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.
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:
15 * Redistribution and use in source and binary forms, with or
16 * without modification, are permitted provided that the following
19 * - Redistributions of source code must retain the above
20 * copyright notice, this list of conditions and the following
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.
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
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>
51 #include <rdma/iw_cm.h>
52 #include <rdma/ib_addr.h>
53 #include <rdma/iw_portmap.h>
54 #include <rdma/rdma_netlink.h>
58 MODULE_AUTHOR("Tom Tucker");
59 MODULE_DESCRIPTION("iWARP CM");
60 MODULE_LICENSE("Dual BSD/GPL");
62 static const char * const iwcm_rej_reason_strs[] = {
63 [ECONNRESET] = "reset by remote host",
64 [ECONNREFUSED] = "refused by remote application",
65 [ETIMEDOUT] = "setup timeout",
68 const char *__attribute_const__ iwcm_reject_msg(int reason)
72 /* iWARP uses negative errnos */
75 if (index < ARRAY_SIZE(iwcm_rej_reason_strs) &&
76 iwcm_rej_reason_strs[index])
77 return iwcm_rej_reason_strs[index];
79 return "unrecognized reason";
81 EXPORT_SYMBOL(iwcm_reject_msg);
83 static struct rdma_nl_cbs iwcm_nl_cb_table[] = {
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}
93 static struct workqueue_struct *iwcm_wq;
95 struct work_struct work;
96 struct iwcm_id_private *cm_id;
97 struct list_head list;
98 struct iw_cm_event event;
99 struct list_head free_list;
102 static unsigned int default_backlog = 256;
104 static struct ctl_table_header *iwcm_ctl_table_hdr;
105 static struct ctl_table iwcm_ctl_table[] = {
107 .procname = "default_backlog",
108 .data = &default_backlog,
109 .maxlen = sizeof(default_backlog),
111 .proc_handler = proc_dointvec,
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
121 * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE
122 * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE
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).
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.
140 static struct iwcm_work *get_work(struct iwcm_id_private *cm_id_priv)
142 struct iwcm_work *work;
144 if (list_empty(&cm_id_priv->work_free_list))
146 work = list_entry(cm_id_priv->work_free_list.next, struct iwcm_work,
148 list_del_init(&work->free_list);
152 static void put_work(struct iwcm_work *work)
154 list_add(&work->free_list, &work->cm_id->work_free_list);
157 static void dealloc_work_entries(struct iwcm_id_private *cm_id_priv)
159 struct list_head *e, *tmp;
161 list_for_each_safe(e, tmp, &cm_id_priv->work_free_list)
162 kfree(list_entry(e, struct iwcm_work, free_list));
165 static int alloc_work_entries(struct iwcm_id_private *cm_id_priv, int count)
167 struct iwcm_work *work;
169 BUG_ON(!list_empty(&cm_id_priv->work_free_list));
171 work = kmalloc(sizeof(struct iwcm_work), GFP_KERNEL);
173 dealloc_work_entries(cm_id_priv);
176 work->cm_id = cm_id_priv;
177 INIT_LIST_HEAD(&work->list);
184 * Save private data from incoming connection requests to
185 * iw_cm_event, so the low level driver doesn't have to. Adjust
186 * the event ptr to point to the local copy.
188 static int copy_private_data(struct iw_cm_event *event)
192 p = kmemdup(event->private_data, event->private_data_len, GFP_ATOMIC);
195 event->private_data = p;
199 static void free_cm_id(struct iwcm_id_private *cm_id_priv)
201 dealloc_work_entries(cm_id_priv);
206 * Release a reference on cm_id. If the last reference is being
207 * released, free the cm_id and return 1.
209 static int iwcm_deref_id(struct iwcm_id_private *cm_id_priv)
211 BUG_ON(atomic_read(&cm_id_priv->refcount)==0);
212 if (atomic_dec_and_test(&cm_id_priv->refcount)) {
213 BUG_ON(!list_empty(&cm_id_priv->work_list));
214 free_cm_id(cm_id_priv);
221 static void add_ref(struct iw_cm_id *cm_id)
223 struct iwcm_id_private *cm_id_priv;
224 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
225 atomic_inc(&cm_id_priv->refcount);
228 static void rem_ref(struct iw_cm_id *cm_id)
230 struct iwcm_id_private *cm_id_priv;
232 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
234 (void)iwcm_deref_id(cm_id_priv);
237 static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *event);
239 struct iw_cm_id *iw_create_cm_id(struct ib_device *device,
240 iw_cm_handler cm_handler,
243 struct iwcm_id_private *cm_id_priv;
245 cm_id_priv = kzalloc(sizeof(*cm_id_priv), GFP_KERNEL);
247 return ERR_PTR(-ENOMEM);
249 cm_id_priv->state = IW_CM_STATE_IDLE;
250 cm_id_priv->id.device = device;
251 cm_id_priv->id.cm_handler = cm_handler;
252 cm_id_priv->id.context = context;
253 cm_id_priv->id.event_handler = cm_event_handler;
254 cm_id_priv->id.add_ref = add_ref;
255 cm_id_priv->id.rem_ref = rem_ref;
256 spin_lock_init(&cm_id_priv->lock);
257 atomic_set(&cm_id_priv->refcount, 1);
258 init_waitqueue_head(&cm_id_priv->connect_wait);
259 init_completion(&cm_id_priv->destroy_comp);
260 INIT_LIST_HEAD(&cm_id_priv->work_list);
261 INIT_LIST_HEAD(&cm_id_priv->work_free_list);
263 return &cm_id_priv->id;
265 EXPORT_SYMBOL(iw_create_cm_id);
268 static int iwcm_modify_qp_err(struct ib_qp *qp)
270 struct ib_qp_attr qp_attr;
275 qp_attr.qp_state = IB_QPS_ERR;
276 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
280 * This is really the RDMAC CLOSING state. It is most similar to the
283 static int iwcm_modify_qp_sqd(struct ib_qp *qp)
285 struct ib_qp_attr qp_attr;
288 qp_attr.qp_state = IB_QPS_SQD;
289 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
295 * Block if a passive or active connection is currently being processed. Then
296 * process the event as follows:
297 * - If we are ESTABLISHED, move to CLOSING and modify the QP state
298 * based on the abrupt flag
299 * - If the connection is already in the CLOSING or IDLE state, the peer is
300 * disconnecting concurrently with us and we've already seen the
301 * DISCONNECT event -- ignore the request and return 0
302 * - Disconnect on a listening endpoint returns -EINVAL
304 int iw_cm_disconnect(struct iw_cm_id *cm_id, int abrupt)
306 struct iwcm_id_private *cm_id_priv;
309 struct ib_qp *qp = NULL;
311 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
312 /* Wait if we're currently in a connect or accept downcall */
313 wait_event(cm_id_priv->connect_wait,
314 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
316 spin_lock_irqsave(&cm_id_priv->lock, flags);
317 switch (cm_id_priv->state) {
318 case IW_CM_STATE_ESTABLISHED:
319 cm_id_priv->state = IW_CM_STATE_CLOSING;
321 /* QP could be <nul> for user-mode client */
327 case IW_CM_STATE_LISTEN:
330 case IW_CM_STATE_CLOSING:
331 /* remote peer closed first */
332 case IW_CM_STATE_IDLE:
333 /* accept or connect returned !0 */
335 case IW_CM_STATE_CONN_RECV:
337 * App called disconnect before/without calling accept after
338 * connect_request event delivered.
341 case IW_CM_STATE_CONN_SENT:
342 /* Can only get here if wait above fails */
346 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
350 ret = iwcm_modify_qp_err(qp);
352 ret = iwcm_modify_qp_sqd(qp);
355 * If both sides are disconnecting the QP could
356 * already be in ERR or SQD states
363 EXPORT_SYMBOL(iw_cm_disconnect);
366 * CM_ID <-- DESTROYING
368 * Clean up all resources associated with the connection and release
369 * the initial reference taken by iw_create_cm_id.
371 static void destroy_cm_id(struct iw_cm_id *cm_id)
373 struct iwcm_id_private *cm_id_priv;
376 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
378 * Wait if we're currently in a connect or accept downcall. A
379 * listening endpoint should never block here.
381 wait_event(cm_id_priv->connect_wait,
382 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
385 * Since we're deleting the cm_id, drop any events that
386 * might arrive before the last dereference.
388 set_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags);
390 spin_lock_irqsave(&cm_id_priv->lock, flags);
391 switch (cm_id_priv->state) {
392 case IW_CM_STATE_LISTEN:
393 cm_id_priv->state = IW_CM_STATE_DESTROYING;
394 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
395 /* destroy the listening endpoint */
396 cm_id->device->iwcm->destroy_listen(cm_id);
397 spin_lock_irqsave(&cm_id_priv->lock, flags);
399 case IW_CM_STATE_ESTABLISHED:
400 cm_id_priv->state = IW_CM_STATE_DESTROYING;
401 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
402 /* Abrupt close of the connection */
403 (void)iwcm_modify_qp_err(cm_id_priv->qp);
404 spin_lock_irqsave(&cm_id_priv->lock, flags);
406 case IW_CM_STATE_IDLE:
407 case IW_CM_STATE_CLOSING:
408 cm_id_priv->state = IW_CM_STATE_DESTROYING;
410 case IW_CM_STATE_CONN_RECV:
412 * App called destroy before/without calling accept after
413 * receiving connection request event notification or
414 * returned non zero from the event callback function.
415 * In either case, must tell the provider to reject.
417 cm_id_priv->state = IW_CM_STATE_DESTROYING;
418 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
419 cm_id->device->iwcm->reject(cm_id, NULL, 0);
420 spin_lock_irqsave(&cm_id_priv->lock, flags);
422 case IW_CM_STATE_CONN_SENT:
423 case IW_CM_STATE_DESTROYING:
428 if (cm_id_priv->qp) {
429 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
430 cm_id_priv->qp = NULL;
432 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
435 iwpm_remove_mapinfo(&cm_id->local_addr, &cm_id->m_local_addr);
436 iwpm_remove_mapping(&cm_id->local_addr, RDMA_NL_IWCM);
439 (void)iwcm_deref_id(cm_id_priv);
443 * This function is only called by the application thread and cannot
444 * be called by the event thread. The function will wait for all
445 * references to be released on the cm_id and then kfree the cm_id
448 void iw_destroy_cm_id(struct iw_cm_id *cm_id)
450 destroy_cm_id(cm_id);
452 EXPORT_SYMBOL(iw_destroy_cm_id);
455 * iw_cm_check_wildcard - If IP address is 0 then use original
456 * @pm_addr: sockaddr containing the ip to check for wildcard
457 * @cm_addr: sockaddr containing the actual IP address
458 * @cm_outaddr: sockaddr to set IP addr which leaving port
460 * Checks the pm_addr for wildcard and then sets cm_outaddr's
461 * IP to the actual (cm_addr).
463 static void iw_cm_check_wildcard(struct sockaddr_storage *pm_addr,
464 struct sockaddr_storage *cm_addr,
465 struct sockaddr_storage *cm_outaddr)
467 if (pm_addr->ss_family == AF_INET) {
468 struct sockaddr_in *pm4_addr = (struct sockaddr_in *)pm_addr;
470 if (pm4_addr->sin_addr.s_addr == htonl(INADDR_ANY)) {
471 struct sockaddr_in *cm4_addr =
472 (struct sockaddr_in *)cm_addr;
473 struct sockaddr_in *cm4_outaddr =
474 (struct sockaddr_in *)cm_outaddr;
476 cm4_outaddr->sin_addr = cm4_addr->sin_addr;
479 struct sockaddr_in6 *pm6_addr = (struct sockaddr_in6 *)pm_addr;
481 if (ipv6_addr_type(&pm6_addr->sin6_addr) == IPV6_ADDR_ANY) {
482 struct sockaddr_in6 *cm6_addr =
483 (struct sockaddr_in6 *)cm_addr;
484 struct sockaddr_in6 *cm6_outaddr =
485 (struct sockaddr_in6 *)cm_outaddr;
487 cm6_outaddr->sin6_addr = cm6_addr->sin6_addr;
493 * iw_cm_map - Use portmapper to map the ports
494 * @cm_id: connection manager pointer
495 * @active: Indicates the active side when true
496 * returns nonzero for error only if iwpm_create_mapinfo() fails
498 * Tries to add a mapping for a port using the Portmapper. If
499 * successful in mapping the IP/Port it will check the remote
500 * mapped IP address for a wildcard IP address and replace the
501 * zero IP address with the remote_addr.
503 static int iw_cm_map(struct iw_cm_id *cm_id, bool active)
505 struct iwpm_dev_data pm_reg_msg;
506 struct iwpm_sa_data pm_msg;
509 cm_id->m_local_addr = cm_id->local_addr;
510 cm_id->m_remote_addr = cm_id->remote_addr;
512 memcpy(pm_reg_msg.dev_name, cm_id->device->name,
513 sizeof(pm_reg_msg.dev_name));
514 memcpy(pm_reg_msg.if_name, cm_id->device->iwcm->ifname,
515 sizeof(pm_reg_msg.if_name));
517 if (iwpm_register_pid(&pm_reg_msg, RDMA_NL_IWCM) ||
521 cm_id->mapped = true;
522 pm_msg.loc_addr = cm_id->local_addr;
523 pm_msg.rem_addr = cm_id->remote_addr;
525 status = iwpm_add_and_query_mapping(&pm_msg,
528 status = iwpm_add_mapping(&pm_msg, RDMA_NL_IWCM);
531 cm_id->m_local_addr = pm_msg.mapped_loc_addr;
533 cm_id->m_remote_addr = pm_msg.mapped_rem_addr;
534 iw_cm_check_wildcard(&pm_msg.mapped_rem_addr,
536 &cm_id->m_remote_addr);
540 return iwpm_create_mapinfo(&cm_id->local_addr,
541 &cm_id->m_local_addr,
548 * Start listening for connect requests. Generates one CONNECT_REQUEST
549 * event for each inbound connect request.
551 int iw_cm_listen(struct iw_cm_id *cm_id, int backlog)
553 struct iwcm_id_private *cm_id_priv;
557 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
560 backlog = default_backlog;
562 ret = alloc_work_entries(cm_id_priv, backlog);
566 spin_lock_irqsave(&cm_id_priv->lock, flags);
567 switch (cm_id_priv->state) {
568 case IW_CM_STATE_IDLE:
569 cm_id_priv->state = IW_CM_STATE_LISTEN;
570 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
571 ret = iw_cm_map(cm_id, false);
573 ret = cm_id->device->iwcm->create_listen(cm_id, backlog);
575 cm_id_priv->state = IW_CM_STATE_IDLE;
576 spin_lock_irqsave(&cm_id_priv->lock, flags);
581 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
585 EXPORT_SYMBOL(iw_cm_listen);
590 * Rejects an inbound connection request. No events are generated.
592 int iw_cm_reject(struct iw_cm_id *cm_id,
593 const void *private_data,
596 struct iwcm_id_private *cm_id_priv;
600 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
601 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
603 spin_lock_irqsave(&cm_id_priv->lock, flags);
604 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
605 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
606 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
607 wake_up_all(&cm_id_priv->connect_wait);
610 cm_id_priv->state = IW_CM_STATE_IDLE;
611 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
613 ret = cm_id->device->iwcm->reject(cm_id, private_data,
616 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
617 wake_up_all(&cm_id_priv->connect_wait);
621 EXPORT_SYMBOL(iw_cm_reject);
624 * CM_ID <-- ESTABLISHED
626 * Accepts an inbound connection request and generates an ESTABLISHED
627 * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block
628 * until the ESTABLISHED event is received from the provider.
630 int iw_cm_accept(struct iw_cm_id *cm_id,
631 struct iw_cm_conn_param *iw_param)
633 struct iwcm_id_private *cm_id_priv;
638 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
639 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
641 spin_lock_irqsave(&cm_id_priv->lock, flags);
642 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
643 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
644 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
645 wake_up_all(&cm_id_priv->connect_wait);
648 /* Get the ib_qp given the QPN */
649 qp = cm_id->device->iwcm->get_qp(cm_id->device, iw_param->qpn);
651 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
652 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
653 wake_up_all(&cm_id_priv->connect_wait);
656 cm_id->device->iwcm->add_ref(qp);
658 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
660 ret = cm_id->device->iwcm->accept(cm_id, iw_param);
662 /* An error on accept precludes provider events */
663 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
664 cm_id_priv->state = IW_CM_STATE_IDLE;
665 spin_lock_irqsave(&cm_id_priv->lock, flags);
666 if (cm_id_priv->qp) {
667 cm_id->device->iwcm->rem_ref(qp);
668 cm_id_priv->qp = NULL;
670 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
671 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
672 wake_up_all(&cm_id_priv->connect_wait);
677 EXPORT_SYMBOL(iw_cm_accept);
680 * Active Side: CM_ID <-- CONN_SENT
682 * If successful, results in the generation of a CONNECT_REPLY
683 * event. iw_cm_disconnect and iw_cm_destroy will block until the
684 * CONNECT_REPLY event is received from the provider.
686 int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param)
688 struct iwcm_id_private *cm_id_priv;
693 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
695 ret = alloc_work_entries(cm_id_priv, 4);
699 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
700 spin_lock_irqsave(&cm_id_priv->lock, flags);
702 if (cm_id_priv->state != IW_CM_STATE_IDLE) {
707 /* Get the ib_qp given the QPN */
708 qp = cm_id->device->iwcm->get_qp(cm_id->device, iw_param->qpn);
713 cm_id->device->iwcm->add_ref(qp);
715 cm_id_priv->state = IW_CM_STATE_CONN_SENT;
716 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
718 ret = iw_cm_map(cm_id, true);
720 ret = cm_id->device->iwcm->connect(cm_id, iw_param);
722 return 0; /* success */
724 spin_lock_irqsave(&cm_id_priv->lock, flags);
725 if (cm_id_priv->qp) {
726 cm_id->device->iwcm->rem_ref(qp);
727 cm_id_priv->qp = NULL;
729 cm_id_priv->state = IW_CM_STATE_IDLE;
731 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
732 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
733 wake_up_all(&cm_id_priv->connect_wait);
736 EXPORT_SYMBOL(iw_cm_connect);
739 * Passive Side: new CM_ID <-- CONN_RECV
741 * Handles an inbound connect request. The function creates a new
742 * iw_cm_id to represent the new connection and inherits the client
743 * callback function and other attributes from the listening parent.
745 * The work item contains a pointer to the listen_cm_id and the event. The
746 * listen_cm_id contains the client cm_handler, context and
747 * device. These are copied when the device is cloned. The event
748 * contains the new four tuple.
750 * An error on the child should not affect the parent, so this
751 * function does not return a value.
753 static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv,
754 struct iw_cm_event *iw_event)
757 struct iw_cm_id *cm_id;
758 struct iwcm_id_private *cm_id_priv;
762 * The provider should never generate a connection request
763 * event with a bad status.
765 BUG_ON(iw_event->status);
767 cm_id = iw_create_cm_id(listen_id_priv->id.device,
768 listen_id_priv->id.cm_handler,
769 listen_id_priv->id.context);
770 /* If the cm_id could not be created, ignore the request */
774 cm_id->provider_data = iw_event->provider_data;
775 cm_id->m_local_addr = iw_event->local_addr;
776 cm_id->m_remote_addr = iw_event->remote_addr;
777 cm_id->local_addr = listen_id_priv->id.local_addr;
779 ret = iwpm_get_remote_info(&listen_id_priv->id.m_local_addr,
780 &iw_event->remote_addr,
784 cm_id->remote_addr = iw_event->remote_addr;
786 iw_cm_check_wildcard(&listen_id_priv->id.m_local_addr,
787 &iw_event->local_addr,
789 iw_event->local_addr = cm_id->local_addr;
790 iw_event->remote_addr = cm_id->remote_addr;
793 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
794 cm_id_priv->state = IW_CM_STATE_CONN_RECV;
797 * We could be destroying the listening id. If so, ignore this
800 spin_lock_irqsave(&listen_id_priv->lock, flags);
801 if (listen_id_priv->state != IW_CM_STATE_LISTEN) {
802 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
803 iw_cm_reject(cm_id, NULL, 0);
804 iw_destroy_cm_id(cm_id);
807 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
809 ret = alloc_work_entries(cm_id_priv, 3);
811 iw_cm_reject(cm_id, NULL, 0);
812 iw_destroy_cm_id(cm_id);
816 /* Call the client CM handler */
817 ret = cm_id->cm_handler(cm_id, iw_event);
819 iw_cm_reject(cm_id, NULL, 0);
820 iw_destroy_cm_id(cm_id);
824 if (iw_event->private_data_len)
825 kfree(iw_event->private_data);
829 * Passive Side: CM_ID <-- ESTABLISHED
831 * The provider generated an ESTABLISHED event which means that
832 * the MPA negotion has completed successfully and we are now in MPA
835 * This event can only be received in the CONN_RECV state. If the
836 * remote peer closed, the ESTABLISHED event would be received followed
837 * by the CLOSE event. If the app closes, it will block until we wake
838 * it up after processing this event.
840 static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv,
841 struct iw_cm_event *iw_event)
846 spin_lock_irqsave(&cm_id_priv->lock, flags);
849 * We clear the CONNECT_WAIT bit here to allow the callback
850 * function to call iw_cm_disconnect. Calling iw_destroy_cm_id
851 * from a callback handler is not allowed.
853 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
854 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
855 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
856 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
857 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
858 wake_up_all(&cm_id_priv->connect_wait);
864 * Active Side: CM_ID <-- ESTABLISHED
866 * The app has called connect and is waiting for the established event to
867 * post it's requests to the server. This event will wake up anyone
868 * blocked in iw_cm_disconnect or iw_destroy_id.
870 static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv,
871 struct iw_cm_event *iw_event)
876 spin_lock_irqsave(&cm_id_priv->lock, flags);
878 * Clear the connect wait bit so a callback function calling
879 * iw_cm_disconnect will not wait and deadlock this thread
881 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
882 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT);
883 if (iw_event->status == 0) {
884 cm_id_priv->id.m_local_addr = iw_event->local_addr;
885 cm_id_priv->id.m_remote_addr = iw_event->remote_addr;
886 iw_event->local_addr = cm_id_priv->id.local_addr;
887 iw_event->remote_addr = cm_id_priv->id.remote_addr;
888 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
890 /* REJECTED or RESET */
891 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
892 cm_id_priv->qp = NULL;
893 cm_id_priv->state = IW_CM_STATE_IDLE;
895 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
896 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
898 if (iw_event->private_data_len)
899 kfree(iw_event->private_data);
901 /* Wake up waiters on connect complete */
902 wake_up_all(&cm_id_priv->connect_wait);
910 * If in the ESTABLISHED state, move to CLOSING.
912 static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv,
913 struct iw_cm_event *iw_event)
917 spin_lock_irqsave(&cm_id_priv->lock, flags);
918 if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED)
919 cm_id_priv->state = IW_CM_STATE_CLOSING;
920 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
926 * If in the ESTBLISHED or CLOSING states, the QP will have have been
927 * moved by the provider to the ERR state. Disassociate the CM_ID from
928 * the QP, move to IDLE, and remove the 'connected' reference.
930 * If in some other state, the cm_id was destroyed asynchronously.
931 * This is the last reference that will result in waking up
932 * the app thread blocked in iw_destroy_cm_id.
934 static int cm_close_handler(struct iwcm_id_private *cm_id_priv,
935 struct iw_cm_event *iw_event)
939 spin_lock_irqsave(&cm_id_priv->lock, flags);
941 if (cm_id_priv->qp) {
942 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
943 cm_id_priv->qp = NULL;
945 switch (cm_id_priv->state) {
946 case IW_CM_STATE_ESTABLISHED:
947 case IW_CM_STATE_CLOSING:
948 cm_id_priv->state = IW_CM_STATE_IDLE;
949 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
950 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
951 spin_lock_irqsave(&cm_id_priv->lock, flags);
953 case IW_CM_STATE_DESTROYING:
958 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
963 static int process_event(struct iwcm_id_private *cm_id_priv,
964 struct iw_cm_event *iw_event)
968 switch (iw_event->event) {
969 case IW_CM_EVENT_CONNECT_REQUEST:
970 cm_conn_req_handler(cm_id_priv, iw_event);
972 case IW_CM_EVENT_CONNECT_REPLY:
973 ret = cm_conn_rep_handler(cm_id_priv, iw_event);
975 case IW_CM_EVENT_ESTABLISHED:
976 ret = cm_conn_est_handler(cm_id_priv, iw_event);
978 case IW_CM_EVENT_DISCONNECT:
979 cm_disconnect_handler(cm_id_priv, iw_event);
981 case IW_CM_EVENT_CLOSE:
982 ret = cm_close_handler(cm_id_priv, iw_event);
992 * Process events on the work_list for the cm_id. If the callback
993 * function requests that the cm_id be deleted, a flag is set in the
994 * cm_id flags to indicate that when the last reference is
995 * removed, the cm_id is to be destroyed. This is necessary to
996 * distinguish between an object that will be destroyed by the app
997 * thread asleep on the destroy_comp list vs. an object destroyed
998 * here synchronously when the last reference is removed.
1000 static void cm_work_handler(struct work_struct *_work)
1002 struct iwcm_work *work = container_of(_work, struct iwcm_work, work);
1003 struct iw_cm_event levent;
1004 struct iwcm_id_private *cm_id_priv = work->cm_id;
1005 unsigned long flags;
1009 spin_lock_irqsave(&cm_id_priv->lock, flags);
1010 empty = list_empty(&cm_id_priv->work_list);
1012 work = list_entry(cm_id_priv->work_list.next,
1013 struct iwcm_work, list);
1014 list_del_init(&work->list);
1015 empty = list_empty(&cm_id_priv->work_list);
1016 levent = work->event;
1018 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1020 if (!test_bit(IWCM_F_DROP_EVENTS, &cm_id_priv->flags)) {
1021 ret = process_event(cm_id_priv, &levent);
1023 destroy_cm_id(&cm_id_priv->id);
1025 pr_debug("dropping event %d\n", levent.event);
1026 if (iwcm_deref_id(cm_id_priv))
1030 spin_lock_irqsave(&cm_id_priv->lock, flags);
1032 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1036 * This function is called on interrupt context. Schedule events on
1037 * the iwcm_wq thread to allow callback functions to downcall into
1038 * the CM and/or block. Events are queued to a per-CM_ID
1039 * work_list. If this is the first event on the work_list, the work
1040 * element is also queued on the iwcm_wq thread.
1042 * Each event holds a reference on the cm_id. Until the last posted
1043 * event has been delivered and processed, the cm_id cannot be
1047 * 0 - the event was handled.
1048 * -ENOMEM - the event was not handled due to lack of resources.
1050 static int cm_event_handler(struct iw_cm_id *cm_id,
1051 struct iw_cm_event *iw_event)
1053 struct iwcm_work *work;
1054 struct iwcm_id_private *cm_id_priv;
1055 unsigned long flags;
1058 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
1060 spin_lock_irqsave(&cm_id_priv->lock, flags);
1061 work = get_work(cm_id_priv);
1067 INIT_WORK(&work->work, cm_work_handler);
1068 work->cm_id = cm_id_priv;
1069 work->event = *iw_event;
1071 if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST ||
1072 work->event.event == IW_CM_EVENT_CONNECT_REPLY) &&
1073 work->event.private_data_len) {
1074 ret = copy_private_data(&work->event);
1081 atomic_inc(&cm_id_priv->refcount);
1082 if (list_empty(&cm_id_priv->work_list)) {
1083 list_add_tail(&work->list, &cm_id_priv->work_list);
1084 queue_work(iwcm_wq, &work->work);
1086 list_add_tail(&work->list, &cm_id_priv->work_list);
1088 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1092 static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv,
1093 struct ib_qp_attr *qp_attr,
1096 unsigned long flags;
1099 spin_lock_irqsave(&cm_id_priv->lock, flags);
1100 switch (cm_id_priv->state) {
1101 case IW_CM_STATE_IDLE:
1102 case IW_CM_STATE_CONN_SENT:
1103 case IW_CM_STATE_CONN_RECV:
1104 case IW_CM_STATE_ESTABLISHED:
1105 *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS;
1106 qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE|
1107 IB_ACCESS_REMOTE_READ;
1114 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1118 static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv,
1119 struct ib_qp_attr *qp_attr,
1122 unsigned long flags;
1125 spin_lock_irqsave(&cm_id_priv->lock, flags);
1126 switch (cm_id_priv->state) {
1127 case IW_CM_STATE_IDLE:
1128 case IW_CM_STATE_CONN_SENT:
1129 case IW_CM_STATE_CONN_RECV:
1130 case IW_CM_STATE_ESTABLISHED:
1138 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
1142 int iw_cm_init_qp_attr(struct iw_cm_id *cm_id,
1143 struct ib_qp_attr *qp_attr,
1146 struct iwcm_id_private *cm_id_priv;
1149 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
1150 switch (qp_attr->qp_state) {
1153 ret = iwcm_init_qp_init_attr(cm_id_priv,
1154 qp_attr, qp_attr_mask);
1157 ret = iwcm_init_qp_rts_attr(cm_id_priv,
1158 qp_attr, qp_attr_mask);
1166 EXPORT_SYMBOL(iw_cm_init_qp_attr);
1168 static int __init iw_cm_init(void)
1172 ret = iwpm_init(RDMA_NL_IWCM);
1174 pr_err("iw_cm: couldn't init iwpm\n");
1176 rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table);
1177 iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", 0);
1181 iwcm_ctl_table_hdr = register_net_sysctl(&init_net, "net/iw_cm",
1183 if (!iwcm_ctl_table_hdr) {
1184 pr_err("iw_cm: couldn't register sysctl paths\n");
1185 destroy_workqueue(iwcm_wq);
1192 static void __exit iw_cm_cleanup(void)
1194 unregister_net_sysctl_table(iwcm_ctl_table_hdr);
1195 destroy_workqueue(iwcm_wq);
1196 rdma_nl_unregister(RDMA_NL_IWCM);
1197 iwpm_exit(RDMA_NL_IWCM);
1200 MODULE_ALIAS_RDMA_NETLINK(RDMA_NL_IWCM, 2);
1202 module_init(iw_cm_init);
1203 module_exit(iw_cm_cleanup);