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 #include <net/if.h>
  53 #include <net/if_var.h>
  54 #include <netinet/in.h>
  55 #include <netinet/in_pcb.h>
  56 #define TCPSTATES               /* for logging */
  57 #include <netinet/tcp_var.h>
  58 #ifdef INET6
  59 #include <netinet6/tcp6_var.h>
  60 #endif
  61 #include <netinet/tcp_ratelimit.h>
  62 #ifndef USECS_IN_SECOND
  63 #define USECS_IN_SECOND 1000000
  64 #endif
  65 /*
  66  * For the purposes of each send, what is the size
  67  * of an ethernet frame.
  68  */
  69 #ifndef ETHERNET_SEGMENT_SIZE
  70 #define ETHERNET_SEGMENT_SIZE 1500
  71 #endif
  72 MALLOC_DEFINE(M_TCPPACE, "tcp_hwpace", "TCP Hardware pacing memory");
  73 #ifdef RATELIMIT
  74
  75 #define COMMON_RATE 180500
  76 uint64_t desired_rates[] = {
  77         62500,                  /* 500Kbps */
  78         180500,                 /* 1.44Mpbs */
  79         375000,                 /* 3Mbps */
  80         500000,                 /* 4Mbps */
  81         625000,                 /* 5Mbps */
  82         750000,                 /* 6Mbps */
  83         1000000,                /* 8Mbps */
  84         1250000,                /* 10Mbps */
  85         2500000,                /* 20Mbps */
  86         3750000,                /* 30Mbps */
  87         5000000,                /* 40Meg */
  88         6250000,                /* 50Mbps */
  89         12500000,               /* 100Mbps */
  90         25000000,               /* 200Mbps */
  91         50000000,               /* 400Mbps */
  92         100000000,              /* 800Mbps */
  93         12500,                  /* 100kbps */
  94         25000,                  /* 200kbps */
  95         875000,                 /* 7Mbps */
  96         1125000,                /* 9Mbps */
  97         1875000,                /* 15Mbps */
  98         3125000,                /* 25Mbps */
  99         8125000,                /* 65Mbps */
 100         10000000,               /* 80Mbps */
 101         18750000,               /* 150Mbps */
 102         20000000,               /* 250Mbps */
 103         37500000,               /* 350Mbps */
 104         62500000,               /* 500Mbps */
 105         78125000,               /* 625Mbps */
 106         125000000,              /* 1Gbps */
 107 };
 108 #define MAX_HDWR_RATES (sizeof(desired_rates)/sizeof(uint64_t))
 109 #define RS_ORDERED_COUNT 16     /*
 110                                  * Number that are in order
 111                                  * at the beginning of the table,
 112                                  * over this a sort is required.
 113                                  */
 114 #define RS_NEXT_ORDER_GROUP 16  /*
 115                                  * The point in our table where
 116                                  * we come fill in a second ordered
 117                                  * group (index wise means -1).
 118                                  */
 119 #define ALL_HARDWARE_RATES 1004 /*
 120                                  * 1Meg - 1Gig in 1 Meg steps
 121                                  * plus 100, 200k  and 500k and
 122                                  * 10Gig
 123                                  */
 124
 125 #define RS_ONE_MEGABIT_PERSEC 1000000
 126 #define RS_ONE_GIGABIT_PERSEC 1000000000
 127 #define RS_TEN_GIGABIT_PERSEC 10000000000
 128
 129 static struct head_tcp_rate_set int_rs;
 130 static struct mtx rs_mtx;
 131 uint32_t rs_number_alive;
 132 uint32_t rs_number_dead;
 133
 134 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, rl, CTLFLAG_RW, 0,
 135     "TCP Ratelimit stats");
 136 SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, alive, CTLFLAG_RW,
 137     &rs_number_alive, 0,
 138     "Number of interfaces initialized for ratelimiting");
 139 SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, dead, CTLFLAG_RW,
 140     &rs_number_dead, 0,
 141     "Number of interfaces departing from ratelimiting");
 142
 143 static void
 144 rl_add_syctl_entries(struct sysctl_oid *rl_sysctl_root, struct tcp_rate_set *rs)
 145 {
 146         /*
 147          * Add sysctl entries for thus interface.
 148          */
 149         if (rs->rs_flags & RS_INTF_NO_SUP) {
 150                 SYSCTL_ADD_S32(&rs->sysctl_ctx,
 151                    SYSCTL_CHILDREN(rl_sysctl_root),
 152                    OID_AUTO, "disable", CTLFLAG_RD,
 153                    &rs->rs_disable, 0,
 154                    "Disable this interface from new hdwr limiting?");
 155         } else {
 156                 SYSCTL_ADD_S32(&rs->sysctl_ctx,
 157                    SYSCTL_CHILDREN(rl_sysctl_root),
 158                    OID_AUTO, "disable", CTLFLAG_RW,
 159                    &rs->rs_disable, 0,
 160                    "Disable this interface from new hdwr limiting?");
 161         }
 162         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 163             SYSCTL_CHILDREN(rl_sysctl_root),
 164             OID_AUTO, "minseg", CTLFLAG_RW,
 165             &rs->rs_min_seg, 0,
 166             "What is the minimum we need to send on this interface?");
 167         SYSCTL_ADD_U64(&rs->sysctl_ctx,
 168             SYSCTL_CHILDREN(rl_sysctl_root),
 169             OID_AUTO, "flow_limit", CTLFLAG_RW,
 170             &rs->rs_flow_limit, 0,
 171             "What is the limit for number of flows (0=unlimited)?");
 172         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 173             SYSCTL_CHILDREN(rl_sysctl_root),
 174             OID_AUTO, "highest", CTLFLAG_RD,
 175             &rs->rs_highest_valid, 0,
 176             "Highest valid rate");
 177         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 178             SYSCTL_CHILDREN(rl_sysctl_root),
 179             OID_AUTO, "lowest", CTLFLAG_RD,
 180             &rs->rs_lowest_valid, 0,
 181             "Lowest valid rate");
 182         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 183             SYSCTL_CHILDREN(rl_sysctl_root),
 184             OID_AUTO, "flags", CTLFLAG_RD,
 185             &rs->rs_flags, 0,
 186             "What lags are on the entry?");
 187         SYSCTL_ADD_S32(&rs->sysctl_ctx,
 188             SYSCTL_CHILDREN(rl_sysctl_root),
 189             OID_AUTO, "numrates", CTLFLAG_RD,
 190             &rs->rs_rate_cnt, 0,
 191             "How many rates re there?");
 192         SYSCTL_ADD_U64(&rs->sysctl_ctx,
 193             SYSCTL_CHILDREN(rl_sysctl_root),
 194             OID_AUTO, "flows_using", CTLFLAG_RD,
 195             &rs->rs_flows_using, 0,
 196             "How many flows are using this interface now?");
 197 #ifdef DETAILED_RATELIMIT_SYSCTL
 198         if (rs->rs_rlt && rs->rs_rate_cnt > 0) {
 199                 /*  Lets display the rates */
 200                 int i;
 201                 struct sysctl_oid *rl_rates;
 202                 struct sysctl_oid *rl_rate_num;
 203                 char rate_num[16];
 204                 rl_rates = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 205                                             SYSCTL_CHILDREN(rl_sysctl_root),
 206                                             OID_AUTO,
 207                                             "rate",
 208                                             CTLFLAG_RW, 0,
 209                                             "Ratelist");
 210                 for( i = 0; i < rs->rs_rate_cnt; i++) {
 211                         sprintf(rate_num, "%d", i);
 212                         rl_rate_num = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 213                                             SYSCTL_CHILDREN(rl_rates),
 214                                             OID_AUTO,
 215                                             rate_num,
 216                                             CTLFLAG_RW, 0,
 217                                             "Individual Rate");
 218                         SYSCTL_ADD_U32(&rs->sysctl_ctx,
 219                                        SYSCTL_CHILDREN(rl_rate_num),
 220                                        OID_AUTO, "flags", CTLFLAG_RD,
 221                                        &rs->rs_rlt[i].flags, 0,
 222                                        "Flags on this rate");
 223                         SYSCTL_ADD_U32(&rs->sysctl_ctx,
 224                                        SYSCTL_CHILDREN(rl_rate_num),
 225                                        OID_AUTO, "pacetime", CTLFLAG_RD,
 226                                        &rs->rs_rlt[i].time_between, 0,
 227                                        "Time hardware inserts between 1500 byte sends");
 228                         SYSCTL_ADD_U64(&rs->sysctl_ctx,
 229                                        SYSCTL_CHILDREN(rl_rate_num),
 230                                        OID_AUTO, "rate", CTLFLAG_RD,
 231                                        &rs->rs_rlt[i].rate, 0,
 232                                        "Rate in bytes per second");
 233                 }
 234         }
 235 #endif
 236 }
 237
 238 static void
 239 rs_destroy(epoch_context_t ctx)
 240 {
 241         struct tcp_rate_set *rs;
 242         bool do_free_rs;
 243
 244         rs = __containerof(ctx, struct tcp_rate_set, rs_epoch_ctx);
 245
 246         mtx_lock(&rs_mtx);
 247         rs->rs_flags &= ~RS_FUNERAL_SCHD;
 248         /*
 249          * In theory its possible (but unlikely)
 250          * that while the delete was occuring
 251          * and we were applying the DEAD flag
 252          * someone slipped in and found the
 253          * interface in a lookup. While we
 254          * decided rs_flows_using were 0 and
 255          * scheduling the epoch_call, the other
 256          * thread incremented rs_flow_using. This
 257          * is because users have a pointer and
 258          * we only use the rs_flows_using in an
 259          * atomic fashion, i.e. the other entities
 260          * are not protected. To assure this did
 261          * not occur, we check rs_flows_using here
 262          * before deleting.
 263          */
 264         do_free_rs = (rs->rs_flows_using == 0);
 265         rs_number_dead--;
 266         mtx_unlock(&rs_mtx);
 267
 268         if (do_free_rs) {
 269                 sysctl_ctx_free(&rs->sysctl_ctx);
 270                 free(rs->rs_rlt, M_TCPPACE);
 271                 free(rs, M_TCPPACE);
 272         }
 273 }
 274
 275 static void
 276 rs_defer_destroy(struct tcp_rate_set *rs)
 277 {
 278
 279         mtx_assert(&rs_mtx, MA_OWNED);
 280
 281         /* Check if already pending. */
 282         if (rs->rs_flags & RS_FUNERAL_SCHD)
 283                 return;
 284
 285         rs_number_dead++;
 286
 287         /* Set flag to only defer once. */
 288         rs->rs_flags |= RS_FUNERAL_SCHD;
 289         NET_EPOCH_CALL(rs_destroy, &rs->rs_epoch_ctx);
 290 }
 291
 292 #ifdef INET
 293 extern counter_u64_t rate_limit_set_ok;
 294 extern counter_u64_t rate_limit_active;
 295 extern counter_u64_t rate_limit_alloc_fail;
 296 #endif
 297
 298 static int
 299 rl_attach_txrtlmt(struct ifnet *ifp,
 300     uint32_t flowtype,
 301     int flowid,
 302     uint64_t cfg_rate,
 303     struct m_snd_tag **tag)
 304 {
 305         int error;
 306         union if_snd_tag_alloc_params params = {
 307                 .rate_limit.hdr.type = IF_SND_TAG_TYPE_RATE_LIMIT,
 308                 .rate_limit.hdr.flowid = flowid,
 309                 .rate_limit.hdr.flowtype = flowtype,
 310                 .rate_limit.max_rate = cfg_rate,
 311                 .rate_limit.flags = M_NOWAIT,
 312         };
 313
 314         if (ifp->if_snd_tag_alloc == NULL) {
 315                 error = EOPNOTSUPP;
 316         } else {
 317                 error = ifp->if_snd_tag_alloc(ifp, &params, tag);
 318 #ifdef INET
 319                 if (error == 0) {
 320                         if_ref((*tag)->ifp);
 321                         counter_u64_add(rate_limit_set_ok, 1);
 322                         counter_u64_add(rate_limit_active, 1);
 323                 } else
 324                         counter_u64_add(rate_limit_alloc_fail, 1);
 325 #endif
 326         }
 327         return (error);
 328 }
 329
 330 static void
 331 populate_canned_table(struct tcp_rate_set *rs, const uint64_t *rate_table_act)
 332 {
 333         /*
 334          * The internal table is "special", it
 335          * is two seperate ordered tables that
 336          * must be merged. We get here when the
 337          * adapter specifies a number of rates that
 338          * covers both ranges in the table in some
 339          * form.
 340          */
 341         int i, at_low, at_high;
 342         uint8_t low_disabled = 0, high_disabled = 0;
 343
 344         for(i = 0, at_low = 0, at_high = RS_NEXT_ORDER_GROUP; i < rs->rs_rate_cnt; i++) {
 345                 rs->rs_rlt[i].flags = 0;
 346                 rs->rs_rlt[i].time_between = 0;
 347                 if ((low_disabled == 0) &&
 348                     (high_disabled ||
 349                      (rate_table_act[at_low] < rate_table_act[at_high]))) {
 350                         rs->rs_rlt[i].rate = rate_table_act[at_low];
 351                         at_low++;
 352                         if (at_low == RS_NEXT_ORDER_GROUP)
 353                                 low_disabled = 1;
 354                 } else if (high_disabled == 0) {
 355                         rs->rs_rlt[i].rate = rate_table_act[at_high];
 356                         at_high++;
 357                         if (at_high == MAX_HDWR_RATES)
 358                                 high_disabled = 1;
 359                 }
 360         }
 361 }
 362
 363 static struct tcp_rate_set *
 364 rt_setup_new_rs(struct ifnet *ifp, int *error)
 365 {
 366         struct tcp_rate_set *rs;
 367         const uint64_t *rate_table_act;
 368         uint64_t lentim, res;
 369         size_t sz;
 370         uint32_t hash_type;
 371         int i;
 372         struct if_ratelimit_query_results rl;
 373         struct sysctl_oid *rl_sysctl_root;
 374         /*
 375          * We expect to enter with the
 376          * mutex locked.
 377          */
 378
 379         if (ifp->if_ratelimit_query == NULL) {
 380                 /*
 381                  * We can do nothing if we cannot
 382                  * get a query back from the driver.
 383                  */
 384                 return (NULL);
 385         }
 386         rs = malloc(sizeof(struct tcp_rate_set), M_TCPPACE, M_NOWAIT | M_ZERO);
 387         if (rs == NULL) {
 388                 if (error)
 389                         *error = ENOMEM;
 390                 return (NULL);
 391         }
 392         rl.flags = RT_NOSUPPORT;
 393         ifp->if_ratelimit_query(ifp, &rl);
 394         if (rl.flags & RT_IS_UNUSABLE) {
 395                 /*
 396                  * The interface does not really support
 397                  * the rate-limiting.
 398                  */
 399                 memset(rs, 0, sizeof(struct tcp_rate_set));
 400                 rs->rs_ifp = ifp;
 401                 rs->rs_if_dunit = ifp->if_dunit;
 402                 rs->rs_flags = RS_INTF_NO_SUP;
 403                 rs->rs_disable = 1;
 404                 rs_number_alive++;
 405                 sysctl_ctx_init(&rs->sysctl_ctx);
 406                 rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 407                     SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl),
 408                     OID_AUTO,
 409                     rs->rs_ifp->if_xname,
 410                     CTLFLAG_RW, 0,
 411                     "");
 412                 rl_add_syctl_entries(rl_sysctl_root, rs);
 413                 mtx_lock(&rs_mtx);
 414                 CK_LIST_INSERT_HEAD(&int_rs, rs, next);
 415                 mtx_unlock(&rs_mtx);
 416                 return (rs);
 417         } else if ((rl.flags & RT_IS_INDIRECT) == RT_IS_INDIRECT) {
 418                 memset(rs, 0, sizeof(struct tcp_rate_set));
 419                 rs->rs_ifp = ifp;
 420                 rs->rs_if_dunit = ifp->if_dunit;
 421                 rs->rs_flags = RS_IS_DEFF;
 422                 rs_number_alive++;
 423                 sysctl_ctx_init(&rs->sysctl_ctx);
 424                 rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 425                     SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl),
 426                     OID_AUTO,
 427                     rs->rs_ifp->if_xname,
 428                     CTLFLAG_RW, 0,
 429                     "");
 430                 rl_add_syctl_entries(rl_sysctl_root, rs);
 431                 mtx_lock(&rs_mtx);
 432                 CK_LIST_INSERT_HEAD(&int_rs, rs, next);
 433                 mtx_unlock(&rs_mtx);
 434                 return (rs);
 435         } else if ((rl.flags & RT_IS_FIXED_TABLE) == RT_IS_FIXED_TABLE) {
 436                 /* Mellanox most likely */
 437                 rs->rs_ifp = ifp;
 438                 rs->rs_if_dunit = ifp->if_dunit;
 439                 rs->rs_rate_cnt = rl.number_of_rates;
 440                 rs->rs_min_seg = rl.min_segment_burst;
 441                 rs->rs_highest_valid = 0;
 442                 rs->rs_flow_limit = rl.max_flows;
 443                 rs->rs_flags = RS_IS_INTF | RS_NO_PRE;
 444                 rs->rs_disable = 0;
 445                 rate_table_act = rl.rate_table;
 446         } else if ((rl.flags & RT_IS_SELECTABLE) == RT_IS_SELECTABLE) {
 447                 /* Chelsio */
 448                 rs->rs_ifp = ifp;
 449                 rs->rs_if_dunit = ifp->if_dunit;
 450                 rs->rs_rate_cnt = rl.number_of_rates;
 451                 rs->rs_min_seg = rl.min_segment_burst;
 452                 rs->rs_disable = 0;
 453                 rs->rs_flow_limit = rl.max_flows;
 454                 rate_table_act = desired_rates;
 455                 if ((rs->rs_rate_cnt > MAX_HDWR_RATES) &&
 456                     (rs->rs_rate_cnt < ALL_HARDWARE_RATES)) {
 457                         /*
 458                          * Our desired table is not big
 459                          * enough, do what we can.
 460                          */
 461                         rs->rs_rate_cnt = MAX_HDWR_RATES;
 462                  }
 463                 if (rs->rs_rate_cnt <= RS_ORDERED_COUNT)
 464                         rs->rs_flags = RS_IS_INTF;
 465                 else
 466                         rs->rs_flags = RS_IS_INTF | RS_INT_TBL;
 467                 if (rs->rs_rate_cnt >= ALL_HARDWARE_RATES)
 468                         rs->rs_rate_cnt = ALL_HARDWARE_RATES;
 469         } else {
 470                 printf("Interface:%s unit:%d not one known to have rate-limits\n",
 471                     ifp->if_dname,
 472                     ifp->if_dunit);
 473                 free(rs, M_TCPPACE);
 474                 return (NULL);
 475         }
 476         sz = sizeof(struct tcp_hwrate_limit_table) * rs->rs_rate_cnt;
 477         rs->rs_rlt = malloc(sz, M_TCPPACE, M_NOWAIT);
 478         if (rs->rs_rlt == NULL) {
 479                 if (error)
 480                         *error = ENOMEM;
 481 bail:
 482                 free(rs, M_TCPPACE);
 483                 return (NULL);
 484         }
 485         if (rs->rs_rate_cnt >= ALL_HARDWARE_RATES) {
 486                 /*
 487                  * The interface supports all
 488                  * the rates we could possibly want.
 489                  */
 490                 uint64_t rat;
 491
 492                 rs->rs_rlt[0].rate = 12500;     /* 100k */
 493                 rs->rs_rlt[1].rate = 25000;     /* 200k */
 494                 rs->rs_rlt[2].rate = 62500;     /* 500k */
 495                 /* Note 125000 == 1Megabit
 496                  * populate 1Meg - 1000meg.
 497                  */
 498                 for(i = 3, rat = 125000; i< (ALL_HARDWARE_RATES-1); i++) {
 499                         rs->rs_rlt[i].rate = rat;
 500                         rat += 125000;
 501                 }
 502                 rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate = 1250000000;
 503         } else if (rs->rs_flags & RS_INT_TBL) {
 504                 /* We populate this in a special way */
 505                 populate_canned_table(rs, rate_table_act);
 506         } else {
 507                 /*
 508                  * Just copy in the rates from
 509                  * the table, it is in order.
 510                  */
 511                 for (i=0; i<rs->rs_rate_cnt; i++) {
 512                         rs->rs_rlt[i].rate = rate_table_act[i];
 513                         rs->rs_rlt[i].time_between = 0;
 514                         rs->rs_rlt[i].flags = 0;
 515                 }
 516         }
 517         for (i = (rs->rs_rate_cnt - 1); i >= 0; i--) {
 518                 /*
 519                  * We go backwards through the list so that if we can't get
 520                  * a rate and fail to init one, we have at least a chance of
 521                  * getting the highest one.
 522                  */
 523                 rs->rs_rlt[i].ptbl = rs;
 524                 rs->rs_rlt[i].tag = NULL;
 525                 /*
 526                  * Calculate the time between.
 527                  */
 528                 lentim = ETHERNET_SEGMENT_SIZE * USECS_IN_SECOND;
 529                 res = lentim / rs->rs_rlt[i].rate;
 530                 if (res > 0)
 531                         rs->rs_rlt[i].time_between = res;
 532                 else
 533                         rs->rs_rlt[i].time_between = 1;
 534                 if (rs->rs_flags & RS_NO_PRE) {
 535                         rs->rs_rlt[i].flags = HDWRPACE_INITED;
 536                         rs->rs_lowest_valid = i;
 537                 } else {
 538                         int err;
 539 #ifdef RSS
 540                         hash_type = M_HASHTYPE_RSS_TCP_IPV4;
 541 #else
 542                         hash_type = M_HASHTYPE_OPAQUE_HASH;
 543 #endif
 544                         err = rl_attach_txrtlmt(ifp,
 545                             hash_type,
 546                             (i + 1),
 547                             rs->rs_rlt[i].rate,
 548                             &rs->rs_rlt[i].tag);
 549                         if (err) {
 550                                 if (i == (rs->rs_rate_cnt - 1)) {
 551                                         /*
 552                                          * Huh - first rate and we can't get
 553                                          * it?
 554                                          */
 555                                         free(rs->rs_rlt, M_TCPPACE);
 556                                         if (error)
 557                                                 *error = err;
 558                                         goto bail;
 559                                 } else {
 560                                         if (error)
 561                                                 *error = err;
 562                                 }
 563                                 break;
 564                         } else {
 565                                 rs->rs_rlt[i].flags = HDWRPACE_INITED | HDWRPACE_TAGPRESENT;
 566                                 rs->rs_lowest_valid = i;
 567                         }
 568                 }
 569         }
 570         /* Did we get at least 1 rate? */
 571         if (rs->rs_rlt[(rs->rs_rate_cnt - 1)].flags & HDWRPACE_INITED)
 572                 rs->rs_highest_valid = rs->rs_rate_cnt - 1;
 573         else {
 574                 free(rs->rs_rlt, M_TCPPACE);
 575                 goto bail;
 576         }
 577         rs_number_alive++;
 578         sysctl_ctx_init(&rs->sysctl_ctx);
 579         rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx,
 580             SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl),
 581             OID_AUTO,
 582             rs->rs_ifp->if_xname,
 583             CTLFLAG_RW, 0,
 584             "");
 585         rl_add_syctl_entries(rl_sysctl_root, rs);
 586         mtx_lock(&rs_mtx);
 587         CK_LIST_INSERT_HEAD(&int_rs, rs, next);
 588         mtx_unlock(&rs_mtx);
 589         return (rs);
 590 }
 591
 592 static const struct tcp_hwrate_limit_table *
 593 tcp_int_find_suitable_rate(const struct tcp_rate_set *rs,
 594     uint64_t bytes_per_sec, uint32_t flags)
 595 {
 596         struct tcp_hwrate_limit_table *arte = NULL, *rte = NULL;
 597         uint64_t mbits_per_sec, ind_calc;
 598         int i;
 599
 600         mbits_per_sec = (bytes_per_sec * 8);
 601         if (flags & RS_PACING_LT) {
 602                 if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) &&
 603                     (rs->rs_lowest_valid <= 2)){
 604                         /*
 605                          * Smaller than 1Meg, only
 606                          * 3 entries can match it.
 607                          */
 608                         for(i = rs->rs_lowest_valid; i < 3; i++) {
 609                                 if (bytes_per_sec <= rs->rs_rlt[i].rate) {
 610                                         rte = &rs->rs_rlt[i];
 611                                         break;
 612                                 } else if (rs->rs_rlt[i].flags & HDWRPACE_INITED) {
 613                                         arte = &rs->rs_rlt[i];
 614                                 }
 615                         }
 616                         goto done;
 617                 } else if ((mbits_per_sec > RS_ONE_GIGABIT_PERSEC) &&
 618                            (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)){
 619                         /*
 620                          * Larger than 1G (the majority of
 621                          * our table.
 622                          */
 623                         if (mbits_per_sec < RS_TEN_GIGABIT_PERSEC)
 624                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 625                         else
 626                                 arte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 627                         goto done;
 628                 }
 629                 /*
 630                  * If we reach here its in our table (between 1Meg - 1000Meg),
 631                  * just take the rounded down mbits per second, and add
 632                  * 1Megabit to it, from this we can calculate
 633                  * the index in the table.
 634                  */
 635                 ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC;
 636                 if ((ind_calc * RS_ONE_MEGABIT_PERSEC) != mbits_per_sec)
 637                         ind_calc++;
 638                 /* our table is offset by 3, we add 2 */
 639                 ind_calc += 2;
 640                 if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 641                         /* This should not happen */
 642                         ind_calc = ALL_HARDWARE_RATES-1;
 643                 }
 644                 if ((ind_calc >= rs->rs_lowest_valid) &&
 645                     (ind_calc <= rs->rs_highest_valid))
 646                 rte = &rs->rs_rlt[ind_calc];
 647         } else if (flags & RS_PACING_EXACT_MATCH) {
 648                 if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) &&
 649                     (rs->rs_lowest_valid <= 2)){
 650                         for(i = rs->rs_lowest_valid; i < 3; i++) {
 651                                 if (bytes_per_sec == rs->rs_rlt[i].rate) {
 652                                         rte = &rs->rs_rlt[i];
 653                                         break;
 654                                 }
 655                         }
 656                 } else if ((mbits_per_sec > RS_ONE_GIGABIT_PERSEC) &&
 657                            (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)) {
 658                         /* > 1Gbps only one rate */
 659                         if (bytes_per_sec == rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) {
 660                                 /* Its 10G wow */
 661                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 662                         }
 663                 } else {
 664                         /* Ok it must be a exact meg (its between 1G and 1Meg) */
 665                         ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC;
 666                         if ((ind_calc * RS_ONE_MEGABIT_PERSEC) == mbits_per_sec) {
 667                                 /* its an exact Mbps */
 668                                 ind_calc += 2;
 669                                 if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 670                                         /* This should not happen */
 671                                         ind_calc = ALL_HARDWARE_RATES-1;
 672                                 }
 673                                 if (rs->rs_rlt[ind_calc].flags & HDWRPACE_INITED)
 674                                         rte = &rs->rs_rlt[ind_calc];
 675                         }
 676                 }
 677         } else {
 678                 /* we want greater than the requested rate */
 679                 if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) &&
 680                     (rs->rs_lowest_valid <= 2)){
 681                         arte = &rs->rs_rlt[3]; /* set alternate to 1Meg */
 682                         for (i=2; i>=rs->rs_lowest_valid; i--) {
 683                                 if (bytes_per_sec < rs->rs_rlt[i].rate) {
 684                                         rte = &rs->rs_rlt[i];
 685                                         break;
 686                                 } else if ((flags & RS_PACING_GEQ) &&
 687                                            (bytes_per_sec == rs->rs_rlt[i].rate)) {
 688                                         rte = &rs->rs_rlt[i];
 689                                         break;
 690                                 } else {
 691                                         arte = &rs->rs_rlt[i]; /* new alternate */
 692                                 }
 693                         }
 694                 } else if (mbits_per_sec > RS_ONE_GIGABIT_PERSEC) {
 695                         if ((bytes_per_sec < rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) &&
 696                             (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)){
 697                                 /* Our top rate is larger than the request */
 698                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 699                         } else if ((flags & RS_PACING_GEQ) &&
 700                                    (bytes_per_sec == rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) &&
 701                                    (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)) {
 702                                 /* It matches our top rate */
 703                                 rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 704                         } else if (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED) {
 705                                 /* The top rate is an alternative */
 706                                 arte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)];
 707                         }
 708                 } else {
 709                         /* Its in our range 1Meg - 1Gig */
 710                         if (flags & RS_PACING_GEQ) {
 711                                 ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC;
 712                                 if ((ind_calc * RS_ONE_MEGABIT_PERSEC) == mbits_per_sec) {
 713                                         if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 714                                                 /* This should not happen */
 715                                                 ind_calc = (ALL_HARDWARE_RATES-1);
 716                                         }
 717                                         rte = &rs->rs_rlt[ind_calc];
 718                                 }
 719                                 goto done;
 720                         }
 721                         ind_calc = (mbits_per_sec + (RS_ONE_MEGABIT_PERSEC-1))/RS_ONE_MEGABIT_PERSEC;
 722                         ind_calc += 2;
 723                         if (ind_calc > (ALL_HARDWARE_RATES-1)) {
 724                                 /* This should not happen */
 725                                 ind_calc = ALL_HARDWARE_RATES-1;
 726                         }
 727                         if (rs->rs_rlt[ind_calc].flags & HDWRPACE_INITED)
 728                                 rte = &rs->rs_rlt[ind_calc];
 729                 }
 730         }
 731 done:
 732         if ((rte == NULL) &&
 733             (arte != NULL) &&
 734             (flags & RS_PACING_SUB_OK)) {
 735                 /* We can use the substitute */
 736                 rte = arte;
 737         }
 738         return (rte);
 739 }
 740
 741 static const struct tcp_hwrate_limit_table *
 742 tcp_find_suitable_rate(const struct tcp_rate_set *rs, uint64_t bytes_per_sec, uint32_t flags)
 743 {
 744         /**
 745          * Hunt the rate table with the restrictions in flags and find a
 746          * suitable rate if possible.
 747          * RS_PACING_EXACT_MATCH - look for an exact match to rate.
 748          * RS_PACING_GT     - must be greater than.
 749          * RS_PACING_GEQ    - must be greater than or equal.
 750          * RS_PACING_LT     - must be less than.
 751          * RS_PACING_SUB_OK - If we don't meet criteria a
 752          *                    substitute is ok.
 753          */
 754         int i, matched;
 755         struct tcp_hwrate_limit_table *rte = NULL;
 756
 757
 758         if ((rs->rs_flags & RS_INT_TBL) &&
 759             (rs->rs_rate_cnt >= ALL_HARDWARE_RATES)) {
 760                 /*
 761                  * Here we don't want to paw thru
 762                  * a big table, we have everything
 763                  * from 1Meg - 1000Meg in 1Meg increments.
 764                  * Use an alternate method to "lookup".
 765                  */
 766                 return (tcp_int_find_suitable_rate(rs, bytes_per_sec, flags));
 767         }
 768         if ((flags & RS_PACING_LT) ||
 769             (flags & RS_PACING_EXACT_MATCH)) {
 770                 /*
 771                  * For exact and less than we go forward through the table.
 772                  * This way when we find one larger we stop (exact was a
 773                  * toss up).
 774                  */
 775                 for (i = rs->rs_lowest_valid, matched = 0; i <= rs->rs_highest_valid; i++) {
 776                         if ((flags & RS_PACING_EXACT_MATCH) &&
 777                             (bytes_per_sec == rs->rs_rlt[i].rate)) {
 778                                 rte = &rs->rs_rlt[i];
 779                                 matched = 1;
 780                                 break;
 781                         } else if ((flags & RS_PACING_LT) &&
 782                             (bytes_per_sec <= rs->rs_rlt[i].rate)) {
 783                                 rte = &rs->rs_rlt[i];
 784                                 matched = 1;
 785                                 break;
 786                         }
 787                         if (bytes_per_sec > rs->rs_rlt[i].rate)
 788                                 break;
 789                 }
 790                 if ((matched == 0) &&
 791                     (flags & RS_PACING_LT) &&
 792                     (flags & RS_PACING_SUB_OK)) {
 793                         /* Kick in a substitute (the lowest) */
 794                         rte = &rs->rs_rlt[rs->rs_lowest_valid];
 795                 }
 796         } else {
 797                 /*
 798                  * Here we go backward through the table so that we can find
 799                  * the one greater in theory faster (but its probably a
 800                  * wash).
 801                  */
 802                 for (i = rs->rs_highest_valid, matched = 0; i >= rs->rs_lowest_valid; i--) {
 803                         if (rs->rs_rlt[i].rate > bytes_per_sec) {
 804                                 /* A possible candidate */
 805                                 rte = &rs->rs_rlt[i];
 806                         }
 807                         if ((flags & RS_PACING_GEQ) &&
 808                             (bytes_per_sec == rs->rs_rlt[i].rate)) {
 809                                 /* An exact match and we want equal */
 810                                 matched = 1;
 811                                 rte = &rs->rs_rlt[i];
 812                                 break;
 813                         } else if (rte) {
 814                                 /*
 815                                  * Found one that is larger than but don't
 816                                  * stop, there may be a more closer match.
 817                                  */
 818                                 matched = 1;
 819                         }
 820                         if (rs->rs_rlt[i].rate < bytes_per_sec) {
 821                                 /*
 822                                  * We found a table entry that is smaller,
 823                                  * stop there will be none greater or equal.
 824                                  */
 825                                 break;
 826                         }
 827                 }
 828                 if ((matched == 0) &&
 829                     (flags & RS_PACING_SUB_OK)) {
 830                         /* Kick in a substitute (the highest) */
 831                         rte = &rs->rs_rlt[rs->rs_highest_valid];
 832                 }
 833         }
 834         return (rte);
 835 }
 836
 837 static struct ifnet *
 838 rt_find_real_interface(struct ifnet *ifp, struct inpcb *inp, int *error)
 839 {
 840         struct ifnet *tifp;
 841         struct m_snd_tag *tag;
 842         union if_snd_tag_alloc_params params = {
 843                 .rate_limit.hdr.type = IF_SND_TAG_TYPE_RATE_LIMIT,
 844                 .rate_limit.hdr.flowid = 1,
 845                 .rate_limit.max_rate = COMMON_RATE,
 846                 .rate_limit.flags = M_NOWAIT,
 847         };
 848         int err;
 849 #ifdef RSS
 850         params.rate_limit.hdr.flowtype = ((inp->inp_vflag & INP_IPV6) ?
 851             M_HASHTYPE_RSS_TCP_IPV6 : M_HASHTYPE_RSS_TCP_IPV4);
 852 #else
 853         params.rate_limit.hdr.flowtype = M_HASHTYPE_OPAQUE_HASH;
 854 #endif
 855         tag = NULL;
 856         if (ifp->if_snd_tag_alloc) {
 857                 if (error)
 858                         *error = ENODEV;
 859                 return (NULL);
 860         }
 861         err = ifp->if_snd_tag_alloc(ifp, &params, &tag);
 862         if (err) {
 863                 /* Failed to setup a tag? */
 864                 if (error)
 865                         *error = err;
 866                 return (NULL);
 867         }
 868         tifp = tag->ifp;
 869         tifp->if_snd_tag_free(tag);
 870         return (tifp);
 871 }
 872
 873 static const struct tcp_hwrate_limit_table *
 874 rt_setup_rate(struct inpcb *inp, struct ifnet *ifp, uint64_t bytes_per_sec,
 875     uint32_t flags, int *error)
 876 {
 877         /* First lets find the interface if it exists */
 878         const struct tcp_hwrate_limit_table *rte;
 879         struct tcp_rate_set *rs;
 880         struct epoch_tracker et;
 881         int err;
 882
 883         NET_EPOCH_ENTER(et);
 884 use_real_interface:
 885         CK_LIST_FOREACH(rs, &int_rs, next) {
 886                 /*
 887                  * Note we don't look with the lock since we either see a
 888                  * new entry or will get one when we try to add it.
 889                  */
 890                 if (rs->rs_flags & RS_IS_DEAD) {
 891                         /* The dead are not looked at */
 892                         continue;
 893                 }
 894                 if ((rs->rs_ifp == ifp) &&
 895                     (rs->rs_if_dunit == ifp->if_dunit)) {
 896                         /* Ok we found it */
 897                         break;
 898                 }
 899         }
 900         if ((rs == NULL) ||
 901             (rs->rs_flags & RS_INTF_NO_SUP) ||
 902             (rs->rs_flags & RS_IS_DEAD)) {
 903                 /*
 904                  * This means we got a packet *before*
 905                  * the IF-UP was processed below, <or>
 906                  * while or after we already received an interface
 907                  * departed event. In either case we really don't
 908                  * want to do anything with pacing, in
 909                  * the departing case the packet is not
 910                  * going to go very far. The new case
 911                  * might be arguable, but its impossible
 912                  * to tell from the departing case.
 913                  */
 914                 if (rs->rs_disable && error)
 915                         *error = ENODEV;
 916                 NET_EPOCH_EXIT(et);
 917                 return (NULL);
 918         }
 919
 920         if ((rs == NULL) || (rs->rs_disable != 0)) {
 921                 if (rs->rs_disable && error)
 922                         *error = ENOSPC;
 923                 NET_EPOCH_EXIT(et);
 924                 return (NULL);
 925         }
 926         if (rs->rs_flags & RS_IS_DEFF) {
 927                 /* We need to find the real interface */
 928                 struct ifnet *tifp;
 929
 930                 tifp = rt_find_real_interface(ifp, inp, error);
 931                 if (tifp == NULL) {
 932                         if (rs->rs_disable && error)
 933                                 *error = ENOTSUP;
 934                         NET_EPOCH_EXIT(et);
 935                         return (NULL);
 936                 }
 937                 goto use_real_interface;
 938         }
 939         if (rs->rs_flow_limit &&
 940             ((rs->rs_flows_using + 1) > rs->rs_flow_limit)) {
 941                 if (error)
 942                         *error = ENOSPC;
 943                 NET_EPOCH_EXIT(et);
 944                 return (NULL);
 945         }
 946         rte = tcp_find_suitable_rate(rs, bytes_per_sec, flags);
 947         if (rte) {
 948                 err = in_pcbattach_txrtlmt(inp, rs->rs_ifp,
 949                     inp->inp_flowtype,
 950                     inp->inp_flowid,
 951                     rte->rate,
 952                     &inp->inp_snd_tag);
 953                 if (err) {
 954                         /* Failed to attach */
 955                         if (error)
 956                                 *error = err;
 957                         rte = NULL;
 958                 }
 959         }
 960         if (rte) {
 961                 /*
 962                  * We use an atomic here for accounting so we don't have to
 963                  * use locks when freeing.
 964                  */
 965                 atomic_add_64(&rs->rs_flows_using, 1);
 966         }
 967         NET_EPOCH_EXIT(et);
 968         return (rte);
 969 }
 970
 971 static void
 972 tcp_rl_ifnet_link(void *arg __unused, struct ifnet *ifp, int link_state)
 973 {
 974         int error;
 975         struct tcp_rate_set *rs;
 976
 977         if (((ifp->if_capabilities & IFCAP_TXRTLMT) == 0) ||
 978             (link_state != LINK_STATE_UP)) {
 979                 /*
 980                  * We only care on an interface going up that is rate-limit
 981                  * capable.
 982                  */
 983                 return;
 984         }
 985         mtx_lock(&rs_mtx);
 986         CK_LIST_FOREACH(rs, &int_rs, next) {
 987                 if ((rs->rs_ifp == ifp) &&
 988                     (rs->rs_if_dunit == ifp->if_dunit)) {
 989                         /* We already have initialized this guy */
 990                         mtx_unlock(&rs_mtx);
 991                         return;
 992                 }
 993         }
 994         mtx_unlock(&rs_mtx);
 995         rt_setup_new_rs(ifp, &error);
 996 }
 997
 998 static void
 999 tcp_rl_ifnet_departure(void *arg __unused, struct ifnet *ifp)
1000 {
1001         struct tcp_rate_set *rs, *nrs;
1002         struct ifnet *tifp;
1003         int i;
1004
1005         mtx_lock(&rs_mtx);
1006         CK_LIST_FOREACH_SAFE(rs, &int_rs, next, nrs) {
1007                 if ((rs->rs_ifp == ifp) &&
1008                     (rs->rs_if_dunit == ifp->if_dunit)) {
1009                         CK_LIST_REMOVE(rs, next);
1010                         rs_number_alive--;
1011                         rs->rs_flags |= RS_IS_DEAD;
1012                         for (i = 0; i < rs->rs_rate_cnt; i++) {
1013                                 if (rs->rs_rlt[i].flags & HDWRPACE_TAGPRESENT) {
1014                                         tifp = rs->rs_rlt[i].tag->ifp;
1015                                         in_pcbdetach_tag(tifp, rs->rs_rlt[i].tag);
1016                                         rs->rs_rlt[i].tag = NULL;
1017                                 }
1018                                 rs->rs_rlt[i].flags = HDWRPACE_IFPDEPARTED;
1019                         }
1020                         if (rs->rs_flows_using == 0)
1021                                 rs_defer_destroy(rs);
1022                         break;
1023                 }
1024         }
1025         mtx_unlock(&rs_mtx);
1026 }
1027
1028 static void
1029 tcp_rl_shutdown(void *arg __unused, int howto __unused)
1030 {
1031         struct tcp_rate_set *rs, *nrs;
1032         struct ifnet *tifp;
1033         int i;
1034
1035         mtx_lock(&rs_mtx);
1036         CK_LIST_FOREACH_SAFE(rs, &int_rs, next, nrs) {
1037                 CK_LIST_REMOVE(rs, next);
1038                 rs_number_alive--;
1039                 rs->rs_flags |= RS_IS_DEAD;
1040                 for (i = 0; i < rs->rs_rate_cnt; i++) {
1041                         if (rs->rs_rlt[i].flags & HDWRPACE_TAGPRESENT) {
1042                                 tifp = rs->rs_rlt[i].tag->ifp;
1043                                 in_pcbdetach_tag(tifp, rs->rs_rlt[i].tag);
1044                                 rs->rs_rlt[i].tag = NULL;
1045                         }
1046                         rs->rs_rlt[i].flags = HDWRPACE_IFPDEPARTED;
1047                 }
1048                 if (rs->rs_flows_using == 0)
1049                         rs_defer_destroy(rs);
1050         }
1051         mtx_unlock(&rs_mtx);
1052 }
1053
1054 const struct tcp_hwrate_limit_table *
1055 tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp,
1056     uint64_t bytes_per_sec, int flags, int *error)
1057 {
1058         const struct tcp_hwrate_limit_table *rte;
1059
1060         if (tp->t_inpcb->inp_snd_tag == NULL) {
1061                 /*
1062                  * We are setting up a rate for the first time.
1063                  */
1064                 if ((ifp->if_capabilities & IFCAP_TXRTLMT) == 0) {
1065                         /* Not supported by the egress */
1066                         if (error)
1067                                 *error = ENODEV;
1068                         return (NULL);
1069                 }
1070 #ifdef KERN_TLS
1071                 if (tp->t_inpcb->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) {
1072                         /*
1073                          * We currently can't do both TLS and hardware
1074                          * pacing
1075                          */
1076                         if (error)
1077                                 *error = EINVAL;
1078                         return (NULL);
1079                 }
1080 #endif
1081                 rte = rt_setup_rate(tp->t_inpcb, ifp, bytes_per_sec, flags, error);
1082         } else {
1083                 /*
1084                  * We are modifying a rate, wrong interface?
1085                  */
1086                 if (error)
1087                         *error = EINVAL;
1088                 rte = NULL;
1089         }
1090         return (rte);
1091 }
1092
1093 const struct tcp_hwrate_limit_table *
1094 tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte,
1095     struct tcpcb *tp, struct ifnet *ifp,
1096     uint64_t bytes_per_sec, int flags, int *error)
1097 {
1098         const struct tcp_hwrate_limit_table *nrte;
1099         const struct tcp_rate_set *rs;
1100         int is_indirect = 0;
1101         int err;
1102
1103
1104         if ((tp->t_inpcb->inp_snd_tag == NULL) ||
1105             (crte == NULL)) {
1106                 /* Wrong interface */
1107                 if (error)
1108                         *error = EINVAL;
1109                 return (NULL);
1110         }
1111         rs = crte->ptbl;
1112         if ((rs->rs_flags & RS_IS_DEAD) ||
1113             (crte->flags & HDWRPACE_IFPDEPARTED)) {
1114                 /* Release the rate, and try anew */
1115 re_rate:
1116                 tcp_rel_pacing_rate(crte, tp);
1117                 nrte = tcp_set_pacing_rate(tp, ifp,
1118                     bytes_per_sec, flags, error);
1119                 return (nrte);
1120         }
1121         if ((rs->rs_flags & RT_IS_INDIRECT ) == RT_IS_INDIRECT)
1122                 is_indirect = 1;
1123         else
1124                 is_indirect = 0;
1125         if ((is_indirect == 0) &&
1126             ((ifp != rs->rs_ifp) ||
1127             (ifp->if_dunit != rs->rs_if_dunit))) {
1128                 /*
1129                  * Something changed, the user is not pointing to the same
1130                  * ifp? Maybe a route updated on this guy?
1131                  */
1132                 goto re_rate;
1133         } else if (is_indirect) {
1134                 /*
1135                  * For indirect we have to dig in and find the real interface.
1136                  */
1137                 struct ifnet *rifp;
1138
1139                 rifp = rt_find_real_interface(ifp, tp->t_inpcb, error);
1140                 if (rifp == NULL) {
1141                         /* Can't find it? */
1142                         goto re_rate;
1143                 }
1144                 if ((rifp != rs->rs_ifp) ||
1145                     (ifp->if_dunit != rs->rs_if_dunit)) {
1146                         goto re_rate;
1147                 }
1148         }
1149         nrte = tcp_find_suitable_rate(rs, bytes_per_sec, flags);
1150         if (nrte == crte) {
1151                 /* No change */
1152                 if (error)
1153                         *error = 0;
1154                 return (crte);
1155         }
1156         if (nrte == NULL) {
1157                 /* Release the old rate */
1158                 tcp_rel_pacing_rate(crte, tp);
1159                 return (NULL);
1160         }
1161         /* Change rates to our new entry */
1162         err = in_pcbmodify_txrtlmt(tp->t_inpcb, nrte->rate);
1163         if (err) {
1164                 if (error)
1165                         *error = err;
1166                 return (NULL);
1167         }
1168         if (error)
1169                 *error = 0;
1170         return (nrte);
1171 }
1172
1173 void
1174 tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, struct tcpcb *tp)
1175 {
1176         const struct tcp_rate_set *crs;
1177         struct tcp_rate_set *rs;
1178         uint64_t pre;
1179
1180         crs = crte->ptbl;
1181         /*
1182          * Now we must break the const
1183          * in order to release our refcount.
1184          */
1185         rs = __DECONST(struct tcp_rate_set *, crs);
1186         pre = atomic_fetchadd_64(&rs->rs_flows_using, -1);
1187         if (pre == 1) {
1188                 mtx_lock(&rs_mtx);
1189                 /*
1190                  * Is it dead?
1191                  */
1192                 if (rs->rs_flags & RS_IS_DEAD)
1193                         rs_defer_destroy(rs);
1194                 mtx_unlock(&rs_mtx);
1195         }
1196         in_pcbdetach_txrtlmt(tp->t_inpcb);
1197 }
1198
1199 static eventhandler_tag rl_ifnet_departs;
1200 static eventhandler_tag rl_ifnet_arrives;
1201 static eventhandler_tag rl_shutdown_start;
1202
1203 static void
1204 tcp_rs_init(void *st __unused)
1205 {
1206         CK_LIST_INIT(&int_rs);
1207         rs_number_alive = 0;
1208         rs_number_dead = 0;;
1209         mtx_init(&rs_mtx, "tcp_rs_mtx", "rsmtx", MTX_DEF);
1210         rl_ifnet_departs = EVENTHANDLER_REGISTER(ifnet_departure_event,
1211             tcp_rl_ifnet_departure,
1212             NULL, EVENTHANDLER_PRI_ANY);
1213         rl_ifnet_arrives = EVENTHANDLER_REGISTER(ifnet_link_event,
1214             tcp_rl_ifnet_link,
1215             NULL, EVENTHANDLER_PRI_ANY);
1216         rl_shutdown_start = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1217             tcp_rl_shutdown, NULL,
1218             SHUTDOWN_PRI_FIRST);
1219         printf("TCP_ratelimit: Is now initialized\n");
1220 }
1221
1222 SYSINIT(tcp_rl_init, SI_SUB_SMP + 1, SI_ORDER_ANY, tcp_rs_init, NULL);
1223 #endif