xref: /linux/drivers/infiniband/core/uverbs_main.c (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
1 /*
2  * Copyright (c) 2005 Topspin Communications.  All rights reserved.
3  * Copyright (c) 2005 Cisco Systems.  All rights reserved.
4  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
5  * Copyright (c) 2005 Voltaire, Inc. All rights reserved.
6  *
7  * This software is available to you under a choice of one of two
8  * licenses.  You may choose to be licensed under the terms of the GNU
9  * General Public License (GPL) Version 2, available from the file
10  * COPYING in the main directory of this source tree, or the
11  * OpenIB.org BSD license below:
12  *
13  *     Redistribution and use in source and binary forms, with or
14  *     without modification, are permitted provided that the following
15  *     conditions are met:
16  *
17  *      - Redistributions of source code must retain the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer.
20  *
21  *      - Redistributions in binary form must reproduce the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer in the documentation and/or other materials
24  *        provided with the distribution.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33  * SOFTWARE.
34  *
35  * $Id: uverbs_main.c 2733 2005-06-28 19:14:34Z roland $
36  */
37 
38 #include <linux/module.h>
39 #include <linux/init.h>
40 #include <linux/device.h>
41 #include <linux/err.h>
42 #include <linux/fs.h>
43 #include <linux/poll.h>
44 #include <linux/file.h>
45 #include <linux/mount.h>
46 
47 #include <asm/uaccess.h>
48 
49 #include "uverbs.h"
50 
51 MODULE_AUTHOR("Roland Dreier");
52 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
53 MODULE_LICENSE("Dual BSD/GPL");
54 
55 #define INFINIBANDEVENTFS_MAGIC	0x49426576	/* "IBev" */
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 DECLARE_MUTEX(ib_uverbs_idr_mutex);
66 DEFINE_IDR(ib_uverbs_pd_idr);
67 DEFINE_IDR(ib_uverbs_mr_idr);
68 DEFINE_IDR(ib_uverbs_mw_idr);
69 DEFINE_IDR(ib_uverbs_ah_idr);
70 DEFINE_IDR(ib_uverbs_cq_idr);
71 DEFINE_IDR(ib_uverbs_qp_idr);
72 DEFINE_IDR(ib_uverbs_srq_idr);
73 
74 static spinlock_t map_lock;
75 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
76 
77 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
78 				     const char __user *buf, int in_len,
79 				     int out_len) = {
80 	[IB_USER_VERBS_CMD_QUERY_PARAMS]  = ib_uverbs_query_params,
81 	[IB_USER_VERBS_CMD_GET_CONTEXT]   = ib_uverbs_get_context,
82 	[IB_USER_VERBS_CMD_QUERY_DEVICE]  = ib_uverbs_query_device,
83 	[IB_USER_VERBS_CMD_QUERY_PORT]    = ib_uverbs_query_port,
84 	[IB_USER_VERBS_CMD_QUERY_GID]     = ib_uverbs_query_gid,
85 	[IB_USER_VERBS_CMD_QUERY_PKEY]    = ib_uverbs_query_pkey,
86 	[IB_USER_VERBS_CMD_ALLOC_PD]      = ib_uverbs_alloc_pd,
87 	[IB_USER_VERBS_CMD_DEALLOC_PD]    = ib_uverbs_dealloc_pd,
88 	[IB_USER_VERBS_CMD_REG_MR]        = ib_uverbs_reg_mr,
89 	[IB_USER_VERBS_CMD_DEREG_MR]      = ib_uverbs_dereg_mr,
90 	[IB_USER_VERBS_CMD_CREATE_CQ]     = ib_uverbs_create_cq,
91 	[IB_USER_VERBS_CMD_DESTROY_CQ]    = ib_uverbs_destroy_cq,
92 	[IB_USER_VERBS_CMD_CREATE_QP]     = ib_uverbs_create_qp,
93 	[IB_USER_VERBS_CMD_MODIFY_QP]     = ib_uverbs_modify_qp,
94 	[IB_USER_VERBS_CMD_DESTROY_QP]    = ib_uverbs_destroy_qp,
95 	[IB_USER_VERBS_CMD_ATTACH_MCAST]  = ib_uverbs_attach_mcast,
96 	[IB_USER_VERBS_CMD_DETACH_MCAST]  = ib_uverbs_detach_mcast,
97 	[IB_USER_VERBS_CMD_CREATE_SRQ]    = ib_uverbs_create_srq,
98 	[IB_USER_VERBS_CMD_MODIFY_SRQ]    = ib_uverbs_modify_srq,
99 	[IB_USER_VERBS_CMD_DESTROY_SRQ]   = ib_uverbs_destroy_srq,
100 };
101 
102 static struct vfsmount *uverbs_event_mnt;
103 
104 static void ib_uverbs_add_one(struct ib_device *device);
105 static void ib_uverbs_remove_one(struct ib_device *device);
106 
107 static int ib_dealloc_ucontext(struct ib_ucontext *context)
108 {
109 	struct ib_uobject *uobj, *tmp;
110 
111 	if (!context)
112 		return 0;
113 
114 	down(&ib_uverbs_idr_mutex);
115 
116 	/* XXX Free AHs */
117 
118 	list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {
119 		struct ib_qp *qp = idr_find(&ib_uverbs_qp_idr, uobj->id);
120 		idr_remove(&ib_uverbs_qp_idr, uobj->id);
121 		ib_destroy_qp(qp);
122 		list_del(&uobj->list);
123 		kfree(container_of(uobj, struct ib_uevent_object, uobject));
124 	}
125 
126 	list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {
127 		struct ib_cq *cq = idr_find(&ib_uverbs_cq_idr, uobj->id);
128 		idr_remove(&ib_uverbs_cq_idr, uobj->id);
129 		ib_destroy_cq(cq);
130 		list_del(&uobj->list);
131 		kfree(container_of(uobj, struct ib_ucq_object, uobject));
132 	}
133 
134 	list_for_each_entry_safe(uobj, tmp, &context->srq_list, list) {
135 		struct ib_srq *srq = idr_find(&ib_uverbs_srq_idr, uobj->id);
136 		idr_remove(&ib_uverbs_srq_idr, uobj->id);
137 		ib_destroy_srq(srq);
138 		list_del(&uobj->list);
139 		kfree(container_of(uobj, struct ib_uevent_object, uobject));
140 	}
141 
142 	/* XXX Free MWs */
143 
144 	list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {
145 		struct ib_mr *mr = idr_find(&ib_uverbs_mr_idr, uobj->id);
146 		struct ib_device *mrdev = mr->device;
147 		struct ib_umem_object *memobj;
148 
149 		idr_remove(&ib_uverbs_mr_idr, uobj->id);
150 		ib_dereg_mr(mr);
151 
152 		memobj = container_of(uobj, struct ib_umem_object, uobject);
153 		ib_umem_release_on_close(mrdev, &memobj->umem);
154 
155 		list_del(&uobj->list);
156 		kfree(memobj);
157 	}
158 
159 	list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
160 		struct ib_pd *pd = idr_find(&ib_uverbs_pd_idr, uobj->id);
161 		idr_remove(&ib_uverbs_pd_idr, uobj->id);
162 		ib_dealloc_pd(pd);
163 		list_del(&uobj->list);
164 		kfree(uobj);
165 	}
166 
167 	up(&ib_uverbs_idr_mutex);
168 
169 	return context->device->dealloc_ucontext(context);
170 }
171 
172 static void ib_uverbs_release_file(struct kref *ref)
173 {
174 	struct ib_uverbs_file *file =
175 		container_of(ref, struct ib_uverbs_file, ref);
176 
177 	module_put(file->device->ib_dev->owner);
178 	kfree(file);
179 }
180 
181 static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,
182 				    size_t count, loff_t *pos)
183 {
184 	struct ib_uverbs_event_file *file = filp->private_data;
185 	struct ib_uverbs_event *event;
186 	int eventsz;
187 	int ret = 0;
188 
189 	spin_lock_irq(&file->lock);
190 
191 	while (list_empty(&file->event_list) && file->fd >= 0) {
192 		spin_unlock_irq(&file->lock);
193 
194 		if (filp->f_flags & O_NONBLOCK)
195 			return -EAGAIN;
196 
197 		if (wait_event_interruptible(file->poll_wait,
198 					     !list_empty(&file->event_list) ||
199 					     file->fd < 0))
200 			return -ERESTARTSYS;
201 
202 		spin_lock_irq(&file->lock);
203 	}
204 
205 	if (file->fd < 0) {
206 		spin_unlock_irq(&file->lock);
207 		return -ENODEV;
208 	}
209 
210 	event = list_entry(file->event_list.next, struct ib_uverbs_event, list);
211 
212 	if (file->is_async)
213 		eventsz = sizeof (struct ib_uverbs_async_event_desc);
214 	else
215 		eventsz = sizeof (struct ib_uverbs_comp_event_desc);
216 
217 	if (eventsz > count) {
218 		ret   = -EINVAL;
219 		event = NULL;
220 	} else {
221 		list_del(file->event_list.next);
222 		if (event->counter) {
223 			++(*event->counter);
224 			list_del(&event->obj_list);
225 		}
226 	}
227 
228 	spin_unlock_irq(&file->lock);
229 
230 	if (event) {
231 		if (copy_to_user(buf, event, eventsz))
232 			ret = -EFAULT;
233 		else
234 			ret = eventsz;
235 	}
236 
237 	kfree(event);
238 
239 	return ret;
240 }
241 
242 static unsigned int ib_uverbs_event_poll(struct file *filp,
243 					 struct poll_table_struct *wait)
244 {
245 	unsigned int pollflags = 0;
246 	struct ib_uverbs_event_file *file = filp->private_data;
247 
248 	poll_wait(filp, &file->poll_wait, wait);
249 
250 	spin_lock_irq(&file->lock);
251 	if (file->fd < 0)
252 		pollflags = POLLERR;
253 	else if (!list_empty(&file->event_list))
254 		pollflags = POLLIN | POLLRDNORM;
255 	spin_unlock_irq(&file->lock);
256 
257 	return pollflags;
258 }
259 
260 static void ib_uverbs_event_release(struct ib_uverbs_event_file *file)
261 {
262 	struct ib_uverbs_event *entry, *tmp;
263 
264 	spin_lock_irq(&file->lock);
265 	if (file->fd != -1) {
266 		file->fd = -1;
267 		list_for_each_entry_safe(entry, tmp, &file->event_list, list)
268 			kfree(entry);
269 	}
270 	spin_unlock_irq(&file->lock);
271 }
272 
273 static int ib_uverbs_event_fasync(int fd, struct file *filp, int on)
274 {
275 	struct ib_uverbs_event_file *file = filp->private_data;
276 
277 	return fasync_helper(fd, filp, on, &file->async_queue);
278 }
279 
280 static int ib_uverbs_event_close(struct inode *inode, struct file *filp)
281 {
282 	struct ib_uverbs_event_file *file = filp->private_data;
283 
284 	ib_uverbs_event_release(file);
285 	ib_uverbs_event_fasync(-1, filp, 0);
286 	kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);
287 
288 	return 0;
289 }
290 
291 static struct file_operations uverbs_event_fops = {
292 	/*
293 	 * No .owner field since we artificially create event files,
294 	 * so there is no increment to the module reference count in
295 	 * the open path.  All event files come from a uverbs command
296 	 * file, which already takes a module reference, so this is OK.
297 	 */
298 	.read 	 = ib_uverbs_event_read,
299 	.poll    = ib_uverbs_event_poll,
300 	.release = ib_uverbs_event_close,
301 	.fasync  = ib_uverbs_event_fasync
302 };
303 
304 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
305 {
306 	struct ib_uverbs_file  *file = cq_context;
307 	struct ib_ucq_object   *uobj;
308 	struct ib_uverbs_event *entry;
309 	unsigned long           flags;
310 
311 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
312 	if (!entry)
313 		return;
314 
315 	uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
316 
317 	entry->desc.comp.cq_handle = cq->uobject->user_handle;
318 	entry->counter		   = &uobj->comp_events_reported;
319 
320 	spin_lock_irqsave(&file->comp_file[0].lock, flags);
321 	list_add_tail(&entry->list, &file->comp_file[0].event_list);
322 	list_add_tail(&entry->obj_list, &uobj->comp_list);
323 	spin_unlock_irqrestore(&file->comp_file[0].lock, flags);
324 
325 	wake_up_interruptible(&file->comp_file[0].poll_wait);
326 	kill_fasync(&file->comp_file[0].async_queue, SIGIO, POLL_IN);
327 }
328 
329 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
330 				    __u64 element, __u64 event,
331 				    struct list_head *obj_list,
332 				    u32 *counter)
333 {
334 	struct ib_uverbs_event *entry;
335 	unsigned long flags;
336 
337 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
338 	if (!entry)
339 		return;
340 
341 	entry->desc.async.element    = element;
342 	entry->desc.async.event_type = event;
343 	entry->counter               = counter;
344 
345 	spin_lock_irqsave(&file->async_file.lock, flags);
346 	list_add_tail(&entry->list, &file->async_file.event_list);
347 	if (obj_list)
348 		list_add_tail(&entry->obj_list, obj_list);
349 	spin_unlock_irqrestore(&file->async_file.lock, flags);
350 
351 	wake_up_interruptible(&file->async_file.poll_wait);
352 	kill_fasync(&file->async_file.async_queue, SIGIO, POLL_IN);
353 }
354 
355 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
356 {
357 	struct ib_ucq_object *uobj;
358 
359 	uobj = container_of(event->element.cq->uobject,
360 			    struct ib_ucq_object, uobject);
361 
362 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
363 				event->event, &uobj->async_list,
364 				&uobj->async_events_reported);
365 
366 }
367 
368 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
369 {
370 	struct ib_uevent_object *uobj;
371 
372 	uobj = container_of(event->element.qp->uobject,
373 			    struct ib_uevent_object, uobject);
374 
375 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
376 				event->event, &uobj->event_list,
377 				&uobj->events_reported);
378 }
379 
380 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
381 {
382 	struct ib_uevent_object *uobj;
383 
384 	uobj = container_of(event->element.srq->uobject,
385 			    struct ib_uevent_object, uobject);
386 
387 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
388 				event->event, &uobj->event_list,
389 				&uobj->events_reported);
390 }
391 
392 static void ib_uverbs_event_handler(struct ib_event_handler *handler,
393 				    struct ib_event *event)
394 {
395 	struct ib_uverbs_file *file =
396 		container_of(handler, struct ib_uverbs_file, event_handler);
397 
398 	ib_uverbs_async_handler(file, event->element.port_num, event->event,
399 				NULL, NULL);
400 }
401 
402 static int ib_uverbs_event_init(struct ib_uverbs_event_file *file,
403 				struct ib_uverbs_file *uverbs_file)
404 {
405 	struct file *filp;
406 
407 	spin_lock_init(&file->lock);
408 	INIT_LIST_HEAD(&file->event_list);
409 	init_waitqueue_head(&file->poll_wait);
410 	file->uverbs_file = uverbs_file;
411 	file->async_queue = NULL;
412 
413 	file->fd = get_unused_fd();
414 	if (file->fd < 0)
415 		return file->fd;
416 
417 	filp = get_empty_filp();
418 	if (!filp) {
419 		put_unused_fd(file->fd);
420 		return -ENFILE;
421 	}
422 
423 	filp->f_op 	   = &uverbs_event_fops;
424 	filp->f_vfsmnt 	   = mntget(uverbs_event_mnt);
425 	filp->f_dentry 	   = dget(uverbs_event_mnt->mnt_root);
426 	filp->f_mapping    = filp->f_dentry->d_inode->i_mapping;
427 	filp->f_flags      = O_RDONLY;
428 	filp->f_mode       = FMODE_READ;
429 	filp->private_data = file;
430 
431 	fd_install(file->fd, filp);
432 
433 	return 0;
434 }
435 
436 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
437 			     size_t count, loff_t *pos)
438 {
439 	struct ib_uverbs_file *file = filp->private_data;
440 	struct ib_uverbs_cmd_hdr hdr;
441 
442 	if (count < sizeof hdr)
443 		return -EINVAL;
444 
445 	if (copy_from_user(&hdr, buf, sizeof hdr))
446 		return -EFAULT;
447 
448 	if (hdr.in_words * 4 != count)
449 		return -EINVAL;
450 
451 	if (hdr.command < 0				||
452 	    hdr.command >= ARRAY_SIZE(uverbs_cmd_table) ||
453 	    !uverbs_cmd_table[hdr.command])
454 		return -EINVAL;
455 
456 	if (!file->ucontext                               &&
457 	    hdr.command != IB_USER_VERBS_CMD_QUERY_PARAMS &&
458 	    hdr.command != IB_USER_VERBS_CMD_GET_CONTEXT)
459 		return -EINVAL;
460 
461 	return uverbs_cmd_table[hdr.command](file, buf + sizeof hdr,
462 					     hdr.in_words * 4, hdr.out_words * 4);
463 }
464 
465 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
466 {
467 	struct ib_uverbs_file *file = filp->private_data;
468 
469 	if (!file->ucontext)
470 		return -ENODEV;
471 	else
472 		return file->device->ib_dev->mmap(file->ucontext, vma);
473 }
474 
475 static int ib_uverbs_open(struct inode *inode, struct file *filp)
476 {
477 	struct ib_uverbs_device *dev =
478 		container_of(inode->i_cdev, struct ib_uverbs_device, dev);
479 	struct ib_uverbs_file *file;
480 	int i = 0;
481 	int ret;
482 
483 	if (!try_module_get(dev->ib_dev->owner))
484 		return -ENODEV;
485 
486 	file = kmalloc(sizeof *file +
487 		       (dev->num_comp - 1) * sizeof (struct ib_uverbs_event_file),
488 		       GFP_KERNEL);
489 	if (!file) {
490 		ret = -ENOMEM;
491 		goto err;
492 	}
493 
494 	file->device = dev;
495 	kref_init(&file->ref);
496 	init_MUTEX(&file->mutex);
497 
498 	file->ucontext = NULL;
499 
500 	kref_get(&file->ref);
501 	ret = ib_uverbs_event_init(&file->async_file, file);
502 	if (ret)
503 		goto err_kref;
504 
505 	file->async_file.is_async = 1;
506 
507 	for (i = 0; i < dev->num_comp; ++i) {
508 		kref_get(&file->ref);
509 		ret = ib_uverbs_event_init(&file->comp_file[i], file);
510 		if (ret)
511 			goto err_async;
512 		file->comp_file[i].is_async = 0;
513 	}
514 
515 
516 	filp->private_data = file;
517 
518 	INIT_IB_EVENT_HANDLER(&file->event_handler, dev->ib_dev,
519 			      ib_uverbs_event_handler);
520 	if (ib_register_event_handler(&file->event_handler))
521 		goto err_async;
522 
523 	return 0;
524 
525 err_async:
526 	while (i--)
527 		ib_uverbs_event_release(&file->comp_file[i]);
528 
529 	ib_uverbs_event_release(&file->async_file);
530 
531 err_kref:
532 	/*
533 	 * One extra kref_put() because we took a reference before the
534 	 * event file creation that failed and got us here.
535 	 */
536 	kref_put(&file->ref, ib_uverbs_release_file);
537 	kref_put(&file->ref, ib_uverbs_release_file);
538 
539 err:
540 	module_put(dev->ib_dev->owner);
541 	return ret;
542 }
543 
544 static int ib_uverbs_close(struct inode *inode, struct file *filp)
545 {
546 	struct ib_uverbs_file *file = filp->private_data;
547 	int i;
548 
549 	ib_unregister_event_handler(&file->event_handler);
550 	ib_uverbs_event_release(&file->async_file);
551 	ib_dealloc_ucontext(file->ucontext);
552 
553 	for (i = 0; i < file->device->num_comp; ++i)
554 		ib_uverbs_event_release(&file->comp_file[i]);
555 
556 	kref_put(&file->ref, ib_uverbs_release_file);
557 
558 	return 0;
559 }
560 
561 static struct file_operations uverbs_fops = {
562 	.owner 	 = THIS_MODULE,
563 	.write 	 = ib_uverbs_write,
564 	.open 	 = ib_uverbs_open,
565 	.release = ib_uverbs_close
566 };
567 
568 static struct file_operations uverbs_mmap_fops = {
569 	.owner 	 = THIS_MODULE,
570 	.write 	 = ib_uverbs_write,
571 	.mmap    = ib_uverbs_mmap,
572 	.open 	 = ib_uverbs_open,
573 	.release = ib_uverbs_close
574 };
575 
576 static struct ib_client uverbs_client = {
577 	.name   = "uverbs",
578 	.add    = ib_uverbs_add_one,
579 	.remove = ib_uverbs_remove_one
580 };
581 
582 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
583 {
584 	struct ib_uverbs_device *dev =
585 		container_of(class_dev, struct ib_uverbs_device, class_dev);
586 
587 	return sprintf(buf, "%s\n", dev->ib_dev->name);
588 }
589 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
590 
591 static void ib_uverbs_release_class_dev(struct class_device *class_dev)
592 {
593 	struct ib_uverbs_device *dev =
594 		container_of(class_dev, struct ib_uverbs_device, class_dev);
595 
596 	cdev_del(&dev->dev);
597 	clear_bit(dev->devnum, dev_map);
598 	kfree(dev);
599 }
600 
601 static struct class uverbs_class = {
602 	.name    = "infiniband_verbs",
603 	.release = ib_uverbs_release_class_dev
604 };
605 
606 static ssize_t show_abi_version(struct class *class, char *buf)
607 {
608 	return sprintf(buf, "%d\n", IB_USER_VERBS_ABI_VERSION);
609 }
610 static CLASS_ATTR(abi_version, S_IRUGO, show_abi_version, NULL);
611 
612 static void ib_uverbs_add_one(struct ib_device *device)
613 {
614 	struct ib_uverbs_device *uverbs_dev;
615 
616 	if (!device->alloc_ucontext)
617 		return;
618 
619 	uverbs_dev = kmalloc(sizeof *uverbs_dev, GFP_KERNEL);
620 	if (!uverbs_dev)
621 		return;
622 
623 	memset(uverbs_dev, 0, sizeof *uverbs_dev);
624 
625 	spin_lock(&map_lock);
626 	uverbs_dev->devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
627 	if (uverbs_dev->devnum >= IB_UVERBS_MAX_DEVICES) {
628 		spin_unlock(&map_lock);
629 		goto err;
630 	}
631 	set_bit(uverbs_dev->devnum, dev_map);
632 	spin_unlock(&map_lock);
633 
634 	uverbs_dev->ib_dev   = device;
635 	uverbs_dev->num_comp = 1;
636 
637 	if (device->mmap)
638 		cdev_init(&uverbs_dev->dev, &uverbs_mmap_fops);
639 	else
640 		cdev_init(&uverbs_dev->dev, &uverbs_fops);
641 	uverbs_dev->dev.owner = THIS_MODULE;
642 	kobject_set_name(&uverbs_dev->dev.kobj, "uverbs%d", uverbs_dev->devnum);
643 	if (cdev_add(&uverbs_dev->dev, IB_UVERBS_BASE_DEV + uverbs_dev->devnum, 1))
644 		goto err;
645 
646 	uverbs_dev->class_dev.class = &uverbs_class;
647 	uverbs_dev->class_dev.dev   = device->dma_device;
648 	uverbs_dev->class_dev.devt  = uverbs_dev->dev.dev;
649 	snprintf(uverbs_dev->class_dev.class_id, BUS_ID_SIZE, "uverbs%d", uverbs_dev->devnum);
650 	if (class_device_register(&uverbs_dev->class_dev))
651 		goto err_cdev;
652 
653 	if (class_device_create_file(&uverbs_dev->class_dev, &class_device_attr_ibdev))
654 		goto err_class;
655 
656 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
657 
658 	return;
659 
660 err_class:
661 	class_device_unregister(&uverbs_dev->class_dev);
662 
663 err_cdev:
664 	cdev_del(&uverbs_dev->dev);
665 	clear_bit(uverbs_dev->devnum, dev_map);
666 
667 err:
668 	kfree(uverbs_dev);
669 	return;
670 }
671 
672 static void ib_uverbs_remove_one(struct ib_device *device)
673 {
674 	struct ib_uverbs_device *uverbs_dev = ib_get_client_data(device, &uverbs_client);
675 
676 	if (!uverbs_dev)
677 		return;
678 
679 	class_device_unregister(&uverbs_dev->class_dev);
680 }
681 
682 static struct super_block *uverbs_event_get_sb(struct file_system_type *fs_type, int flags,
683 					       const char *dev_name, void *data)
684 {
685 	return get_sb_pseudo(fs_type, "infinibandevent:", NULL,
686 			     INFINIBANDEVENTFS_MAGIC);
687 }
688 
689 static struct file_system_type uverbs_event_fs = {
690 	/* No owner field so module can be unloaded */
691 	.name    = "infinibandeventfs",
692 	.get_sb  = uverbs_event_get_sb,
693 	.kill_sb = kill_litter_super
694 };
695 
696 static int __init ib_uverbs_init(void)
697 {
698 	int ret;
699 
700 	spin_lock_init(&map_lock);
701 
702 	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
703 				     "infiniband_verbs");
704 	if (ret) {
705 		printk(KERN_ERR "user_verbs: couldn't register device number\n");
706 		goto out;
707 	}
708 
709 	ret = class_register(&uverbs_class);
710 	if (ret) {
711 		printk(KERN_ERR "user_verbs: couldn't create class infiniband_verbs\n");
712 		goto out_chrdev;
713 	}
714 
715 	ret = class_create_file(&uverbs_class, &class_attr_abi_version);
716 	if (ret) {
717 		printk(KERN_ERR "user_verbs: couldn't create abi_version attribute\n");
718 		goto out_class;
719 	}
720 
721 	ret = register_filesystem(&uverbs_event_fs);
722 	if (ret) {
723 		printk(KERN_ERR "user_verbs: couldn't register infinibandeventfs\n");
724 		goto out_class;
725 	}
726 
727 	uverbs_event_mnt = kern_mount(&uverbs_event_fs);
728 	if (IS_ERR(uverbs_event_mnt)) {
729 		ret = PTR_ERR(uverbs_event_mnt);
730 		printk(KERN_ERR "user_verbs: couldn't mount infinibandeventfs\n");
731 		goto out_fs;
732 	}
733 
734 	ret = ib_register_client(&uverbs_client);
735 	if (ret) {
736 		printk(KERN_ERR "user_verbs: couldn't register client\n");
737 		goto out_mnt;
738 	}
739 
740 	return 0;
741 
742 out_mnt:
743 	mntput(uverbs_event_mnt);
744 
745 out_fs:
746 	unregister_filesystem(&uverbs_event_fs);
747 
748 out_class:
749 	class_unregister(&uverbs_class);
750 
751 out_chrdev:
752 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
753 
754 out:
755 	return ret;
756 }
757 
758 static void __exit ib_uverbs_cleanup(void)
759 {
760 	ib_unregister_client(&uverbs_client);
761 	mntput(uverbs_event_mnt);
762 	unregister_filesystem(&uverbs_event_fs);
763 	class_unregister(&uverbs_class);
764 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
765 }
766 
767 module_init(ib_uverbs_init);
768 module_exit(ib_uverbs_cleanup);
769