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 <linux/uaccess.h>
50 
51 #include <rdma/ib.h>
52 
53 #include "uverbs.h"
54 #include "core_priv.h"
55 #include "rdma_core.h"
56 
57 MODULE_AUTHOR("Roland Dreier");
58 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
59 MODULE_LICENSE("Dual BSD/GPL");
60 
61 enum {
62 	IB_UVERBS_MAJOR       = 231,
63 	IB_UVERBS_BASE_MINOR  = 192,
64 	IB_UVERBS_MAX_DEVICES = 32
65 };
66 
67 #define IB_UVERBS_BASE_DEV	MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
68 
69 static struct class *uverbs_class;
70 
71 static DEFINE_SPINLOCK(map_lock);
72 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
73 
74 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
75 				     struct ib_device *ib_dev,
76 				     const char __user *buf, int in_len,
77 				     int out_len) = {
78 	[IB_USER_VERBS_CMD_GET_CONTEXT]		= ib_uverbs_get_context,
79 	[IB_USER_VERBS_CMD_QUERY_DEVICE]	= ib_uverbs_query_device,
80 	[IB_USER_VERBS_CMD_QUERY_PORT]		= ib_uverbs_query_port,
81 	[IB_USER_VERBS_CMD_ALLOC_PD]		= ib_uverbs_alloc_pd,
82 	[IB_USER_VERBS_CMD_DEALLOC_PD]		= ib_uverbs_dealloc_pd,
83 	[IB_USER_VERBS_CMD_REG_MR]		= ib_uverbs_reg_mr,
84 	[IB_USER_VERBS_CMD_REREG_MR]		= ib_uverbs_rereg_mr,
85 	[IB_USER_VERBS_CMD_DEREG_MR]		= ib_uverbs_dereg_mr,
86 	[IB_USER_VERBS_CMD_ALLOC_MW]		= ib_uverbs_alloc_mw,
87 	[IB_USER_VERBS_CMD_DEALLOC_MW]		= ib_uverbs_dealloc_mw,
88 	[IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
89 	[IB_USER_VERBS_CMD_CREATE_CQ]		= ib_uverbs_create_cq,
90 	[IB_USER_VERBS_CMD_RESIZE_CQ]		= ib_uverbs_resize_cq,
91 	[IB_USER_VERBS_CMD_POLL_CQ]		= ib_uverbs_poll_cq,
92 	[IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]	= ib_uverbs_req_notify_cq,
93 	[IB_USER_VERBS_CMD_DESTROY_CQ]		= ib_uverbs_destroy_cq,
94 	[IB_USER_VERBS_CMD_CREATE_QP]		= ib_uverbs_create_qp,
95 	[IB_USER_VERBS_CMD_QUERY_QP]		= ib_uverbs_query_qp,
96 	[IB_USER_VERBS_CMD_MODIFY_QP]		= ib_uverbs_modify_qp,
97 	[IB_USER_VERBS_CMD_DESTROY_QP]		= ib_uverbs_destroy_qp,
98 	[IB_USER_VERBS_CMD_POST_SEND]		= ib_uverbs_post_send,
99 	[IB_USER_VERBS_CMD_POST_RECV]		= ib_uverbs_post_recv,
100 	[IB_USER_VERBS_CMD_POST_SRQ_RECV]	= ib_uverbs_post_srq_recv,
101 	[IB_USER_VERBS_CMD_CREATE_AH]		= ib_uverbs_create_ah,
102 	[IB_USER_VERBS_CMD_DESTROY_AH]		= ib_uverbs_destroy_ah,
103 	[IB_USER_VERBS_CMD_ATTACH_MCAST]	= ib_uverbs_attach_mcast,
104 	[IB_USER_VERBS_CMD_DETACH_MCAST]	= ib_uverbs_detach_mcast,
105 	[IB_USER_VERBS_CMD_CREATE_SRQ]		= ib_uverbs_create_srq,
106 	[IB_USER_VERBS_CMD_MODIFY_SRQ]		= ib_uverbs_modify_srq,
107 	[IB_USER_VERBS_CMD_QUERY_SRQ]		= ib_uverbs_query_srq,
108 	[IB_USER_VERBS_CMD_DESTROY_SRQ]		= ib_uverbs_destroy_srq,
109 	[IB_USER_VERBS_CMD_OPEN_XRCD]		= ib_uverbs_open_xrcd,
110 	[IB_USER_VERBS_CMD_CLOSE_XRCD]		= ib_uverbs_close_xrcd,
111 	[IB_USER_VERBS_CMD_CREATE_XSRQ]		= ib_uverbs_create_xsrq,
112 	[IB_USER_VERBS_CMD_OPEN_QP]		= ib_uverbs_open_qp,
113 };
114 
115 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
116 				    struct ib_device *ib_dev,
117 				    struct ib_udata *ucore,
118 				    struct ib_udata *uhw) = {
119 	[IB_USER_VERBS_EX_CMD_CREATE_FLOW]	= ib_uverbs_ex_create_flow,
120 	[IB_USER_VERBS_EX_CMD_DESTROY_FLOW]	= ib_uverbs_ex_destroy_flow,
121 	[IB_USER_VERBS_EX_CMD_QUERY_DEVICE]	= ib_uverbs_ex_query_device,
122 	[IB_USER_VERBS_EX_CMD_CREATE_CQ]	= ib_uverbs_ex_create_cq,
123 	[IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
124 	[IB_USER_VERBS_EX_CMD_CREATE_WQ]        = ib_uverbs_ex_create_wq,
125 	[IB_USER_VERBS_EX_CMD_MODIFY_WQ]        = ib_uverbs_ex_modify_wq,
126 	[IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
127 	[IB_USER_VERBS_EX_CMD_CREATE_RWQ_IND_TBL] = ib_uverbs_ex_create_rwq_ind_table,
128 	[IB_USER_VERBS_EX_CMD_DESTROY_RWQ_IND_TBL] = ib_uverbs_ex_destroy_rwq_ind_table,
129 	[IB_USER_VERBS_EX_CMD_MODIFY_QP]        = ib_uverbs_ex_modify_qp,
130 };
131 
132 static void ib_uverbs_add_one(struct ib_device *device);
133 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
134 
135 int uverbs_dealloc_mw(struct ib_mw *mw)
136 {
137 	struct ib_pd *pd = mw->pd;
138 	int ret;
139 
140 	ret = mw->device->dealloc_mw(mw);
141 	if (!ret)
142 		atomic_dec(&pd->usecnt);
143 	return ret;
144 }
145 
146 static void ib_uverbs_release_dev(struct kobject *kobj)
147 {
148 	struct ib_uverbs_device *dev =
149 		container_of(kobj, struct ib_uverbs_device, kobj);
150 
151 	cleanup_srcu_struct(&dev->disassociate_srcu);
152 	kfree(dev);
153 }
154 
155 static struct kobj_type ib_uverbs_dev_ktype = {
156 	.release = ib_uverbs_release_dev,
157 };
158 
159 static void ib_uverbs_release_async_event_file(struct kref *ref)
160 {
161 	struct ib_uverbs_async_event_file *file =
162 		container_of(ref, struct ib_uverbs_async_event_file, ref);
163 
164 	kfree(file);
165 }
166 
167 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
168 			  struct ib_uverbs_completion_event_file *ev_file,
169 			  struct ib_ucq_object *uobj)
170 {
171 	struct ib_uverbs_event *evt, *tmp;
172 
173 	if (ev_file) {
174 		spin_lock_irq(&ev_file->ev_queue.lock);
175 		list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
176 			list_del(&evt->list);
177 			kfree(evt);
178 		}
179 		spin_unlock_irq(&ev_file->ev_queue.lock);
180 
181 		uverbs_uobject_put(&ev_file->uobj_file.uobj);
182 	}
183 
184 	spin_lock_irq(&file->async_file->ev_queue.lock);
185 	list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
186 		list_del(&evt->list);
187 		kfree(evt);
188 	}
189 	spin_unlock_irq(&file->async_file->ev_queue.lock);
190 }
191 
192 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
193 			      struct ib_uevent_object *uobj)
194 {
195 	struct ib_uverbs_event *evt, *tmp;
196 
197 	spin_lock_irq(&file->async_file->ev_queue.lock);
198 	list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
199 		list_del(&evt->list);
200 		kfree(evt);
201 	}
202 	spin_unlock_irq(&file->async_file->ev_queue.lock);
203 }
204 
205 void ib_uverbs_detach_umcast(struct ib_qp *qp,
206 			     struct ib_uqp_object *uobj)
207 {
208 	struct ib_uverbs_mcast_entry *mcast, *tmp;
209 
210 	list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
211 		ib_detach_mcast(qp, &mcast->gid, mcast->lid);
212 		list_del(&mcast->list);
213 		kfree(mcast);
214 	}
215 }
216 
217 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
218 				      struct ib_ucontext *context,
219 				      bool device_removed)
220 {
221 	context->closing = 1;
222 	uverbs_cleanup_ucontext(context, device_removed);
223 	put_pid(context->tgid);
224 
225 	ib_rdmacg_uncharge(&context->cg_obj, context->device,
226 			   RDMACG_RESOURCE_HCA_HANDLE);
227 
228 	return context->device->dealloc_ucontext(context);
229 }
230 
231 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
232 {
233 	complete(&dev->comp);
234 }
235 
236 void ib_uverbs_release_file(struct kref *ref)
237 {
238 	struct ib_uverbs_file *file =
239 		container_of(ref, struct ib_uverbs_file, ref);
240 	struct ib_device *ib_dev;
241 	int srcu_key;
242 
243 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
244 	ib_dev = srcu_dereference(file->device->ib_dev,
245 				  &file->device->disassociate_srcu);
246 	if (ib_dev && !ib_dev->disassociate_ucontext)
247 		module_put(ib_dev->owner);
248 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
249 
250 	if (atomic_dec_and_test(&file->device->refcount))
251 		ib_uverbs_comp_dev(file->device);
252 
253 	kobject_put(&file->device->kobj);
254 	kfree(file);
255 }
256 
257 static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue,
258 				    struct ib_uverbs_file *uverbs_file,
259 				    struct file *filp, char __user *buf,
260 				    size_t count, loff_t *pos,
261 				    size_t eventsz)
262 {
263 	struct ib_uverbs_event *event;
264 	int ret = 0;
265 
266 	spin_lock_irq(&ev_queue->lock);
267 
268 	while (list_empty(&ev_queue->event_list)) {
269 		spin_unlock_irq(&ev_queue->lock);
270 
271 		if (filp->f_flags & O_NONBLOCK)
272 			return -EAGAIN;
273 
274 		if (wait_event_interruptible(ev_queue->poll_wait,
275 					     (!list_empty(&ev_queue->event_list) ||
276 			/* The barriers built into wait_event_interruptible()
277 			 * and wake_up() guarentee this will see the null set
278 			 * without using RCU
279 			 */
280 					     !uverbs_file->device->ib_dev)))
281 			return -ERESTARTSYS;
282 
283 		/* If device was disassociated and no event exists set an error */
284 		if (list_empty(&ev_queue->event_list) &&
285 		    !uverbs_file->device->ib_dev)
286 			return -EIO;
287 
288 		spin_lock_irq(&ev_queue->lock);
289 	}
290 
291 	event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list);
292 
293 	if (eventsz > count) {
294 		ret   = -EINVAL;
295 		event = NULL;
296 	} else {
297 		list_del(ev_queue->event_list.next);
298 		if (event->counter) {
299 			++(*event->counter);
300 			list_del(&event->obj_list);
301 		}
302 	}
303 
304 	spin_unlock_irq(&ev_queue->lock);
305 
306 	if (event) {
307 		if (copy_to_user(buf, event, eventsz))
308 			ret = -EFAULT;
309 		else
310 			ret = eventsz;
311 	}
312 
313 	kfree(event);
314 
315 	return ret;
316 }
317 
318 static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf,
319 					  size_t count, loff_t *pos)
320 {
321 	struct ib_uverbs_async_event_file *file = filp->private_data;
322 
323 	return ib_uverbs_event_read(&file->ev_queue, file->uverbs_file, filp,
324 				    buf, count, pos,
325 				    sizeof(struct ib_uverbs_async_event_desc));
326 }
327 
328 static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,
329 					 size_t count, loff_t *pos)
330 {
331 	struct ib_uverbs_completion_event_file *comp_ev_file =
332 		filp->private_data;
333 
334 	return ib_uverbs_event_read(&comp_ev_file->ev_queue,
335 				    comp_ev_file->uobj_file.ufile, filp,
336 				    buf, count, pos,
337 				    sizeof(struct ib_uverbs_comp_event_desc));
338 }
339 
340 static unsigned int ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
341 					 struct file *filp,
342 					 struct poll_table_struct *wait)
343 {
344 	unsigned int pollflags = 0;
345 
346 	poll_wait(filp, &ev_queue->poll_wait, wait);
347 
348 	spin_lock_irq(&ev_queue->lock);
349 	if (!list_empty(&ev_queue->event_list))
350 		pollflags = POLLIN | POLLRDNORM;
351 	spin_unlock_irq(&ev_queue->lock);
352 
353 	return pollflags;
354 }
355 
356 static unsigned int ib_uverbs_async_event_poll(struct file *filp,
357 					       struct poll_table_struct *wait)
358 {
359 	return ib_uverbs_event_poll(filp->private_data, filp, wait);
360 }
361 
362 static unsigned int ib_uverbs_comp_event_poll(struct file *filp,
363 					      struct poll_table_struct *wait)
364 {
365 	struct ib_uverbs_completion_event_file *comp_ev_file =
366 		filp->private_data;
367 
368 	return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait);
369 }
370 
371 static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on)
372 {
373 	struct ib_uverbs_event_queue *ev_queue = filp->private_data;
374 
375 	return fasync_helper(fd, filp, on, &ev_queue->async_queue);
376 }
377 
378 static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on)
379 {
380 	struct ib_uverbs_completion_event_file *comp_ev_file =
381 		filp->private_data;
382 
383 	return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue);
384 }
385 
386 static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
387 {
388 	struct ib_uverbs_async_event_file *file = filp->private_data;
389 	struct ib_uverbs_file *uverbs_file = file->uverbs_file;
390 	struct ib_uverbs_event *entry, *tmp;
391 	int closed_already = 0;
392 
393 	mutex_lock(&uverbs_file->device->lists_mutex);
394 	spin_lock_irq(&file->ev_queue.lock);
395 	closed_already = file->ev_queue.is_closed;
396 	file->ev_queue.is_closed = 1;
397 	list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
398 		if (entry->counter)
399 			list_del(&entry->obj_list);
400 		kfree(entry);
401 	}
402 	spin_unlock_irq(&file->ev_queue.lock);
403 	if (!closed_already) {
404 		list_del(&file->list);
405 		ib_unregister_event_handler(&uverbs_file->event_handler);
406 	}
407 	mutex_unlock(&uverbs_file->device->lists_mutex);
408 
409 	kref_put(&uverbs_file->ref, ib_uverbs_release_file);
410 	kref_put(&file->ref, ib_uverbs_release_async_event_file);
411 
412 	return 0;
413 }
414 
415 static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp)
416 {
417 	struct ib_uverbs_completion_event_file *file = filp->private_data;
418 	struct ib_uverbs_event *entry, *tmp;
419 
420 	spin_lock_irq(&file->ev_queue.lock);
421 	list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
422 		if (entry->counter)
423 			list_del(&entry->obj_list);
424 		kfree(entry);
425 	}
426 	spin_unlock_irq(&file->ev_queue.lock);
427 
428 	uverbs_close_fd(filp);
429 
430 	return 0;
431 }
432 
433 const struct file_operations uverbs_event_fops = {
434 	.owner	 = THIS_MODULE,
435 	.read	 = ib_uverbs_comp_event_read,
436 	.poll    = ib_uverbs_comp_event_poll,
437 	.release = ib_uverbs_comp_event_close,
438 	.fasync  = ib_uverbs_comp_event_fasync,
439 	.llseek	 = no_llseek,
440 };
441 
442 static const struct file_operations uverbs_async_event_fops = {
443 	.owner	 = THIS_MODULE,
444 	.read	 = ib_uverbs_async_event_read,
445 	.poll    = ib_uverbs_async_event_poll,
446 	.release = ib_uverbs_async_event_close,
447 	.fasync  = ib_uverbs_async_event_fasync,
448 	.llseek	 = no_llseek,
449 };
450 
451 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
452 {
453 	struct ib_uverbs_event_queue   *ev_queue = cq_context;
454 	struct ib_ucq_object	       *uobj;
455 	struct ib_uverbs_event	       *entry;
456 	unsigned long			flags;
457 
458 	if (!ev_queue)
459 		return;
460 
461 	spin_lock_irqsave(&ev_queue->lock, flags);
462 	if (ev_queue->is_closed) {
463 		spin_unlock_irqrestore(&ev_queue->lock, flags);
464 		return;
465 	}
466 
467 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
468 	if (!entry) {
469 		spin_unlock_irqrestore(&ev_queue->lock, flags);
470 		return;
471 	}
472 
473 	uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
474 
475 	entry->desc.comp.cq_handle = cq->uobject->user_handle;
476 	entry->counter		   = &uobj->comp_events_reported;
477 
478 	list_add_tail(&entry->list, &ev_queue->event_list);
479 	list_add_tail(&entry->obj_list, &uobj->comp_list);
480 	spin_unlock_irqrestore(&ev_queue->lock, flags);
481 
482 	wake_up_interruptible(&ev_queue->poll_wait);
483 	kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN);
484 }
485 
486 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
487 				    __u64 element, __u64 event,
488 				    struct list_head *obj_list,
489 				    u32 *counter)
490 {
491 	struct ib_uverbs_event *entry;
492 	unsigned long flags;
493 
494 	spin_lock_irqsave(&file->async_file->ev_queue.lock, flags);
495 	if (file->async_file->ev_queue.is_closed) {
496 		spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
497 		return;
498 	}
499 
500 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
501 	if (!entry) {
502 		spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
503 		return;
504 	}
505 
506 	entry->desc.async.element    = element;
507 	entry->desc.async.event_type = event;
508 	entry->desc.async.reserved   = 0;
509 	entry->counter               = counter;
510 
511 	list_add_tail(&entry->list, &file->async_file->ev_queue.event_list);
512 	if (obj_list)
513 		list_add_tail(&entry->obj_list, obj_list);
514 	spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
515 
516 	wake_up_interruptible(&file->async_file->ev_queue.poll_wait);
517 	kill_fasync(&file->async_file->ev_queue.async_queue, SIGIO, POLL_IN);
518 }
519 
520 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
521 {
522 	struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
523 						  struct ib_ucq_object, uobject);
524 
525 	ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
526 				event->event, &uobj->async_list,
527 				&uobj->async_events_reported);
528 }
529 
530 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
531 {
532 	struct ib_uevent_object *uobj;
533 
534 	/* for XRC target qp's, check that qp is live */
535 	if (!event->element.qp->uobject)
536 		return;
537 
538 	uobj = container_of(event->element.qp->uobject,
539 			    struct ib_uevent_object, uobject);
540 
541 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
542 				event->event, &uobj->event_list,
543 				&uobj->events_reported);
544 }
545 
546 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
547 {
548 	struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
549 						  struct ib_uevent_object, uobject);
550 
551 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
552 				event->event, &uobj->event_list,
553 				&uobj->events_reported);
554 }
555 
556 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
557 {
558 	struct ib_uevent_object *uobj;
559 
560 	uobj = container_of(event->element.srq->uobject,
561 			    struct ib_uevent_object, uobject);
562 
563 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
564 				event->event, &uobj->event_list,
565 				&uobj->events_reported);
566 }
567 
568 void ib_uverbs_event_handler(struct ib_event_handler *handler,
569 			     struct ib_event *event)
570 {
571 	struct ib_uverbs_file *file =
572 		container_of(handler, struct ib_uverbs_file, event_handler);
573 
574 	ib_uverbs_async_handler(file, event->element.port_num, event->event,
575 				NULL, NULL);
576 }
577 
578 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
579 {
580 	kref_put(&file->async_file->ref, ib_uverbs_release_async_event_file);
581 	file->async_file = NULL;
582 }
583 
584 void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue)
585 {
586 	spin_lock_init(&ev_queue->lock);
587 	INIT_LIST_HEAD(&ev_queue->event_list);
588 	init_waitqueue_head(&ev_queue->poll_wait);
589 	ev_queue->is_closed   = 0;
590 	ev_queue->async_queue = NULL;
591 }
592 
593 struct file *ib_uverbs_alloc_async_event_file(struct ib_uverbs_file *uverbs_file,
594 					      struct ib_device	*ib_dev)
595 {
596 	struct ib_uverbs_async_event_file *ev_file;
597 	struct file *filp;
598 	int ret;
599 
600 	ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
601 	if (!ev_file)
602 		return ERR_PTR(-ENOMEM);
603 
604 	ib_uverbs_init_event_queue(&ev_file->ev_queue);
605 	ev_file->uverbs_file = uverbs_file;
606 	kref_get(&ev_file->uverbs_file->ref);
607 	kref_init(&ev_file->ref);
608 	filp = anon_inode_getfile("[infinibandevent]", &uverbs_async_event_fops,
609 				  ev_file, O_RDONLY);
610 	if (IS_ERR(filp))
611 		goto err_put_refs;
612 
613 	mutex_lock(&uverbs_file->device->lists_mutex);
614 	list_add_tail(&ev_file->list,
615 		      &uverbs_file->device->uverbs_events_file_list);
616 	mutex_unlock(&uverbs_file->device->lists_mutex);
617 
618 	WARN_ON(uverbs_file->async_file);
619 	uverbs_file->async_file = ev_file;
620 	kref_get(&uverbs_file->async_file->ref);
621 	INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
622 			      ib_dev,
623 			      ib_uverbs_event_handler);
624 	ret = ib_register_event_handler(&uverbs_file->event_handler);
625 	if (ret)
626 		goto err_put_file;
627 
628 	/* At that point async file stuff was fully set */
629 
630 	return filp;
631 
632 err_put_file:
633 	fput(filp);
634 	kref_put(&uverbs_file->async_file->ref,
635 		 ib_uverbs_release_async_event_file);
636 	uverbs_file->async_file = NULL;
637 	return ERR_PTR(ret);
638 
639 err_put_refs:
640 	kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
641 	kref_put(&ev_file->ref, ib_uverbs_release_async_event_file);
642 	return filp;
643 }
644 
645 static int verify_command_mask(struct ib_device *ib_dev, __u32 command)
646 {
647 	u64 mask;
648 
649 	if (command <= IB_USER_VERBS_CMD_OPEN_QP)
650 		mask = ib_dev->uverbs_cmd_mask;
651 	else
652 		mask = ib_dev->uverbs_ex_cmd_mask;
653 
654 	if (mask & ((u64)1 << command))
655 		return 0;
656 
657 	return -1;
658 }
659 
660 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
661 			     size_t count, loff_t *pos)
662 {
663 	struct ib_uverbs_file *file = filp->private_data;
664 	struct ib_device *ib_dev;
665 	struct ib_uverbs_cmd_hdr hdr;
666 	__u32 command;
667 	__u32 flags;
668 	int srcu_key;
669 	ssize_t ret;
670 
671 	if (!ib_safe_file_access(filp)) {
672 		pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
673 			    task_tgid_vnr(current), current->comm);
674 		return -EACCES;
675 	}
676 
677 	if (count < sizeof hdr)
678 		return -EINVAL;
679 
680 	if (copy_from_user(&hdr, buf, sizeof hdr))
681 		return -EFAULT;
682 
683 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
684 	ib_dev = srcu_dereference(file->device->ib_dev,
685 				  &file->device->disassociate_srcu);
686 	if (!ib_dev) {
687 		ret = -EIO;
688 		goto out;
689 	}
690 
691 	if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
692 				   IB_USER_VERBS_CMD_COMMAND_MASK)) {
693 		ret = -EINVAL;
694 		goto out;
695 	}
696 
697 	command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
698 	if (verify_command_mask(ib_dev, command)) {
699 		ret = -EOPNOTSUPP;
700 		goto out;
701 	}
702 
703 	if (!file->ucontext &&
704 	    command != IB_USER_VERBS_CMD_GET_CONTEXT) {
705 		ret = -EINVAL;
706 		goto out;
707 	}
708 
709 	flags = (hdr.command &
710 		 IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
711 
712 	if (!flags) {
713 		if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
714 		    !uverbs_cmd_table[command]) {
715 			ret = -EINVAL;
716 			goto out;
717 		}
718 
719 		if (hdr.in_words * 4 != count) {
720 			ret = -EINVAL;
721 			goto out;
722 		}
723 
724 		ret = uverbs_cmd_table[command](file, ib_dev,
725 						 buf + sizeof(hdr),
726 						 hdr.in_words * 4,
727 						 hdr.out_words * 4);
728 
729 	} else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
730 		struct ib_uverbs_ex_cmd_hdr ex_hdr;
731 		struct ib_udata ucore;
732 		struct ib_udata uhw;
733 		size_t written_count = count;
734 
735 		if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
736 		    !uverbs_ex_cmd_table[command]) {
737 			ret = -ENOSYS;
738 			goto out;
739 		}
740 
741 		if (!file->ucontext) {
742 			ret = -EINVAL;
743 			goto out;
744 		}
745 
746 		if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
747 			ret = -EINVAL;
748 			goto out;
749 		}
750 
751 		if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
752 			ret = -EFAULT;
753 			goto out;
754 		}
755 
756 		count -= sizeof(hdr) + sizeof(ex_hdr);
757 		buf += sizeof(hdr) + sizeof(ex_hdr);
758 
759 		if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
760 			ret = -EINVAL;
761 			goto out;
762 		}
763 
764 		if (ex_hdr.cmd_hdr_reserved) {
765 			ret = -EINVAL;
766 			goto out;
767 		}
768 
769 		if (ex_hdr.response) {
770 			if (!hdr.out_words && !ex_hdr.provider_out_words) {
771 				ret = -EINVAL;
772 				goto out;
773 			}
774 
775 			if (!access_ok(VERIFY_WRITE,
776 				       (void __user *) (unsigned long) ex_hdr.response,
777 				       (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
778 				ret = -EFAULT;
779 				goto out;
780 			}
781 		} else {
782 			if (hdr.out_words || ex_hdr.provider_out_words) {
783 				ret = -EINVAL;
784 				goto out;
785 			}
786 		}
787 
788 		INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
789 				       hdr.in_words * 8, hdr.out_words * 8);
790 
791 		INIT_UDATA_BUF_OR_NULL(&uhw,
792 				       buf + ucore.inlen,
793 				       (unsigned long) ex_hdr.response + ucore.outlen,
794 				       ex_hdr.provider_in_words * 8,
795 				       ex_hdr.provider_out_words * 8);
796 
797 		ret = uverbs_ex_cmd_table[command](file,
798 						   ib_dev,
799 						   &ucore,
800 						   &uhw);
801 		if (!ret)
802 			ret = written_count;
803 	} else {
804 		ret = -ENOSYS;
805 	}
806 
807 out:
808 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
809 	return ret;
810 }
811 
812 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
813 {
814 	struct ib_uverbs_file *file = filp->private_data;
815 	struct ib_device *ib_dev;
816 	int ret = 0;
817 	int srcu_key;
818 
819 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
820 	ib_dev = srcu_dereference(file->device->ib_dev,
821 				  &file->device->disassociate_srcu);
822 	if (!ib_dev) {
823 		ret = -EIO;
824 		goto out;
825 	}
826 
827 	if (!file->ucontext)
828 		ret = -ENODEV;
829 	else
830 		ret = ib_dev->mmap(file->ucontext, vma);
831 out:
832 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
833 	return ret;
834 }
835 
836 /*
837  * ib_uverbs_open() does not need the BKL:
838  *
839  *  - the ib_uverbs_device structures are properly reference counted and
840  *    everything else is purely local to the file being created, so
841  *    races against other open calls are not a problem;
842  *  - there is no ioctl method to race against;
843  *  - the open method will either immediately run -ENXIO, or all
844  *    required initialization will be done.
845  */
846 static int ib_uverbs_open(struct inode *inode, struct file *filp)
847 {
848 	struct ib_uverbs_device *dev;
849 	struct ib_uverbs_file *file;
850 	struct ib_device *ib_dev;
851 	int ret;
852 	int module_dependent;
853 	int srcu_key;
854 
855 	dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
856 	if (!atomic_inc_not_zero(&dev->refcount))
857 		return -ENXIO;
858 
859 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
860 	mutex_lock(&dev->lists_mutex);
861 	ib_dev = srcu_dereference(dev->ib_dev,
862 				  &dev->disassociate_srcu);
863 	if (!ib_dev) {
864 		ret = -EIO;
865 		goto err;
866 	}
867 
868 	/* In case IB device supports disassociate ucontext, there is no hard
869 	 * dependency between uverbs device and its low level device.
870 	 */
871 	module_dependent = !(ib_dev->disassociate_ucontext);
872 
873 	if (module_dependent) {
874 		if (!try_module_get(ib_dev->owner)) {
875 			ret = -ENODEV;
876 			goto err;
877 		}
878 	}
879 
880 	file = kzalloc(sizeof(*file), GFP_KERNEL);
881 	if (!file) {
882 		ret = -ENOMEM;
883 		if (module_dependent)
884 			goto err_module;
885 
886 		goto err;
887 	}
888 
889 	file->device	 = dev;
890 	spin_lock_init(&file->idr_lock);
891 	idr_init(&file->idr);
892 	file->ucontext	 = NULL;
893 	file->async_file = NULL;
894 	kref_init(&file->ref);
895 	mutex_init(&file->mutex);
896 	mutex_init(&file->cleanup_mutex);
897 
898 	filp->private_data = file;
899 	kobject_get(&dev->kobj);
900 	list_add_tail(&file->list, &dev->uverbs_file_list);
901 	mutex_unlock(&dev->lists_mutex);
902 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
903 
904 	return nonseekable_open(inode, filp);
905 
906 err_module:
907 	module_put(ib_dev->owner);
908 
909 err:
910 	mutex_unlock(&dev->lists_mutex);
911 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
912 	if (atomic_dec_and_test(&dev->refcount))
913 		ib_uverbs_comp_dev(dev);
914 
915 	return ret;
916 }
917 
918 static int ib_uverbs_close(struct inode *inode, struct file *filp)
919 {
920 	struct ib_uverbs_file *file = filp->private_data;
921 
922 	mutex_lock(&file->cleanup_mutex);
923 	if (file->ucontext) {
924 		ib_uverbs_cleanup_ucontext(file, file->ucontext, false);
925 		file->ucontext = NULL;
926 	}
927 	mutex_unlock(&file->cleanup_mutex);
928 	idr_destroy(&file->idr);
929 
930 	mutex_lock(&file->device->lists_mutex);
931 	if (!file->is_closed) {
932 		list_del(&file->list);
933 		file->is_closed = 1;
934 	}
935 	mutex_unlock(&file->device->lists_mutex);
936 
937 	if (file->async_file)
938 		kref_put(&file->async_file->ref,
939 			 ib_uverbs_release_async_event_file);
940 
941 	kref_put(&file->ref, ib_uverbs_release_file);
942 
943 	return 0;
944 }
945 
946 static const struct file_operations uverbs_fops = {
947 	.owner	 = THIS_MODULE,
948 	.write	 = ib_uverbs_write,
949 	.open	 = ib_uverbs_open,
950 	.release = ib_uverbs_close,
951 	.llseek	 = no_llseek,
952 };
953 
954 static const struct file_operations uverbs_mmap_fops = {
955 	.owner	 = THIS_MODULE,
956 	.write	 = ib_uverbs_write,
957 	.mmap    = ib_uverbs_mmap,
958 	.open	 = ib_uverbs_open,
959 	.release = ib_uverbs_close,
960 	.llseek	 = no_llseek,
961 };
962 
963 static struct ib_client uverbs_client = {
964 	.name   = "uverbs",
965 	.add    = ib_uverbs_add_one,
966 	.remove = ib_uverbs_remove_one
967 };
968 
969 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
970 			  char *buf)
971 {
972 	int ret = -ENODEV;
973 	int srcu_key;
974 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
975 	struct ib_device *ib_dev;
976 
977 	if (!dev)
978 		return -ENODEV;
979 
980 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
981 	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
982 	if (ib_dev)
983 		ret = sprintf(buf, "%s\n", ib_dev->name);
984 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
985 
986 	return ret;
987 }
988 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
989 
990 static ssize_t show_dev_abi_version(struct device *device,
991 				    struct device_attribute *attr, char *buf)
992 {
993 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
994 	int ret = -ENODEV;
995 	int srcu_key;
996 	struct ib_device *ib_dev;
997 
998 	if (!dev)
999 		return -ENODEV;
1000 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1001 	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1002 	if (ib_dev)
1003 		ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1004 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1005 
1006 	return ret;
1007 }
1008 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1009 
1010 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1011 			 __stringify(IB_USER_VERBS_ABI_VERSION));
1012 
1013 static dev_t overflow_maj;
1014 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
1015 
1016 /*
1017  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
1018  * requesting a new major number and doubling the number of max devices we
1019  * support. It's stupid, but simple.
1020  */
1021 static int find_overflow_devnum(void)
1022 {
1023 	int ret;
1024 
1025 	if (!overflow_maj) {
1026 		ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
1027 					  "infiniband_verbs");
1028 		if (ret) {
1029 			pr_err("user_verbs: couldn't register dynamic device number\n");
1030 			return ret;
1031 		}
1032 	}
1033 
1034 	ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
1035 	if (ret >= IB_UVERBS_MAX_DEVICES)
1036 		return -1;
1037 
1038 	return ret;
1039 }
1040 
1041 static void ib_uverbs_add_one(struct ib_device *device)
1042 {
1043 	int devnum;
1044 	dev_t base;
1045 	struct ib_uverbs_device *uverbs_dev;
1046 	int ret;
1047 
1048 	if (!device->alloc_ucontext)
1049 		return;
1050 
1051 	uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1052 	if (!uverbs_dev)
1053 		return;
1054 
1055 	ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1056 	if (ret) {
1057 		kfree(uverbs_dev);
1058 		return;
1059 	}
1060 
1061 	atomic_set(&uverbs_dev->refcount, 1);
1062 	init_completion(&uverbs_dev->comp);
1063 	uverbs_dev->xrcd_tree = RB_ROOT;
1064 	mutex_init(&uverbs_dev->xrcd_tree_mutex);
1065 	kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1066 	mutex_init(&uverbs_dev->lists_mutex);
1067 	INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1068 	INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1069 
1070 	spin_lock(&map_lock);
1071 	devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1072 	if (devnum >= IB_UVERBS_MAX_DEVICES) {
1073 		spin_unlock(&map_lock);
1074 		devnum = find_overflow_devnum();
1075 		if (devnum < 0)
1076 			goto err;
1077 
1078 		spin_lock(&map_lock);
1079 		uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
1080 		base = devnum + overflow_maj;
1081 		set_bit(devnum, overflow_map);
1082 	} else {
1083 		uverbs_dev->devnum = devnum;
1084 		base = devnum + IB_UVERBS_BASE_DEV;
1085 		set_bit(devnum, dev_map);
1086 	}
1087 	spin_unlock(&map_lock);
1088 
1089 	rcu_assign_pointer(uverbs_dev->ib_dev, device);
1090 	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1091 
1092 	cdev_init(&uverbs_dev->cdev, NULL);
1093 	uverbs_dev->cdev.owner = THIS_MODULE;
1094 	uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1095 	cdev_set_parent(&uverbs_dev->cdev, &uverbs_dev->kobj);
1096 	kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1097 	if (cdev_add(&uverbs_dev->cdev, base, 1))
1098 		goto err_cdev;
1099 
1100 	uverbs_dev->dev = device_create(uverbs_class, device->dev.parent,
1101 					uverbs_dev->cdev.dev, uverbs_dev,
1102 					"uverbs%d", uverbs_dev->devnum);
1103 	if (IS_ERR(uverbs_dev->dev))
1104 		goto err_cdev;
1105 
1106 	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1107 		goto err_class;
1108 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1109 		goto err_class;
1110 
1111 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
1112 
1113 	return;
1114 
1115 err_class:
1116 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1117 
1118 err_cdev:
1119 	cdev_del(&uverbs_dev->cdev);
1120 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1121 		clear_bit(devnum, dev_map);
1122 	else
1123 		clear_bit(devnum, overflow_map);
1124 
1125 err:
1126 	if (atomic_dec_and_test(&uverbs_dev->refcount))
1127 		ib_uverbs_comp_dev(uverbs_dev);
1128 	wait_for_completion(&uverbs_dev->comp);
1129 	kobject_put(&uverbs_dev->kobj);
1130 	return;
1131 }
1132 
1133 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1134 					struct ib_device *ib_dev)
1135 {
1136 	struct ib_uverbs_file *file;
1137 	struct ib_uverbs_async_event_file *event_file;
1138 	struct ib_event event;
1139 
1140 	/* Pending running commands to terminate */
1141 	synchronize_srcu(&uverbs_dev->disassociate_srcu);
1142 	event.event = IB_EVENT_DEVICE_FATAL;
1143 	event.element.port_num = 0;
1144 	event.device = ib_dev;
1145 
1146 	mutex_lock(&uverbs_dev->lists_mutex);
1147 	while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1148 		struct ib_ucontext *ucontext;
1149 		file = list_first_entry(&uverbs_dev->uverbs_file_list,
1150 					struct ib_uverbs_file, list);
1151 		file->is_closed = 1;
1152 		list_del(&file->list);
1153 		kref_get(&file->ref);
1154 		mutex_unlock(&uverbs_dev->lists_mutex);
1155 
1156 
1157 		mutex_lock(&file->cleanup_mutex);
1158 		ucontext = file->ucontext;
1159 		file->ucontext = NULL;
1160 		mutex_unlock(&file->cleanup_mutex);
1161 
1162 		/* At this point ib_uverbs_close cannot be running
1163 		 * ib_uverbs_cleanup_ucontext
1164 		 */
1165 		if (ucontext) {
1166 			/* We must release the mutex before going ahead and
1167 			 * calling disassociate_ucontext. disassociate_ucontext
1168 			 * might end up indirectly calling uverbs_close,
1169 			 * for example due to freeing the resources
1170 			 * (e.g mmput).
1171 			 */
1172 			ib_uverbs_event_handler(&file->event_handler, &event);
1173 			ib_dev->disassociate_ucontext(ucontext);
1174 			mutex_lock(&file->cleanup_mutex);
1175 			ib_uverbs_cleanup_ucontext(file, ucontext, true);
1176 			mutex_unlock(&file->cleanup_mutex);
1177 		}
1178 
1179 		mutex_lock(&uverbs_dev->lists_mutex);
1180 		kref_put(&file->ref, ib_uverbs_release_file);
1181 	}
1182 
1183 	while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1184 		event_file = list_first_entry(&uverbs_dev->
1185 					      uverbs_events_file_list,
1186 					      struct ib_uverbs_async_event_file,
1187 					      list);
1188 		spin_lock_irq(&event_file->ev_queue.lock);
1189 		event_file->ev_queue.is_closed = 1;
1190 		spin_unlock_irq(&event_file->ev_queue.lock);
1191 
1192 		list_del(&event_file->list);
1193 		ib_unregister_event_handler(
1194 			&event_file->uverbs_file->event_handler);
1195 		event_file->uverbs_file->event_handler.device =
1196 			NULL;
1197 
1198 		wake_up_interruptible(&event_file->ev_queue.poll_wait);
1199 		kill_fasync(&event_file->ev_queue.async_queue, SIGIO, POLL_IN);
1200 	}
1201 	mutex_unlock(&uverbs_dev->lists_mutex);
1202 }
1203 
1204 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1205 {
1206 	struct ib_uverbs_device *uverbs_dev = client_data;
1207 	int wait_clients = 1;
1208 
1209 	if (!uverbs_dev)
1210 		return;
1211 
1212 	dev_set_drvdata(uverbs_dev->dev, NULL);
1213 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1214 	cdev_del(&uverbs_dev->cdev);
1215 
1216 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1217 		clear_bit(uverbs_dev->devnum, dev_map);
1218 	else
1219 		clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
1220 
1221 	if (device->disassociate_ucontext) {
1222 		/* We disassociate HW resources and immediately return.
1223 		 * Userspace will see a EIO errno for all future access.
1224 		 * Upon returning, ib_device may be freed internally and is not
1225 		 * valid any more.
1226 		 * uverbs_device is still available until all clients close
1227 		 * their files, then the uverbs device ref count will be zero
1228 		 * and its resources will be freed.
1229 		 * Note: At this point no more files can be opened since the
1230 		 * cdev was deleted, however active clients can still issue
1231 		 * commands and close their open files.
1232 		 */
1233 		rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1234 		ib_uverbs_free_hw_resources(uverbs_dev, device);
1235 		wait_clients = 0;
1236 	}
1237 
1238 	if (atomic_dec_and_test(&uverbs_dev->refcount))
1239 		ib_uverbs_comp_dev(uverbs_dev);
1240 	if (wait_clients)
1241 		wait_for_completion(&uverbs_dev->comp);
1242 	kobject_put(&uverbs_dev->kobj);
1243 }
1244 
1245 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1246 {
1247 	if (mode)
1248 		*mode = 0666;
1249 	return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1250 }
1251 
1252 static int __init ib_uverbs_init(void)
1253 {
1254 	int ret;
1255 
1256 	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
1257 				     "infiniband_verbs");
1258 	if (ret) {
1259 		pr_err("user_verbs: couldn't register device number\n");
1260 		goto out;
1261 	}
1262 
1263 	uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1264 	if (IS_ERR(uverbs_class)) {
1265 		ret = PTR_ERR(uverbs_class);
1266 		pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1267 		goto out_chrdev;
1268 	}
1269 
1270 	uverbs_class->devnode = uverbs_devnode;
1271 
1272 	ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1273 	if (ret) {
1274 		pr_err("user_verbs: couldn't create abi_version attribute\n");
1275 		goto out_class;
1276 	}
1277 
1278 	ret = ib_register_client(&uverbs_client);
1279 	if (ret) {
1280 		pr_err("user_verbs: couldn't register client\n");
1281 		goto out_class;
1282 	}
1283 
1284 	return 0;
1285 
1286 out_class:
1287 	class_destroy(uverbs_class);
1288 
1289 out_chrdev:
1290 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1291 
1292 out:
1293 	return ret;
1294 }
1295 
1296 static void __exit ib_uverbs_cleanup(void)
1297 {
1298 	ib_unregister_client(&uverbs_client);
1299 	class_destroy(uverbs_class);
1300 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1301 	if (overflow_maj)
1302 		unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1303 }
1304 
1305 module_init(ib_uverbs_init);
1306 module_exit(ib_uverbs_cleanup);
1307