xref: /openbmc/linux/drivers/infiniband/core/ucma.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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 ssize_t ucma_create_id(struct ucma_file *file,
371 				const char __user *inbuf,
372 				int in_len, int out_len)
373 {
374 	struct rdma_ucm_create_id cmd;
375 	struct rdma_ucm_create_id_resp resp;
376 	struct ucma_context *ctx;
377 	int ret;
378 
379 	if (out_len < sizeof(resp))
380 		return -ENOSPC;
381 
382 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
383 		return -EFAULT;
384 
385 	mutex_lock(&file->mut);
386 	ctx = ucma_alloc_ctx(file);
387 	mutex_unlock(&file->mut);
388 	if (!ctx)
389 		return -ENOMEM;
390 
391 	ctx->uid = cmd.uid;
392 	ctx->cm_id = rdma_create_id(ucma_event_handler, ctx, cmd.ps);
393 	if (IS_ERR(ctx->cm_id)) {
394 		ret = PTR_ERR(ctx->cm_id);
395 		goto err1;
396 	}
397 
398 	resp.id = ctx->id;
399 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
400 			 &resp, sizeof(resp))) {
401 		ret = -EFAULT;
402 		goto err2;
403 	}
404 	return 0;
405 
406 err2:
407 	rdma_destroy_id(ctx->cm_id);
408 err1:
409 	mutex_lock(&mut);
410 	idr_remove(&ctx_idr, ctx->id);
411 	mutex_unlock(&mut);
412 	kfree(ctx);
413 	return ret;
414 }
415 
416 static void ucma_cleanup_multicast(struct ucma_context *ctx)
417 {
418 	struct ucma_multicast *mc, *tmp;
419 
420 	mutex_lock(&mut);
421 	list_for_each_entry_safe(mc, tmp, &ctx->mc_list, list) {
422 		list_del(&mc->list);
423 		idr_remove(&multicast_idr, mc->id);
424 		kfree(mc);
425 	}
426 	mutex_unlock(&mut);
427 }
428 
429 static void ucma_cleanup_events(struct ucma_context *ctx)
430 {
431 	struct ucma_event *uevent, *tmp;
432 
433 	list_for_each_entry_safe(uevent, tmp, &ctx->file->event_list, list) {
434 		if (uevent->ctx != ctx)
435 			continue;
436 
437 		list_del(&uevent->list);
438 
439 		/* clear incoming connections. */
440 		if (uevent->resp.event == RDMA_CM_EVENT_CONNECT_REQUEST)
441 			rdma_destroy_id(uevent->cm_id);
442 
443 		kfree(uevent);
444 	}
445 }
446 
447 static void ucma_cleanup_mc_events(struct ucma_multicast *mc)
448 {
449 	struct ucma_event *uevent, *tmp;
450 
451 	list_for_each_entry_safe(uevent, tmp, &mc->ctx->file->event_list, list) {
452 		if (uevent->mc != mc)
453 			continue;
454 
455 		list_del(&uevent->list);
456 		kfree(uevent);
457 	}
458 }
459 
460 static int ucma_free_ctx(struct ucma_context *ctx)
461 {
462 	int events_reported;
463 
464 	/* No new events will be generated after destroying the id. */
465 	rdma_destroy_id(ctx->cm_id);
466 
467 	ucma_cleanup_multicast(ctx);
468 
469 	/* Cleanup events not yet reported to the user. */
470 	mutex_lock(&ctx->file->mut);
471 	ucma_cleanup_events(ctx);
472 	list_del(&ctx->list);
473 	mutex_unlock(&ctx->file->mut);
474 
475 	events_reported = ctx->events_reported;
476 	kfree(ctx);
477 	return events_reported;
478 }
479 
480 static ssize_t ucma_destroy_id(struct ucma_file *file, const char __user *inbuf,
481 			       int in_len, int out_len)
482 {
483 	struct rdma_ucm_destroy_id cmd;
484 	struct rdma_ucm_destroy_id_resp resp;
485 	struct ucma_context *ctx;
486 	int ret = 0;
487 
488 	if (out_len < sizeof(resp))
489 		return -ENOSPC;
490 
491 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
492 		return -EFAULT;
493 
494 	mutex_lock(&mut);
495 	ctx = _ucma_find_context(cmd.id, file);
496 	if (!IS_ERR(ctx))
497 		idr_remove(&ctx_idr, ctx->id);
498 	mutex_unlock(&mut);
499 
500 	if (IS_ERR(ctx))
501 		return PTR_ERR(ctx);
502 
503 	ucma_put_ctx(ctx);
504 	wait_for_completion(&ctx->comp);
505 	resp.events_reported = ucma_free_ctx(ctx);
506 
507 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
508 			 &resp, sizeof(resp)))
509 		ret = -EFAULT;
510 
511 	return ret;
512 }
513 
514 static ssize_t ucma_bind_addr(struct ucma_file *file, const char __user *inbuf,
515 			      int in_len, int out_len)
516 {
517 	struct rdma_ucm_bind_addr cmd;
518 	struct ucma_context *ctx;
519 	int ret;
520 
521 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
522 		return -EFAULT;
523 
524 	ctx = ucma_get_ctx(file, cmd.id);
525 	if (IS_ERR(ctx))
526 		return PTR_ERR(ctx);
527 
528 	ret = rdma_bind_addr(ctx->cm_id, (struct sockaddr *) &cmd.addr);
529 	ucma_put_ctx(ctx);
530 	return ret;
531 }
532 
533 static ssize_t ucma_resolve_addr(struct ucma_file *file,
534 				 const char __user *inbuf,
535 				 int in_len, int out_len)
536 {
537 	struct rdma_ucm_resolve_addr cmd;
538 	struct ucma_context *ctx;
539 	int ret;
540 
541 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
542 		return -EFAULT;
543 
544 	ctx = ucma_get_ctx(file, cmd.id);
545 	if (IS_ERR(ctx))
546 		return PTR_ERR(ctx);
547 
548 	ret = rdma_resolve_addr(ctx->cm_id, (struct sockaddr *) &cmd.src_addr,
549 				(struct sockaddr *) &cmd.dst_addr,
550 				cmd.timeout_ms);
551 	ucma_put_ctx(ctx);
552 	return ret;
553 }
554 
555 static ssize_t ucma_resolve_route(struct ucma_file *file,
556 				  const char __user *inbuf,
557 				  int in_len, int out_len)
558 {
559 	struct rdma_ucm_resolve_route cmd;
560 	struct ucma_context *ctx;
561 	int ret;
562 
563 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
564 		return -EFAULT;
565 
566 	ctx = ucma_get_ctx(file, cmd.id);
567 	if (IS_ERR(ctx))
568 		return PTR_ERR(ctx);
569 
570 	ret = rdma_resolve_route(ctx->cm_id, cmd.timeout_ms);
571 	ucma_put_ctx(ctx);
572 	return ret;
573 }
574 
575 static void ucma_copy_ib_route(struct rdma_ucm_query_route_resp *resp,
576 			       struct rdma_route *route)
577 {
578 	struct rdma_dev_addr *dev_addr;
579 
580 	resp->num_paths = route->num_paths;
581 	switch (route->num_paths) {
582 	case 0:
583 		dev_addr = &route->addr.dev_addr;
584 		rdma_addr_get_dgid(dev_addr,
585 				   (union ib_gid *) &resp->ib_route[0].dgid);
586 		rdma_addr_get_sgid(dev_addr,
587 				   (union ib_gid *) &resp->ib_route[0].sgid);
588 		resp->ib_route[0].pkey = cpu_to_be16(ib_addr_get_pkey(dev_addr));
589 		break;
590 	case 2:
591 		ib_copy_path_rec_to_user(&resp->ib_route[1],
592 					 &route->path_rec[1]);
593 		/* fall through */
594 	case 1:
595 		ib_copy_path_rec_to_user(&resp->ib_route[0],
596 					 &route->path_rec[0]);
597 		break;
598 	default:
599 		break;
600 	}
601 }
602 
603 static void ucma_copy_iboe_route(struct rdma_ucm_query_route_resp *resp,
604 				 struct rdma_route *route)
605 {
606 	struct rdma_dev_addr *dev_addr;
607 	struct net_device *dev;
608 	u16 vid = 0;
609 
610 	resp->num_paths = route->num_paths;
611 	switch (route->num_paths) {
612 	case 0:
613 		dev_addr = &route->addr.dev_addr;
614 		dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
615 			if (dev) {
616 				vid = rdma_vlan_dev_vlan_id(dev);
617 				dev_put(dev);
618 			}
619 
620 		iboe_mac_vlan_to_ll((union ib_gid *) &resp->ib_route[0].dgid,
621 				    dev_addr->dst_dev_addr, vid);
622 		iboe_addr_get_sgid(dev_addr,
623 				   (union ib_gid *) &resp->ib_route[0].sgid);
624 		resp->ib_route[0].pkey = cpu_to_be16(0xffff);
625 		break;
626 	case 2:
627 		ib_copy_path_rec_to_user(&resp->ib_route[1],
628 					 &route->path_rec[1]);
629 		/* fall through */
630 	case 1:
631 		ib_copy_path_rec_to_user(&resp->ib_route[0],
632 					 &route->path_rec[0]);
633 		break;
634 	default:
635 		break;
636 	}
637 }
638 
639 static void ucma_copy_iw_route(struct rdma_ucm_query_route_resp *resp,
640 			       struct rdma_route *route)
641 {
642 	struct rdma_dev_addr *dev_addr;
643 
644 	dev_addr = &route->addr.dev_addr;
645 	rdma_addr_get_dgid(dev_addr, (union ib_gid *) &resp->ib_route[0].dgid);
646 	rdma_addr_get_sgid(dev_addr, (union ib_gid *) &resp->ib_route[0].sgid);
647 }
648 
649 static ssize_t ucma_query_route(struct ucma_file *file,
650 				const char __user *inbuf,
651 				int in_len, int out_len)
652 {
653 	struct rdma_ucm_query_route cmd;
654 	struct rdma_ucm_query_route_resp resp;
655 	struct ucma_context *ctx;
656 	struct sockaddr *addr;
657 	int ret = 0;
658 
659 	if (out_len < sizeof(resp))
660 		return -ENOSPC;
661 
662 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
663 		return -EFAULT;
664 
665 	ctx = ucma_get_ctx(file, cmd.id);
666 	if (IS_ERR(ctx))
667 		return PTR_ERR(ctx);
668 
669 	memset(&resp, 0, sizeof resp);
670 	addr = (struct sockaddr *) &ctx->cm_id->route.addr.src_addr;
671 	memcpy(&resp.src_addr, addr, addr->sa_family == AF_INET ?
672 				     sizeof(struct sockaddr_in) :
673 				     sizeof(struct sockaddr_in6));
674 	addr = (struct sockaddr *) &ctx->cm_id->route.addr.dst_addr;
675 	memcpy(&resp.dst_addr, addr, addr->sa_family == AF_INET ?
676 				     sizeof(struct sockaddr_in) :
677 				     sizeof(struct sockaddr_in6));
678 	if (!ctx->cm_id->device)
679 		goto out;
680 
681 	resp.node_guid = (__force __u64) ctx->cm_id->device->node_guid;
682 	resp.port_num = ctx->cm_id->port_num;
683 	switch (rdma_node_get_transport(ctx->cm_id->device->node_type)) {
684 	case RDMA_TRANSPORT_IB:
685 		switch (rdma_port_get_link_layer(ctx->cm_id->device,
686 			ctx->cm_id->port_num)) {
687 		case IB_LINK_LAYER_INFINIBAND:
688 			ucma_copy_ib_route(&resp, &ctx->cm_id->route);
689 			break;
690 		case IB_LINK_LAYER_ETHERNET:
691 			ucma_copy_iboe_route(&resp, &ctx->cm_id->route);
692 			break;
693 		default:
694 			break;
695 		}
696 		break;
697 	case RDMA_TRANSPORT_IWARP:
698 		ucma_copy_iw_route(&resp, &ctx->cm_id->route);
699 		break;
700 	default:
701 		break;
702 	}
703 
704 out:
705 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
706 			 &resp, sizeof(resp)))
707 		ret = -EFAULT;
708 
709 	ucma_put_ctx(ctx);
710 	return ret;
711 }
712 
713 static void ucma_copy_conn_param(struct rdma_conn_param *dst,
714 				 struct rdma_ucm_conn_param *src)
715 {
716 	dst->private_data = src->private_data;
717 	dst->private_data_len = src->private_data_len;
718 	dst->responder_resources =src->responder_resources;
719 	dst->initiator_depth = src->initiator_depth;
720 	dst->flow_control = src->flow_control;
721 	dst->retry_count = src->retry_count;
722 	dst->rnr_retry_count = src->rnr_retry_count;
723 	dst->srq = src->srq;
724 	dst->qp_num = src->qp_num;
725 }
726 
727 static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf,
728 			    int in_len, int out_len)
729 {
730 	struct rdma_ucm_connect cmd;
731 	struct rdma_conn_param conn_param;
732 	struct ucma_context *ctx;
733 	int ret;
734 
735 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
736 		return -EFAULT;
737 
738 	if (!cmd.conn_param.valid)
739 		return -EINVAL;
740 
741 	ctx = ucma_get_ctx(file, cmd.id);
742 	if (IS_ERR(ctx))
743 		return PTR_ERR(ctx);
744 
745 	ucma_copy_conn_param(&conn_param, &cmd.conn_param);
746 	ret = rdma_connect(ctx->cm_id, &conn_param);
747 	ucma_put_ctx(ctx);
748 	return ret;
749 }
750 
751 static ssize_t ucma_listen(struct ucma_file *file, const char __user *inbuf,
752 			   int in_len, int out_len)
753 {
754 	struct rdma_ucm_listen cmd;
755 	struct ucma_context *ctx;
756 	int ret;
757 
758 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
759 		return -EFAULT;
760 
761 	ctx = ucma_get_ctx(file, cmd.id);
762 	if (IS_ERR(ctx))
763 		return PTR_ERR(ctx);
764 
765 	ctx->backlog = cmd.backlog > 0 && cmd.backlog < max_backlog ?
766 		       cmd.backlog : max_backlog;
767 	ret = rdma_listen(ctx->cm_id, ctx->backlog);
768 	ucma_put_ctx(ctx);
769 	return ret;
770 }
771 
772 static ssize_t ucma_accept(struct ucma_file *file, const char __user *inbuf,
773 			   int in_len, int out_len)
774 {
775 	struct rdma_ucm_accept cmd;
776 	struct rdma_conn_param conn_param;
777 	struct ucma_context *ctx;
778 	int ret;
779 
780 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
781 		return -EFAULT;
782 
783 	ctx = ucma_get_ctx(file, cmd.id);
784 	if (IS_ERR(ctx))
785 		return PTR_ERR(ctx);
786 
787 	if (cmd.conn_param.valid) {
788 		ctx->uid = cmd.uid;
789 		ucma_copy_conn_param(&conn_param, &cmd.conn_param);
790 		ret = rdma_accept(ctx->cm_id, &conn_param);
791 	} else
792 		ret = rdma_accept(ctx->cm_id, NULL);
793 
794 	ucma_put_ctx(ctx);
795 	return ret;
796 }
797 
798 static ssize_t ucma_reject(struct ucma_file *file, const char __user *inbuf,
799 			   int in_len, int out_len)
800 {
801 	struct rdma_ucm_reject cmd;
802 	struct ucma_context *ctx;
803 	int ret;
804 
805 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
806 		return -EFAULT;
807 
808 	ctx = ucma_get_ctx(file, cmd.id);
809 	if (IS_ERR(ctx))
810 		return PTR_ERR(ctx);
811 
812 	ret = rdma_reject(ctx->cm_id, cmd.private_data, cmd.private_data_len);
813 	ucma_put_ctx(ctx);
814 	return ret;
815 }
816 
817 static ssize_t ucma_disconnect(struct ucma_file *file, const char __user *inbuf,
818 			       int in_len, int out_len)
819 {
820 	struct rdma_ucm_disconnect 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_disconnect(ctx->cm_id);
832 	ucma_put_ctx(ctx);
833 	return ret;
834 }
835 
836 static ssize_t ucma_init_qp_attr(struct ucma_file *file,
837 				 const char __user *inbuf,
838 				 int in_len, int out_len)
839 {
840 	struct rdma_ucm_init_qp_attr cmd;
841 	struct ib_uverbs_qp_attr resp;
842 	struct ucma_context *ctx;
843 	struct ib_qp_attr qp_attr;
844 	int ret;
845 
846 	if (out_len < sizeof(resp))
847 		return -ENOSPC;
848 
849 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
850 		return -EFAULT;
851 
852 	ctx = ucma_get_ctx(file, cmd.id);
853 	if (IS_ERR(ctx))
854 		return PTR_ERR(ctx);
855 
856 	resp.qp_attr_mask = 0;
857 	memset(&qp_attr, 0, sizeof qp_attr);
858 	qp_attr.qp_state = cmd.qp_state;
859 	ret = rdma_init_qp_attr(ctx->cm_id, &qp_attr, &resp.qp_attr_mask);
860 	if (ret)
861 		goto out;
862 
863 	ib_copy_qp_attr_to_user(&resp, &qp_attr);
864 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
865 			 &resp, sizeof(resp)))
866 		ret = -EFAULT;
867 
868 out:
869 	ucma_put_ctx(ctx);
870 	return ret;
871 }
872 
873 static int ucma_set_option_id(struct ucma_context *ctx, int optname,
874 			      void *optval, size_t optlen)
875 {
876 	int ret = 0;
877 
878 	switch (optname) {
879 	case RDMA_OPTION_ID_TOS:
880 		if (optlen != sizeof(u8)) {
881 			ret = -EINVAL;
882 			break;
883 		}
884 		rdma_set_service_type(ctx->cm_id, *((u8 *) optval));
885 		break;
886 	default:
887 		ret = -ENOSYS;
888 	}
889 
890 	return ret;
891 }
892 
893 static int ucma_set_ib_path(struct ucma_context *ctx,
894 			    struct ib_path_rec_data *path_data, size_t optlen)
895 {
896 	struct ib_sa_path_rec sa_path;
897 	struct rdma_cm_event event;
898 	int ret;
899 
900 	if (optlen % sizeof(*path_data))
901 		return -EINVAL;
902 
903 	for (; optlen; optlen -= sizeof(*path_data), path_data++) {
904 		if (path_data->flags == (IB_PATH_GMP | IB_PATH_PRIMARY |
905 					 IB_PATH_BIDIRECTIONAL))
906 			break;
907 	}
908 
909 	if (!optlen)
910 		return -EINVAL;
911 
912 	ib_sa_unpack_path(path_data->path_rec, &sa_path);
913 	ret = rdma_set_ib_paths(ctx->cm_id, &sa_path, 1);
914 	if (ret)
915 		return ret;
916 
917 	memset(&event, 0, sizeof event);
918 	event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
919 	return ucma_event_handler(ctx->cm_id, &event);
920 }
921 
922 static int ucma_set_option_ib(struct ucma_context *ctx, int optname,
923 			      void *optval, size_t optlen)
924 {
925 	int ret;
926 
927 	switch (optname) {
928 	case RDMA_OPTION_IB_PATH:
929 		ret = ucma_set_ib_path(ctx, optval, optlen);
930 		break;
931 	default:
932 		ret = -ENOSYS;
933 	}
934 
935 	return ret;
936 }
937 
938 static int ucma_set_option_level(struct ucma_context *ctx, int level,
939 				 int optname, void *optval, size_t optlen)
940 {
941 	int ret;
942 
943 	switch (level) {
944 	case RDMA_OPTION_ID:
945 		ret = ucma_set_option_id(ctx, optname, optval, optlen);
946 		break;
947 	case RDMA_OPTION_IB:
948 		ret = ucma_set_option_ib(ctx, optname, optval, optlen);
949 		break;
950 	default:
951 		ret = -ENOSYS;
952 	}
953 
954 	return ret;
955 }
956 
957 static ssize_t ucma_set_option(struct ucma_file *file, const char __user *inbuf,
958 			       int in_len, int out_len)
959 {
960 	struct rdma_ucm_set_option cmd;
961 	struct ucma_context *ctx;
962 	void *optval;
963 	int ret;
964 
965 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
966 		return -EFAULT;
967 
968 	ctx = ucma_get_ctx(file, cmd.id);
969 	if (IS_ERR(ctx))
970 		return PTR_ERR(ctx);
971 
972 	optval = kmalloc(cmd.optlen, GFP_KERNEL);
973 	if (!optval) {
974 		ret = -ENOMEM;
975 		goto out1;
976 	}
977 
978 	if (copy_from_user(optval, (void __user *) (unsigned long) cmd.optval,
979 			   cmd.optlen)) {
980 		ret = -EFAULT;
981 		goto out2;
982 	}
983 
984 	ret = ucma_set_option_level(ctx, cmd.level, cmd.optname, optval,
985 				    cmd.optlen);
986 out2:
987 	kfree(optval);
988 out1:
989 	ucma_put_ctx(ctx);
990 	return ret;
991 }
992 
993 static ssize_t ucma_notify(struct ucma_file *file, const char __user *inbuf,
994 			   int in_len, int out_len)
995 {
996 	struct rdma_ucm_notify cmd;
997 	struct ucma_context *ctx;
998 	int ret;
999 
1000 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1001 		return -EFAULT;
1002 
1003 	ctx = ucma_get_ctx(file, cmd.id);
1004 	if (IS_ERR(ctx))
1005 		return PTR_ERR(ctx);
1006 
1007 	ret = rdma_notify(ctx->cm_id, (enum ib_event_type) cmd.event);
1008 	ucma_put_ctx(ctx);
1009 	return ret;
1010 }
1011 
1012 static ssize_t ucma_join_multicast(struct ucma_file *file,
1013 				   const char __user *inbuf,
1014 				   int in_len, int out_len)
1015 {
1016 	struct rdma_ucm_join_mcast cmd;
1017 	struct rdma_ucm_create_id_resp resp;
1018 	struct ucma_context *ctx;
1019 	struct ucma_multicast *mc;
1020 	int ret;
1021 
1022 	if (out_len < sizeof(resp))
1023 		return -ENOSPC;
1024 
1025 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1026 		return -EFAULT;
1027 
1028 	ctx = ucma_get_ctx(file, cmd.id);
1029 	if (IS_ERR(ctx))
1030 		return PTR_ERR(ctx);
1031 
1032 	mutex_lock(&file->mut);
1033 	mc = ucma_alloc_multicast(ctx);
1034 	if (!mc) {
1035 		ret = -ENOMEM;
1036 		goto err1;
1037 	}
1038 
1039 	mc->uid = cmd.uid;
1040 	memcpy(&mc->addr, &cmd.addr, sizeof cmd.addr);
1041 	ret = rdma_join_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr, mc);
1042 	if (ret)
1043 		goto err2;
1044 
1045 	resp.id = mc->id;
1046 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
1047 			 &resp, sizeof(resp))) {
1048 		ret = -EFAULT;
1049 		goto err3;
1050 	}
1051 
1052 	mutex_unlock(&file->mut);
1053 	ucma_put_ctx(ctx);
1054 	return 0;
1055 
1056 err3:
1057 	rdma_leave_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr);
1058 	ucma_cleanup_mc_events(mc);
1059 err2:
1060 	mutex_lock(&mut);
1061 	idr_remove(&multicast_idr, mc->id);
1062 	mutex_unlock(&mut);
1063 	list_del(&mc->list);
1064 	kfree(mc);
1065 err1:
1066 	mutex_unlock(&file->mut);
1067 	ucma_put_ctx(ctx);
1068 	return ret;
1069 }
1070 
1071 static ssize_t ucma_leave_multicast(struct ucma_file *file,
1072 				    const char __user *inbuf,
1073 				    int in_len, int out_len)
1074 {
1075 	struct rdma_ucm_destroy_id cmd;
1076 	struct rdma_ucm_destroy_id_resp resp;
1077 	struct ucma_multicast *mc;
1078 	int ret = 0;
1079 
1080 	if (out_len < sizeof(resp))
1081 		return -ENOSPC;
1082 
1083 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1084 		return -EFAULT;
1085 
1086 	mutex_lock(&mut);
1087 	mc = idr_find(&multicast_idr, cmd.id);
1088 	if (!mc)
1089 		mc = ERR_PTR(-ENOENT);
1090 	else if (mc->ctx->file != file)
1091 		mc = ERR_PTR(-EINVAL);
1092 	else {
1093 		idr_remove(&multicast_idr, mc->id);
1094 		atomic_inc(&mc->ctx->ref);
1095 	}
1096 	mutex_unlock(&mut);
1097 
1098 	if (IS_ERR(mc)) {
1099 		ret = PTR_ERR(mc);
1100 		goto out;
1101 	}
1102 
1103 	rdma_leave_multicast(mc->ctx->cm_id, (struct sockaddr *) &mc->addr);
1104 	mutex_lock(&mc->ctx->file->mut);
1105 	ucma_cleanup_mc_events(mc);
1106 	list_del(&mc->list);
1107 	mutex_unlock(&mc->ctx->file->mut);
1108 
1109 	ucma_put_ctx(mc->ctx);
1110 	resp.events_reported = mc->events_reported;
1111 	kfree(mc);
1112 
1113 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
1114 			 &resp, sizeof(resp)))
1115 		ret = -EFAULT;
1116 out:
1117 	return ret;
1118 }
1119 
1120 static void ucma_lock_files(struct ucma_file *file1, struct ucma_file *file2)
1121 {
1122 	/* Acquire mutex's based on pointer comparison to prevent deadlock. */
1123 	if (file1 < file2) {
1124 		mutex_lock(&file1->mut);
1125 		mutex_lock(&file2->mut);
1126 	} else {
1127 		mutex_lock(&file2->mut);
1128 		mutex_lock(&file1->mut);
1129 	}
1130 }
1131 
1132 static void ucma_unlock_files(struct ucma_file *file1, struct ucma_file *file2)
1133 {
1134 	if (file1 < file2) {
1135 		mutex_unlock(&file2->mut);
1136 		mutex_unlock(&file1->mut);
1137 	} else {
1138 		mutex_unlock(&file1->mut);
1139 		mutex_unlock(&file2->mut);
1140 	}
1141 }
1142 
1143 static void ucma_move_events(struct ucma_context *ctx, struct ucma_file *file)
1144 {
1145 	struct ucma_event *uevent, *tmp;
1146 
1147 	list_for_each_entry_safe(uevent, tmp, &ctx->file->event_list, list)
1148 		if (uevent->ctx == ctx)
1149 			list_move_tail(&uevent->list, &file->event_list);
1150 }
1151 
1152 static ssize_t ucma_migrate_id(struct ucma_file *new_file,
1153 			       const char __user *inbuf,
1154 			       int in_len, int out_len)
1155 {
1156 	struct rdma_ucm_migrate_id cmd;
1157 	struct rdma_ucm_migrate_resp resp;
1158 	struct ucma_context *ctx;
1159 	struct file *filp;
1160 	struct ucma_file *cur_file;
1161 	int ret = 0;
1162 
1163 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1164 		return -EFAULT;
1165 
1166 	/* Get current fd to protect against it being closed */
1167 	filp = fget(cmd.fd);
1168 	if (!filp)
1169 		return -ENOENT;
1170 
1171 	/* Validate current fd and prevent destruction of id. */
1172 	ctx = ucma_get_ctx(filp->private_data, cmd.id);
1173 	if (IS_ERR(ctx)) {
1174 		ret = PTR_ERR(ctx);
1175 		goto file_put;
1176 	}
1177 
1178 	cur_file = ctx->file;
1179 	if (cur_file == new_file) {
1180 		resp.events_reported = ctx->events_reported;
1181 		goto response;
1182 	}
1183 
1184 	/*
1185 	 * Migrate events between fd's, maintaining order, and avoiding new
1186 	 * events being added before existing events.
1187 	 */
1188 	ucma_lock_files(cur_file, new_file);
1189 	mutex_lock(&mut);
1190 
1191 	list_move_tail(&ctx->list, &new_file->ctx_list);
1192 	ucma_move_events(ctx, new_file);
1193 	ctx->file = new_file;
1194 	resp.events_reported = ctx->events_reported;
1195 
1196 	mutex_unlock(&mut);
1197 	ucma_unlock_files(cur_file, new_file);
1198 
1199 response:
1200 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
1201 			 &resp, sizeof(resp)))
1202 		ret = -EFAULT;
1203 
1204 	ucma_put_ctx(ctx);
1205 file_put:
1206 	fput(filp);
1207 	return ret;
1208 }
1209 
1210 static ssize_t (*ucma_cmd_table[])(struct ucma_file *file,
1211 				   const char __user *inbuf,
1212 				   int in_len, int out_len) = {
1213 	[RDMA_USER_CM_CMD_CREATE_ID]	= ucma_create_id,
1214 	[RDMA_USER_CM_CMD_DESTROY_ID]	= ucma_destroy_id,
1215 	[RDMA_USER_CM_CMD_BIND_ADDR]	= ucma_bind_addr,
1216 	[RDMA_USER_CM_CMD_RESOLVE_ADDR]	= ucma_resolve_addr,
1217 	[RDMA_USER_CM_CMD_RESOLVE_ROUTE]= ucma_resolve_route,
1218 	[RDMA_USER_CM_CMD_QUERY_ROUTE]	= ucma_query_route,
1219 	[RDMA_USER_CM_CMD_CONNECT]	= ucma_connect,
1220 	[RDMA_USER_CM_CMD_LISTEN]	= ucma_listen,
1221 	[RDMA_USER_CM_CMD_ACCEPT]	= ucma_accept,
1222 	[RDMA_USER_CM_CMD_REJECT]	= ucma_reject,
1223 	[RDMA_USER_CM_CMD_DISCONNECT]	= ucma_disconnect,
1224 	[RDMA_USER_CM_CMD_INIT_QP_ATTR]	= ucma_init_qp_attr,
1225 	[RDMA_USER_CM_CMD_GET_EVENT]	= ucma_get_event,
1226 	[RDMA_USER_CM_CMD_GET_OPTION]	= NULL,
1227 	[RDMA_USER_CM_CMD_SET_OPTION]	= ucma_set_option,
1228 	[RDMA_USER_CM_CMD_NOTIFY]	= ucma_notify,
1229 	[RDMA_USER_CM_CMD_JOIN_MCAST]	= ucma_join_multicast,
1230 	[RDMA_USER_CM_CMD_LEAVE_MCAST]	= ucma_leave_multicast,
1231 	[RDMA_USER_CM_CMD_MIGRATE_ID]	= ucma_migrate_id
1232 };
1233 
1234 static ssize_t ucma_write(struct file *filp, const char __user *buf,
1235 			  size_t len, loff_t *pos)
1236 {
1237 	struct ucma_file *file = filp->private_data;
1238 	struct rdma_ucm_cmd_hdr hdr;
1239 	ssize_t ret;
1240 
1241 	if (len < sizeof(hdr))
1242 		return -EINVAL;
1243 
1244 	if (copy_from_user(&hdr, buf, sizeof(hdr)))
1245 		return -EFAULT;
1246 
1247 	if (hdr.cmd < 0 || hdr.cmd >= ARRAY_SIZE(ucma_cmd_table))
1248 		return -EINVAL;
1249 
1250 	if (hdr.in + sizeof(hdr) > len)
1251 		return -EINVAL;
1252 
1253 	if (!ucma_cmd_table[hdr.cmd])
1254 		return -ENOSYS;
1255 
1256 	ret = ucma_cmd_table[hdr.cmd](file, buf + sizeof(hdr), hdr.in, hdr.out);
1257 	if (!ret)
1258 		ret = len;
1259 
1260 	return ret;
1261 }
1262 
1263 static unsigned int ucma_poll(struct file *filp, struct poll_table_struct *wait)
1264 {
1265 	struct ucma_file *file = filp->private_data;
1266 	unsigned int mask = 0;
1267 
1268 	poll_wait(filp, &file->poll_wait, wait);
1269 
1270 	if (!list_empty(&file->event_list))
1271 		mask = POLLIN | POLLRDNORM;
1272 
1273 	return mask;
1274 }
1275 
1276 /*
1277  * ucma_open() does not need the BKL:
1278  *
1279  *  - no global state is referred to;
1280  *  - there is no ioctl method to race against;
1281  *  - no further module initialization is required for open to work
1282  *    after the device is registered.
1283  */
1284 static int ucma_open(struct inode *inode, struct file *filp)
1285 {
1286 	struct ucma_file *file;
1287 
1288 	file = kmalloc(sizeof *file, GFP_KERNEL);
1289 	if (!file)
1290 		return -ENOMEM;
1291 
1292 	INIT_LIST_HEAD(&file->event_list);
1293 	INIT_LIST_HEAD(&file->ctx_list);
1294 	init_waitqueue_head(&file->poll_wait);
1295 	mutex_init(&file->mut);
1296 
1297 	filp->private_data = file;
1298 	file->filp = filp;
1299 
1300 	return nonseekable_open(inode, filp);
1301 }
1302 
1303 static int ucma_close(struct inode *inode, struct file *filp)
1304 {
1305 	struct ucma_file *file = filp->private_data;
1306 	struct ucma_context *ctx, *tmp;
1307 
1308 	mutex_lock(&file->mut);
1309 	list_for_each_entry_safe(ctx, tmp, &file->ctx_list, list) {
1310 		mutex_unlock(&file->mut);
1311 
1312 		mutex_lock(&mut);
1313 		idr_remove(&ctx_idr, ctx->id);
1314 		mutex_unlock(&mut);
1315 
1316 		ucma_free_ctx(ctx);
1317 		mutex_lock(&file->mut);
1318 	}
1319 	mutex_unlock(&file->mut);
1320 	kfree(file);
1321 	return 0;
1322 }
1323 
1324 static const struct file_operations ucma_fops = {
1325 	.owner 	 = THIS_MODULE,
1326 	.open 	 = ucma_open,
1327 	.release = ucma_close,
1328 	.write	 = ucma_write,
1329 	.poll    = ucma_poll,
1330 	.llseek	 = no_llseek,
1331 };
1332 
1333 static struct miscdevice ucma_misc = {
1334 	.minor	= MISC_DYNAMIC_MINOR,
1335 	.name	= "rdma_cm",
1336 	.fops	= &ucma_fops,
1337 };
1338 
1339 static ssize_t show_abi_version(struct device *dev,
1340 				struct device_attribute *attr,
1341 				char *buf)
1342 {
1343 	return sprintf(buf, "%d\n", RDMA_USER_CM_ABI_VERSION);
1344 }
1345 static DEVICE_ATTR(abi_version, S_IRUGO, show_abi_version, NULL);
1346 
1347 static int __init ucma_init(void)
1348 {
1349 	int ret;
1350 
1351 	ret = misc_register(&ucma_misc);
1352 	if (ret)
1353 		return ret;
1354 
1355 	ret = device_create_file(ucma_misc.this_device, &dev_attr_abi_version);
1356 	if (ret) {
1357 		printk(KERN_ERR "rdma_ucm: couldn't create abi_version attr\n");
1358 		goto err1;
1359 	}
1360 
1361 	ucma_ctl_table_hdr = register_sysctl_paths(ucma_ctl_path, ucma_ctl_table);
1362 	if (!ucma_ctl_table_hdr) {
1363 		printk(KERN_ERR "rdma_ucm: couldn't register sysctl paths\n");
1364 		ret = -ENOMEM;
1365 		goto err2;
1366 	}
1367 	return 0;
1368 err2:
1369 	device_remove_file(ucma_misc.this_device, &dev_attr_abi_version);
1370 err1:
1371 	misc_deregister(&ucma_misc);
1372 	return ret;
1373 }
1374 
1375 static void __exit ucma_cleanup(void)
1376 {
1377 	unregister_sysctl_table(ucma_ctl_table_hdr);
1378 	device_remove_file(ucma_misc.this_device, &dev_attr_abi_version);
1379 	misc_deregister(&ucma_misc);
1380 	idr_destroy(&ctx_idr);
1381 }
1382 
1383 module_init(ucma_init);
1384 module_exit(ucma_cleanup);
1385