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 				     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_REREG_MR]		= ib_uverbs_rereg_mr,
91 	[IB_USER_VERBS_CMD_DEREG_MR]		= ib_uverbs_dereg_mr,
92 	[IB_USER_VERBS_CMD_ALLOC_MW]		= ib_uverbs_alloc_mw,
93 	[IB_USER_VERBS_CMD_DEALLOC_MW]		= ib_uverbs_dealloc_mw,
94 	[IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
95 	[IB_USER_VERBS_CMD_CREATE_CQ]		= ib_uverbs_create_cq,
96 	[IB_USER_VERBS_CMD_RESIZE_CQ]		= ib_uverbs_resize_cq,
97 	[IB_USER_VERBS_CMD_POLL_CQ]		= ib_uverbs_poll_cq,
98 	[IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]	= ib_uverbs_req_notify_cq,
99 	[IB_USER_VERBS_CMD_DESTROY_CQ]		= ib_uverbs_destroy_cq,
100 	[IB_USER_VERBS_CMD_CREATE_QP]		= ib_uverbs_create_qp,
101 	[IB_USER_VERBS_CMD_QUERY_QP]		= ib_uverbs_query_qp,
102 	[IB_USER_VERBS_CMD_MODIFY_QP]		= ib_uverbs_modify_qp,
103 	[IB_USER_VERBS_CMD_DESTROY_QP]		= ib_uverbs_destroy_qp,
104 	[IB_USER_VERBS_CMD_POST_SEND]		= ib_uverbs_post_send,
105 	[IB_USER_VERBS_CMD_POST_RECV]		= ib_uverbs_post_recv,
106 	[IB_USER_VERBS_CMD_POST_SRQ_RECV]	= ib_uverbs_post_srq_recv,
107 	[IB_USER_VERBS_CMD_CREATE_AH]		= ib_uverbs_create_ah,
108 	[IB_USER_VERBS_CMD_DESTROY_AH]		= ib_uverbs_destroy_ah,
109 	[IB_USER_VERBS_CMD_ATTACH_MCAST]	= ib_uverbs_attach_mcast,
110 	[IB_USER_VERBS_CMD_DETACH_MCAST]	= ib_uverbs_detach_mcast,
111 	[IB_USER_VERBS_CMD_CREATE_SRQ]		= ib_uverbs_create_srq,
112 	[IB_USER_VERBS_CMD_MODIFY_SRQ]		= ib_uverbs_modify_srq,
113 	[IB_USER_VERBS_CMD_QUERY_SRQ]		= ib_uverbs_query_srq,
114 	[IB_USER_VERBS_CMD_DESTROY_SRQ]		= ib_uverbs_destroy_srq,
115 	[IB_USER_VERBS_CMD_OPEN_XRCD]		= ib_uverbs_open_xrcd,
116 	[IB_USER_VERBS_CMD_CLOSE_XRCD]		= ib_uverbs_close_xrcd,
117 	[IB_USER_VERBS_CMD_CREATE_XSRQ]		= ib_uverbs_create_xsrq,
118 	[IB_USER_VERBS_CMD_OPEN_QP]		= ib_uverbs_open_qp,
119 };
120 
121 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
122 				    struct ib_udata *ucore,
123 				    struct ib_udata *uhw) = {
124 	[IB_USER_VERBS_EX_CMD_CREATE_FLOW]	= ib_uverbs_ex_create_flow,
125 	[IB_USER_VERBS_EX_CMD_DESTROY_FLOW]	= ib_uverbs_ex_destroy_flow
126 };
127 
128 static void ib_uverbs_add_one(struct ib_device *device);
129 static void ib_uverbs_remove_one(struct ib_device *device);
130 
131 static void ib_uverbs_release_dev(struct kref *ref)
132 {
133 	struct ib_uverbs_device *dev =
134 		container_of(ref, struct ib_uverbs_device, ref);
135 
136 	complete(&dev->comp);
137 }
138 
139 static void ib_uverbs_release_event_file(struct kref *ref)
140 {
141 	struct ib_uverbs_event_file *file =
142 		container_of(ref, struct ib_uverbs_event_file, ref);
143 
144 	kfree(file);
145 }
146 
147 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
148 			  struct ib_uverbs_event_file *ev_file,
149 			  struct ib_ucq_object *uobj)
150 {
151 	struct ib_uverbs_event *evt, *tmp;
152 
153 	if (ev_file) {
154 		spin_lock_irq(&ev_file->lock);
155 		list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
156 			list_del(&evt->list);
157 			kfree(evt);
158 		}
159 		spin_unlock_irq(&ev_file->lock);
160 
161 		kref_put(&ev_file->ref, ib_uverbs_release_event_file);
162 	}
163 
164 	spin_lock_irq(&file->async_file->lock);
165 	list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
166 		list_del(&evt->list);
167 		kfree(evt);
168 	}
169 	spin_unlock_irq(&file->async_file->lock);
170 }
171 
172 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
173 			      struct ib_uevent_object *uobj)
174 {
175 	struct ib_uverbs_event *evt, *tmp;
176 
177 	spin_lock_irq(&file->async_file->lock);
178 	list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
179 		list_del(&evt->list);
180 		kfree(evt);
181 	}
182 	spin_unlock_irq(&file->async_file->lock);
183 }
184 
185 static void ib_uverbs_detach_umcast(struct ib_qp *qp,
186 				    struct ib_uqp_object *uobj)
187 {
188 	struct ib_uverbs_mcast_entry *mcast, *tmp;
189 
190 	list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
191 		ib_detach_mcast(qp, &mcast->gid, mcast->lid);
192 		list_del(&mcast->list);
193 		kfree(mcast);
194 	}
195 }
196 
197 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
198 				      struct ib_ucontext *context)
199 {
200 	struct ib_uobject *uobj, *tmp;
201 
202 	if (!context)
203 		return 0;
204 
205 	context->closing = 1;
206 
207 	list_for_each_entry_safe(uobj, tmp, &context->ah_list, list) {
208 		struct ib_ah *ah = uobj->object;
209 
210 		idr_remove_uobj(&ib_uverbs_ah_idr, uobj);
211 		ib_destroy_ah(ah);
212 		kfree(uobj);
213 	}
214 
215 	/* Remove MWs before QPs, in order to support type 2A MWs. */
216 	list_for_each_entry_safe(uobj, tmp, &context->mw_list, list) {
217 		struct ib_mw *mw = uobj->object;
218 
219 		idr_remove_uobj(&ib_uverbs_mw_idr, uobj);
220 		ib_dealloc_mw(mw);
221 		kfree(uobj);
222 	}
223 
224 	list_for_each_entry_safe(uobj, tmp, &context->rule_list, list) {
225 		struct ib_flow *flow_id = uobj->object;
226 
227 		idr_remove_uobj(&ib_uverbs_rule_idr, uobj);
228 		ib_destroy_flow(flow_id);
229 		kfree(uobj);
230 	}
231 
232 	list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {
233 		struct ib_qp *qp = uobj->object;
234 		struct ib_uqp_object *uqp =
235 			container_of(uobj, struct ib_uqp_object, uevent.uobject);
236 
237 		idr_remove_uobj(&ib_uverbs_qp_idr, uobj);
238 		if (qp != qp->real_qp) {
239 			ib_close_qp(qp);
240 		} else {
241 			ib_uverbs_detach_umcast(qp, uqp);
242 			ib_destroy_qp(qp);
243 		}
244 		ib_uverbs_release_uevent(file, &uqp->uevent);
245 		kfree(uqp);
246 	}
247 
248 	list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {
249 		struct ib_cq *cq = uobj->object;
250 		struct ib_uverbs_event_file *ev_file = cq->cq_context;
251 		struct ib_ucq_object *ucq =
252 			container_of(uobj, struct ib_ucq_object, uobject);
253 
254 		idr_remove_uobj(&ib_uverbs_cq_idr, uobj);
255 		ib_destroy_cq(cq);
256 		ib_uverbs_release_ucq(file, ev_file, ucq);
257 		kfree(ucq);
258 	}
259 
260 	list_for_each_entry_safe(uobj, tmp, &context->srq_list, list) {
261 		struct ib_srq *srq = uobj->object;
262 		struct ib_uevent_object *uevent =
263 			container_of(uobj, struct ib_uevent_object, uobject);
264 
265 		idr_remove_uobj(&ib_uverbs_srq_idr, uobj);
266 		ib_destroy_srq(srq);
267 		ib_uverbs_release_uevent(file, uevent);
268 		kfree(uevent);
269 	}
270 
271 	list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {
272 		struct ib_mr *mr = uobj->object;
273 
274 		idr_remove_uobj(&ib_uverbs_mr_idr, uobj);
275 		ib_dereg_mr(mr);
276 		kfree(uobj);
277 	}
278 
279 	mutex_lock(&file->device->xrcd_tree_mutex);
280 	list_for_each_entry_safe(uobj, tmp, &context->xrcd_list, list) {
281 		struct ib_xrcd *xrcd = uobj->object;
282 		struct ib_uxrcd_object *uxrcd =
283 			container_of(uobj, struct ib_uxrcd_object, uobject);
284 
285 		idr_remove_uobj(&ib_uverbs_xrcd_idr, uobj);
286 		ib_uverbs_dealloc_xrcd(file->device, xrcd);
287 		kfree(uxrcd);
288 	}
289 	mutex_unlock(&file->device->xrcd_tree_mutex);
290 
291 	list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
292 		struct ib_pd *pd = uobj->object;
293 
294 		idr_remove_uobj(&ib_uverbs_pd_idr, uobj);
295 		ib_dealloc_pd(pd);
296 		kfree(uobj);
297 	}
298 
299 	return context->device->dealloc_ucontext(context);
300 }
301 
302 static void ib_uverbs_release_file(struct kref *ref)
303 {
304 	struct ib_uverbs_file *file =
305 		container_of(ref, struct ib_uverbs_file, ref);
306 
307 	module_put(file->device->ib_dev->owner);
308 	kref_put(&file->device->ref, ib_uverbs_release_dev);
309 
310 	kfree(file);
311 }
312 
313 static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,
314 				    size_t count, loff_t *pos)
315 {
316 	struct ib_uverbs_event_file *file = filp->private_data;
317 	struct ib_uverbs_event *event;
318 	int eventsz;
319 	int ret = 0;
320 
321 	spin_lock_irq(&file->lock);
322 
323 	while (list_empty(&file->event_list)) {
324 		spin_unlock_irq(&file->lock);
325 
326 		if (filp->f_flags & O_NONBLOCK)
327 			return -EAGAIN;
328 
329 		if (wait_event_interruptible(file->poll_wait,
330 					     !list_empty(&file->event_list)))
331 			return -ERESTARTSYS;
332 
333 		spin_lock_irq(&file->lock);
334 	}
335 
336 	event = list_entry(file->event_list.next, struct ib_uverbs_event, list);
337 
338 	if (file->is_async)
339 		eventsz = sizeof (struct ib_uverbs_async_event_desc);
340 	else
341 		eventsz = sizeof (struct ib_uverbs_comp_event_desc);
342 
343 	if (eventsz > count) {
344 		ret   = -EINVAL;
345 		event = NULL;
346 	} else {
347 		list_del(file->event_list.next);
348 		if (event->counter) {
349 			++(*event->counter);
350 			list_del(&event->obj_list);
351 		}
352 	}
353 
354 	spin_unlock_irq(&file->lock);
355 
356 	if (event) {
357 		if (copy_to_user(buf, event, eventsz))
358 			ret = -EFAULT;
359 		else
360 			ret = eventsz;
361 	}
362 
363 	kfree(event);
364 
365 	return ret;
366 }
367 
368 static unsigned int ib_uverbs_event_poll(struct file *filp,
369 					 struct poll_table_struct *wait)
370 {
371 	unsigned int pollflags = 0;
372 	struct ib_uverbs_event_file *file = filp->private_data;
373 
374 	poll_wait(filp, &file->poll_wait, wait);
375 
376 	spin_lock_irq(&file->lock);
377 	if (!list_empty(&file->event_list))
378 		pollflags = POLLIN | POLLRDNORM;
379 	spin_unlock_irq(&file->lock);
380 
381 	return pollflags;
382 }
383 
384 static int ib_uverbs_event_fasync(int fd, struct file *filp, int on)
385 {
386 	struct ib_uverbs_event_file *file = filp->private_data;
387 
388 	return fasync_helper(fd, filp, on, &file->async_queue);
389 }
390 
391 static int ib_uverbs_event_close(struct inode *inode, struct file *filp)
392 {
393 	struct ib_uverbs_event_file *file = filp->private_data;
394 	struct ib_uverbs_event *entry, *tmp;
395 
396 	spin_lock_irq(&file->lock);
397 	file->is_closed = 1;
398 	list_for_each_entry_safe(entry, tmp, &file->event_list, list) {
399 		if (entry->counter)
400 			list_del(&entry->obj_list);
401 		kfree(entry);
402 	}
403 	spin_unlock_irq(&file->lock);
404 
405 	if (file->is_async) {
406 		ib_unregister_event_handler(&file->uverbs_file->event_handler);
407 		kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);
408 	}
409 	kref_put(&file->ref, ib_uverbs_release_event_file);
410 
411 	return 0;
412 }
413 
414 static const struct file_operations uverbs_event_fops = {
415 	.owner	 = THIS_MODULE,
416 	.read	 = ib_uverbs_event_read,
417 	.poll    = ib_uverbs_event_poll,
418 	.release = ib_uverbs_event_close,
419 	.fasync  = ib_uverbs_event_fasync,
420 	.llseek	 = no_llseek,
421 };
422 
423 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
424 {
425 	struct ib_uverbs_event_file    *file = cq_context;
426 	struct ib_ucq_object	       *uobj;
427 	struct ib_uverbs_event	       *entry;
428 	unsigned long			flags;
429 
430 	if (!file)
431 		return;
432 
433 	spin_lock_irqsave(&file->lock, flags);
434 	if (file->is_closed) {
435 		spin_unlock_irqrestore(&file->lock, flags);
436 		return;
437 	}
438 
439 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
440 	if (!entry) {
441 		spin_unlock_irqrestore(&file->lock, flags);
442 		return;
443 	}
444 
445 	uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
446 
447 	entry->desc.comp.cq_handle = cq->uobject->user_handle;
448 	entry->counter		   = &uobj->comp_events_reported;
449 
450 	list_add_tail(&entry->list, &file->event_list);
451 	list_add_tail(&entry->obj_list, &uobj->comp_list);
452 	spin_unlock_irqrestore(&file->lock, flags);
453 
454 	wake_up_interruptible(&file->poll_wait);
455 	kill_fasync(&file->async_queue, SIGIO, POLL_IN);
456 }
457 
458 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
459 				    __u64 element, __u64 event,
460 				    struct list_head *obj_list,
461 				    u32 *counter)
462 {
463 	struct ib_uverbs_event *entry;
464 	unsigned long flags;
465 
466 	spin_lock_irqsave(&file->async_file->lock, flags);
467 	if (file->async_file->is_closed) {
468 		spin_unlock_irqrestore(&file->async_file->lock, flags);
469 		return;
470 	}
471 
472 	entry = kmalloc(sizeof *entry, GFP_ATOMIC);
473 	if (!entry) {
474 		spin_unlock_irqrestore(&file->async_file->lock, flags);
475 		return;
476 	}
477 
478 	entry->desc.async.element    = element;
479 	entry->desc.async.event_type = event;
480 	entry->desc.async.reserved   = 0;
481 	entry->counter               = counter;
482 
483 	list_add_tail(&entry->list, &file->async_file->event_list);
484 	if (obj_list)
485 		list_add_tail(&entry->obj_list, obj_list);
486 	spin_unlock_irqrestore(&file->async_file->lock, flags);
487 
488 	wake_up_interruptible(&file->async_file->poll_wait);
489 	kill_fasync(&file->async_file->async_queue, SIGIO, POLL_IN);
490 }
491 
492 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
493 {
494 	struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
495 						  struct ib_ucq_object, uobject);
496 
497 	ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
498 				event->event, &uobj->async_list,
499 				&uobj->async_events_reported);
500 }
501 
502 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
503 {
504 	struct ib_uevent_object *uobj;
505 
506 	/* for XRC target qp's, check that qp is live */
507 	if (!event->element.qp->uobject || !event->element.qp->uobject->live)
508 		return;
509 
510 	uobj = container_of(event->element.qp->uobject,
511 			    struct ib_uevent_object, uobject);
512 
513 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
514 				event->event, &uobj->event_list,
515 				&uobj->events_reported);
516 }
517 
518 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
519 {
520 	struct ib_uevent_object *uobj;
521 
522 	uobj = container_of(event->element.srq->uobject,
523 			    struct ib_uevent_object, uobject);
524 
525 	ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
526 				event->event, &uobj->event_list,
527 				&uobj->events_reported);
528 }
529 
530 void ib_uverbs_event_handler(struct ib_event_handler *handler,
531 			     struct ib_event *event)
532 {
533 	struct ib_uverbs_file *file =
534 		container_of(handler, struct ib_uverbs_file, event_handler);
535 
536 	ib_uverbs_async_handler(file, event->element.port_num, event->event,
537 				NULL, NULL);
538 }
539 
540 struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
541 					int is_async)
542 {
543 	struct ib_uverbs_event_file *ev_file;
544 	struct file *filp;
545 
546 	ev_file = kmalloc(sizeof *ev_file, GFP_KERNEL);
547 	if (!ev_file)
548 		return ERR_PTR(-ENOMEM);
549 
550 	kref_init(&ev_file->ref);
551 	spin_lock_init(&ev_file->lock);
552 	INIT_LIST_HEAD(&ev_file->event_list);
553 	init_waitqueue_head(&ev_file->poll_wait);
554 	ev_file->uverbs_file = uverbs_file;
555 	ev_file->async_queue = NULL;
556 	ev_file->is_async    = is_async;
557 	ev_file->is_closed   = 0;
558 
559 	filp = anon_inode_getfile("[infinibandevent]", &uverbs_event_fops,
560 				  ev_file, O_RDONLY);
561 	if (IS_ERR(filp))
562 		kfree(ev_file);
563 
564 	return filp;
565 }
566 
567 /*
568  * Look up a completion event file by FD.  If lookup is successful,
569  * takes a ref to the event file struct that it returns; if
570  * unsuccessful, returns NULL.
571  */
572 struct ib_uverbs_event_file *ib_uverbs_lookup_comp_file(int fd)
573 {
574 	struct ib_uverbs_event_file *ev_file = NULL;
575 	struct fd f = fdget(fd);
576 
577 	if (!f.file)
578 		return NULL;
579 
580 	if (f.file->f_op != &uverbs_event_fops)
581 		goto out;
582 
583 	ev_file = f.file->private_data;
584 	if (ev_file->is_async) {
585 		ev_file = NULL;
586 		goto out;
587 	}
588 
589 	kref_get(&ev_file->ref);
590 
591 out:
592 	fdput(f);
593 	return ev_file;
594 }
595 
596 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
597 			     size_t count, loff_t *pos)
598 {
599 	struct ib_uverbs_file *file = filp->private_data;
600 	struct ib_uverbs_cmd_hdr hdr;
601 	__u32 flags;
602 
603 	if (count < sizeof hdr)
604 		return -EINVAL;
605 
606 	if (copy_from_user(&hdr, buf, sizeof hdr))
607 		return -EFAULT;
608 
609 	flags = (hdr.command &
610 		 IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
611 
612 	if (!flags) {
613 		__u32 command;
614 
615 		if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
616 					   IB_USER_VERBS_CMD_COMMAND_MASK))
617 			return -EINVAL;
618 
619 		command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
620 
621 		if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
622 		    !uverbs_cmd_table[command])
623 			return -EINVAL;
624 
625 		if (!file->ucontext &&
626 		    command != IB_USER_VERBS_CMD_GET_CONTEXT)
627 			return -EINVAL;
628 
629 		if (!(file->device->ib_dev->uverbs_cmd_mask & (1ull << command)))
630 			return -ENOSYS;
631 
632 		if (hdr.in_words * 4 != count)
633 			return -EINVAL;
634 
635 		return uverbs_cmd_table[command](file,
636 						 buf + sizeof(hdr),
637 						 hdr.in_words * 4,
638 						 hdr.out_words * 4);
639 
640 	} else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
641 		__u32 command;
642 
643 		struct ib_uverbs_ex_cmd_hdr ex_hdr;
644 		struct ib_udata ucore;
645 		struct ib_udata uhw;
646 		int err;
647 		size_t written_count = count;
648 
649 		if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
650 					   IB_USER_VERBS_CMD_COMMAND_MASK))
651 			return -EINVAL;
652 
653 		command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
654 
655 		if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
656 		    !uverbs_ex_cmd_table[command])
657 			return -ENOSYS;
658 
659 		if (!file->ucontext)
660 			return -EINVAL;
661 
662 		if (!(file->device->ib_dev->uverbs_ex_cmd_mask & (1ull << command)))
663 			return -ENOSYS;
664 
665 		if (count < (sizeof(hdr) + sizeof(ex_hdr)))
666 			return -EINVAL;
667 
668 		if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr)))
669 			return -EFAULT;
670 
671 		count -= sizeof(hdr) + sizeof(ex_hdr);
672 		buf += sizeof(hdr) + sizeof(ex_hdr);
673 
674 		if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count)
675 			return -EINVAL;
676 
677 		if (ex_hdr.cmd_hdr_reserved)
678 			return -EINVAL;
679 
680 		if (ex_hdr.response) {
681 			if (!hdr.out_words && !ex_hdr.provider_out_words)
682 				return -EINVAL;
683 
684 			if (!access_ok(VERIFY_WRITE,
685 				       (void __user *) (unsigned long) ex_hdr.response,
686 				       (hdr.out_words + ex_hdr.provider_out_words) * 8))
687 				return -EFAULT;
688 		} else {
689 			if (hdr.out_words || ex_hdr.provider_out_words)
690 				return -EINVAL;
691 		}
692 
693 		INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
694 				       hdr.in_words * 8, hdr.out_words * 8);
695 
696 		INIT_UDATA_BUF_OR_NULL(&uhw,
697 				       buf + ucore.inlen,
698 				       (unsigned long) ex_hdr.response + ucore.outlen,
699 				       ex_hdr.provider_in_words * 8,
700 				       ex_hdr.provider_out_words * 8);
701 
702 		err = uverbs_ex_cmd_table[command](file,
703 						   &ucore,
704 						   &uhw);
705 
706 		if (err)
707 			return err;
708 
709 		return written_count;
710 	}
711 
712 	return -ENOSYS;
713 }
714 
715 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
716 {
717 	struct ib_uverbs_file *file = filp->private_data;
718 
719 	if (!file->ucontext)
720 		return -ENODEV;
721 	else
722 		return file->device->ib_dev->mmap(file->ucontext, vma);
723 }
724 
725 /*
726  * ib_uverbs_open() does not need the BKL:
727  *
728  *  - the ib_uverbs_device structures are properly reference counted and
729  *    everything else is purely local to the file being created, so
730  *    races against other open calls are not a problem;
731  *  - there is no ioctl method to race against;
732  *  - the open method will either immediately run -ENXIO, or all
733  *    required initialization will be done.
734  */
735 static int ib_uverbs_open(struct inode *inode, struct file *filp)
736 {
737 	struct ib_uverbs_device *dev;
738 	struct ib_uverbs_file *file;
739 	int ret;
740 
741 	dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
742 	if (dev)
743 		kref_get(&dev->ref);
744 	else
745 		return -ENXIO;
746 
747 	if (!try_module_get(dev->ib_dev->owner)) {
748 		ret = -ENODEV;
749 		goto err;
750 	}
751 
752 	file = kmalloc(sizeof *file, GFP_KERNEL);
753 	if (!file) {
754 		ret = -ENOMEM;
755 		goto err_module;
756 	}
757 
758 	file->device	 = dev;
759 	file->ucontext	 = NULL;
760 	file->async_file = NULL;
761 	kref_init(&file->ref);
762 	mutex_init(&file->mutex);
763 
764 	filp->private_data = file;
765 
766 	return nonseekable_open(inode, filp);
767 
768 err_module:
769 	module_put(dev->ib_dev->owner);
770 
771 err:
772 	kref_put(&dev->ref, ib_uverbs_release_dev);
773 	return ret;
774 }
775 
776 static int ib_uverbs_close(struct inode *inode, struct file *filp)
777 {
778 	struct ib_uverbs_file *file = filp->private_data;
779 
780 	ib_uverbs_cleanup_ucontext(file, file->ucontext);
781 
782 	if (file->async_file)
783 		kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
784 
785 	kref_put(&file->ref, ib_uverbs_release_file);
786 
787 	return 0;
788 }
789 
790 static const struct file_operations uverbs_fops = {
791 	.owner	 = THIS_MODULE,
792 	.write	 = ib_uverbs_write,
793 	.open	 = ib_uverbs_open,
794 	.release = ib_uverbs_close,
795 	.llseek	 = no_llseek,
796 };
797 
798 static const struct file_operations uverbs_mmap_fops = {
799 	.owner	 = THIS_MODULE,
800 	.write	 = ib_uverbs_write,
801 	.mmap    = ib_uverbs_mmap,
802 	.open	 = ib_uverbs_open,
803 	.release = ib_uverbs_close,
804 	.llseek	 = no_llseek,
805 };
806 
807 static struct ib_client uverbs_client = {
808 	.name   = "uverbs",
809 	.add    = ib_uverbs_add_one,
810 	.remove = ib_uverbs_remove_one
811 };
812 
813 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
814 			  char *buf)
815 {
816 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
817 
818 	if (!dev)
819 		return -ENODEV;
820 
821 	return sprintf(buf, "%s\n", dev->ib_dev->name);
822 }
823 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
824 
825 static ssize_t show_dev_abi_version(struct device *device,
826 				    struct device_attribute *attr, char *buf)
827 {
828 	struct ib_uverbs_device *dev = dev_get_drvdata(device);
829 
830 	if (!dev)
831 		return -ENODEV;
832 
833 	return sprintf(buf, "%d\n", dev->ib_dev->uverbs_abi_ver);
834 }
835 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
836 
837 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
838 			 __stringify(IB_USER_VERBS_ABI_VERSION));
839 
840 static dev_t overflow_maj;
841 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
842 
843 /*
844  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
845  * requesting a new major number and doubling the number of max devices we
846  * support. It's stupid, but simple.
847  */
848 static int find_overflow_devnum(void)
849 {
850 	int ret;
851 
852 	if (!overflow_maj) {
853 		ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
854 					  "infiniband_verbs");
855 		if (ret) {
856 			printk(KERN_ERR "user_verbs: couldn't register dynamic device number\n");
857 			return ret;
858 		}
859 	}
860 
861 	ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
862 	if (ret >= IB_UVERBS_MAX_DEVICES)
863 		return -1;
864 
865 	return ret;
866 }
867 
868 static void ib_uverbs_add_one(struct ib_device *device)
869 {
870 	int devnum;
871 	dev_t base;
872 	struct ib_uverbs_device *uverbs_dev;
873 
874 	if (!device->alloc_ucontext)
875 		return;
876 
877 	uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
878 	if (!uverbs_dev)
879 		return;
880 
881 	kref_init(&uverbs_dev->ref);
882 	init_completion(&uverbs_dev->comp);
883 	uverbs_dev->xrcd_tree = RB_ROOT;
884 	mutex_init(&uverbs_dev->xrcd_tree_mutex);
885 
886 	spin_lock(&map_lock);
887 	devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
888 	if (devnum >= IB_UVERBS_MAX_DEVICES) {
889 		spin_unlock(&map_lock);
890 		devnum = find_overflow_devnum();
891 		if (devnum < 0)
892 			goto err;
893 
894 		spin_lock(&map_lock);
895 		uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
896 		base = devnum + overflow_maj;
897 		set_bit(devnum, overflow_map);
898 	} else {
899 		uverbs_dev->devnum = devnum;
900 		base = devnum + IB_UVERBS_BASE_DEV;
901 		set_bit(devnum, dev_map);
902 	}
903 	spin_unlock(&map_lock);
904 
905 	uverbs_dev->ib_dev           = device;
906 	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
907 
908 	cdev_init(&uverbs_dev->cdev, NULL);
909 	uverbs_dev->cdev.owner = THIS_MODULE;
910 	uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
911 	kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
912 	if (cdev_add(&uverbs_dev->cdev, base, 1))
913 		goto err_cdev;
914 
915 	uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
916 					uverbs_dev->cdev.dev, uverbs_dev,
917 					"uverbs%d", uverbs_dev->devnum);
918 	if (IS_ERR(uverbs_dev->dev))
919 		goto err_cdev;
920 
921 	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
922 		goto err_class;
923 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
924 		goto err_class;
925 
926 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
927 
928 	return;
929 
930 err_class:
931 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
932 
933 err_cdev:
934 	cdev_del(&uverbs_dev->cdev);
935 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
936 		clear_bit(devnum, dev_map);
937 	else
938 		clear_bit(devnum, overflow_map);
939 
940 err:
941 	kref_put(&uverbs_dev->ref, ib_uverbs_release_dev);
942 	wait_for_completion(&uverbs_dev->comp);
943 	kfree(uverbs_dev);
944 	return;
945 }
946 
947 static void ib_uverbs_remove_one(struct ib_device *device)
948 {
949 	struct ib_uverbs_device *uverbs_dev = ib_get_client_data(device, &uverbs_client);
950 
951 	if (!uverbs_dev)
952 		return;
953 
954 	dev_set_drvdata(uverbs_dev->dev, NULL);
955 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
956 	cdev_del(&uverbs_dev->cdev);
957 
958 	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
959 		clear_bit(uverbs_dev->devnum, dev_map);
960 	else
961 		clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
962 
963 	kref_put(&uverbs_dev->ref, ib_uverbs_release_dev);
964 	wait_for_completion(&uverbs_dev->comp);
965 	kfree(uverbs_dev);
966 }
967 
968 static char *uverbs_devnode(struct device *dev, umode_t *mode)
969 {
970 	if (mode)
971 		*mode = 0666;
972 	return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
973 }
974 
975 static int __init ib_uverbs_init(void)
976 {
977 	int ret;
978 
979 	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
980 				     "infiniband_verbs");
981 	if (ret) {
982 		printk(KERN_ERR "user_verbs: couldn't register device number\n");
983 		goto out;
984 	}
985 
986 	uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
987 	if (IS_ERR(uverbs_class)) {
988 		ret = PTR_ERR(uverbs_class);
989 		printk(KERN_ERR "user_verbs: couldn't create class infiniband_verbs\n");
990 		goto out_chrdev;
991 	}
992 
993 	uverbs_class->devnode = uverbs_devnode;
994 
995 	ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
996 	if (ret) {
997 		printk(KERN_ERR "user_verbs: couldn't create abi_version attribute\n");
998 		goto out_class;
999 	}
1000 
1001 	ret = ib_register_client(&uverbs_client);
1002 	if (ret) {
1003 		printk(KERN_ERR "user_verbs: couldn't register client\n");
1004 		goto out_class;
1005 	}
1006 
1007 	return 0;
1008 
1009 out_class:
1010 	class_destroy(uverbs_class);
1011 
1012 out_chrdev:
1013 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1014 
1015 out:
1016 	return ret;
1017 }
1018 
1019 static void __exit ib_uverbs_cleanup(void)
1020 {
1021 	ib_unregister_client(&uverbs_client);
1022 	class_destroy(uverbs_class);
1023 	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1024 	if (overflow_maj)
1025 		unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1026 	idr_destroy(&ib_uverbs_pd_idr);
1027 	idr_destroy(&ib_uverbs_mr_idr);
1028 	idr_destroy(&ib_uverbs_mw_idr);
1029 	idr_destroy(&ib_uverbs_ah_idr);
1030 	idr_destroy(&ib_uverbs_cq_idr);
1031 	idr_destroy(&ib_uverbs_qp_idr);
1032 	idr_destroy(&ib_uverbs_srq_idr);
1033 }
1034 
1035 module_init(ib_uverbs_init);
1036 module_exit(ib_uverbs_cleanup);
1037