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/mount.h>
46 #include <linux/cdev.h>
47 
48 #include <asm/uaccess.h>
49 
50 #include "uverbs.h"
51 
52 MODULE_AUTHOR("Roland Dreier");
53 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
54 MODULE_LICENSE("Dual BSD/GPL");
55 
56 #define INFINIBANDEVENTFS_MAGIC	0x49426576	/* "IBev" */
57 
58 enum {
59 	IB_UVERBS_MAJOR       = 231,
60 	IB_UVERBS_BASE_MINOR  = 192,
61 	IB_UVERBS_MAX_DEVICES = 32
62 };
63 
64 #define IB_UVERBS_BASE_DEV	MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
65 
66 static struct class *uverbs_class;
67 
68 DEFINE_SPINLOCK(ib_uverbs_idr_lock);
69 DEFINE_IDR(ib_uverbs_pd_idr);
70 DEFINE_IDR(ib_uverbs_mr_idr);
71 DEFINE_IDR(ib_uverbs_mw_idr);
72 DEFINE_IDR(ib_uverbs_ah_idr);
73 DEFINE_IDR(ib_uverbs_cq_idr);
74 DEFINE_IDR(ib_uverbs_qp_idr);
75 DEFINE_IDR(ib_uverbs_srq_idr);
76 
77 static DEFINE_SPINLOCK(map_lock);
78 static struct ib_uverbs_device *dev_table[IB_UVERBS_MAX_DEVICES];
79 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
80 
81 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
82 				     const char __user *buf, int in_len,
83 				     int out_len) = {
84 	[IB_USER_VERBS_CMD_GET_CONTEXT]   	= ib_uverbs_get_context,
85 	[IB_USER_VERBS_CMD_QUERY_DEVICE]  	= ib_uverbs_query_device,
86 	[IB_USER_VERBS_CMD_QUERY_PORT]    	= ib_uverbs_query_port,
87 	[IB_USER_VERBS_CMD_ALLOC_PD]      	= ib_uverbs_alloc_pd,
88 	[IB_USER_VERBS_CMD_DEALLOC_PD]    	= ib_uverbs_dealloc_pd,
89 	[IB_USER_VERBS_CMD_REG_MR]        	= ib_uverbs_reg_mr,
90 	[IB_USER_VERBS_CMD_DEREG_MR]      	= ib_uverbs_dereg_mr,
91 	[IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
92 	[IB_USER_VERBS_CMD_CREATE_CQ]     	= ib_uverbs_create_cq,
93 	[IB_USER_VERBS_CMD_RESIZE_CQ]     	= ib_uverbs_resize_cq,
94 	[IB_USER_VERBS_CMD_POLL_CQ]     	= ib_uverbs_poll_cq,
95 	[IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]     	= ib_uverbs_req_notify_cq,
96 	[IB_USER_VERBS_CMD_DESTROY_CQ]    	= ib_uverbs_destroy_cq,
97 	[IB_USER_VERBS_CMD_CREATE_QP]     	= ib_uverbs_create_qp,
98 	[IB_USER_VERBS_CMD_QUERY_QP]     	= ib_uverbs_query_qp,
99 	[IB_USER_VERBS_CMD_MODIFY_QP]     	= ib_uverbs_modify_qp,
100 	[IB_USER_VERBS_CMD_DESTROY_QP]    	= ib_uverbs_destroy_qp,
101 	[IB_USER_VERBS_CMD_POST_SEND]    	= ib_uverbs_post_send,
102 	[IB_USER_VERBS_CMD_POST_RECV]    	= ib_uverbs_post_recv,
103 	[IB_USER_VERBS_CMD_POST_SRQ_RECV]    	= ib_uverbs_post_srq_recv,
104 	[IB_USER_VERBS_CMD_CREATE_AH]    	= ib_uverbs_create_ah,
105 	[IB_USER_VERBS_CMD_DESTROY_AH]    	= ib_uverbs_destroy_ah,
106 	[IB_USER_VERBS_CMD_ATTACH_MCAST]  	= ib_uverbs_attach_mcast,
107 	[IB_USER_VERBS_CMD_DETACH_MCAST]  	= ib_uverbs_detach_mcast,
108 	[IB_USER_VERBS_CMD_CREATE_SRQ]    	= ib_uverbs_create_srq,
109 	[IB_USER_VERBS_CMD_MODIFY_SRQ]    	= ib_uverbs_modify_srq,
110 	[IB_USER_VERBS_CMD_QUERY_SRQ]     	= ib_uverbs_query_srq,
111 	[IB_USER_VERBS_CMD_DESTROY_SRQ]   	= ib_uverbs_destroy_srq,
112 };
113 
114 static struct vfsmount *uverbs_event_mnt;
115 
116 static void ib_uverbs_add_one(struct ib_device *device);
117 static void ib_uverbs_remove_one(struct ib_device *device);
118 
119 static void ib_uverbs_release_dev(struct kref *ref)
120 {
121 	struct ib_uverbs_device *dev =
122 		container_of(ref, struct ib_uverbs_device, ref);
123 
124 	complete(&dev->comp);
125 }
126 
127 static void ib_uverbs_release_event_file(struct kref *ref)
128 {
129 	struct ib_uverbs_event_file *file =
130 		container_of(ref, struct ib_uverbs_event_file, ref);
131 
132 	kfree(file);
133 }
134 
135 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
136 			  struct ib_uverbs_event_file *ev_file,
137 			  struct ib_ucq_object *uobj)
138 {
139 	struct ib_uverbs_event *evt, *tmp;
140 
141 	if (ev_file) {
142 		spin_lock_irq(&ev_file->lock);
143 		list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
144 			list_del(&evt->list);
145 			kfree(evt);
146 		}
147 		spin_unlock_irq(&ev_file->lock);
148 
149 		kref_put(&ev_file->ref, ib_uverbs_release_event_file);
150 	}
151 
152 	spin_lock_irq(&file->async_file->lock);
153 	list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
154 		list_del(&evt->list);
155 		kfree(evt);
156 	}
157 	spin_unlock_irq(&file->async_file->lock);
158 }
159 
160 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
161 			      struct ib_uevent_object *uobj)
162 {
163 	struct ib_uverbs_event *evt, *tmp;
164 
165 	spin_lock_irq(&file->async_file->lock);
166 	list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
167 		list_del(&evt->list);
168 		kfree(evt);
169 	}
170 	spin_unlock_irq(&file->async_file->lock);
171 }
172 
173 static void ib_uverbs_detach_umcast(struct ib_qp *qp,
174 				    struct ib_uqp_object *uobj)
175 {
176 	struct ib_uverbs_mcast_entry *mcast, *tmp;
177 
178 	list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
179 		ib_detach_mcast(qp, &mcast->gid, mcast->lid);
180 		list_del(&mcast->list);
181 		kfree(mcast);
182 	}
183 }
184 
185 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
186 				      struct ib_ucontext *context)
187 {
188 	struct ib_uobject *uobj, *tmp;
189 
190 	if (!context)
191 		return 0;
192 
193 	context->closing = 1;
194 
195 	list_for_each_entry_safe(uobj, tmp, &context->ah_list, list) {
196 		struct ib_ah *ah = uobj->object;
197 
198 		idr_remove_uobj(&ib_uverbs_ah_idr, uobj);
199 		ib_destroy_ah(ah);
200 		kfree(uobj);
201 	}
202 
203 	list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {
204 		struct ib_qp *qp = uobj->object;
205 		struct ib_uqp_object *uqp =
206 			container_of(uobj, struct ib_uqp_object, uevent.uobject);
207 
208 		idr_remove_uobj(&ib_uverbs_qp_idr, uobj);
209 		ib_uverbs_detach_umcast(qp, uqp);
210 		ib_destroy_qp(qp);
211 		ib_uverbs_release_uevent(file, &uqp->uevent);
212 		kfree(uqp);
213 	}
214 
215 	list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {
216 		struct ib_cq *cq = uobj->object;
217 		struct ib_uverbs_event_file *ev_file = cq->cq_context;
218 		struct ib_ucq_object *ucq =
219 			container_of(uobj, struct ib_ucq_object, uobject);
220 
221 		idr_remove_uobj(&ib_uverbs_cq_idr, uobj);
222 		ib_destroy_cq(cq);
223 		ib_uverbs_release_ucq(file, ev_file, ucq);
224 		kfree(ucq);
225 	}
226 
227 	list_for_each_entry_safe(uobj, tmp, &context->srq_list, list) {
228 		struct ib_srq *srq = uobj->object;
229 		struct ib_uevent_object *uevent =
230 			container_of(uobj, struct ib_uevent_object, uobject);
231 
232 		idr_remove_uobj(&ib_uverbs_srq_idr, uobj);
233 		ib_destroy_srq(srq);
234 		ib_uverbs_release_uevent(file, uevent);
235 		kfree(uevent);
236 	}
237 
238 	/* XXX Free MWs */
239 
240 	list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {
241 		struct ib_mr *mr = uobj->object;
242 
243 		idr_remove_uobj(&ib_uverbs_mr_idr, uobj);
244 		ib_dereg_mr(mr);
245 		kfree(uobj);
246 	}
247 
248 	list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
249 		struct ib_pd *pd = uobj->object;
250 
251 		idr_remove_uobj(&ib_uverbs_pd_idr, uobj);
252 		ib_dealloc_pd(pd);
253 		kfree(uobj);
254 	}
255 
256 	return context->device->dealloc_ucontext(context);
257 }
258 
259 static void ib_uverbs_release_file(struct kref *ref)
260 {
261 	struct ib_uverbs_file *file =
262 		container_of(ref, struct ib_uverbs_file, ref);
263 
264 	module_put(file->device->ib_dev->owner);
265 	kref_put(&file->device->ref, ib_uverbs_release_dev);
266 
267 	kfree(file);
268 }
269 
270 static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,
271 				    size_t count, loff_t *pos)
272 {
273 	struct ib_uverbs_event_file *file = filp->private_data;
274 	struct ib_uverbs_event *event;
275 	int eventsz;
276 	int ret = 0;
277 
278 	spin_lock_irq(&file->lock);
279 
280 	while (list_empty(&file->event_list)) {
281 		spin_unlock_irq(&file->lock);
282 
283 		if (filp->f_flags & O_NONBLOCK)
284 			return -EAGAIN;
285 
286 		if (wait_event_interruptible(file->poll_wait,
287 					     !list_empty(&file->event_list)))
288 			return -ERESTARTSYS;
289 
290 		spin_lock_irq(&file->lock);
291 	}
292 
293 	event = list_entry(file->event_list.next, struct ib_uverbs_event, list);
294 
295 	if (file->is_async)
296 		eventsz = sizeof (struct ib_uverbs_async_event_desc);
297 	else
298 		eventsz = sizeof (struct ib_uverbs_comp_event_desc);
299 
300 	if (eventsz > count) {
301 		ret   = -EINVAL;
302 		event = NULL;
303 	} else {
304 		list_del(file->event_list.next);
305 		if (event->counter) {
306 			++(*event->counter);
307 			list_del(&event->obj_list);
308 		}
309 	}
310 
311 	spin_unlock_irq(&file->lock);
312 
313 	if (event) {
314 		if (copy_to_user(buf, event, eventsz))
315 			ret = -EFAULT;
316 		else
317 			ret = eventsz;
318 	}
319 
320 	kfree(event);
321 
322 	return ret;
323 }
324 
325 static unsigned int ib_uverbs_event_poll(struct file *filp,
326 					 struct poll_table_struct *wait)
327 {
328 	unsigned int pollflags = 0;
329 	struct ib_uverbs_event_file *file = filp->private_data;
330 
331 	poll_wait(filp, &file->poll_wait, wait);
332 
333 	spin_lock_irq(&file->lock);
334 	if (!list_empty(&file->event_list))
335 		pollflags = POLLIN | POLLRDNORM;
336 	spin_unlock_irq(&file->lock);
337 
338 	return pollflags;
339 }
340 
341 static int ib_uverbs_event_fasync(int fd, struct file *filp, int on)
342 {
343 	struct ib_uverbs_event_file *file = filp->private_data;
344 
345 	return fasync_helper(fd, filp, on, &file->async_queue);
346 }
347 
348 static int ib_uverbs_event_close(struct inode *inode, struct file *filp)
349 {
350 	struct ib_uverbs_event_file *file = filp->private_data;
351 	struct ib_uverbs_event *entry, *tmp;
352 
353 	spin_lock_irq(&file->lock);
354 	file->is_closed = 1;
355 	list_for_each_entry_safe(entry, tmp, &file->event_list, list) {
356 		if (entry->counter)
357 			list_del(&entry->obj_list);
358 		kfree(entry);
359 	}
360 	spin_unlock_irq(&file->lock);
361 
362 	if (file->is_async) {
363 		ib_unregister_event_handler(&file->uverbs_file->event_handler);
364 		kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);
365 	}
366 	kref_put(&file->ref, ib_uverbs_release_event_file);
367 
368 	return 0;
369 }
370 
371 static const struct file_operations uverbs_event_fops = {
372 	.owner	 = THIS_MODULE,
373 	.read 	 = ib_uverbs_event_read,
374 	.poll    = ib_uverbs_event_poll,
375 	.release = ib_uverbs_event_close,
376 	.fasync  = ib_uverbs_event_fasync
377 };
378 
379 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
380 {
381 	struct ib_uverbs_event_file    *file = cq_context;
382 	struct ib_ucq_object	       *uobj;
383 	struct ib_uverbs_event	       *entry;
384 	unsigned long			flags;
385 
386 	if (!file)
387 		return;
388 
389 	spin_lock_irqsave(&file->lock, flags);
390 	if (file->is_closed) {
391 		spin_unlock_irqrestore(&file->lock, flags);
392 		return;
393 	}
394 
395 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
396 	if (!entry) {
397 		spin_unlock_irqrestore(&file->lock, flags);
398 		return;
399 	}
400 
401 	uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
402 
403 	entry->desc.comp.cq_handle = cq->uobject->user_handle;
404 	entry->counter		   = &uobj->comp_events_reported;
405 
406 	list_add_tail(&entry->list, &file->event_list);
407 	list_add_tail(&entry->obj_list, &uobj->comp_list);
408 	spin_unlock_irqrestore(&file->lock, flags);
409 
410 	wake_up_interruptible(&file->poll_wait);
411 	kill_fasync(&file->async_queue, SIGIO, POLL_IN);
412 }
413 
414 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
415 				    __u64 element, __u64 event,
416 				    struct list_head *obj_list,
417 				    u32 *counter)
418 {
419 	struct ib_uverbs_event *entry;
420 	unsigned long flags;
421 
422 	spin_lock_irqsave(&file->async_file->lock, flags);
423 	if (file->async_file->is_closed) {
424 		spin_unlock_irqrestore(&file->async_file->lock, flags);
425 		return;
426 	}
427 
428 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
429 	if (!entry) {
430 		spin_unlock_irqrestore(&file->async_file->lock, flags);
431 		return;
432 	}
433 
434 	entry->desc.async.element    = element;
435 	entry->desc.async.event_type = event;
436 	entry->counter               = counter;
437 
438 	list_add_tail(&entry->list, &file->async_file->event_list);
439 	if (obj_list)
440 		list_add_tail(&entry->obj_list, obj_list);
441 	spin_unlock_irqrestore(&file->async_file->lock, flags);
442 
443 	wake_up_interruptible(&file->async_file->poll_wait);
444 	kill_fasync(&file->async_file->async_queue, SIGIO, POLL_IN);
445 }
446 
447 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
448 {
449 	struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
450 						  struct ib_ucq_object, uobject);
451 
452 	ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
453 				event->event, &uobj->async_list,
454 				&uobj->async_events_reported);
455 }
456 
457 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
458 {
459 	struct ib_uevent_object *uobj;
460 
461 	uobj = container_of(event->element.qp->uobject,
462 			    struct ib_uevent_object, uobject);
463 
464 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
465 				event->event, &uobj->event_list,
466 				&uobj->events_reported);
467 }
468 
469 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
470 {
471 	struct ib_uevent_object *uobj;
472 
473 	uobj = container_of(event->element.srq->uobject,
474 			    struct ib_uevent_object, uobject);
475 
476 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
477 				event->event, &uobj->event_list,
478 				&uobj->events_reported);
479 }
480 
481 void ib_uverbs_event_handler(struct ib_event_handler *handler,
482 			     struct ib_event *event)
483 {
484 	struct ib_uverbs_file *file =
485 		container_of(handler, struct ib_uverbs_file, event_handler);
486 
487 	ib_uverbs_async_handler(file, event->element.port_num, event->event,
488 				NULL, NULL);
489 }
490 
491 struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
492 					int is_async, int *fd)
493 {
494 	struct ib_uverbs_event_file *ev_file;
495 	struct path path;
496 	struct file *filp;
497 	int ret;
498 
499 	ev_file = kmalloc(sizeof *ev_file, GFP_KERNEL);
500 	if (!ev_file)
501 		return ERR_PTR(-ENOMEM);
502 
503 	kref_init(&ev_file->ref);
504 	spin_lock_init(&ev_file->lock);
505 	INIT_LIST_HEAD(&ev_file->event_list);
506 	init_waitqueue_head(&ev_file->poll_wait);
507 	ev_file->uverbs_file = uverbs_file;
508 	ev_file->async_queue = NULL;
509 	ev_file->is_async    = is_async;
510 	ev_file->is_closed   = 0;
511 
512 	*fd = get_unused_fd();
513 	if (*fd < 0) {
514 		ret = *fd;
515 		goto err;
516 	}
517 
518 	/*
519 	 * fops_get() can't fail here, because we're coming from a
520 	 * system call on a uverbs file, which will already have a
521 	 * module reference.
522 	 */
523 	path.mnt = uverbs_event_mnt;
524 	path.dentry = uverbs_event_mnt->mnt_root;
525 	path_get(&path);
526 	filp = alloc_file(&path, FMODE_READ, fops_get(&uverbs_event_fops));
527 	if (!filp) {
528 		ret = -ENFILE;
529 		goto err_fd;
530 	}
531 
532 	filp->private_data = ev_file;
533 
534 	return filp;
535 
536 err_fd:
537 	fops_put(&uverbs_event_fops);
538 	path_put(&path);
539 	put_unused_fd(*fd);
540 
541 err:
542 	kfree(ev_file);
543 	return ERR_PTR(ret);
544 }
545 
546 /*
547  * Look up a completion event file by FD.  If lookup is successful,
548  * takes a ref to the event file struct that it returns; if
549  * unsuccessful, returns NULL.
550  */
551 struct ib_uverbs_event_file *ib_uverbs_lookup_comp_file(int fd)
552 {
553 	struct ib_uverbs_event_file *ev_file = NULL;
554 	struct file *filp;
555 
556 	filp = fget(fd);
557 	if (!filp)
558 		return NULL;
559 
560 	if (filp->f_op != &uverbs_event_fops)
561 		goto out;
562 
563 	ev_file = filp->private_data;
564 	if (ev_file->is_async) {
565 		ev_file = NULL;
566 		goto out;
567 	}
568 
569 	kref_get(&ev_file->ref);
570 
571 out:
572 	fput(filp);
573 	return ev_file;
574 }
575 
576 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
577 			     size_t count, loff_t *pos)
578 {
579 	struct ib_uverbs_file *file = filp->private_data;
580 	struct ib_uverbs_cmd_hdr hdr;
581 
582 	if (count < sizeof hdr)
583 		return -EINVAL;
584 
585 	if (copy_from_user(&hdr, buf, sizeof hdr))
586 		return -EFAULT;
587 
588 	if (hdr.in_words * 4 != count)
589 		return -EINVAL;
590 
591 	if (hdr.command < 0				||
592 	    hdr.command >= ARRAY_SIZE(uverbs_cmd_table) ||
593 	    !uverbs_cmd_table[hdr.command])
594 		return -EINVAL;
595 
596 	if (!file->ucontext &&
597 	    hdr.command != IB_USER_VERBS_CMD_GET_CONTEXT)
598 		return -EINVAL;
599 
600 	if (!(file->device->ib_dev->uverbs_cmd_mask & (1ull << hdr.command)))
601 		return -ENOSYS;
602 
603 	return uverbs_cmd_table[hdr.command](file, buf + sizeof hdr,
604 					     hdr.in_words * 4, hdr.out_words * 4);
605 }
606 
607 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
608 {
609 	struct ib_uverbs_file *file = filp->private_data;
610 
611 	if (!file->ucontext)
612 		return -ENODEV;
613 	else
614 		return file->device->ib_dev->mmap(file->ucontext, vma);
615 }
616 
617 /*
618  * ib_uverbs_open() does not need the BKL:
619  *
620  *  - dev_table[] accesses are protected by map_lock, the
621  *    ib_uverbs_device structures are properly reference counted, and
622  *    everything else is purely local to the file being created, so
623  *    races against other open calls are not a problem;
624  *  - there is no ioctl method to race against;
625  *  - the device is added to dev_table[] as the last part of module
626  *    initialization, the open method will either immediately run
627  *    -ENXIO, or all required initialization will be done.
628  */
629 static int ib_uverbs_open(struct inode *inode, struct file *filp)
630 {
631 	struct ib_uverbs_device *dev;
632 	struct ib_uverbs_file *file;
633 	int ret;
634 
635 	spin_lock(&map_lock);
636 	dev = dev_table[iminor(inode) - IB_UVERBS_BASE_MINOR];
637 	if (dev)
638 		kref_get(&dev->ref);
639 	spin_unlock(&map_lock);
640 
641 	if (!dev)
642 		return -ENXIO;
643 
644 	if (!try_module_get(dev->ib_dev->owner)) {
645 		ret = -ENODEV;
646 		goto err;
647 	}
648 
649 	file = kmalloc(sizeof *file, GFP_KERNEL);
650 	if (!file) {
651 		ret = -ENOMEM;
652 		goto err_module;
653 	}
654 
655 	file->device	 = dev;
656 	file->ucontext	 = NULL;
657 	file->async_file = NULL;
658 	kref_init(&file->ref);
659 	mutex_init(&file->mutex);
660 
661 	filp->private_data = file;
662 
663 	return 0;
664 
665 err_module:
666 	module_put(dev->ib_dev->owner);
667 
668 err:
669 	kref_put(&dev->ref, ib_uverbs_release_dev);
670 	return ret;
671 }
672 
673 static int ib_uverbs_close(struct inode *inode, struct file *filp)
674 {
675 	struct ib_uverbs_file *file = filp->private_data;
676 
677 	ib_uverbs_cleanup_ucontext(file, file->ucontext);
678 
679 	if (file->async_file)
680 		kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
681 
682 	kref_put(&file->ref, ib_uverbs_release_file);
683 
684 	return 0;
685 }
686 
687 static const struct file_operations uverbs_fops = {
688 	.owner 	 = THIS_MODULE,
689 	.write 	 = ib_uverbs_write,
690 	.open 	 = ib_uverbs_open,
691 	.release = ib_uverbs_close
692 };
693 
694 static const struct file_operations uverbs_mmap_fops = {
695 	.owner 	 = THIS_MODULE,
696 	.write 	 = ib_uverbs_write,
697 	.mmap    = ib_uverbs_mmap,
698 	.open 	 = ib_uverbs_open,
699 	.release = ib_uverbs_close
700 };
701 
702 static struct ib_client uverbs_client = {
703 	.name   = "uverbs",
704 	.add    = ib_uverbs_add_one,
705 	.remove = ib_uverbs_remove_one
706 };
707 
708 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
709 			  char *buf)
710 {
711 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
712 
713 	if (!dev)
714 		return -ENODEV;
715 
716 	return sprintf(buf, "%s\n", dev->ib_dev->name);
717 }
718 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
719 
720 static ssize_t show_dev_abi_version(struct device *device,
721 				    struct device_attribute *attr, char *buf)
722 {
723 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
724 
725 	if (!dev)
726 		return -ENODEV;
727 
728 	return sprintf(buf, "%d\n", dev->ib_dev->uverbs_abi_ver);
729 }
730 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
731 
732 static ssize_t show_abi_version(struct class *class, char *buf)
733 {
734 	return sprintf(buf, "%d\n", IB_USER_VERBS_ABI_VERSION);
735 }
736 static CLASS_ATTR(abi_version, S_IRUGO, show_abi_version, NULL);
737 
738 static void ib_uverbs_add_one(struct ib_device *device)
739 {
740 	struct ib_uverbs_device *uverbs_dev;
741 
742 	if (!device->alloc_ucontext)
743 		return;
744 
745 	uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
746 	if (!uverbs_dev)
747 		return;
748 
749 	kref_init(&uverbs_dev->ref);
750 	init_completion(&uverbs_dev->comp);
751 
752 	spin_lock(&map_lock);
753 	uverbs_dev->devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
754 	if (uverbs_dev->devnum >= IB_UVERBS_MAX_DEVICES) {
755 		spin_unlock(&map_lock);
756 		goto err;
757 	}
758 	set_bit(uverbs_dev->devnum, dev_map);
759 	spin_unlock(&map_lock);
760 
761 	uverbs_dev->ib_dev           = device;
762 	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
763 
764 	uverbs_dev->cdev = cdev_alloc();
765 	if (!uverbs_dev->cdev)
766 		goto err;
767 	uverbs_dev->cdev->owner = THIS_MODULE;
768 	uverbs_dev->cdev->ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
769 	kobject_set_name(&uverbs_dev->cdev->kobj, "uverbs%d", uverbs_dev->devnum);
770 	if (cdev_add(uverbs_dev->cdev, IB_UVERBS_BASE_DEV + uverbs_dev->devnum, 1))
771 		goto err_cdev;
772 
773 	uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
774 					uverbs_dev->cdev->dev, uverbs_dev,
775 					"uverbs%d", uverbs_dev->devnum);
776 	if (IS_ERR(uverbs_dev->dev))
777 		goto err_cdev;
778 
779 	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
780 		goto err_class;
781 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
782 		goto err_class;
783 
784 	spin_lock(&map_lock);
785 	dev_table[uverbs_dev->devnum] = uverbs_dev;
786 	spin_unlock(&map_lock);
787 
788 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
789 
790 	return;
791 
792 err_class:
793 	device_destroy(uverbs_class, uverbs_dev->cdev->dev);
794 
795 err_cdev:
796 	cdev_del(uverbs_dev->cdev);
797 	clear_bit(uverbs_dev->devnum, dev_map);
798 
799 err:
800 	kref_put(&uverbs_dev->ref, ib_uverbs_release_dev);
801 	wait_for_completion(&uverbs_dev->comp);
802 	kfree(uverbs_dev);
803 	return;
804 }
805 
806 static void ib_uverbs_remove_one(struct ib_device *device)
807 {
808 	struct ib_uverbs_device *uverbs_dev = ib_get_client_data(device, &uverbs_client);
809 
810 	if (!uverbs_dev)
811 		return;
812 
813 	dev_set_drvdata(uverbs_dev->dev, NULL);
814 	device_destroy(uverbs_class, uverbs_dev->cdev->dev);
815 	cdev_del(uverbs_dev->cdev);
816 
817 	spin_lock(&map_lock);
818 	dev_table[uverbs_dev->devnum] = NULL;
819 	spin_unlock(&map_lock);
820 
821 	clear_bit(uverbs_dev->devnum, dev_map);
822 
823 	kref_put(&uverbs_dev->ref, ib_uverbs_release_dev);
824 	wait_for_completion(&uverbs_dev->comp);
825 	kfree(uverbs_dev);
826 }
827 
828 static int uverbs_event_get_sb(struct file_system_type *fs_type, int flags,
829 			       const char *dev_name, void *data,
830 			       struct vfsmount *mnt)
831 {
832 	return get_sb_pseudo(fs_type, "infinibandevent:", NULL,
833 			     INFINIBANDEVENTFS_MAGIC, mnt);
834 }
835 
836 static struct file_system_type uverbs_event_fs = {
837 	/* No owner field so module can be unloaded */
838 	.name    = "infinibandeventfs",
839 	.get_sb  = uverbs_event_get_sb,
840 	.kill_sb = kill_litter_super
841 };
842 
843 static int __init ib_uverbs_init(void)
844 {
845 	int ret;
846 
847 	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
848 				     "infiniband_verbs");
849 	if (ret) {
850 		printk(KERN_ERR "user_verbs: couldn't register device number\n");
851 		goto out;
852 	}
853 
854 	uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
855 	if (IS_ERR(uverbs_class)) {
856 		ret = PTR_ERR(uverbs_class);
857 		printk(KERN_ERR "user_verbs: couldn't create class infiniband_verbs\n");
858 		goto out_chrdev;
859 	}
860 
861 	ret = class_create_file(uverbs_class, &class_attr_abi_version);
862 	if (ret) {
863 		printk(KERN_ERR "user_verbs: couldn't create abi_version attribute\n");
864 		goto out_class;
865 	}
866 
867 	ret = register_filesystem(&uverbs_event_fs);
868 	if (ret) {
869 		printk(KERN_ERR "user_verbs: couldn't register infinibandeventfs\n");
870 		goto out_class;
871 	}
872 
873 	uverbs_event_mnt = kern_mount(&uverbs_event_fs);
874 	if (IS_ERR(uverbs_event_mnt)) {
875 		ret = PTR_ERR(uverbs_event_mnt);
876 		printk(KERN_ERR "user_verbs: couldn't mount infinibandeventfs\n");
877 		goto out_fs;
878 	}
879 
880 	ret = ib_register_client(&uverbs_client);
881 	if (ret) {
882 		printk(KERN_ERR "user_verbs: couldn't register client\n");
883 		goto out_mnt;
884 	}
885 
886 	return 0;
887 
888 out_mnt:
889 	mntput(uverbs_event_mnt);
890 
891 out_fs:
892 	unregister_filesystem(&uverbs_event_fs);
893 
894 out_class:
895 	class_destroy(uverbs_class);
896 
897 out_chrdev:
898 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
899 
900 out:
901 	return ret;
902 }
903 
904 static void __exit ib_uverbs_cleanup(void)
905 {
906 	ib_unregister_client(&uverbs_client);
907 	mntput(uverbs_event_mnt);
908 	unregister_filesystem(&uverbs_event_fs);
909 	class_destroy(uverbs_class);
910 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
911 	idr_destroy(&ib_uverbs_pd_idr);
912 	idr_destroy(&ib_uverbs_mr_idr);
913 	idr_destroy(&ib_uverbs_mw_idr);
914 	idr_destroy(&ib_uverbs_ah_idr);
915 	idr_destroy(&ib_uverbs_cq_idr);
916 	idr_destroy(&ib_uverbs_qp_idr);
917 	idr_destroy(&ib_uverbs_srq_idr);
918 }
919 
920 module_init(ib_uverbs_init);
921 module_exit(ib_uverbs_cleanup);
922