sys/netinet/tcp_ratelimit.c

   1 /*-
   2  *
   3  * SPDX-License-Identifier: BSD-3-Clause
   4  *
   5  * Copyright (c) 2018-2019
   6  *      Netflix Inc.
   7  *      All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  *
  30  */
  31 /**
  32  * Author: Randall Stewart <rrs@netflix.com>
  33  */
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37 #include "opt_inet.h"
  38 #include "opt_inet6.h"
  39 #include "opt_ipsec.h"
  40 #include "opt_tcpdebug.h"
  41 #include "opt_ratelimit.h"
  42 #include <sys/param.h>
  43 #include <sys/kernel.h>
  44 #include <sys/malloc.h>
  45 #include <sys/mbuf.h>
  46 #include <sys/socket.h>
  47 #include <sys/socketvar.h>
  48 #include <sys/sysctl.h>
  49 #include <sys/eventhandler.h>
  50 #include <sys/mutex.h>
  51 #include <sys/ck.h>
  52 #define TCPSTATES               /* for logging */
  53 #include <netinet/in.h>
  54 #include <netinet/in_pcb.h>
  55 #include <netinet/tcp_var.h>
  56 #ifdef INET6
  57 #include <netinet6/tcp6_var.h>
  58 #endif
  59 #include <netinet/tcp_ratelimit.h>
  60 #ifndef USECS_IN_SECOND
  61 #define USECS_IN_SECOND 1000000
  62 #endif
  63 /*
  64  * For the purposes of each send, what is the size
  65  * of an ethernet frame.
  66  */
  67 #ifndef ETHERNET_SEGMENT_SIZE
  68 #define ETHERNET_SEGMENT_SIZE 1500
  69 #endif
  70 MALLOC_DEFINE(M_TCPPACE, "tcp_hwpace", "TCP Hardware pacing memory");
  71 #ifdef RATELIMIT
  72
  73 #define COMMON_RATE 180500
  74 uint64_t desired_rates[] = {
  75         62500,                  /* 500Kbps */
  76         180500,                 /* 1.44Mpbs */
  77         375000,                 /* 3Mbps */
  78         500000,                 /* 4Mbps */
  79         625000,                 /* 5Mbps */
  80         750000,                 /* 6Mbps */
  81         1000000,                /* 8Mbps */
  82         1250000,                /* 10Mbps */
  83         2500000,                /* 20Mbps */
  84         3750000,                /* 30Mbps */
  85         5000000,                /* 40Meg */
  86         6250000,                /* 50Mbps */
  87         12500000,               /* 100Mbps */
  88         25000000,               /* 200Mbps */
  89         50000000,               /* 400Mbps */
  90         100000000,              /* 800Mbps */
  91         12500,                  /* 100kbps */
  92         25000,                  /* 200kbps */
  93         875000,                 /* 7Mbps */
  94         1125000,                /* 9Mbps */
  95         1875000,                /* 15Mbps */
  96         3125000,                /* 25Mbps */
  97         8125000,                /* 65Mbps */
  98         10000000,               /* 80Mbps */
  99         18750000,               /* 150Mbps */
 100         20000000,               /* 250Mbps */
 101         37500000,               /* 350Mbps */
 102         62500000,               /* 500Mbps */
 103         78125000,               /* 625Mbps */
 104         125000000,              /* 1Gbps */
 105 };
 106 #define MAX_HDWR_RATES (sizeof(desired_rates)/sizeof(uint64_t))
 107 #define RS_ORDERED_COUNT 16     /*
 108                                  * Number that are in order
 109                                  * at the beginning of the table,
 110                                  * over this a sort is required.
 111                                  */
 112 #define RS_NEXT_ORDER_GROUP 16  /*
 113                                  * The point in our table where
 114                                  * we come fill in a second ordered
 115                                  * group (index wise means -1).
 116                                  */
 117 #define ALL_HARDWARE_RATES 1004 /*
 118                                  * 1Meg - 1Gig in 1 Meg steps
 119                                  * plus 100, 200k  and 500k and
 120                                  * 10Gig
 121                                  */
 122
 123 #define RS_ONE_MEGABIT_PERSEC 1000000
 124 #define RS_ONE_GIGABIT_PERSEC 1000000000
 125 #define RS_TEN_GIGABIT_PERSEC 10000000000
 126
 127 static struct head_tcp_rate_set int_rs;
 128 static struct mtx rs_mtx;
 129 uint32_t rs_number_alive;
 130 uint32_t rs_number_dead;
 131
 132 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, rl, CTLFLAG_RW, 0,
 133     "TCP Ratelimit stats");
 134 SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, alive, CTLFLAG_RW,
 135     &rs_number_alive, 0,
 136     "Number of interfaces initialized for ratelimiting");
 137 SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, dead, CTLFLAG_RW,
 138     &rs_number_dead, 0,
 139     "Number of interfaces departing from ratelimiting");
 140
 141 static void
 142 rl_add_syctl_entries(struct sysctl_oid *rl_sysctl_root, struct tcp_rate_set *rs)
 143 {
 144         /*
 145          * Add sysctl entries for thus interface.
 146          */
 147         if (rs->rs_flags & RS_INTF_NO_SUP) {
 148                 SYSCTL_ADD_S32(&rs->sysctl_ctx,
 149                    SYSCTL_CHILDREN(rl_sysctl_root),
 150                    OID_AUTO, "disable", CTLFLAG_RD,
 151                    &rs->rs_disable, 0,
 152                    "Disable this interface from new hdwr limiting?");
 153         } else {
 154                 SYSCTL_ADD_S32(&rs->sysctl_ctx,
 155                    SYSCTL_CHILDREN(rl_sysctl_root),
 156                    OID_AUTO, "disable", CTLFLAG_RW,
 157                    &rs->rs_disable, 0,
 158                    "Disable this interface from new hdwr limiting?");
 159         }
 160         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 161             SYSCTL_CHILDREN(rl_sysctl_root),
 162             OID_AUTO, "minseg", CTLFLAG_RW,
 163             &rs->rs_min_seg, 0,
 164             "What is the minimum we need to send on this interface?");
 165         SYSCTL_ADD_U64(&rs->sysctl_ctx,
 166             SYSCTL_CHILDREN(rl_sysctl_root),
 167             OID_AUTO, "flow_limit", CTLFLAG_RW,
 168             &rs->rs_flow_limit, 0,
 169             "What is the limit for number of flows (0=unlimited)?");
 170         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 171             SYSCTL_CHILDREN(rl_sysctl_root),
 172             OID_AUTO, "highest", CTLFLAG_RD,
 173             &rs->rs_highest_valid, 0,
 174             "Highest valid rate");
 175         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 176             SYSCTL_CHILDREN(rl_sysctl_root),
 177             OID_AUTO, "lowest", CTLFLAG_RD,
 178             &rs->rs_lowest_valid, 0,
 179             "Lowest valid rate");
 180         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 181             SYSCTL_CHILDREN(rl_sysctl_root),
 182             OID_AUTO, "flags", CTLFLAG_RD,
 183             &rs->rs_flags, 0,
 184             "What lags are on the entry?");
 185         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 186             SYSCTL_CHILDREN(rl_sysctl_root),
 187             OID_AUTO, "numrates", CTLFLAG_RD,
 188             &rs->rs_rate_cnt, 0,
 189             "How many rates re there?");
 190         SYSCTL_ADD_U64(&rs->sysctl_ctx,
 191             SYSCTL_CHILDREN(rl_sysctl_root),
 192             OID_AUTO, "flows_using", CTLFLAG_RD,
 193             &rs->rs_flows_using, 0,
 194             "How many flows are using this interface now?");
 195 #ifdef DETAILED_RATELIMIT_SYSCTL
 196         if (rs->rs_rlt && rs->rs_rate_cnt > 0) {
 197                 /*  Lets display the rates */
 198                 int i;
 199                 struct sysctl_oid *rl_rates;
 200                 struct sysctl_oid *rl_rate_num;
 201                 char rate_num[16];
 202                 rl_rates = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 203                                             SYSCTL_CHILDREN(rl_sysctl_root),
 204                                             OID_AUTO,
 205                                             "rate",
 206                                             CTLFLAG_RW, 0,
 207                                             "Ratelist");
 208                 for( i = 0; i < rs->rs_rate_cnt; i++) {
 209                         sprintf(rate_num, "%d", i);
 210                         rl_rate_num = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 211                                             SYSCTL_CHILDREN(rl_rates),
 212                                             OID_AUTO,
 213                                             rate_num,
 214                                             CTLFLAG_RW, 0,
 215                                             "Individual Rate");
 216                         SYSCTL_ADD_U32(&rs->sysctl_ctx,
 217                                        SYSCTL_CHILDREN(rl_rate_num),
 218                                        OID_AUTO, "flags", CTLFLAG_RD,
 219                                        &rs->rs_rlt[i].flags, 0,
 220                                        "Flags on this rate");
 221                         SYSCTL_ADD_U32(&rs->sysctl_ctx,
 222                                        SYSCTL_CHILDREN(rl_rate_num),
 223                                        OID_AUTO, "pacetime", CTLFLAG_RD,
 224                                        &rs->rs_rlt[i].time_between, 0,
 225                                        "Time hardware inserts between 1500 byte sends");
 226                         SYSCTL_ADD_U64(&rs->sysctl_ctx,
 227                                        SYSCTL_CHILDREN(rl_rate_num),
 228                                        OID_AUTO, "rate", CTLFLAG_RD,
 229                                        &rs->rs_rlt[i].rate, 0,
 230                                        "Rate in bytes per second");
 231                 }
 232         }
 233 #endif
 234 }
 235
 236 static void
 237 rs_destroy(epoch_context_t ctx)
 238 {
 239         struct tcp_rate_set *rs;
 240         bool do_free_rs;
 241
 242         rs = __containerof(ctx, struct tcp_rate_set, rs_epoch_ctx);
 243
 244         mtx_lock(&rs_mtx);
 245         rs->rs_flags &= ~RS_FUNERAL_SCHD;
 246         /*
 247          * In theory its possible (but unlikely)
 248          * that while the delete was occuring
 249          * and we were applying the DEAD flag
 250          * someone slipped in and found the
 251          * interface in a lookup. While we
 252          * decided rs_flows_using were 0 and
 253          * scheduling the epoch_call, the other
 254          * thread incremented rs_flow_using. This
 255          * is because users have a pointer and
 256          * we only use the rs_flows_using in an
 257          * atomic fashion, i.e. the other entities
 258          * are not protected. To assure this did
 259          * not occur, we check rs_flows_using here
 260          * before deleting.
 261          */
 262         do_free_rs = (rs->rs_flows_using == 0);
 263         rs_number_dead--;
 264         mtx_unlock(&rs_mtx);
 265
 266         if (do_free_rs) {
 267                 sysctl_ctx_free(&rs->sysctl_ctx);
 268                 free(rs->rs_rlt, M_TCPPACE);
 269                 free(rs, M_TCPPACE);
 270         }
 271 }
 272
 273 static void
 274 rs_defer_destroy(struct tcp_rate_set *rs)
 275 {
 276
 277         mtx_assert(&rs_mtx, MA_OWNED);
 278
 279         /* Check if already pending. */
 280         if (rs->rs_flags & RS_FUNERAL_SCHD)
 281                 return;
 282
 283         rs_number_dead++;
 284
 285         /* Set flag to only defer once. */
 286         rs->rs_flags |= RS_FUNERAL_SCHD;
 287         epoch_call(net_epoch, &rs->rs_epoch_ctx, rs_destroy);
 288 }
 289
 290 #ifdef INET
 291 extern counter_u64_t rate_limit_set_ok;
 292 extern counter_u64_t rate_limit_active;
 293 extern counter_u64_t rate_limit_alloc_fail;
 294 #endif
 295
 296 static int
 297 rl_attach_txrtlmt(struct ifnet *ifp,
 298     uint32_t flowtype,
 299     int flowid,
 300     uint64_t cfg_rate,
 301     struct m_snd_tag **tag)
 302 {
 303         int error;
 304         union if_snd_tag_alloc_params params = {
 305                 .rate_limit.hdr.type = IF_SND_TAG_TYPE_RATE_LIMIT,
 306                 .rate_limit.hdr.flowid = flowid,
 307                 .rate_limit.hdr.flowtype = flowtype,
 308                 .rate_limit.max_rate = cfg_rate,
 309                 .rate_limit.flags = M_NOWAIT,
 310         };
 311
 312         if (ifp->if_snd_tag_alloc == NULL) {
 313                 error = EOPNOTSUPP;
 314         } else {
 315                 error = ifp->if_snd_tag_alloc(ifp, &params, tag);
 316 #ifdef INET
 317                 if (error == 0) {
 318                         if_ref((*tag)->ifp);
 319                         counter_u64_add(rate_limit_set_ok, 1);
 320                         counter_u64_add(rate_limit_active, 1);
 321                 } else
 322                         counter_u64_add(rate_limit_alloc_fail, 1);
 323 #endif
 324         }
 325         return (error);
 326 }
 327
 328 static void
 329 populate_canned_table(struct tcp_rate_set *rs, const uint64_t *rate_table_act)
 330 {
 331         /*
 332          * The internal table is "special", it
 333          * is two seperate ordered tables that
 334          * must be merged. We get here when the
 335          * adapter specifies a number of rates that
 336          * covers both ranges in the table in some
 337          * form.
 338          */
 339         int i, at_low, at_high;
 340         uint8_t low_disabled = 0, high_disabled = 0;
 341
 342         for(i = 0, at_low = 0, at_high = RS_NEXT_ORDER_GROUP; i < rs->rs_rate_cnt; i++) {
 343                 rs->rs_rlt[i].flags = 0;
 344                 rs->rs_rlt[i].time_between = 0;
 345                 if ((low_disabled == 0) &&
 346                     (high_disabled ||
 347                      (rate_table_act[at_low] < rate_table_act[at_high]))) {
 348                         rs->rs_rlt[i].rate = rate_table_act[at_low];
 349                         at_low++;
 350                         if (at_low == RS_NEXT_ORDER_GROUP)
 351                                 low_disabled = 1;
 352                 } else if (high_disabled == 0) {
 353                         rs->rs_rlt[i].rate = rate_table_act[at_high];
 354                         at_high++;
 355                         if (at_high == MAX_HDWR_RATES)
 356                                 high_disabled = 1;
 357                 }
 358         }
 359 }
 360
 361 static struct tcp_rate_set *
 362 rt_setup_new_rs(struct ifnet *ifp, int *error)
 363 {
 364         struct tcp_rate_set *rs;
 365         const uint64_t *rate_table_act;
 366         uint64_t lentim, res;
 367         size_t sz;
 368         uint32_t hash_type;
 369         int i;
 370         struct if_ratelimit_query_results rl;
 371         struct sysctl_oid *rl_sysctl_root;
 372         /*
 373          * We expect to enter with the
 374          * mutex locked.
 375          */
 376
 377         if (ifp->if_ratelimit_query == NULL) {
 378                 /*
 379                  * We can do nothing if we cannot
 380                  * get a query back from the driver.
 381                  */
 382                 return (NULL);
 383         }
 384         rs = malloc(sizeof(struct tcp_rate_set), M_TCPPACE, M_NOWAIT | M_ZERO);
 385         if (rs == NULL) {
 386                 if (error)
 387                         *error = ENOMEM;
 388                 return (NULL);
 389         }
 390         rl.flags = RT_NOSUPPORT;
 391         ifp->if_ratelimit_query(ifp, &rl);
 392         if (rl.flags & RT_IS_UNUSABLE) {
 393                 /*
 394                  * The interface does not really support
 395                  * the rate-limiting.
 396                  */
 397                 memset(rs, 0, sizeof(struct tcp_rate_set));
 398                 rs->rs_ifp = ifp;
 399                 rs->rs_if_dunit = ifp->if_dunit;
 400                 rs->rs_flags = RS_INTF_NO_SUP;
 401                 rs->rs_disable = 1;
 402                 rs_number_alive++;
 403                 sysctl_ctx_init(&rs->sysctl_ctx);
 404                 rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 405                     SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl),
 406                     OID_AUTO,
 407                     rs->rs_ifp->if_xname,
 408                     CTLFLAG_RW, 0,
 409                     "");
 410                 rl_add_syctl_entries(rl_sysctl_root, rs);
 411                 mtx_lock(&rs_mtx);
 412                 CK_LIST_INSERT_HEAD(&int_rs, rs, next);
 413                 mtx_unlock(&rs_mtx);
 414                 return (rs);
 415         } else if ((rl.flags & RT_IS_INDIRECT) == RT_IS_INDIRECT) {
 416                 memset(rs, 0, sizeof(struct tcp_rate_set));
 417                 rs->rs_ifp = ifp;
 418                 rs->rs_if_dunit = ifp->if_dunit;
 419                 rs->rs_flags = RS_IS_DEFF;
 420                 rs_number_alive++;
 421                 sysctl_ctx_init(&rs->sysctl_ctx);
 422                 rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 423                     SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl),
 424                     OID_AUTO,
 425                     rs->rs_ifp->if_xname,
 426                     CTLFLAG_RW, 0,
 427                     "");
 428                 rl_add_syctl_entries(rl_sysctl_root, rs);
 429                 mtx_lock(&rs_mtx);
 430                 CK_LIST_INSERT_HEAD(&int_rs, rs, next);
 431                 mtx_unlock(&rs_mtx);
 432                 return (rs);
 433         } else if ((rl.flags & RT_IS_FIXED_TABLE) == RT_IS_FIXED_TABLE) {
 434                 /* Mellanox most likely */
 435                 rs->rs_ifp = ifp;
 436                 rs->rs_if_dunit = ifp->if_dunit;
 437                 rs->rs_rate_cnt = rl.number_of_rates;
 438                 rs->rs_min_seg = rl.min_segment_burst;
 439                 rs->rs_highest_valid = 0;
 440                 rs->rs_flow_limit = rl.max_flows;
 441                 rs->rs_flags = RS_IS_INTF | RS_NO_PRE;
 442                 rs->rs_disable = 0;
 443                 rate_table_act = rl.rate_table;
 444         } else if ((rl.flags & RT_IS_SELECTABLE) == RT_IS_SELECTABLE) {
 445                 /* Chelsio */
 446                 rs->rs_ifp = ifp;
 447                 rs->rs_if_dunit = ifp->if_dunit;
 448                 rs->rs_rate_cnt = rl.number_of_rates;
 449                 rs->rs_min_seg = rl.min_segment_burst;
 450                 rs->rs_disable = 0;
 451                 rs->rs_flow_limit = rl.max_flows;
 452                 rate_table_act = desired_rates;
 453                 if ((rs->rs_rate_cnt > MAX_HDWR_RATES) &&
 454                     (rs->rs_rate_cnt < ALL_HARDWARE_RATES)) {
 455                         /*
 456                          * Our desired table is not big
 457                          * enough, do what we can.
 458                          */
 459                         rs->rs_rate_cnt = MAX_HDWR_RATES;
 460                  }
 461                 if (rs->rs_rate_cnt <= RS_ORDERED_COUNT)
 462                         rs->rs_flags = RS_IS_INTF;
 463                 else
 464                         rs->rs_flags = RS_IS_INTF | RS_INT_TBL;
 465                 if (rs->rs_rate_cnt >= ALL_HARDWARE_RATES)
 466                         rs->rs_rate_cnt = ALL_HARDWARE_RATES;
 467         } else {
 468                 printf("Interface:%s unit:%d not one known to have rate-limits\n",
 469                     ifp->if_dname,
 470                     ifp->if_dunit);
 471                 free(rs, M_TCPPACE);
 472                 return (NULL);
 473         }
 474         sz = sizeof(struct tcp_hwrate_limit_table) * rs->rs_rate_cnt;
 475         rs->rs_rlt = malloc(sz, M_TCPPACE, M_NOWAIT);
 476         if (rs->rs_rlt == NULL) {
 477                 if (error)
 478                         *error = ENOMEM;
 479 bail:
 480                 free(rs, M_TCPPACE);
 481                 return (NULL);
 482         }
 483         if (rs->rs_rate_cnt >= ALL_HARDWARE_RATES) {
 484                 /*
 485                  * The interface supports all
 486                  * the rates we could possibly want.
 487                  */
 488                 uint64_t rat;
 489
 490                 rs->rs_rlt[0].rate = 12500;     /* 100k */
 491                 rs->rs_rlt[1].rate = 25000;     /* 200k */
 492                 rs->rs_rlt[2].rate = 62500;     /* 500k */
 493                 /* Note 125000 == 1Megabit
 494                  * populate 1Meg - 1000meg.
 495                  */
 496                 for(i = 3, rat = 125000; i< (ALL_HARDWARE_RATES-1); i++) {
 497                         rs->rs_rlt[i].rate = rat;
 498                         rat += 125000;
 499                 }
 500                 rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate = 1250000000;
 501         } else if (rs->rs_flags & RS_INT_TBL) {
 502                 /* We populate this in a special way */
 503                 populate_canned_table(rs, rate_table_act);
 504         } else {
 505                 /*
 506                  * Just copy in the rates from
 507                  * the table, it is in order.
 508                  */
 509                 for (i=0; i<rs->rs_rate_cnt; i++) {
 510                         rs->rs_rlt[i].rate = rate_table_act[i];
 511                         rs->rs_rlt[i].time_between = 0;
 512                         rs->rs_rlt[i].flags = 0;
 513                 }
 514         }
 515         for (i = (rs->rs_rate_cnt - 1); i >= 0; i--) {
 516                 /*
 517                  * We go backwards through the list so that if we can't get
 518                  * a rate and fail to init one, we have at least a chance of
 519                  * getting the highest one.
 520                  */
 521                 rs->rs_rlt[i].ptbl = rs;
 522                 rs->rs_rlt[i].tag = NULL;
 523                 /*
 524                  * Calculate the time between.
 525                  */
 526                 lentim = ETHERNET_SEGMENT_SIZE * USECS_IN_SECOND;
 527                 res = lentim / rs->rs_rlt[i].rate;
 528                 if (res > 0)
 529                         rs->rs_rlt[i].time_between = res;
 530                 else
 531                         rs->rs_rlt[i].time_between = 1;
 532                 if (rs->rs_flags & RS_NO_PRE) {
 533                         rs->rs_rlt[i].flags = HDWRPACE_INITED;
 534                         rs->rs_lowest_valid = i;
 535                 } else {
 536                         int err;
 537 #ifdef RSS
 538                         hash_type = M_HASHTYPE_RSS_TCP_IPV4;
 539 #else
 540                         hash_type = M_HASHTYPE_OPAQUE_HASH;
 541 #endif
 542                         err = rl_attach_txrtlmt(ifp,
 543                             hash_type,
 544                             (i + 1),
 545                             rs->rs_rlt[i].rate,
 546                             &rs->rs_rlt[i].tag);
 547                         if (err) {
 548                                 if (i == (rs->rs_rate_cnt - 1)) {
 549                                         /*
 550                                          * Huh - first rate and we can't get
 551                                          * it?
 552                                          */
 553                                         free(rs->rs_rlt, M_TCPPACE);
 554                                         if (error)
 555                                                 *error = err;
 556                                         goto bail;
 557                                 } else {
 558                                         if (error)
 559                                                 *error = err;
 560                                 }
 561                                 break;
 562                         } else {
 563                                 rs->rs_rlt[i].flags = HDWRPACE_INITED | HDWRPACE_TAGPRESENT;
 564                                 rs->rs_lowest_valid = i;
 565                         }
 566                 }
 567         }
 568         /* Did we get at least 1 rate? */
 569         if (rs->rs_rlt[(rs->rs_rate_cnt - 1)].flags & HDWRPACE_INITED)
 570                 rs->rs_highest_valid = rs->rs_rate_cnt - 1;
 571         else {
 572                 free(rs->rs_rlt, M_TCPPACE);
 573                 goto bail;
 574         }
 575         rs_number_alive++;
 576         sysctl_ctx_init(&rs->sysctl_ctx);
 577         rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 578             SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl),
 579             OID_AUTO,
 580             rs->rs_ifp->if_xname,
 581             CTLFLAG_RW, 0,
 582             "");
 583         rl_add_syctl_entries(rl_sysctl_root, rs);
 584         mtx_lock(&rs_mtx);
 585         CK_LIST_INSERT_HEAD(&int_rs, rs, next);
 586         mtx_unlock(&rs_mtx);
 587         return (rs);
 588 }
 589
 590 static const struct tcp_hwrate_limit_table *
 591 tcp_int_find_suitable_rate(const struct tcp_rate_set *rs,
 592     uint64_t bytes_per_sec, uint32_t flags)
 593 {
 594         struct tcp_hwrate_limit_table *arte = NULL, *rte = NULL;
 595         uint64_t mbits_per_sec, ind_calc;
 596         int i;
 597
 598         mbits_per_sec = (bytes_per_sec * 8);
 599         if (flags & RS_PACING_LT) {
 600                 if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) &&
 601                     (rs->rs_lowest_valid <= 2)){
 602                         /*
 603                          * Smaller than 1Meg, only
 604                          * 3 entries can match it.
 605                          */
 606                         for(i = rs->rs_lowest_valid; i < 3; i++) {
 607                                 if (bytes_per_sec <= rs->rs_rlt[i].rate) {
 608                                         rte = &rs->rs_rlt[i];
 609                                         break;
 610                                 } else if (rs->rs_rlt[i].flags & HDWRPACE_INITED) {
 611                                         arte = &rs->rs_rlt[i];
 612                                 }
 613                         }
 614                         goto done;
 615                 } else if ((mbits_per_sec > RS_ONE_GIGABIT_PERSEC) &&
 616                            (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)){
 617                         /*
 618                          * Larger than 1G (the majority of
 619                          * our table.
 620                          */
 621                         if (mbits_per_sec < RS_TEN_GIGABIT_PERSEC)
 622                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 623                         else
 624                                 arte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 625                         goto done;
 626                 }
 627                 /*
 628                  * If we reach here its in our table (between 1Meg - 1000Meg),
 629                  * just take the rounded down mbits per second, and add
 630                  * 1Megabit to it, from this we can calculate
 631                  * the index in the table.
 632                  */
 633                 ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC;
 634                 if ((ind_calc * RS_ONE_MEGABIT_PERSEC) != mbits_per_sec)
 635                         ind_calc++;
 636                 /* our table is offset by 3, we add 2 */
 637                 ind_calc += 2;
 638                 if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 639                         /* This should not happen */
 640                         ind_calc = ALL_HARDWARE_RATES-1;
 641                 }
 642                 if ((ind_calc >= rs->rs_lowest_valid) &&
 643                     (ind_calc <= rs->rs_highest_valid))
 644                 rte = &rs->rs_rlt[ind_calc];
 645         } else if (flags & RS_PACING_EXACT_MATCH) {
 646                 if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) &&
 647                     (rs->rs_lowest_valid <= 2)){
 648                         for(i = rs->rs_lowest_valid; i < 3; i++) {
 649                                 if (bytes_per_sec == rs->rs_rlt[i].rate) {
 650                                         rte = &rs->rs_rlt[i];
 651                                         break;
 652                                 }
 653                         }
 654                 } else if ((mbits_per_sec > RS_ONE_GIGABIT_PERSEC) &&
 655                            (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)) {
 656                         /* > 1Gbps only one rate */
 657                         if (bytes_per_sec == rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) {
 658                                 /* Its 10G wow */
 659                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 660                         }
 661                 } else {
 662                         /* Ok it must be a exact meg (its between 1G and 1Meg) */
 663                         ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC;
 664                         if ((ind_calc * RS_ONE_MEGABIT_PERSEC) == mbits_per_sec) {
 665                                 /* its an exact Mbps */
 666                                 ind_calc += 2;
 667                                 if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 668                                         /* This should not happen */
 669                                         ind_calc = ALL_HARDWARE_RATES-1;
 670                                 }
 671                                 if (rs->rs_rlt[ind_calc].flags & HDWRPACE_INITED)
 672                                         rte = &rs->rs_rlt[ind_calc];
 673                         }
 674                 }
 675         } else {
 676                 /* we want greater than the requested rate */
 677                 if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) &&
 678                     (rs->rs_lowest_valid <= 2)){
 679                         arte = &rs->rs_rlt[3]; /* set alternate to 1Meg */
 680                         for (i=2; i>=rs->rs_lowest_valid; i--) {
 681                                 if (bytes_per_sec < rs->rs_rlt[i].rate) {
 682                                         rte = &rs->rs_rlt[i];
 683                                         break;
 684                                 } else if ((flags & RS_PACING_GEQ) &&
 685                                            (bytes_per_sec == rs->rs_rlt[i].rate)) {
 686                                         rte = &rs->rs_rlt[i];
 687                                         break;
 688                                 } else {
 689                                         arte = &rs->rs_rlt[i]; /* new alternate */
 690                                 }
 691                         }
 692                 } else if (mbits_per_sec > RS_ONE_GIGABIT_PERSEC) {
 693                         if ((bytes_per_sec < rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) &&
 694                             (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)){
 695                                 /* Our top rate is larger than the request */
 696                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 697                         } else if ((flags & RS_PACING_GEQ) &&
 698                                    (bytes_per_sec == rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) &&
 699                                    (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)) {
 700                                 /* It matches our top rate */
 701                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 702                         } else if (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED) {
 703                                 /* The top rate is an alternative */
 704                                 arte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 705                         }
 706                 } else {
 707                         /* Its in our range 1Meg - 1Gig */
 708                         if (flags & RS_PACING_GEQ) {
 709                                 ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC;
 710                                 if ((ind_calc * RS_ONE_MEGABIT_PERSEC) == mbits_per_sec) {
 711                                         if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 712                                                 /* This should not happen */
 713                                                 ind_calc = (ALL_HARDWARE_RATES-1);
 714                                         }
 715                                         rte = &rs->rs_rlt[ind_calc];
 716                                 }
 717                                 goto done;
 718                         }
 719                         ind_calc = (mbits_per_sec + (RS_ONE_MEGABIT_PERSEC-1))/RS_ONE_MEGABIT_PERSEC;
 720                         ind_calc += 2;
 721                         if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 722                                 /* This should not happen */
 723                                 ind_calc = ALL_HARDWARE_RATES-1;
 724                         }
 725                         if (rs->rs_rlt[ind_calc].flags & HDWRPACE_INITED)
 726                                 rte = &rs->rs_rlt[ind_calc];
 727                 }
 728         }
 729 done:
 730         if ((rte == NULL) &&
 731             (arte != NULL) &&
 732             (flags & RS_PACING_SUB_OK)) {
 733                 /* We can use the substitute */
 734                 rte = arte;
 735         }
 736         return (rte);
 737 }
 738
 739 static const struct tcp_hwrate_limit_table *
 740 tcp_find_suitable_rate(const struct tcp_rate_set *rs, uint64_t bytes_per_sec, uint32_t flags)
 741 {
 742         /**
 743          * Hunt the rate table with the restrictions in flags and find a
 744          * suitable rate if possible.
 745          * RS_PACING_EXACT_MATCH - look for an exact match to rate.
 746          * RS_PACING_GT     - must be greater than.
 747          * RS_PACING_GEQ    - must be greater than or equal.
 748          * RS_PACING_LT     - must be less than.
 749          * RS_PACING_SUB_OK - If we don't meet criteria a
 750          *                    substitute is ok.
 751          */
 752         int i, matched;
 753         struct tcp_hwrate_limit_table *rte = NULL;
 754
 755
 756         if ((rs->rs_flags & RS_INT_TBL) &&
 757             (rs->rs_rate_cnt >= ALL_HARDWARE_RATES)) {
 758                 /*
 759                  * Here we don't want to paw thru
 760                  * a big table, we have everything
 761                  * from 1Meg - 1000Meg in 1Meg increments.
 762                  * Use an alternate method to "lookup".
 763                  */
 764                 return (tcp_int_find_suitable_rate(rs, bytes_per_sec, flags));
 765         }
 766         if ((flags & RS_PACING_LT) ||
 767             (flags & RS_PACING_EXACT_MATCH)) {
 768                 /*
 769                  * For exact and less than we go forward through the table.
 770                  * This way when we find one larger we stop (exact was a
 771                  * toss up).
 772                  */
 773                 for (i = rs->rs_lowest_valid, matched = 0; i <= rs->rs_highest_valid; i++) {
 774                         if ((flags & RS_PACING_EXACT_MATCH) &&
 775                             (bytes_per_sec == rs->rs_rlt[i].rate)) {
 776                                 rte = &rs->rs_rlt[i];
 777                                 matched = 1;
 778                                 break;
 779                         } else if ((flags & RS_PACING_LT) &&
 780                             (bytes_per_sec <= rs->rs_rlt[i].rate)) {
 781                                 rte = &rs->rs_rlt[i];
 782                                 matched = 1;
 783                                 break;
 784                         }
 785                         if (bytes_per_sec > rs->rs_rlt[i].rate)
 786                                 break;
 787                 }
 788                 if ((matched == 0) &&
 789                     (flags & RS_PACING_LT) &&
 790                     (flags & RS_PACING_SUB_OK)) {
 791                         /* Kick in a substitute (the lowest) */
 792                         rte = &rs->rs_rlt[rs->rs_lowest_valid];
 793                 }
 794         } else {
 795                 /*
 796                  * Here we go backward through the table so that we can find
 797                  * the one greater in theory faster (but its probably a
 798                  * wash).
 799                  */
 800                 for (i = rs->rs_highest_valid, matched = 0; i >= rs->rs_lowest_valid; i--) {
 801                         if (rs->rs_rlt[i].rate > bytes_per_sec) {
 802                                 /* A possible candidate */
 803                                 rte = &rs->rs_rlt[i];
 804                         }
 805                         if ((flags & RS_PACING_GEQ) &&
 806                             (bytes_per_sec == rs->rs_rlt[i].rate)) {
 807                                 /* An exact match and we want equal */
 808                                 matched = 1;
 809                                 rte = &rs->rs_rlt[i];
 810                                 break;
 811                         } else if (rte) {
 812                                 /*
 813                                  * Found one that is larger than but don't
 814                                  * stop, there may be a more closer match.
 815                                  */
 816                                 matched = 1;
 817                         }
 818                         if (rs->rs_rlt[i].rate < bytes_per_sec) {
 819                                 /*
 820                                  * We found a table entry that is smaller,
 821                                  * stop there will be none greater or equal.
 822                                  */
 823                                 break;
 824                         }
 825                 }
 826                 if ((matched == 0) &&
 827                     (flags & RS_PACING_SUB_OK)) {
 828                         /* Kick in a substitute (the highest) */
 829                         rte = &rs->rs_rlt[rs->rs_highest_valid];
 830                 }
 831         }
 832         return (rte);
 833 }
 834
 835 static struct ifnet *
 836 rt_find_real_interface(struct ifnet *ifp, struct inpcb *inp, int *error)
 837 {
 838         struct ifnet *tifp;
 839         struct m_snd_tag *tag;
 840         union if_snd_tag_alloc_params params = {
 841                 .rate_limit.hdr.type = IF_SND_TAG_TYPE_RATE_LIMIT,
 842                 .rate_limit.hdr.flowid = 1,
 843                 .rate_limit.max_rate = COMMON_RATE,
 844                 .rate_limit.flags = M_NOWAIT,
 845         };
 846         int err;
 847 #ifdef RSS
 848         params.rate_limit.hdr.flowtype = ((inp->inp_vflag & INP_IPV6) ?
 849             M_HASHTYPE_RSS_TCP_IPV6 : M_HASHTYPE_RSS_TCP_IPV4);
 850 #else
 851         params.rate_limit.hdr.flowtype = M_HASHTYPE_OPAQUE_HASH;
 852 #endif
 853         tag = NULL;
 854         if (ifp->if_snd_tag_alloc) {
 855                 if (error)
 856                         *error = ENODEV;
 857                 return (NULL);
 858         }
 859         err = ifp->if_snd_tag_alloc(ifp, &params, &tag);
 860         if (err) {
 861                 /* Failed to setup a tag? */
 862                 if (error)
 863                         *error = err;
 864                 return (NULL);
 865         }
 866         tifp = tag->ifp;
 867         tifp->if_snd_tag_free(tag);
 868         return (tifp);
 869 }
 870
 871 static const struct tcp_hwrate_limit_table *
 872 rt_setup_rate(struct inpcb *inp, struct ifnet *ifp, uint64_t bytes_per_sec,
 873     uint32_t flags, int *error)
 874 {
 875         /* First lets find the interface if it exists */
 876         const struct tcp_hwrate_limit_table *rte;
 877         struct tcp_rate_set *rs;
 878         struct epoch_tracker et;
 879         int err;
 880
 881         epoch_enter_preempt(net_epoch_preempt, &et);
 882 use_real_interface:
 883         CK_LIST_FOREACH(rs, &int_rs, next) {
 884                 /*
 885                  * Note we don't look with the lock since we either see a
 886                  * new entry or will get one when we try to add it.
 887                  */
 888                 if (rs->rs_flags & RS_IS_DEAD) {
 889                         /* The dead are not looked at */
 890                         continue;
 891                 }
 892                 if ((rs->rs_ifp == ifp) &&
 893                     (rs->rs_if_dunit == ifp->if_dunit)) {
 894                         /* Ok we found it */
 895                         break;
 896                 }
 897         }
 898         if ((rs == NULL) ||
 899             (rs->rs_flags & RS_INTF_NO_SUP) ||
 900             (rs->rs_flags & RS_IS_DEAD)) {
 901                 /*
 902                  * This means we got a packet *before*
 903                  * the IF-UP was processed below, <or>
 904                  * while or after we already received an interface
 905                  * departed event. In either case we really don't
 906                  * want to do anything with pacing, in
 907                  * the departing case the packet is not
 908                  * going to go very far. The new case
 909                  * might be arguable, but its impossible
 910                  * to tell from the departing case.
 911                  */
 912                 if (rs->rs_disable && error)
 913                         *error = ENODEV;
 914                 epoch_exit_preempt(net_epoch_preempt, &et);
 915                 return (NULL);
 916         }
 917
 918         if ((rs == NULL) || (rs->rs_disable != 0)) {
 919                 if (rs->rs_disable && error)
 920                         *error = ENOSPC;
 921                 epoch_exit_preempt(net_epoch_preempt, &et);
 922                 return (NULL);
 923         }
 924         if (rs->rs_flags & RS_IS_DEFF) {
 925                 /* We need to find the real interface */
 926                 struct ifnet *tifp;
 927
 928                 tifp = rt_find_real_interface(ifp, inp, error);
 929                 if (tifp == NULL) {
 930                         if (rs->rs_disable && error)
 931                                 *error = ENOTSUP;
 932                         epoch_exit_preempt(net_epoch_preempt, &et);
 933                         return (NULL);
 934                 }
 935                 goto use_real_interface;
 936         }
 937         if (rs->rs_flow_limit &&
 938             ((rs->rs_flows_using + 1) > rs->rs_flow_limit)) {
 939                 if (error)
 940                         *error = ENOSPC;
 941                 epoch_exit_preempt(net_epoch_preempt, &et);
 942                 return (NULL);
 943         }
 944         rte = tcp_find_suitable_rate(rs, bytes_per_sec, flags);
 945         if (rte) {
 946                 err = in_pcbattach_txrtlmt(inp, rs->rs_ifp,
 947                     inp->inp_flowtype,
 948                     inp->inp_flowid,
 949                     rte->rate,
 950                     &inp->inp_snd_tag);
 951                 if (err) {
 952                         /* Failed to attach */
 953                         if (error)
 954                                 *error = err;
 955                         rte = NULL;
 956                 }
 957         }
 958         if (rte) {
 959                 /*
 960                  * We use an atomic here for accounting so we don't have to
 961                  * use locks when freeing.
 962                  */
 963                 atomic_add_64(&rs->rs_flows_using, 1);
 964         }
 965         epoch_exit_preempt(net_epoch_preempt, &et);
 966         return (rte);
 967 }
 968
 969 static void
 970 tcp_rl_ifnet_link(void *arg __unused, struct ifnet *ifp, int link_state)
 971 {
 972         int error;
 973         struct tcp_rate_set *rs;
 974
 975         if (((ifp->if_capabilities & IFCAP_TXRTLMT) == 0) ||
 976             (link_state != LINK_STATE_UP)) {
 977                 /*
 978                  * We only care on an interface going up that is rate-limit
 979                  * capable.
 980                  */
 981                 return;
 982         }
 983         mtx_lock(&rs_mtx);
 984         CK_LIST_FOREACH(rs, &int_rs, next) {
 985                 if ((rs->rs_ifp == ifp) &&
 986                     (rs->rs_if_dunit == ifp->if_dunit)) {
 987                         /* We already have initialized this guy */
 988                         mtx_unlock(&rs_mtx);
 989                         return;
 990                 }
 991         }
 992         mtx_unlock(&rs_mtx);
 993         rt_setup_new_rs(ifp, &error);
 994 }
 995
 996 static void
 997 tcp_rl_ifnet_departure(void *arg __unused, struct ifnet *ifp)
 998 {
 999         struct tcp_rate_set *rs, *nrs;
1000         struct ifnet *tifp;
1001         int i;
1002
1003         mtx_lock(&rs_mtx);
1004         CK_LIST_FOREACH_SAFE(rs, &int_rs, next, nrs) {
1005                 if ((rs->rs_ifp == ifp) &&
1006                     (rs->rs_if_dunit == ifp->if_dunit)) {
1007                         CK_LIST_REMOVE(rs, next);
1008                         rs_number_alive--;
1009                         rs->rs_flags |= RS_IS_DEAD;
1010                         for (i = 0; i < rs->rs_rate_cnt; i++) {
1011                                 if (rs->rs_rlt[i].flags & HDWRPACE_TAGPRESENT) {
1012                                         tifp = rs->rs_rlt[i].tag->ifp;
1013                                         in_pcbdetach_tag(tifp, rs->rs_rlt[i].tag);
1014                                         rs->rs_rlt[i].tag = NULL;
1015                                 }
1016                                 rs->rs_rlt[i].flags = HDWRPACE_IFPDEPARTED;
1017                         }
1018                         if (rs->rs_flows_using == 0)
1019                                 rs_defer_destroy(rs);
1020                         break;
1021                 }
1022         }
1023         mtx_unlock(&rs_mtx);
1024 }
1025
1026 static void
1027 tcp_rl_shutdown(void *arg __unused, int howto __unused)
1028 {
1029         struct tcp_rate_set *rs, *nrs;
1030         struct ifnet *tifp;
1031         int i;
1032
1033         mtx_lock(&rs_mtx);
1034         CK_LIST_FOREACH_SAFE(rs, &int_rs, next, nrs) {
1035                 CK_LIST_REMOVE(rs, next);
1036                 rs_number_alive--;
1037                 rs->rs_flags |= RS_IS_DEAD;
1038                 for (i = 0; i < rs->rs_rate_cnt; i++) {
1039                         if (rs->rs_rlt[i].flags & HDWRPACE_TAGPRESENT) {
1040                                 tifp = rs->rs_rlt[i].tag->ifp;
1041                                 in_pcbdetach_tag(tifp, rs->rs_rlt[i].tag);
1042                                 rs->rs_rlt[i].tag = NULL;
1043                         }
1044                         rs->rs_rlt[i].flags = HDWRPACE_IFPDEPARTED;
1045                 }
1046                 if (rs->rs_flows_using == 0)
1047                         rs_defer_destroy(rs);
1048         }
1049         mtx_unlock(&rs_mtx);
1050 }
1051
1052 const struct tcp_hwrate_limit_table *
1053 tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp,
1054     uint64_t bytes_per_sec, int flags, int *error)
1055 {
1056         const struct tcp_hwrate_limit_table *rte;
1057
1058         if (tp->t_inpcb->inp_snd_tag == NULL) {
1059                 /*
1060                  * We are setting up a rate for the first time.
1061                  */
1062                 if ((ifp->if_capabilities & IFCAP_TXRTLMT) == 0) {
1063                         /* Not supported by the egress */
1064                         if (error)
1065                                 *error = ENODEV;
1066                         return (NULL);
1067                 }
1068 #ifdef KERN_TLS
1069                 if (tp->t_inpcb->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) {
1070                         /*
1071                          * We currently can't do both TLS and hardware
1072                          * pacing
1073                          */
1074                         if (error)
1075                                 *error = EINVAL;
1076                         return (NULL);
1077                 }
1078 #endif
1079                 rte = rt_setup_rate(tp->t_inpcb, ifp, bytes_per_sec, flags, error);
1080         } else {
1081                 /*
1082                  * We are modifying a rate, wrong interface?
1083                  */
1084                 if (error)
1085                         *error = EINVAL;
1086                 rte = NULL;
1087         }
1088         return (rte);
1089 }
1090
1091 const struct tcp_hwrate_limit_table *
1092 tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte,
1093     struct tcpcb *tp, struct ifnet *ifp,
1094     uint64_t bytes_per_sec, int flags, int *error)
1095 {
1096         const struct tcp_hwrate_limit_table *nrte;
1097         const struct tcp_rate_set *rs;
1098         int is_indirect = 0;
1099         int err;
1100
1101
1102         if ((tp->t_inpcb->inp_snd_tag == NULL) ||
1103             (crte == NULL)) {
1104                 /* Wrong interface */
1105                 if (error)
1106                         *error = EINVAL;
1107                 return (NULL);
1108         }
1109         rs = crte->ptbl;
1110         if ((rs->rs_flags & RS_IS_DEAD) ||
1111             (crte->flags & HDWRPACE_IFPDEPARTED)) {
1112                 /* Release the rate, and try anew */
1113 re_rate:
1114                 tcp_rel_pacing_rate(crte, tp);
1115                 nrte = tcp_set_pacing_rate(tp, ifp,
1116                     bytes_per_sec, flags, error);
1117                 return (nrte);
1118         }
1119         if ((rs->rs_flags & RT_IS_INDIRECT ) == RT_IS_INDIRECT)
1120                 is_indirect = 1;
1121         else
1122                 is_indirect = 0;
1123         if ((is_indirect == 0) &&
1124             ((ifp != rs->rs_ifp) ||
1125             (ifp->if_dunit != rs->rs_if_dunit))) {
1126                 /*
1127                  * Something changed, the user is not pointing to the same
1128                  * ifp? Maybe a route updated on this guy?
1129                  */
1130                 goto re_rate;
1131         } else if (is_indirect) {
1132                 /*
1133                  * For indirect we have to dig in and find the real interface.
1134                  */
1135                 struct ifnet *rifp;
1136
1137                 rifp = rt_find_real_interface(ifp, tp->t_inpcb, error);
1138                 if (rifp == NULL) {
1139                         /* Can't find it? */
1140                         goto re_rate;
1141                 }
1142                 if ((rifp != rs->rs_ifp) ||
1143                     (ifp->if_dunit != rs->rs_if_dunit)) {
1144                         goto re_rate;
1145                 }
1146         }
1147         nrte = tcp_find_suitable_rate(rs, bytes_per_sec, flags);
1148         if (nrte == crte) {
1149                 /* No change */
1150                 if (error)
1151                         *error = 0;
1152                 return (crte);
1153         }
1154         if (nrte == NULL) {
1155                 /* Release the old rate */
1156                 tcp_rel_pacing_rate(crte, tp);
1157                 return (NULL);
1158         }
1159         /* Change rates to our new entry */
1160         err = in_pcbmodify_txrtlmt(tp->t_inpcb, nrte->rate);
1161         if (err) {
1162                 if (error)
1163                         *error = err;
1164                 return (NULL);
1165         }
1166         if (error)
1167                 *error = 0;
1168         return (nrte);
1169 }
1170
1171 void
1172 tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, struct tcpcb *tp)
1173 {
1174         const struct tcp_rate_set *crs;
1175         struct tcp_rate_set *rs;
1176         uint64_t pre;
1177
1178         crs = crte->ptbl;
1179         /*
1180          * Now we must break the const
1181          * in order to release our refcount.
1182          */
1183         rs = __DECONST(struct tcp_rate_set *, crs);
1184         pre = atomic_fetchadd_64(&rs->rs_flows_using, -1);
1185         if (pre == 1) {
1186                 mtx_lock(&rs_mtx);
1187                 /*
1188                  * Is it dead?
1189                  */
1190                 if (rs->rs_flags & RS_IS_DEAD)
1191                         rs_defer_destroy(rs);
1192                 mtx_unlock(&rs_mtx);
1193         }
1194         in_pcbdetach_txrtlmt(tp->t_inpcb);
1195 }
1196
1197 static eventhandler_tag rl_ifnet_departs;
1198 static eventhandler_tag rl_ifnet_arrives;
1199 static eventhandler_tag rl_shutdown_start;
1200
1201 static void
1202 tcp_rs_init(void *st __unused)
1203 {
1204         CK_LIST_INIT(&int_rs);
1205         rs_number_alive = 0;
1206         rs_number_dead = 0;;
1207         mtx_init(&rs_mtx, "tcp_rs_mtx", "rsmtx", MTX_DEF);
1208         rl_ifnet_departs = EVENTHANDLER_REGISTER(ifnet_departure_event,
1209             tcp_rl_ifnet_departure,
1210             NULL, EVENTHANDLER_PRI_ANY);
1211         rl_ifnet_arrives = EVENTHANDLER_REGISTER(ifnet_link_event,
1212             tcp_rl_ifnet_link,
1213             NULL, EVENTHANDLER_PRI_ANY);
1214         rl_shutdown_start = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1215             tcp_rl_shutdown, NULL,
1216             SHUTDOWN_PRI_FIRST);
1217         printf("TCP_ratelimit: Is now initialized\n");
1218 }
1219
1220 SYSINIT(tcp_rl_init, SI_SUB_SMP + 1, SI_ORDER_ANY, tcp_rs_init, NULL);
1221 #endif