1218 lines · c
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 two10 * licenses. You may choose to be licensed under the terms of the GNU11 * General Public License (GPL) Version 2, available from the file12 * COPYING in the main directory of this source tree, or the13 * OpenIB.org BSD license below:14 *15 * Redistribution and use in source and binary forms, with or16 * without modification, are permitted provided that the following17 * conditions are met:18 *19 * - Redistributions of source code must retain the above20 * copyright notice, this list of conditions and the following21 * disclaimer.22 *23 * - Redistributions in binary form must reproduce the above24 * copyright notice, this list of conditions and the following25 * disclaimer in the documentation and/or other materials26 * 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 OF30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND31 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS32 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN33 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN34 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE35 * 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 else79 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_work118 * elements. The design pre-allocates them based on the cm_id type:119 * LISTENING IDS: Get enough elements preallocated to handle the120 * listen backlog.121 * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE122 * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE123 *124 * Allocating them in connect and listen avoids having to deal125 * with allocation failures on the event upcall from the provider (which126 * 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. If131 * the backlog is exceeded, then no more connection request events will132 * be processed. cm_event_handler() returns -ENOMEM in this case. Its up133 * 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 since137 * 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_first_entry(&cm_id_priv->work_free_list, 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 to187 * iw_cm_event, so the low level driver doesn't have to. Adjust188 * 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 being209 * released, free the cm_id and return 'true'.210 */211static bool 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 true;217 }218 219 return false;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 the282 * 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 <-- CLOSING295 *296 * Block if a passive or active connection is currently being processed. Then297 * process the event as follows:298 * - If we are ESTABLISHED, move to CLOSING and modify the QP state299 * based on the abrupt flag300 * - If the connection is already in the CLOSING or IDLE state, the peer is301 * disconnecting concurrently with us and we've already seen the302 * DISCONNECT event -- ignore the request and return 0303 * - Disconnect on a listening endpoint returns -EINVAL304 */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 else326 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 after339 * 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 else353 ret = iwcm_modify_qp_sqd(qp);354 355 /*356 * If both sides are disconnecting the QP could357 * already be in ERR or SQD states358 */359 ret = 0;360 }361 362 return ret;363}364EXPORT_SYMBOL(iw_cm_disconnect);365 366/*367 * CM_ID <-- DESTROYING368 *369 * Clean up all resources associated with the connection and release370 * the initial reference taken by iw_create_cm_id.371 *372 * Returns true if and only if the last cm_id_priv reference has been dropped.373 */374static bool destroy_cm_id(struct iw_cm_id *cm_id)375{376 struct iwcm_id_private *cm_id_priv;377 struct ib_qp *qp;378 unsigned long flags;379 380 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);381 /*382 * Wait if we're currently in a connect or accept downcall. A383 * listening endpoint should never block here.384 */385 wait_event(cm_id_priv->connect_wait,386 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));387 388 /*389 * Since we're deleting the cm_id, drop any events that390 * might arrive before the last dereference.391 */392 set_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags);393 394 spin_lock_irqsave(&cm_id_priv->lock, flags);395 qp = cm_id_priv->qp;396 cm_id_priv->qp = NULL;397 398 switch (cm_id_priv->state) {399 case IW_CM_STATE_LISTEN:400 cm_id_priv->state = IW_CM_STATE_DESTROYING;401 spin_unlock_irqrestore(&cm_id_priv->lock, flags);402 /* destroy the listening endpoint */403 cm_id->device->ops.iw_destroy_listen(cm_id);404 spin_lock_irqsave(&cm_id_priv->lock, flags);405 break;406 case IW_CM_STATE_ESTABLISHED:407 cm_id_priv->state = IW_CM_STATE_DESTROYING;408 spin_unlock_irqrestore(&cm_id_priv->lock, flags);409 /* Abrupt close of the connection */410 (void)iwcm_modify_qp_err(qp);411 spin_lock_irqsave(&cm_id_priv->lock, flags);412 break;413 case IW_CM_STATE_IDLE:414 case IW_CM_STATE_CLOSING:415 cm_id_priv->state = IW_CM_STATE_DESTROYING;416 break;417 case IW_CM_STATE_CONN_RECV:418 /*419 * App called destroy before/without calling accept after420 * receiving connection request event notification or421 * returned non zero from the event callback function.422 * In either case, must tell the provider to reject.423 */424 cm_id_priv->state = IW_CM_STATE_DESTROYING;425 spin_unlock_irqrestore(&cm_id_priv->lock, flags);426 cm_id->device->ops.iw_reject(cm_id, NULL, 0);427 spin_lock_irqsave(&cm_id_priv->lock, flags);428 break;429 case IW_CM_STATE_CONN_SENT:430 case IW_CM_STATE_DESTROYING:431 default:432 BUG();433 break;434 }435 spin_unlock_irqrestore(&cm_id_priv->lock, flags);436 if (qp)437 cm_id_priv->id.device->ops.iw_rem_ref(qp);438 439 if (cm_id->mapped) {440 iwpm_remove_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr);441 iwpm_remove_mapping(&cm_id->local_addr, RDMA_NL_IWCM);442 }443 444 return iwcm_deref_id(cm_id_priv);445}446 447/*448 * This function is only called by the application thread and cannot449 * be called by the event thread. The function will wait for all450 * references to be released on the cm_id and then kfree the cm_id451 * object.452 */453void iw_destroy_cm_id(struct iw_cm_id *cm_id)454{455 if (!destroy_cm_id(cm_id))456 flush_workqueue(iwcm_wq);457}458EXPORT_SYMBOL(iw_destroy_cm_id);459 460/**461 * iw_cm_check_wildcard - If IP address is 0 then use original462 * @pm_addr: sockaddr containing the ip to check for wildcard463 * @cm_addr: sockaddr containing the actual IP address464 * @cm_outaddr: sockaddr to set IP addr which leaving port465 *466 * Checks the pm_addr for wildcard and then sets cm_outaddr's467 * IP to the actual (cm_addr).468 */469static void iw_cm_check_wildcard(struct sockaddr_storage *pm_addr,470 struct sockaddr_storage *cm_addr,471 struct sockaddr_storage *cm_outaddr)472{473 if (pm_addr->ss_family == AF_INET) {474 struct sockaddr_in *pm4_addr = (struct sockaddr_in *)pm_addr;475 476 if (pm4_addr->sin_addr.s_addr == htonl(INADDR_ANY)) {477 struct sockaddr_in *cm4_addr =478 (struct sockaddr_in *)cm_addr;479 struct sockaddr_in *cm4_outaddr =480 (struct sockaddr_in *)cm_outaddr;481 482 cm4_outaddr->sin_addr = cm4_addr->sin_addr;483 }484 } else {485 struct sockaddr_in6 *pm6_addr = (struct sockaddr_in6 *)pm_addr;486 487 if (ipv6_addr_type(&pm6_addr->sin6_addr) == IPV6_ADDR_ANY) {488 struct sockaddr_in6 *cm6_addr =489 (struct sockaddr_in6 *)cm_addr;490 struct sockaddr_in6 *cm6_outaddr =491 (struct sockaddr_in6 *)cm_outaddr;492 493 cm6_outaddr->sin6_addr = cm6_addr->sin6_addr;494 }495 }496}497 498/**499 * iw_cm_map - Use portmapper to map the ports500 * @cm_id: connection manager pointer501 * @active: Indicates the active side when true502 * returns nonzero for error only if iwpm_create_mapinfo() fails503 *504 * Tries to add a mapping for a port using the Portmapper. If505 * successful in mapping the IP/Port it will check the remote506 * mapped IP address for a wildcard IP address and replace the507 * zero IP address with the remote_addr.508 */509static int iw_cm_map(struct iw_cm_id *cm_id, bool active)510{511 const char *devname = dev_name(&cm_id->device->dev);512 const char *ifname = cm_id->device->iw_ifname;513 struct iwpm_dev_data pm_reg_msg = {};514 struct iwpm_sa_data pm_msg;515 int status;516 517 if (strlen(devname) >= sizeof(pm_reg_msg.dev_name) ||518 strlen(ifname) >= sizeof(pm_reg_msg.if_name))519 return -EINVAL;520 521 cm_id->m_local_addr = cm_id->local_addr;522 cm_id->m_remote_addr = cm_id->remote_addr;523 524 strcpy(pm_reg_msg.dev_name, devname);525 strcpy(pm_reg_msg.if_name, ifname);526 527 if (iwpm_register_pid(&pm_reg_msg, RDMA_NL_IWCM) ||528 !iwpm_valid_pid())529 return 0;530 531 cm_id->mapped = true;532 pm_msg.loc_addr = cm_id->local_addr;533 pm_msg.rem_addr = cm_id->remote_addr;534 pm_msg.flags = (cm_id->device->iw_driver_flags & IW_F_NO_PORT_MAP) ?535 IWPM_FLAGS_NO_PORT_MAP : 0;536 if (active)537 status = iwpm_add_and_query_mapping(&pm_msg,538 RDMA_NL_IWCM);539 else540 status = iwpm_add_mapping(&pm_msg, RDMA_NL_IWCM);541 542 if (!status) {543 cm_id->m_local_addr = pm_msg.mapped_loc_addr;544 if (active) {545 cm_id->m_remote_addr = pm_msg.mapped_rem_addr;546 iw_cm_check_wildcard(&pm_msg.mapped_rem_addr,547 &cm_id->remote_addr,548 &cm_id->m_remote_addr);549 }550 }551 552 return iwpm_create_mapinfo(&cm_id->local_addr,553 &cm_id->m_local_addr,554 RDMA_NL_IWCM, pm_msg.flags);555}556 557/*558 * CM_ID <-- LISTEN559 *560 * Start listening for connect requests. Generates one CONNECT_REQUEST561 * event for each inbound connect request.562 */563int iw_cm_listen(struct iw_cm_id *cm_id, int backlog)564{565 struct iwcm_id_private *cm_id_priv;566 unsigned long flags;567 int ret;568 569 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);570 571 if (!backlog)572 backlog = default_backlog;573 574 ret = alloc_work_entries(cm_id_priv, backlog);575 if (ret)576 return ret;577 578 spin_lock_irqsave(&cm_id_priv->lock, flags);579 switch (cm_id_priv->state) {580 case IW_CM_STATE_IDLE:581 cm_id_priv->state = IW_CM_STATE_LISTEN;582 spin_unlock_irqrestore(&cm_id_priv->lock, flags);583 ret = iw_cm_map(cm_id, false);584 if (!ret)585 ret = cm_id->device->ops.iw_create_listen(cm_id,586 backlog);587 if (ret)588 cm_id_priv->state = IW_CM_STATE_IDLE;589 spin_lock_irqsave(&cm_id_priv->lock, flags);590 break;591 default:592 ret = -EINVAL;593 }594 spin_unlock_irqrestore(&cm_id_priv->lock, flags);595 596 return ret;597}598EXPORT_SYMBOL(iw_cm_listen);599 600/*601 * CM_ID <-- IDLE602 *603 * Rejects an inbound connection request. No events are generated.604 */605int iw_cm_reject(struct iw_cm_id *cm_id,606 const void *private_data,607 u8 private_data_len)608{609 struct iwcm_id_private *cm_id_priv;610 unsigned long flags;611 int ret;612 613 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);614 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);615 616 spin_lock_irqsave(&cm_id_priv->lock, flags);617 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {618 spin_unlock_irqrestore(&cm_id_priv->lock, flags);619 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);620 wake_up_all(&cm_id_priv->connect_wait);621 return -EINVAL;622 }623 cm_id_priv->state = IW_CM_STATE_IDLE;624 spin_unlock_irqrestore(&cm_id_priv->lock, flags);625 626 ret = cm_id->device->ops.iw_reject(cm_id, private_data,627 private_data_len);628 629 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);630 wake_up_all(&cm_id_priv->connect_wait);631 632 return ret;633}634EXPORT_SYMBOL(iw_cm_reject);635 636/*637 * CM_ID <-- ESTABLISHED638 *639 * Accepts an inbound connection request and generates an ESTABLISHED640 * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block641 * until the ESTABLISHED event is received from the provider.642 */643int iw_cm_accept(struct iw_cm_id *cm_id,644 struct iw_cm_conn_param *iw_param)645{646 struct iwcm_id_private *cm_id_priv;647 struct ib_qp *qp;648 unsigned long flags;649 int ret;650 651 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);652 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);653 654 spin_lock_irqsave(&cm_id_priv->lock, flags);655 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {656 spin_unlock_irqrestore(&cm_id_priv->lock, flags);657 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);658 wake_up_all(&cm_id_priv->connect_wait);659 return -EINVAL;660 }661 /* Get the ib_qp given the QPN */662 qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn);663 if (!qp) {664 spin_unlock_irqrestore(&cm_id_priv->lock, flags);665 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);666 wake_up_all(&cm_id_priv->connect_wait);667 return -EINVAL;668 }669 cm_id->device->ops.iw_add_ref(qp);670 cm_id_priv->qp = qp;671 spin_unlock_irqrestore(&cm_id_priv->lock, flags);672 673 ret = cm_id->device->ops.iw_accept(cm_id, iw_param);674 if (ret) {675 /* An error on accept precludes provider events */676 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);677 cm_id_priv->state = IW_CM_STATE_IDLE;678 spin_lock_irqsave(&cm_id_priv->lock, flags);679 qp = cm_id_priv->qp;680 cm_id_priv->qp = NULL;681 spin_unlock_irqrestore(&cm_id_priv->lock, flags);682 if (qp)683 cm_id->device->ops.iw_rem_ref(qp);684 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);685 wake_up_all(&cm_id_priv->connect_wait);686 }687 688 return ret;689}690EXPORT_SYMBOL(iw_cm_accept);691 692/*693 * Active Side: CM_ID <-- CONN_SENT694 *695 * If successful, results in the generation of a CONNECT_REPLY696 * event. iw_cm_disconnect and iw_cm_destroy will block until the697 * CONNECT_REPLY event is received from the provider.698 */699int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param)700{701 struct iwcm_id_private *cm_id_priv;702 int ret;703 unsigned long flags;704 struct ib_qp *qp = NULL;705 706 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);707 708 ret = alloc_work_entries(cm_id_priv, 4);709 if (ret)710 return ret;711 712 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);713 spin_lock_irqsave(&cm_id_priv->lock, flags);714 715 if (cm_id_priv->state != IW_CM_STATE_IDLE) {716 ret = -EINVAL;717 goto err;718 }719 720 /* Get the ib_qp given the QPN */721 qp = cm_id->device->ops.iw_get_qp(cm_id->device, iw_param->qpn);722 if (!qp) {723 ret = -EINVAL;724 goto err;725 }726 cm_id->device->ops.iw_add_ref(qp);727 cm_id_priv->qp = qp;728 cm_id_priv->state = IW_CM_STATE_CONN_SENT;729 spin_unlock_irqrestore(&cm_id_priv->lock, flags);730 731 ret = iw_cm_map(cm_id, true);732 if (!ret)733 ret = cm_id->device->ops.iw_connect(cm_id, iw_param);734 if (!ret)735 return 0; /* success */736 737 spin_lock_irqsave(&cm_id_priv->lock, flags);738 qp = cm_id_priv->qp;739 cm_id_priv->qp = NULL;740 cm_id_priv->state = IW_CM_STATE_IDLE;741err:742 spin_unlock_irqrestore(&cm_id_priv->lock, flags);743 if (qp)744 cm_id->device->ops.iw_rem_ref(qp);745 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);746 wake_up_all(&cm_id_priv->connect_wait);747 return ret;748}749EXPORT_SYMBOL(iw_cm_connect);750 751/*752 * Passive Side: new CM_ID <-- CONN_RECV753 *754 * Handles an inbound connect request. The function creates a new755 * iw_cm_id to represent the new connection and inherits the client756 * callback function and other attributes from the listening parent.757 *758 * The work item contains a pointer to the listen_cm_id and the event. The759 * listen_cm_id contains the client cm_handler, context and760 * device. These are copied when the device is cloned. The event761 * contains the new four tuple.762 *763 * An error on the child should not affect the parent, so this764 * function does not return a value.765 */766static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv,767 struct iw_cm_event *iw_event)768{769 unsigned long flags;770 struct iw_cm_id *cm_id;771 struct iwcm_id_private *cm_id_priv;772 int ret;773 774 /*775 * The provider should never generate a connection request776 * event with a bad status.777 */778 BUG_ON(iw_event->status);779 780 cm_id = iw_create_cm_id(listen_id_priv->id.device,781 listen_id_priv->id.cm_handler,782 listen_id_priv->id.context);783 /* If the cm_id could not be created, ignore the request */784 if (IS_ERR(cm_id))785 goto out;786 787 cm_id->provider_data = iw_event->provider_data;788 cm_id->m_local_addr = iw_event->local_addr;789 cm_id->m_remote_addr = iw_event->remote_addr;790 cm_id->local_addr = listen_id_priv->id.local_addr;791 792 ret = iwpm_get_remote_info(&listen_id_priv->id.m_local_addr,793 &iw_event->remote_addr,794 &cm_id->remote_addr,795 RDMA_NL_IWCM);796 if (ret) {797 cm_id->remote_addr = iw_event->remote_addr;798 } else {799 iw_cm_check_wildcard(&listen_id_priv->id.m_local_addr,800 &iw_event->local_addr,801 &cm_id->local_addr);802 iw_event->local_addr = cm_id->local_addr;803 iw_event->remote_addr = cm_id->remote_addr;804 }805 806 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);807 cm_id_priv->state = IW_CM_STATE_CONN_RECV;808 809 /*810 * We could be destroying the listening id. If so, ignore this811 * upcall.812 */813 spin_lock_irqsave(&listen_id_priv->lock, flags);814 if (listen_id_priv->state != IW_CM_STATE_LISTEN) {815 spin_unlock_irqrestore(&listen_id_priv->lock, flags);816 iw_cm_reject(cm_id, NULL, 0);817 iw_destroy_cm_id(cm_id);818 goto out;819 }820 spin_unlock_irqrestore(&listen_id_priv->lock, flags);821 822 ret = alloc_work_entries(cm_id_priv, 3);823 if (ret) {824 iw_cm_reject(cm_id, NULL, 0);825 iw_destroy_cm_id(cm_id);826 goto out;827 }828 829 /* Call the client CM handler */830 ret = cm_id->cm_handler(cm_id, iw_event);831 if (ret) {832 iw_cm_reject(cm_id, NULL, 0);833 iw_destroy_cm_id(cm_id);834 }835 836out:837 if (iw_event->private_data_len)838 kfree(iw_event->private_data);839}840 841/*842 * Passive Side: CM_ID <-- ESTABLISHED843 *844 * The provider generated an ESTABLISHED event which means that845 * the MPA negotion has completed successfully and we are now in MPA846 * FPDU mode.847 *848 * This event can only be received in the CONN_RECV state. If the849 * remote peer closed, the ESTABLISHED event would be received followed850 * by the CLOSE event. If the app closes, it will block until we wake851 * it up after processing this event.852 */853static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv,854 struct iw_cm_event *iw_event)855{856 unsigned long flags;857 int ret;858 859 spin_lock_irqsave(&cm_id_priv->lock, flags);860 861 /*862 * We clear the CONNECT_WAIT bit here to allow the callback863 * function to call iw_cm_disconnect. Calling iw_destroy_cm_id864 * from a callback handler is not allowed.865 */866 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);867 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);868 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;869 spin_unlock_irqrestore(&cm_id_priv->lock, flags);870 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);871 wake_up_all(&cm_id_priv->connect_wait);872 873 return ret;874}875 876/*877 * Active Side: CM_ID <-- ESTABLISHED878 *879 * The app has called connect and is waiting for the established event to880 * post it's requests to the server. This event will wake up anyone881 * blocked in iw_cm_disconnect or iw_destroy_id.882 */883static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv,884 struct iw_cm_event *iw_event)885{886 struct ib_qp *qp = NULL;887 unsigned long flags;888 int ret;889 890 spin_lock_irqsave(&cm_id_priv->lock, flags);891 /*892 * Clear the connect wait bit so a callback function calling893 * iw_cm_disconnect will not wait and deadlock this thread894 */895 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);896 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT);897 if (iw_event->status == 0) {898 cm_id_priv->id.m_local_addr = iw_event->local_addr;899 cm_id_priv->id.m_remote_addr = iw_event->remote_addr;900 iw_event->local_addr = cm_id_priv->id.local_addr;901 iw_event->remote_addr = cm_id_priv->id.remote_addr;902 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;903 } else {904 /* REJECTED or RESET */905 qp = cm_id_priv->qp;906 cm_id_priv->qp = NULL;907 cm_id_priv->state = IW_CM_STATE_IDLE;908 }909 spin_unlock_irqrestore(&cm_id_priv->lock, flags);910 if (qp)911 cm_id_priv->id.device->ops.iw_rem_ref(qp);912 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);913 914 if (iw_event->private_data_len)915 kfree(iw_event->private_data);916 917 /* Wake up waiters on connect complete */918 wake_up_all(&cm_id_priv->connect_wait);919 920 return ret;921}922 923/*924 * CM_ID <-- CLOSING925 *926 * If in the ESTABLISHED state, move to CLOSING.927 */928static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv,929 struct iw_cm_event *iw_event)930{931 unsigned long flags;932 933 spin_lock_irqsave(&cm_id_priv->lock, flags);934 if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED)935 cm_id_priv->state = IW_CM_STATE_CLOSING;936 spin_unlock_irqrestore(&cm_id_priv->lock, flags);937}938 939/*940 * CM_ID <-- IDLE941 *942 * If in the ESTBLISHED or CLOSING states, the QP will have have been943 * moved by the provider to the ERR state. Disassociate the CM_ID from944 * the QP, move to IDLE, and remove the 'connected' reference.945 *946 * If in some other state, the cm_id was destroyed asynchronously.947 * This is the last reference that will result in waking up948 * the app thread blocked in iw_destroy_cm_id.949 */950static int cm_close_handler(struct iwcm_id_private *cm_id_priv,951 struct iw_cm_event *iw_event)952{953 struct ib_qp *qp;954 unsigned long flags;955 int ret = 0, notify_event = 0;956 spin_lock_irqsave(&cm_id_priv->lock, flags);957 qp = cm_id_priv->qp;958 cm_id_priv->qp = NULL;959 960 switch (cm_id_priv->state) {961 case IW_CM_STATE_ESTABLISHED:962 case IW_CM_STATE_CLOSING:963 cm_id_priv->state = IW_CM_STATE_IDLE;964 notify_event = 1;965 break;966 case IW_CM_STATE_DESTROYING:967 break;968 default:969 BUG();970 }971 spin_unlock_irqrestore(&cm_id_priv->lock, flags);972 973 if (qp)974 cm_id_priv->id.device->ops.iw_rem_ref(qp);975 if (notify_event)976 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);977 return ret;978}979 980static int process_event(struct iwcm_id_private *cm_id_priv,981 struct iw_cm_event *iw_event)982{983 int ret = 0;984 985 switch (iw_event->event) {986 case IW_CM_EVENT_CONNECT_REQUEST:987 cm_conn_req_handler(cm_id_priv, iw_event);988 break;989 case IW_CM_EVENT_CONNECT_REPLY:990 ret = cm_conn_rep_handler(cm_id_priv, iw_event);991 break;992 case IW_CM_EVENT_ESTABLISHED:993 ret = cm_conn_est_handler(cm_id_priv, iw_event);994 break;995 case IW_CM_EVENT_DISCONNECT:996 cm_disconnect_handler(cm_id_priv, iw_event);997 break;998 case IW_CM_EVENT_CLOSE:999 ret = cm_close_handler(cm_id_priv, iw_event);1000 break;1001 default:1002 BUG();1003 }1004 1005 return ret;1006}1007 1008/*1009 * Process events on the work_list for the cm_id. If the callback1010 * function requests that the cm_id be deleted, a flag is set in the1011 * cm_id flags to indicate that when the last reference is1012 * removed, the cm_id is to be destroyed. This is necessary to1013 * distinguish between an object that will be destroyed by the app1014 * thread asleep on the destroy_comp list vs. an object destroyed1015 * here synchronously when the last reference is removed.1016 */1017static void cm_work_handler(struct work_struct *_work)1018{1019 struct iwcm_work *work = container_of(_work, struct iwcm_work, work);1020 struct iw_cm_event levent;1021 struct iwcm_id_private *cm_id_priv = work->cm_id;1022 unsigned long flags;1023 int ret = 0;1024 1025 spin_lock_irqsave(&cm_id_priv->lock, flags);1026 while (!list_empty(&cm_id_priv->work_list)) {1027 work = list_first_entry(&cm_id_priv->work_list,1028 struct iwcm_work, list);1029 list_del_init(&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 WARN_ON_ONCE(destroy_cm_id(&cm_id_priv->id));1038 } else1039 pr_debug("dropping event %d\n", levent.event);1040 if (iwcm_deref_id(cm_id_priv))1041 return;1042 spin_lock_irqsave(&cm_id_priv->lock, flags);1043 }1044 spin_unlock_irqrestore(&cm_id_priv->lock, flags);1045}1046 1047/*1048 * This function is called on interrupt context. Schedule events on1049 * the iwcm_wq thread to allow callback functions to downcall into1050 * the CM and/or block. Events are queued to a per-CM_ID1051 * work_list. If this is the first event on the work_list, the work1052 * element is also queued on the iwcm_wq thread.1053 *1054 * Each event holds a reference on the cm_id. Until the last posted1055 * event has been delivered and processed, the cm_id cannot be1056 * deleted.1057 *1058 * Returns:1059 * 0 - the event was handled.1060 * -ENOMEM - the event was not handled due to lack of resources.1061 */1062static int cm_event_handler(struct iw_cm_id *cm_id,1063 struct iw_cm_event *iw_event)1064{1065 struct iwcm_work *work;1066 struct iwcm_id_private *cm_id_priv;1067 unsigned long flags;1068 int ret = 0;1069 1070 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);1071 1072 spin_lock_irqsave(&cm_id_priv->lock, flags);1073 work = get_work(cm_id_priv);1074 if (!work) {1075 ret = -ENOMEM;1076 goto out;1077 }1078 1079 INIT_WORK(&work->work, cm_work_handler);1080 work->cm_id = cm_id_priv;1081 work->event = *iw_event;1082 1083 if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST ||1084 work->event.event == IW_CM_EVENT_CONNECT_REPLY) &&1085 work->event.private_data_len) {1086 ret = copy_private_data(&work->event);1087 if (ret) {1088 put_work(work);1089 goto out;1090 }1091 }1092 1093 refcount_inc(&cm_id_priv->refcount);1094 list_add_tail(&work->list, &cm_id_priv->work_list);1095 queue_work(iwcm_wq, &work->work);1096out:1097 spin_unlock_irqrestore(&cm_id_priv->lock, flags);1098 return ret;1099}1100 1101static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv,1102 struct ib_qp_attr *qp_attr,1103 int *qp_attr_mask)1104{1105 unsigned long flags;1106 int ret;1107 1108 spin_lock_irqsave(&cm_id_priv->lock, flags);1109 switch (cm_id_priv->state) {1110 case IW_CM_STATE_IDLE:1111 case IW_CM_STATE_CONN_SENT:1112 case IW_CM_STATE_CONN_RECV:1113 case IW_CM_STATE_ESTABLISHED:1114 *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS;1115 qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE|1116 IB_ACCESS_REMOTE_READ;1117 ret = 0;1118 break;1119 default:1120 ret = -EINVAL;1121 break;1122 }1123 spin_unlock_irqrestore(&cm_id_priv->lock, flags);1124 return ret;1125}1126 1127static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv,1128 struct ib_qp_attr *qp_attr,1129 int *qp_attr_mask)1130{1131 unsigned long flags;1132 int ret;1133 1134 spin_lock_irqsave(&cm_id_priv->lock, flags);1135 switch (cm_id_priv->state) {1136 case IW_CM_STATE_IDLE:1137 case IW_CM_STATE_CONN_SENT:1138 case IW_CM_STATE_CONN_RECV:1139 case IW_CM_STATE_ESTABLISHED:1140 *qp_attr_mask = 0;1141 ret = 0;1142 break;1143 default:1144 ret = -EINVAL;1145 break;1146 }1147 spin_unlock_irqrestore(&cm_id_priv->lock, flags);1148 return ret;1149}1150 1151int iw_cm_init_qp_attr(struct iw_cm_id *cm_id,1152 struct ib_qp_attr *qp_attr,1153 int *qp_attr_mask)1154{1155 struct iwcm_id_private *cm_id_priv;1156 int ret;1157 1158 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);1159 switch (qp_attr->qp_state) {1160 case IB_QPS_INIT:1161 case IB_QPS_RTR:1162 ret = iwcm_init_qp_init_attr(cm_id_priv,1163 qp_attr, qp_attr_mask);1164 break;1165 case IB_QPS_RTS:1166 ret = iwcm_init_qp_rts_attr(cm_id_priv,1167 qp_attr, qp_attr_mask);1168 break;1169 default:1170 ret = -EINVAL;1171 break;1172 }1173 return ret;1174}1175EXPORT_SYMBOL(iw_cm_init_qp_attr);1176 1177static int __init iw_cm_init(void)1178{1179 int ret;1180 1181 ret = iwpm_init(RDMA_NL_IWCM);1182 if (ret)1183 return ret;1184 1185 iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", WQ_MEM_RECLAIM);1186 if (!iwcm_wq)1187 goto err_alloc;1188 1189 iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm",1190 iwcm_ctl_table);1191 if (!iwcm_ctl_table_hdr) {1192 pr_err("iw_cm: couldn't register sysctl paths\n");1193 goto err_sysctl;1194 }1195 1196 rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table);1197 return 0;1198 1199err_sysctl:1200 destroy_workqueue(iwcm_wq);1201err_alloc:1202 iwpm_exit(RDMA_NL_IWCM);1203 return -ENOMEM;1204}1205 1206static void __exit iw_cm_cleanup(void)1207{1208 rdma_nl_unregister(RDMA_NL_IWCM);1209 unregister_net_sysctl_table(iwcm_ctl_table_hdr);1210 destroy_workqueue(iwcm_wq);1211 iwpm_exit(RDMA_NL_IWCM);1212}1213 1214MODULE_ALIAS_RDMA_NETLINK(RDMA_NL_IWCM, 2);1215 1216module_init(iw_cm_init);1217module_exit(iw_cm_cleanup);1218