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authorNeale Ranns <neale.ranns@cisco.com>2018-01-09 04:11:28 -0800
committerNeale Ranns <nranns@cisco.com>2018-01-09 13:49:50 +0000
commiteea537a288721b867d65b736363ab3f71ba6116c (patch)
treea9eb23c91b9f1f8f7c6e6ab723748c2317c7e848 /test/vpp_ip_route.py
parent52fae862646e25bac6d1cd11b9fc7ac77299bc25 (diff)
BIER: missing endian swap for imposition object in API return
Change-Id: Iddd754d00ace3d042336e5c2c40431566275051a Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
Diffstat (limited to 'test/vpp_ip_route.py')
-rw-r--r--test/vpp_ip_route.py1
1 files changed, 1 insertions, 0 deletions
diff --git a/test/vpp_ip_route.py b/test/vpp_ip_route.py
index 3bc3b65111c..fedf1302e21 100644
--- a/test/vpp_ip_route.py
+++ b/test/vpp_ip_route.py
@@ -308,6 +308,7 @@ class VppIpMRoute(VppObject):
path.nh_itf,
path.nh_i_flags,
table_id=self.table_id,
+ bier_imp=path.bier_imp,
is_add=0,
is_ipv6=self.is_ip6)
/a> 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 
/*
 * Copyright (c) 2017 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/**
 * @file
 * @brief Session and session manager
 */

#include <vnet/session/session.h>
#include <vnet/session/session_debug.h>
#include <vnet/session/application.h>
#include <vlibmemory/api.h>
#include <vnet/dpo/load_balance.h>
#include <vnet/fib/ip4_fib.h>
#include <vnet/tcp/tcp.h>

session_manager_main_t session_manager_main;
extern transport_proto_vft_t *tp_vfts;

static void
session_send_evt_to_thread (u64 session_handle, fifo_event_type_t evt_type,
			    u32 thread_index, void *fp, void *rpc_args)
{
  u32 tries = 0;
  session_fifo_event_t evt = { {0}, };
  unix_shared_memory_queue_t *q;

  evt.event_type = evt_type;
  if (evt_type == FIFO_EVENT_RPC)
    {
      evt.rpc_args.fp = fp;
      evt.rpc_args.arg = rpc_args;
    }
  else
    evt.session_handle = session_handle;

  q = session_manager_get_vpp_event_queue (thread_index);
  while (unix_shared_memory_queue_add (q, (u8 *) & evt, 1))
    {
      if (tries++ == 3)
	{
	  SESSION_DBG ("failed to enqueue evt");
	  break;
	}
    }
}

void
session_send_session_evt_to_thread (u64 session_handle,
				    fifo_event_type_t evt_type,
				    u32 thread_index)
{
  session_send_evt_to_thread (session_handle, evt_type, thread_index, 0, 0);
}

void
session_send_rpc_evt_to_thread (u32 thread_index, void *fp, void *rpc_args)
{
  if (thread_index != vlib_get_thread_index ())
    session_send_evt_to_thread (0, FIFO_EVENT_RPC, thread_index, fp,
				rpc_args);
  else
    {
      void (*fnp) (void *) = fp;
      fnp (rpc_args);
    }
}

stream_session_t *
session_alloc (u32 thread_index)
{
  session_manager_main_t *smm = &session_manager_main;
  stream_session_t *s;
  u8 will_expand = 0;
  pool_get_aligned_will_expand (smm->sessions[thread_index], will_expand,
				CLIB_CACHE_LINE_BYTES);
  /* If we have peekers, let them finish */
  if (PREDICT_FALSE (will_expand))
    {
      clib_spinlock_lock_if_init (&smm->peekers_write_locks[thread_index]);
      pool_get_aligned (session_manager_main.sessions[thread_index], s,
			CLIB_CACHE_LINE_BYTES);
      clib_spinlock_unlock_if_init (&smm->peekers_write_locks[thread_index]);
    }
  else
    {
      pool_get_aligned (session_manager_main.sessions[thread_index], s,
			CLIB_CACHE_LINE_BYTES);
    }
  memset (s, 0, sizeof (*s));
  s->session_index = s - session_manager_main.sessions[thread_index];
  s->thread_index = thread_index;
  return s;
}

static void
session_free (stream_session_t * s)
{
  pool_put (session_manager_main.sessions[s->thread_index], s);
  if (CLIB_DEBUG)
    memset (s, 0xFA, sizeof (*s));
}

static int
session_alloc_fifos (segment_manager_t * sm, stream_session_t * s)
{
  svm_fifo_t *server_rx_fifo = 0, *server_tx_fifo = 0;
  u32 fifo_segment_index;
  int rv;

  if ((rv = segment_manager_alloc_session_fifos (sm, &server_rx_fifo,
						 &server_tx_fifo,
						 &fifo_segment_index)))
    return rv;
  /* Initialize backpointers */
  server_rx_fifo->master_session_index = s->session_index;
  server_rx_fifo->master_thread_index = s->thread_index;

  server_tx_fifo->master_session_index = s->session_index;
  server_tx_fifo->master_thread_index = s->thread_index;

  s->server_rx_fifo = server_rx_fifo;
  s->server_tx_fifo = server_tx_fifo;
  s->svm_segment_index = fifo_segment_index;
  return 0;
}

static stream_session_t *
session_alloc_for_connection (transport_connection_t * tc)
{
  stream_session_t *s;
  u32 thread_index = tc->thread_index;

  ASSERT (thread_index == vlib_get_thread_index ());

  s = session_alloc (thread_index);
  s->session_type = session_type_from_proto_and_ip (tc->proto, tc->is_ip4);
  s->session_state = SESSION_STATE_CONNECTING;
  s->thread_index = thread_index;

  /* Attach transport to session and vice versa */
  s->connection_index = tc->c_index;
  tc->s_index = s->session_index;
  return s;
}

static int
session_alloc_and_init (segment_manager_t * sm, transport_connection_t * tc,
			u8 alloc_fifos, stream_session_t ** ret_s)
{
  stream_session_t *s;
  int rv;

  s = session_alloc_for_connection (tc);
  if (alloc_fifos && (rv = session_alloc_fifos (sm, s)))
    {
      session_free (s);
      return rv;
    }

  /* Add to the main lookup table */
  session_lookup_add_connection (tc, session_handle (s));

  *ret_s = s;
  return 0;
}

/**
 * Discards bytes from buffer chain
 *
 * It discards n_bytes_to_drop starting at first buffer after chain_b
 */
always_inline void
session_enqueue_discard_chain_bytes (vlib_main_t * vm, vlib_buffer_t * b,
				     vlib_buffer_t ** chain_b,
				     u32 n_bytes_to_drop)
{
  vlib_buffer_t *next = *chain_b;
  u32 to_drop = n_bytes_to_drop;
  ASSERT (b->flags & VLIB_BUFFER_NEXT_PRESENT);
  while (to_drop && (next->flags & VLIB_BUFFER_NEXT_PRESENT))
    {
      next = vlib_get_buffer (vm, next->next_buffer);
      if (next->current_length > to_drop)
	{
	  vlib_buffer_advance (next, to_drop);
	  to_drop = 0;
	}
      else
	{
	  to_drop -= next->current_length;
	  next->current_length = 0;
	}
    }
  *chain_b = next;

  if (to_drop == 0)
    b->total_length_not_including_first_buffer -= n_bytes_to_drop;
}

/**
 * Enqueue buffer chain tail
 */
always_inline int
session_enqueue_chain_tail (stream_session_t * s, vlib_buffer_t * b,
			    u32 offset, u8 is_in_order)
{
  vlib_buffer_t *chain_b;
  u32 chain_bi, len, diff;
  vlib_main_t *vm = vlib_get_main ();
  u8 *data;
  u32 written = 0;
  int rv = 0;

  if (is_in_order && offset)
    {
      diff = offset - b->current_length;
      if (diff > b->total_length_not_including_first_buffer)
	return 0;
      chain_b = b;
      session_enqueue_discard_chain_bytes (vm, b, &chain_b, diff);
      chain_bi = vlib_get_buffer_index (vm, chain_b);
    }
  else
    chain_bi = b->next_buffer;

  do
    {
      chain_b = vlib_get_buffer (vm, chain_bi);
      data = vlib_buffer_get_current (chain_b);
      len = chain_b->current_length;
      if (!len)
	continue;
      if (is_in_order)
	{
	  rv = svm_fifo_enqueue_nowait (s->server_rx_fifo, len, data);
	  if (rv == len)
	    {
	      written += rv;
	    }
	  else if (rv < len)
	    {
	      return (rv > 0) ? (written + rv) : written;
	    }
	  else if (rv > len)
	    {
	      written += rv;

	      /* written more than what was left in chain */
	      if (written > b->total_length_not_including_first_buffer)
		return written;

	      /* drop the bytes that have already been delivered */
	      session_enqueue_discard_chain_bytes (vm, b, &chain_b, rv - len);
	    }
	}
      else
	{
	  rv = svm_fifo_enqueue_with_offset (s->server_rx_fifo, offset, len,
					     data);
	  if (rv)
	    {
	      clib_warning ("failed to enqueue multi-buffer seg");
	      return -1;
	    }
	  offset += len;
	}
    }
  while ((chain_bi = (chain_b->flags & VLIB_BUFFER_NEXT_PRESENT)
	  ? chain_b->next_buffer : 0));

  if (is_in_order)
    return written;

  return 0;
}

/*
 * Enqueue data for delivery to session peer. Does not notify peer of enqueue
 * event but on request can queue notification events for later delivery by
 * calling stream_server_flush_enqueue_events().
 *
 * @param tc Transport connection which is to be enqueued data
 * @param b Buffer to be enqueued
 * @param offset Offset at which to start enqueueing if out-of-order
 * @param queue_event Flag to indicate if peer is to be notified or if event
 *                    is to be queued. The former is useful when more data is
 *                    enqueued and only one event is to be generated.
 * @param is_in_order Flag to indicate if data is in order
 * @return Number of bytes enqueued or a negative value if enqueueing failed.
 */
int
session_enqueue_stream_connection (transport_connection_t * tc,
				   vlib_buffer_t * b, u32 offset,
				   u8 queue_event, u8 is_in_order)
{
  stream_session_t *s;
  int enqueued = 0, rv, in_order_off;

  s = session_get (tc->s_index, tc->thread_index);

  if (is_in_order)
    {
      enqueued = svm_fifo_enqueue_nowait (s->server_rx_fifo,
					  b->current_length,
					  vlib_buffer_get_current (b));
      if (PREDICT_FALSE ((b->flags & VLIB_BUFFER_NEXT_PRESENT)
			 && enqueued >= 0))
	{
	  in_order_off = enqueued > b->current_length ? enqueued : 0;
	  rv = session_enqueue_chain_tail (s, b, in_order_off, 1);
	  if (rv > 0)
	    enqueued += rv;
	}
    }
  else
    {
      rv = svm_fifo_enqueue_with_offset (s->server_rx_fifo, offset,
					 b->current_length,
					 vlib_buffer_get_current (b));
      if (PREDICT_FALSE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) && !rv))
	session_enqueue_chain_tail (s, b, offset + b->current_length, 0);
      /* if something was enqueued, report even this as success for ooo
       * segment handling */
      return rv;
    }

  if (queue_event)
    {
      /* Queue RX event on this fifo. Eventually these will need to be flushed
       * by calling stream_server_flush_enqueue_events () */
      session_manager_main_t *smm = vnet_get_session_manager_main ();
      u32 thread_index = s->thread_index;
      u32 enqueue_epoch = smm->current_enqueue_epoch[tc->proto][thread_index];

      if (s->enqueue_epoch != enqueue_epoch)
	{
	  s->enqueue_epoch = enqueue_epoch;
	  vec_add1 (smm->session_to_enqueue[tc->proto][thread_index],
		    s - smm->sessions[thread_index]);
	}
    }

  return enqueued;
}

int
session_enqueue_dgram_connection (stream_session_t * s, vlib_buffer_t * b,
				  u8 proto, u8 queue_event)
{
  int enqueued = 0, rv, in_order_off;

  if (svm_fifo_max_enqueue (s->server_rx_fifo) < b->current_length)
    return -1;
  enqueued = svm_fifo_enqueue_nowait (s->server_rx_fifo, b->current_length,
				      vlib_buffer_get_current (b));
  if (PREDICT_FALSE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) && enqueued >= 0))
    {
      in_order_off = enqueued > b->current_length ? enqueued : 0;
      rv = session_enqueue_chain_tail (s, b, in_order_off, 1);
      if (rv > 0)
	enqueued += rv;
    }
  if (queue_event)
    {
      /* Queue RX event on this fifo. Eventually these will need to be flushed
       * by calling stream_server_flush_enqueue_events () */
      session_manager_main_t *smm = vnet_get_session_manager_main ();
      u32 thread_index = s->thread_index;
      u32 enqueue_epoch = smm->current_enqueue_epoch[proto][thread_index];

      if (s->enqueue_epoch != enqueue_epoch)
	{
	  s->enqueue_epoch = enqueue_epoch;
	  vec_add1 (smm->session_to_enqueue[proto][thread_index],
		    s - smm->sessions[thread_index]);
	}
    }
  return enqueued;
}

/** Check if we have space in rx fifo to push more bytes */
u8
stream_session_no_space (transport_connection_t * tc, u32 thread_index,
			 u16 data_len)
{
  stream_session_t *s = session_get (tc->s_index, thread_index);

  if (PREDICT_FALSE (s->session_state != SESSION_STATE_READY))
    return 1;

  if (data_len > svm_fifo_max_enqueue (s->server_rx_fifo))
    return 1;

  return 0;
}

u32
stream_session_tx_fifo_max_dequeue (transport_connection_t * tc)
{
  stream_session_t *s = session_get (tc->s_index, tc->thread_index);
  if (!s->server_tx_fifo)
    return 0;
  return svm_fifo_max_dequeue (s->server_tx_fifo);
}

int
stream_session_peek_bytes (transport_connection_t * tc, u8 * buffer,
			   u32 offset, u32 max_bytes)
{
  stream_session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_peek (s->server_tx_fifo, offset, max_bytes, buffer);
}

u32
stream_session_dequeue_drop (transport_connection_t * tc, u32 max_bytes)
{
  stream_session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_dequeue_drop (s->server_tx_fifo, max_bytes);
}

/**
 * Notify session peer that new data has been enqueued.
 *
 * @param s Stream session for which the event is to be generated.
 * @param block Flag to indicate if call should block if event queue is full.
 *
 * @return 0 on succes or negative number if failed to send notification.
 */
static int
session_enqueue_notify (stream_session_t * s, u8 block)
{
  application_t *app;
  session_fifo_event_t evt;
  unix_shared_memory_queue_t *q;

  if (PREDICT_FALSE (s->session_state == SESSION_STATE_CLOSED))
    {
      /* Session is closed so app will never clean up. Flush rx fifo */
      u32 to_dequeue = svm_fifo_max_dequeue (s->server_rx_fifo);
      if (to_dequeue)
	svm_fifo_dequeue_drop (s->server_rx_fifo, to_dequeue);
      return 0;
    }

  /* Get session's server */
  app = application_get_if_valid (s->app_index);

  if (PREDICT_FALSE (app == 0))
    {
      clib_warning ("invalid s->app_index = %d", s->app_index);
      return 0;
    }

  /* Built-in server? Hand event to the callback... */
  if (app->cb_fns.builtin_server_rx_callback)
    return app->cb_fns.builtin_server_rx_callback (s);

  /* If no event, send one */
  if (svm_fifo_set_event (s->server_rx_fifo))
    {
      /* Fabricate event */
      evt.fifo = s->server_rx_fifo;
      evt.event_type = FIFO_EVENT_APP_RX;

      /* Add event to server's event queue */
      q = app->event_queue;

      /* Based on request block (or not) for lack of space */
      if (block || PREDICT_TRUE (q->cursize < q->maxsize))
	unix_shared_memory_queue_add (app->event_queue, (u8 *) & evt,
				      0 /* do wait for mutex */ );
      else
	{
	  clib_warning ("fifo full");
	  return -1;
	}
    }

  /* *INDENT-OFF* */
  SESSION_EVT_DBG(SESSION_EVT_ENQ, s, ({
      ed->data[0] = evt.event_type;
      ed->data[1] = svm_fifo_max_dequeue (s->server_rx_fifo);
  }));
  /* *INDENT-ON* */

  return 0;
}

/**
 * Flushes queue of sessions that are to be notified of new data
 * enqueued events.
 *
 * @param thread_index Thread index for which the flush is to be performed.
 * @return 0 on success or a positive number indicating the number of
 *         failures due to API queue being full.
 */
int
session_manager_flush_enqueue_events (u8 transport_proto, u32 thread_index)
{
  session_manager_main_t *smm = &session_manager_main;
  u32 *indices;
  stream_session_t *s;
  int i, errors = 0;

  indices = smm->session_to_enqueue[transport_proto][thread_index];

  for (i = 0; i < vec_len (indices); i++)
    {
      s = session_get_if_valid (indices[i], thread_index);
      if (s == 0 || session_enqueue_notify (s, 0 /* don't block */ ))
	errors++;
    }

  vec_reset_length (indices);
  smm->session_to_enqueue[transport_proto][thread_index] = indices;
  smm->current_enqueue_epoch[transport_proto][thread_index]++;

  return errors;
}

/**
 * Init fifo tail and head pointers
 *
 * Useful if transport uses absolute offsets for tracking ooo segments.
 */
void
stream_session_init_fifos_pointers (transport_connection_t * tc,
				    u32 rx_pointer, u32 tx_pointer)
{
  stream_session_t *s;
  s = session_get (tc->s_index, tc->thread_index);
  svm_fifo_init_pointers (s->server_rx_fifo, rx_pointer);
  svm_fifo_init_pointers (s->server_tx_fifo, tx_pointer);
}

int
session_stream_connect_notify (transport_connection_t * tc, u8 is_fail)
{
  application_t *app;
  stream_session_t *new_s = 0;
  u64 handle;
  u32 opaque = 0;
  int error = 0;
  segment_manager_t *sm;
  u8 alloc_fifos;

  /*
   * Find connection handle and cleanup half-open table
   */
  handle = session_lookup_half_open_handle (tc);
  if (handle == HALF_OPEN_LOOKUP_INVALID_VALUE)
    {
      SESSION_DBG ("half-open was removed!");
      return -1;
    }
  session_lookup_del_half_open (tc);

  /* Get the app's index from the handle we stored when opening connection
   * and the opaque (api_context for external apps) from transport session
   * index */
  app = application_get_if_valid (handle >> 32);
  if (!app)
    return -1;
  opaque = tc->s_index;

  /*
   * Allocate new session with fifos (svm segments are allocated if needed)
   */
  if (!is_fail)
    {
      sm = application_get_connect_segment_manager (app);
      alloc_fifos = application_is_proxy (app);
      if (session_alloc_and_init (sm, tc, alloc_fifos, &new_s))
	{
	  is_fail = 1;
	  error = -1;
	}
      else
	new_s->app_index = app->index;
    }

  /*
   * Notify client application
   */
  if (app->cb_fns.session_connected_callback (app->index, opaque, new_s,
					      is_fail))
    {
      SESSION_DBG ("failed to notify app");
      if (!is_fail)
	stream_session_disconnect (new_s);
    }
  else
    {
      if (!is_fail)
	new_s->session_state = SESSION_STATE_READY;
    }

  return error;
}

typedef struct _session_switch_pool_args
{
  u32 session_index;
  u32 thread_index;
  u32 new_thread_index;
  u32 new_session_index;
} session_switch_pool_args_t;

static void
session_switch_pool (void *cb_args)
{
  session_switch_pool_args_t *args = (session_switch_pool_args_t *) cb_args;
  stream_session_t *s;
  ASSERT (args->thread_index == vlib_get_thread_index ());
  s = session_get (args->session_index, args->thread_index);
  s->server_tx_fifo->master_session_index = args->new_session_index;
  s->server_tx_fifo->master_thread_index = args->new_thread_index;
  tp_vfts[s->session_type].cleanup (s->connection_index, s->thread_index);
  session_free (s);
  clib_mem_free (cb_args);
}

/**
 * Move dgram session to the right thread
 */
int
session_dgram_connect_notify (transport_connection_t * tc,
			      u32 old_thread_index,
			      stream_session_t ** new_session)
{
  stream_session_t *new_s;
  session_switch_pool_args_t *rpc_args;

  /*
   * Clone half-open session to the right thread.
   */
  new_s = session_clone_safe (tc->s_index, old_thread_index);
  new_s->connection_index = tc->c_index;
  new_s->server_rx_fifo->master_session_index = new_s->session_index;
  new_s->server_rx_fifo->master_thread_index = new_s->thread_index;
  new_s->session_state = SESSION_STATE_READY;
  session_lookup_add_connection (tc, session_handle (new_s));

  /*
   * Ask thread owning the old session to clean it up and make us the tx
   * fifo owner
   */
  rpc_args = clib_mem_alloc (sizeof (*rpc_args));
  rpc_args->new_session_index = new_s->session_index;
  rpc_args->new_thread_index = new_s->thread_index;
  rpc_args->session_index = tc->s_index;
  rpc_args->thread_index = old_thread_index;
  session_send_rpc_evt_to_thread (rpc_args->thread_index, session_switch_pool,
				  rpc_args);

  tc->s_index = new_s->session_index;
  new_s->connection_index = tc->c_index;
  *new_session = new_s;
  return 0;
}

void
stream_session_accept_notify (transport_connection_t * tc)
{
  application_t *server;
  stream_session_t *s;

  s = session_get (tc->s_index, tc->thread_index);
  server = application_get (s->app_index);
  server->cb_fns.session_accept_callback (s);
}

/**
 * Notification from transport that connection is being closed.
 *
 * A disconnect is sent to application but state is not removed. Once
 * disconnect is acknowledged by application, session disconnect is called.
 * Ultimately this leads to close being called on transport (passive close).
 */
void
stream_session_disconnect_notify (transport_connection_t * tc)
{
  application_t *server;
  stream_session_t *s;

  s = session_get (tc->s_index, tc->thread_index);
  server = application_get (s->app_index);
  server->cb_fns.session_disconnect_callback (s);
}

/**
 * Cleans up session and lookup table.
 */
void
stream_session_delete (stream_session_t * s)
{
  int rv;

  /* Delete from the main lookup table. */
  if ((rv = session_lookup_del_session (s)))
    clib_warning ("hash delete error, rv %d", rv);

  /* Cleanup fifo segments */
  segment_manager_dealloc_fifos (s->svm_segment_index, s->server_rx_fifo,
				 s->server_tx_fifo);
  session_free (s);
}

/**
 * Notification from transport that connection is being deleted
 *
 * This removes the session if it is still valid. It should be called only on
 * previously fully established sessions. For instance failed connects should
 * call stream_session_connect_notify and indicate that the connect has
 * failed.
 */
void
stream_session_delete_notify (transport_connection_t * tc)
{
  stream_session_t *s;

  /* App might've been removed already */
  s = session_get_if_valid (tc->s_index, tc->thread_index);
  if (!s)
    return;
  stream_session_delete (s);
}

/**
 * Notify application that connection has been reset.
 */
void
stream_session_reset_notify (transport_connection_t * tc)
{
  stream_session_t *s;
  application_t *app;
  s = session_get (tc->s_index, tc->thread_index);

  app = application_get (s->app_index);
  app->cb_fns.session_reset_callback (s);
}

/**
 * Accept a stream session. Optionally ping the server by callback.
 */
int
stream_session_accept (transport_connection_t * tc, u32 listener_index,
		       u8 notify)
{
  application_t *server;
  stream_session_t *s, *listener;
  segment_manager_t *sm;
  session_type_t sst;
  int rv;

  sst = session_type_from_proto_and_ip (tc->proto, tc->is_ip4);

  /* Find the server */
  listener = listen_session_get (sst, listener_index);
  server = application_get (listener->app_index);

  sm = application_get_listen_segment_manager (server, listener);
  if ((rv = session_alloc_and_init (sm, tc, 1, &s)))
    return rv;

  s->app_index = server->index;
  s->listener_index = listener_index;
  s->session_state = SESSION_STATE_ACCEPTING;

  /* Shoulder-tap the server */
  if (notify)
    {
      server->cb_fns.session_accept_callback (s);
    }

  return 0;
}

/**
 * Ask transport to open connection to remote transport endpoint.
 *
 * Stores handle for matching request with reply since the call can be
 * asynchronous. For instance, for TCP the 3-way handshake must complete
 * before reply comes. Session is only created once connection is established.
 *
 * @param app_index Index of the application requesting the connect
 * @param st Session type requested.
 * @param tep Remote transport endpoint
 * @param opaque Opaque data (typically, api_context) the application expects
 * 		 on open completion.
 */
int
session_open (u32 app_index, session_endpoint_t * rmt, u32 opaque)
{
  transport_connection_t *tc;
  session_type_t sst;
  segment_manager_t *sm;
  stream_session_t *s;
  application_t *app;
  int rv;
  u64 handle;

  sst = session_type_from_proto_and_ip (rmt->transport_proto, rmt->is_ip4);
  rv = tp_vfts[sst].open (session_endpoint_to_transport (rmt));
  if (rv < 0)
    {
      SESSION_DBG ("Transport failed to open connection.");
      return VNET_API_ERROR_SESSION_CONNECT;
    }

  tc = tp_vfts[sst].get_half_open ((u32) rv);

  /* If transport offers a stream service, only allocate session once the
   * connection has been established.
   */
  if (transport_is_stream (rmt->transport_proto))
    {
      /* Add connection to half-open table and save app and tc index. The
       * latter is needed to help establish the connection while the former
       * is needed when the connect notify comes and we have to notify the
       * external app
       */
      handle = (((u64) app_index) << 32) | (u64) tc->c_index;
      session_lookup_add_half_open (tc, handle);

      /* Store api_context (opaque) for when the reply comes. Not the nicest
       * thing but better than allocating a separate half-open pool.
       */
      tc->s_index = opaque;
    }
  /* For dgram type of service, allocate session and fifos now.
   */
  else
    {
      app = application_get (app_index);
      sm = application_get_connect_segment_manager (app);

      if (session_alloc_and_init (sm, tc, 1, &s))
	return -1;
      s->app_index = app->index;
      s->session_state = SESSION_STATE_CONNECTING_READY;

      /* Tell the app about the new event fifo for this session */
      app->cb_fns.session_connected_callback (app->index, opaque, s, 0);
    }
  return 0;
}

/**
 * Ask transport to listen on local transport endpoint.
 *
 * @param s Session for which listen will be called. Note that unlike
 * 	    established sessions, listen sessions are not associated to a
 * 	    thread.
 * @param tep Local endpoint to be listened on.
 */
int
stream_session_listen (stream_session_t * s, session_endpoint_t * sep)
{
  transport_connection_t *tc;
  u32 tci;

  /* Transport bind/listen  */
  tci = tp_vfts[s->session_type].bind (s->session_index,
				       session_endpoint_to_transport (sep));

  if (tci == (u32) ~ 0)
    return -1;

  /* Attach transport to session */
  s->connection_index = tci;
  tc = tp_vfts[s->session_type].get_listener (tci);

  /* Weird but handle it ... */
  if (tc == 0)
    return -1;

  /* Add to the main lookup table */
  session_lookup_add_connection (tc, s->session_index);
  return 0;
}

/**
 * Ask transport to stop listening on local transport endpoint.
 *
 * @param s Session to stop listening on. It must be in state LISTENING.
 */
int
stream_session_stop_listen (stream_session_t * s)
{
  transport_connection_t *tc;

  if (s->session_state != SESSION_STATE_LISTENING)
    {
      clib_warning ("not a listening session");
      return -1;
    }

  tc = tp_vfts[s->session_type].get_listener (s->connection_index);
  if (!tc)
    {
      clib_warning ("no transport");
      return VNET_API_ERROR_ADDRESS_NOT_IN_USE;
    }

  session_lookup_del_connection (tc);
  tp_vfts[s->session_type].unbind (s->connection_index);
  return 0;
}

/**
 * Disconnect session and propagate to transport. This should eventually
 * result in a delete notification that allows us to cleanup session state.
 * Called for both active/passive disconnects.
 *
 * Should be called from the session's thread.
 */
void
stream_session_disconnect (stream_session_t * s)
{
  s->session_state = SESSION_STATE_CLOSED;
  tp_vfts[s->session_type].close (s->connection_index, s->thread_index);
}

/**
 * Cleanup transport and session state.
 *
 * Notify transport of the cleanup, wait for a delete notify to actually
 * remove the session state.
 */
void
stream_session_cleanup (stream_session_t * s)
{
  int rv;

  s->session_state = SESSION_STATE_CLOSED;

  /* Delete from the main lookup table to avoid more enqueues */
  rv = session_lookup_del_session (s);
  if (rv)
    clib_warning ("hash delete error, rv %d", rv);

  tp_vfts[s->session_type].cleanup (s->connection_index, s->thread_index);
}

/**
 * Allocate vpp event queue (once) per worker thread
 */
void
session_vpp_event_queue_allocate (session_manager_main_t * smm,
				  u32 thread_index)
{
  api_main_t *am = &api_main;
  void *oldheap;
  u32 event_queue_length = 2048;

  if (smm->vpp_event_queues[thread_index] == 0)
    {
      /* Allocate event fifo in the /vpe-api shared-memory segment */
      oldheap = svm_push_data_heap (am->vlib_rp);

      if (smm->configured_event_queue_length)
	event_queue_length = smm->configured_event_queue_length;

      smm->vpp_event_queues[thread_index] =
	unix_shared_memory_queue_init
	(event_queue_length,
	 sizeof (session_fifo_event_t), 0 /* consumer pid */ ,
	 0 /* (do not) send signal when queue non-empty */ );

      svm_pop_heap (oldheap);
    }
}

session_type_t
session_type_from_proto_and_ip (transport_proto_t proto, u8 is_ip4)
{
  if (proto == TRANSPORT_PROTO_TCP)
    {
      if (is_ip4)
	return SESSION_TYPE_IP4_TCP;
      else
	return SESSION_TYPE_IP6_TCP;
    }
  else
    {
      if (is_ip4)
	return SESSION_TYPE_IP4_UDP;
      else
	return SESSION_TYPE_IP6_UDP;
    }

  return SESSION_N_TYPES;
}

transport_connection_t *
session_get_transport (stream_session_t * s)
{
  if (s->session_state != SESSION_STATE_LISTENING)
    return tp_vfts[s->session_type].get_connection (s->connection_index,
						    s->thread_index);
  return 0;
}

transport_connection_t *
listen_session_get_transport (stream_session_t * s)
{
  return tp_vfts[s->session_type].get_listener (s->connection_index);
}

int
listen_session_get_local_session_endpoint (stream_session_t * listener,
					   session_endpoint_t * sep)
{
  transport_connection_t *tc;
  tc =
    tp_vfts[listener->session_type].get_listener (listener->connection_index);
  if (!tc)
    {
      clib_warning ("no transport");
      return -1;
    }

  /* N.B. The ip should not be copied because this is the local endpoint */
  sep->port = tc->lcl_port;
  sep->transport_proto = tc->proto;
  sep->is_ip4 = tc->is_ip4;
  return 0;
}

static clib_error_t *
session_manager_main_enable (vlib_main_t * vm)
{
  session_manager_main_t *smm = &session_manager_main;
  vlib_thread_main_t *vtm = vlib_get_thread_main ();
  u32 num_threads;
  u32 preallocated_sessions_per_worker;
  int i, j;

  num_threads = 1 /* main thread */  + vtm->n_threads;

  if (num_threads < 1)
    return clib_error_return (0, "n_thread_stacks not set");

  /* $$$ config parameters */
  svm_fifo_segment_init (0x200000000ULL /* first segment base VA */ ,
			 20 /* timeout in seconds */ );

  /* configure per-thread ** vectors */
  vec_validate (smm->sessions, num_threads - 1);
  vec_validate (smm->tx_buffers, num_threads - 1);
  vec_validate (smm->pending_event_vector, num_threads - 1);
  vec_validate (smm->pending_disconnects, num_threads - 1);
  vec_validate (smm->free_event_vector, num_threads - 1);
  vec_validate (smm->vpp_event_queues, num_threads - 1);
  vec_validate (smm->session_peekers, num_threads - 1);
  vec_validate (smm->peekers_readers_locks, num_threads - 1);
  vec_validate (smm->peekers_write_locks, num_threads - 1);

  for (i = 0; i < TRANSPORT_N_PROTO; i++)
    for (j = 0; j < num_threads; j++)
      {
	vec_validate (smm->session_to_enqueue[i], num_threads - 1);
	vec_validate (smm->current_enqueue_epoch[i], num_threads - 1);
      }

  for (i = 0; i < num_threads; i++)
    {
      vec_validate (smm->free_event_vector[i], 0);
      _vec_len (smm->free_event_vector[i]) = 0;
      vec_validate (smm->pending_event_vector[i], 0);
      _vec_len (smm->pending_event_vector[i]) = 0;
      vec_validate (smm->pending_disconnects[i], 0);
      _vec_len (smm->pending_disconnects[i]) = 0;
    }

#if SESSION_DBG
  vec_validate (smm->last_event_poll_by_thread, num_threads - 1);
#endif

  /* Allocate vpp event queues */
  for (i = 0; i < vec_len (smm->vpp_event_queues); i++)
    session_vpp_event_queue_allocate (smm, i);

  /* Preallocate sessions */
  if (smm->preallocated_sessions)
    {
      if (num_threads == 1)
	{
	  pool_init_fixed (smm->sessions[0], smm->preallocated_sessions);
	}
      else
	{
	  int j;
	  preallocated_sessions_per_worker =
	    (1.1 * (f64) smm->preallocated_sessions /
	     (f64) (num_threads - 1));

	  for (j = 1; j < num_threads; j++)
	    {
	      pool_init_fixed (smm->sessions[j],
			       preallocated_sessions_per_worker);
	    }
	}
    }

  session_lookup_init ();
  app_namespaces_init ();
  transport_init ();

  smm->is_enabled = 1;

  /* Enable TCP transport */
  vnet_tcp_enable_disable (vm, 1);

  return 0;
}

void
session_node_enable_disable (u8 is_en)
{
  u8 state = is_en ? VLIB_NODE_STATE_POLLING : VLIB_NODE_STATE_DISABLED;
  /* *INDENT-OFF* */
  foreach_vlib_main (({
    vlib_node_set_state (this_vlib_main, session_queue_node.index,
                         state);
  }));
  /* *INDENT-ON* */
}

clib_error_t *
vnet_session_enable_disable (vlib_main_t * vm, u8 is_en)
{
  clib_error_t *error = 0;
  if (is_en)
    {
      if (session_manager_main.is_enabled)
	return 0;

      session_node_enable_disable (is_en);
      error = session_manager_main_enable (vm);
    }
  else
    {
      session_manager_main.is_enabled = 0;
      session_node_enable_disable (is_en);
    }

  return error;
}

clib_error_t *
session_manager_main_init (vlib_main_t * vm)
{
  session_manager_main_t *smm = &session_manager_main;
  smm->is_enabled = 0;
  return 0;
}

VLIB_INIT_FUNCTION (session_manager_main_init);

static clib_error_t *
session_config_fn (vlib_main_t * vm, unformat_input_t * input)
{
  session_manager_main_t *smm = &session_manager_main;
  u32 nitems;
  uword tmp;

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "event-queue-length %d", &nitems))
	{
	  if (nitems >= 2048)
	    smm->configured_event_queue_length = nitems;
	  else
	    clib_warning ("event queue length %d too small, ignored", nitems);
	}
      else if (unformat (input, "preallocated-sessions %d",
			 &smm->preallocated_sessions))
	;
      else if (unformat (input, "v4-session-table-buckets %d",
			 &smm->configured_v4_session_table_buckets))
	;
      else if (unformat (input, "v4-halfopen-table-buckets %d",
			 &smm->configured_v4_halfopen_table_buckets))
	;
      else if (unformat (input, "v6-session-table-buckets %d",
			 &smm->configured_v6_session_table_buckets))
	;
      else if (unformat (input, "v6-halfopen-table-buckets %d",
			 &smm->configured_v6_halfopen_table_buckets))
	;
      else if (unformat (input, "v4-session-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v4_session_table_memory = tmp;
	}
      else if (unformat (input, "v4-halfopen-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v4_halfopen_table_memory = tmp;
	}
      else if (unformat (input, "v6-session-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v6_session_table_memory = tmp;
	}
      else if (unformat (input, "v6-halfopen-table-memory %U",
			 unformat_memory_size, &tmp))
	{
	  if (tmp >= 0x100000000)
	    return clib_error_return (0, "memory size %llx (%lld) too large",
				      tmp, tmp);
	  smm->configured_v6_halfopen_table_memory = tmp;
	}
      else
	return clib_error_return (0, "unknown input `%U'",
				  format_unformat_error, input);
    }
  return 0;
}

VLIB_CONFIG_FUNCTION (session_config_fn, "session");

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */