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authorTom Tucker <tom@opengridcomputing.com>2006-08-03 17:02:40 -0400
committerRoland Dreier <rolandd@cisco.com>2006-09-22 18:22:46 -0400
commit922a8e9fb2e0711212badce47a41137e2ca04cb3 (patch)
tree54af57ac9f2ddcaf0e6fdead4d9175eecd9e06e2 /drivers
parent3cd965646b7cb75ae84dd0daf6258adf20e4f169 (diff)
RDMA: iWARP Connection Manager.
Add an iWARP Connection Manager (CM), which abstracts connection management for iWARP devices (RNICs). It is a logical instance of the xx_cm where xx is the transport type (ib or iw). The symbols exported are used by the transport independent rdma_cm module, and are available also for transport dependent ULPs. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/infiniband/core/iwcm.c1019
-rw-r--r--drivers/infiniband/core/iwcm.h62
2 files changed, 1081 insertions, 0 deletions
diff --git a/drivers/infiniband/core/iwcm.c b/drivers/infiniband/core/iwcm.c
new file mode 100644
index 000000000000..c3fb304a4e86
--- /dev/null
+++ b/drivers/infiniband/core/iwcm.c
@@ -0,0 +1,1019 @@
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/pci.h>
43#include <linux/rbtree.h>
44#include <linux/spinlock.h>
45#include <linux/workqueue.h>
46#include <linux/completion.h>
47
48#include <rdma/iw_cm.h>
49#include <rdma/ib_addr.h>
50
51#include "iwcm.h"
52
53MODULE_AUTHOR("Tom Tucker");
54MODULE_DESCRIPTION("iWARP CM");
55MODULE_LICENSE("Dual BSD/GPL");
56
57static struct workqueue_struct *iwcm_wq;
58struct iwcm_work {
59 struct work_struct work;
60 struct iwcm_id_private *cm_id;
61 struct list_head list;
62 struct iw_cm_event event;
63 struct list_head free_list;
64};
65
66/*
67 * The following services provide a mechanism for pre-allocating iwcm_work
68 * elements. The design pre-allocates them based on the cm_id type:
69 * LISTENING IDS: Get enough elements preallocated to handle the
70 * listen backlog.
71 * ACTIVE IDS: 4: CONNECT_REPLY, ESTABLISHED, DISCONNECT, CLOSE
72 * PASSIVE IDS: 3: ESTABLISHED, DISCONNECT, CLOSE
73 *
74 * Allocating them in connect and listen avoids having to deal
75 * with allocation failures on the event upcall from the provider (which
76 * is called in the interrupt context).
77 *
78 * One exception is when creating the cm_id for incoming connection requests.
79 * There are two cases:
80 * 1) in the event upcall, cm_event_handler(), for a listening cm_id. If
81 * the backlog is exceeded, then no more connection request events will
82 * be processed. cm_event_handler() returns -ENOMEM in this case. Its up
83 * to the provider to reject the connectino request.
84 * 2) in the connection request workqueue handler, cm_conn_req_handler().
85 * If work elements cannot be allocated for the new connect request cm_id,
86 * then IWCM will call the provider reject method. This is ok since
87 * cm_conn_req_handler() runs in the workqueue thread context.
88 */
89
90static struct iwcm_work *get_work(struct iwcm_id_private *cm_id_priv)
91{
92 struct iwcm_work *work;
93
94 if (list_empty(&cm_id_priv->work_free_list))
95 return NULL;
96 work = list_entry(cm_id_priv->work_free_list.next, struct iwcm_work,
97 free_list);
98 list_del_init(&work->free_list);
99 return work;
100}
101
102static void put_work(struct iwcm_work *work)
103{
104 list_add(&work->free_list, &work->cm_id->work_free_list);
105}
106
107static void dealloc_work_entries(struct iwcm_id_private *cm_id_priv)
108{
109 struct list_head *e, *tmp;
110
111 list_for_each_safe(e, tmp, &cm_id_priv->work_free_list)
112 kfree(list_entry(e, struct iwcm_work, free_list));
113}
114
115static int alloc_work_entries(struct iwcm_id_private *cm_id_priv, int count)
116{
117 struct iwcm_work *work;
118
119 BUG_ON(!list_empty(&cm_id_priv->work_free_list));
120 while (count--) {
121 work = kmalloc(sizeof(struct iwcm_work), GFP_KERNEL);
122 if (!work) {
123 dealloc_work_entries(cm_id_priv);
124 return -ENOMEM;
125 }
126 work->cm_id = cm_id_priv;
127 INIT_LIST_HEAD(&work->list);
128 put_work(work);
129 }
130 return 0;
131}
132
133/*
134 * Save private data from incoming connection requests in the
135 * cm_id_priv so the low level driver doesn't have to. Adjust
136 * the event ptr to point to the local copy.
137 */
138static int copy_private_data(struct iwcm_id_private *cm_id_priv,
139 struct iw_cm_event *event)
140{
141 void *p;
142
143 p = kmalloc(event->private_data_len, GFP_ATOMIC);
144 if (!p)
145 return -ENOMEM;
146 memcpy(p, event->private_data, event->private_data_len);
147 event->private_data = p;
148 return 0;
149}
150
151/*
152 * Release a reference on cm_id. If the last reference is being removed
153 * and iw_destroy_cm_id is waiting, wake up the waiting thread.
154 */
155static int iwcm_deref_id(struct iwcm_id_private *cm_id_priv)
156{
157 int ret = 0;
158
159 BUG_ON(atomic_read(&cm_id_priv->refcount)==0);
160 if (atomic_dec_and_test(&cm_id_priv->refcount)) {
161 BUG_ON(!list_empty(&cm_id_priv->work_list));
162 if (waitqueue_active(&cm_id_priv->destroy_comp.wait)) {
163 BUG_ON(cm_id_priv->state != IW_CM_STATE_DESTROYING);
164 BUG_ON(test_bit(IWCM_F_CALLBACK_DESTROY,
165 &cm_id_priv->flags));
166 ret = 1;
167 }
168 complete(&cm_id_priv->destroy_comp);
169 }
170
171 return ret;
172}
173
174static void add_ref(struct iw_cm_id *cm_id)
175{
176 struct iwcm_id_private *cm_id_priv;
177 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
178 atomic_inc(&cm_id_priv->refcount);
179}
180
181static void rem_ref(struct iw_cm_id *cm_id)
182{
183 struct iwcm_id_private *cm_id_priv;
184 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
185 iwcm_deref_id(cm_id_priv);
186}
187
188static int cm_event_handler(struct iw_cm_id *cm_id, struct iw_cm_event *event);
189
190struct iw_cm_id *iw_create_cm_id(struct ib_device *device,
191 iw_cm_handler cm_handler,
192 void *context)
193{
194 struct iwcm_id_private *cm_id_priv;
195
196 cm_id_priv = kzalloc(sizeof(*cm_id_priv), GFP_KERNEL);
197 if (!cm_id_priv)
198 return ERR_PTR(-ENOMEM);
199
200 cm_id_priv->state = IW_CM_STATE_IDLE;
201 cm_id_priv->id.device = device;
202 cm_id_priv->id.cm_handler = cm_handler;
203 cm_id_priv->id.context = context;
204 cm_id_priv->id.event_handler = cm_event_handler;
205 cm_id_priv->id.add_ref = add_ref;
206 cm_id_priv->id.rem_ref = rem_ref;
207 spin_lock_init(&cm_id_priv->lock);
208 atomic_set(&cm_id_priv->refcount, 1);
209 init_waitqueue_head(&cm_id_priv->connect_wait);
210 init_completion(&cm_id_priv->destroy_comp);
211 INIT_LIST_HEAD(&cm_id_priv->work_list);
212 INIT_LIST_HEAD(&cm_id_priv->work_free_list);
213
214 return &cm_id_priv->id;
215}
216EXPORT_SYMBOL(iw_create_cm_id);
217
218
219static int iwcm_modify_qp_err(struct ib_qp *qp)
220{
221 struct ib_qp_attr qp_attr;
222
223 if (!qp)
224 return -EINVAL;
225
226 qp_attr.qp_state = IB_QPS_ERR;
227 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
228}
229
230/*
231 * This is really the RDMAC CLOSING state. It is most similar to the
232 * IB SQD QP state.
233 */
234static int iwcm_modify_qp_sqd(struct ib_qp *qp)
235{
236 struct ib_qp_attr qp_attr;
237
238 BUG_ON(qp == NULL);
239 qp_attr.qp_state = IB_QPS_SQD;
240 return ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
241}
242
243/*
244 * CM_ID <-- CLOSING
245 *
246 * Block if a passive or active connection is currenlty being processed. Then
247 * process the event as follows:
248 * - If we are ESTABLISHED, move to CLOSING and modify the QP state
249 * based on the abrupt flag
250 * - If the connection is already in the CLOSING or IDLE state, the peer is
251 * disconnecting concurrently with us and we've already seen the
252 * DISCONNECT event -- ignore the request and return 0
253 * - Disconnect on a listening endpoint returns -EINVAL
254 */
255int iw_cm_disconnect(struct iw_cm_id *cm_id, int abrupt)
256{
257 struct iwcm_id_private *cm_id_priv;
258 unsigned long flags;
259 int ret = 0;
260 struct ib_qp *qp = NULL;
261
262 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
263 /* Wait if we're currently in a connect or accept downcall */
264 wait_event(cm_id_priv->connect_wait,
265 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
266
267 spin_lock_irqsave(&cm_id_priv->lock, flags);
268 switch (cm_id_priv->state) {
269 case IW_CM_STATE_ESTABLISHED:
270 cm_id_priv->state = IW_CM_STATE_CLOSING;
271
272 /* QP could be <nul> for user-mode client */
273 if (cm_id_priv->qp)
274 qp = cm_id_priv->qp;
275 else
276 ret = -EINVAL;
277 break;
278 case IW_CM_STATE_LISTEN:
279 ret = -EINVAL;
280 break;
281 case IW_CM_STATE_CLOSING:
282 /* remote peer closed first */
283 case IW_CM_STATE_IDLE:
284 /* accept or connect returned !0 */
285 break;
286 case IW_CM_STATE_CONN_RECV:
287 /*
288 * App called disconnect before/without calling accept after
289 * connect_request event delivered.
290 */
291 break;
292 case IW_CM_STATE_CONN_SENT:
293 /* Can only get here if wait above fails */
294 default:
295 BUG();
296 }
297 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
298
299 if (qp) {
300 if (abrupt)
301 ret = iwcm_modify_qp_err(qp);
302 else
303 ret = iwcm_modify_qp_sqd(qp);
304
305 /*
306 * If both sides are disconnecting the QP could
307 * already be in ERR or SQD states
308 */
309 ret = 0;
310 }
311
312 return ret;
313}
314EXPORT_SYMBOL(iw_cm_disconnect);
315
316/*
317 * CM_ID <-- DESTROYING
318 *
319 * Clean up all resources associated with the connection and release
320 * the initial reference taken by iw_create_cm_id.
321 */
322static void destroy_cm_id(struct iw_cm_id *cm_id)
323{
324 struct iwcm_id_private *cm_id_priv;
325 unsigned long flags;
326 int ret;
327
328 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
329 /*
330 * Wait if we're currently in a connect or accept downcall. A
331 * listening endpoint should never block here.
332 */
333 wait_event(cm_id_priv->connect_wait,
334 !test_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags));
335
336 spin_lock_irqsave(&cm_id_priv->lock, flags);
337 switch (cm_id_priv->state) {
338 case IW_CM_STATE_LISTEN:
339 cm_id_priv->state = IW_CM_STATE_DESTROYING;
340 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
341 /* destroy the listening endpoint */
342 ret = cm_id->device->iwcm->destroy_listen(cm_id);
343 spin_lock_irqsave(&cm_id_priv->lock, flags);
344 break;
345 case IW_CM_STATE_ESTABLISHED:
346 cm_id_priv->state = IW_CM_STATE_DESTROYING;
347 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
348 /* Abrupt close of the connection */
349 (void)iwcm_modify_qp_err(cm_id_priv->qp);
350 spin_lock_irqsave(&cm_id_priv->lock, flags);
351 break;
352 case IW_CM_STATE_IDLE:
353 case IW_CM_STATE_CLOSING:
354 cm_id_priv->state = IW_CM_STATE_DESTROYING;
355 break;
356 case IW_CM_STATE_CONN_RECV:
357 /*
358 * App called destroy before/without calling accept after
359 * receiving connection request event notification.
360 */
361 cm_id_priv->state = IW_CM_STATE_DESTROYING;
362 break;
363 case IW_CM_STATE_CONN_SENT:
364 case IW_CM_STATE_DESTROYING:
365 default:
366 BUG();
367 break;
368 }
369 if (cm_id_priv->qp) {
370 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
371 cm_id_priv->qp = NULL;
372 }
373 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
374
375 (void)iwcm_deref_id(cm_id_priv);
376}
377
378/*
379 * This function is only called by the application thread and cannot
380 * be called by the event thread. The function will wait for all
381 * references to be released on the cm_id and then kfree the cm_id
382 * object.
383 */
384void iw_destroy_cm_id(struct iw_cm_id *cm_id)
385{
386 struct iwcm_id_private *cm_id_priv;
387
388 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
389 BUG_ON(test_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags));
390
391 destroy_cm_id(cm_id);
392
393 wait_for_completion(&cm_id_priv->destroy_comp);
394
395 dealloc_work_entries(cm_id_priv);
396
397 kfree(cm_id_priv);
398}
399EXPORT_SYMBOL(iw_destroy_cm_id);
400
401/*
402 * CM_ID <-- LISTEN
403 *
404 * Start listening for connect requests. Generates one CONNECT_REQUEST
405 * event for each inbound connect request.
406 */
407int iw_cm_listen(struct iw_cm_id *cm_id, int backlog)
408{
409 struct iwcm_id_private *cm_id_priv;
410 unsigned long flags;
411 int ret = 0;
412
413 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
414
415 ret = alloc_work_entries(cm_id_priv, backlog);
416 if (ret)
417 return ret;
418
419 spin_lock_irqsave(&cm_id_priv->lock, flags);
420 switch (cm_id_priv->state) {
421 case IW_CM_STATE_IDLE:
422 cm_id_priv->state = IW_CM_STATE_LISTEN;
423 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
424 ret = cm_id->device->iwcm->create_listen(cm_id, backlog);
425 if (ret)
426 cm_id_priv->state = IW_CM_STATE_IDLE;
427 spin_lock_irqsave(&cm_id_priv->lock, flags);
428 break;
429 default:
430 ret = -EINVAL;
431 }
432 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
433
434 return ret;
435}
436EXPORT_SYMBOL(iw_cm_listen);
437
438/*
439 * CM_ID <-- IDLE
440 *
441 * Rejects an inbound connection request. No events are generated.
442 */
443int iw_cm_reject(struct iw_cm_id *cm_id,
444 const void *private_data,
445 u8 private_data_len)
446{
447 struct iwcm_id_private *cm_id_priv;
448 unsigned long flags;
449 int ret;
450
451 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
452 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
453
454 spin_lock_irqsave(&cm_id_priv->lock, flags);
455 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
456 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
457 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
458 wake_up_all(&cm_id_priv->connect_wait);
459 return -EINVAL;
460 }
461 cm_id_priv->state = IW_CM_STATE_IDLE;
462 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
463
464 ret = cm_id->device->iwcm->reject(cm_id, private_data,
465 private_data_len);
466
467 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
468 wake_up_all(&cm_id_priv->connect_wait);
469
470 return ret;
471}
472EXPORT_SYMBOL(iw_cm_reject);
473
474/*
475 * CM_ID <-- ESTABLISHED
476 *
477 * Accepts an inbound connection request and generates an ESTABLISHED
478 * event. Callers of iw_cm_disconnect and iw_destroy_cm_id will block
479 * until the ESTABLISHED event is received from the provider.
480 */
481int iw_cm_accept(struct iw_cm_id *cm_id,
482 struct iw_cm_conn_param *iw_param)
483{
484 struct iwcm_id_private *cm_id_priv;
485 struct ib_qp *qp;
486 unsigned long flags;
487 int ret;
488
489 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
490 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
491
492 spin_lock_irqsave(&cm_id_priv->lock, flags);
493 if (cm_id_priv->state != IW_CM_STATE_CONN_RECV) {
494 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
495 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
496 wake_up_all(&cm_id_priv->connect_wait);
497 return -EINVAL;
498 }
499 /* Get the ib_qp given the QPN */
500 qp = cm_id->device->iwcm->get_qp(cm_id->device, iw_param->qpn);
501 if (!qp) {
502 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
503 return -EINVAL;
504 }
505 cm_id->device->iwcm->add_ref(qp);
506 cm_id_priv->qp = qp;
507 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
508
509 ret = cm_id->device->iwcm->accept(cm_id, iw_param);
510 if (ret) {
511 /* An error on accept precludes provider events */
512 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
513 cm_id_priv->state = IW_CM_STATE_IDLE;
514 spin_lock_irqsave(&cm_id_priv->lock, flags);
515 if (cm_id_priv->qp) {
516 cm_id->device->iwcm->rem_ref(qp);
517 cm_id_priv->qp = NULL;
518 }
519 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
520 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
521 wake_up_all(&cm_id_priv->connect_wait);
522 }
523
524 return ret;
525}
526EXPORT_SYMBOL(iw_cm_accept);
527
528/*
529 * Active Side: CM_ID <-- CONN_SENT
530 *
531 * If successful, results in the generation of a CONNECT_REPLY
532 * event. iw_cm_disconnect and iw_cm_destroy will block until the
533 * CONNECT_REPLY event is received from the provider.
534 */
535int iw_cm_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *iw_param)
536{
537 struct iwcm_id_private *cm_id_priv;
538 int ret = 0;
539 unsigned long flags;
540 struct ib_qp *qp;
541
542 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
543
544 ret = alloc_work_entries(cm_id_priv, 4);
545 if (ret)
546 return ret;
547
548 set_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
549 spin_lock_irqsave(&cm_id_priv->lock, flags);
550
551 if (cm_id_priv->state != IW_CM_STATE_IDLE) {
552 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
553 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
554 wake_up_all(&cm_id_priv->connect_wait);
555 return -EINVAL;
556 }
557
558 /* Get the ib_qp given the QPN */
559 qp = cm_id->device->iwcm->get_qp(cm_id->device, iw_param->qpn);
560 if (!qp) {
561 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
562 return -EINVAL;
563 }
564 cm_id->device->iwcm->add_ref(qp);
565 cm_id_priv->qp = qp;
566 cm_id_priv->state = IW_CM_STATE_CONN_SENT;
567 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
568
569 ret = cm_id->device->iwcm->connect(cm_id, iw_param);
570 if (ret) {
571 spin_lock_irqsave(&cm_id_priv->lock, flags);
572 if (cm_id_priv->qp) {
573 cm_id->device->iwcm->rem_ref(qp);
574 cm_id_priv->qp = NULL;
575 }
576 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
577 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT);
578 cm_id_priv->state = IW_CM_STATE_IDLE;
579 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
580 wake_up_all(&cm_id_priv->connect_wait);
581 }
582
583 return ret;
584}
585EXPORT_SYMBOL(iw_cm_connect);
586
587/*
588 * Passive Side: new CM_ID <-- CONN_RECV
589 *
590 * Handles an inbound connect request. The function creates a new
591 * iw_cm_id to represent the new connection and inherits the client
592 * callback function and other attributes from the listening parent.
593 *
594 * The work item contains a pointer to the listen_cm_id and the event. The
595 * listen_cm_id contains the client cm_handler, context and
596 * device. These are copied when the device is cloned. The event
597 * contains the new four tuple.
598 *
599 * An error on the child should not affect the parent, so this
600 * function does not return a value.
601 */
602static void cm_conn_req_handler(struct iwcm_id_private *listen_id_priv,
603 struct iw_cm_event *iw_event)
604{
605 unsigned long flags;
606 struct iw_cm_id *cm_id;
607 struct iwcm_id_private *cm_id_priv;
608 int ret;
609
610 /*
611 * The provider should never generate a connection request
612 * event with a bad status.
613 */
614 BUG_ON(iw_event->status);
615
616 /*
617 * We could be destroying the listening id. If so, ignore this
618 * upcall.
619 */
620 spin_lock_irqsave(&listen_id_priv->lock, flags);
621 if (listen_id_priv->state != IW_CM_STATE_LISTEN) {
622 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
623 return;
624 }
625 spin_unlock_irqrestore(&listen_id_priv->lock, flags);
626
627 cm_id = iw_create_cm_id(listen_id_priv->id.device,
628 listen_id_priv->id.cm_handler,
629 listen_id_priv->id.context);
630 /* If the cm_id could not be created, ignore the request */
631 if (IS_ERR(cm_id))
632 return;
633
634 cm_id->provider_data = iw_event->provider_data;
635 cm_id->local_addr = iw_event->local_addr;
636 cm_id->remote_addr = iw_event->remote_addr;
637
638 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
639 cm_id_priv->state = IW_CM_STATE_CONN_RECV;
640
641 ret = alloc_work_entries(cm_id_priv, 3);
642 if (ret) {
643 iw_cm_reject(cm_id, NULL, 0);
644 iw_destroy_cm_id(cm_id);
645 return;
646 }
647
648 /* Call the client CM handler */
649 ret = cm_id->cm_handler(cm_id, iw_event);
650 if (ret) {
651 set_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags);
652 destroy_cm_id(cm_id);
653 if (atomic_read(&cm_id_priv->refcount)==0)
654 kfree(cm_id);
655 }
656
657 if (iw_event->private_data_len)
658 kfree(iw_event->private_data);
659}
660
661/*
662 * Passive Side: CM_ID <-- ESTABLISHED
663 *
664 * The provider generated an ESTABLISHED event which means that
665 * the MPA negotion has completed successfully and we are now in MPA
666 * FPDU mode.
667 *
668 * This event can only be received in the CONN_RECV state. If the
669 * remote peer closed, the ESTABLISHED event would be received followed
670 * by the CLOSE event. If the app closes, it will block until we wake
671 * it up after processing this event.
672 */
673static int cm_conn_est_handler(struct iwcm_id_private *cm_id_priv,
674 struct iw_cm_event *iw_event)
675{
676 unsigned long flags;
677 int ret = 0;
678
679 spin_lock_irqsave(&cm_id_priv->lock, flags);
680
681 /*
682 * We clear the CONNECT_WAIT bit here to allow the callback
683 * function to call iw_cm_disconnect. Calling iw_destroy_cm_id
684 * from a callback handler is not allowed.
685 */
686 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
687 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_RECV);
688 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
689 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
690 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
691 wake_up_all(&cm_id_priv->connect_wait);
692
693 return ret;
694}
695
696/*
697 * Active Side: CM_ID <-- ESTABLISHED
698 *
699 * The app has called connect and is waiting for the established event to
700 * post it's requests to the server. This event will wake up anyone
701 * blocked in iw_cm_disconnect or iw_destroy_id.
702 */
703static int cm_conn_rep_handler(struct iwcm_id_private *cm_id_priv,
704 struct iw_cm_event *iw_event)
705{
706 unsigned long flags;
707 int ret = 0;
708
709 spin_lock_irqsave(&cm_id_priv->lock, flags);
710 /*
711 * Clear the connect wait bit so a callback function calling
712 * iw_cm_disconnect will not wait and deadlock this thread
713 */
714 clear_bit(IWCM_F_CONNECT_WAIT, &cm_id_priv->flags);
715 BUG_ON(cm_id_priv->state != IW_CM_STATE_CONN_SENT);
716 if (iw_event->status == IW_CM_EVENT_STATUS_ACCEPTED) {
717 cm_id_priv->id.local_addr = iw_event->local_addr;
718 cm_id_priv->id.remote_addr = iw_event->remote_addr;
719 cm_id_priv->state = IW_CM_STATE_ESTABLISHED;
720 } else {
721 /* REJECTED or RESET */
722 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
723 cm_id_priv->qp = NULL;
724 cm_id_priv->state = IW_CM_STATE_IDLE;
725 }
726 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
727 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
728
729 if (iw_event->private_data_len)
730 kfree(iw_event->private_data);
731
732 /* Wake up waiters on connect complete */
733 wake_up_all(&cm_id_priv->connect_wait);
734
735 return ret;
736}
737
738/*
739 * CM_ID <-- CLOSING
740 *
741 * If in the ESTABLISHED state, move to CLOSING.
742 */
743static void cm_disconnect_handler(struct iwcm_id_private *cm_id_priv,
744 struct iw_cm_event *iw_event)
745{
746 unsigned long flags;
747
748 spin_lock_irqsave(&cm_id_priv->lock, flags);
749 if (cm_id_priv->state == IW_CM_STATE_ESTABLISHED)
750 cm_id_priv->state = IW_CM_STATE_CLOSING;
751 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
752}
753
754/*
755 * CM_ID <-- IDLE
756 *
757 * If in the ESTBLISHED or CLOSING states, the QP will have have been
758 * moved by the provider to the ERR state. Disassociate the CM_ID from
759 * the QP, move to IDLE, and remove the 'connected' reference.
760 *
761 * If in some other state, the cm_id was destroyed asynchronously.
762 * This is the last reference that will result in waking up
763 * the app thread blocked in iw_destroy_cm_id.
764 */
765static int cm_close_handler(struct iwcm_id_private *cm_id_priv,
766 struct iw_cm_event *iw_event)
767{
768 unsigned long flags;
769 int ret = 0;
770 spin_lock_irqsave(&cm_id_priv->lock, flags);
771
772 if (cm_id_priv->qp) {
773 cm_id_priv->id.device->iwcm->rem_ref(cm_id_priv->qp);
774 cm_id_priv->qp = NULL;
775 }
776 switch (cm_id_priv->state) {
777 case IW_CM_STATE_ESTABLISHED:
778 case IW_CM_STATE_CLOSING:
779 cm_id_priv->state = IW_CM_STATE_IDLE;
780 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
781 ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, iw_event);
782 spin_lock_irqsave(&cm_id_priv->lock, flags);
783 break;
784 case IW_CM_STATE_DESTROYING:
785 break;
786 default:
787 BUG();
788 }
789 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
790
791 return ret;
792}
793
794static int process_event(struct iwcm_id_private *cm_id_priv,
795 struct iw_cm_event *iw_event)
796{
797 int ret = 0;
798
799 switch (iw_event->event) {
800 case IW_CM_EVENT_CONNECT_REQUEST:
801 cm_conn_req_handler(cm_id_priv, iw_event);
802 break;
803 case IW_CM_EVENT_CONNECT_REPLY:
804 ret = cm_conn_rep_handler(cm_id_priv, iw_event);
805 break;
806 case IW_CM_EVENT_ESTABLISHED:
807 ret = cm_conn_est_handler(cm_id_priv, iw_event);
808 break;
809 case IW_CM_EVENT_DISCONNECT:
810 cm_disconnect_handler(cm_id_priv, iw_event);
811 break;
812 case IW_CM_EVENT_CLOSE:
813 ret = cm_close_handler(cm_id_priv, iw_event);
814 break;
815 default:
816 BUG();
817 }
818
819 return ret;
820}
821
822/*
823 * Process events on the work_list for the cm_id. If the callback
824 * function requests that the cm_id be deleted, a flag is set in the
825 * cm_id flags to indicate that when the last reference is
826 * removed, the cm_id is to be destroyed. This is necessary to
827 * distinguish between an object that will be destroyed by the app
828 * thread asleep on the destroy_comp list vs. an object destroyed
829 * here synchronously when the last reference is removed.
830 */
831static void cm_work_handler(void *arg)
832{
833 struct iwcm_work *work = arg, lwork;
834 struct iwcm_id_private *cm_id_priv = work->cm_id;
835 unsigned long flags;
836 int empty;
837 int ret = 0;
838
839 spin_lock_irqsave(&cm_id_priv->lock, flags);
840 empty = list_empty(&cm_id_priv->work_list);
841 while (!empty) {
842 work = list_entry(cm_id_priv->work_list.next,
843 struct iwcm_work, list);
844 list_del_init(&work->list);
845 empty = list_empty(&cm_id_priv->work_list);
846 lwork = *work;
847 put_work(work);
848 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
849
850 ret = process_event(cm_id_priv, &work->event);
851 if (ret) {
852 set_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags);
853 destroy_cm_id(&cm_id_priv->id);
854 }
855 BUG_ON(atomic_read(&cm_id_priv->refcount)==0);
856 if (iwcm_deref_id(cm_id_priv))
857 return;
858
859 if (atomic_read(&cm_id_priv->refcount)==0 &&
860 test_bit(IWCM_F_CALLBACK_DESTROY, &cm_id_priv->flags)) {
861 dealloc_work_entries(cm_id_priv);
862 kfree(cm_id_priv);
863 return;
864 }
865 spin_lock_irqsave(&cm_id_priv->lock, flags);
866 }
867 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
868}
869
870/*
871 * This function is called on interrupt context. Schedule events on
872 * the iwcm_wq thread to allow callback functions to downcall into
873 * the CM and/or block. Events are queued to a per-CM_ID
874 * work_list. If this is the first event on the work_list, the work
875 * element is also queued on the iwcm_wq thread.
876 *
877 * Each event holds a reference on the cm_id. Until the last posted
878 * event has been delivered and processed, the cm_id cannot be
879 * deleted.
880 *
881 * Returns:
882 * 0 - the event was handled.
883 * -ENOMEM - the event was not handled due to lack of resources.
884 */
885static int cm_event_handler(struct iw_cm_id *cm_id,
886 struct iw_cm_event *iw_event)
887{
888 struct iwcm_work *work;
889 struct iwcm_id_private *cm_id_priv;
890 unsigned long flags;
891 int ret = 0;
892
893 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
894
895 spin_lock_irqsave(&cm_id_priv->lock, flags);
896 work = get_work(cm_id_priv);
897 if (!work) {
898 ret = -ENOMEM;
899 goto out;
900 }
901
902 INIT_WORK(&work->work, cm_work_handler, work);
903 work->cm_id = cm_id_priv;
904 work->event = *iw_event;
905
906 if ((work->event.event == IW_CM_EVENT_CONNECT_REQUEST ||
907 work->event.event == IW_CM_EVENT_CONNECT_REPLY) &&
908 work->event.private_data_len) {
909 ret = copy_private_data(cm_id_priv, &work->event);
910 if (ret) {
911 put_work(work);
912 goto out;
913 }
914 }
915
916 atomic_inc(&cm_id_priv->refcount);
917 if (list_empty(&cm_id_priv->work_list)) {
918 list_add_tail(&work->list, &cm_id_priv->work_list);
919 queue_work(iwcm_wq, &work->work);
920 } else
921 list_add_tail(&work->list, &cm_id_priv->work_list);
922out:
923 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
924 return ret;
925}
926
927static int iwcm_init_qp_init_attr(struct iwcm_id_private *cm_id_priv,
928 struct ib_qp_attr *qp_attr,
929 int *qp_attr_mask)
930{
931 unsigned long flags;
932 int ret;
933
934 spin_lock_irqsave(&cm_id_priv->lock, flags);
935 switch (cm_id_priv->state) {
936 case IW_CM_STATE_IDLE:
937 case IW_CM_STATE_CONN_SENT:
938 case IW_CM_STATE_CONN_RECV:
939 case IW_CM_STATE_ESTABLISHED:
940 *qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS;
941 qp_attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE |
942 IB_ACCESS_REMOTE_WRITE|
943 IB_ACCESS_REMOTE_READ;
944 ret = 0;
945 break;
946 default:
947 ret = -EINVAL;
948 break;
949 }
950 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
951 return ret;
952}
953
954static int iwcm_init_qp_rts_attr(struct iwcm_id_private *cm_id_priv,
955 struct ib_qp_attr *qp_attr,
956 int *qp_attr_mask)
957{
958 unsigned long flags;
959 int ret;
960
961 spin_lock_irqsave(&cm_id_priv->lock, flags);
962 switch (cm_id_priv->state) {
963 case IW_CM_STATE_IDLE:
964 case IW_CM_STATE_CONN_SENT:
965 case IW_CM_STATE_CONN_RECV:
966 case IW_CM_STATE_ESTABLISHED:
967 *qp_attr_mask = 0;
968 ret = 0;
969 break;
970 default:
971 ret = -EINVAL;
972 break;
973 }
974 spin_unlock_irqrestore(&cm_id_priv->lock, flags);
975 return ret;
976}
977
978int iw_cm_init_qp_attr(struct iw_cm_id *cm_id,
979 struct ib_qp_attr *qp_attr,
980 int *qp_attr_mask)
981{
982 struct iwcm_id_private *cm_id_priv;
983 int ret;
984
985 cm_id_priv = container_of(cm_id, struct iwcm_id_private, id);
986 switch (qp_attr->qp_state) {
987 case IB_QPS_INIT:
988 case IB_QPS_RTR:
989 ret = iwcm_init_qp_init_attr(cm_id_priv,
990 qp_attr, qp_attr_mask);
991 break;
992 case IB_QPS_RTS:
993 ret = iwcm_init_qp_rts_attr(cm_id_priv,
994 qp_attr, qp_attr_mask);
995 break;
996 default:
997 ret = -EINVAL;
998 break;
999 }
1000 return ret;
1001}
1002EXPORT_SYMBOL(iw_cm_init_qp_attr);
1003
1004static int __init iw_cm_init(void)
1005{
1006 iwcm_wq = create_singlethread_workqueue("iw_cm_wq");
1007 if (!iwcm_wq)
1008 return -ENOMEM;
1009
1010 return 0;
1011}
1012
1013static void __exit iw_cm_cleanup(void)
1014{
1015 destroy_workqueue(iwcm_wq);
1016}
1017
1018module_init(iw_cm_init);
1019module_exit(iw_cm_cleanup);
diff --git a/drivers/infiniband/core/iwcm.h b/drivers/infiniband/core/iwcm.h
new file mode 100644
index 000000000000..3f6cc82564c8
--- /dev/null
+++ b/drivers/infiniband/core/iwcm.h
@@ -0,0 +1,62 @@
1/*
2 * Copyright (c) 2005 Network Appliance, Inc. All rights reserved.
3 * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
10 *
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
13 * conditions are met:
14 *
15 * - Redistributions of source code must retain the above
16 * copyright notice, this list of conditions and the following
17 * disclaimer.
18 *
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials
22 * provided with the distribution.
23 *
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31 * SOFTWARE.
32 */
33#ifndef IWCM_H
34#define IWCM_H
35
36enum iw_cm_state {
37 IW_CM_STATE_IDLE, /* unbound, inactive */
38 IW_CM_STATE_LISTEN, /* listen waiting for connect */
39 IW_CM_STATE_CONN_RECV, /* inbound waiting for user accept */
40 IW_CM_STATE_CONN_SENT, /* outbound waiting for peer accept */
41 IW_CM_STATE_ESTABLISHED, /* established */
42 IW_CM_STATE_CLOSING, /* disconnect */
43 IW_CM_STATE_DESTROYING /* object being deleted */
44};
45
46struct iwcm_id_private {
47 struct iw_cm_id id;
48 enum iw_cm_state state;
49 unsigned long flags;
50 struct ib_qp *qp;
51 struct completion destroy_comp;
52 wait_queue_head_t connect_wait;
53 struct list_head work_list;
54 spinlock_t lock;
55 atomic_t refcount;
56 struct list_head work_free_list;
57};
58
59#define IWCM_F_CALLBACK_DESTROY 1
60#define IWCM_F_CONNECT_WAIT 2
61
62#endif /* IWCM_H */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-21 17:29:48 -0500