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 <rdma/ib.h>
52 
53 #include "uverbs.h"
54 
55 MODULE_AUTHOR("Roland Dreier");
56 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
57 MODULE_LICENSE("Dual BSD/GPL");
58 
59 enum {
60 	IB_UVERBS_MAJOR       = 231,
61 	IB_UVERBS_BASE_MINOR  = 192,
62 	IB_UVERBS_MAX_DEVICES = 32
63 };
64 
65 #define IB_UVERBS_BASE_DEV	MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
66 
67 static struct class *uverbs_class;
68 
69 DEFINE_SPINLOCK(ib_uverbs_idr_lock);
70 DEFINE_IDR(ib_uverbs_pd_idr);
71 DEFINE_IDR(ib_uverbs_mr_idr);
72 DEFINE_IDR(ib_uverbs_mw_idr);
73 DEFINE_IDR(ib_uverbs_ah_idr);
74 DEFINE_IDR(ib_uverbs_cq_idr);
75 DEFINE_IDR(ib_uverbs_qp_idr);
76 DEFINE_IDR(ib_uverbs_srq_idr);
77 DEFINE_IDR(ib_uverbs_xrcd_idr);
78 DEFINE_IDR(ib_uverbs_rule_idr);
79 DEFINE_IDR(ib_uverbs_wq_idr);
80 DEFINE_IDR(ib_uverbs_rwq_ind_tbl_idr);
81 
82 static DEFINE_SPINLOCK(map_lock);
83 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
84 
85 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
86 				     struct ib_device *ib_dev,
87 				     const char __user *buf, int in_len,
88 				     int out_len) = {
89 	[IB_USER_VERBS_CMD_GET_CONTEXT]		= ib_uverbs_get_context,
90 	[IB_USER_VERBS_CMD_QUERY_DEVICE]	= ib_uverbs_query_device,
91 	[IB_USER_VERBS_CMD_QUERY_PORT]		= ib_uverbs_query_port,
92 	[IB_USER_VERBS_CMD_ALLOC_PD]		= ib_uverbs_alloc_pd,
93 	[IB_USER_VERBS_CMD_DEALLOC_PD]		= ib_uverbs_dealloc_pd,
94 	[IB_USER_VERBS_CMD_REG_MR]		= ib_uverbs_reg_mr,
95 	[IB_USER_VERBS_CMD_REREG_MR]		= ib_uverbs_rereg_mr,
96 	[IB_USER_VERBS_CMD_DEREG_MR]		= ib_uverbs_dereg_mr,
97 	[IB_USER_VERBS_CMD_ALLOC_MW]		= ib_uverbs_alloc_mw,
98 	[IB_USER_VERBS_CMD_DEALLOC_MW]		= ib_uverbs_dealloc_mw,
99 	[IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
100 	[IB_USER_VERBS_CMD_CREATE_CQ]		= ib_uverbs_create_cq,
101 	[IB_USER_VERBS_CMD_RESIZE_CQ]		= ib_uverbs_resize_cq,
102 	[IB_USER_VERBS_CMD_POLL_CQ]		= ib_uverbs_poll_cq,
103 	[IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]	= ib_uverbs_req_notify_cq,
104 	[IB_USER_VERBS_CMD_DESTROY_CQ]		= ib_uverbs_destroy_cq,
105 	[IB_USER_VERBS_CMD_CREATE_QP]		= ib_uverbs_create_qp,
106 	[IB_USER_VERBS_CMD_QUERY_QP]		= ib_uverbs_query_qp,
107 	[IB_USER_VERBS_CMD_MODIFY_QP]		= ib_uverbs_modify_qp,
108 	[IB_USER_VERBS_CMD_DESTROY_QP]		= ib_uverbs_destroy_qp,
109 	[IB_USER_VERBS_CMD_POST_SEND]		= ib_uverbs_post_send,
110 	[IB_USER_VERBS_CMD_POST_RECV]		= ib_uverbs_post_recv,
111 	[IB_USER_VERBS_CMD_POST_SRQ_RECV]	= ib_uverbs_post_srq_recv,
112 	[IB_USER_VERBS_CMD_CREATE_AH]		= ib_uverbs_create_ah,
113 	[IB_USER_VERBS_CMD_DESTROY_AH]		= ib_uverbs_destroy_ah,
114 	[IB_USER_VERBS_CMD_ATTACH_MCAST]	= ib_uverbs_attach_mcast,
115 	[IB_USER_VERBS_CMD_DETACH_MCAST]	= ib_uverbs_detach_mcast,
116 	[IB_USER_VERBS_CMD_CREATE_SRQ]		= ib_uverbs_create_srq,
117 	[IB_USER_VERBS_CMD_MODIFY_SRQ]		= ib_uverbs_modify_srq,
118 	[IB_USER_VERBS_CMD_QUERY_SRQ]		= ib_uverbs_query_srq,
119 	[IB_USER_VERBS_CMD_DESTROY_SRQ]		= ib_uverbs_destroy_srq,
120 	[IB_USER_VERBS_CMD_OPEN_XRCD]		= ib_uverbs_open_xrcd,
121 	[IB_USER_VERBS_CMD_CLOSE_XRCD]		= ib_uverbs_close_xrcd,
122 	[IB_USER_VERBS_CMD_CREATE_XSRQ]		= ib_uverbs_create_xsrq,
123 	[IB_USER_VERBS_CMD_OPEN_QP]		= ib_uverbs_open_qp,
124 };
125 
126 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
127 				    struct ib_device *ib_dev,
128 				    struct ib_udata *ucore,
129 				    struct ib_udata *uhw) = {
130 	[IB_USER_VERBS_EX_CMD_CREATE_FLOW]	= ib_uverbs_ex_create_flow,
131 	[IB_USER_VERBS_EX_CMD_DESTROY_FLOW]	= ib_uverbs_ex_destroy_flow,
132 	[IB_USER_VERBS_EX_CMD_QUERY_DEVICE]	= ib_uverbs_ex_query_device,
133 	[IB_USER_VERBS_EX_CMD_CREATE_CQ]	= ib_uverbs_ex_create_cq,
134 	[IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
135 	[IB_USER_VERBS_EX_CMD_CREATE_WQ]        = ib_uverbs_ex_create_wq,
136 	[IB_USER_VERBS_EX_CMD_MODIFY_WQ]        = ib_uverbs_ex_modify_wq,
137 	[IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
138 	[IB_USER_VERBS_EX_CMD_CREATE_RWQ_IND_TBL] = ib_uverbs_ex_create_rwq_ind_table,
139 	[IB_USER_VERBS_EX_CMD_DESTROY_RWQ_IND_TBL] = ib_uverbs_ex_destroy_rwq_ind_table,
140 };
141 
142 static void ib_uverbs_add_one(struct ib_device *device);
143 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
144 
145 int uverbs_dealloc_mw(struct ib_mw *mw)
146 {
147 	struct ib_pd *pd = mw->pd;
148 	int ret;
149 
150 	ret = mw->device->dealloc_mw(mw);
151 	if (!ret)
152 		atomic_dec(&pd->usecnt);
153 	return ret;
154 }
155 
156 static void ib_uverbs_release_dev(struct kobject *kobj)
157 {
158 	struct ib_uverbs_device *dev =
159 		container_of(kobj, struct ib_uverbs_device, kobj);
160 
161 	cleanup_srcu_struct(&dev->disassociate_srcu);
162 	kfree(dev);
163 }
164 
165 static struct kobj_type ib_uverbs_dev_ktype = {
166 	.release = ib_uverbs_release_dev,
167 };
168 
169 static void ib_uverbs_release_event_file(struct kref *ref)
170 {
171 	struct ib_uverbs_event_file *file =
172 		container_of(ref, struct ib_uverbs_event_file, ref);
173 
174 	kfree(file);
175 }
176 
177 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
178 			  struct ib_uverbs_event_file *ev_file,
179 			  struct ib_ucq_object *uobj)
180 {
181 	struct ib_uverbs_event *evt, *tmp;
182 
183 	if (ev_file) {
184 		spin_lock_irq(&ev_file->lock);
185 		list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
186 			list_del(&evt->list);
187 			kfree(evt);
188 		}
189 		spin_unlock_irq(&ev_file->lock);
190 
191 		kref_put(&ev_file->ref, ib_uverbs_release_event_file);
192 	}
193 
194 	spin_lock_irq(&file->async_file->lock);
195 	list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
196 		list_del(&evt->list);
197 		kfree(evt);
198 	}
199 	spin_unlock_irq(&file->async_file->lock);
200 }
201 
202 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
203 			      struct ib_uevent_object *uobj)
204 {
205 	struct ib_uverbs_event *evt, *tmp;
206 
207 	spin_lock_irq(&file->async_file->lock);
208 	list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
209 		list_del(&evt->list);
210 		kfree(evt);
211 	}
212 	spin_unlock_irq(&file->async_file->lock);
213 }
214 
215 static void ib_uverbs_detach_umcast(struct ib_qp *qp,
216 				    struct ib_uqp_object *uobj)
217 {
218 	struct ib_uverbs_mcast_entry *mcast, *tmp;
219 
220 	list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
221 		ib_detach_mcast(qp, &mcast->gid, mcast->lid);
222 		list_del(&mcast->list);
223 		kfree(mcast);
224 	}
225 }
226 
227 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
228 				      struct ib_ucontext *context)
229 {
230 	struct ib_uobject *uobj, *tmp;
231 
232 	context->closing = 1;
233 
234 	list_for_each_entry_safe(uobj, tmp, &context->ah_list, list) {
235 		struct ib_ah *ah = uobj->object;
236 
237 		idr_remove_uobj(&ib_uverbs_ah_idr, uobj);
238 		ib_destroy_ah(ah);
239 		kfree(uobj);
240 	}
241 
242 	/* Remove MWs before QPs, in order to support type 2A MWs. */
243 	list_for_each_entry_safe(uobj, tmp, &context->mw_list, list) {
244 		struct ib_mw *mw = uobj->object;
245 
246 		idr_remove_uobj(&ib_uverbs_mw_idr, uobj);
247 		uverbs_dealloc_mw(mw);
248 		kfree(uobj);
249 	}
250 
251 	list_for_each_entry_safe(uobj, tmp, &context->rule_list, list) {
252 		struct ib_flow *flow_id = uobj->object;
253 
254 		idr_remove_uobj(&ib_uverbs_rule_idr, uobj);
255 		ib_destroy_flow(flow_id);
256 		kfree(uobj);
257 	}
258 
259 	list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {
260 		struct ib_qp *qp = uobj->object;
261 		struct ib_uqp_object *uqp =
262 			container_of(uobj, struct ib_uqp_object, uevent.uobject);
263 
264 		idr_remove_uobj(&ib_uverbs_qp_idr, uobj);
265 		if (qp != qp->real_qp) {
266 			ib_close_qp(qp);
267 		} else {
268 			ib_uverbs_detach_umcast(qp, uqp);
269 			ib_destroy_qp(qp);
270 		}
271 		ib_uverbs_release_uevent(file, &uqp->uevent);
272 		kfree(uqp);
273 	}
274 
275 	list_for_each_entry_safe(uobj, tmp, &context->rwq_ind_tbl_list, list) {
276 		struct ib_rwq_ind_table *rwq_ind_tbl = uobj->object;
277 		struct ib_wq **ind_tbl = rwq_ind_tbl->ind_tbl;
278 
279 		idr_remove_uobj(&ib_uverbs_rwq_ind_tbl_idr, uobj);
280 		ib_destroy_rwq_ind_table(rwq_ind_tbl);
281 		kfree(ind_tbl);
282 		kfree(uobj);
283 	}
284 
285 	list_for_each_entry_safe(uobj, tmp, &context->wq_list, list) {
286 		struct ib_wq *wq = uobj->object;
287 		struct ib_uwq_object *uwq =
288 			container_of(uobj, struct ib_uwq_object, uevent.uobject);
289 
290 		idr_remove_uobj(&ib_uverbs_wq_idr, uobj);
291 		ib_destroy_wq(wq);
292 		ib_uverbs_release_uevent(file, &uwq->uevent);
293 		kfree(uwq);
294 	}
295 
296 	list_for_each_entry_safe(uobj, tmp, &context->srq_list, list) {
297 		struct ib_srq *srq = uobj->object;
298 		struct ib_uevent_object *uevent =
299 			container_of(uobj, struct ib_uevent_object, uobject);
300 
301 		idr_remove_uobj(&ib_uverbs_srq_idr, uobj);
302 		ib_destroy_srq(srq);
303 		ib_uverbs_release_uevent(file, uevent);
304 		kfree(uevent);
305 	}
306 
307 	list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {
308 		struct ib_cq *cq = uobj->object;
309 		struct ib_uverbs_event_file *ev_file = cq->cq_context;
310 		struct ib_ucq_object *ucq =
311 			container_of(uobj, struct ib_ucq_object, uobject);
312 
313 		idr_remove_uobj(&ib_uverbs_cq_idr, uobj);
314 		ib_destroy_cq(cq);
315 		ib_uverbs_release_ucq(file, ev_file, ucq);
316 		kfree(ucq);
317 	}
318 
319 	list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {
320 		struct ib_mr *mr = uobj->object;
321 
322 		idr_remove_uobj(&ib_uverbs_mr_idr, uobj);
323 		ib_dereg_mr(mr);
324 		kfree(uobj);
325 	}
326 
327 	mutex_lock(&file->device->xrcd_tree_mutex);
328 	list_for_each_entry_safe(uobj, tmp, &context->xrcd_list, list) {
329 		struct ib_xrcd *xrcd = uobj->object;
330 		struct ib_uxrcd_object *uxrcd =
331 			container_of(uobj, struct ib_uxrcd_object, uobject);
332 
333 		idr_remove_uobj(&ib_uverbs_xrcd_idr, uobj);
334 		ib_uverbs_dealloc_xrcd(file->device, xrcd);
335 		kfree(uxrcd);
336 	}
337 	mutex_unlock(&file->device->xrcd_tree_mutex);
338 
339 	list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
340 		struct ib_pd *pd = uobj->object;
341 
342 		idr_remove_uobj(&ib_uverbs_pd_idr, uobj);
343 		ib_dealloc_pd(pd);
344 		kfree(uobj);
345 	}
346 
347 	put_pid(context->tgid);
348 
349 	return context->device->dealloc_ucontext(context);
350 }
351 
352 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
353 {
354 	complete(&dev->comp);
355 }
356 
357 static void ib_uverbs_release_file(struct kref *ref)
358 {
359 	struct ib_uverbs_file *file =
360 		container_of(ref, struct ib_uverbs_file, ref);
361 	struct ib_device *ib_dev;
362 	int srcu_key;
363 
364 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
365 	ib_dev = srcu_dereference(file->device->ib_dev,
366 				  &file->device->disassociate_srcu);
367 	if (ib_dev && !ib_dev->disassociate_ucontext)
368 		module_put(ib_dev->owner);
369 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
370 
371 	if (atomic_dec_and_test(&file->device->refcount))
372 		ib_uverbs_comp_dev(file->device);
373 
374 	kfree(file);
375 }
376 
377 static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,
378 				    size_t count, loff_t *pos)
379 {
380 	struct ib_uverbs_event_file *file = filp->private_data;
381 	struct ib_uverbs_event *event;
382 	int eventsz;
383 	int ret = 0;
384 
385 	spin_lock_irq(&file->lock);
386 
387 	while (list_empty(&file->event_list)) {
388 		spin_unlock_irq(&file->lock);
389 
390 		if (filp->f_flags & O_NONBLOCK)
391 			return -EAGAIN;
392 
393 		if (wait_event_interruptible(file->poll_wait,
394 					     (!list_empty(&file->event_list) ||
395 			/* The barriers built into wait_event_interruptible()
396 			 * and wake_up() guarentee this will see the null set
397 			 * without using RCU
398 			 */
399 					     !file->uverbs_file->device->ib_dev)))
400 			return -ERESTARTSYS;
401 
402 		/* If device was disassociated and no event exists set an error */
403 		if (list_empty(&file->event_list) &&
404 		    !file->uverbs_file->device->ib_dev)
405 			return -EIO;
406 
407 		spin_lock_irq(&file->lock);
408 	}
409 
410 	event = list_entry(file->event_list.next, struct ib_uverbs_event, list);
411 
412 	if (file->is_async)
413 		eventsz = sizeof (struct ib_uverbs_async_event_desc);
414 	else
415 		eventsz = sizeof (struct ib_uverbs_comp_event_desc);
416 
417 	if (eventsz > count) {
418 		ret   = -EINVAL;
419 		event = NULL;
420 	} else {
421 		list_del(file->event_list.next);
422 		if (event->counter) {
423 			++(*event->counter);
424 			list_del(&event->obj_list);
425 		}
426 	}
427 
428 	spin_unlock_irq(&file->lock);
429 
430 	if (event) {
431 		if (copy_to_user(buf, event, eventsz))
432 			ret = -EFAULT;
433 		else
434 			ret = eventsz;
435 	}
436 
437 	kfree(event);
438 
439 	return ret;
440 }
441 
442 static unsigned int ib_uverbs_event_poll(struct file *filp,
443 					 struct poll_table_struct *wait)
444 {
445 	unsigned int pollflags = 0;
446 	struct ib_uverbs_event_file *file = filp->private_data;
447 
448 	poll_wait(filp, &file->poll_wait, wait);
449 
450 	spin_lock_irq(&file->lock);
451 	if (!list_empty(&file->event_list))
452 		pollflags = POLLIN | POLLRDNORM;
453 	spin_unlock_irq(&file->lock);
454 
455 	return pollflags;
456 }
457 
458 static int ib_uverbs_event_fasync(int fd, struct file *filp, int on)
459 {
460 	struct ib_uverbs_event_file *file = filp->private_data;
461 
462 	return fasync_helper(fd, filp, on, &file->async_queue);
463 }
464 
465 static int ib_uverbs_event_close(struct inode *inode, struct file *filp)
466 {
467 	struct ib_uverbs_event_file *file = filp->private_data;
468 	struct ib_uverbs_event *entry, *tmp;
469 	int closed_already = 0;
470 
471 	mutex_lock(&file->uverbs_file->device->lists_mutex);
472 	spin_lock_irq(&file->lock);
473 	closed_already = file->is_closed;
474 	file->is_closed = 1;
475 	list_for_each_entry_safe(entry, tmp, &file->event_list, list) {
476 		if (entry->counter)
477 			list_del(&entry->obj_list);
478 		kfree(entry);
479 	}
480 	spin_unlock_irq(&file->lock);
481 	if (!closed_already) {
482 		list_del(&file->list);
483 		if (file->is_async)
484 			ib_unregister_event_handler(&file->uverbs_file->
485 				event_handler);
486 	}
487 	mutex_unlock(&file->uverbs_file->device->lists_mutex);
488 
489 	kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);
490 	kref_put(&file->ref, ib_uverbs_release_event_file);
491 
492 	return 0;
493 }
494 
495 static const struct file_operations uverbs_event_fops = {
496 	.owner	 = THIS_MODULE,
497 	.read	 = ib_uverbs_event_read,
498 	.poll    = ib_uverbs_event_poll,
499 	.release = ib_uverbs_event_close,
500 	.fasync  = ib_uverbs_event_fasync,
501 	.llseek	 = no_llseek,
502 };
503 
504 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
505 {
506 	struct ib_uverbs_event_file    *file = cq_context;
507 	struct ib_ucq_object	       *uobj;
508 	struct ib_uverbs_event	       *entry;
509 	unsigned long			flags;
510 
511 	if (!file)
512 		return;
513 
514 	spin_lock_irqsave(&file->lock, flags);
515 	if (file->is_closed) {
516 		spin_unlock_irqrestore(&file->lock, flags);
517 		return;
518 	}
519 
520 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
521 	if (!entry) {
522 		spin_unlock_irqrestore(&file->lock, flags);
523 		return;
524 	}
525 
526 	uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
527 
528 	entry->desc.comp.cq_handle = cq->uobject->user_handle;
529 	entry->counter		   = &uobj->comp_events_reported;
530 
531 	list_add_tail(&entry->list, &file->event_list);
532 	list_add_tail(&entry->obj_list, &uobj->comp_list);
533 	spin_unlock_irqrestore(&file->lock, flags);
534 
535 	wake_up_interruptible(&file->poll_wait);
536 	kill_fasync(&file->async_queue, SIGIO, POLL_IN);
537 }
538 
539 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
540 				    __u64 element, __u64 event,
541 				    struct list_head *obj_list,
542 				    u32 *counter)
543 {
544 	struct ib_uverbs_event *entry;
545 	unsigned long flags;
546 
547 	spin_lock_irqsave(&file->async_file->lock, flags);
548 	if (file->async_file->is_closed) {
549 		spin_unlock_irqrestore(&file->async_file->lock, flags);
550 		return;
551 	}
552 
553 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
554 	if (!entry) {
555 		spin_unlock_irqrestore(&file->async_file->lock, flags);
556 		return;
557 	}
558 
559 	entry->desc.async.element    = element;
560 	entry->desc.async.event_type = event;
561 	entry->desc.async.reserved   = 0;
562 	entry->counter               = counter;
563 
564 	list_add_tail(&entry->list, &file->async_file->event_list);
565 	if (obj_list)
566 		list_add_tail(&entry->obj_list, obj_list);
567 	spin_unlock_irqrestore(&file->async_file->lock, flags);
568 
569 	wake_up_interruptible(&file->async_file->poll_wait);
570 	kill_fasync(&file->async_file->async_queue, SIGIO, POLL_IN);
571 }
572 
573 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
574 {
575 	struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
576 						  struct ib_ucq_object, uobject);
577 
578 	ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
579 				event->event, &uobj->async_list,
580 				&uobj->async_events_reported);
581 }
582 
583 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
584 {
585 	struct ib_uevent_object *uobj;
586 
587 	/* for XRC target qp's, check that qp is live */
588 	if (!event->element.qp->uobject || !event->element.qp->uobject->live)
589 		return;
590 
591 	uobj = container_of(event->element.qp->uobject,
592 			    struct ib_uevent_object, uobject);
593 
594 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
595 				event->event, &uobj->event_list,
596 				&uobj->events_reported);
597 }
598 
599 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
600 {
601 	struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
602 						  struct ib_uevent_object, uobject);
603 
604 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
605 				event->event, &uobj->event_list,
606 				&uobj->events_reported);
607 }
608 
609 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
610 {
611 	struct ib_uevent_object *uobj;
612 
613 	uobj = container_of(event->element.srq->uobject,
614 			    struct ib_uevent_object, uobject);
615 
616 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
617 				event->event, &uobj->event_list,
618 				&uobj->events_reported);
619 }
620 
621 void ib_uverbs_event_handler(struct ib_event_handler *handler,
622 			     struct ib_event *event)
623 {
624 	struct ib_uverbs_file *file =
625 		container_of(handler, struct ib_uverbs_file, event_handler);
626 
627 	ib_uverbs_async_handler(file, event->element.port_num, event->event,
628 				NULL, NULL);
629 }
630 
631 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
632 {
633 	kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
634 	file->async_file = NULL;
635 }
636 
637 struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
638 					struct ib_device	*ib_dev,
639 					int is_async)
640 {
641 	struct ib_uverbs_event_file *ev_file;
642 	struct file *filp;
643 	int ret;
644 
645 	ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
646 	if (!ev_file)
647 		return ERR_PTR(-ENOMEM);
648 
649 	kref_init(&ev_file->ref);
650 	spin_lock_init(&ev_file->lock);
651 	INIT_LIST_HEAD(&ev_file->event_list);
652 	init_waitqueue_head(&ev_file->poll_wait);
653 	ev_file->uverbs_file = uverbs_file;
654 	kref_get(&ev_file->uverbs_file->ref);
655 	ev_file->async_queue = NULL;
656 	ev_file->is_closed   = 0;
657 
658 	filp = anon_inode_getfile("[infinibandevent]", &uverbs_event_fops,
659 				  ev_file, O_RDONLY);
660 	if (IS_ERR(filp))
661 		goto err_put_refs;
662 
663 	mutex_lock(&uverbs_file->device->lists_mutex);
664 	list_add_tail(&ev_file->list,
665 		      &uverbs_file->device->uverbs_events_file_list);
666 	mutex_unlock(&uverbs_file->device->lists_mutex);
667 
668 	if (is_async) {
669 		WARN_ON(uverbs_file->async_file);
670 		uverbs_file->async_file = ev_file;
671 		kref_get(&uverbs_file->async_file->ref);
672 		INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
673 				      ib_dev,
674 				      ib_uverbs_event_handler);
675 		ret = ib_register_event_handler(&uverbs_file->event_handler);
676 		if (ret)
677 			goto err_put_file;
678 
679 		/* At that point async file stuff was fully set */
680 		ev_file->is_async = 1;
681 	}
682 
683 	return filp;
684 
685 err_put_file:
686 	fput(filp);
687 	kref_put(&uverbs_file->async_file->ref, ib_uverbs_release_event_file);
688 	uverbs_file->async_file = NULL;
689 	return ERR_PTR(ret);
690 
691 err_put_refs:
692 	kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
693 	kref_put(&ev_file->ref, ib_uverbs_release_event_file);
694 	return filp;
695 }
696 
697 /*
698  * Look up a completion event file by FD.  If lookup is successful,
699  * takes a ref to the event file struct that it returns; if
700  * unsuccessful, returns NULL.
701  */
702 struct ib_uverbs_event_file *ib_uverbs_lookup_comp_file(int fd)
703 {
704 	struct ib_uverbs_event_file *ev_file = NULL;
705 	struct fd f = fdget(fd);
706 
707 	if (!f.file)
708 		return NULL;
709 
710 	if (f.file->f_op != &uverbs_event_fops)
711 		goto out;
712 
713 	ev_file = f.file->private_data;
714 	if (ev_file->is_async) {
715 		ev_file = NULL;
716 		goto out;
717 	}
718 
719 	kref_get(&ev_file->ref);
720 
721 out:
722 	fdput(f);
723 	return ev_file;
724 }
725 
726 static int verify_command_mask(struct ib_device *ib_dev, __u32 command)
727 {
728 	u64 mask;
729 
730 	if (command <= IB_USER_VERBS_CMD_OPEN_QP)
731 		mask = ib_dev->uverbs_cmd_mask;
732 	else
733 		mask = ib_dev->uverbs_ex_cmd_mask;
734 
735 	if (mask & ((u64)1 << command))
736 		return 0;
737 
738 	return -1;
739 }
740 
741 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
742 			     size_t count, loff_t *pos)
743 {
744 	struct ib_uverbs_file *file = filp->private_data;
745 	struct ib_device *ib_dev;
746 	struct ib_uverbs_cmd_hdr hdr;
747 	__u32 command;
748 	__u32 flags;
749 	int srcu_key;
750 	ssize_t ret;
751 
752 	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
753 		return -EACCES;
754 
755 	if (count < sizeof hdr)
756 		return -EINVAL;
757 
758 	if (copy_from_user(&hdr, buf, sizeof hdr))
759 		return -EFAULT;
760 
761 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
762 	ib_dev = srcu_dereference(file->device->ib_dev,
763 				  &file->device->disassociate_srcu);
764 	if (!ib_dev) {
765 		ret = -EIO;
766 		goto out;
767 	}
768 
769 	if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
770 				   IB_USER_VERBS_CMD_COMMAND_MASK)) {
771 		ret = -EINVAL;
772 		goto out;
773 	}
774 
775 	command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
776 	if (verify_command_mask(ib_dev, command)) {
777 		ret = -EOPNOTSUPP;
778 		goto out;
779 	}
780 
781 	if (!file->ucontext &&
782 	    command != IB_USER_VERBS_CMD_GET_CONTEXT) {
783 		ret = -EINVAL;
784 		goto out;
785 	}
786 
787 	flags = (hdr.command &
788 		 IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
789 
790 	if (!flags) {
791 		if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
792 		    !uverbs_cmd_table[command]) {
793 			ret = -EINVAL;
794 			goto out;
795 		}
796 
797 		if (hdr.in_words * 4 != count) {
798 			ret = -EINVAL;
799 			goto out;
800 		}
801 
802 		ret = uverbs_cmd_table[command](file, ib_dev,
803 						 buf + sizeof(hdr),
804 						 hdr.in_words * 4,
805 						 hdr.out_words * 4);
806 
807 	} else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
808 		struct ib_uverbs_ex_cmd_hdr ex_hdr;
809 		struct ib_udata ucore;
810 		struct ib_udata uhw;
811 		size_t written_count = count;
812 
813 		if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
814 		    !uverbs_ex_cmd_table[command]) {
815 			ret = -ENOSYS;
816 			goto out;
817 		}
818 
819 		if (!file->ucontext) {
820 			ret = -EINVAL;
821 			goto out;
822 		}
823 
824 		if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
825 			ret = -EINVAL;
826 			goto out;
827 		}
828 
829 		if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
830 			ret = -EFAULT;
831 			goto out;
832 		}
833 
834 		count -= sizeof(hdr) + sizeof(ex_hdr);
835 		buf += sizeof(hdr) + sizeof(ex_hdr);
836 
837 		if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
838 			ret = -EINVAL;
839 			goto out;
840 		}
841 
842 		if (ex_hdr.cmd_hdr_reserved) {
843 			ret = -EINVAL;
844 			goto out;
845 		}
846 
847 		if (ex_hdr.response) {
848 			if (!hdr.out_words && !ex_hdr.provider_out_words) {
849 				ret = -EINVAL;
850 				goto out;
851 			}
852 
853 			if (!access_ok(VERIFY_WRITE,
854 				       (void __user *) (unsigned long) ex_hdr.response,
855 				       (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
856 				ret = -EFAULT;
857 				goto out;
858 			}
859 		} else {
860 			if (hdr.out_words || ex_hdr.provider_out_words) {
861 				ret = -EINVAL;
862 				goto out;
863 			}
864 		}
865 
866 		INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
867 				       hdr.in_words * 8, hdr.out_words * 8);
868 
869 		INIT_UDATA_BUF_OR_NULL(&uhw,
870 				       buf + ucore.inlen,
871 				       (unsigned long) ex_hdr.response + ucore.outlen,
872 				       ex_hdr.provider_in_words * 8,
873 				       ex_hdr.provider_out_words * 8);
874 
875 		ret = uverbs_ex_cmd_table[command](file,
876 						   ib_dev,
877 						   &ucore,
878 						   &uhw);
879 		if (!ret)
880 			ret = written_count;
881 	} else {
882 		ret = -ENOSYS;
883 	}
884 
885 out:
886 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
887 	return ret;
888 }
889 
890 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
891 {
892 	struct ib_uverbs_file *file = filp->private_data;
893 	struct ib_device *ib_dev;
894 	int ret = 0;
895 	int srcu_key;
896 
897 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
898 	ib_dev = srcu_dereference(file->device->ib_dev,
899 				  &file->device->disassociate_srcu);
900 	if (!ib_dev) {
901 		ret = -EIO;
902 		goto out;
903 	}
904 
905 	if (!file->ucontext)
906 		ret = -ENODEV;
907 	else
908 		ret = ib_dev->mmap(file->ucontext, vma);
909 out:
910 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
911 	return ret;
912 }
913 
914 /*
915  * ib_uverbs_open() does not need the BKL:
916  *
917  *  - the ib_uverbs_device structures are properly reference counted and
918  *    everything else is purely local to the file being created, so
919  *    races against other open calls are not a problem;
920  *  - there is no ioctl method to race against;
921  *  - the open method will either immediately run -ENXIO, or all
922  *    required initialization will be done.
923  */
924 static int ib_uverbs_open(struct inode *inode, struct file *filp)
925 {
926 	struct ib_uverbs_device *dev;
927 	struct ib_uverbs_file *file;
928 	struct ib_device *ib_dev;
929 	int ret;
930 	int module_dependent;
931 	int srcu_key;
932 
933 	dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
934 	if (!atomic_inc_not_zero(&dev->refcount))
935 		return -ENXIO;
936 
937 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
938 	mutex_lock(&dev->lists_mutex);
939 	ib_dev = srcu_dereference(dev->ib_dev,
940 				  &dev->disassociate_srcu);
941 	if (!ib_dev) {
942 		ret = -EIO;
943 		goto err;
944 	}
945 
946 	/* In case IB device supports disassociate ucontext, there is no hard
947 	 * dependency between uverbs device and its low level device.
948 	 */
949 	module_dependent = !(ib_dev->disassociate_ucontext);
950 
951 	if (module_dependent) {
952 		if (!try_module_get(ib_dev->owner)) {
953 			ret = -ENODEV;
954 			goto err;
955 		}
956 	}
957 
958 	file = kzalloc(sizeof(*file), GFP_KERNEL);
959 	if (!file) {
960 		ret = -ENOMEM;
961 		if (module_dependent)
962 			goto err_module;
963 
964 		goto err;
965 	}
966 
967 	file->device	 = dev;
968 	file->ucontext	 = NULL;
969 	file->async_file = NULL;
970 	kref_init(&file->ref);
971 	mutex_init(&file->mutex);
972 	mutex_init(&file->cleanup_mutex);
973 
974 	filp->private_data = file;
975 	kobject_get(&dev->kobj);
976 	list_add_tail(&file->list, &dev->uverbs_file_list);
977 	mutex_unlock(&dev->lists_mutex);
978 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
979 
980 	return nonseekable_open(inode, filp);
981 
982 err_module:
983 	module_put(ib_dev->owner);
984 
985 err:
986 	mutex_unlock(&dev->lists_mutex);
987 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
988 	if (atomic_dec_and_test(&dev->refcount))
989 		ib_uverbs_comp_dev(dev);
990 
991 	return ret;
992 }
993 
994 static int ib_uverbs_close(struct inode *inode, struct file *filp)
995 {
996 	struct ib_uverbs_file *file = filp->private_data;
997 	struct ib_uverbs_device *dev = file->device;
998 
999 	mutex_lock(&file->cleanup_mutex);
1000 	if (file->ucontext) {
1001 		ib_uverbs_cleanup_ucontext(file, file->ucontext);
1002 		file->ucontext = NULL;
1003 	}
1004 	mutex_unlock(&file->cleanup_mutex);
1005 
1006 	mutex_lock(&file->device->lists_mutex);
1007 	if (!file->is_closed) {
1008 		list_del(&file->list);
1009 		file->is_closed = 1;
1010 	}
1011 	mutex_unlock(&file->device->lists_mutex);
1012 
1013 	if (file->async_file)
1014 		kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
1015 
1016 	kref_put(&file->ref, ib_uverbs_release_file);
1017 	kobject_put(&dev->kobj);
1018 
1019 	return 0;
1020 }
1021 
1022 static const struct file_operations uverbs_fops = {
1023 	.owner	 = THIS_MODULE,
1024 	.write	 = ib_uverbs_write,
1025 	.open	 = ib_uverbs_open,
1026 	.release = ib_uverbs_close,
1027 	.llseek	 = no_llseek,
1028 };
1029 
1030 static const struct file_operations uverbs_mmap_fops = {
1031 	.owner	 = THIS_MODULE,
1032 	.write	 = ib_uverbs_write,
1033 	.mmap    = ib_uverbs_mmap,
1034 	.open	 = ib_uverbs_open,
1035 	.release = ib_uverbs_close,
1036 	.llseek	 = no_llseek,
1037 };
1038 
1039 static struct ib_client uverbs_client = {
1040 	.name   = "uverbs",
1041 	.add    = ib_uverbs_add_one,
1042 	.remove = ib_uverbs_remove_one
1043 };
1044 
1045 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
1046 			  char *buf)
1047 {
1048 	int ret = -ENODEV;
1049 	int srcu_key;
1050 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
1051 	struct ib_device *ib_dev;
1052 
1053 	if (!dev)
1054 		return -ENODEV;
1055 
1056 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1057 	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1058 	if (ib_dev)
1059 		ret = sprintf(buf, "%s\n", ib_dev->name);
1060 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1061 
1062 	return ret;
1063 }
1064 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1065 
1066 static ssize_t show_dev_abi_version(struct device *device,
1067 				    struct device_attribute *attr, char *buf)
1068 {
1069 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
1070 	int ret = -ENODEV;
1071 	int srcu_key;
1072 	struct ib_device *ib_dev;
1073 
1074 	if (!dev)
1075 		return -ENODEV;
1076 	srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1077 	ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1078 	if (ib_dev)
1079 		ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1080 	srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1081 
1082 	return ret;
1083 }
1084 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1085 
1086 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1087 			 __stringify(IB_USER_VERBS_ABI_VERSION));
1088 
1089 static dev_t overflow_maj;
1090 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
1091 
1092 /*
1093  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
1094  * requesting a new major number and doubling the number of max devices we
1095  * support. It's stupid, but simple.
1096  */
1097 static int find_overflow_devnum(void)
1098 {
1099 	int ret;
1100 
1101 	if (!overflow_maj) {
1102 		ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
1103 					  "infiniband_verbs");
1104 		if (ret) {
1105 			pr_err("user_verbs: couldn't register dynamic device number\n");
1106 			return ret;
1107 		}
1108 	}
1109 
1110 	ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
1111 	if (ret >= IB_UVERBS_MAX_DEVICES)
1112 		return -1;
1113 
1114 	return ret;
1115 }
1116 
1117 static void ib_uverbs_add_one(struct ib_device *device)
1118 {
1119 	int devnum;
1120 	dev_t base;
1121 	struct ib_uverbs_device *uverbs_dev;
1122 	int ret;
1123 
1124 	if (!device->alloc_ucontext)
1125 		return;
1126 
1127 	uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1128 	if (!uverbs_dev)
1129 		return;
1130 
1131 	ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1132 	if (ret) {
1133 		kfree(uverbs_dev);
1134 		return;
1135 	}
1136 
1137 	atomic_set(&uverbs_dev->refcount, 1);
1138 	init_completion(&uverbs_dev->comp);
1139 	uverbs_dev->xrcd_tree = RB_ROOT;
1140 	mutex_init(&uverbs_dev->xrcd_tree_mutex);
1141 	kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1142 	mutex_init(&uverbs_dev->lists_mutex);
1143 	INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1144 	INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1145 
1146 	spin_lock(&map_lock);
1147 	devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1148 	if (devnum >= IB_UVERBS_MAX_DEVICES) {
1149 		spin_unlock(&map_lock);
1150 		devnum = find_overflow_devnum();
1151 		if (devnum < 0)
1152 			goto err;
1153 
1154 		spin_lock(&map_lock);
1155 		uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
1156 		base = devnum + overflow_maj;
1157 		set_bit(devnum, overflow_map);
1158 	} else {
1159 		uverbs_dev->devnum = devnum;
1160 		base = devnum + IB_UVERBS_BASE_DEV;
1161 		set_bit(devnum, dev_map);
1162 	}
1163 	spin_unlock(&map_lock);
1164 
1165 	rcu_assign_pointer(uverbs_dev->ib_dev, device);
1166 	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1167 
1168 	cdev_init(&uverbs_dev->cdev, NULL);
1169 	uverbs_dev->cdev.owner = THIS_MODULE;
1170 	uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1171 	uverbs_dev->cdev.kobj.parent = &uverbs_dev->kobj;
1172 	kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1173 	if (cdev_add(&uverbs_dev->cdev, base, 1))
1174 		goto err_cdev;
1175 
1176 	uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
1177 					uverbs_dev->cdev.dev, uverbs_dev,
1178 					"uverbs%d", uverbs_dev->devnum);
1179 	if (IS_ERR(uverbs_dev->dev))
1180 		goto err_cdev;
1181 
1182 	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1183 		goto err_class;
1184 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1185 		goto err_class;
1186 
1187 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
1188 
1189 	return;
1190 
1191 err_class:
1192 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1193 
1194 err_cdev:
1195 	cdev_del(&uverbs_dev->cdev);
1196 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1197 		clear_bit(devnum, dev_map);
1198 	else
1199 		clear_bit(devnum, overflow_map);
1200 
1201 err:
1202 	if (atomic_dec_and_test(&uverbs_dev->refcount))
1203 		ib_uverbs_comp_dev(uverbs_dev);
1204 	wait_for_completion(&uverbs_dev->comp);
1205 	kobject_put(&uverbs_dev->kobj);
1206 	return;
1207 }
1208 
1209 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1210 					struct ib_device *ib_dev)
1211 {
1212 	struct ib_uverbs_file *file;
1213 	struct ib_uverbs_event_file *event_file;
1214 	struct ib_event event;
1215 
1216 	/* Pending running commands to terminate */
1217 	synchronize_srcu(&uverbs_dev->disassociate_srcu);
1218 	event.event = IB_EVENT_DEVICE_FATAL;
1219 	event.element.port_num = 0;
1220 	event.device = ib_dev;
1221 
1222 	mutex_lock(&uverbs_dev->lists_mutex);
1223 	while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1224 		struct ib_ucontext *ucontext;
1225 		file = list_first_entry(&uverbs_dev->uverbs_file_list,
1226 					struct ib_uverbs_file, list);
1227 		file->is_closed = 1;
1228 		list_del(&file->list);
1229 		kref_get(&file->ref);
1230 		mutex_unlock(&uverbs_dev->lists_mutex);
1231 
1232 		ib_uverbs_event_handler(&file->event_handler, &event);
1233 
1234 		mutex_lock(&file->cleanup_mutex);
1235 		ucontext = file->ucontext;
1236 		file->ucontext = NULL;
1237 		mutex_unlock(&file->cleanup_mutex);
1238 
1239 		/* At this point ib_uverbs_close cannot be running
1240 		 * ib_uverbs_cleanup_ucontext
1241 		 */
1242 		if (ucontext) {
1243 			/* We must release the mutex before going ahead and
1244 			 * calling disassociate_ucontext. disassociate_ucontext
1245 			 * might end up indirectly calling uverbs_close,
1246 			 * for example due to freeing the resources
1247 			 * (e.g mmput).
1248 			 */
1249 			ib_dev->disassociate_ucontext(ucontext);
1250 			ib_uverbs_cleanup_ucontext(file, ucontext);
1251 		}
1252 
1253 		mutex_lock(&uverbs_dev->lists_mutex);
1254 		kref_put(&file->ref, ib_uverbs_release_file);
1255 	}
1256 
1257 	while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1258 		event_file = list_first_entry(&uverbs_dev->
1259 					      uverbs_events_file_list,
1260 					      struct ib_uverbs_event_file,
1261 					      list);
1262 		spin_lock_irq(&event_file->lock);
1263 		event_file->is_closed = 1;
1264 		spin_unlock_irq(&event_file->lock);
1265 
1266 		list_del(&event_file->list);
1267 		if (event_file->is_async) {
1268 			ib_unregister_event_handler(&event_file->uverbs_file->
1269 						    event_handler);
1270 			event_file->uverbs_file->event_handler.device = NULL;
1271 		}
1272 
1273 		wake_up_interruptible(&event_file->poll_wait);
1274 		kill_fasync(&event_file->async_queue, SIGIO, POLL_IN);
1275 	}
1276 	mutex_unlock(&uverbs_dev->lists_mutex);
1277 }
1278 
1279 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1280 {
1281 	struct ib_uverbs_device *uverbs_dev = client_data;
1282 	int wait_clients = 1;
1283 
1284 	if (!uverbs_dev)
1285 		return;
1286 
1287 	dev_set_drvdata(uverbs_dev->dev, NULL);
1288 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1289 	cdev_del(&uverbs_dev->cdev);
1290 
1291 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1292 		clear_bit(uverbs_dev->devnum, dev_map);
1293 	else
1294 		clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
1295 
1296 	if (device->disassociate_ucontext) {
1297 		/* We disassociate HW resources and immediately return.
1298 		 * Userspace will see a EIO errno for all future access.
1299 		 * Upon returning, ib_device may be freed internally and is not
1300 		 * valid any more.
1301 		 * uverbs_device is still available until all clients close
1302 		 * their files, then the uverbs device ref count will be zero
1303 		 * and its resources will be freed.
1304 		 * Note: At this point no more files can be opened since the
1305 		 * cdev was deleted, however active clients can still issue
1306 		 * commands and close their open files.
1307 		 */
1308 		rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1309 		ib_uverbs_free_hw_resources(uverbs_dev, device);
1310 		wait_clients = 0;
1311 	}
1312 
1313 	if (atomic_dec_and_test(&uverbs_dev->refcount))
1314 		ib_uverbs_comp_dev(uverbs_dev);
1315 	if (wait_clients)
1316 		wait_for_completion(&uverbs_dev->comp);
1317 	kobject_put(&uverbs_dev->kobj);
1318 }
1319 
1320 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1321 {
1322 	if (mode)
1323 		*mode = 0666;
1324 	return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1325 }
1326 
1327 static int __init ib_uverbs_init(void)
1328 {
1329 	int ret;
1330 
1331 	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
1332 				     "infiniband_verbs");
1333 	if (ret) {
1334 		pr_err("user_verbs: couldn't register device number\n");
1335 		goto out;
1336 	}
1337 
1338 	uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1339 	if (IS_ERR(uverbs_class)) {
1340 		ret = PTR_ERR(uverbs_class);
1341 		pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1342 		goto out_chrdev;
1343 	}
1344 
1345 	uverbs_class->devnode = uverbs_devnode;
1346 
1347 	ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1348 	if (ret) {
1349 		pr_err("user_verbs: couldn't create abi_version attribute\n");
1350 		goto out_class;
1351 	}
1352 
1353 	ret = ib_register_client(&uverbs_client);
1354 	if (ret) {
1355 		pr_err("user_verbs: couldn't register client\n");
1356 		goto out_class;
1357 	}
1358 
1359 	return 0;
1360 
1361 out_class:
1362 	class_destroy(uverbs_class);
1363 
1364 out_chrdev:
1365 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1366 
1367 out:
1368 	return ret;
1369 }
1370 
1371 static void __exit ib_uverbs_cleanup(void)
1372 {
1373 	ib_unregister_client(&uverbs_client);
1374 	class_destroy(uverbs_class);
1375 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1376 	if (overflow_maj)
1377 		unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1378 	idr_destroy(&ib_uverbs_pd_idr);
1379 	idr_destroy(&ib_uverbs_mr_idr);
1380 	idr_destroy(&ib_uverbs_mw_idr);
1381 	idr_destroy(&ib_uverbs_ah_idr);
1382 	idr_destroy(&ib_uverbs_cq_idr);
1383 	idr_destroy(&ib_uverbs_qp_idr);
1384 	idr_destroy(&ib_uverbs_srq_idr);
1385 }
1386 
1387 module_init(ib_uverbs_init);
1388 module_exit(ib_uverbs_cleanup);
1389