTABLISHED; 2029 return; 2030 } 2031 2032 if (l->peer_caps & TIPC_BCAST_SYNCH) 2033 return; 2034 2035 if (msg_peer_node_is_up(hdr)) 2036 return; 2037 2038 /* Compatibility: accept older, less safe initial synch data */ 2039 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG)) 2040 l->rcv_nxt = peers_snd_nxt; 2041 } 2042 2043 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state 2044 */ 2045 int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr, 2046 struct sk_buff_head *xmitq) 2047 { 2048 struct tipc_link *snd_l = l->bc_sndlink; 2049 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 2050 u16 from = msg_bcast_ack(hdr) + 1; 2051 u16 to = from + msg_bc_gap(hdr) - 1; 2052 int rc = 0; 2053 2054 if (!link_is_up(l)) 2055 return rc; 2056 2057 if (!msg_peer_node_is_up(hdr)) 2058 return rc; 2059 2060 /* Open when peer ackowledges our bcast init msg (pkt #1) */ 2061 if (msg_ack(hdr)) 2062 l->bc_peer_is_up = true; 2063 2064 if (!l->bc_peer_is_up) 2065 return rc; 2066 2067 l->stats.recv_nacks++; 2068 2069 /* Ignore if peers_snd_nxt goes beyond receive window */ 2070 if (more(peers_snd_nxt, l->rcv_nxt + l->window)) 2071 return rc; 2072 2073 rc = tipc_link_bc_retrans(snd_l, l, from, to, xmitq); 2074 2075 l->snd_nxt = peers_snd_nxt; 2076 if (link_bc_rcv_gap(l)) 2077 rc |= TIPC_LINK_SND_STATE; 2078 2079 /* Return now if sender supports nack via STATE messages */ 2080 if (l->peer_caps & TIPC_BCAST_STATE_NACK) 2081 return rc; 2082 2083 /* Otherwise, be backwards compatible */ 2084 2085 if (!more(peers_snd_nxt, l->rcv_nxt)) { 2086 l->nack_state = BC_NACK_SND_CONDITIONAL; 2087 return 0; 2088 } 2089 2090 /* Don't NACK if one was recently sent or peeked */ 2091 if (l->nack_state == BC_NACK_SND_SUPPRESS) { 2092 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 2093 return 0; 2094 } 2095 2096 /* Conditionally delay NACK sending until next synch rcv */ 2097 if (l->nack_state == BC_NACK_SND_CONDITIONAL) { 2098 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 2099 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN) 2100 return 0; 2101 } 2102 2103 /* Send NACK now but suppress next one */ 2104 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq); 2105 l->nack_state = BC_NACK_SND_SUPPRESS; 2106 return 0; 2107 } 2108 2109 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked, 2110 struct sk_buff_head *xmitq) 2111 { 2112 struct sk_buff *skb, *tmp; 2113 struct tipc_link *snd_l = l->bc_sndlink; 2114 2115 if (!link_is_up(l) || !l->bc_peer_is_up) 2116 return; 2117 2118 if (!more(acked, l->acked)) 2119 return; 2120 2121 trace_tipc_link_bc_ack(l, l->acked, acked, &snd_l->transmq); 2122 /* Skip over packets peer has already acked */ 2123 skb_queue_walk(&snd_l->transmq, skb) { 2124 if (more(buf_seqno(skb), l->acked)) 2125 break; 2126 } 2127 2128 /* Update/release the packets peer is acking now */ 2129 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) { 2130 if (more(buf_seqno(skb), acked)) 2131 break; 2132 if (!--TIPC_SKB_CB(skb)->ackers) { 2133 __skb_unlink(skb, &snd_l->transmq); 2134 kfree_skb(skb); 2135 } 2136 } 2137 l->acked = acked; 2138 tipc_link_advance_backlog(snd_l, xmitq); 2139 if (unlikely(!skb_queue_empty(&snd_l->wakeupq))) 2140 link_prepare_wakeup(snd_l); 2141 } 2142 2143 /* tipc_link_bc_nack_rcv(): receive broadcast nack message 2144 * This function is here for backwards compatibility, since 2145 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5. 2146 */ 2147 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb, 2148 struct sk_buff_head *xmitq) 2149 { 2150 struct tipc_msg *hdr = buf_msg(skb); 2151 u32 dnode = msg_destnode(hdr); 2152 int mtyp = msg_type(hdr); 2153 u16 acked = msg_bcast_ack(hdr); 2154 u16 from = acked + 1; 2155 u16 to = msg_bcgap_to(hdr); 2156 u16 peers_snd_nxt = to + 1; 2157 int rc = 0; 2158 2159 kfree_skb(skb); 2160 2161 if (!tipc_link_is_up(l) || !l->bc_peer_is_up) 2162 return 0; 2163 2164 if (mtyp != STATE_MSG) 2165 return 0; 2166 2167 if (dnode == tipc_own_addr(l->net)) { 2168 tipc_link_bc_ack_rcv(l, acked, xmitq); 2169 rc = tipc_link_bc_retrans(l->bc_sndlink, l, from, to, xmitq); 2170 l->stats.recv_nacks++; 2171 return rc; 2172 } 2173 2174 /* Msg for other node => suppress own NACK at next sync if applicable */ 2175 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from)) 2176 l->nack_state = BC_NACK_SND_SUPPRESS; 2177 2178 return 0; 2179 } 2180 2181 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win) 2182 { 2183 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE); 2184 2185 l->window = win; 2186 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win); 2187 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2); 2188 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3); 2189 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4); 2190 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk; 2191 } 2192 2193 /** 2194 * link_reset_stats - reset link statistics 2195 * @l: pointer to link 2196 */ 2197 void tipc_link_reset_stats(struct tipc_link *l) 2198 { 2199 memset(&l->stats, 0, sizeof(l->stats)); 2200 } 2201 2202 static void link_print(struct tipc_link *l, const char *str) 2203 { 2204 struct sk_buff *hskb = skb_peek(&l->transmq); 2205 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1; 2206 u16 tail = l->snd_nxt - 1; 2207 2208 pr_info("%s Link <%s> state %x\n", str, l->name, l->state); 2209 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n", 2210 skb_queue_len(&l->transmq), head, tail, 2211 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt); 2212 } 2213 2214 /* Parse and validate nested (link) properties valid for media, bearer and link 2215 */ 2216 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]) 2217 { 2218 int err; 2219 2220 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop, 2221 tipc_nl_prop_policy, NULL); 2222 if (err) 2223 return err; 2224 2225 if (props[TIPC_NLA_PROP_PRIO]) { 2226 u32 prio; 2227 2228 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); 2229 if (prio > TIPC_MAX_LINK_PRI) 2230 return -EINVAL; 2231 } 2232 2233 if (props[TIPC_NLA_PROP_TOL]) { 2234 u32 tol; 2235 2236 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); 2237 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL)) 2238 return -EINVAL; 2239 } 2240 2241 if (props[TIPC_NLA_PROP_WIN]) { 2242 u32 win; 2243 2244 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); 2245 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN)) 2246 return -EINVAL; 2247 } 2248 2249 return 0; 2250 } 2251 2252 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s) 2253 { 2254 int i; 2255 struct nlattr *stats; 2256 2257 struct nla_map { 2258 u32 key; 2259 u32 val; 2260 }; 2261 2262 struct nla_map map[] = { 2263 {TIPC_NLA_STATS_RX_INFO, 0}, 2264 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments}, 2265 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented}, 2266 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles}, 2267 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled}, 2268 {TIPC_NLA_STATS_TX_INFO, 0}, 2269 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments}, 2270 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented}, 2271 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles}, 2272 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled}, 2273 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ? 2274 s->msg_length_counts : 1}, 2275 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts}, 2276 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total}, 2277 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]}, 2278 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]}, 2279 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]}, 2280 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]}, 2281 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]}, 2282 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]}, 2283 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]}, 2284 {TIPC_NLA_STATS_RX_STATES, s->recv_states}, 2285 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes}, 2286 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks}, 2287 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv}, 2288 {TIPC_NLA_STATS_TX_STATES, s->sent_states}, 2289 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes}, 2290 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks}, 2291 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks}, 2292 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted}, 2293 {TIPC_NLA_STATS_DUPLICATES, s->duplicates}, 2294 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs}, 2295 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz}, 2296 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ? 2297 (s->accu_queue_sz / s->queue_sz_counts) : 0} 2298 }; 2299 2300 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS); 2301 if (!stats) 2302 return -EMSGSIZE; 2303 2304 for (i = 0; i < ARRAY_SIZE(map); i++) 2305 if (nla_put_u32(skb, map[i].key, map[i].val)) 2306 goto msg_full; 2307 2308 nla_nest_end(skb, stats); 2309 2310 return 0; 2311 msg_full: 2312 nla_nest_cancel(skb, stats); 2313 2314 return -EMSGSIZE; 2315 } 2316 2317 /* Caller should hold appropriate locks to protect the link */ 2318 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg, 2319 struct tipc_link *link, int nlflags) 2320 { 2321 u32 self = tipc_own_addr(net); 2322 struct nlattr *attrs; 2323 struct nlattr *prop; 2324 void *hdr; 2325 int err; 2326 2327 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 2328 nlflags, TIPC_NL_LINK_GET); 2329 if (!hdr) 2330 return -EMSGSIZE; 2331 2332 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK); 2333 if (!attrs) 2334 goto msg_full; 2335 2336 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name)) 2337 goto attr_msg_full; 2338 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self))) 2339 goto attr_msg_full; 2340 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu)) 2341 goto attr_msg_full; 2342 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts)) 2343 goto attr_msg_full; 2344 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts)) 2345 goto attr_msg_full; 2346 2347 if (tipc_link_is_up(link)) 2348 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 2349 goto attr_msg_full; 2350 if (link->active) 2351 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE)) 2352 goto attr_msg_full; 2353 2354 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP); 2355 if (!prop) 2356 goto attr_msg_full; 2357 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 2358 goto prop_msg_full; 2359 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance)) 2360 goto prop_msg_full; 2361 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, 2362 link->window)) 2363 goto prop_msg_full; 2364 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 2365 goto prop_msg_full; 2366 nla_nest_end(msg->skb, prop); 2367 2368 err = __tipc_nl_add_stats(msg->skb, &link->stats); 2369 if (err) 2370 goto attr_msg_full; 2371 2372 nla_nest_end(msg->skb, attrs); 2373 genlmsg_end(msg->skb, hdr); 2374 2375 return 0; 2376 2377 prop_msg_full: 2378 nla_nest_cancel(msg->skb, prop); 2379 attr_msg_full: 2380 nla_nest_cancel(msg->skb, attrs); 2381 msg_full: 2382 genlmsg_cancel(msg->skb, hdr); 2383 2384 return -EMSGSIZE; 2385 } 2386 2387 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb, 2388 struct tipc_stats *stats) 2389 { 2390 int i; 2391 struct nlattr *nest; 2392 2393 struct nla_map { 2394 __u32 key; 2395 __u32 val; 2396 }; 2397 2398 struct nla_map map[] = { 2399 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts}, 2400 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments}, 2401 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented}, 2402 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles}, 2403 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled}, 2404 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts}, 2405 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments}, 2406 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented}, 2407 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles}, 2408 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled}, 2409 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks}, 2410 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv}, 2411 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks}, 2412 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks}, 2413 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted}, 2414 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates}, 2415 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs}, 2416 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz}, 2417 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ? 2418 (stats->accu_queue_sz / stats->queue_sz_counts) : 0} 2419 }; 2420 2421 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS); 2422 if (!nest) 2423 return -EMSGSIZE; 2424 2425 for (i = 0; i < ARRAY_SIZE(map); i++) 2426 if (nla_put_u32(skb, map[i].key, map[i].val)) 2427 goto msg_full; 2428 2429 nla_nest_end(skb, nest); 2430 2431 return 0; 2432 msg_full: 2433 nla_nest_cancel(skb, nest); 2434 2435 return -EMSGSIZE; 2436 } 2437 2438 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg) 2439 { 2440 int err; 2441 void *hdr; 2442 struct nlattr *attrs; 2443 struct nlattr *prop; 2444 struct tipc_net *tn = net_generic(net, tipc_net_id); 2445 u32 bc_mode = tipc_bcast_get_broadcast_mode(net); 2446 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net); 2447 struct tipc_link *bcl = tn->bcl; 2448 2449 if (!bcl) 2450 return 0; 2451 2452 tipc_bcast_lock(net); 2453 2454 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 2455 NLM_F_MULTI, TIPC_NL_LINK_GET); 2456 if (!hdr) { 2457 tipc_bcast_unlock(net); 2458 return -EMSGSIZE; 2459 } 2460 2461 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK); 2462 if (!attrs) 2463 goto msg_full; 2464 2465 /* The broadcast link is always up */ 2466 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 2467 goto attr_msg_full; 2468 2469 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST)) 2470 goto attr_msg_full; 2471 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name)) 2472 goto attr_msg_full; 2473 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0)) 2474 goto attr_msg_full; 2475 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0)) 2476 goto attr_msg_full; 2477 2478 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP); 2479 if (!prop) 2480 goto attr_msg_full; 2481 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window)) 2482 goto prop_msg_full; 2483 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode)) 2484 goto prop_msg_full; 2485 if (bc_mode & BCLINK_MODE_SEL) 2486 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO, 2487 bc_ratio)) 2488 goto prop_msg_full; 2489 nla_nest_end(msg->skb, prop); 2490 2491 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats); 2492 if (err) 2493 goto attr_msg_full; 2494 2495 tipc_bcast_unlock(net); 2496 nla_nest_end(msg->skb, attrs); 2497 genlmsg_end(msg->skb, hdr); 2498 2499 return 0; 2500 2501 prop_msg_full: 2502 nla_nest_cancel(msg->skb, prop); 2503 attr_msg_full: 2504 nla_nest_cancel(msg->skb, attrs); 2505 msg_full: 2506 tipc_bcast_unlock(net); 2507 genlmsg_cancel(msg->skb, hdr); 2508 2509 return -EMSGSIZE; 2510 } 2511 2512 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol, 2513 struct sk_buff_head *xmitq) 2514 { 2515 l->tolerance = tol; 2516 if (l->bc_rcvlink) 2517 l->bc_rcvlink->tolerance = tol; 2518 if (link_is_up(l)) 2519 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq); 2520 } 2521 2522 void tipc_link_set_prio(struct tipc_link *l, u32 prio, 2523 struct sk_buff_head *xmitq) 2524 { 2525 l->priority = prio; 2526 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq); 2527 } 2528 2529 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit) 2530 { 2531 l->abort_limit = limit; 2532 } 2533 2534 char *tipc_link_name_ext(struct tipc_link *l, char *buf) 2535 { 2536 if (!l) 2537 scnprintf(buf, TIPC_MAX_LINK_NAME, "null"); 2538 else if (link_is_bc_sndlink(l)) 2539 scnprintf(buf, TIPC_MAX_LINK_NAME, "broadcast-sender"); 2540 else if (link_is_bc_rcvlink(l)) 2541 scnprintf(buf, TIPC_MAX_LINK_NAME, 2542 "broadcast-receiver, peer %x", l->addr); 2543 else 2544 memcpy(buf, l->name, TIPC_MAX_LINK_NAME); 2545 2546 return buf; 2547 } 2548 2549 /** 2550 * tipc_link_dump - dump TIPC link data 2551 * @l: tipc link to be dumped 2552 * @dqueues: bitmask to decide if any link queue to be dumped? 2553 * - TIPC_DUMP_NONE: don't dump link queues 2554 * - TIPC_DUMP_TRANSMQ: dump link transmq queue 2555 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue 2556 * - TIPC_DUMP_DEFERDQ: dump link deferd queue 2557 * - TIPC_DUMP_INPUTQ: dump link input queue 2558 * - TIPC_DUMP_WAKEUP: dump link wakeup queue 2559 * - TIPC_DUMP_ALL: dump all the link queues above 2560 * @buf: returned buffer of dump data in format 2561 */ 2562 int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf) 2563 { 2564 int i = 0; 2565 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN; 2566 struct sk_buff_head *list; 2567 struct sk_buff *hskb, *tskb; 2568 u32 len; 2569 2570 if (!l) { 2571 i += scnprintf(buf, sz, "link data: (null)\n"); 2572 return i; 2573 } 2574 2575 i += scnprintf(buf, sz, "link data: %x", l->addr); 2576 i += scnprintf(buf + i, sz - i, " %x", l->state); 2577 i += scnprintf(buf + i, sz - i, " %u", l->in_session); 2578 i += scnprintf(buf + i, sz - i, " %u", l->session); 2579 i += scnprintf(buf + i, sz - i, " %u", l->peer_session); 2580 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt); 2581 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt); 2582 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state); 2583 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state); 2584 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps); 2585 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt); 2586 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt); 2587 i += scnprintf(buf + i, sz - i, " %u", l->prev_from); 2588 i += scnprintf(buf + i, sz - i, " %u", l->stale_cnt); 2589 i += scnprintf(buf + i, sz - i, " %u", l->acked); 2590 2591 list = &l->transmq; 2592 len = skb_queue_len(list); 2593 hskb = skb_peek(list); 2594 tskb = skb_peek_tail(list); 2595 i += scnprintf(buf + i, sz - i, " | %u %u %u", len, 2596 (hskb) ? msg_seqno(buf_msg(hskb)) : 0, 2597 (tskb) ? msg_seqno(buf_msg(tskb)) : 0); 2598 2599 list = &l->deferdq; 2600 len = skb_queue_len(list); 2601 hskb = skb_peek(list); 2602 tskb = skb_peek_tail(list); 2603 i += scnprintf(buf + i, sz - i, " | %u %u %u", len, 2604 (hskb) ? msg_seqno(buf_msg(hskb)) : 0, 2605 (tskb) ? msg_seqno(buf_msg(tskb)) : 0); 2606 2607 list = &l->backlogq; 2608 len = skb_queue_len(list); 2609 hskb = skb_peek(list); 2610 tskb = skb_peek_tail(list); 2611 i += scnprintf(buf + i, sz - i, " | %u %u %u", len, 2612 (hskb) ? msg_seqno(buf_msg(hskb)) : 0, 2613 (tskb) ? msg_seqno(buf_msg(tskb)) : 0); 2614 2615 list = l->inputq; 2616 len = skb_queue_len(list); 2617 hskb = skb_peek(list); 2618 tskb = skb_peek_tail(list); 2619 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len, 2620 (hskb) ? msg_seqno(buf_msg(hskb)) : 0, 2621 (tskb) ? msg_seqno(buf_msg(tskb)) : 0); 2622 2623 if (dqueues & TIPC_DUMP_TRANSMQ) { 2624 i += scnprintf(buf + i, sz - i, "transmq: "); 2625 i += tipc_list_dump(&l->transmq, false, buf + i); 2626 } 2627 if (dqueues & TIPC_DUMP_BACKLOGQ) { 2628 i += scnprintf(buf + i, sz - i, 2629 "backlogq: <%u %u %u %u %u>, ", 2630 l->backlog[TIPC_LOW_IMPORTANCE].len, 2631 l->backlog[TIPC_MEDIUM_IMPORTANCE].len, 2632 l->backlog[TIPC_HIGH_IMPORTANCE].len, 2633 l->backlog[TIPC_CRITICAL_IMPORTANCE].len, 2634 l->backlog[TIPC_SYSTEM_IMPORTANCE].len); 2635 i += tipc_list_dump(&l->backlogq, false, buf + i); 2636 } 2637 if (dqueues & TIPC_DUMP_DEFERDQ) { 2638 i += scnprintf(buf + i, sz - i, "deferdq: "); 2639 i += tipc_list_dump(&l->deferdq, false, buf + i); 2640 } 2641 if (dqueues & TIPC_DUMP_INPUTQ) { 2642 i += scnprintf(buf + i, sz - i, "inputq: "); 2643 i += tipc_list_dump(l->inputq, false, buf + i); 2644 } 2645 if (dqueues & TIPC_DUMP_WAKEUP) { 2646 i += scnprintf(buf + i, sz - i, "wakeup: "); 2647 i += tipc_list_dump(&l->wakeupq, false, buf + i); 2648 } 2649 2650 return i; 2651 } 2652