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