summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/drm_fops.c
blob: 309023f12d7ff7ab5413baf14af4f580c2a5ccbc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
/**
 * \file drm_fops.c
 * File operations for DRM
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Daryll Strauss <daryll@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 */

/*
 * Created: Mon Jan  4 08:58:31 1999 by faith@valinux.com
 *
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include <drm/drmP.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>

/* from BKL pushdown: note that nothing else serializes idr_find() */
DEFINE_MUTEX(drm_global_mutex);
EXPORT_SYMBOL(drm_global_mutex);

static int drm_open_helper(struct inode *inode, struct file *filp,
			   struct drm_device * dev);

static int drm_setup(struct drm_device * dev)
{
	int ret;

	if (dev->driver->firstopen &&
	    !drm_core_check_feature(dev, DRIVER_MODESET)) {
		ret = dev->driver->firstopen(dev);
		if (ret != 0)
			return ret;
	}

	ret = drm_legacy_dma_setup(dev);
	if (ret < 0)
		return ret;


	DRM_DEBUG("\n");
	return 0;
}

/**
 * Open file.
 *
 * \param inode device inode
 * \param filp file pointer.
 * \return zero on success or a negative number on failure.
 *
 * Searches the DRM device with the same minor number, calls open_helper(), and
 * increments the device open count. If the open count was previous at zero,
 * i.e., it's the first that the device is open, then calls setup().
 */
int drm_open(struct inode *inode, struct file *filp)
{
	struct drm_device *dev = NULL;
	int minor_id = iminor(inode);
	struct drm_minor *minor;
	int retcode = 0;
	int need_setup = 0;
	struct address_space *old_mapping;
	struct address_space *old_imapping;

	minor = idr_find(&drm_minors_idr, minor_id);
	if (!minor)
		return -ENODEV;

	if (!(dev = minor->dev))
		return -ENODEV;

	if (drm_device_is_unplugged(dev))
		return -ENODEV;

	if (!dev->open_count++)
		need_setup = 1;
	mutex_lock(&dev->struct_mutex);
	old_imapping = inode->i_mapping;
	old_mapping = dev->dev_mapping;
	if (old_mapping == NULL)
		dev->dev_mapping = &inode->i_data;
	/* ihold ensures nobody can remove inode with our i_data */
	ihold(container_of(dev->dev_mapping, struct inode, i_data));
	inode->i_mapping = dev->dev_mapping;
	filp->f_mapping = dev->dev_mapping;
	mutex_unlock(&dev->struct_mutex);

	retcode = drm_open_helper(inode, filp, dev);
	if (retcode)
		goto err_undo;
	if (need_setup) {
		retcode = drm_setup(dev);
		if (retcode)
			goto err_undo;
	}
	return 0;

err_undo:
	mutex_lock(&dev->struct_mutex);
	filp->f_mapping = old_imapping;
	inode->i_mapping = old_imapping;
	iput(container_of(dev->dev_mapping, struct inode, i_data));
	dev->dev_mapping = old_mapping;
	mutex_unlock(&dev->struct_mutex);
	dev->open_count--;
	return retcode;
}
EXPORT_SYMBOL(drm_open);

/**
 * File \c open operation.
 *
 * \param inode device inode.
 * \param filp file pointer.
 *
 * Puts the dev->fops corresponding to the device minor number into
 * \p filp, call the \c open method, and restore the file operations.
 */
int drm_stub_open(struct inode *inode, struct file *filp)
{
	struct drm_device *dev = NULL;
	struct drm_minor *minor;
	int minor_id = iminor(inode);
	int err = -ENODEV;
	const struct file_operations *new_fops;

	DRM_DEBUG("\n");

	mutex_lock(&drm_global_mutex);
	minor = idr_find(&drm_minors_idr, minor_id);
	if (!minor)
		goto out;

	if (!(dev = minor->dev))
		goto out;

	if (drm_device_is_unplugged(dev))
		goto out;

	new_fops = fops_get(dev->driver->fops);
	if (!new_fops)
		goto out;

	replace_fops(filp, new_fops);
	if (filp->f_op->open)
		err = filp->f_op->open(inode, filp);
out:
	mutex_unlock(&drm_global_mutex);
	return err;
}

/**
 * Check whether DRI will run on this CPU.
 *
 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 */
static int drm_cpu_valid(void)
{
#if defined(__i386__)
	if (boot_cpu_data.x86 == 3)
		return 0;	/* No cmpxchg on a 386 */
#endif
#if defined(__sparc__) && !defined(__sparc_v9__)
	return 0;		/* No cmpxchg before v9 sparc. */
#endif
	return 1;
}

/**
 * Called whenever a process opens /dev/drm.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param dev device.
 * \return zero on success or a negative number on failure.
 *
 * Creates and initializes a drm_file structure for the file private data in \p
 * filp and add it into the double linked list in \p dev.
 */
static int drm_open_helper(struct inode *inode, struct file *filp,
			   struct drm_device * dev)
{
	int minor_id = iminor(inode);
	struct drm_file *priv;
	int ret;

	if (filp->f_flags & O_EXCL)
		return -EBUSY;	/* No exclusive opens */
	if (!drm_cpu_valid())
		return -EINVAL;
	if (dev->switch_power_state != DRM_SWITCH_POWER_ON && dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
		return -EINVAL;

	DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id);

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	filp->private_data = priv;
	priv->filp = filp;
	priv->uid = current_euid();
	priv->pid = get_pid(task_pid(current));
	priv->minor = idr_find(&drm_minors_idr, minor_id);
	if (!priv->minor) {
		ret = -ENODEV;
		goto out_put_pid;
	}

	/* for compatibility root is always authenticated */
	priv->always_authenticated = capable(CAP_SYS_ADMIN);
	priv->authenticated = priv->always_authenticated;
	priv->lock_count = 0;

	INIT_LIST_HEAD(&priv->lhead);
	INIT_LIST_HEAD(&priv->fbs);
	mutex_init(&priv->fbs_lock);
	INIT_LIST_HEAD(&priv->event_list);
	init_waitqueue_head(&priv->event_wait);
	priv->event_space = 4096; /* set aside 4k for event buffer */

	if (dev->driver->driver_features & DRIVER_GEM)
		drm_gem_open(dev, priv);

	if (drm_core_check_feature(dev, DRIVER_PRIME))
		drm_prime_init_file_private(&priv->prime);

	if (dev->driver->open) {
		ret = dev->driver->open(dev, priv);
		if (ret < 0)
			goto out_prime_destroy;
	}

	/* if there is no current master make this fd it, but do not create
	 * any master object for render clients */
	mutex_lock(&dev->struct_mutex);
	if (!priv->minor->master && !drm_is_render_client(priv)) {
		/* create a new master */
		priv->minor->master = drm_master_create(priv->minor);
		if (!priv->minor->master) {
			mutex_unlock(&dev->struct_mutex);
			ret = -ENOMEM;
			goto out_close;
		}

		priv->is_master = 1;
		/* take another reference for the copy in the local file priv */
		priv->master = drm_master_get(priv->minor->master);

		priv->authenticated = 1;

		mutex_unlock(&dev->struct_mutex);
		if (dev->driver->master_create) {
			ret = dev->driver->master_create(dev, priv->master);
			if (ret) {
				mutex_lock(&dev->struct_mutex);
				/* drop both references if this fails */
				drm_master_put(&priv->minor->master);
				drm_master_put(&priv->master);
				mutex_unlock(&dev->struct_mutex);
				goto out_close;
			}
		}
		mutex_lock(&dev->struct_mutex);
		if (dev->driver->master_set) {
			ret = dev->driver->master_set(dev, priv, true);
			if (ret) {
				/* drop both references if this fails */
				drm_master_put(&priv->minor->master);
				drm_master_put(&priv->master);
				mutex_unlock(&dev->struct_mutex);
				goto out_close;
			}
		}
	} else if (!drm_is_render_client(priv)) {
		/* get a reference to the master */
		priv->master = drm_master_get(priv->minor->master);
	}
	mutex_unlock(&dev->struct_mutex);

	mutex_lock(&dev->struct_mutex);
	list_add(&priv->lhead, &dev->filelist);
	mutex_unlock(&dev->struct_mutex);

#ifdef __alpha__
	/*
	 * Default the hose
	 */
	if (!dev->hose) {
		struct pci_dev *pci_dev;
		pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
		if (pci_dev) {
			dev->hose = pci_dev->sysdata;
			pci_dev_put(pci_dev);
		}
		if (!dev->hose) {
			struct pci_bus *b = list_entry(pci_root_buses.next,
				struct pci_bus, node);
			if (b)
				dev->hose = b->sysdata;
		}
	}
#endif

	return 0;

out_close:
	if (dev->driver->postclose)
		dev->driver->postclose(dev, priv);
out_prime_destroy:
	if (drm_core_check_feature(dev, DRIVER_PRIME))
		drm_prime_destroy_file_private(&priv->prime);
	if (dev->driver->driver_features & DRIVER_GEM)
		drm_gem_release(dev, priv);
out_put_pid:
	put_pid(priv->pid);
	kfree(priv);
	filp->private_data = NULL;
	return ret;
}

static void drm_master_release(struct drm_device *dev, struct file *filp)
{
	struct drm_file *file_priv = filp->private_data;

	if (drm_i_have_hw_lock(dev, file_priv)) {
		DRM_DEBUG("File %p released, freeing lock for context %d\n",
			  filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
		drm_lock_free(&file_priv->master->lock,
			      _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
	}
}

static void drm_events_release(struct drm_file *file_priv)
{
	struct drm_device *dev = file_priv->minor->dev;
	struct drm_pending_event *e, *et;
	struct drm_pending_vblank_event *v, *vt;
	unsigned long flags;

	spin_lock_irqsave(&dev->event_lock, flags);

	/* Remove pending flips */
	list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link)
		if (v->base.file_priv == file_priv) {
			list_del(&v->base.link);
			drm_vblank_put(dev, v->pipe);
			v->base.destroy(&v->base);
		}

	/* Remove unconsumed events */
	list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
		list_del(&e->link);
		e->destroy(e);
	}

	spin_unlock_irqrestore(&dev->event_lock, flags);
}

/**
 * drm_legacy_dev_reinit
 *
 * Reinitializes a legacy/ums drm device in it's lastclose function.
 */
static void drm_legacy_dev_reinit(struct drm_device *dev)
{
	if (drm_core_check_feature(dev, DRIVER_MODESET))
		return;

	dev->sigdata.lock = NULL;

	dev->context_flag = 0;
	dev->last_context = 0;
	dev->if_version = 0;
}

/**
 * Take down the DRM device.
 *
 * \param dev DRM device structure.
 *
 * Frees every resource in \p dev.
 *
 * \sa drm_device
 */
int drm_lastclose(struct drm_device * dev)
{
	struct drm_vma_entry *vma, *vma_temp;

	DRM_DEBUG("\n");

	if (dev->driver->lastclose)
		dev->driver->lastclose(dev);
	DRM_DEBUG("driver lastclose completed\n");

	if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
		drm_irq_uninstall(dev);

	mutex_lock(&dev->struct_mutex);

	drm_agp_clear(dev);

	drm_legacy_sg_cleanup(dev);

	/* Clear vma list (only built for debugging) */
	list_for_each_entry_safe(vma, vma_temp, &dev->vmalist, head) {
		list_del(&vma->head);
		kfree(vma);
	}

	drm_legacy_dma_takedown(dev);

	dev->dev_mapping = NULL;
	mutex_unlock(&dev->struct_mutex);

	drm_legacy_dev_reinit(dev);

	DRM_DEBUG("lastclose completed\n");
	return 0;
}

/**
 * Release file.
 *
 * \param inode device inode
 * \param file_priv DRM file private.
 * \return zero on success or a negative number on failure.
 *
 * If the hardware lock is held then free it, and take it again for the kernel
 * context since it's necessary to reclaim buffers. Unlink the file private
 * data from its list and free it. Decreases the open count and if it reaches
 * zero calls drm_lastclose().
 */
int drm_release(struct inode *inode, struct file *filp)
{
	struct drm_file *file_priv = filp->private_data;
	struct drm_device *dev = file_priv->minor->dev;
	int retcode = 0;

	mutex_lock(&drm_global_mutex);

	DRM_DEBUG("open_count = %d\n", dev->open_count);

	if (dev->driver->preclose)
		dev->driver->preclose(dev, file_priv);

	/* ========================================================
	 * Begin inline drm_release
	 */

	DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
		  task_pid_nr(current),
		  (long)old_encode_dev(file_priv->minor->device),
		  dev->open_count);

	/* Release any auth tokens that might point to this file_priv,
	   (do that under the drm_global_mutex) */
	if (file_priv->magic)
		(void) drm_remove_magic(file_priv->master, file_priv->magic);

	/* if the master has gone away we can't do anything with the lock */
	if (file_priv->minor->master)
		drm_master_release(dev, filp);

	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
		drm_core_reclaim_buffers(dev, file_priv);

	drm_events_release(file_priv);

	if (dev->driver->driver_features & DRIVER_MODESET)
		drm_fb_release(file_priv);

	if (dev->driver->driver_features & DRIVER_GEM)
		drm_gem_release(dev, file_priv);

	mutex_lock(&dev->ctxlist_mutex);
	if (!list_empty(&dev->ctxlist)) {
		struct drm_ctx_list *pos, *n;

		list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
			if (pos->tag == file_priv &&
			    pos->handle != DRM_KERNEL_CONTEXT) {
				if (dev->driver->context_dtor)
					dev->driver->context_dtor(dev,
								  pos->handle);

				drm_ctxbitmap_free(dev, pos->handle);

				list_del(&pos->head);
				kfree(pos);
			}
		}
	}
	mutex_unlock(&dev->ctxlist_mutex);

	mutex_lock(&dev->struct_mutex);

	if (file_priv->is_master) {
		struct drm_master *master = file_priv->master;
		struct drm_file *temp;
		list_for_each_entry(temp, &dev->filelist, lhead) {
			if ((temp->master == file_priv->master) &&
			    (temp != file_priv))
				temp->authenticated = temp->always_authenticated;
		}

		/**
		 * Since the master is disappearing, so is the
		 * possibility to lock.
		 */

		if (master->lock.hw_lock) {
			if (dev->sigdata.lock == master->lock.hw_lock)
				dev->sigdata.lock = NULL;
			master->lock.hw_lock = NULL;
			master->lock.file_priv = NULL;
			wake_up_interruptible_all(&master->lock.lock_queue);
		}

		if (file_priv->minor->master == file_priv->master) {
			/* drop the reference held my the minor */
			if (dev->driver->master_drop)
				dev->driver->master_drop(dev, file_priv, true);
			drm_master_put(&file_priv->minor->master);
		}
	}

	BUG_ON(dev->dev_mapping == NULL);
	iput(container_of(dev->dev_mapping, struct inode, i_data));

	/* drop the reference held my the file priv */
	if (file_priv->master)
		drm_master_put(&file_priv->master);
	file_priv->is_master = 0;
	list_del(&file_priv->lhead);
	mutex_unlock(&dev->struct_mutex);

	if (dev->driver->postclose)
		dev->driver->postclose(dev, file_priv);


	if (drm_core_check_feature(dev, DRIVER_PRIME))
		drm_prime_destroy_file_private(&file_priv->prime);

	put_pid(file_priv->pid);
	kfree(file_priv);

	/* ========================================================
	 * End inline drm_release
	 */

	if (!--dev->open_count) {
		retcode = drm_lastclose(dev);
		if (drm_device_is_unplugged(dev))
			drm_put_dev(dev);
	}
	mutex_unlock(&drm_global_mutex);

	return retcode;
}
EXPORT_SYMBOL(drm_release);

static bool
drm_dequeue_event(struct drm_file *file_priv,
		  size_t total, size_t max, struct drm_pending_event **out)
{
	struct drm_device *dev = file_priv->minor->dev;
	struct drm_pending_event *e;
	unsigned long flags;
	bool ret = false;

	spin_lock_irqsave(&dev->event_lock, flags);

	*out = NULL;
	if (list_empty(&file_priv->event_list))
		goto out;
	e = list_first_entry(&file_priv->event_list,
			     struct drm_pending_event, link);
	if (e->event->length + total > max)
		goto out;

	file_priv->event_space += e->event->length;
	list_del(&e->link);
	*out = e;
	ret = true;

out:
	spin_unlock_irqrestore(&dev->event_lock, flags);
	return ret;
}

ssize_t drm_read(struct file *filp, char __user *buffer,
		 size_t count, loff_t *offset)
{
	struct drm_file *file_priv = filp->private_data;
	struct drm_pending_event *e;
	size_t total;
	ssize_t ret;

	ret = wait_event_interruptible(file_priv->event_wait,
				       !list_empty(&file_priv->event_list));
	if (ret < 0)
		return ret;

	total = 0;
	while (drm_dequeue_event(file_priv, total, count, &e)) {
		if (copy_to_user(buffer + total,
				 e->event, e->event->length)) {
			total = -EFAULT;
			break;
		}

		total += e->event->length;
		e->destroy(e);
	}

	return total;
}
EXPORT_SYMBOL(drm_read);

unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
{
	struct drm_file *file_priv = filp->private_data;
	unsigned int mask = 0;

	poll_wait(filp, &file_priv->event_wait, wait);

	if (!list_empty(&file_priv->event_list))
		mask |= POLLIN | POLLRDNORM;

	return mask;
}
EXPORT_SYMBOL(drm_poll);