1 /*
2  * Copyright (c) 2005 Topspin Communications.  All rights reserved.
3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
4  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
5  * Copyright (c) 2005 Voltaire, Inc. All rights reserved.
6  * Copyright (c) 2005 PathScale, Inc. All rights reserved.
7  *
8  * This software is available to you under a choice of one of two
9  * licenses.  You may choose to be licensed under the terms of the GNU
10  * General Public License (GPL) Version 2, available from the file
11  * COPYING in the main directory of this source tree, or the
12  * OpenIB.org BSD license below:
13  *
14  *     Redistribution and use in source and binary forms, with or
15  *     without modification, are permitted provided that the following
16  *     conditions are met:
17  *
18  *      - Redistributions of source code must retain the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer.
21  *
22  *      - Redistributions in binary form must reproduce the above
23  *        copyright notice, this list of conditions and the following
24  *        disclaimer in the documentation and/or other materials
25  *        provided with the distribution.
26  *
27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
28  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
29  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
30  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
31  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
32  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
33  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
34  * SOFTWARE.
35  */
36 
37 #include <linux/module.h>
38 #include <linux/init.h>
39 #include <linux/device.h>
40 #include <linux/err.h>
41 #include <linux/fs.h>
42 #include <linux/poll.h>
43 #include <linux/sched.h>
44 #include <linux/file.h>
45 #include <linux/cdev.h>
46 #include <linux/anon_inodes.h>
47 #include <linux/slab.h>
48 
49 #include <asm/uaccess.h>
50 
51 #include "uverbs.h"
52 
53 MODULE_AUTHOR("Roland Dreier");
54 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
55 MODULE_LICENSE("Dual BSD/GPL");
56 
57 enum {
58 	IB_UVERBS_MAJOR       = 231,
59 	IB_UVERBS_BASE_MINOR  = 192,
60 	IB_UVERBS_MAX_DEVICES = 32
61 };
62 
63 #define IB_UVERBS_BASE_DEV	MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
64 
65 static struct class *uverbs_class;
66 
67 DEFINE_SPINLOCK(ib_uverbs_idr_lock);
68 DEFINE_IDR(ib_uverbs_pd_idr);
69 DEFINE_IDR(ib_uverbs_mr_idr);
70 DEFINE_IDR(ib_uverbs_mw_idr);
71 DEFINE_IDR(ib_uverbs_ah_idr);
72 DEFINE_IDR(ib_uverbs_cq_idr);
73 DEFINE_IDR(ib_uverbs_qp_idr);
74 DEFINE_IDR(ib_uverbs_srq_idr);
75 DEFINE_IDR(ib_uverbs_xrcd_idr);
76 DEFINE_IDR(ib_uverbs_rule_idr);
77 
78 static DEFINE_SPINLOCK(map_lock);
79 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
80 
81 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
82 				     struct ib_device *ib_dev,
83 				     const char __user *buf, int in_len,
84 				     int out_len) = {
85 	[IB_USER_VERBS_CMD_GET_CONTEXT]		= ib_uverbs_get_context,
86 	[IB_USER_VERBS_CMD_QUERY_DEVICE]	= ib_uverbs_query_device,
87 	[IB_USER_VERBS_CMD_QUERY_PORT]		= ib_uverbs_query_port,
88 	[IB_USER_VERBS_CMD_ALLOC_PD]		= ib_uverbs_alloc_pd,
89 	[IB_USER_VERBS_CMD_DEALLOC_PD]		= ib_uverbs_dealloc_pd,
90 	[IB_USER_VERBS_CMD_REG_MR]		= ib_uverbs_reg_mr,
91 	[IB_USER_VERBS_CMD_REREG_MR]		= ib_uverbs_rereg_mr,
92 	[IB_USER_VERBS_CMD_DEREG_MR]		= ib_uverbs_dereg_mr,
93 	[IB_USER_VERBS_CMD_ALLOC_MW]		= ib_uverbs_alloc_mw,
94 	[IB_USER_VERBS_CMD_DEALLOC_MW]		= ib_uverbs_dealloc_mw,
95 	[IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
96 	[IB_USER_VERBS_CMD_CREATE_CQ]		= ib_uverbs_create_cq,
97 	[IB_USER_VERBS_CMD_RESIZE_CQ]		= ib_uverbs_resize_cq,
98 	[IB_USER_VERBS_CMD_POLL_CQ]		= ib_uverbs_poll_cq,
99 	[IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]	= ib_uverbs_req_notify_cq,
100 	[IB_USER_VERBS_CMD_DESTROY_CQ]		= ib_uverbs_destroy_cq,
101 	[IB_USER_VERBS_CMD_CREATE_QP]		= ib_uverbs_create_qp,
102 	[IB_USER_VERBS_CMD_QUERY_QP]		= ib_uverbs_query_qp,
103 	[IB_USER_VERBS_CMD_MODIFY_QP]		= ib_uverbs_modify_qp,
104 	[IB_USER_VERBS_CMD_DESTROY_QP]		= ib_uverbs_destroy_qp,
105 	[IB_USER_VERBS_CMD_POST_SEND]		= ib_uverbs_post_send,
106 	[IB_USER_VERBS_CMD_POST_RECV]		= ib_uverbs_post_recv,
107 	[IB_USER_VERBS_CMD_POST_SRQ_RECV]	= ib_uverbs_post_srq_recv,
108 	[IB_USER_VERBS_CMD_CREATE_AH]		= ib_uverbs_create_ah,
109 	[IB_USER_VERBS_CMD_DESTROY_AH]		= ib_uverbs_destroy_ah,
110 	[IB_USER_VERBS_CMD_ATTACH_MCAST]	= ib_uverbs_attach_mcast,
111 	[IB_USER_VERBS_CMD_DETACH_MCAST]	= ib_uverbs_detach_mcast,
112 	[IB_USER_VERBS_CMD_CREATE_SRQ]		= ib_uverbs_create_srq,
113 	[IB_USER_VERBS_CMD_MODIFY_SRQ]		= ib_uverbs_modify_srq,
114 	[IB_USER_VERBS_CMD_QUERY_SRQ]		= ib_uverbs_query_srq,
115 	[IB_USER_VERBS_CMD_DESTROY_SRQ]		= ib_uverbs_destroy_srq,
116 	[IB_USER_VERBS_CMD_OPEN_XRCD]		= ib_uverbs_open_xrcd,
117 	[IB_USER_VERBS_CMD_CLOSE_XRCD]		= ib_uverbs_close_xrcd,
118 	[IB_USER_VERBS_CMD_CREATE_XSRQ]		= ib_uverbs_create_xsrq,
119 	[IB_USER_VERBS_CMD_OPEN_QP]		= ib_uverbs_open_qp,
120 };
121 
122 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
123 				    struct ib_device *ib_dev,
124 				    struct ib_udata *ucore,
125 				    struct ib_udata *uhw) = {
126 	[IB_USER_VERBS_EX_CMD_CREATE_FLOW]	= ib_uverbs_ex_create_flow,
127 	[IB_USER_VERBS_EX_CMD_DESTROY_FLOW]	= ib_uverbs_ex_destroy_flow,
128 	[IB_USER_VERBS_EX_CMD_QUERY_DEVICE]	= ib_uverbs_ex_query_device,
129 	[IB_USER_VERBS_EX_CMD_CREATE_CQ]	= ib_uverbs_ex_create_cq,
130 	[IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
131 };
132 
133 static void ib_uverbs_add_one(struct ib_device *device);
134 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
135 
136 int uverbs_dealloc_mw(struct ib_mw *mw)
137 {
138 	struct ib_pd *pd = mw->pd;
139 	int ret;
140 
141 	ret = mw->device->dealloc_mw(mw);
142 	if (!ret)
143 		atomic_dec(&pd->usecnt);
144 	return ret;
145 }
146 
147 static void ib_uverbs_release_dev(struct kobject *kobj)
148 {
149 	struct ib_uverbs_device *dev =
150 		container_of(kobj, struct ib_uverbs_device, kobj);
151 
152 	cleanup_srcu_struct(&dev->disassociate_srcu);
153 	kfree(dev);
154 }
155 
156 static struct kobj_type ib_uverbs_dev_ktype = {
157 	.release = ib_uverbs_release_dev,
158 };
159 
160 static void ib_uverbs_release_event_file(struct kref *ref)
161 {
162 	struct ib_uverbs_event_file *file =
163 		container_of(ref, struct ib_uverbs_event_file, ref);
164 
165 	kfree(file);
166 }
167 
168 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
169 			  struct ib_uverbs_event_file *ev_file,
170 			  struct ib_ucq_object *uobj)
171 {
172 	struct ib_uverbs_event *evt, *tmp;
173 
174 	if (ev_file) {
175 		spin_lock_irq(&ev_file->lock);
176 		list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
177 			list_del(&evt->list);
178 			kfree(evt);
179 		}
180 		spin_unlock_irq(&ev_file->lock);
181 
182 		kref_put(&ev_file->ref, ib_uverbs_release_event_file);
183 	}
184 
185 	spin_lock_irq(&file->async_file->lock);
186 	list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
187 		list_del(&evt->list);
188 		kfree(evt);
189 	}
190 	spin_unlock_irq(&file->async_file->lock);
191 }
192 
193 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
194 			      struct ib_uevent_object *uobj)
195 {
196 	struct ib_uverbs_event *evt, *tmp;
197 
198 	spin_lock_irq(&file->async_file->lock);
199 	list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
200 		list_del(&evt->list);
201 		kfree(evt);
202 	}
203 	spin_unlock_irq(&file->async_file->lock);
204 }
205 
206 static void ib_uverbs_detach_umcast(struct ib_qp *qp,
207 				    struct ib_uqp_object *uobj)
208 {
209 	struct ib_uverbs_mcast_entry *mcast, *tmp;
210 
211 	list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
212 		ib_detach_mcast(qp, &mcast->gid, mcast->lid);
213 		list_del(&mcast->list);
214 		kfree(mcast);
215 	}
216 }
217 
218 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
219 				      struct ib_ucontext *context)
220 {
221 	struct ib_uobject *uobj, *tmp;
222 
223 	context->closing = 1;
224 
225 	list_for_each_entry_safe(uobj, tmp, &context->ah_list, list) {
226 		struct ib_ah *ah = uobj->object;
227 
228 		idr_remove_uobj(&ib_uverbs_ah_idr, uobj);
229 		ib_destroy_ah(ah);
230 		kfree(uobj);
231 	}
232 
233 	/* Remove MWs before QPs, in order to support type 2A MWs. */
234 	list_for_each_entry_safe(uobj, tmp, &context->mw_list, list) {
235 		struct ib_mw *mw = uobj->object;
236 
237 		idr_remove_uobj(&ib_uverbs_mw_idr, uobj);
238 		uverbs_dealloc_mw(mw);
239 		kfree(uobj);
240 	}
241 
242 	list_for_each_entry_safe(uobj, tmp, &context->rule_list, list) {
243 		struct ib_flow *flow_id = uobj->object;
244 
245 		idr_remove_uobj(&ib_uverbs_rule_idr, uobj);
246 		ib_destroy_flow(flow_id);
247 		kfree(uobj);
248 	}
249 
250 	list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {
251 		struct ib_qp *qp = uobj->object;
252 		struct ib_uqp_object *uqp =
253 			container_of(uobj, struct ib_uqp_object, uevent.uobject);
254 
255 		idr_remove_uobj(&ib_uverbs_qp_idr, uobj);
256 		if (qp != qp->real_qp) {
257 			ib_close_qp(qp);
258 		} else {
259 			ib_uverbs_detach_umcast(qp, uqp);
260 			ib_destroy_qp(qp);
261 		}
262 		ib_uverbs_release_uevent(file, &uqp->uevent);
263 		kfree(uqp);
264 	}
265 
266 	list_for_each_entry_safe(uobj, tmp, &context->srq_list, list) {
267 		struct ib_srq *srq = uobj->object;
268 		struct ib_uevent_object *uevent =
269 			container_of(uobj, struct ib_uevent_object, uobject);
270 
271 		idr_remove_uobj(&ib_uverbs_srq_idr, uobj);
272 		ib_destroy_srq(srq);
273 		ib_uverbs_release_uevent(file, uevent);
274 		kfree(uevent);
275 	}
276 
277 	list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {
278 		struct ib_cq *cq = uobj->object;
279 		struct ib_uverbs_event_file *ev_file = cq->cq_context;
280 		struct ib_ucq_object *ucq =
281 			container_of(uobj, struct ib_ucq_object, uobject);
282 
283 		idr_remove_uobj(&ib_uverbs_cq_idr, uobj);
284 		ib_destroy_cq(cq);
285 		ib_uverbs_release_ucq(file, ev_file, ucq);
286 		kfree(ucq);
287 	}
288 
289 	list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {
290 		struct ib_mr *mr = uobj->object;
291 
292 		idr_remove_uobj(&ib_uverbs_mr_idr, uobj);
293 		ib_dereg_mr(mr);
294 		kfree(uobj);
295 	}
296 
297 	mutex_lock(&file->device->xrcd_tree_mutex);
298 	list_for_each_entry_safe(uobj, tmp, &context->xrcd_list, list) {
299 		struct ib_xrcd *xrcd = uobj->object;
300 		struct ib_uxrcd_object *uxrcd =
301 			container_of(uobj, struct ib_uxrcd_object, uobject);
302 
303 		idr_remove_uobj(&ib_uverbs_xrcd_idr, uobj);
304 		ib_uverbs_dealloc_xrcd(file->device, xrcd);
305 		kfree(uxrcd);
306 	}
307 	mutex_unlock(&file->device->xrcd_tree_mutex);
308 
309 	list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
310 		struct ib_pd *pd = uobj->object;
311 
312 		idr_remove_uobj(&ib_uverbs_pd_idr, uobj);
313 		ib_dealloc_pd(pd);
314 		kfree(uobj);
315 	}
316 
317 	put_pid(context->tgid);
318 
319 	return context->device->dealloc_ucontext(context);
320 }
321 
322 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
323 {
324 	complete(&dev->comp);
325 }
326 
327 static void ib_uverbs_release_file(struct kref *ref)
328 {
329 	struct ib_uverbs_file *file =
330 		container_of(ref, struct ib_uverbs_file, ref);
331 	struct ib_device *ib_dev;
332 	int srcu_key;
333 
334 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
335 	ib_dev = srcu_dereference(file->device->ib_dev,
336 				  &file->device->disassociate_srcu);
337 	if (ib_dev && !ib_dev->disassociate_ucontext)
338 		module_put(ib_dev->owner);
339 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
340 
341 	if (atomic_dec_and_test(&file->device->refcount))
342 		ib_uverbs_comp_dev(file->device);
343 
344 	kfree(file);
345 }
346 
347 static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,
348 				    size_t count, loff_t *pos)
349 {
350 	struct ib_uverbs_event_file *file = filp->private_data;
351 	struct ib_uverbs_event *event;
352 	int eventsz;
353 	int ret = 0;
354 
355 	spin_lock_irq(&file->lock);
356 
357 	while (list_empty(&file->event_list)) {
358 		spin_unlock_irq(&file->lock);
359 
360 		if (filp->f_flags & O_NONBLOCK)
361 			return -EAGAIN;
362 
363 		if (wait_event_interruptible(file->poll_wait,
364 					     (!list_empty(&file->event_list) ||
365 			/* The barriers built into wait_event_interruptible()
366 			 * and wake_up() guarentee this will see the null set
367 			 * without using RCU
368 			 */
369 					     !file->uverbs_file->device->ib_dev)))
370 			return -ERESTARTSYS;
371 
372 		/* If device was disassociated and no event exists set an error */
373 		if (list_empty(&file->event_list) &&
374 		    !file->uverbs_file->device->ib_dev)
375 			return -EIO;
376 
377 		spin_lock_irq(&file->lock);
378 	}
379 
380 	event = list_entry(file->event_list.next, struct ib_uverbs_event, list);
381 
382 	if (file->is_async)
383 		eventsz = sizeof (struct ib_uverbs_async_event_desc);
384 	else
385 		eventsz = sizeof (struct ib_uverbs_comp_event_desc);
386 
387 	if (eventsz > count) {
388 		ret   = -EINVAL;
389 		event = NULL;
390 	} else {
391 		list_del(file->event_list.next);
392 		if (event->counter) {
393 			++(*event->counter);
394 			list_del(&event->obj_list);
395 		}
396 	}
397 
398 	spin_unlock_irq(&file->lock);
399 
400 	if (event) {
401 		if (copy_to_user(buf, event, eventsz))
402 			ret = -EFAULT;
403 		else
404 			ret = eventsz;
405 	}
406 
407 	kfree(event);
408 
409 	return ret;
410 }
411 
412 static unsigned int ib_uverbs_event_poll(struct file *filp,
413 					 struct poll_table_struct *wait)
414 {
415 	unsigned int pollflags = 0;
416 	struct ib_uverbs_event_file *file = filp->private_data;
417 
418 	poll_wait(filp, &file->poll_wait, wait);
419 
420 	spin_lock_irq(&file->lock);
421 	if (!list_empty(&file->event_list))
422 		pollflags = POLLIN | POLLRDNORM;
423 	spin_unlock_irq(&file->lock);
424 
425 	return pollflags;
426 }
427 
428 static int ib_uverbs_event_fasync(int fd, struct file *filp, int on)
429 {
430 	struct ib_uverbs_event_file *file = filp->private_data;
431 
432 	return fasync_helper(fd, filp, on, &file->async_queue);
433 }
434 
435 static int ib_uverbs_event_close(struct inode *inode, struct file *filp)
436 {
437 	struct ib_uverbs_event_file *file = filp->private_data;
438 	struct ib_uverbs_event *entry, *tmp;
439 	int closed_already = 0;
440 
441 	mutex_lock(&file->uverbs_file->device->lists_mutex);
442 	spin_lock_irq(&file->lock);
443 	closed_already = file->is_closed;
444 	file->is_closed = 1;
445 	list_for_each_entry_safe(entry, tmp, &file->event_list, list) {
446 		if (entry->counter)
447 			list_del(&entry->obj_list);
448 		kfree(entry);
449 	}
450 	spin_unlock_irq(&file->lock);
451 	if (!closed_already) {
452 		list_del(&file->list);
453 		if (file->is_async)
454 			ib_unregister_event_handler(&file->uverbs_file->
455 				event_handler);
456 	}
457 	mutex_unlock(&file->uverbs_file->device->lists_mutex);
458 
459 	kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);
460 	kref_put(&file->ref, ib_uverbs_release_event_file);
461 
462 	return 0;
463 }
464 
465 static const struct file_operations uverbs_event_fops = {
466 	.owner	 = THIS_MODULE,
467 	.read	 = ib_uverbs_event_read,
468 	.poll    = ib_uverbs_event_poll,
469 	.release = ib_uverbs_event_close,
470 	.fasync  = ib_uverbs_event_fasync,
471 	.llseek	 = no_llseek,
472 };
473 
474 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
475 {
476 	struct ib_uverbs_event_file    *file = cq_context;
477 	struct ib_ucq_object	       *uobj;
478 	struct ib_uverbs_event	       *entry;
479 	unsigned long			flags;
480 
481 	if (!file)
482 		return;
483 
484 	spin_lock_irqsave(&file->lock, flags);
485 	if (file->is_closed) {
486 		spin_unlock_irqrestore(&file->lock, flags);
487 		return;
488 	}
489 
490 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
491 	if (!entry) {
492 		spin_unlock_irqrestore(&file->lock, flags);
493 		return;
494 	}
495 
496 	uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
497 
498 	entry->desc.comp.cq_handle = cq->uobject->user_handle;
499 	entry->counter		   = &uobj->comp_events_reported;
500 
501 	list_add_tail(&entry->list, &file->event_list);
502 	list_add_tail(&entry->obj_list, &uobj->comp_list);
503 	spin_unlock_irqrestore(&file->lock, flags);
504 
505 	wake_up_interruptible(&file->poll_wait);
506 	kill_fasync(&file->async_queue, SIGIO, POLL_IN);
507 }
508 
509 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
510 				    __u64 element, __u64 event,
511 				    struct list_head *obj_list,
512 				    u32 *counter)
513 {
514 	struct ib_uverbs_event *entry;
515 	unsigned long flags;
516 
517 	spin_lock_irqsave(&file->async_file->lock, flags);
518 	if (file->async_file->is_closed) {
519 		spin_unlock_irqrestore(&file->async_file->lock, flags);
520 		return;
521 	}
522 
523 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
524 	if (!entry) {
525 		spin_unlock_irqrestore(&file->async_file->lock, flags);
526 		return;
527 	}
528 
529 	entry->desc.async.element    = element;
530 	entry->desc.async.event_type = event;
531 	entry->desc.async.reserved   = 0;
532 	entry->counter               = counter;
533 
534 	list_add_tail(&entry->list, &file->async_file->event_list);
535 	if (obj_list)
536 		list_add_tail(&entry->obj_list, obj_list);
537 	spin_unlock_irqrestore(&file->async_file->lock, flags);
538 
539 	wake_up_interruptible(&file->async_file->poll_wait);
540 	kill_fasync(&file->async_file->async_queue, SIGIO, POLL_IN);
541 }
542 
543 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
544 {
545 	struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
546 						  struct ib_ucq_object, uobject);
547 
548 	ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
549 				event->event, &uobj->async_list,
550 				&uobj->async_events_reported);
551 }
552 
553 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
554 {
555 	struct ib_uevent_object *uobj;
556 
557 	/* for XRC target qp's, check that qp is live */
558 	if (!event->element.qp->uobject || !event->element.qp->uobject->live)
559 		return;
560 
561 	uobj = container_of(event->element.qp->uobject,
562 			    struct ib_uevent_object, uobject);
563 
564 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
565 				event->event, &uobj->event_list,
566 				&uobj->events_reported);
567 }
568 
569 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
570 {
571 	struct ib_uevent_object *uobj;
572 
573 	uobj = container_of(event->element.srq->uobject,
574 			    struct ib_uevent_object, uobject);
575 
576 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
577 				event->event, &uobj->event_list,
578 				&uobj->events_reported);
579 }
580 
581 void ib_uverbs_event_handler(struct ib_event_handler *handler,
582 			     struct ib_event *event)
583 {
584 	struct ib_uverbs_file *file =
585 		container_of(handler, struct ib_uverbs_file, event_handler);
586 
587 	ib_uverbs_async_handler(file, event->element.port_num, event->event,
588 				NULL, NULL);
589 }
590 
591 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
592 {
593 	kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
594 	file->async_file = NULL;
595 }
596 
597 struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
598 					struct ib_device	*ib_dev,
599 					int is_async)
600 {
601 	struct ib_uverbs_event_file *ev_file;
602 	struct file *filp;
603 	int ret;
604 
605 	ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
606 	if (!ev_file)
607 		return ERR_PTR(-ENOMEM);
608 
609 	kref_init(&ev_file->ref);
610 	spin_lock_init(&ev_file->lock);
611 	INIT_LIST_HEAD(&ev_file->event_list);
612 	init_waitqueue_head(&ev_file->poll_wait);
613 	ev_file->uverbs_file = uverbs_file;
614 	kref_get(&ev_file->uverbs_file->ref);
615 	ev_file->async_queue = NULL;
616 	ev_file->is_closed   = 0;
617 
618 	filp = anon_inode_getfile("[infinibandevent]", &uverbs_event_fops,
619 				  ev_file, O_RDONLY);
620 	if (IS_ERR(filp))
621 		goto err_put_refs;
622 
623 	mutex_lock(&uverbs_file->device->lists_mutex);
624 	list_add_tail(&ev_file->list,
625 		      &uverbs_file->device->uverbs_events_file_list);
626 	mutex_unlock(&uverbs_file->device->lists_mutex);
627 
628 	if (is_async) {
629 		WARN_ON(uverbs_file->async_file);
630 		uverbs_file->async_file = ev_file;
631 		kref_get(&uverbs_file->async_file->ref);
632 		INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
633 				      ib_dev,
634 				      ib_uverbs_event_handler);
635 		ret = ib_register_event_handler(&uverbs_file->event_handler);
636 		if (ret)
637 			goto err_put_file;
638 
639 		/* At that point async file stuff was fully set */
640 		ev_file->is_async = 1;
641 	}
642 
643 	return filp;
644 
645 err_put_file:
646 	fput(filp);
647 	kref_put(&uverbs_file->async_file->ref, ib_uverbs_release_event_file);
648 	uverbs_file->async_file = NULL;
649 	return ERR_PTR(ret);
650 
651 err_put_refs:
652 	kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
653 	kref_put(&ev_file->ref, ib_uverbs_release_event_file);
654 	return filp;
655 }
656 
657 /*
658  * Look up a completion event file by FD.  If lookup is successful,
659  * takes a ref to the event file struct that it returns; if
660  * unsuccessful, returns NULL.
661  */
662 struct ib_uverbs_event_file *ib_uverbs_lookup_comp_file(int fd)
663 {
664 	struct ib_uverbs_event_file *ev_file = NULL;
665 	struct fd f = fdget(fd);
666 
667 	if (!f.file)
668 		return NULL;
669 
670 	if (f.file->f_op != &uverbs_event_fops)
671 		goto out;
672 
673 	ev_file = f.file->private_data;
674 	if (ev_file->is_async) {
675 		ev_file = NULL;
676 		goto out;
677 	}
678 
679 	kref_get(&ev_file->ref);
680 
681 out:
682 	fdput(f);
683 	return ev_file;
684 }
685 
686 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
687 			     size_t count, loff_t *pos)
688 {
689 	struct ib_uverbs_file *file = filp->private_data;
690 	struct ib_device *ib_dev;
691 	struct ib_uverbs_cmd_hdr hdr;
692 	__u32 flags;
693 	int srcu_key;
694 	ssize_t ret;
695 
696 	if (count < sizeof hdr)
697 		return -EINVAL;
698 
699 	if (copy_from_user(&hdr, buf, sizeof hdr))
700 		return -EFAULT;
701 
702 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
703 	ib_dev = srcu_dereference(file->device->ib_dev,
704 				  &file->device->disassociate_srcu);
705 	if (!ib_dev) {
706 		ret = -EIO;
707 		goto out;
708 	}
709 
710 	flags = (hdr.command &
711 		 IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
712 
713 	if (!flags) {
714 		__u32 command;
715 
716 		if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
717 					   IB_USER_VERBS_CMD_COMMAND_MASK)) {
718 			ret = -EINVAL;
719 			goto out;
720 		}
721 
722 		command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
723 
724 		if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
725 		    !uverbs_cmd_table[command]) {
726 			ret = -EINVAL;
727 			goto out;
728 		}
729 
730 		if (!file->ucontext &&
731 		    command != IB_USER_VERBS_CMD_GET_CONTEXT) {
732 			ret = -EINVAL;
733 			goto out;
734 		}
735 
736 		if (!(ib_dev->uverbs_cmd_mask & (1ull << command))) {
737 			ret = -ENOSYS;
738 			goto out;
739 		}
740 
741 		if (hdr.in_words * 4 != count) {
742 			ret = -EINVAL;
743 			goto out;
744 		}
745 
746 		ret = uverbs_cmd_table[command](file, ib_dev,
747 						 buf + sizeof(hdr),
748 						 hdr.in_words * 4,
749 						 hdr.out_words * 4);
750 
751 	} else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
752 		__u32 command;
753 
754 		struct ib_uverbs_ex_cmd_hdr ex_hdr;
755 		struct ib_udata ucore;
756 		struct ib_udata uhw;
757 		size_t written_count = count;
758 
759 		if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
760 					   IB_USER_VERBS_CMD_COMMAND_MASK)) {
761 			ret = -EINVAL;
762 			goto out;
763 		}
764 
765 		command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
766 
767 		if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
768 		    !uverbs_ex_cmd_table[command]) {
769 			ret = -ENOSYS;
770 			goto out;
771 		}
772 
773 		if (!file->ucontext) {
774 			ret = -EINVAL;
775 			goto out;
776 		}
777 
778 		if (!(ib_dev->uverbs_ex_cmd_mask & (1ull << command))) {
779 			ret = -ENOSYS;
780 			goto out;
781 		}
782 
783 		if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
784 			ret = -EINVAL;
785 			goto out;
786 		}
787 
788 		if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
789 			ret = -EFAULT;
790 			goto out;
791 		}
792 
793 		count -= sizeof(hdr) + sizeof(ex_hdr);
794 		buf += sizeof(hdr) + sizeof(ex_hdr);
795 
796 		if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
797 			ret = -EINVAL;
798 			goto out;
799 		}
800 
801 		if (ex_hdr.cmd_hdr_reserved) {
802 			ret = -EINVAL;
803 			goto out;
804 		}
805 
806 		if (ex_hdr.response) {
807 			if (!hdr.out_words && !ex_hdr.provider_out_words) {
808 				ret = -EINVAL;
809 				goto out;
810 			}
811 
812 			if (!access_ok(VERIFY_WRITE,
813 				       (void __user *) (unsigned long) ex_hdr.response,
814 				       (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
815 				ret = -EFAULT;
816 				goto out;
817 			}
818 		} else {
819 			if (hdr.out_words || ex_hdr.provider_out_words) {
820 				ret = -EINVAL;
821 				goto out;
822 			}
823 		}
824 
825 		INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
826 				       hdr.in_words * 8, hdr.out_words * 8);
827 
828 		INIT_UDATA_BUF_OR_NULL(&uhw,
829 				       buf + ucore.inlen,
830 				       (unsigned long) ex_hdr.response + ucore.outlen,
831 				       ex_hdr.provider_in_words * 8,
832 				       ex_hdr.provider_out_words * 8);
833 
834 		ret = uverbs_ex_cmd_table[command](file,
835 						   ib_dev,
836 						   &ucore,
837 						   &uhw);
838 		if (!ret)
839 			ret = written_count;
840 	} else {
841 		ret = -ENOSYS;
842 	}
843 
844 out:
845 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
846 	return ret;
847 }
848 
849 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
850 {
851 	struct ib_uverbs_file *file = filp->private_data;
852 	struct ib_device *ib_dev;
853 	int ret = 0;
854 	int srcu_key;
855 
856 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
857 	ib_dev = srcu_dereference(file->device->ib_dev,
858 				  &file->device->disassociate_srcu);
859 	if (!ib_dev) {
860 		ret = -EIO;
861 		goto out;
862 	}
863 
864 	if (!file->ucontext)
865 		ret = -ENODEV;
866 	else
867 		ret = ib_dev->mmap(file->ucontext, vma);
868 out:
869 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
870 	return ret;
871 }
872 
873 /*
874  * ib_uverbs_open() does not need the BKL:
875  *
876  *  - the ib_uverbs_device structures are properly reference counted and
877  *    everything else is purely local to the file being created, so
878  *    races against other open calls are not a problem;
879  *  - there is no ioctl method to race against;
880  *  - the open method will either immediately run -ENXIO, or all
881  *    required initialization will be done.
882  */
883 static int ib_uverbs_open(struct inode *inode, struct file *filp)
884 {
885 	struct ib_uverbs_device *dev;
886 	struct ib_uverbs_file *file;
887 	struct ib_device *ib_dev;
888 	int ret;
889 	int module_dependent;
890 	int srcu_key;
891 
892 	dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
893 	if (!atomic_inc_not_zero(&dev->refcount))
894 		return -ENXIO;
895 
896 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
897 	mutex_lock(&dev->lists_mutex);
898 	ib_dev = srcu_dereference(dev->ib_dev,
899 				  &dev->disassociate_srcu);
900 	if (!ib_dev) {
901 		ret = -EIO;
902 		goto err;
903 	}
904 
905 	/* In case IB device supports disassociate ucontext, there is no hard
906 	 * dependency between uverbs device and its low level device.
907 	 */
908 	module_dependent = !(ib_dev->disassociate_ucontext);
909 
910 	if (module_dependent) {
911 		if (!try_module_get(ib_dev->owner)) {
912 			ret = -ENODEV;
913 			goto err;
914 		}
915 	}
916 
917 	file = kzalloc(sizeof(*file), GFP_KERNEL);
918 	if (!file) {
919 		ret = -ENOMEM;
920 		if (module_dependent)
921 			goto err_module;
922 
923 		goto err;
924 	}
925 
926 	file->device	 = dev;
927 	file->ucontext	 = NULL;
928 	file->async_file = NULL;
929 	kref_init(&file->ref);
930 	mutex_init(&file->mutex);
931 
932 	filp->private_data = file;
933 	kobject_get(&dev->kobj);
934 	list_add_tail(&file->list, &dev->uverbs_file_list);
935 	mutex_unlock(&dev->lists_mutex);
936 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
937 
938 	return nonseekable_open(inode, filp);
939 
940 err_module:
941 	module_put(ib_dev->owner);
942 
943 err:
944 	mutex_unlock(&dev->lists_mutex);
945 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
946 	if (atomic_dec_and_test(&dev->refcount))
947 		ib_uverbs_comp_dev(dev);
948 
949 	return ret;
950 }
951 
952 static int ib_uverbs_close(struct inode *inode, struct file *filp)
953 {
954 	struct ib_uverbs_file *file = filp->private_data;
955 	struct ib_uverbs_device *dev = file->device;
956 	struct ib_ucontext *ucontext = NULL;
957 
958 	mutex_lock(&file->device->lists_mutex);
959 	ucontext = file->ucontext;
960 	file->ucontext = NULL;
961 	if (!file->is_closed) {
962 		list_del(&file->list);
963 		file->is_closed = 1;
964 	}
965 	mutex_unlock(&file->device->lists_mutex);
966 	if (ucontext)
967 		ib_uverbs_cleanup_ucontext(file, ucontext);
968 
969 	if (file->async_file)
970 		kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
971 
972 	kref_put(&file->ref, ib_uverbs_release_file);
973 	kobject_put(&dev->kobj);
974 
975 	return 0;
976 }
977 
978 static const struct file_operations uverbs_fops = {
979 	.owner	 = THIS_MODULE,
980 	.write	 = ib_uverbs_write,
981 	.open	 = ib_uverbs_open,
982 	.release = ib_uverbs_close,
983 	.llseek	 = no_llseek,
984 };
985 
986 static const struct file_operations uverbs_mmap_fops = {
987 	.owner	 = THIS_MODULE,
988 	.write	 = ib_uverbs_write,
989 	.mmap    = ib_uverbs_mmap,
990 	.open	 = ib_uverbs_open,
991 	.release = ib_uverbs_close,
992 	.llseek	 = no_llseek,
993 };
994 
995 static struct ib_client uverbs_client = {
996 	.name   = "uverbs",
997 	.add    = ib_uverbs_add_one,
998 	.remove = ib_uverbs_remove_one
999 };
1000 
1001 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
1002 			  char *buf)
1003 {
1004 	int ret = -ENODEV;
1005 	int srcu_key;
1006 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
1007 	struct ib_device *ib_dev;
1008 
1009 	if (!dev)
1010 		return -ENODEV;
1011 
1012 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1013 	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1014 	if (ib_dev)
1015 		ret = sprintf(buf, "%s\n", ib_dev->name);
1016 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1017 
1018 	return ret;
1019 }
1020 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1021 
1022 static ssize_t show_dev_abi_version(struct device *device,
1023 				    struct device_attribute *attr, char *buf)
1024 {
1025 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
1026 	int ret = -ENODEV;
1027 	int srcu_key;
1028 	struct ib_device *ib_dev;
1029 
1030 	if (!dev)
1031 		return -ENODEV;
1032 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1033 	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1034 	if (ib_dev)
1035 		ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1036 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1037 
1038 	return ret;
1039 }
1040 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1041 
1042 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1043 			 __stringify(IB_USER_VERBS_ABI_VERSION));
1044 
1045 static dev_t overflow_maj;
1046 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
1047 
1048 /*
1049  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
1050  * requesting a new major number and doubling the number of max devices we
1051  * support. It's stupid, but simple.
1052  */
1053 static int find_overflow_devnum(void)
1054 {
1055 	int ret;
1056 
1057 	if (!overflow_maj) {
1058 		ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
1059 					  "infiniband_verbs");
1060 		if (ret) {
1061 			printk(KERN_ERR "user_verbs: couldn't register dynamic device number\n");
1062 			return ret;
1063 		}
1064 	}
1065 
1066 	ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
1067 	if (ret >= IB_UVERBS_MAX_DEVICES)
1068 		return -1;
1069 
1070 	return ret;
1071 }
1072 
1073 static void ib_uverbs_add_one(struct ib_device *device)
1074 {
1075 	int devnum;
1076 	dev_t base;
1077 	struct ib_uverbs_device *uverbs_dev;
1078 	int ret;
1079 
1080 	if (!device->alloc_ucontext)
1081 		return;
1082 
1083 	uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1084 	if (!uverbs_dev)
1085 		return;
1086 
1087 	ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1088 	if (ret) {
1089 		kfree(uverbs_dev);
1090 		return;
1091 	}
1092 
1093 	atomic_set(&uverbs_dev->refcount, 1);
1094 	init_completion(&uverbs_dev->comp);
1095 	uverbs_dev->xrcd_tree = RB_ROOT;
1096 	mutex_init(&uverbs_dev->xrcd_tree_mutex);
1097 	kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1098 	mutex_init(&uverbs_dev->lists_mutex);
1099 	INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1100 	INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1101 
1102 	spin_lock(&map_lock);
1103 	devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1104 	if (devnum >= IB_UVERBS_MAX_DEVICES) {
1105 		spin_unlock(&map_lock);
1106 		devnum = find_overflow_devnum();
1107 		if (devnum < 0)
1108 			goto err;
1109 
1110 		spin_lock(&map_lock);
1111 		uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
1112 		base = devnum + overflow_maj;
1113 		set_bit(devnum, overflow_map);
1114 	} else {
1115 		uverbs_dev->devnum = devnum;
1116 		base = devnum + IB_UVERBS_BASE_DEV;
1117 		set_bit(devnum, dev_map);
1118 	}
1119 	spin_unlock(&map_lock);
1120 
1121 	rcu_assign_pointer(uverbs_dev->ib_dev, device);
1122 	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1123 
1124 	cdev_init(&uverbs_dev->cdev, NULL);
1125 	uverbs_dev->cdev.owner = THIS_MODULE;
1126 	uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1127 	uverbs_dev->cdev.kobj.parent = &uverbs_dev->kobj;
1128 	kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1129 	if (cdev_add(&uverbs_dev->cdev, base, 1))
1130 		goto err_cdev;
1131 
1132 	uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
1133 					uverbs_dev->cdev.dev, uverbs_dev,
1134 					"uverbs%d", uverbs_dev->devnum);
1135 	if (IS_ERR(uverbs_dev->dev))
1136 		goto err_cdev;
1137 
1138 	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1139 		goto err_class;
1140 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1141 		goto err_class;
1142 
1143 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
1144 
1145 	return;
1146 
1147 err_class:
1148 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1149 
1150 err_cdev:
1151 	cdev_del(&uverbs_dev->cdev);
1152 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1153 		clear_bit(devnum, dev_map);
1154 	else
1155 		clear_bit(devnum, overflow_map);
1156 
1157 err:
1158 	if (atomic_dec_and_test(&uverbs_dev->refcount))
1159 		ib_uverbs_comp_dev(uverbs_dev);
1160 	wait_for_completion(&uverbs_dev->comp);
1161 	kobject_put(&uverbs_dev->kobj);
1162 	return;
1163 }
1164 
1165 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1166 					struct ib_device *ib_dev)
1167 {
1168 	struct ib_uverbs_file *file;
1169 	struct ib_uverbs_event_file *event_file;
1170 	struct ib_event event;
1171 
1172 	/* Pending running commands to terminate */
1173 	synchronize_srcu(&uverbs_dev->disassociate_srcu);
1174 	event.event = IB_EVENT_DEVICE_FATAL;
1175 	event.element.port_num = 0;
1176 	event.device = ib_dev;
1177 
1178 	mutex_lock(&uverbs_dev->lists_mutex);
1179 	while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1180 		struct ib_ucontext *ucontext;
1181 
1182 		file = list_first_entry(&uverbs_dev->uverbs_file_list,
1183 					struct ib_uverbs_file, list);
1184 		file->is_closed = 1;
1185 		ucontext = file->ucontext;
1186 		list_del(&file->list);
1187 		file->ucontext = NULL;
1188 		kref_get(&file->ref);
1189 		mutex_unlock(&uverbs_dev->lists_mutex);
1190 		/* We must release the mutex before going ahead and calling
1191 		 * disassociate_ucontext. disassociate_ucontext might end up
1192 		 * indirectly calling uverbs_close, for example due to freeing
1193 		 * the resources (e.g mmput).
1194 		 */
1195 		ib_uverbs_event_handler(&file->event_handler, &event);
1196 		if (ucontext) {
1197 			ib_dev->disassociate_ucontext(ucontext);
1198 			ib_uverbs_cleanup_ucontext(file, ucontext);
1199 		}
1200 
1201 		mutex_lock(&uverbs_dev->lists_mutex);
1202 		kref_put(&file->ref, ib_uverbs_release_file);
1203 	}
1204 
1205 	while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1206 		event_file = list_first_entry(&uverbs_dev->
1207 					      uverbs_events_file_list,
1208 					      struct ib_uverbs_event_file,
1209 					      list);
1210 		spin_lock_irq(&event_file->lock);
1211 		event_file->is_closed = 1;
1212 		spin_unlock_irq(&event_file->lock);
1213 
1214 		list_del(&event_file->list);
1215 		if (event_file->is_async) {
1216 			ib_unregister_event_handler(&event_file->uverbs_file->
1217 						    event_handler);
1218 			event_file->uverbs_file->event_handler.device = NULL;
1219 		}
1220 
1221 		wake_up_interruptible(&event_file->poll_wait);
1222 		kill_fasync(&event_file->async_queue, SIGIO, POLL_IN);
1223 	}
1224 	mutex_unlock(&uverbs_dev->lists_mutex);
1225 }
1226 
1227 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1228 {
1229 	struct ib_uverbs_device *uverbs_dev = client_data;
1230 	int wait_clients = 1;
1231 
1232 	if (!uverbs_dev)
1233 		return;
1234 
1235 	dev_set_drvdata(uverbs_dev->dev, NULL);
1236 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1237 	cdev_del(&uverbs_dev->cdev);
1238 
1239 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1240 		clear_bit(uverbs_dev->devnum, dev_map);
1241 	else
1242 		clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
1243 
1244 	if (device->disassociate_ucontext) {
1245 		/* We disassociate HW resources and immediately return.
1246 		 * Userspace will see a EIO errno for all future access.
1247 		 * Upon returning, ib_device may be freed internally and is not
1248 		 * valid any more.
1249 		 * uverbs_device is still available until all clients close
1250 		 * their files, then the uverbs device ref count will be zero
1251 		 * and its resources will be freed.
1252 		 * Note: At this point no more files can be opened since the
1253 		 * cdev was deleted, however active clients can still issue
1254 		 * commands and close their open files.
1255 		 */
1256 		rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1257 		ib_uverbs_free_hw_resources(uverbs_dev, device);
1258 		wait_clients = 0;
1259 	}
1260 
1261 	if (atomic_dec_and_test(&uverbs_dev->refcount))
1262 		ib_uverbs_comp_dev(uverbs_dev);
1263 	if (wait_clients)
1264 		wait_for_completion(&uverbs_dev->comp);
1265 	kobject_put(&uverbs_dev->kobj);
1266 }
1267 
1268 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1269 {
1270 	if (mode)
1271 		*mode = 0666;
1272 	return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1273 }
1274 
1275 static int __init ib_uverbs_init(void)
1276 {
1277 	int ret;
1278 
1279 	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
1280 				     "infiniband_verbs");
1281 	if (ret) {
1282 		printk(KERN_ERR "user_verbs: couldn't register device number\n");
1283 		goto out;
1284 	}
1285 
1286 	uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1287 	if (IS_ERR(uverbs_class)) {
1288 		ret = PTR_ERR(uverbs_class);
1289 		printk(KERN_ERR "user_verbs: couldn't create class infiniband_verbs\n");
1290 		goto out_chrdev;
1291 	}
1292 
1293 	uverbs_class->devnode = uverbs_devnode;
1294 
1295 	ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1296 	if (ret) {
1297 		printk(KERN_ERR "user_verbs: couldn't create abi_version attribute\n");
1298 		goto out_class;
1299 	}
1300 
1301 	ret = ib_register_client(&uverbs_client);
1302 	if (ret) {
1303 		printk(KERN_ERR "user_verbs: couldn't register client\n");
1304 		goto out_class;
1305 	}
1306 
1307 	return 0;
1308 
1309 out_class:
1310 	class_destroy(uverbs_class);
1311 
1312 out_chrdev:
1313 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1314 
1315 out:
1316 	return ret;
1317 }
1318 
1319 static void __exit ib_uverbs_cleanup(void)
1320 {
1321 	ib_unregister_client(&uverbs_client);
1322 	class_destroy(uverbs_class);
1323 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1324 	if (overflow_maj)
1325 		unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1326 	idr_destroy(&ib_uverbs_pd_idr);
1327 	idr_destroy(&ib_uverbs_mr_idr);
1328 	idr_destroy(&ib_uverbs_mw_idr);
1329 	idr_destroy(&ib_uverbs_ah_idr);
1330 	idr_destroy(&ib_uverbs_cq_idr);
1331 	idr_destroy(&ib_uverbs_qp_idr);
1332 	idr_destroy(&ib_uverbs_srq_idr);
1333 }
1334 
1335 module_init(ib_uverbs_init);
1336 module_exit(ib_uverbs_cleanup);
1337