1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2010 Luigi Rizzo, Riccardo Panicucci, Universita` di Pisa 5 * All rights reserved 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 /* 30 * Dummynet portions related to packet handling. 31 */ 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_inet6.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/malloc.h> 40 #include <sys/mbuf.h> 41 #include <sys/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/module.h> 44 #include <sys/mutex.h> 45 #include <sys/priv.h> 46 #include <sys/proc.h> 47 #include <sys/rwlock.h> 48 #include <sys/socket.h> 49 #include <sys/time.h> 50 #include <sys/sysctl.h> 51 52 #include <net/if.h> /* IFNAMSIZ, struct ifaddr, ifq head, lock.h mutex.h */ 53 #include <net/if_var.h> /* NET_EPOCH_... */ 54 #include <net/netisr.h> 55 #include <net/vnet.h> 56 57 #include <netinet/in.h> 58 #include <netinet/ip.h> /* ip_len, ip_off */ 59 #include <netinet/ip_var.h> /* ip_output(), IP_FORWARDING */ 60 #include <netinet/ip_fw.h> 61 #include <netinet/ip_dummynet.h> 62 #include <netinet/if_ether.h> /* various ether_* routines */ 63 #include <netinet/ip6.h> /* for ip6_input, ip6_output prototypes */ 64 #include <netinet6/ip6_var.h> 65 66 #include <netpfil/ipfw/ip_fw_private.h> 67 #include <netpfil/ipfw/dn_heap.h> 68 #include <netpfil/ipfw/ip_dn_private.h> 69 #ifdef NEW_AQM 70 #include <netpfil/ipfw/dn_aqm.h> 71 #endif 72 #include <netpfil/ipfw/dn_sched.h> 73 74 /* 75 * We keep a private variable for the simulation time, but we could 76 * probably use an existing one ("softticks" in sys/kern/kern_timeout.c) 77 * instead of dn_cfg.curr_time 78 */ 79 80 struct dn_parms dn_cfg; 81 //VNET_DEFINE(struct dn_parms, _base_dn_cfg); 82 83 static long tick_last; /* Last tick duration (usec). */ 84 static long tick_delta; /* Last vs standard tick diff (usec). */ 85 static long tick_delta_sum; /* Accumulated tick difference (usec).*/ 86 static long tick_adjustment; /* Tick adjustments done. */ 87 static long tick_lost; /* Lost(coalesced) ticks number. */ 88 /* Adjusted vs non-adjusted curr_time difference (ticks). */ 89 static long tick_diff; 90 91 static unsigned long io_pkt; 92 static unsigned long io_pkt_fast; 93 94 #ifdef NEW_AQM 95 unsigned long io_pkt_drop; 96 #else 97 static unsigned long io_pkt_drop; 98 #endif 99 /* 100 * We use a heap to store entities for which we have pending timer events. 101 * The heap is checked at every tick and all entities with expired events 102 * are extracted. 103 */ 104 105 MALLOC_DEFINE(M_DUMMYNET, "dummynet", "dummynet heap"); 106 107 extern void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 108 109 #ifdef SYSCTL_NODE 110 111 /* 112 * Because of the way the SYSBEGIN/SYSEND macros work on other 113 * platforms, there should not be functions between them. 114 * So keep the handlers outside the block. 115 */ 116 static int 117 sysctl_hash_size(SYSCTL_HANDLER_ARGS) 118 { 119 int error, value; 120 121 value = dn_cfg.hash_size; 122 error = sysctl_handle_int(oidp, &value, 0, req); 123 if (error != 0 || req->newptr == NULL) 124 return (error); 125 if (value < 16 || value > 65536) 126 return (EINVAL); 127 dn_cfg.hash_size = value; 128 return (0); 129 } 130 131 static int 132 sysctl_limits(SYSCTL_HANDLER_ARGS) 133 { 134 int error; 135 long value; 136 137 if (arg2 != 0) 138 value = dn_cfg.slot_limit; 139 else 140 value = dn_cfg.byte_limit; 141 error = sysctl_handle_long(oidp, &value, 0, req); 142 143 if (error != 0 || req->newptr == NULL) 144 return (error); 145 if (arg2 != 0) { 146 if (value < 1) 147 return (EINVAL); 148 dn_cfg.slot_limit = value; 149 } else { 150 if (value < 1500) 151 return (EINVAL); 152 dn_cfg.byte_limit = value; 153 } 154 return (0); 155 } 156 157 SYSBEGIN(f4) 158 159 SYSCTL_DECL(_net_inet); 160 SYSCTL_DECL(_net_inet_ip); 161 #ifdef NEW_AQM 162 SYSCTL_NODE(_net_inet_ip, OID_AUTO, dummynet, CTLFLAG_RW, 0, "Dummynet"); 163 #else 164 static SYSCTL_NODE(_net_inet_ip, OID_AUTO, dummynet, CTLFLAG_RW, 0, "Dummynet"); 165 #endif 166 167 /* wrapper to pass dn_cfg fields to SYSCTL_* */ 168 //#define DC(x) (&(VNET_NAME(_base_dn_cfg).x)) 169 #define DC(x) (&(dn_cfg.x)) 170 /* parameters */ 171 172 173 SYSCTL_PROC(_net_inet_ip_dummynet, OID_AUTO, hash_size, 174 CTLTYPE_INT | CTLFLAG_RW, 0, 0, sysctl_hash_size, 175 "I", "Default hash table size"); 176 177 178 SYSCTL_PROC(_net_inet_ip_dummynet, OID_AUTO, pipe_slot_limit, 179 CTLTYPE_LONG | CTLFLAG_RW, 0, 1, sysctl_limits, 180 "L", "Upper limit in slots for pipe queue."); 181 SYSCTL_PROC(_net_inet_ip_dummynet, OID_AUTO, pipe_byte_limit, 182 CTLTYPE_LONG | CTLFLAG_RW, 0, 0, sysctl_limits, 183 "L", "Upper limit in bytes for pipe queue."); 184 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, io_fast, 185 CTLFLAG_RW, DC(io_fast), 0, "Enable fast dummynet io."); 186 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, debug, 187 CTLFLAG_RW, DC(debug), 0, "Dummynet debug level"); 188 189 /* RED parameters */ 190 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_lookup_depth, 191 CTLFLAG_RD, DC(red_lookup_depth), 0, "Depth of RED lookup table"); 192 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_avg_pkt_size, 193 CTLFLAG_RD, DC(red_avg_pkt_size), 0, "RED Medium packet size"); 194 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_max_pkt_size, 195 CTLFLAG_RD, DC(red_max_pkt_size), 0, "RED Max packet size"); 196 197 /* time adjustment */ 198 SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_delta, 199 CTLFLAG_RD, &tick_delta, 0, "Last vs standard tick difference (usec)."); 200 SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_delta_sum, 201 CTLFLAG_RD, &tick_delta_sum, 0, "Accumulated tick difference (usec)."); 202 SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_adjustment, 203 CTLFLAG_RD, &tick_adjustment, 0, "Tick adjustments done."); 204 SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_diff, 205 CTLFLAG_RD, &tick_diff, 0, 206 "Adjusted vs non-adjusted curr_time difference (ticks)."); 207 SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_lost, 208 CTLFLAG_RD, &tick_lost, 0, 209 "Number of ticks coalesced by dummynet taskqueue."); 210 211 /* Drain parameters */ 212 SYSCTL_UINT(_net_inet_ip_dummynet, OID_AUTO, expire, 213 CTLFLAG_RW, DC(expire), 0, "Expire empty queues/pipes"); 214 SYSCTL_UINT(_net_inet_ip_dummynet, OID_AUTO, expire_cycle, 215 CTLFLAG_RD, DC(expire_cycle), 0, "Expire cycle for queues/pipes"); 216 217 /* statistics */ 218 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, schk_count, 219 CTLFLAG_RD, DC(schk_count), 0, "Number of schedulers"); 220 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, si_count, 221 CTLFLAG_RD, DC(si_count), 0, "Number of scheduler instances"); 222 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, fsk_count, 223 CTLFLAG_RD, DC(fsk_count), 0, "Number of flowsets"); 224 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, queue_count, 225 CTLFLAG_RD, DC(queue_count), 0, "Number of queues"); 226 SYSCTL_ULONG(_net_inet_ip_dummynet, OID_AUTO, io_pkt, 227 CTLFLAG_RD, &io_pkt, 0, 228 "Number of packets passed to dummynet."); 229 SYSCTL_ULONG(_net_inet_ip_dummynet, OID_AUTO, io_pkt_fast, 230 CTLFLAG_RD, &io_pkt_fast, 0, 231 "Number of packets bypassed dummynet scheduler."); 232 SYSCTL_ULONG(_net_inet_ip_dummynet, OID_AUTO, io_pkt_drop, 233 CTLFLAG_RD, &io_pkt_drop, 0, 234 "Number of packets dropped by dummynet."); 235 #undef DC 236 SYSEND 237 238 #endif 239 240 static void dummynet_send(struct mbuf *); 241 242 /* 243 * Return the mbuf tag holding the dummynet state (it should 244 * be the first one on the list). 245 */ 246 struct dn_pkt_tag * 247 dn_tag_get(struct mbuf *m) 248 { 249 struct m_tag *mtag = m_tag_first(m); 250 #ifdef NEW_AQM 251 /* XXX: to skip ts m_tag. For Debugging only*/ 252 if (mtag != NULL && mtag->m_tag_id == DN_AQM_MTAG_TS) { 253 m_tag_delete(m,mtag); 254 mtag = m_tag_first(m); 255 D("skip TS tag"); 256 } 257 #endif 258 KASSERT(mtag != NULL && 259 mtag->m_tag_cookie == MTAG_ABI_COMPAT && 260 mtag->m_tag_id == PACKET_TAG_DUMMYNET, 261 ("packet on dummynet queue w/o dummynet tag!")); 262 return (struct dn_pkt_tag *)(mtag+1); 263 } 264 265 #ifndef NEW_AQM 266 static inline void 267 mq_append(struct mq *q, struct mbuf *m) 268 { 269 #ifdef USERSPACE 270 // buffers from netmap need to be copied 271 // XXX note that the routine is not expected to fail 272 ND("append %p to %p", m, q); 273 if (m->m_flags & M_STACK) { 274 struct mbuf *m_new; 275 void *p; 276 int l, ofs; 277 278 ofs = m->m_data - m->__m_extbuf; 279 // XXX allocate 280 MGETHDR(m_new, M_NOWAIT, MT_DATA); 281 ND("*** WARNING, volatile buf %p ext %p %d dofs %d m_new %p", 282 m, m->__m_extbuf, m->__m_extlen, ofs, m_new); 283 p = m_new->__m_extbuf; /* new pointer */ 284 l = m_new->__m_extlen; /* new len */ 285 if (l <= m->__m_extlen) { 286 panic("extlen too large"); 287 } 288 289 *m_new = *m; // copy 290 m_new->m_flags &= ~M_STACK; 291 m_new->__m_extbuf = p; // point to new buffer 292 _pkt_copy(m->__m_extbuf, p, m->__m_extlen); 293 m_new->m_data = p + ofs; 294 m = m_new; 295 } 296 #endif /* USERSPACE */ 297 if (q->head == NULL) 298 q->head = m; 299 else 300 q->tail->m_nextpkt = m; 301 q->count++; 302 q->tail = m; 303 m->m_nextpkt = NULL; 304 } 305 #endif 306 307 /* 308 * Dispose a list of packet. Use a functions so if we need to do 309 * more work, this is a central point to do it. 310 */ 311 void dn_free_pkts(struct mbuf *mnext) 312 { 313 struct mbuf *m; 314 315 while ((m = mnext) != NULL) { 316 mnext = m->m_nextpkt; 317 FREE_PKT(m); 318 } 319 } 320 321 static int 322 red_drops (struct dn_queue *q, int len) 323 { 324 /* 325 * RED algorithm 326 * 327 * RED calculates the average queue size (avg) using a low-pass filter 328 * with an exponential weighted (w_q) moving average: 329 * avg <- (1-w_q) * avg + w_q * q_size 330 * where q_size is the queue length (measured in bytes or * packets). 331 * 332 * If q_size == 0, we compute the idle time for the link, and set 333 * avg = (1 - w_q)^(idle/s) 334 * where s is the time needed for transmitting a medium-sized packet. 335 * 336 * Now, if avg < min_th the packet is enqueued. 337 * If avg > max_th the packet is dropped. Otherwise, the packet is 338 * dropped with probability P function of avg. 339 */ 340 341 struct dn_fsk *fs = q->fs; 342 int64_t p_b = 0; 343 344 /* Queue in bytes or packets? */ 345 uint32_t q_size = (fs->fs.flags & DN_QSIZE_BYTES) ? 346 q->ni.len_bytes : q->ni.length; 347 348 /* Average queue size estimation. */ 349 if (q_size != 0) { 350 /* Queue is not empty, avg <- avg + (q_size - avg) * w_q */ 351 int diff = SCALE(q_size) - q->avg; 352 int64_t v = SCALE_MUL((int64_t)diff, (int64_t)fs->w_q); 353 354 q->avg += (int)v; 355 } else { 356 /* 357 * Queue is empty, find for how long the queue has been 358 * empty and use a lookup table for computing 359 * (1 - * w_q)^(idle_time/s) where s is the time to send a 360 * (small) packet. 361 * XXX check wraps... 362 */ 363 if (q->avg) { 364 u_int t = div64((dn_cfg.curr_time - q->q_time), fs->lookup_step); 365 366 q->avg = (t < fs->lookup_depth) ? 367 SCALE_MUL(q->avg, fs->w_q_lookup[t]) : 0; 368 } 369 } 370 371 /* Should i drop? */ 372 if (q->avg < fs->min_th) { 373 q->count = -1; 374 return (0); /* accept packet */ 375 } 376 if (q->avg >= fs->max_th) { /* average queue >= max threshold */ 377 if (fs->fs.flags & DN_IS_ECN) 378 return (1); 379 if (fs->fs.flags & DN_IS_GENTLE_RED) { 380 /* 381 * According to Gentle-RED, if avg is greater than 382 * max_th the packet is dropped with a probability 383 * p_b = c_3 * avg - c_4 384 * where c_3 = (1 - max_p) / max_th 385 * c_4 = 1 - 2 * max_p 386 */ 387 p_b = SCALE_MUL((int64_t)fs->c_3, (int64_t)q->avg) - 388 fs->c_4; 389 } else { 390 q->count = -1; 391 return (1); 392 } 393 } else if (q->avg > fs->min_th) { 394 if (fs->fs.flags & DN_IS_ECN) 395 return (1); 396 /* 397 * We compute p_b using the linear dropping function 398 * p_b = c_1 * avg - c_2 399 * where c_1 = max_p / (max_th - min_th) 400 * c_2 = max_p * min_th / (max_th - min_th) 401 */ 402 p_b = SCALE_MUL((int64_t)fs->c_1, (int64_t)q->avg) - fs->c_2; 403 } 404 405 if (fs->fs.flags & DN_QSIZE_BYTES) 406 p_b = div64((p_b * len) , fs->max_pkt_size); 407 if (++q->count == 0) 408 q->random = random() & 0xffff; 409 else { 410 /* 411 * q->count counts packets arrived since last drop, so a greater 412 * value of q->count means a greater packet drop probability. 413 */ 414 if (SCALE_MUL(p_b, SCALE((int64_t)q->count)) > q->random) { 415 q->count = 0; 416 /* After a drop we calculate a new random value. */ 417 q->random = random() & 0xffff; 418 return (1); /* drop */ 419 } 420 } 421 /* End of RED algorithm. */ 422 423 return (0); /* accept */ 424 425 } 426 427 /* 428 * ECN/ECT Processing (partially adopted from altq) 429 */ 430 #ifndef NEW_AQM 431 static 432 #endif 433 int 434 ecn_mark(struct mbuf* m) 435 { 436 struct ip *ip; 437 ip = (struct ip *)mtodo(m, dn_tag_get(m)->iphdr_off); 438 439 switch (ip->ip_v) { 440 case IPVERSION: 441 { 442 uint16_t old; 443 444 if ((ip->ip_tos & IPTOS_ECN_MASK) == IPTOS_ECN_NOTECT) 445 return (0); /* not-ECT */ 446 if ((ip->ip_tos & IPTOS_ECN_MASK) == IPTOS_ECN_CE) 447 return (1); /* already marked */ 448 449 /* 450 * ecn-capable but not marked, 451 * mark CE and update checksum 452 */ 453 old = *(uint16_t *)ip; 454 ip->ip_tos |= IPTOS_ECN_CE; 455 ip->ip_sum = cksum_adjust(ip->ip_sum, old, *(uint16_t *)ip); 456 return (1); 457 } 458 #ifdef INET6 459 case (IPV6_VERSION >> 4): 460 { 461 struct ip6_hdr *ip6 = (struct ip6_hdr *)ip; 462 u_int32_t flowlabel; 463 464 flowlabel = ntohl(ip6->ip6_flow); 465 if ((flowlabel >> 28) != 6) 466 return (0); /* version mismatch! */ 467 if ((flowlabel & (IPTOS_ECN_MASK << 20)) == 468 (IPTOS_ECN_NOTECT << 20)) 469 return (0); /* not-ECT */ 470 if ((flowlabel & (IPTOS_ECN_MASK << 20)) == 471 (IPTOS_ECN_CE << 20)) 472 return (1); /* already marked */ 473 /* 474 * ecn-capable but not marked, mark CE 475 */ 476 flowlabel |= (IPTOS_ECN_CE << 20); 477 ip6->ip6_flow = htonl(flowlabel); 478 return (1); 479 } 480 #endif 481 } 482 return (0); 483 } 484 485 /* 486 * Enqueue a packet in q, subject to space and queue management policy 487 * (whose parameters are in q->fs). 488 * Update stats for the queue and the scheduler. 489 * Return 0 on success, 1 on drop. The packet is consumed anyways. 490 */ 491 int 492 dn_enqueue(struct dn_queue *q, struct mbuf* m, int drop) 493 { 494 struct dn_fs *f; 495 struct dn_flow *ni; /* stats for scheduler instance */ 496 uint64_t len; 497 498 if (q->fs == NULL || q->_si == NULL) { 499 printf("%s fs %p si %p, dropping\n", 500 __FUNCTION__, q->fs, q->_si); 501 FREE_PKT(m); 502 return 1; 503 } 504 f = &(q->fs->fs); 505 ni = &q->_si->ni; 506 len = m->m_pkthdr.len; 507 /* Update statistics, then check reasons to drop pkt. */ 508 q->ni.tot_bytes += len; 509 q->ni.tot_pkts++; 510 ni->tot_bytes += len; 511 ni->tot_pkts++; 512 if (drop) 513 goto drop; 514 if (f->plr && random() < f->plr) 515 goto drop; 516 #ifdef NEW_AQM 517 /* Call AQM enqueue function */ 518 if (q->fs->aqmfp) 519 return q->fs->aqmfp->enqueue(q ,m); 520 #endif 521 if (f->flags & DN_IS_RED && red_drops(q, m->m_pkthdr.len)) { 522 if (!(f->flags & DN_IS_ECN) || !ecn_mark(m)) 523 goto drop; 524 } 525 if (f->flags & DN_QSIZE_BYTES) { 526 if (q->ni.len_bytes > f->qsize) 527 goto drop; 528 } else if (q->ni.length >= f->qsize) { 529 goto drop; 530 } 531 mq_append(&q->mq, m); 532 q->ni.length++; 533 q->ni.len_bytes += len; 534 ni->length++; 535 ni->len_bytes += len; 536 return (0); 537 538 drop: 539 io_pkt_drop++; 540 q->ni.drops++; 541 ni->drops++; 542 FREE_PKT(m); 543 return (1); 544 } 545 546 /* 547 * Fetch packets from the delay line which are due now. If there are 548 * leftover packets, reinsert the delay line in the heap. 549 * Runs under scheduler lock. 550 */ 551 static void 552 transmit_event(struct mq *q, struct delay_line *dline, uint64_t now) 553 { 554 struct mbuf *m; 555 struct dn_pkt_tag *pkt = NULL; 556 557 dline->oid.subtype = 0; /* not in heap */ 558 while ((m = dline->mq.head) != NULL) { 559 pkt = dn_tag_get(m); 560 if (!DN_KEY_LEQ(pkt->output_time, now)) 561 break; 562 dline->mq.head = m->m_nextpkt; 563 dline->mq.count--; 564 mq_append(q, m); 565 } 566 if (m != NULL) { 567 dline->oid.subtype = 1; /* in heap */ 568 heap_insert(&dn_cfg.evheap, pkt->output_time, dline); 569 } 570 } 571 572 /* 573 * Convert the additional MAC overheads/delays into an equivalent 574 * number of bits for the given data rate. The samples are 575 * in milliseconds so we need to divide by 1000. 576 */ 577 static uint64_t 578 extra_bits(struct mbuf *m, struct dn_schk *s) 579 { 580 int index; 581 uint64_t bits; 582 struct dn_profile *pf = s->profile; 583 584 if (!pf || pf->samples_no == 0) 585 return 0; 586 index = random() % pf->samples_no; 587 bits = div64((uint64_t)pf->samples[index] * s->link.bandwidth, 1000); 588 if (index >= pf->loss_level) { 589 struct dn_pkt_tag *dt = dn_tag_get(m); 590 if (dt) 591 dt->dn_dir = DIR_DROP; 592 } 593 return bits; 594 } 595 596 /* 597 * Send traffic from a scheduler instance due by 'now'. 598 * Return a pointer to the head of the queue. 599 */ 600 static struct mbuf * 601 serve_sched(struct mq *q, struct dn_sch_inst *si, uint64_t now) 602 { 603 struct mq def_q; 604 struct dn_schk *s = si->sched; 605 struct mbuf *m = NULL; 606 int delay_line_idle = (si->dline.mq.head == NULL); 607 int done, bw; 608 609 if (q == NULL) { 610 q = &def_q; 611 q->head = NULL; 612 } 613 614 bw = s->link.bandwidth; 615 si->kflags &= ~DN_ACTIVE; 616 617 if (bw > 0) 618 si->credit += (now - si->sched_time) * bw; 619 else 620 si->credit = 0; 621 si->sched_time = now; 622 done = 0; 623 while (si->credit >= 0 && (m = s->fp->dequeue(si)) != NULL) { 624 uint64_t len_scaled; 625 626 done++; 627 len_scaled = (bw == 0) ? 0 : hz * 628 (m->m_pkthdr.len * 8 + extra_bits(m, s)); 629 si->credit -= len_scaled; 630 /* Move packet in the delay line */ 631 dn_tag_get(m)->output_time = dn_cfg.curr_time + s->link.delay ; 632 mq_append(&si->dline.mq, m); 633 } 634 635 /* 636 * If credit >= 0 the instance is idle, mark time. 637 * Otherwise put back in the heap, and adjust the output 638 * time of the last inserted packet, m, which was too early. 639 */ 640 if (si->credit >= 0) { 641 si->idle_time = now; 642 } else { 643 uint64_t t; 644 KASSERT (bw > 0, ("bw=0 and credit<0 ?")); 645 t = div64(bw - 1 - si->credit, bw); 646 if (m) 647 dn_tag_get(m)->output_time += t; 648 si->kflags |= DN_ACTIVE; 649 heap_insert(&dn_cfg.evheap, now + t, si); 650 } 651 if (delay_line_idle && done) 652 transmit_event(q, &si->dline, now); 653 return q->head; 654 } 655 656 /* 657 * The timer handler for dummynet. Time is computed in ticks, but 658 * but the code is tolerant to the actual rate at which this is called. 659 * Once complete, the function reschedules itself for the next tick. 660 */ 661 void 662 dummynet_task(void *context, int pending) 663 { 664 struct timeval t; 665 struct mq q = { NULL, NULL }; /* queue to accumulate results */ 666 667 CURVNET_SET((struct vnet *)context); 668 669 DN_BH_WLOCK(); 670 671 /* Update number of lost(coalesced) ticks. */ 672 tick_lost += pending - 1; 673 674 getmicrouptime(&t); 675 /* Last tick duration (usec). */ 676 tick_last = (t.tv_sec - dn_cfg.prev_t.tv_sec) * 1000000 + 677 (t.tv_usec - dn_cfg.prev_t.tv_usec); 678 /* Last tick vs standard tick difference (usec). */ 679 tick_delta = (tick_last * hz - 1000000) / hz; 680 /* Accumulated tick difference (usec). */ 681 tick_delta_sum += tick_delta; 682 683 dn_cfg.prev_t = t; 684 685 /* 686 * Adjust curr_time if the accumulated tick difference is 687 * greater than the 'standard' tick. Since curr_time should 688 * be monotonically increasing, we do positive adjustments 689 * as required, and throttle curr_time in case of negative 690 * adjustment. 691 */ 692 dn_cfg.curr_time++; 693 if (tick_delta_sum - tick >= 0) { 694 int diff = tick_delta_sum / tick; 695 696 dn_cfg.curr_time += diff; 697 tick_diff += diff; 698 tick_delta_sum %= tick; 699 tick_adjustment++; 700 } else if (tick_delta_sum + tick <= 0) { 701 dn_cfg.curr_time--; 702 tick_diff--; 703 tick_delta_sum += tick; 704 tick_adjustment++; 705 } 706 707 /* serve pending events, accumulate in q */ 708 for (;;) { 709 struct dn_id *p; /* generic parameter to handler */ 710 711 if (dn_cfg.evheap.elements == 0 || 712 DN_KEY_LT(dn_cfg.curr_time, HEAP_TOP(&dn_cfg.evheap)->key)) 713 break; 714 p = HEAP_TOP(&dn_cfg.evheap)->object; 715 heap_extract(&dn_cfg.evheap, NULL); 716 717 if (p->type == DN_SCH_I) { 718 serve_sched(&q, (struct dn_sch_inst *)p, dn_cfg.curr_time); 719 } else { /* extracted a delay line */ 720 transmit_event(&q, (struct delay_line *)p, dn_cfg.curr_time); 721 } 722 } 723 if (dn_cfg.expire && ++dn_cfg.expire_cycle >= dn_cfg.expire) { 724 dn_cfg.expire_cycle = 0; 725 dn_drain_scheduler(); 726 dn_drain_queue(); 727 } 728 729 dn_reschedule(); 730 DN_BH_WUNLOCK(); 731 if (q.head != NULL) 732 dummynet_send(q.head); 733 CURVNET_RESTORE(); 734 } 735 736 /* 737 * forward a chain of packets to the proper destination. 738 * This runs outside the dummynet lock. 739 */ 740 static void 741 dummynet_send(struct mbuf *m) 742 { 743 struct mbuf *n; 744 745 NET_EPOCH_ASSERT(); 746 747 for (; m != NULL; m = n) { 748 struct ifnet *ifp = NULL; /* gcc 3.4.6 complains */ 749 struct m_tag *tag; 750 int dst; 751 752 n = m->m_nextpkt; 753 m->m_nextpkt = NULL; 754 tag = m_tag_first(m); 755 if (tag == NULL) { /* should not happen */ 756 dst = DIR_DROP; 757 } else { 758 struct dn_pkt_tag *pkt = dn_tag_get(m); 759 /* extract the dummynet info, rename the tag 760 * to carry reinject info. 761 */ 762 if (pkt->dn_dir == (DIR_OUT | PROTO_LAYER2) && 763 pkt->ifp == NULL) { 764 dst = DIR_DROP; 765 } else { 766 dst = pkt->dn_dir; 767 ifp = pkt->ifp; 768 tag->m_tag_cookie = MTAG_IPFW_RULE; 769 tag->m_tag_id = 0; 770 } 771 } 772 773 switch (dst) { 774 case DIR_OUT: 775 ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL); 776 break ; 777 778 case DIR_IN : 779 netisr_dispatch(NETISR_IP, m); 780 break; 781 782 #ifdef INET6 783 case DIR_IN | PROTO_IPV6: 784 netisr_dispatch(NETISR_IPV6, m); 785 break; 786 787 case DIR_OUT | PROTO_IPV6: 788 ip6_output(m, NULL, NULL, IPV6_FORWARDING, NULL, NULL, NULL); 789 break; 790 #endif 791 792 case DIR_FWD | PROTO_IFB: /* DN_TO_IFB_FWD: */ 793 if (bridge_dn_p != NULL) 794 ((*bridge_dn_p)(m, ifp)); 795 else 796 printf("dummynet: if_bridge not loaded\n"); 797 798 break; 799 800 case DIR_IN | PROTO_LAYER2: /* DN_TO_ETH_DEMUX: */ 801 /* 802 * The Ethernet code assumes the Ethernet header is 803 * contiguous in the first mbuf header. 804 * Insure this is true. 805 */ 806 if (m->m_len < ETHER_HDR_LEN && 807 (m = m_pullup(m, ETHER_HDR_LEN)) == NULL) { 808 printf("dummynet/ether: pullup failed, " 809 "dropping packet\n"); 810 break; 811 } 812 ether_demux(m->m_pkthdr.rcvif, m); 813 break; 814 815 case DIR_OUT | PROTO_LAYER2: /* DN_TO_ETH_OUT: */ 816 ether_output_frame(ifp, m); 817 break; 818 819 case DIR_DROP: 820 /* drop the packet after some time */ 821 FREE_PKT(m); 822 break; 823 824 default: 825 printf("dummynet: bad switch %d!\n", dst); 826 FREE_PKT(m); 827 break; 828 } 829 } 830 } 831 832 static inline int 833 tag_mbuf(struct mbuf *m, int dir, struct ip_fw_args *fwa) 834 { 835 struct dn_pkt_tag *dt; 836 struct m_tag *mtag; 837 838 mtag = m_tag_get(PACKET_TAG_DUMMYNET, 839 sizeof(*dt), M_NOWAIT | M_ZERO); 840 if (mtag == NULL) 841 return 1; /* Cannot allocate packet header. */ 842 m_tag_prepend(m, mtag); /* Attach to mbuf chain. */ 843 dt = (struct dn_pkt_tag *)(mtag + 1); 844 dt->rule = fwa->rule; 845 dt->rule.info &= IPFW_ONEPASS; /* only keep this info */ 846 dt->dn_dir = dir; 847 dt->ifp = fwa->flags & IPFW_ARGS_OUT ? fwa->ifp : NULL; 848 /* dt->output tame is updated as we move through */ 849 dt->output_time = dn_cfg.curr_time; 850 dt->iphdr_off = (dir & PROTO_LAYER2) ? ETHER_HDR_LEN : 0; 851 return 0; 852 } 853 854 855 /* 856 * dummynet hook for packets. 857 * We use the argument to locate the flowset fs and the sched_set sch 858 * associated to it. The we apply flow_mask and sched_mask to 859 * determine the queue and scheduler instances. 860 */ 861 int 862 dummynet_io(struct mbuf **m0, struct ip_fw_args *fwa) 863 { 864 struct mbuf *m = *m0; 865 struct dn_fsk *fs = NULL; 866 struct dn_sch_inst *si; 867 struct dn_queue *q = NULL; /* default */ 868 int fs_id, dir; 869 870 fs_id = (fwa->rule.info & IPFW_INFO_MASK) + 871 ((fwa->rule.info & IPFW_IS_PIPE) ? 2*DN_MAX_ID : 0); 872 /* XXXGL: convert args to dir */ 873 if (fwa->flags & IPFW_ARGS_IN) 874 dir = DIR_IN; 875 else 876 dir = DIR_OUT; 877 if (fwa->flags & IPFW_ARGS_ETHER) 878 dir |= PROTO_LAYER2; 879 else if (fwa->flags & IPFW_ARGS_IP6) 880 dir |= PROTO_IPV6; 881 DN_BH_WLOCK(); 882 io_pkt++; 883 /* we could actually tag outside the lock, but who cares... */ 884 if (tag_mbuf(m, dir, fwa)) 885 goto dropit; 886 if (dn_cfg.busy) { 887 /* if the upper half is busy doing something expensive, 888 * lets queue the packet and move forward 889 */ 890 mq_append(&dn_cfg.pending, m); 891 m = *m0 = NULL; /* consumed */ 892 goto done; /* already active, nothing to do */ 893 } 894 /* XXX locate_flowset could be optimised with a direct ref. */ 895 fs = dn_ht_find(dn_cfg.fshash, fs_id, 0, NULL); 896 if (fs == NULL) 897 goto dropit; /* This queue/pipe does not exist! */ 898 if (fs->sched == NULL) /* should not happen */ 899 goto dropit; 900 /* find scheduler instance, possibly applying sched_mask */ 901 si = ipdn_si_find(fs->sched, &(fwa->f_id)); 902 if (si == NULL) 903 goto dropit; 904 /* 905 * If the scheduler supports multiple queues, find the right one 906 * (otherwise it will be ignored by enqueue). 907 */ 908 if (fs->sched->fp->flags & DN_MULTIQUEUE) { 909 q = ipdn_q_find(fs, si, &(fwa->f_id)); 910 if (q == NULL) 911 goto dropit; 912 } 913 if (fs->sched->fp->enqueue(si, q, m)) { 914 /* packet was dropped by enqueue() */ 915 m = *m0 = NULL; 916 917 /* dn_enqueue already increases io_pkt_drop */ 918 io_pkt_drop--; 919 920 goto dropit; 921 } 922 923 if (si->kflags & DN_ACTIVE) { 924 m = *m0 = NULL; /* consumed */ 925 goto done; /* already active, nothing to do */ 926 } 927 928 /* compute the initial allowance */ 929 if (si->idle_time < dn_cfg.curr_time) { 930 /* Do this only on the first packet on an idle pipe */ 931 struct dn_link *p = &fs->sched->link; 932 933 si->sched_time = dn_cfg.curr_time; 934 si->credit = dn_cfg.io_fast ? p->bandwidth : 0; 935 if (p->burst) { 936 uint64_t burst = (dn_cfg.curr_time - si->idle_time) * p->bandwidth; 937 if (burst > p->burst) 938 burst = p->burst; 939 si->credit += burst; 940 } 941 } 942 /* pass through scheduler and delay line */ 943 m = serve_sched(NULL, si, dn_cfg.curr_time); 944 945 /* optimization -- pass it back to ipfw for immediate send */ 946 /* XXX Don't call dummynet_send() if scheduler return the packet 947 * just enqueued. This avoid a lock order reversal. 948 * 949 */ 950 if (/*dn_cfg.io_fast &&*/ m == *m0 && (dir & PROTO_LAYER2) == 0 ) { 951 /* fast io, rename the tag * to carry reinject info. */ 952 struct m_tag *tag = m_tag_first(m); 953 954 tag->m_tag_cookie = MTAG_IPFW_RULE; 955 tag->m_tag_id = 0; 956 io_pkt_fast++; 957 if (m->m_nextpkt != NULL) { 958 printf("dummynet: fast io: pkt chain detected!\n"); 959 m->m_nextpkt = NULL; 960 } 961 m = NULL; 962 } else { 963 *m0 = NULL; 964 } 965 done: 966 DN_BH_WUNLOCK(); 967 if (m) 968 dummynet_send(m); 969 return 0; 970 971 dropit: 972 io_pkt_drop++; 973 DN_BH_WUNLOCK(); 974 if (m) 975 FREE_PKT(m); 976 *m0 = NULL; 977 return (fs && (fs->fs.flags & DN_NOERROR)) ? 0 : ENOBUFS; 978 } 979