1/* 2 * Copyright (c) 2004, 2005 Intel Corporation. All rights reserved. 3 * Copyright (c) 2004 Topspin Corporation. All rights reserved. 4 * Copyright (c) 2004, 2005 Voltaire Corporation. All rights reserved. 5 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved. 6 * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved. 7 * Copyright (c) 2005 Network Appliance, Inc. All rights reserved. 8 * 9 * This software is available to you under a choice of one of two 10 * licenses. You may choose to be licensed under the terms of the GNU 11 * General Public License (GPL) Version 2, available from the file 12 * COPYING in the main directory of this source tree, or the 13 * OpenIB.org BSD license below: 14 * 15 * Redistribution and use in source and binary forms, with or 16 * without modification, are permitted provided that the following 17 * conditions are met: 18 * 19 * - Redistributions of source code must retain the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer. 22 * 23 * - Redistributions in binary form must reproduce the above 24 * copyright notice, this list of conditions and the following 25 * disclaimer in the documentation and/or other materials 26 * provided with the distribution. 27 * 28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 29 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 31 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 32 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 33 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 34 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 35 * SOFTWARE. 36 * 37 */ 38#include <linux/dma-mapping.h> 39#include <linux/err.h> 40#include <linux/idr.h> 41#include <linux/interrupt.h> 42#include <linux/rbtree.h> 43#include <linux/sched.h> 44#include <linux/spinlock.h> 45#include <linux/workqueue.h> 46#include <linux/completion.h> 47#include <linux/slab.h> 48#include <linux/module.h> 49#include <linux/sysctl.h> 50 51#include <rdma/iw_cm.h> 52#include <rdma/ib_addr.h> 53#include <rdma/iw_portmap.h> 54#include <rdma/rdma_netlink.h> 55 56#include "iwcm.h" 57 58MODULE_AUTHOR("Tom Tucker"); 59MODULE_DESCRIPTION("iWARP CM"); 60MODULE_LICENSE("Dual BSD/GPL"); 61 62static const char * const iwcm_rej_reason_strs[] = { 63 [ECONNRESET] = "reset by remote host", 64 [ECONNREFUSED] = "refused by remote application", 65 [ETIMEDOUT] = "setup timeout", 66}; 67 68const char *__attribute_const__ iwcm_reject_msg(int reason) 69{ 70 size_t index; 71 72 /* iWARP uses negative errnos */ 73 index = -reason; 74 75 if (index < ARRAY_SIZE(iwcm_rej_reason_strs) && 76 iwcm_rej_reason_strs[index]) 77 return iwcm_rej_reason_strs[index]; 78 else 79 return "unrecognized reason"; 80} 81EXPORT_SYMBOL(iwcm_reject_msg); 82 83static struct rdma_nl_cbs iwcm_nl_cb_table[RDMA_NL_IWPM_NUM_OPS] = { 84 [RDMA_NL_IWPM_REG_PID] = {.dump = iwpm_register_pid_cb}, 85 [RDMA_NL_IWPM_ADD_MAPPING] = {.dump = iwpm_add_mapping_cb}, 86 [RDMA_NL_IWPM_QUERY_MAPPING] = {.dump = iwpm_add_and_query_mapping_cb}, 87 [RDMA_NL_IWPM_REMOTE_INFO] = {.dump = iwpm_remote_info_cb}, 88 [RDMA_NL_IWPM_HANDLE_ERR] = {.dump = iwpm_mapping_error_cb}, 89 [RDMA_NL_IWPM_MAPINFO] = {.dump = iwpm_mapping_info_cb}, 90 [RDMA_NL_IWPM_MAPINFO_NUM] = {.dump = iwpm_ack_mapping_info_cb}, 91 [RDMA_NL_IWPM_HELLO] = {.dump = iwpm_hello_cb} 92}; 93 94static struct workqueue_struct *iwcm_wq; 95struct iwcm_work { 96 struct work_struct work; 97 struct iwcm_id_private *cm_id; 98 struct list_head list; 99 struct iw_cm_event event; 100 struct list_head free_list; 101}; 102 103static unsigned int default_backlog = 256; 104 105static struct ctl_table_header *iwcm_ctl_table_hdr; 106static struct ctl_table iwcm_ctl_table[] = { 107 { 108 .procname = "default_backlog", 109 .data = &default_backlog, 110 .maxlen = sizeof(default_backlog), 111 .mode = 0644, 112 .proc_handler = proc_dointvec, 113 }, 114}; 115 116/* 117 * The following services provide a mechanism for pre-allocating iwcm_work 118 * elements. The design pre-allocates them based on the cm_id type: 119 * LISTENING IDS: Get enough elements preallocated to handle the 120 * listen backlog. 121 * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE 122 * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE 123 * 124 * Allocating them in connect and listen avoids having to deal 125 * with allocation failures on the event upcall from the provider (which 126 * is called in the interrupt context). 127 * 128 * One exception is when creating the cm_id for incoming connection requests. 129 * There are two cases: 130 * 1) in the event upcall, cm_event_handler(), for a listening cm_id. If 131 * the backlog is exceeded, then no more connection request events will 132 * be processed. cm_event_handler() returns -ENOMEM in this case. Its up 133 * to the provider to reject the connection request. 134 * 2) in the connection request workqueue handler, cm_conn_req_handler(). 135 * If work elements cannot be allocated for the new connect request cm_id, 136 * then IWCM will call the provider reject method. This is ok since 137 * cm_conn_req_handler() runs in the workqueue thread context. 138 */ 139 140static struct iwcm_work *get_work(struct iwcm_id_private *cm_id_priv) 141{ 142 struct iwcm_work *work; 143 144 if (list_empty(&cm_id_priv->work_free_list)) 145 return NULL; 146 work = list_entry(cm_id_priv->work_free_list.next, struct iwcm_work, 147 free_list); 148 list_del_init(&work->free_list); 149 return work; 150} 151 152static void put_work(struct iwcm_work *work) 153{ 154 list_add(&work->free_list, &work->cm_id->work_free_list); 155} 156 157static void dealloc_work_entries(struct iwcm_id_private *cm_id_priv) 158{ 159 struct list_head *e, *tmp; 160 161 list_for_each_safe(e, tmp, &cm_id_priv->work_free_list) { 162 list_del(e); 163 kfree(list_entry(e, struct iwcm_work, free_list)); 164 } 165} 166 167static int alloc_work_entries(struct iwcm_id_private *cm_id_priv, int count) 168{ 169 struct iwcm_work *work; 170 171 BUG_ON(!list_empty(&cm_id_priv->work_free_list)); 172 while (count--) { 173 work = kmalloc(sizeof(struct iwcm_work), GFP_KERNEL); 174 if (!work) { 175 dealloc_work_entries(cm_id_priv); 176 return -ENOMEM; 177 } 178 work->cm_id = cm_id_priv; 179 INIT_LIST_HEAD(&work->list); 180 put_work(work); 181 } 182 return 0; 183} 184 185/* 186 * Save private data from incoming connection requests to 187 * iw_cm_event, so the low level driver doesn't have to. Adjust 188 * the event ptr to point to the local copy. 189 */ 190static int copy_private_data(struct iw_cm_event *event) 191{ 192 void *p; 193 194 p = kmemdup(event->private_data, event->private_data_len, GFP_ATOMIC); 195 if (!p) 196 return -ENOMEM; 197 event->private_data = p; 198 return 0; 199} 200 201static void free_cm_id(struct iwcm_id_private *cm_id_priv) 202{ 203 dealloc_work_entries(cm_id_priv); 204 kfree(cm_id_priv); 205} 206 207/* 208 * Release a reference on cm_id. If the last reference is being 209 * released, free the cm_id and return 1. 210 */ 211static int iwcm_deref_id(struct iwcm_id_private *cm_id_priv) 212{ 213 if (refcount_dec_and_test(&cm_id_priv->refcount)) { 214 BUG_ON(!list_empty(&cm_id_priv->work_list)); 215 free_cm_id(cm_id_priv); 216 return 1; 217 } 218 219 return 0; 220} 221 222static void add_ref(struct iw_cm_id *cm_id) 223{ 224 struct iwcm_id_private *cm_id_priv; 225 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 226 refcount_inc(&cm_id_priv->refcount); 227} 228 229static void rem_ref(struct iw_cm_id *cm_id) 230{ 231 struct iwcm_id_private *cm_id_priv; 232 233 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 234 235 (void)iwcm_deref_id(cm_id_priv); 236} 237 238static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *event); 239 240struct iw_cm_id *iw_create_cm_id(struct ib_device *device, 241 iw_cm_handler cm_handler, 242 void *context) 243{ 244 struct iwcm_id_private *cm_id_priv; 245 246 cm_id_priv = kzalloc(sizeof(*cm_id_priv), GFP_KERNEL); 247 if (!cm_id_priv) 248 return ERR_PTR(-ENOMEM); 249 250 cm_id_priv->state = IW_CM_STATE_IDLE; 251 cm_id_priv->id.device = device; 252 cm_id_priv->id.cm_handler = cm_handler; 253 cm_id_priv->id.context = context; 254 cm_id_priv->id.event_handler = cm_event_handler; 255 cm_id_priv->id.add_ref = add_ref; 256 cm_id_priv->id.rem_ref = rem_ref; 257 spin_lock_init(&cm_id_priv->lock); 258 refcount_set(&cm_id_priv->refcount, 1); 259 init_waitqueue_head(&cm_id_priv->connect_wait); 260 init_completion(&cm_id_priv->destroy_comp); 261 INIT_LIST_HEAD(&cm_id_priv->work_list); 262 INIT_LIST_HEAD(&cm_id_priv->work_free_list); 263 264 return &cm_id_priv->id; 265} 266EXPORT_SYMBOL(iw_create_cm_id); 267 268 269static int iwcm_modify_qp_err(struct ib_qp *qp) 270{ 271 struct ib_qp_attr qp_attr; 272 273 if (!qp) 274 return -EINVAL; 275 276 qp_attr.qp_state = IB_QPS_ERR; 277 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE); 278} 279 280/* 281 * This is really the RDMAC CLOSING state. It is most similar to the 282 * IB SQD QP state. 283 */ 284static int iwcm_modify_qp_sqd(struct ib_qp *qp) 285{ 286 struct ib_qp_attr qp_attr; 287 288 BUG_ON(qp == NULL); 289 qp_attr.qp_state = IB_QPS_SQD; 290 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE); 291} 292 293/* 294 * CM_ID <-- CLOSING 295 * 296 * Block if a passive or active connection is currently being processed. Then 297 * process the event as follows: 298 * - If we are ESTABLISHED, move to CLOSING and modify the QP state 299 * based on the abrupt flag 300 * - If the connection is already in the CLOSING or IDLE state, the peer is 301 * disconnecting concurrently with us and we've already seen the 302 * DISCONNECT event -- ignore the request and return 0 303 * - Disconnect on a listening endpoint returns -EINVAL 304 */ 305int iw_cm_disconnect(struct iw_cm_id *cm_id, int abrupt) 306{ 307 struct iwcm_id_private *cm_id_priv; 308 unsigned long flags; 309 int ret = 0; 310 struct ib_qp *qp = NULL; 311 312 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 313 /* Wait if we're currently in a connect or accept downcall */ 314 wait_event(cm_id_priv->connect_wait, 315 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags)); 316 317 spin_lock_irqsave(&cm_id_priv->lock, flags); 318 switch (cm_id_priv->state) { 319 case IW_CM_STATE_ESTABLISHED: 320 cm_id_priv->state = IW_CM_STATE_CLOSING; 321 322 /* QP could be <nul> for user-mode client */ 323 if (cm_id_priv->qp) 324 qp = cm_id_priv->qp; 325 else 326 ret = -EINVAL; 327 break; 328 case IW_CM_STATE_LISTEN: 329 ret = -EINVAL; 330 break; 331 case IW_CM_STATE_CLOSING: 332 /* remote peer closed first */ 333 case IW_CM_STATE_IDLE: 334 /* accept or connect returned !0 */ 335 break; 336 case IW_CM_STATE_CONN_RECV: 337 /* 338 * App called disconnect before/without calling accept after 339 * connect_request event delivered. 340 */ 341 break; 342 case IW_CM_STATE_CONN_SENT: 343 /* Can only get here if wait above fails */ 344 default: 345 BUG(); 346 } 347 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 348 349 if (qp) { 350 if (abrupt) 351 ret = iwcm_modify_qp_err(qp); 352 else 353 ret = iwcm_modify_qp_sqd(qp); 354 355 /* 356 * If both sides are disconnecting the QP could 357 * already be in ERR or SQD states 358 */ 359 ret = 0; 360 } 361 362 return ret; 363} 364EXPORT_SYMBOL(iw_cm_disconnect); 365 366/* 367 * CM_ID <-- DESTROYING 368 * 369 * Clean up all resources associated with the connection and release 370 * the initial reference taken by iw_create_cm_id. 371 */ 372static void destroy_cm_id(struct iw_cm_id *cm_id) 373{ 374 struct iwcm_id_private *cm_id_priv; 375 struct ib_qp *qp; 376 unsigned long flags; 377 378 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 379 /* 380 * Wait if we're currently in a connect or accept downcall. A 381 * listening endpoint should never block here. 382 */ 383 wait_event(cm_id_priv->connect_wait, 384 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags)); 385 386 /* 387 * Since we're deleting the cm_id, drop any events that 388 * might arrive before the last dereference. 389 */ 390 set_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags); 391 392 spin_lock_irqsave(&cm_id_priv->lock, flags); 393 qp = cm_id_priv->qp; 394 cm_id_priv->qp = NULL; 395 396 switch (cm_id_priv->state) { 397 case IW_CM_STATE_LISTEN: 398 cm_id_priv->state = IW_CM_STATE_DESTROYING; 399 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 400 /* destroy the listening endpoint */ 401 cm_id->device->ops.iw_destroy_listen(cm_id); 402 spin_lock_irqsave(&cm_id_priv->lock, flags); 403 break; 404 case IW_CM_STATE_ESTABLISHED: 405 cm_id_priv->state = IW_CM_STATE_DESTROYING; 406 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 407 /* Abrupt close of the connection */ 408 (void)iwcm_modify_qp_err(qp); 409 spin_lock_irqsave(&cm_id_priv->lock, flags); 410 break; 411 case IW_CM_STATE_IDLE: 412 case IW_CM_STATE_CLOSING: 413 cm_id_priv->state = IW_CM_STATE_DESTROYING; 414 break; 415 case IW_CM_STATE_CONN_RECV: 416 /* 417 * App called destroy before/without calling accept after 418 * receiving connection request event notification or 419 * returned non zero from the event callback function. 420 * In either case, must tell the provider to reject. 421 */ 422 cm_id_priv->state = IW_CM_STATE_DESTROYING; 423 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 424 cm_id->device->ops.iw_reject(cm_id, NULL, 0); 425 spin_lock_irqsave(&cm_id_priv->lock, flags); 426 break; 427 case IW_CM_STATE_CONN_SENT: 428 case IW_CM_STATE_DESTROYING: 429 default: 430 BUG(); 431 break; 432 } 433 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 434 if (qp) 435 cm_id_priv->id.device->ops.iw_rem_ref(qp); 436 437 if (cm_id->mapped) { 438 iwpm_remove_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr); 439 iwpm_remove_mapping(&cm_id->local_addr, RDMA_NL_IWCM); 440 } 441 442 (void)iwcm_deref_id(cm_id_priv); 443} 444 445/* 446 * This function is only called by the application thread and cannot 447 * be called by the event thread. The function will wait for all 448 * references to be released on the cm_id and then kfree the cm_id 449 * object. 450 */ 451void iw_destroy_cm_id(struct iw_cm_id *cm_id) 452{ 453 destroy_cm_id(cm_id); 454} 455EXPORT_SYMBOL(iw_destroy_cm_id); 456 457/** 458 * iw_cm_check_wildcard - If IP address is 0 then use original 459 * @pm_addr: sockaddr containing the ip to check for wildcard 460 * @cm_addr: sockaddr containing the actual IP address 461 * @cm_outaddr: sockaddr to set IP addr which leaving port 462 * 463 * Checks the pm_addr for wildcard and then sets cm_outaddr's 464 * IP to the actual (cm_addr). 465 */ 466static void iw_cm_check_wildcard(struct sockaddr_storage *pm_addr, 467 struct sockaddr_storage *cm_addr, 468 struct sockaddr_storage *cm_outaddr) 469{ 470 if (pm_addr->ss_family == AF_INET) { 471 struct sockaddr_in *pm4_addr = (struct sockaddr_in *)pm_addr; 472 473 if (pm4_addr->sin_addr.s_addr == htonl(INADDR_ANY)) { 474 struct sockaddr_in *cm4_addr = 475 (struct sockaddr_in *)cm_addr; 476 struct sockaddr_in *cm4_outaddr = 477 (struct sockaddr_in *)cm_outaddr; 478 479 cm4_outaddr->sin_addr = cm4_addr->sin_addr; 480 } 481 } else { 482 struct sockaddr_in6 *pm6_addr = (struct sockaddr_in6 *)pm_addr; 483 484 if (ipv6_addr_type(&pm6_addr->sin6_addr) == IPV6_ADDR_ANY) { 485 struct sockaddr_in6 *cm6_addr = 486 (struct sockaddr_in6 *)cm_addr; 487 struct sockaddr_in6 *cm6_outaddr = 488 (struct sockaddr_in6 *)cm_outaddr; 489 490 cm6_outaddr->sin6_addr = cm6_addr->sin6_addr; 491 } 492 } 493} 494 495/** 496 * iw_cm_map - Use portmapper to map the ports 497 * @cm_id: connection manager pointer 498 * @active: Indicates the active side when true 499 * returns nonzero for error only if iwpm_create_mapinfo() fails 500 * 501 * Tries to add a mapping for a port using the Portmapper. If 502 * successful in mapping the IP/Port it will check the remote 503 * mapped IP address for a wildcard IP address and replace the 504 * zero IP address with the remote_addr. 505 */ 506static int iw_cm_map(struct iw_cm_id *cm_id, bool active) 507{ 508 const char *devname = dev_name(&cm_id->device->dev); 509 const char *ifname = cm_id->device->iw_ifname; 510 struct iwpm_dev_data pm_reg_msg = {}; 511 struct iwpm_sa_data pm_msg; 512 int status; 513 514 if (strlen(devname) >= sizeof(pm_reg_msg.dev_name) || 515 strlen(ifname) >= sizeof(pm_reg_msg.if_name)) 516 return -EINVAL; 517 518 cm_id->m_local_addr = cm_id->local_addr; 519 cm_id->m_remote_addr = cm_id->remote_addr; 520 521 strcpy(pm_reg_msg.dev_name, devname); 522 strcpy(pm_reg_msg.if_name, ifname); 523 524 if (iwpm_register_pid(&pm_reg_msg, RDMA_NL_IWCM) || 525 !iwpm_valid_pid()) 526 return 0; 527 528 cm_id->mapped = true; 529 pm_msg.loc_addr = cm_id->local_addr; 530 pm_msg.rem_addr = cm_id->remote_addr; 531 pm_msg.flags = (cm_id->device->iw_driver_flags & IW_F_NO_PORT_MAP) ? 532 IWPM_FLAGS_NO_PORT_MAP : 0; 533 if (active) 534 status = iwpm_add_and_query_mapping(&pm_msg, 535 RDMA_NL_IWCM); 536 else 537 status = iwpm_add_mapping(&pm_msg, RDMA_NL_IWCM); 538 539 if (!status) { 540 cm_id->m_local_addr = pm_msg.mapped_loc_addr; 541 if (active) { 542 cm_id->m_remote_addr = pm_msg.mapped_rem_addr; 543 iw_cm_check_wildcard(&pm_msg.mapped_rem_addr, 544 &cm_id->remote_addr, 545 &cm_id->m_remote_addr); 546 } 547 } 548 549 return iwpm_create_mapinfo(&cm_id->local_addr, 550 &cm_id->m_local_addr, 551 RDMA_NL_IWCM, pm_msg.flags); 552} 553 554/* 555 * CM_ID <-- LISTEN 556 * 557 * Start listening for connect requests. Generates one CONNECT_REQUEST 558 * event for each inbound connect request. 559 */ 560int iw_cm_listen(struct iw_cm_id *cm_id, int backlog) 561{ 562 struct iwcm_id_private *cm_id_priv; 563 unsigned long flags; 564 int ret; 565 566 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 567 568 if (!backlog) 569 backlog = default_backlog; 570 571 ret = alloc_work_entries(cm_id_priv, backlog); 572 if (ret) 573 return ret; 574 575 spin_lock_irqsave(&cm_id_priv->lock, flags); 576 switch (cm_id_priv->state) { 577 case IW_CM_STATE_IDLE: 578 cm_id_priv->state = IW_CM_STATE_LISTEN; 579 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 580 ret = iw_cm_map(cm_id, false); 581 if (!ret) 582 ret = cm_id->device->ops.iw_create_listen(cm_id, 583 backlog); 584 if (ret) 585 cm_id_priv->state = IW_CM_STATE_IDLE; 586 spin_lock_irqsave(&cm_id_priv->lock, flags); 587 break; 588 default: 589 ret = -EINVAL; 590 } 591 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 592 593 return ret; 594} 595EXPORT_SYMBOL(iw_cm_listen); 596 597/* 598 * CM_ID <-- IDLE 599 * 600 * Rejects an inbound connection request. No events are generated. 601 */ 602int iw_cm_reject(struct iw_cm_id *cm_id, 603 const void *private_data, 604 u8 private_data_len) 605{ 606 struct iwcm_id_private *cm_id_priv; 607 unsigned long flags; 608 int ret; 609 610 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 611 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 612 613 spin_lock_irqsave(&cm_id_priv->lock, flags); 614 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) { 615 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 616 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 617 wake_up_all(&cm_id_priv->connect_wait); 618 return -EINVAL; 619 } 620 cm_id_priv->state = IW_CM_STATE_IDLE; 621 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 622 623 ret = cm_id->device->ops.iw_reject(cm_id, private_data, 624 private_data_len); 625 626 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 627 wake_up_all(&cm_id_priv->connect_wait); 628 629 return ret; 630} 631EXPORT_SYMBOL(iw_cm_reject); 632 633/* 634 * CM_ID <-- ESTABLISHED 635 * 636 * Accepts an inbound connection request and generates an ESTABLISHED 637 * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block 638 * until the ESTABLISHED event is received from the provider. 639 */ 640int iw_cm_accept(struct iw_cm_id *cm_id, 641 struct iw_cm_conn_param *iw_param) 642{ 643 struct iwcm_id_private *cm_id_priv; 644 struct ib_qp *qp; 645 unsigned long flags; 646 int ret; 647 648 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 649 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 650 651 spin_lock_irqsave(&cm_id_priv->lock, flags); 652 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) { 653 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 654 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 655 wake_up_all(&cm_id_priv->connect_wait); 656 return -EINVAL; 657 } 658 /* Get the ib_qp given the QPN */ 659 qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn); 660 if (!qp) { 661 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 662 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 663 wake_up_all(&cm_id_priv->connect_wait); 664 return -EINVAL; 665 } 666 cm_id->device->ops.iw_add_ref(qp); 667 cm_id_priv->qp = qp; 668 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 669 670 ret = cm_id->device->ops.iw_accept(cm_id, iw_param); 671 if (ret) { 672 /* An error on accept precludes provider events */ 673 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV); 674 cm_id_priv->state = IW_CM_STATE_IDLE; 675 spin_lock_irqsave(&cm_id_priv->lock, flags); 676 qp = cm_id_priv->qp; 677 cm_id_priv->qp = NULL; 678 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 679 if (qp) 680 cm_id->device->ops.iw_rem_ref(qp); 681 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 682 wake_up_all(&cm_id_priv->connect_wait); 683 } 684 685 return ret; 686} 687EXPORT_SYMBOL(iw_cm_accept); 688 689/* 690 * Active Side: CM_ID <-- CONN_SENT 691 * 692 * If successful, results in the generation of a CONNECT_REPLY 693 * event. iw_cm_disconnect and iw_cm_destroy will block until the 694 * CONNECT_REPLY event is received from the provider. 695 */ 696int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param) 697{ 698 struct iwcm_id_private *cm_id_priv; 699 int ret; 700 unsigned long flags; 701 struct ib_qp *qp = NULL; 702 703 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 704 705 ret = alloc_work_entries(cm_id_priv, 4); 706 if (ret) 707 return ret; 708 709 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 710 spin_lock_irqsave(&cm_id_priv->lock, flags); 711 712 if (cm_id_priv->state != IW_CM_STATE_IDLE) { 713 ret = -EINVAL; 714 goto err; 715 } 716 717 /* Get the ib_qp given the QPN */ 718 qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn); 719 if (!qp) { 720 ret = -EINVAL; 721 goto err; 722 } 723 cm_id->device->ops.iw_add_ref(qp); 724 cm_id_priv->qp = qp; 725 cm_id_priv->state = IW_CM_STATE_CONN_SENT; 726 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 727 728 ret = iw_cm_map(cm_id, true); 729 if (!ret) 730 ret = cm_id->device->ops.iw_connect(cm_id, iw_param); 731 if (!ret) 732 return 0; /* success */ 733 734 spin_lock_irqsave(&cm_id_priv->lock, flags); 735 qp = cm_id_priv->qp; 736 cm_id_priv->qp = NULL; 737 cm_id_priv->state = IW_CM_STATE_IDLE; 738err: 739 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 740 if (qp) 741 cm_id->device->ops.iw_rem_ref(qp); 742 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 743 wake_up_all(&cm_id_priv->connect_wait); 744 return ret; 745} 746EXPORT_SYMBOL(iw_cm_connect); 747 748/* 749 * Passive Side: new CM_ID <-- CONN_RECV 750 * 751 * Handles an inbound connect request. The function creates a new 752 * iw_cm_id to represent the new connection and inherits the client 753 * callback function and other attributes from the listening parent. 754 * 755 * The work item contains a pointer to the listen_cm_id and the event. The 756 * listen_cm_id contains the client cm_handler, context and 757 * device. These are copied when the device is cloned. The event 758 * contains the new four tuple. 759 * 760 * An error on the child should not affect the parent, so this 761 * function does not return a value. 762 */ 763static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv, 764 struct iw_cm_event *iw_event) 765{ 766 unsigned long flags; 767 struct iw_cm_id *cm_id; 768 struct iwcm_id_private *cm_id_priv; 769 int ret; 770 771 /* 772 * The provider should never generate a connection request 773 * event with a bad status. 774 */ 775 BUG_ON(iw_event->status); 776 777 cm_id = iw_create_cm_id(listen_id_priv->id.device, 778 listen_id_priv->id.cm_handler, 779 listen_id_priv->id.context); 780 /* If the cm_id could not be created, ignore the request */ 781 if (IS_ERR(cm_id)) 782 goto out; 783 784 cm_id->provider_data = iw_event->provider_data; 785 cm_id->m_local_addr = iw_event->local_addr; 786 cm_id->m_remote_addr = iw_event->remote_addr; 787 cm_id->local_addr = listen_id_priv->id.local_addr; 788 789 ret = iwpm_get_remote_info(&listen_id_priv->id.m_local_addr, 790 &iw_event->remote_addr, 791 &cm_id->remote_addr, 792 RDMA_NL_IWCM); 793 if (ret) { 794 cm_id->remote_addr = iw_event->remote_addr; 795 } else { 796 iw_cm_check_wildcard(&listen_id_priv->id.m_local_addr, 797 &iw_event->local_addr, 798 &cm_id->local_addr); 799 iw_event->local_addr = cm_id->local_addr; 800 iw_event->remote_addr = cm_id->remote_addr; 801 } 802 803 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 804 cm_id_priv->state = IW_CM_STATE_CONN_RECV; 805 806 /* 807 * We could be destroying the listening id. If so, ignore this 808 * upcall. 809 */ 810 spin_lock_irqsave(&listen_id_priv->lock, flags); 811 if (listen_id_priv->state != IW_CM_STATE_LISTEN) { 812 spin_unlock_irqrestore(&listen_id_priv->lock, flags); 813 iw_cm_reject(cm_id, NULL, 0); 814 iw_destroy_cm_id(cm_id); 815 goto out; 816 } 817 spin_unlock_irqrestore(&listen_id_priv->lock, flags); 818 819 ret = alloc_work_entries(cm_id_priv, 3); 820 if (ret) { 821 iw_cm_reject(cm_id, NULL, 0); 822 iw_destroy_cm_id(cm_id); 823 goto out; 824 } 825 826 /* Call the client CM handler */ 827 ret = cm_id->cm_handler(cm_id, iw_event); 828 if (ret) { 829 iw_cm_reject(cm_id, NULL, 0); 830 iw_destroy_cm_id(cm_id); 831 } 832 833out: 834 if (iw_event->private_data_len) 835 kfree(iw_event->private_data); 836} 837 838/* 839 * Passive Side: CM_ID <-- ESTABLISHED 840 * 841 * The provider generated an ESTABLISHED event which means that 842 * the MPA negotion has completed successfully and we are now in MPA 843 * FPDU mode. 844 * 845 * This event can only be received in the CONN_RECV state. If the 846 * remote peer closed, the ESTABLISHED event would be received followed 847 * by the CLOSE event. If the app closes, it will block until we wake 848 * it up after processing this event. 849 */ 850static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv, 851 struct iw_cm_event *iw_event) 852{ 853 unsigned long flags; 854 int ret; 855 856 spin_lock_irqsave(&cm_id_priv->lock, flags); 857 858 /* 859 * We clear the CONNECT_WAIT bit here to allow the callback 860 * function to call iw_cm_disconnect. Calling iw_destroy_cm_id 861 * from a callback handler is not allowed. 862 */ 863 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 864 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV); 865 cm_id_priv->state = IW_CM_STATE_ESTABLISHED; 866 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 867 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event); 868 wake_up_all(&cm_id_priv->connect_wait); 869 870 return ret; 871} 872 873/* 874 * Active Side: CM_ID <-- ESTABLISHED 875 * 876 * The app has called connect and is waiting for the established event to 877 * post it's requests to the server. This event will wake up anyone 878 * blocked in iw_cm_disconnect or iw_destroy_id. 879 */ 880static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv, 881 struct iw_cm_event *iw_event) 882{ 883 struct ib_qp *qp = NULL; 884 unsigned long flags; 885 int ret; 886 887 spin_lock_irqsave(&cm_id_priv->lock, flags); 888 /* 889 * Clear the connect wait bit so a callback function calling 890 * iw_cm_disconnect will not wait and deadlock this thread 891 */ 892 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags); 893 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT); 894 if (iw_event->status == 0) { 895 cm_id_priv->id.m_local_addr = iw_event->local_addr; 896 cm_id_priv->id.m_remote_addr = iw_event->remote_addr; 897 iw_event->local_addr = cm_id_priv->id.local_addr; 898 iw_event->remote_addr = cm_id_priv->id.remote_addr; 899 cm_id_priv->state = IW_CM_STATE_ESTABLISHED; 900 } else { 901 /* REJECTED or RESET */ 902 qp = cm_id_priv->qp; 903 cm_id_priv->qp = NULL; 904 cm_id_priv->state = IW_CM_STATE_IDLE; 905 } 906 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 907 if (qp) 908 cm_id_priv->id.device->ops.iw_rem_ref(qp); 909 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event); 910 911 if (iw_event->private_data_len) 912 kfree(iw_event->private_data); 913 914 /* Wake up waiters on connect complete */ 915 wake_up_all(&cm_id_priv->connect_wait); 916 917 return ret; 918} 919 920/* 921 * CM_ID <-- CLOSING 922 * 923 * If in the ESTABLISHED state, move to CLOSING. 924 */ 925static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv, 926 struct iw_cm_event *iw_event) 927{ 928 unsigned long flags; 929 930 spin_lock_irqsave(&cm_id_priv->lock, flags); 931 if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED) 932 cm_id_priv->state = IW_CM_STATE_CLOSING; 933 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 934} 935 936/* 937 * CM_ID <-- IDLE 938 * 939 * If in the ESTBLISHED or CLOSING states, the QP will have have been 940 * moved by the provider to the ERR state. Disassociate the CM_ID from 941 * the QP, move to IDLE, and remove the 'connected' reference. 942 * 943 * If in some other state, the cm_id was destroyed asynchronously. 944 * This is the last reference that will result in waking up 945 * the app thread blocked in iw_destroy_cm_id. 946 */ 947static int cm_close_handler(struct iwcm_id_private *cm_id_priv, 948 struct iw_cm_event *iw_event) 949{ 950 struct ib_qp *qp; 951 unsigned long flags; 952 int ret = 0, notify_event = 0; 953 spin_lock_irqsave(&cm_id_priv->lock, flags); 954 qp = cm_id_priv->qp; 955 cm_id_priv->qp = NULL; 956 957 switch (cm_id_priv->state) { 958 case IW_CM_STATE_ESTABLISHED: 959 case IW_CM_STATE_CLOSING: 960 cm_id_priv->state = IW_CM_STATE_IDLE; 961 notify_event = 1; 962 break; 963 case IW_CM_STATE_DESTROYING: 964 break; 965 default: 966 BUG(); 967 } 968 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 969 970 if (qp) 971 cm_id_priv->id.device->ops.iw_rem_ref(qp); 972 if (notify_event) 973 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event); 974 return ret; 975} 976 977static int process_event(struct iwcm_id_private *cm_id_priv, 978 struct iw_cm_event *iw_event) 979{ 980 int ret = 0; 981 982 switch (iw_event->event) { 983 case IW_CM_EVENT_CONNECT_REQUEST: 984 cm_conn_req_handler(cm_id_priv, iw_event); 985 break; 986 case IW_CM_EVENT_CONNECT_REPLY: 987 ret = cm_conn_rep_handler(cm_id_priv, iw_event); 988 break; 989 case IW_CM_EVENT_ESTABLISHED: 990 ret = cm_conn_est_handler(cm_id_priv, iw_event); 991 break; 992 case IW_CM_EVENT_DISCONNECT: 993 cm_disconnect_handler(cm_id_priv, iw_event); 994 break; 995 case IW_CM_EVENT_CLOSE: 996 ret = cm_close_handler(cm_id_priv, iw_event); 997 break; 998 default: 999 BUG(); 1000 } 1001 1002 return ret; 1003} 1004 1005/* 1006 * Process events on the work_list for the cm_id. If the callback 1007 * function requests that the cm_id be deleted, a flag is set in the 1008 * cm_id flags to indicate that when the last reference is 1009 * removed, the cm_id is to be destroyed. This is necessary to 1010 * distinguish between an object that will be destroyed by the app 1011 * thread asleep on the destroy_comp list vs. an object destroyed 1012 * here synchronously when the last reference is removed. 1013 */ 1014static void cm_work_handler(struct work_struct *_work) 1015{ 1016 struct iwcm_work *work = container_of(_work, struct iwcm_work, work); 1017 struct iw_cm_event levent; 1018 struct iwcm_id_private *cm_id_priv = work->cm_id; 1019 unsigned long flags; 1020 int empty; 1021 int ret = 0; 1022 1023 spin_lock_irqsave(&cm_id_priv->lock, flags); 1024 empty = list_empty(&cm_id_priv->work_list); 1025 while (!empty) { 1026 work = list_entry(cm_id_priv->work_list.next, 1027 struct iwcm_work, list); 1028 list_del_init(&work->list); 1029 empty = list_empty(&cm_id_priv->work_list); 1030 levent = work->event; 1031 put_work(work); 1032 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 1033 1034 if (!test_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags)) { 1035 ret = process_event(cm_id_priv, &levent); 1036 if (ret) 1037 destroy_cm_id(&cm_id_priv->id); 1038 } else 1039 pr_debug("dropping event %d\n", levent.event); 1040 if (iwcm_deref_id(cm_id_priv)) 1041 return; 1042 if (empty) 1043 return; 1044 spin_lock_irqsave(&cm_id_priv->lock, flags); 1045 } 1046 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 1047} 1048 1049/* 1050 * This function is called on interrupt context. Schedule events on 1051 * the iwcm_wq thread to allow callback functions to downcall into 1052 * the CM and/or block. Events are queued to a per-CM_ID 1053 * work_list. If this is the first event on the work_list, the work 1054 * element is also queued on the iwcm_wq thread. 1055 * 1056 * Each event holds a reference on the cm_id. Until the last posted 1057 * event has been delivered and processed, the cm_id cannot be 1058 * deleted. 1059 * 1060 * Returns: 1061 * 0 - the event was handled. 1062 * -ENOMEM - the event was not handled due to lack of resources. 1063 */ 1064static int cm_event_handler(struct iw_cm_id *cm_id, 1065 struct iw_cm_event *iw_event) 1066{ 1067 struct iwcm_work *work; 1068 struct iwcm_id_private *cm_id_priv; 1069 unsigned long flags; 1070 int ret = 0; 1071 1072 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 1073 1074 spin_lock_irqsave(&cm_id_priv->lock, flags); 1075 work = get_work(cm_id_priv); 1076 if (!work) { 1077 ret = -ENOMEM; 1078 goto out; 1079 } 1080 1081 INIT_WORK(&work->work, cm_work_handler); 1082 work->cm_id = cm_id_priv; 1083 work->event = *iw_event; 1084 1085 if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST || 1086 work->event.event == IW_CM_EVENT_CONNECT_REPLY) && 1087 work->event.private_data_len) { 1088 ret = copy_private_data(&work->event); 1089 if (ret) { 1090 put_work(work); 1091 goto out; 1092 } 1093 } 1094 1095 refcount_inc(&cm_id_priv->refcount); 1096 if (list_empty(&cm_id_priv->work_list)) { 1097 list_add_tail(&work->list, &cm_id_priv->work_list); 1098 queue_work(iwcm_wq, &work->work); 1099 } else 1100 list_add_tail(&work->list, &cm_id_priv->work_list); 1101out: 1102 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 1103 return ret; 1104} 1105 1106static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv, 1107 struct ib_qp_attr *qp_attr, 1108 int *qp_attr_mask) 1109{ 1110 unsigned long flags; 1111 int ret; 1112 1113 spin_lock_irqsave(&cm_id_priv->lock, flags); 1114 switch (cm_id_priv->state) { 1115 case IW_CM_STATE_IDLE: 1116 case IW_CM_STATE_CONN_SENT: 1117 case IW_CM_STATE_CONN_RECV: 1118 case IW_CM_STATE_ESTABLISHED: 1119 *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS; 1120 qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE| 1121 IB_ACCESS_REMOTE_READ; 1122 ret = 0; 1123 break; 1124 default: 1125 ret = -EINVAL; 1126 break; 1127 } 1128 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 1129 return ret; 1130} 1131 1132static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv, 1133 struct ib_qp_attr *qp_attr, 1134 int *qp_attr_mask) 1135{ 1136 unsigned long flags; 1137 int ret; 1138 1139 spin_lock_irqsave(&cm_id_priv->lock, flags); 1140 switch (cm_id_priv->state) { 1141 case IW_CM_STATE_IDLE: 1142 case IW_CM_STATE_CONN_SENT: 1143 case IW_CM_STATE_CONN_RECV: 1144 case IW_CM_STATE_ESTABLISHED: 1145 *qp_attr_mask = 0; 1146 ret = 0; 1147 break; 1148 default: 1149 ret = -EINVAL; 1150 break; 1151 } 1152 spin_unlock_irqrestore(&cm_id_priv->lock, flags); 1153 return ret; 1154} 1155 1156int iw_cm_init_qp_attr(struct iw_cm_id *cm_id, 1157 struct ib_qp_attr *qp_attr, 1158 int *qp_attr_mask) 1159{ 1160 struct iwcm_id_private *cm_id_priv; 1161 int ret; 1162 1163 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id); 1164 switch (qp_attr->qp_state) { 1165 case IB_QPS_INIT: 1166 case IB_QPS_RTR: 1167 ret = iwcm_init_qp_init_attr(cm_id_priv, 1168 qp_attr, qp_attr_mask); 1169 break; 1170 case IB_QPS_RTS: 1171 ret = iwcm_init_qp_rts_attr(cm_id_priv, 1172 qp_attr, qp_attr_mask); 1173 break; 1174 default: 1175 ret = -EINVAL; 1176 break; 1177 } 1178 return ret; 1179} 1180EXPORT_SYMBOL(iw_cm_init_qp_attr); 1181 1182static int __init iw_cm_init(void) 1183{ 1184 int ret; 1185 1186 ret = iwpm_init(RDMA_NL_IWCM); 1187 if (ret) 1188 return ret; 1189 1190 iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", 0); 1191 if (!iwcm_wq) 1192 goto err_alloc; 1193 1194 iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm", 1195 iwcm_ctl_table); 1196 if (!iwcm_ctl_table_hdr) { 1197 pr_err("iw_cm: couldn't register sysctl paths\n"); 1198 goto err_sysctl; 1199 } 1200 1201 rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table); 1202 return 0; 1203 1204err_sysctl: 1205 destroy_workqueue(iwcm_wq); 1206err_alloc: 1207 iwpm_exit(RDMA_NL_IWCM); 1208 return -ENOMEM; 1209} 1210 1211static void __exit iw_cm_cleanup(void) 1212{ 1213 rdma_nl_unregister(RDMA_NL_IWCM); 1214 unregister_net_sysctl_table(iwcm_ctl_table_hdr); 1215 destroy_workqueue(iwcm_wq); 1216 iwpm_exit(RDMA_NL_IWCM); 1217} 1218 1219MODULE_ALIAS_RDMA_NETLINK(RDMA_NL_IWCM, 2); 1220 1221module_init(iw_cm_init); 1222module_exit(iw_cm_cleanup); 1223