1 /* 2 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. 3 */ 4 5 /* 6 * This file contains code imported from the OFED rds source file connection.c 7 * Oracle elects to have and use the contents of connection.c under and governed 8 * by the OpenIB.org BSD license (see below for full license text). However, 9 * the following notice accompanied the original version of this file: 10 */ 11 12 /* 13 * Copyright (c) 2006 Oracle. All rights reserved. 14 * 15 * This software is available to you under a choice of one of two 16 * licenses. You may choose to be licensed under the terms of the GNU 17 * General Public License (GPL) Version 2, available from the file 18 * COPYING in the main directory of this source tree, or the 19 * OpenIB.org BSD license below: 20 * 21 * Redistribution and use in source and binary forms, with or 22 * without modification, are permitted provided that the following 23 * conditions are met: 24 * 25 * - Redistributions of source code must retain the above 26 * copyright notice, this list of conditions and the following 27 * disclaimer. 28 * 29 * - Redistributions in binary form must reproduce the above 30 * copyright notice, this list of conditions and the following 31 * disclaimer in the documentation and/or other materials 32 * provided with the distribution. 33 * 34 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 35 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 36 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 37 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 38 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 39 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 40 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 41 * SOFTWARE. 42 * 43 */ 44 #include <sys/types.h> 45 #include <sys/kmem.h> 46 #include <sys/rds.h> 47 48 #include <sys/ib/clients/rdsv3/rdsv3.h> 49 #include <sys/ib/clients/rdsv3/loop.h> 50 #include <sys/ib/clients/rdsv3/rdsv3_debug.h> 51 52 /* converting this to RCU is a chore for another day.. */ 53 static krwlock_t rdsv3_conn_lock; 54 struct avl_tree rdsv3_conn_hash; 55 static struct kmem_cache *rdsv3_conn_slab = NULL; 56 57 #define rdsv3_conn_info_set(var, test, suffix) do { \ 58 if (test) \ 59 var |= RDS_INFO_CONNECTION_FLAG_##suffix; \ 60 } while (0) 61 62 63 static struct rdsv3_connection * 64 rdsv3_conn_lookup(uint32_be_t laddr, uint32_be_t faddr, avl_index_t *pos) 65 { 66 struct rdsv3_connection *conn; 67 struct rdsv3_conn_info_s conn_info; 68 avl_index_t place = 0; 69 70 conn_info.c_laddr = laddr; 71 conn_info.c_faddr = faddr; 72 73 conn = avl_find(&rdsv3_conn_hash, &conn_info, &place); 74 75 RDSV3_DPRINTF5("rdsv3_conn_lookup", 76 "returning conn %p for %u.%u.%u.%u -> %u.%u.%u.%u", 77 conn, NIPQUAD(laddr), NIPQUAD(faddr)); 78 79 if (pos != NULL) 80 *pos = place; 81 82 return (conn); 83 } 84 85 /* 86 * This is called by transports as they're bringing down a connection. 87 * It clears partial message state so that the transport can start sending 88 * and receiving over this connection again in the future. It is up to 89 * the transport to have serialized this call with its send and recv. 90 */ 91 void 92 rdsv3_conn_reset(struct rdsv3_connection *conn) 93 { 94 RDSV3_DPRINTF2("rdsv3_conn_reset", 95 "connection %u.%u.%u.%u to %u.%u.%u.%u reset", 96 NIPQUAD(conn->c_laddr), NIPQUAD(conn->c_faddr)); 97 98 rdsv3_stats_inc(s_conn_reset); 99 rdsv3_send_reset(conn); 100 conn->c_flags = 0; 101 102 /* 103 * Do not clear next_rx_seq here, else we cannot distinguish 104 * retransmitted packets from new packets, and will hand all 105 * of them to the application. That is not consistent with the 106 * reliability guarantees of RDS. 107 */ 108 } 109 110 /* 111 * There is only every one 'conn' for a given pair of addresses in the 112 * system at a time. They contain messages to be retransmitted and so 113 * span the lifetime of the actual underlying transport connections. 114 * 115 * For now they are not garbage collected once they're created. They 116 * are torn down as the module is removed, if ever. 117 */ 118 static struct rdsv3_connection * 119 __rdsv3_conn_create(uint32_be_t laddr, uint32_be_t faddr, 120 struct rdsv3_transport *trans, int gfp, int is_outgoing) 121 { 122 struct rdsv3_connection *conn, *parent = NULL; 123 avl_index_t pos; 124 int ret; 125 126 rw_enter(&rdsv3_conn_lock, RW_READER); 127 conn = rdsv3_conn_lookup(laddr, faddr, &pos); 128 if (conn && 129 conn->c_loopback && 130 conn->c_trans != &rdsv3_loop_transport && 131 !is_outgoing) { 132 /* 133 * This is a looped back IB connection, and we're 134 * called by the code handling the incoming connect. 135 * We need a second connection object into which we 136 * can stick the other QP. 137 */ 138 parent = conn; 139 conn = parent->c_passive; 140 } 141 rw_exit(&rdsv3_conn_lock); 142 if (conn) 143 goto out; 144 145 RDSV3_DPRINTF2("__rdsv3_conn_create", "Enter(%x -> %x)", 146 ntohl(laddr), ntohl(faddr)); 147 148 conn = kmem_cache_alloc(rdsv3_conn_slab, gfp); 149 if (!conn) { 150 conn = ERR_PTR(-ENOMEM); 151 goto out; 152 } 153 154 /* see rdsv3_conn_constructor */ 155 conn->c_laddr = laddr; 156 conn->c_faddr = faddr; 157 158 /* 159 * We don't allow sockets to send messages without binding. 160 * So, the IP address will already be there in the bind array. 161 * Mostly, this is a readonly operation. 162 * For now, passing GLOBAL_ZONEID. 163 */ 164 conn->c_bucketp = rdsv3_find_ip_bucket(ntohl(laddr), GLOBAL_ZONEID); 165 166 ret = rdsv3_cong_get_maps(conn); 167 if (ret) { 168 kmem_cache_free(rdsv3_conn_slab, conn); 169 conn = ERR_PTR(ret); 170 goto out; 171 } 172 173 /* 174 * This is where a connection becomes loopback. If *any* RDS sockets 175 * can bind to the destination address then we'd rather the messages 176 * flow through loopback rather than either transport. 177 */ 178 if (rdsv3_trans_get_preferred(faddr)) { 179 conn->c_loopback = 1; 180 if (is_outgoing && trans->t_prefer_loopback) { 181 /* 182 * "outgoing" connection - and the transport 183 * says it wants the connection handled by the 184 * loopback transport. This is what TCP does. 185 */ 186 trans = &rdsv3_loop_transport; 187 } 188 } 189 190 conn->c_trans = trans; 191 192 ret = trans->conn_alloc(conn, gfp); 193 if (ret) { 194 kmem_cache_free(rdsv3_conn_slab, conn); 195 conn = ERR_PTR(ret); 196 goto out; 197 } 198 199 conn->c_state = RDSV3_CONN_DOWN; 200 conn->c_reconnect_jiffies = 0; 201 RDSV3_INIT_DELAYED_WORK(&conn->c_send_w, rdsv3_send_worker); 202 RDSV3_INIT_DELAYED_WORK(&conn->c_recv_w, rdsv3_recv_worker); 203 RDSV3_INIT_DELAYED_WORK(&conn->c_conn_w, rdsv3_connect_worker); 204 RDSV3_INIT_DELAYED_WORK(&conn->c_reap_w, rdsv3_reaper_worker); 205 RDSV3_INIT_WORK(&conn->c_down_w, rdsv3_shutdown_worker); 206 mutex_init(&conn->c_cm_lock, NULL, MUTEX_DRIVER, NULL); 207 conn->c_flags = 0; 208 209 RDSV3_DPRINTF2("__rdsv3_conn_create", 210 "allocated conn %p for %u.%u.%u.%u -> %u.%u.%u.%u over %s %s", 211 conn, NIPQUAD(laddr), NIPQUAD(faddr), 212 trans->t_name ? trans->t_name : "[unknown]", 213 is_outgoing ? "(outgoing)" : ""); 214 215 /* 216 * Since we ran without holding the conn lock, someone could 217 * have created the same conn (either normal or passive) in the 218 * interim. We check while holding the lock. If we won, we complete 219 * init and return our conn. If we lost, we rollback and return the 220 * other one. 221 */ 222 rw_enter(&rdsv3_conn_lock, RW_WRITER); 223 if (parent) { 224 /* Creating passive conn */ 225 if (parent->c_passive) { 226 trans->conn_free(conn->c_transport_data); 227 kmem_cache_free(rdsv3_conn_slab, conn); 228 conn = parent->c_passive; 229 } else { 230 parent->c_passive = conn; 231 rdsv3_cong_add_conn(conn); 232 } 233 } else { 234 /* Creating normal conn */ 235 struct rdsv3_connection *found; 236 237 found = rdsv3_conn_lookup(laddr, faddr, &pos); 238 if (found) { 239 trans->conn_free(conn->c_transport_data); 240 kmem_cache_free(rdsv3_conn_slab, conn); 241 conn = found; 242 } else { 243 avl_insert(&rdsv3_conn_hash, conn, pos); 244 rdsv3_cong_add_conn(conn); 245 rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_reap_w, 246 RDSV3_REAPER_WAIT_JIFFIES); 247 } 248 } 249 250 rw_exit(&rdsv3_conn_lock); 251 252 RDSV3_DPRINTF2("__rdsv3_conn_create", "Return(conn: %p)", conn); 253 254 out: 255 return (conn); 256 } 257 258 struct rdsv3_connection * 259 rdsv3_conn_create(uint32_be_t laddr, uint32_be_t faddr, 260 struct rdsv3_transport *trans, int gfp) 261 { 262 return (__rdsv3_conn_create(laddr, faddr, trans, gfp, 0)); 263 } 264 265 struct rdsv3_connection * 266 rdsv3_conn_create_outgoing(uint32_be_t laddr, uint32_be_t faddr, 267 struct rdsv3_transport *trans, int gfp) 268 { 269 return (__rdsv3_conn_create(laddr, faddr, trans, gfp, 1)); 270 } 271 272 extern struct avl_tree rdsv3_conn_hash; 273 274 void 275 rdsv3_conn_shutdown(struct rdsv3_connection *conn) 276 { 277 RDSV3_DPRINTF2("rdsv3_conn_shutdown", "Enter(conn: %p)", conn); 278 279 /* shut it down unless it's down already */ 280 if (!rdsv3_conn_transition(conn, RDSV3_CONN_DOWN, RDSV3_CONN_DOWN)) { 281 /* 282 * Quiesce the connection mgmt handlers before we start tearing 283 * things down. We don't hold the mutex for the entire 284 * duration of the shutdown operation, else we may be 285 * deadlocking with the CM handler. Instead, the CM event 286 * handler is supposed to check for state DISCONNECTING 287 */ 288 mutex_enter(&conn->c_cm_lock); 289 if (!rdsv3_conn_transition(conn, RDSV3_CONN_UP, 290 RDSV3_CONN_DISCONNECTING) && 291 !rdsv3_conn_transition(conn, RDSV3_CONN_ERROR, 292 RDSV3_CONN_DISCONNECTING)) { 293 RDSV3_DPRINTF2("rdsv3_conn_shutdown", 294 "shutdown called in state %d", 295 atomic_get(&conn->c_state)); 296 rdsv3_conn_drop(conn); 297 mutex_exit(&conn->c_cm_lock); 298 return; 299 } 300 mutex_exit(&conn->c_cm_lock); 301 302 /* verify everybody's out of rds_send_xmit() */ 303 mutex_enter(&conn->c_send_lock); 304 while (atomic_get(&conn->c_senders)) { 305 mutex_exit(&conn->c_send_lock); 306 delay(1); 307 mutex_enter(&conn->c_send_lock); 308 } 309 310 conn->c_trans->conn_shutdown(conn); 311 rdsv3_conn_reset(conn); 312 mutex_exit(&conn->c_send_lock); 313 314 if (!rdsv3_conn_transition(conn, RDSV3_CONN_DISCONNECTING, 315 RDSV3_CONN_DOWN)) { 316 /* 317 * This can happen - eg when we're in the middle of 318 * tearing down the connection, and someone unloads 319 * the rds module. 320 * Quite reproduceable with loopback connections. 321 * Mostly harmless. 322 */ 323 #ifndef __lock_lint 324 RDSV3_DPRINTF2("rdsv3_conn_shutdown", 325 "failed to transition to state DOWN, " 326 "current statis is: %d", 327 atomic_get(&conn->c_state)); 328 rdsv3_conn_drop(conn); 329 #endif 330 return; 331 } 332 } 333 334 /* 335 * Then reconnect if it's still live. 336 * The passive side of an IB loopback connection is never added 337 * to the conn hash, so we never trigger a reconnect on this 338 * conn - the reconnect is always triggered by the active peer. 339 */ 340 rdsv3_cancel_delayed_work(&conn->c_conn_w); 341 342 { 343 struct rdsv3_conn_info_s conn_info; 344 345 conn_info.c_laddr = conn->c_laddr; 346 conn_info.c_faddr = conn->c_faddr; 347 if (avl_find(&rdsv3_conn_hash, &conn_info, NULL) == conn) 348 rdsv3_queue_reconnect(conn); 349 } 350 RDSV3_DPRINTF2("rdsv3_conn_shutdown", "Exit"); 351 } 352 353 /* 354 * Stop and free a connection. 355 */ 356 void 357 rdsv3_conn_destroy(struct rdsv3_connection *conn) 358 { 359 struct rdsv3_message *rm, *rtmp; 360 list_t to_be_dropped; 361 362 RDSV3_DPRINTF4("rdsv3_conn_destroy", 363 "freeing conn %p for %u.%u.%u.%u -> %u.%u.%u.%u", 364 conn, NIPQUAD(conn->c_laddr), NIPQUAD(conn->c_faddr)); 365 366 avl_remove(&rdsv3_conn_hash, conn); 367 368 rdsv3_cancel_delayed_work(&conn->c_reap_w); 369 rdsv3_cancel_delayed_work(&conn->c_send_w); 370 rdsv3_cancel_delayed_work(&conn->c_recv_w); 371 372 rdsv3_conn_shutdown(conn); 373 374 /* tear down queued messages */ 375 376 list_create(&to_be_dropped, sizeof (struct rdsv3_message), 377 offsetof(struct rdsv3_message, m_conn_item)); 378 379 RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, rtmp, &conn->c_retrans, m_conn_item) { 380 list_remove_node(&rm->m_conn_item); 381 list_insert_tail(&to_be_dropped, rm); 382 } 383 384 RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, rtmp, &conn->c_send_queue, 385 m_conn_item) { 386 list_remove_node(&rm->m_conn_item); 387 list_insert_tail(&to_be_dropped, rm); 388 } 389 390 RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, rtmp, &to_be_dropped, m_conn_item) { 391 clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags); 392 list_remove_node(&rm->m_conn_item); 393 rdsv3_message_put(rm); 394 } 395 396 if (conn->c_xmit_rm) 397 rdsv3_message_put(conn->c_xmit_rm); 398 399 conn->c_trans->conn_free(conn->c_transport_data); 400 401 /* 402 * The congestion maps aren't freed up here. They're 403 * freed by rdsv3_cong_exit() after all the connections 404 * have been freed. 405 */ 406 rdsv3_cong_remove_conn(conn); 407 408 ASSERT(list_is_empty(&conn->c_retrans)); 409 kmem_cache_free(rdsv3_conn_slab, conn); 410 411 } 412 413 /* ARGSUSED */ 414 static void 415 rdsv3_conn_message_info(struct rsock *sock, unsigned int len, 416 struct rdsv3_info_iterator *iter, 417 struct rdsv3_info_lengths *lens, 418 int want_send) 419 { 420 struct list *list; 421 struct rdsv3_connection *conn; 422 struct rdsv3_message *rm; 423 unsigned int total = 0; 424 425 RDSV3_DPRINTF4("rdsv3_conn_message_info", "Enter"); 426 427 len /= sizeof (struct rds_info_message); 428 429 rw_enter(&rdsv3_conn_lock, RW_READER); 430 431 if (avl_is_empty(&rdsv3_conn_hash)) { 432 /* no connections */ 433 rw_exit(&rdsv3_conn_lock); 434 return; 435 } 436 437 conn = (struct rdsv3_connection *)avl_first(&rdsv3_conn_hash); 438 439 do { 440 if (want_send) 441 list = &conn->c_send_queue; 442 else 443 list = &conn->c_retrans; 444 445 mutex_enter(&conn->c_lock); 446 447 /* XXX too lazy to maintain counts.. */ 448 RDSV3_FOR_EACH_LIST_NODE(rm, list, m_conn_item) { 449 total++; 450 if (total <= len) 451 rdsv3_inc_info_copy(&rm->m_inc, iter, 452 conn->c_laddr, conn->c_faddr, 0); 453 } 454 455 mutex_exit(&conn->c_lock); 456 457 conn = AVL_NEXT(&rdsv3_conn_hash, conn); 458 } while (conn != NULL); 459 rw_exit(&rdsv3_conn_lock); 460 461 lens->nr = total; 462 lens->each = sizeof (struct rds_info_message); 463 464 RDSV3_DPRINTF4("rdsv3_conn_message_info", "Return"); 465 } 466 467 static void 468 rdsv3_conn_message_info_send(struct rsock *sock, unsigned int len, 469 struct rdsv3_info_iterator *iter, 470 struct rdsv3_info_lengths *lens) 471 { 472 rdsv3_conn_message_info(sock, len, iter, lens, 1); 473 } 474 475 static void 476 rdsv3_conn_message_info_retrans(struct rsock *sock, 477 unsigned int len, 478 struct rdsv3_info_iterator *iter, 479 struct rdsv3_info_lengths *lens) 480 { 481 rdsv3_conn_message_info(sock, len, iter, lens, 0); 482 } 483 484 /* ARGSUSED */ 485 void 486 rdsv3_for_each_conn_info(struct rsock *sock, unsigned int len, 487 struct rdsv3_info_iterator *iter, 488 struct rdsv3_info_lengths *lens, 489 int (*visitor)(struct rdsv3_connection *, void *), 490 size_t item_len) 491 { 492 uint8_t *buffer; 493 struct rdsv3_connection *conn; 494 495 rw_enter(&rdsv3_conn_lock, RW_READER); 496 497 lens->nr = 0; 498 lens->each = item_len; 499 500 if (avl_is_empty(&rdsv3_conn_hash)) { 501 /* no connections */ 502 rw_exit(&rdsv3_conn_lock); 503 return; 504 } 505 506 /* allocate a little extra as this can get cast to a uint64_t */ 507 buffer = kmem_zalloc(item_len + 8, KM_SLEEP); 508 509 conn = (struct rdsv3_connection *)avl_first(&rdsv3_conn_hash); 510 511 do { 512 /* XXX no c_lock usage.. */ 513 if (visitor(conn, buffer)) { 514 /* 515 * We copy as much as we can fit in the buffer, 516 * but we count all items so that the caller 517 * can resize the buffer. 518 */ 519 if (len >= item_len) { 520 RDSV3_DPRINTF4("rdsv3_for_each_conn_info", 521 "buffer: %p iter: %p bytes: %d", buffer, 522 iter->addr + iter->offset, item_len); 523 rdsv3_info_copy(iter, buffer, item_len); 524 len -= item_len; 525 } 526 lens->nr++; 527 } 528 conn = AVL_NEXT(&rdsv3_conn_hash, conn); 529 } while (conn != NULL); 530 rw_exit(&rdsv3_conn_lock); 531 532 kmem_free(buffer, item_len + 8); 533 } 534 535 static int 536 rdsv3_conn_info_visitor(struct rdsv3_connection *conn, void *buffer) 537 { 538 struct rds_info_connection *cinfo = buffer; 539 540 cinfo->next_tx_seq = conn->c_next_tx_seq; 541 cinfo->next_rx_seq = conn->c_next_rx_seq; 542 cinfo->laddr = conn->c_laddr; 543 cinfo->faddr = conn->c_faddr; 544 (void) strncpy((char *)cinfo->transport, conn->c_trans->t_name, 545 sizeof (cinfo->transport)); 546 cinfo->flags = 0; 547 548 rdsv3_conn_info_set(cinfo->flags, 549 MUTEX_HELD(&conn->c_send_lock), SENDING); 550 551 /* XXX Future: return the state rather than these funky bits */ 552 rdsv3_conn_info_set(cinfo->flags, 553 atomic_get(&conn->c_state) == RDSV3_CONN_CONNECTING, 554 CONNECTING); 555 rdsv3_conn_info_set(cinfo->flags, 556 atomic_get(&conn->c_state) == RDSV3_CONN_UP, 557 CONNECTED); 558 return (1); 559 } 560 561 static void 562 rdsv3_conn_info(struct rsock *sock, unsigned int len, 563 struct rdsv3_info_iterator *iter, struct rdsv3_info_lengths *lens) 564 { 565 rdsv3_for_each_conn_info(sock, len, iter, lens, 566 rdsv3_conn_info_visitor, sizeof (struct rds_info_connection)); 567 } 568 569 int 570 rdsv3_conn_init() 571 { 572 RDSV3_DPRINTF4("rdsv3_conn_init", "Enter"); 573 574 rdsv3_conn_slab = kmem_cache_create("rdsv3_connection", 575 sizeof (struct rdsv3_connection), 0, rdsv3_conn_constructor, 576 rdsv3_conn_destructor, NULL, NULL, NULL, 0); 577 if (!rdsv3_conn_slab) { 578 RDSV3_DPRINTF2("rdsv3_conn_init", 579 "kmem_cache_create(rdsv3_conn_slab) failed"); 580 return (-ENOMEM); 581 } 582 583 avl_create(&rdsv3_conn_hash, rdsv3_conn_compare, 584 sizeof (struct rdsv3_connection), offsetof(struct rdsv3_connection, 585 c_hash_node)); 586 587 rw_init(&rdsv3_conn_lock, NULL, RW_DRIVER, NULL); 588 589 rdsv3_loop_init(); 590 591 rdsv3_info_register_func(RDS_INFO_CONNECTIONS, rdsv3_conn_info); 592 rdsv3_info_register_func(RDS_INFO_SEND_MESSAGES, 593 rdsv3_conn_message_info_send); 594 rdsv3_info_register_func(RDS_INFO_RETRANS_MESSAGES, 595 rdsv3_conn_message_info_retrans); 596 597 RDSV3_DPRINTF4("rdsv3_conn_init", "Return"); 598 599 return (0); 600 } 601 602 void 603 rdsv3_conn_exit() 604 { 605 RDSV3_DPRINTF4("rdsv3_conn_exit", "Enter"); 606 607 rdsv3_loop_exit(); 608 609 rw_destroy(&rdsv3_conn_lock); 610 avl_destroy(&rdsv3_conn_hash); 611 612 ASSERT(rdsv3_conn_slab); 613 kmem_cache_destroy(rdsv3_conn_slab); 614 615 RDSV3_DPRINTF4("rdsv3_conn_exit", "Return"); 616 } 617 618 /* 619 * Force a disconnect 620 */ 621 void 622 rdsv3_conn_drop(struct rdsv3_connection *conn) 623 { 624 conn->c_state = RDSV3_CONN_ERROR; 625 rdsv3_queue_work(rdsv3_wq, &conn->c_down_w); 626 } 627