Merge tag 'topic/drm-misc-2016-02-08' of git://anongit.freedesktop.org/drm-intel...
[cascardo/linux.git] / drivers / infiniband / core / uverbs_main.c
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);