xref: /linux/drivers/infiniband/core/ucma.c (revision 12871a0bd67dd4db4418e1daafcd46e9d329ef10)
1 /*
2  * Copyright (c) 2005-2006 Intel Corporation.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *	copyright notice, this list of conditions and the following
16  *	disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *	copyright notice, this list of conditions and the following
20  *	disclaimer in the documentation and/or other materials
21  *	provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/completion.h>
34 #include <linux/file.h>
35 #include <linux/mutex.h>
36 #include <linux/poll.h>
37 #include <linux/sched.h>
38 #include <linux/idr.h>
39 #include <linux/in.h>
40 #include <linux/in6.h>
41 #include <linux/miscdevice.h>
42 #include <linux/slab.h>
43 #include <linux/sysctl.h>
44 
45 #include <rdma/rdma_user_cm.h>
46 #include <rdma/ib_marshall.h>
47 #include <rdma/rdma_cm.h>
48 #include <rdma/rdma_cm_ib.h>
49 
50 MODULE_AUTHOR("Sean Hefty");
51 MODULE_DESCRIPTION("RDMA Userspace Connection Manager Access");
52 MODULE_LICENSE("Dual BSD/GPL");
53 
54 static unsigned int max_backlog = 1024;
55 
56 static struct ctl_table_header *ucma_ctl_table_hdr;
57 static ctl_table ucma_ctl_table[] = {
58 	{
59 		.procname	= "max_backlog",
60 		.data		= &max_backlog,
61 		.maxlen		= sizeof max_backlog,
62 		.mode		= 0644,
63 		.proc_handler	= proc_dointvec,
64 	},
65 	{ }
66 };
67 
68 static struct ctl_path ucma_ctl_path[] = {
69 	{ .procname = "net" },
70 	{ .procname = "rdma_ucm" },
71 	{ }
72 };
73 
74 struct ucma_file {
75 	struct mutex		mut;
76 	struct file		*filp;
77 	struct list_head	ctx_list;
78 	struct list_head	event_list;
79 	wait_queue_head_t	poll_wait;
80 };
81 
82 struct ucma_context {
83 	int			id;
84 	struct completion	comp;
85 	atomic_t		ref;
86 	int			events_reported;
87 	int			backlog;
88 
89 	struct ucma_file	*file;
90 	struct rdma_cm_id	*cm_id;
91 	u64			uid;
92 
93 	struct list_head	list;
94 	struct list_head	mc_list;
95 };
96 
97 struct ucma_multicast {
98 	struct ucma_context	*ctx;
99 	int			id;
100 	int			events_reported;
101 
102 	u64			uid;
103 	struct list_head	list;
104 	struct sockaddr_storage	addr;
105 };
106 
107 struct ucma_event {
108 	struct ucma_context	*ctx;
109 	struct ucma_multicast	*mc;
110 	struct list_head	list;
111 	struct rdma_cm_id	*cm_id;
112 	struct rdma_ucm_event_resp resp;
113 };
114 
115 static DEFINE_MUTEX(mut);
116 static DEFINE_IDR(ctx_idr);
117 static DEFINE_IDR(multicast_idr);
118 
119 static inline struct ucma_context *_ucma_find_context(int id,
120 						      struct ucma_file *file)
121 {
122 	struct ucma_context *ctx;
123 
124 	ctx = idr_find(&ctx_idr, id);
125 	if (!ctx)
126 		ctx = ERR_PTR(-ENOENT);
127 	else if (ctx->file != file)
128 		ctx = ERR_PTR(-EINVAL);
129 	return ctx;
130 }
131 
132 static struct ucma_context *ucma_get_ctx(struct ucma_file *file, int id)
133 {
134 	struct ucma_context *ctx;
135 
136 	mutex_lock(&mut);
137 	ctx = _ucma_find_context(id, file);
138 	if (!IS_ERR(ctx))
139 		atomic_inc(&ctx->ref);
140 	mutex_unlock(&mut);
141 	return ctx;
142 }
143 
144 static void ucma_put_ctx(struct ucma_context *ctx)
145 {
146 	if (atomic_dec_and_test(&ctx->ref))
147 		complete(&ctx->comp);
148 }
149 
150 static struct ucma_context *ucma_alloc_ctx(struct ucma_file *file)
151 {
152 	struct ucma_context *ctx;
153 	int ret;
154 
155 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
156 	if (!ctx)
157 		return NULL;
158 
159 	atomic_set(&ctx->ref, 1);
160 	init_completion(&ctx->comp);
161 	INIT_LIST_HEAD(&ctx->mc_list);
162 	ctx->file = file;
163 
164 	do {
165 		ret = idr_pre_get(&ctx_idr, GFP_KERNEL);
166 		if (!ret)
167 			goto error;
168 
169 		mutex_lock(&mut);
170 		ret = idr_get_new(&ctx_idr, ctx, &ctx->id);
171 		mutex_unlock(&mut);
172 	} while (ret == -EAGAIN);
173 
174 	if (ret)
175 		goto error;
176 
177 	list_add_tail(&ctx->list, &file->ctx_list);
178 	return ctx;
179 
180 error:
181 	kfree(ctx);
182 	return NULL;
183 }
184 
185 static struct ucma_multicast* ucma_alloc_multicast(struct ucma_context *ctx)
186 {
187 	struct ucma_multicast *mc;
188 	int ret;
189 
190 	mc = kzalloc(sizeof(*mc), GFP_KERNEL);
191 	if (!mc)
192 		return NULL;
193 
194 	do {
195 		ret = idr_pre_get(&multicast_idr, GFP_KERNEL);
196 		if (!ret)
197 			goto error;
198 
199 		mutex_lock(&mut);
200 		ret = idr_get_new(&multicast_idr, mc, &mc->id);
201 		mutex_unlock(&mut);
202 	} while (ret == -EAGAIN);
203 
204 	if (ret)
205 		goto error;
206 
207 	mc->ctx = ctx;
208 	list_add_tail(&mc->list, &ctx->mc_list);
209 	return mc;
210 
211 error:
212 	kfree(mc);
213 	return NULL;
214 }
215 
216 static void ucma_copy_conn_event(struct rdma_ucm_conn_param *dst,
217 				 struct rdma_conn_param *src)
218 {
219 	if (src->private_data_len)
220 		memcpy(dst->private_data, src->private_data,
221 		       src->private_data_len);
222 	dst->private_data_len = src->private_data_len;
223 	dst->responder_resources =src->responder_resources;
224 	dst->initiator_depth = src->initiator_depth;
225 	dst->flow_control = src->flow_control;
226 	dst->retry_count = src->retry_count;
227 	dst->rnr_retry_count = src->rnr_retry_count;
228 	dst->srq = src->srq;
229 	dst->qp_num = src->qp_num;
230 }
231 
232 static void ucma_copy_ud_event(struct rdma_ucm_ud_param *dst,
233 			       struct rdma_ud_param *src)
234 {
235 	if (src->private_data_len)
236 		memcpy(dst->private_data, src->private_data,
237 		       src->private_data_len);
238 	dst->private_data_len = src->private_data_len;
239 	ib_copy_ah_attr_to_user(&dst->ah_attr, &src->ah_attr);
240 	dst->qp_num = src->qp_num;
241 	dst->qkey = src->qkey;
242 }
243 
244 static void ucma_set_event_context(struct ucma_context *ctx,
245 				   struct rdma_cm_event *event,
246 				   struct ucma_event *uevent)
247 {
248 	uevent->ctx = ctx;
249 	switch (event->event) {
250 	case RDMA_CM_EVENT_MULTICAST_JOIN:
251 	case RDMA_CM_EVENT_MULTICAST_ERROR:
252 		uevent->mc = (struct ucma_multicast *)
253 			     event->param.ud.private_data;
254 		uevent->resp.uid = uevent->mc->uid;
255 		uevent->resp.id = uevent->mc->id;
256 		break;
257 	default:
258 		uevent->resp.uid = ctx->uid;
259 		uevent->resp.id = ctx->id;
260 		break;
261 	}
262 }
263 
264 static int ucma_event_handler(struct rdma_cm_id *cm_id,
265 			      struct rdma_cm_event *event)
266 {
267 	struct ucma_event *uevent;
268 	struct ucma_context *ctx = cm_id->context;
269 	int ret = 0;
270 
271 	uevent = kzalloc(sizeof(*uevent), GFP_KERNEL);
272 	if (!uevent)
273 		return event->event == RDMA_CM_EVENT_CONNECT_REQUEST;
274 
275 	uevent->cm_id = cm_id;
276 	ucma_set_event_context(ctx, event, uevent);
277 	uevent->resp.event = event->event;
278 	uevent->resp.status = event->status;
279 	if (cm_id->ps == RDMA_PS_UDP || cm_id->ps == RDMA_PS_IPOIB)
280 		ucma_copy_ud_event(&uevent->resp.param.ud, &event->param.ud);
281 	else
282 		ucma_copy_conn_event(&uevent->resp.param.conn,
283 				     &event->param.conn);
284 
285 	mutex_lock(&ctx->file->mut);
286 	if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST) {
287 		if (!ctx->backlog) {
288 			ret = -ENOMEM;
289 			kfree(uevent);
290 			goto out;
291 		}
292 		ctx->backlog--;
293 	} else if (!ctx->uid) {
294 		/*
295 		 * We ignore events for new connections until userspace has set
296 		 * their context.  This can only happen if an error occurs on a
297 		 * new connection before the user accepts it.  This is okay,
298 		 * since the accept will just fail later.
299 		 */
300 		kfree(uevent);
301 		goto out;
302 	}
303 
304 	list_add_tail(&uevent->list, &ctx->file->event_list);
305 	wake_up_interruptible(&ctx->file->poll_wait);
306 out:
307 	mutex_unlock(&ctx->file->mut);
308 	return ret;
309 }
310 
311 static ssize_t ucma_get_event(struct ucma_file *file, const char __user *inbuf,
312 			      int in_len, int out_len)
313 {
314 	struct ucma_context *ctx;
315 	struct rdma_ucm_get_event cmd;
316 	struct ucma_event *uevent;
317 	int ret = 0;
318 	DEFINE_WAIT(wait);
319 
320 	if (out_len < sizeof uevent->resp)
321 		return -ENOSPC;
322 
323 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
324 		return -EFAULT;
325 
326 	mutex_lock(&file->mut);
327 	while (list_empty(&file->event_list)) {
328 		mutex_unlock(&file->mut);
329 
330 		if (file->filp->f_flags & O_NONBLOCK)
331 			return -EAGAIN;
332 
333 		if (wait_event_interruptible(file->poll_wait,
334 					     !list_empty(&file->event_list)))
335 			return -ERESTARTSYS;
336 
337 		mutex_lock(&file->mut);
338 	}
339 
340 	uevent = list_entry(file->event_list.next, struct ucma_event, list);
341 
342 	if (uevent->resp.event == RDMA_CM_EVENT_CONNECT_REQUEST) {
343 		ctx = ucma_alloc_ctx(file);
344 		if (!ctx) {
345 			ret = -ENOMEM;
346 			goto done;
347 		}
348 		uevent->ctx->backlog++;
349 		ctx->cm_id = uevent->cm_id;
350 		ctx->cm_id->context = ctx;
351 		uevent->resp.id = ctx->id;
352 	}
353 
354 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
355 			 &uevent->resp, sizeof uevent->resp)) {
356 		ret = -EFAULT;
357 		goto done;
358 	}
359 
360 	list_del(&uevent->list);
361 	uevent->ctx->events_reported++;
362 	if (uevent->mc)
363 		uevent->mc->events_reported++;
364 	kfree(uevent);
365 done:
366 	mutex_unlock(&file->mut);
367 	return ret;
368 }
369 
370 static int ucma_get_qp_type(struct rdma_ucm_create_id *cmd, enum ib_qp_type *qp_type)
371 {
372 	switch (cmd->ps) {
373 	case RDMA_PS_TCP:
374 		*qp_type = IB_QPT_RC;
375 		return 0;
376 	case RDMA_PS_UDP:
377 	case RDMA_PS_IPOIB:
378 		*qp_type = IB_QPT_UD;
379 		return 0;
380 	default:
381 		return -EINVAL;
382 	}
383 }
384 
385 static ssize_t ucma_create_id(struct ucma_file *file, const char __user *inbuf,
386 			      int in_len, int out_len)
387 {
388 	struct rdma_ucm_create_id cmd;
389 	struct rdma_ucm_create_id_resp resp;
390 	struct ucma_context *ctx;
391 	enum ib_qp_type qp_type;
392 	int ret;
393 
394 	if (out_len < sizeof(resp))
395 		return -ENOSPC;
396 
397 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
398 		return -EFAULT;
399 
400 	ret = ucma_get_qp_type(&cmd, &qp_type);
401 	if (ret)
402 		return ret;
403 
404 	mutex_lock(&file->mut);
405 	ctx = ucma_alloc_ctx(file);
406 	mutex_unlock(&file->mut);
407 	if (!ctx)
408 		return -ENOMEM;
409 
410 	ctx->uid = cmd.uid;
411 	ctx->cm_id = rdma_create_id(ucma_event_handler, ctx, cmd.ps, qp_type);
412 	if (IS_ERR(ctx->cm_id)) {
413 		ret = PTR_ERR(ctx->cm_id);
414 		goto err1;
415 	}
416 
417 	resp.id = ctx->id;
418 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
419 			 &resp, sizeof(resp))) {
420 		ret = -EFAULT;
421 		goto err2;
422 	}
423 	return 0;
424 
425 err2:
426 	rdma_destroy_id(ctx->cm_id);
427 err1:
428 	mutex_lock(&mut);
429 	idr_remove(&ctx_idr, ctx->id);
430 	mutex_unlock(&mut);
431 	kfree(ctx);
432 	return ret;
433 }
434 
435 static void ucma_cleanup_multicast(struct ucma_context *ctx)
436 {
437 	struct ucma_multicast *mc, *tmp;
438 
439 	mutex_lock(&mut);
440 	list_for_each_entry_safe(mc, tmp, &ctx->mc_list, list) {
441 		list_del(&mc->list);
442 		idr_remove(&multicast_idr, mc->id);
443 		kfree(mc);
444 	}
445 	mutex_unlock(&mut);
446 }
447 
448 static void ucma_cleanup_events(struct ucma_context *ctx)
449 {
450 	struct ucma_event *uevent, *tmp;
451 
452 	list_for_each_entry_safe(uevent, tmp, &ctx->file->event_list, list) {
453 		if (uevent->ctx != ctx)
454 			continue;
455 
456 		list_del(&uevent->list);
457 
458 		/* clear incoming connections. */
459 		if (uevent->resp.event == RDMA_CM_EVENT_CONNECT_REQUEST)
460 			rdma_destroy_id(uevent->cm_id);
461 
462 		kfree(uevent);
463 	}
464 }
465 
466 static void ucma_cleanup_mc_events(struct ucma_multicast *mc)
467 {
468 	struct ucma_event *uevent, *tmp;
469 
470 	list_for_each_entry_safe(uevent, tmp, &mc->ctx->file->event_list, list) {
471 		if (uevent->mc != mc)
472 			continue;
473 
474 		list_del(&uevent->list);
475 		kfree(uevent);
476 	}
477 }
478 
479 static int ucma_free_ctx(struct ucma_context *ctx)
480 {
481 	int events_reported;
482 
483 	/* No new events will be generated after destroying the id. */
484 	rdma_destroy_id(ctx->cm_id);
485 
486 	ucma_cleanup_multicast(ctx);
487 
488 	/* Cleanup events not yet reported to the user. */
489 	mutex_lock(&ctx->file->mut);
490 	ucma_cleanup_events(ctx);
491 	list_del(&ctx->list);
492 	mutex_unlock(&ctx->file->mut);
493 
494 	events_reported = ctx->events_reported;
495 	kfree(ctx);
496 	return events_reported;
497 }
498 
499 static ssize_t ucma_destroy_id(struct ucma_file *file, const char __user *inbuf,
500 			       int in_len, int out_len)
501 {
502 	struct rdma_ucm_destroy_id cmd;
503 	struct rdma_ucm_destroy_id_resp resp;
504 	struct ucma_context *ctx;
505 	int ret = 0;
506 
507 	if (out_len < sizeof(resp))
508 		return -ENOSPC;
509 
510 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
511 		return -EFAULT;
512 
513 	mutex_lock(&mut);
514 	ctx = _ucma_find_context(cmd.id, file);
515 	if (!IS_ERR(ctx))
516 		idr_remove(&ctx_idr, ctx->id);
517 	mutex_unlock(&mut);
518 
519 	if (IS_ERR(ctx))
520 		return PTR_ERR(ctx);
521 
522 	ucma_put_ctx(ctx);
523 	wait_for_completion(&ctx->comp);
524 	resp.events_reported = ucma_free_ctx(ctx);
525 
526 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
527 			 &resp, sizeof(resp)))
528 		ret = -EFAULT;
529 
530 	return ret;
531 }
532 
533 static ssize_t ucma_bind_addr(struct ucma_file *file, const char __user *inbuf,
534 			      int in_len, int out_len)
535 {
536 	struct rdma_ucm_bind_addr cmd;
537 	struct ucma_context *ctx;
538 	int ret;
539 
540 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
541 		return -EFAULT;
542 
543 	ctx = ucma_get_ctx(file, cmd.id);
544 	if (IS_ERR(ctx))
545 		return PTR_ERR(ctx);
546 
547 	ret = rdma_bind_addr(ctx->cm_id, (struct sockaddr *) &cmd.addr);
548 	ucma_put_ctx(ctx);
549 	return ret;
550 }
551 
552 static ssize_t ucma_resolve_addr(struct ucma_file *file,
553 				 const char __user *inbuf,
554 				 int in_len, int out_len)
555 {
556 	struct rdma_ucm_resolve_addr cmd;
557 	struct ucma_context *ctx;
558 	int ret;
559 
560 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
561 		return -EFAULT;
562 
563 	ctx = ucma_get_ctx(file, cmd.id);
564 	if (IS_ERR(ctx))
565 		return PTR_ERR(ctx);
566 
567 	ret = rdma_resolve_addr(ctx->cm_id, (struct sockaddr *) &cmd.src_addr,
568 				(struct sockaddr *) &cmd.dst_addr,
569 				cmd.timeout_ms);
570 	ucma_put_ctx(ctx);
571 	return ret;
572 }
573 
574 static ssize_t ucma_resolve_route(struct ucma_file *file,
575 				  const char __user *inbuf,
576 				  int in_len, int out_len)
577 {
578 	struct rdma_ucm_resolve_route cmd;
579 	struct ucma_context *ctx;
580 	int ret;
581 
582 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
583 		return -EFAULT;
584 
585 	ctx = ucma_get_ctx(file, cmd.id);
586 	if (IS_ERR(ctx))
587 		return PTR_ERR(ctx);
588 
589 	ret = rdma_resolve_route(ctx->cm_id, cmd.timeout_ms);
590 	ucma_put_ctx(ctx);
591 	return ret;
592 }
593 
594 static void ucma_copy_ib_route(struct rdma_ucm_query_route_resp *resp,
595 			       struct rdma_route *route)
596 {
597 	struct rdma_dev_addr *dev_addr;
598 
599 	resp->num_paths = route->num_paths;
600 	switch (route->num_paths) {
601 	case 0:
602 		dev_addr = &route->addr.dev_addr;
603 		rdma_addr_get_dgid(dev_addr,
604 				   (union ib_gid *) &resp->ib_route[0].dgid);
605 		rdma_addr_get_sgid(dev_addr,
606 				   (union ib_gid *) &resp->ib_route[0].sgid);
607 		resp->ib_route[0].pkey = cpu_to_be16(ib_addr_get_pkey(dev_addr));
608 		break;
609 	case 2:
610 		ib_copy_path_rec_to_user(&resp->ib_route[1],
611 					 &route->path_rec[1]);
612 		/* fall through */
613 	case 1:
614 		ib_copy_path_rec_to_user(&resp->ib_route[0],
615 					 &route->path_rec[0]);
616 		break;
617 	default:
618 		break;
619 	}
620 }
621 
622 static void ucma_copy_iboe_route(struct rdma_ucm_query_route_resp *resp,
623 				 struct rdma_route *route)
624 {
625 	struct rdma_dev_addr *dev_addr;
626 	struct net_device *dev;
627 	u16 vid = 0;
628 
629 	resp->num_paths = route->num_paths;
630 	switch (route->num_paths) {
631 	case 0:
632 		dev_addr = &route->addr.dev_addr;
633 		dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
634 			if (dev) {
635 				vid = rdma_vlan_dev_vlan_id(dev);
636 				dev_put(dev);
637 			}
638 
639 		iboe_mac_vlan_to_ll((union ib_gid *) &resp->ib_route[0].dgid,
640 				    dev_addr->dst_dev_addr, vid);
641 		iboe_addr_get_sgid(dev_addr,
642 				   (union ib_gid *) &resp->ib_route[0].sgid);
643 		resp->ib_route[0].pkey = cpu_to_be16(0xffff);
644 		break;
645 	case 2:
646 		ib_copy_path_rec_to_user(&resp->ib_route[1],
647 					 &route->path_rec[1]);
648 		/* fall through */
649 	case 1:
650 		ib_copy_path_rec_to_user(&resp->ib_route[0],
651 					 &route->path_rec[0]);
652 		break;
653 	default:
654 		break;
655 	}
656 }
657 
658 static void ucma_copy_iw_route(struct rdma_ucm_query_route_resp *resp,
659 			       struct rdma_route *route)
660 {
661 	struct rdma_dev_addr *dev_addr;
662 
663 	dev_addr = &route->addr.dev_addr;
664 	rdma_addr_get_dgid(dev_addr, (union ib_gid *) &resp->ib_route[0].dgid);
665 	rdma_addr_get_sgid(dev_addr, (union ib_gid *) &resp->ib_route[0].sgid);
666 }
667 
668 static ssize_t ucma_query_route(struct ucma_file *file,
669 				const char __user *inbuf,
670 				int in_len, int out_len)
671 {
672 	struct rdma_ucm_query_route cmd;
673 	struct rdma_ucm_query_route_resp resp;
674 	struct ucma_context *ctx;
675 	struct sockaddr *addr;
676 	int ret = 0;
677 
678 	if (out_len < sizeof(resp))
679 		return -ENOSPC;
680 
681 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
682 		return -EFAULT;
683 
684 	ctx = ucma_get_ctx(file, cmd.id);
685 	if (IS_ERR(ctx))
686 		return PTR_ERR(ctx);
687 
688 	memset(&resp, 0, sizeof resp);
689 	addr = (struct sockaddr *) &ctx->cm_id->route.addr.src_addr;
690 	memcpy(&resp.src_addr, addr, addr->sa_family == AF_INET ?
691 				     sizeof(struct sockaddr_in) :
692 				     sizeof(struct sockaddr_in6));
693 	addr = (struct sockaddr *) &ctx->cm_id->route.addr.dst_addr;
694 	memcpy(&resp.dst_addr, addr, addr->sa_family == AF_INET ?
695 				     sizeof(struct sockaddr_in) :
696 				     sizeof(struct sockaddr_in6));
697 	if (!ctx->cm_id->device)
698 		goto out;
699 
700 	resp.node_guid = (__force __u64) ctx->cm_id->device->node_guid;
701 	resp.port_num = ctx->cm_id->port_num;
702 	switch (rdma_node_get_transport(ctx->cm_id->device->node_type)) {
703 	case RDMA_TRANSPORT_IB:
704 		switch (rdma_port_get_link_layer(ctx->cm_id->device,
705 			ctx->cm_id->port_num)) {
706 		case IB_LINK_LAYER_INFINIBAND:
707 			ucma_copy_ib_route(&resp, &ctx->cm_id->route);
708 			break;
709 		case IB_LINK_LAYER_ETHERNET:
710 			ucma_copy_iboe_route(&resp, &ctx->cm_id->route);
711 			break;
712 		default:
713 			break;
714 		}
715 		break;
716 	case RDMA_TRANSPORT_IWARP:
717 		ucma_copy_iw_route(&resp, &ctx->cm_id->route);
718 		break;
719 	default:
720 		break;
721 	}
722 
723 out:
724 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
725 			 &resp, sizeof(resp)))
726 		ret = -EFAULT;
727 
728 	ucma_put_ctx(ctx);
729 	return ret;
730 }
731 
732 static void ucma_copy_conn_param(struct rdma_conn_param *dst,
733 				 struct rdma_ucm_conn_param *src)
734 {
735 	dst->private_data = src->private_data;
736 	dst->private_data_len = src->private_data_len;
737 	dst->responder_resources =src->responder_resources;
738 	dst->initiator_depth = src->initiator_depth;
739 	dst->flow_control = src->flow_control;
740 	dst->retry_count = src->retry_count;
741 	dst->rnr_retry_count = src->rnr_retry_count;
742 	dst->srq = src->srq;
743 	dst->qp_num = src->qp_num;
744 }
745 
746 static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf,
747 			    int in_len, int out_len)
748 {
749 	struct rdma_ucm_connect cmd;
750 	struct rdma_conn_param conn_param;
751 	struct ucma_context *ctx;
752 	int ret;
753 
754 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
755 		return -EFAULT;
756 
757 	if (!cmd.conn_param.valid)
758 		return -EINVAL;
759 
760 	ctx = ucma_get_ctx(file, cmd.id);
761 	if (IS_ERR(ctx))
762 		return PTR_ERR(ctx);
763 
764 	ucma_copy_conn_param(&conn_param, &cmd.conn_param);
765 	ret = rdma_connect(ctx->cm_id, &conn_param);
766 	ucma_put_ctx(ctx);
767 	return ret;
768 }
769 
770 static ssize_t ucma_listen(struct ucma_file *file, const char __user *inbuf,
771 			   int in_len, int out_len)
772 {
773 	struct rdma_ucm_listen cmd;
774 	struct ucma_context *ctx;
775 	int ret;
776 
777 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
778 		return -EFAULT;
779 
780 	ctx = ucma_get_ctx(file, cmd.id);
781 	if (IS_ERR(ctx))
782 		return PTR_ERR(ctx);
783 
784 	ctx->backlog = cmd.backlog > 0 && cmd.backlog < max_backlog ?
785 		       cmd.backlog : max_backlog;
786 	ret = rdma_listen(ctx->cm_id, ctx->backlog);
787 	ucma_put_ctx(ctx);
788 	return ret;
789 }
790 
791 static ssize_t ucma_accept(struct ucma_file *file, const char __user *inbuf,
792 			   int in_len, int out_len)
793 {
794 	struct rdma_ucm_accept cmd;
795 	struct rdma_conn_param conn_param;
796 	struct ucma_context *ctx;
797 	int ret;
798 
799 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
800 		return -EFAULT;
801 
802 	ctx = ucma_get_ctx(file, cmd.id);
803 	if (IS_ERR(ctx))
804 		return PTR_ERR(ctx);
805 
806 	if (cmd.conn_param.valid) {
807 		ctx->uid = cmd.uid;
808 		ucma_copy_conn_param(&conn_param, &cmd.conn_param);
809 		ret = rdma_accept(ctx->cm_id, &conn_param);
810 	} else
811 		ret = rdma_accept(ctx->cm_id, NULL);
812 
813 	ucma_put_ctx(ctx);
814 	return ret;
815 }
816 
817 static ssize_t ucma_reject(struct ucma_file *file, const char __user *inbuf,
818 			   int in_len, int out_len)
819 {
820 	struct rdma_ucm_reject cmd;
821 	struct ucma_context *ctx;
822 	int ret;
823 
824 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
825 		return -EFAULT;
826 
827 	ctx = ucma_get_ctx(file, cmd.id);
828 	if (IS_ERR(ctx))
829 		return PTR_ERR(ctx);
830 
831 	ret = rdma_reject(ctx->cm_id, cmd.private_data, cmd.private_data_len);
832 	ucma_put_ctx(ctx);
833 	return ret;
834 }
835 
836 static ssize_t ucma_disconnect(struct ucma_file *file, const char __user *inbuf,
837 			       int in_len, int out_len)
838 {
839 	struct rdma_ucm_disconnect cmd;
840 	struct ucma_context *ctx;
841 	int ret;
842 
843 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
844 		return -EFAULT;
845 
846 	ctx = ucma_get_ctx(file, cmd.id);
847 	if (IS_ERR(ctx))
848 		return PTR_ERR(ctx);
849 
850 	ret = rdma_disconnect(ctx->cm_id);
851 	ucma_put_ctx(ctx);
852 	return ret;
853 }
854 
855 static ssize_t ucma_init_qp_attr(struct ucma_file *file,
856 				 const char __user *inbuf,
857 				 int in_len, int out_len)
858 {
859 	struct rdma_ucm_init_qp_attr cmd;
860 	struct ib_uverbs_qp_attr resp;
861 	struct ucma_context *ctx;
862 	struct ib_qp_attr qp_attr;
863 	int ret;
864 
865 	if (out_len < sizeof(resp))
866 		return -ENOSPC;
867 
868 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
869 		return -EFAULT;
870 
871 	ctx = ucma_get_ctx(file, cmd.id);
872 	if (IS_ERR(ctx))
873 		return PTR_ERR(ctx);
874 
875 	resp.qp_attr_mask = 0;
876 	memset(&qp_attr, 0, sizeof qp_attr);
877 	qp_attr.qp_state = cmd.qp_state;
878 	ret = rdma_init_qp_attr(ctx->cm_id, &qp_attr, &resp.qp_attr_mask);
879 	if (ret)
880 		goto out;
881 
882 	ib_copy_qp_attr_to_user(&resp, &qp_attr);
883 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
884 			 &resp, sizeof(resp)))
885 		ret = -EFAULT;
886 
887 out:
888 	ucma_put_ctx(ctx);
889 	return ret;
890 }
891 
892 static int ucma_set_option_id(struct ucma_context *ctx, int optname,
893 			      void *optval, size_t optlen)
894 {
895 	int ret = 0;
896 
897 	switch (optname) {
898 	case RDMA_OPTION_ID_TOS:
899 		if (optlen != sizeof(u8)) {
900 			ret = -EINVAL;
901 			break;
902 		}
903 		rdma_set_service_type(ctx->cm_id, *((u8 *) optval));
904 		break;
905 	case RDMA_OPTION_ID_REUSEADDR:
906 		if (optlen != sizeof(int)) {
907 			ret = -EINVAL;
908 			break;
909 		}
910 		ret = rdma_set_reuseaddr(ctx->cm_id, *((int *) optval) ? 1 : 0);
911 		break;
912 	default:
913 		ret = -ENOSYS;
914 	}
915 
916 	return ret;
917 }
918 
919 static int ucma_set_ib_path(struct ucma_context *ctx,
920 			    struct ib_path_rec_data *path_data, size_t optlen)
921 {
922 	struct ib_sa_path_rec sa_path;
923 	struct rdma_cm_event event;
924 	int ret;
925 
926 	if (optlen % sizeof(*path_data))
927 		return -EINVAL;
928 
929 	for (; optlen; optlen -= sizeof(*path_data), path_data++) {
930 		if (path_data->flags == (IB_PATH_GMP | IB_PATH_PRIMARY |
931 					 IB_PATH_BIDIRECTIONAL))
932 			break;
933 	}
934 
935 	if (!optlen)
936 		return -EINVAL;
937 
938 	ib_sa_unpack_path(path_data->path_rec, &sa_path);
939 	ret = rdma_set_ib_paths(ctx->cm_id, &sa_path, 1);
940 	if (ret)
941 		return ret;
942 
943 	memset(&event, 0, sizeof event);
944 	event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
945 	return ucma_event_handler(ctx->cm_id, &event);
946 }
947 
948 static int ucma_set_option_ib(struct ucma_context *ctx, int optname,
949 			      void *optval, size_t optlen)
950 {
951 	int ret;
952 
953 	switch (optname) {
954 	case RDMA_OPTION_IB_PATH:
955 		ret = ucma_set_ib_path(ctx, optval, optlen);
956 		break;
957 	default:
958 		ret = -ENOSYS;
959 	}
960 
961 	return ret;
962 }
963 
964 static int ucma_set_option_level(struct ucma_context *ctx, int level,
965 				 int optname, void *optval, size_t optlen)
966 {
967 	int ret;
968 
969 	switch (level) {
970 	case RDMA_OPTION_ID:
971 		ret = ucma_set_option_id(ctx, optname, optval, optlen);
972 		break;
973 	case RDMA_OPTION_IB:
974 		ret = ucma_set_option_ib(ctx, optname, optval, optlen);
975 		break;
976 	default:
977 		ret = -ENOSYS;
978 	}
979 
980 	return ret;
981 }
982 
983 static ssize_t ucma_set_option(struct ucma_file *file, const char __user *inbuf,
984 			       int in_len, int out_len)
985 {
986 	struct rdma_ucm_set_option cmd;
987 	struct ucma_context *ctx;
988 	void *optval;
989 	int ret;
990 
991 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
992 		return -EFAULT;
993 
994 	ctx = ucma_get_ctx(file, cmd.id);
995 	if (IS_ERR(ctx))
996 		return PTR_ERR(ctx);
997 
998 	optval = kmalloc(cmd.optlen, GFP_KERNEL);
999 	if (!optval) {
1000 		ret = -ENOMEM;
1001 		goto out1;
1002 	}
1003 
1004 	if (copy_from_user(optval, (void __user *) (unsigned long) cmd.optval,
1005 			   cmd.optlen)) {
1006 		ret = -EFAULT;
1007 		goto out2;
1008 	}
1009 
1010 	ret = ucma_set_option_level(ctx, cmd.level, cmd.optname, optval,
1011 				    cmd.optlen);
1012 out2:
1013 	kfree(optval);
1014 out1:
1015 	ucma_put_ctx(ctx);
1016 	return ret;
1017 }
1018 
1019 static ssize_t ucma_notify(struct ucma_file *file, const char __user *inbuf,
1020 			   int in_len, int out_len)
1021 {
1022 	struct rdma_ucm_notify cmd;
1023 	struct ucma_context *ctx;
1024 	int ret;
1025 
1026 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1027 		return -EFAULT;
1028 
1029 	ctx = ucma_get_ctx(file, cmd.id);
1030 	if (IS_ERR(ctx))
1031 		return PTR_ERR(ctx);
1032 
1033 	ret = rdma_notify(ctx->cm_id, (enum ib_event_type) cmd.event);
1034 	ucma_put_ctx(ctx);
1035 	return ret;
1036 }
1037 
1038 static ssize_t ucma_join_multicast(struct ucma_file *file,
1039 				   const char __user *inbuf,
1040 				   int in_len, int out_len)
1041 {
1042 	struct rdma_ucm_join_mcast cmd;
1043 	struct rdma_ucm_create_id_resp resp;
1044 	struct ucma_context *ctx;
1045 	struct ucma_multicast *mc;
1046 	int ret;
1047 
1048 	if (out_len < sizeof(resp))
1049 		return -ENOSPC;
1050 
1051 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1052 		return -EFAULT;
1053 
1054 	ctx = ucma_get_ctx(file, cmd.id);
1055 	if (IS_ERR(ctx))
1056 		return PTR_ERR(ctx);
1057 
1058 	mutex_lock(&file->mut);
1059 	mc = ucma_alloc_multicast(ctx);
1060 	if (!mc) {
1061 		ret = -ENOMEM;
1062 		goto err1;
1063 	}
1064 
1065 	mc->uid = cmd.uid;
1066 	memcpy(&mc->addr, &cmd.addr, sizeof cmd.addr);
1067 	ret = rdma_join_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr, mc);
1068 	if (ret)
1069 		goto err2;
1070 
1071 	resp.id = mc->id;
1072 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
1073 			 &resp, sizeof(resp))) {
1074 		ret = -EFAULT;
1075 		goto err3;
1076 	}
1077 
1078 	mutex_unlock(&file->mut);
1079 	ucma_put_ctx(ctx);
1080 	return 0;
1081 
1082 err3:
1083 	rdma_leave_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr);
1084 	ucma_cleanup_mc_events(mc);
1085 err2:
1086 	mutex_lock(&mut);
1087 	idr_remove(&multicast_idr, mc->id);
1088 	mutex_unlock(&mut);
1089 	list_del(&mc->list);
1090 	kfree(mc);
1091 err1:
1092 	mutex_unlock(&file->mut);
1093 	ucma_put_ctx(ctx);
1094 	return ret;
1095 }
1096 
1097 static ssize_t ucma_leave_multicast(struct ucma_file *file,
1098 				    const char __user *inbuf,
1099 				    int in_len, int out_len)
1100 {
1101 	struct rdma_ucm_destroy_id cmd;
1102 	struct rdma_ucm_destroy_id_resp resp;
1103 	struct ucma_multicast *mc;
1104 	int ret = 0;
1105 
1106 	if (out_len < sizeof(resp))
1107 		return -ENOSPC;
1108 
1109 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1110 		return -EFAULT;
1111 
1112 	mutex_lock(&mut);
1113 	mc = idr_find(&multicast_idr, cmd.id);
1114 	if (!mc)
1115 		mc = ERR_PTR(-ENOENT);
1116 	else if (mc->ctx->file != file)
1117 		mc = ERR_PTR(-EINVAL);
1118 	else {
1119 		idr_remove(&multicast_idr, mc->id);
1120 		atomic_inc(&mc->ctx->ref);
1121 	}
1122 	mutex_unlock(&mut);
1123 
1124 	if (IS_ERR(mc)) {
1125 		ret = PTR_ERR(mc);
1126 		goto out;
1127 	}
1128 
1129 	rdma_leave_multicast(mc->ctx->cm_id, (struct sockaddr *) &mc->addr);
1130 	mutex_lock(&mc->ctx->file->mut);
1131 	ucma_cleanup_mc_events(mc);
1132 	list_del(&mc->list);
1133 	mutex_unlock(&mc->ctx->file->mut);
1134 
1135 	ucma_put_ctx(mc->ctx);
1136 	resp.events_reported = mc->events_reported;
1137 	kfree(mc);
1138 
1139 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
1140 			 &resp, sizeof(resp)))
1141 		ret = -EFAULT;
1142 out:
1143 	return ret;
1144 }
1145 
1146 static void ucma_lock_files(struct ucma_file *file1, struct ucma_file *file2)
1147 {
1148 	/* Acquire mutex's based on pointer comparison to prevent deadlock. */
1149 	if (file1 < file2) {
1150 		mutex_lock(&file1->mut);
1151 		mutex_lock(&file2->mut);
1152 	} else {
1153 		mutex_lock(&file2->mut);
1154 		mutex_lock(&file1->mut);
1155 	}
1156 }
1157 
1158 static void ucma_unlock_files(struct ucma_file *file1, struct ucma_file *file2)
1159 {
1160 	if (file1 < file2) {
1161 		mutex_unlock(&file2->mut);
1162 		mutex_unlock(&file1->mut);
1163 	} else {
1164 		mutex_unlock(&file1->mut);
1165 		mutex_unlock(&file2->mut);
1166 	}
1167 }
1168 
1169 static void ucma_move_events(struct ucma_context *ctx, struct ucma_file *file)
1170 {
1171 	struct ucma_event *uevent, *tmp;
1172 
1173 	list_for_each_entry_safe(uevent, tmp, &ctx->file->event_list, list)
1174 		if (uevent->ctx == ctx)
1175 			list_move_tail(&uevent->list, &file->event_list);
1176 }
1177 
1178 static ssize_t ucma_migrate_id(struct ucma_file *new_file,
1179 			       const char __user *inbuf,
1180 			       int in_len, int out_len)
1181 {
1182 	struct rdma_ucm_migrate_id cmd;
1183 	struct rdma_ucm_migrate_resp resp;
1184 	struct ucma_context *ctx;
1185 	struct file *filp;
1186 	struct ucma_file *cur_file;
1187 	int ret = 0;
1188 
1189 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1190 		return -EFAULT;
1191 
1192 	/* Get current fd to protect against it being closed */
1193 	filp = fget(cmd.fd);
1194 	if (!filp)
1195 		return -ENOENT;
1196 
1197 	/* Validate current fd and prevent destruction of id. */
1198 	ctx = ucma_get_ctx(filp->private_data, cmd.id);
1199 	if (IS_ERR(ctx)) {
1200 		ret = PTR_ERR(ctx);
1201 		goto file_put;
1202 	}
1203 
1204 	cur_file = ctx->file;
1205 	if (cur_file == new_file) {
1206 		resp.events_reported = ctx->events_reported;
1207 		goto response;
1208 	}
1209 
1210 	/*
1211 	 * Migrate events between fd's, maintaining order, and avoiding new
1212 	 * events being added before existing events.
1213 	 */
1214 	ucma_lock_files(cur_file, new_file);
1215 	mutex_lock(&mut);
1216 
1217 	list_move_tail(&ctx->list, &new_file->ctx_list);
1218 	ucma_move_events(ctx, new_file);
1219 	ctx->file = new_file;
1220 	resp.events_reported = ctx->events_reported;
1221 
1222 	mutex_unlock(&mut);
1223 	ucma_unlock_files(cur_file, new_file);
1224 
1225 response:
1226 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
1227 			 &resp, sizeof(resp)))
1228 		ret = -EFAULT;
1229 
1230 	ucma_put_ctx(ctx);
1231 file_put:
1232 	fput(filp);
1233 	return ret;
1234 }
1235 
1236 static ssize_t (*ucma_cmd_table[])(struct ucma_file *file,
1237 				   const char __user *inbuf,
1238 				   int in_len, int out_len) = {
1239 	[RDMA_USER_CM_CMD_CREATE_ID]	= ucma_create_id,
1240 	[RDMA_USER_CM_CMD_DESTROY_ID]	= ucma_destroy_id,
1241 	[RDMA_USER_CM_CMD_BIND_ADDR]	= ucma_bind_addr,
1242 	[RDMA_USER_CM_CMD_RESOLVE_ADDR]	= ucma_resolve_addr,
1243 	[RDMA_USER_CM_CMD_RESOLVE_ROUTE]= ucma_resolve_route,
1244 	[RDMA_USER_CM_CMD_QUERY_ROUTE]	= ucma_query_route,
1245 	[RDMA_USER_CM_CMD_CONNECT]	= ucma_connect,
1246 	[RDMA_USER_CM_CMD_LISTEN]	= ucma_listen,
1247 	[RDMA_USER_CM_CMD_ACCEPT]	= ucma_accept,
1248 	[RDMA_USER_CM_CMD_REJECT]	= ucma_reject,
1249 	[RDMA_USER_CM_CMD_DISCONNECT]	= ucma_disconnect,
1250 	[RDMA_USER_CM_CMD_INIT_QP_ATTR]	= ucma_init_qp_attr,
1251 	[RDMA_USER_CM_CMD_GET_EVENT]	= ucma_get_event,
1252 	[RDMA_USER_CM_CMD_GET_OPTION]	= NULL,
1253 	[RDMA_USER_CM_CMD_SET_OPTION]	= ucma_set_option,
1254 	[RDMA_USER_CM_CMD_NOTIFY]	= ucma_notify,
1255 	[RDMA_USER_CM_CMD_JOIN_MCAST]	= ucma_join_multicast,
1256 	[RDMA_USER_CM_CMD_LEAVE_MCAST]	= ucma_leave_multicast,
1257 	[RDMA_USER_CM_CMD_MIGRATE_ID]	= ucma_migrate_id
1258 };
1259 
1260 static ssize_t ucma_write(struct file *filp, const char __user *buf,
1261 			  size_t len, loff_t *pos)
1262 {
1263 	struct ucma_file *file = filp->private_data;
1264 	struct rdma_ucm_cmd_hdr hdr;
1265 	ssize_t ret;
1266 
1267 	if (len < sizeof(hdr))
1268 		return -EINVAL;
1269 
1270 	if (copy_from_user(&hdr, buf, sizeof(hdr)))
1271 		return -EFAULT;
1272 
1273 	if (hdr.cmd < 0 || hdr.cmd >= ARRAY_SIZE(ucma_cmd_table))
1274 		return -EINVAL;
1275 
1276 	if (hdr.in + sizeof(hdr) > len)
1277 		return -EINVAL;
1278 
1279 	if (!ucma_cmd_table[hdr.cmd])
1280 		return -ENOSYS;
1281 
1282 	ret = ucma_cmd_table[hdr.cmd](file, buf + sizeof(hdr), hdr.in, hdr.out);
1283 	if (!ret)
1284 		ret = len;
1285 
1286 	return ret;
1287 }
1288 
1289 static unsigned int ucma_poll(struct file *filp, struct poll_table_struct *wait)
1290 {
1291 	struct ucma_file *file = filp->private_data;
1292 	unsigned int mask = 0;
1293 
1294 	poll_wait(filp, &file->poll_wait, wait);
1295 
1296 	if (!list_empty(&file->event_list))
1297 		mask = POLLIN | POLLRDNORM;
1298 
1299 	return mask;
1300 }
1301 
1302 /*
1303  * ucma_open() does not need the BKL:
1304  *
1305  *  - no global state is referred to;
1306  *  - there is no ioctl method to race against;
1307  *  - no further module initialization is required for open to work
1308  *    after the device is registered.
1309  */
1310 static int ucma_open(struct inode *inode, struct file *filp)
1311 {
1312 	struct ucma_file *file;
1313 
1314 	file = kmalloc(sizeof *file, GFP_KERNEL);
1315 	if (!file)
1316 		return -ENOMEM;
1317 
1318 	INIT_LIST_HEAD(&file->event_list);
1319 	INIT_LIST_HEAD(&file->ctx_list);
1320 	init_waitqueue_head(&file->poll_wait);
1321 	mutex_init(&file->mut);
1322 
1323 	filp->private_data = file;
1324 	file->filp = filp;
1325 
1326 	return nonseekable_open(inode, filp);
1327 }
1328 
1329 static int ucma_close(struct inode *inode, struct file *filp)
1330 {
1331 	struct ucma_file *file = filp->private_data;
1332 	struct ucma_context *ctx, *tmp;
1333 
1334 	mutex_lock(&file->mut);
1335 	list_for_each_entry_safe(ctx, tmp, &file->ctx_list, list) {
1336 		mutex_unlock(&file->mut);
1337 
1338 		mutex_lock(&mut);
1339 		idr_remove(&ctx_idr, ctx->id);
1340 		mutex_unlock(&mut);
1341 
1342 		ucma_free_ctx(ctx);
1343 		mutex_lock(&file->mut);
1344 	}
1345 	mutex_unlock(&file->mut);
1346 	kfree(file);
1347 	return 0;
1348 }
1349 
1350 static const struct file_operations ucma_fops = {
1351 	.owner 	 = THIS_MODULE,
1352 	.open 	 = ucma_open,
1353 	.release = ucma_close,
1354 	.write	 = ucma_write,
1355 	.poll    = ucma_poll,
1356 	.llseek	 = no_llseek,
1357 };
1358 
1359 static struct miscdevice ucma_misc = {
1360 	.minor		= MISC_DYNAMIC_MINOR,
1361 	.name		= "rdma_cm",
1362 	.nodename	= "infiniband/rdma_cm",
1363 	.mode		= 0666,
1364 	.fops		= &ucma_fops,
1365 };
1366 
1367 static ssize_t show_abi_version(struct device *dev,
1368 				struct device_attribute *attr,
1369 				char *buf)
1370 {
1371 	return sprintf(buf, "%d\n", RDMA_USER_CM_ABI_VERSION);
1372 }
1373 static DEVICE_ATTR(abi_version, S_IRUGO, show_abi_version, NULL);
1374 
1375 static int __init ucma_init(void)
1376 {
1377 	int ret;
1378 
1379 	ret = misc_register(&ucma_misc);
1380 	if (ret)
1381 		return ret;
1382 
1383 	ret = device_create_file(ucma_misc.this_device, &dev_attr_abi_version);
1384 	if (ret) {
1385 		printk(KERN_ERR "rdma_ucm: couldn't create abi_version attr\n");
1386 		goto err1;
1387 	}
1388 
1389 	ucma_ctl_table_hdr = register_sysctl_paths(ucma_ctl_path, ucma_ctl_table);
1390 	if (!ucma_ctl_table_hdr) {
1391 		printk(KERN_ERR "rdma_ucm: couldn't register sysctl paths\n");
1392 		ret = -ENOMEM;
1393 		goto err2;
1394 	}
1395 	return 0;
1396 err2:
1397 	device_remove_file(ucma_misc.this_device, &dev_attr_abi_version);
1398 err1:
1399 	misc_deregister(&ucma_misc);
1400 	return ret;
1401 }
1402 
1403 static void __exit ucma_cleanup(void)
1404 {
1405 	unregister_sysctl_table(ucma_ctl_table_hdr);
1406 	device_remove_file(ucma_misc.this_device, &dev_attr_abi_version);
1407 	misc_deregister(&ucma_misc);
1408 	idr_destroy(&ctx_idr);
1409 }
1410 
1411 module_init(ucma_init);
1412 module_exit(ucma_cleanup);
1413