1 /*
2 * Created: Fri Jan 19 10:48:35 2001 by faith@acm.org
3 *
4 * Copyright 2001 VA Linux Systems, Inc., Sunnyvale, California.
5 * All Rights Reserved.
6 *
7 * Author Rickard E. (Rik) Faith <faith@valinux.com>
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a
10 * copy of this software and associated documentation files (the "Software"),
11 * to deal in the Software without restriction, including without limitation
12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13 * and/or sell copies of the Software, and to permit persons to whom the
14 * Software is furnished to do so, subject to the following conditions:
15 *
16 * The above copyright notice and this permission notice (including the next
17 * paragraph) shall be included in all copies or substantial portions of the
18 * Software.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
24 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26 * DEALINGS IN THE SOFTWARE.
27 */
28
29 #include <linux/debugfs.h>
30 #include <linux/fs.h>
31 #include <linux/module.h>
32 #include <linux/moduleparam.h>
33 #include <linux/mount.h>
34 #include <linux/slab.h>
35 #include <drm/drmP.h>
36 #include <drm/drm_core.h>
37 #include "drm_legacy.h"
38 #include "drm_internal.h"
39
40 unsigned int drm_debug = 0; /* bitmask of DRM_UT_x */
41 EXPORT_SYMBOL(drm_debug);
42
43 MODULE_AUTHOR(CORE_AUTHOR);
44 MODULE_DESCRIPTION(CORE_DESC);
45 MODULE_LICENSE("GPL and additional rights");
46 MODULE_PARM_DESC(debug, "Enable debug output");
47 MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)");
48 MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]");
49 MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps");
50
51 module_param_named(debug, drm_debug, int, 0600);
52
53 static DEFINE_SPINLOCK(drm_minor_lock);
54 static struct idr drm_minors_idr;
55
56 static struct dentry *drm_debugfs_root;
57
drm_err(const char * format,...)58 void drm_err(const char *format, ...)
59 {
60 struct va_format vaf;
61 va_list args;
62
63 va_start(args, format);
64
65 vaf.fmt = format;
66 vaf.va = &args;
67
68 printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV",
69 __builtin_return_address(0), &vaf);
70
71 va_end(args);
72 }
73 EXPORT_SYMBOL(drm_err);
74
drm_ut_debug_printk(const char * function_name,const char * format,...)75 void drm_ut_debug_printk(const char *function_name, const char *format, ...)
76 {
77 struct va_format vaf;
78 va_list args;
79
80 va_start(args, format);
81 vaf.fmt = format;
82 vaf.va = &args;
83
84 printk(KERN_DEBUG "[" DRM_NAME ":%s] %pV", function_name, &vaf);
85
86 va_end(args);
87 }
88 EXPORT_SYMBOL(drm_ut_debug_printk);
89
drm_master_create(struct drm_minor * minor)90 struct drm_master *drm_master_create(struct drm_minor *minor)
91 {
92 struct drm_master *master;
93
94 master = kzalloc(sizeof(*master), GFP_KERNEL);
95 if (!master)
96 return NULL;
97
98 kref_init(&master->refcount);
99 spin_lock_init(&master->lock.spinlock);
100 init_waitqueue_head(&master->lock.lock_queue);
101 idr_init(&master->magic_map);
102 master->minor = minor;
103
104 return master;
105 }
106
drm_master_get(struct drm_master * master)107 struct drm_master *drm_master_get(struct drm_master *master)
108 {
109 kref_get(&master->refcount);
110 return master;
111 }
112 EXPORT_SYMBOL(drm_master_get);
113
drm_master_destroy(struct kref * kref)114 static void drm_master_destroy(struct kref *kref)
115 {
116 struct drm_master *master = container_of(kref, struct drm_master, refcount);
117 struct drm_device *dev = master->minor->dev;
118 struct drm_map_list *r_list, *list_temp;
119
120 mutex_lock(&dev->struct_mutex);
121 if (dev->driver->master_destroy)
122 dev->driver->master_destroy(dev, master);
123
124 list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
125 if (r_list->master == master) {
126 drm_legacy_rmmap_locked(dev, r_list->map);
127 r_list = NULL;
128 }
129 }
130 mutex_unlock(&dev->struct_mutex);
131
132 idr_destroy(&master->magic_map);
133 kfree(master->unique);
134 kfree(master);
135 }
136
drm_master_put(struct drm_master ** master)137 void drm_master_put(struct drm_master **master)
138 {
139 kref_put(&(*master)->refcount, drm_master_destroy);
140 *master = NULL;
141 }
142 EXPORT_SYMBOL(drm_master_put);
143
drm_setmaster_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)144 int drm_setmaster_ioctl(struct drm_device *dev, void *data,
145 struct drm_file *file_priv)
146 {
147 int ret = 0;
148
149 mutex_lock(&dev->master_mutex);
150 if (file_priv->is_master)
151 goto out_unlock;
152
153 if (file_priv->minor->master) {
154 ret = -EINVAL;
155 goto out_unlock;
156 }
157
158 if (!file_priv->master) {
159 ret = -EINVAL;
160 goto out_unlock;
161 }
162
163 if (!file_priv->allowed_master) {
164 ret = drm_new_set_master(dev, file_priv);
165 goto out_unlock;
166 }
167
168 file_priv->minor->master = drm_master_get(file_priv->master);
169 file_priv->is_master = 1;
170 if (dev->driver->master_set) {
171 ret = dev->driver->master_set(dev, file_priv, false);
172 if (unlikely(ret != 0)) {
173 file_priv->is_master = 0;
174 drm_master_put(&file_priv->minor->master);
175 }
176 }
177
178 out_unlock:
179 mutex_unlock(&dev->master_mutex);
180 return ret;
181 }
182
drm_dropmaster_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)183 int drm_dropmaster_ioctl(struct drm_device *dev, void *data,
184 struct drm_file *file_priv)
185 {
186 int ret = -EINVAL;
187
188 mutex_lock(&dev->master_mutex);
189 if (!file_priv->is_master)
190 goto out_unlock;
191
192 if (!file_priv->minor->master)
193 goto out_unlock;
194
195 ret = 0;
196 if (dev->driver->master_drop)
197 dev->driver->master_drop(dev, file_priv, false);
198 drm_master_put(&file_priv->minor->master);
199 file_priv->is_master = 0;
200
201 out_unlock:
202 mutex_unlock(&dev->master_mutex);
203 return ret;
204 }
205
206 /*
207 * DRM Minors
208 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
209 * of them is represented by a drm_minor object. Depending on the capabilities
210 * of the device-driver, different interfaces are registered.
211 *
212 * Minors can be accessed via dev->$minor_name. This pointer is either
213 * NULL or a valid drm_minor pointer and stays valid as long as the device is
214 * valid. This means, DRM minors have the same life-time as the underlying
215 * device. However, this doesn't mean that the minor is active. Minors are
216 * registered and unregistered dynamically according to device-state.
217 */
218
drm_minor_get_slot(struct drm_device * dev,unsigned int type)219 static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
220 unsigned int type)
221 {
222 switch (type) {
223 case DRM_MINOR_LEGACY:
224 return &dev->primary;
225 case DRM_MINOR_RENDER:
226 return &dev->render;
227 case DRM_MINOR_CONTROL:
228 return &dev->control;
229 default:
230 return NULL;
231 }
232 }
233
drm_minor_alloc(struct drm_device * dev,unsigned int type)234 static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
235 {
236 struct drm_minor *minor;
237 unsigned long flags;
238 int r;
239
240 minor = kzalloc(sizeof(*minor), GFP_KERNEL);
241 if (!minor)
242 return -ENOMEM;
243
244 minor->type = type;
245 minor->dev = dev;
246
247 idr_preload(GFP_KERNEL);
248 spin_lock_irqsave(&drm_minor_lock, flags);
249 r = idr_alloc(&drm_minors_idr,
250 NULL,
251 64 * type,
252 64 * (type + 1),
253 GFP_NOWAIT);
254 spin_unlock_irqrestore(&drm_minor_lock, flags);
255 idr_preload_end();
256
257 if (r < 0)
258 goto err_free;
259
260 minor->index = r;
261
262 minor->kdev = drm_sysfs_minor_alloc(minor);
263 if (IS_ERR(minor->kdev)) {
264 r = PTR_ERR(minor->kdev);
265 goto err_index;
266 }
267
268 *drm_minor_get_slot(dev, type) = minor;
269 return 0;
270
271 err_index:
272 spin_lock_irqsave(&drm_minor_lock, flags);
273 idr_remove(&drm_minors_idr, minor->index);
274 spin_unlock_irqrestore(&drm_minor_lock, flags);
275 err_free:
276 kfree(minor);
277 return r;
278 }
279
drm_minor_free(struct drm_device * dev,unsigned int type)280 static void drm_minor_free(struct drm_device *dev, unsigned int type)
281 {
282 struct drm_minor **slot, *minor;
283 unsigned long flags;
284
285 slot = drm_minor_get_slot(dev, type);
286 minor = *slot;
287 if (!minor)
288 return;
289
290 put_device(minor->kdev);
291
292 spin_lock_irqsave(&drm_minor_lock, flags);
293 idr_remove(&drm_minors_idr, minor->index);
294 spin_unlock_irqrestore(&drm_minor_lock, flags);
295
296 kfree(minor);
297 *slot = NULL;
298 }
299
drm_minor_register(struct drm_device * dev,unsigned int type)300 static int drm_minor_register(struct drm_device *dev, unsigned int type)
301 {
302 struct drm_minor *minor;
303 unsigned long flags;
304 int ret;
305
306 DRM_DEBUG("\n");
307
308 minor = *drm_minor_get_slot(dev, type);
309 if (!minor)
310 return 0;
311
312 ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root);
313 if (ret) {
314 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
315 goto err_debugfs;
316 }
317
318 ret = device_add(minor->kdev);
319 if (ret)
320 goto err_debugfs;
321
322 /* replace NULL with @minor so lookups will succeed from now on */
323 spin_lock_irqsave(&drm_minor_lock, flags);
324 idr_replace(&drm_minors_idr, minor, minor->index);
325 spin_unlock_irqrestore(&drm_minor_lock, flags);
326
327 DRM_DEBUG("new minor registered %d\n", minor->index);
328 return 0;
329
330 err_debugfs:
331 drm_debugfs_cleanup(minor);
332 return ret;
333 }
334
drm_minor_unregister(struct drm_device * dev,unsigned int type)335 static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
336 {
337 struct drm_minor *minor;
338 unsigned long flags;
339
340 minor = *drm_minor_get_slot(dev, type);
341 if (!minor || !device_is_registered(minor->kdev))
342 return;
343
344 /* replace @minor with NULL so lookups will fail from now on */
345 spin_lock_irqsave(&drm_minor_lock, flags);
346 idr_replace(&drm_minors_idr, NULL, minor->index);
347 spin_unlock_irqrestore(&drm_minor_lock, flags);
348
349 device_del(minor->kdev);
350 dev_set_drvdata(minor->kdev, NULL); /* safety belt */
351 drm_debugfs_cleanup(minor);
352 }
353
354 /**
355 * drm_minor_acquire - Acquire a DRM minor
356 * @minor_id: Minor ID of the DRM-minor
357 *
358 * Looks up the given minor-ID and returns the respective DRM-minor object. The
359 * refence-count of the underlying device is increased so you must release this
360 * object with drm_minor_release().
361 *
362 * As long as you hold this minor, it is guaranteed that the object and the
363 * minor->dev pointer will stay valid! However, the device may get unplugged and
364 * unregistered while you hold the minor.
365 *
366 * Returns:
367 * Pointer to minor-object with increased device-refcount, or PTR_ERR on
368 * failure.
369 */
drm_minor_acquire(unsigned int minor_id)370 struct drm_minor *drm_minor_acquire(unsigned int minor_id)
371 {
372 struct drm_minor *minor;
373 unsigned long flags;
374
375 spin_lock_irqsave(&drm_minor_lock, flags);
376 minor = idr_find(&drm_minors_idr, minor_id);
377 if (minor)
378 drm_dev_ref(minor->dev);
379 spin_unlock_irqrestore(&drm_minor_lock, flags);
380
381 if (!minor) {
382 return ERR_PTR(-ENODEV);
383 } else if (drm_device_is_unplugged(minor->dev)) {
384 drm_dev_unref(minor->dev);
385 return ERR_PTR(-ENODEV);
386 }
387
388 return minor;
389 }
390
391 /**
392 * drm_minor_release - Release DRM minor
393 * @minor: Pointer to DRM minor object
394 *
395 * Release a minor that was previously acquired via drm_minor_acquire().
396 */
drm_minor_release(struct drm_minor * minor)397 void drm_minor_release(struct drm_minor *minor)
398 {
399 drm_dev_unref(minor->dev);
400 }
401
402 /**
403 * DOC: driver instance overview
404 *
405 * A device instance for a drm driver is represented by struct &drm_device. This
406 * is allocated with drm_dev_alloc(), usually from bus-specific ->probe()
407 * callbacks implemented by the driver. The driver then needs to initialize all
408 * the various subsystems for the drm device like memory management, vblank
409 * handling, modesetting support and intial output configuration plus obviously
410 * initialize all the corresponding hardware bits. An important part of this is
411 * also calling drm_dev_set_unique() to set the userspace-visible unique name of
412 * this device instance. Finally when everything is up and running and ready for
413 * userspace the device instance can be published using drm_dev_register().
414 *
415 * There is also deprecated support for initalizing device instances using
416 * bus-specific helpers and the ->load() callback. But due to
417 * backwards-compatibility needs the device instance have to be published too
418 * early, which requires unpretty global locking to make safe and is therefore
419 * only support for existing drivers not yet converted to the new scheme.
420 *
421 * When cleaning up a device instance everything needs to be done in reverse:
422 * First unpublish the device instance with drm_dev_unregister(). Then clean up
423 * any other resources allocated at device initialization and drop the driver's
424 * reference to &drm_device using drm_dev_unref().
425 *
426 * Note that the lifetime rules for &drm_device instance has still a lot of
427 * historical baggage. Hence use the reference counting provided by
428 * drm_dev_ref() and drm_dev_unref() only carefully.
429 *
430 * Also note that embedding of &drm_device is currently not (yet) supported (but
431 * it would be easy to add). Drivers can store driver-private data in the
432 * dev_priv field of &drm_device.
433 */
434
435 /**
436 * drm_put_dev - Unregister and release a DRM device
437 * @dev: DRM device
438 *
439 * Called at module unload time or when a PCI device is unplugged.
440 *
441 * Cleans up all DRM device, calling drm_lastclose().
442 *
443 * Note: Use of this function is deprecated. It will eventually go away
444 * completely. Please use drm_dev_unregister() and drm_dev_unref() explicitly
445 * instead to make sure that the device isn't userspace accessible any more
446 * while teardown is in progress, ensuring that userspace can't access an
447 * inconsistent state.
448 */
drm_put_dev(struct drm_device * dev)449 void drm_put_dev(struct drm_device *dev)
450 {
451 DRM_DEBUG("\n");
452
453 if (!dev) {
454 DRM_ERROR("cleanup called no dev\n");
455 return;
456 }
457
458 drm_dev_unregister(dev);
459 drm_dev_unref(dev);
460 }
461 EXPORT_SYMBOL(drm_put_dev);
462
drm_unplug_dev(struct drm_device * dev)463 void drm_unplug_dev(struct drm_device *dev)
464 {
465 /* for a USB device */
466 drm_minor_unregister(dev, DRM_MINOR_LEGACY);
467 drm_minor_unregister(dev, DRM_MINOR_RENDER);
468 drm_minor_unregister(dev, DRM_MINOR_CONTROL);
469
470 mutex_lock(&drm_global_mutex);
471
472 drm_device_set_unplugged(dev);
473
474 if (dev->open_count == 0) {
475 drm_put_dev(dev);
476 }
477 mutex_unlock(&drm_global_mutex);
478 }
479 EXPORT_SYMBOL(drm_unplug_dev);
480
481 /*
482 * DRM internal mount
483 * We want to be able to allocate our own "struct address_space" to control
484 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
485 * stand-alone address_space objects, so we need an underlying inode. As there
486 * is no way to allocate an independent inode easily, we need a fake internal
487 * VFS mount-point.
488 *
489 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
490 * frees it again. You are allowed to use iget() and iput() to get references to
491 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
492 * drm_fs_inode_free() call (which does not have to be the last iput()).
493 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
494 * between multiple inode-users. You could, technically, call
495 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
496 * iput(), but this way you'd end up with a new vfsmount for each inode.
497 */
498
499 static int drm_fs_cnt;
500 static struct vfsmount *drm_fs_mnt;
501
502 static const struct dentry_operations drm_fs_dops = {
503 .d_dname = simple_dname,
504 };
505
506 static const struct super_operations drm_fs_sops = {
507 .statfs = simple_statfs,
508 };
509
drm_fs_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)510 static struct dentry *drm_fs_mount(struct file_system_type *fs_type, int flags,
511 const char *dev_name, void *data)
512 {
513 return mount_pseudo(fs_type,
514 "drm:",
515 &drm_fs_sops,
516 &drm_fs_dops,
517 0x010203ff);
518 }
519
520 static struct file_system_type drm_fs_type = {
521 .name = "drm",
522 .owner = THIS_MODULE,
523 .mount = drm_fs_mount,
524 .kill_sb = kill_anon_super,
525 };
526
drm_fs_inode_new(void)527 static struct inode *drm_fs_inode_new(void)
528 {
529 struct inode *inode;
530 int r;
531
532 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
533 if (r < 0) {
534 DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
535 return ERR_PTR(r);
536 }
537
538 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
539 if (IS_ERR(inode))
540 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
541
542 return inode;
543 }
544
drm_fs_inode_free(struct inode * inode)545 static void drm_fs_inode_free(struct inode *inode)
546 {
547 if (inode) {
548 iput(inode);
549 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
550 }
551 }
552
553 /**
554 * drm_dev_alloc - Allocate new DRM device
555 * @driver: DRM driver to allocate device for
556 * @parent: Parent device object
557 *
558 * Allocate and initialize a new DRM device. No device registration is done.
559 * Call drm_dev_register() to advertice the device to user space and register it
560 * with other core subsystems. This should be done last in the device
561 * initialization sequence to make sure userspace can't access an inconsistent
562 * state.
563 *
564 * The initial ref-count of the object is 1. Use drm_dev_ref() and
565 * drm_dev_unref() to take and drop further ref-counts.
566 *
567 * Note that for purely virtual devices @parent can be NULL.
568 *
569 * RETURNS:
570 * Pointer to new DRM device, or NULL if out of memory.
571 */
drm_dev_alloc(struct drm_driver * driver,struct device * parent)572 struct drm_device *drm_dev_alloc(struct drm_driver *driver,
573 struct device *parent)
574 {
575 struct drm_device *dev;
576 int ret;
577
578 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
579 if (!dev)
580 return NULL;
581
582 kref_init(&dev->ref);
583 dev->dev = parent;
584 dev->driver = driver;
585
586 INIT_LIST_HEAD(&dev->filelist);
587 INIT_LIST_HEAD(&dev->ctxlist);
588 INIT_LIST_HEAD(&dev->vmalist);
589 INIT_LIST_HEAD(&dev->maplist);
590 INIT_LIST_HEAD(&dev->vblank_event_list);
591
592 spin_lock_init(&dev->buf_lock);
593 spin_lock_init(&dev->event_lock);
594 mutex_init(&dev->struct_mutex);
595 mutex_init(&dev->ctxlist_mutex);
596 mutex_init(&dev->master_mutex);
597
598 dev->anon_inode = drm_fs_inode_new();
599 if (IS_ERR(dev->anon_inode)) {
600 ret = PTR_ERR(dev->anon_inode);
601 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
602 goto err_free;
603 }
604
605 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
606 ret = drm_minor_alloc(dev, DRM_MINOR_CONTROL);
607 if (ret)
608 goto err_minors;
609
610 WARN_ON(driver->suspend || driver->resume);
611 }
612
613 if (drm_core_check_feature(dev, DRIVER_RENDER)) {
614 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
615 if (ret)
616 goto err_minors;
617 }
618
619 ret = drm_minor_alloc(dev, DRM_MINOR_LEGACY);
620 if (ret)
621 goto err_minors;
622
623 if (drm_ht_create(&dev->map_hash, 12))
624 goto err_minors;
625
626 drm_legacy_ctxbitmap_init(dev);
627
628 if (drm_core_check_feature(dev, DRIVER_GEM)) {
629 ret = drm_gem_init(dev);
630 if (ret) {
631 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
632 goto err_ctxbitmap;
633 }
634 }
635
636 return dev;
637
638 err_ctxbitmap:
639 drm_legacy_ctxbitmap_cleanup(dev);
640 drm_ht_remove(&dev->map_hash);
641 err_minors:
642 drm_minor_free(dev, DRM_MINOR_LEGACY);
643 drm_minor_free(dev, DRM_MINOR_RENDER);
644 drm_minor_free(dev, DRM_MINOR_CONTROL);
645 drm_fs_inode_free(dev->anon_inode);
646 err_free:
647 mutex_destroy(&dev->master_mutex);
648 kfree(dev);
649 return NULL;
650 }
651 EXPORT_SYMBOL(drm_dev_alloc);
652
drm_dev_release(struct kref * ref)653 static void drm_dev_release(struct kref *ref)
654 {
655 struct drm_device *dev = container_of(ref, struct drm_device, ref);
656
657 if (drm_core_check_feature(dev, DRIVER_GEM))
658 drm_gem_destroy(dev);
659
660 drm_legacy_ctxbitmap_cleanup(dev);
661 drm_ht_remove(&dev->map_hash);
662 drm_fs_inode_free(dev->anon_inode);
663
664 drm_minor_free(dev, DRM_MINOR_LEGACY);
665 drm_minor_free(dev, DRM_MINOR_RENDER);
666 drm_minor_free(dev, DRM_MINOR_CONTROL);
667
668 mutex_destroy(&dev->master_mutex);
669 kfree(dev->unique);
670 kfree(dev);
671 }
672
673 /**
674 * drm_dev_ref - Take reference of a DRM device
675 * @dev: device to take reference of or NULL
676 *
677 * This increases the ref-count of @dev by one. You *must* already own a
678 * reference when calling this. Use drm_dev_unref() to drop this reference
679 * again.
680 *
681 * This function never fails. However, this function does not provide *any*
682 * guarantee whether the device is alive or running. It only provides a
683 * reference to the object and the memory associated with it.
684 */
drm_dev_ref(struct drm_device * dev)685 void drm_dev_ref(struct drm_device *dev)
686 {
687 if (dev)
688 kref_get(&dev->ref);
689 }
690 EXPORT_SYMBOL(drm_dev_ref);
691
692 /**
693 * drm_dev_unref - Drop reference of a DRM device
694 * @dev: device to drop reference of or NULL
695 *
696 * This decreases the ref-count of @dev by one. The device is destroyed if the
697 * ref-count drops to zero.
698 */
drm_dev_unref(struct drm_device * dev)699 void drm_dev_unref(struct drm_device *dev)
700 {
701 if (dev)
702 kref_put(&dev->ref, drm_dev_release);
703 }
704 EXPORT_SYMBOL(drm_dev_unref);
705
706 /**
707 * drm_dev_register - Register DRM device
708 * @dev: Device to register
709 * @flags: Flags passed to the driver's .load() function
710 *
711 * Register the DRM device @dev with the system, advertise device to user-space
712 * and start normal device operation. @dev must be allocated via drm_dev_alloc()
713 * previously.
714 *
715 * Never call this twice on any device!
716 *
717 * NOTE: To ensure backward compatibility with existing drivers method this
718 * function calls the ->load() method after registering the device nodes,
719 * creating race conditions. Usage of the ->load() methods is therefore
720 * deprecated, drivers must perform all initialization before calling
721 * drm_dev_register().
722 *
723 * RETURNS:
724 * 0 on success, negative error code on failure.
725 */
drm_dev_register(struct drm_device * dev,unsigned long flags)726 int drm_dev_register(struct drm_device *dev, unsigned long flags)
727 {
728 int ret;
729
730 mutex_lock(&drm_global_mutex);
731
732 ret = drm_minor_register(dev, DRM_MINOR_CONTROL);
733 if (ret)
734 goto err_minors;
735
736 ret = drm_minor_register(dev, DRM_MINOR_RENDER);
737 if (ret)
738 goto err_minors;
739
740 ret = drm_minor_register(dev, DRM_MINOR_LEGACY);
741 if (ret)
742 goto err_minors;
743
744 if (dev->driver->load) {
745 ret = dev->driver->load(dev, flags);
746 if (ret)
747 goto err_minors;
748 }
749
750 ret = 0;
751 goto out_unlock;
752
753 err_minors:
754 drm_minor_unregister(dev, DRM_MINOR_LEGACY);
755 drm_minor_unregister(dev, DRM_MINOR_RENDER);
756 drm_minor_unregister(dev, DRM_MINOR_CONTROL);
757 out_unlock:
758 mutex_unlock(&drm_global_mutex);
759 return ret;
760 }
761 EXPORT_SYMBOL(drm_dev_register);
762
763 /**
764 * drm_dev_unregister - Unregister DRM device
765 * @dev: Device to unregister
766 *
767 * Unregister the DRM device from the system. This does the reverse of
768 * drm_dev_register() but does not deallocate the device. The caller must call
769 * drm_dev_unref() to drop their final reference.
770 *
771 * This should be called first in the device teardown code to make sure
772 * userspace can't access the device instance any more.
773 */
drm_dev_unregister(struct drm_device * dev)774 void drm_dev_unregister(struct drm_device *dev)
775 {
776 struct drm_map_list *r_list, *list_temp;
777
778 drm_lastclose(dev);
779
780 if (dev->driver->unload)
781 dev->driver->unload(dev);
782
783 if (dev->agp)
784 drm_pci_agp_destroy(dev);
785
786 drm_vblank_cleanup(dev);
787
788 list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
789 drm_legacy_rmmap(dev, r_list->map);
790
791 drm_minor_unregister(dev, DRM_MINOR_LEGACY);
792 drm_minor_unregister(dev, DRM_MINOR_RENDER);
793 drm_minor_unregister(dev, DRM_MINOR_CONTROL);
794 }
795 EXPORT_SYMBOL(drm_dev_unregister);
796
797 /**
798 * drm_dev_set_unique - Set the unique name of a DRM device
799 * @dev: device of which to set the unique name
800 * @fmt: format string for unique name
801 *
802 * Sets the unique name of a DRM device using the specified format string and
803 * a variable list of arguments. Drivers can use this at driver probe time if
804 * the unique name of the devices they drive is static.
805 *
806 * Return: 0 on success or a negative error code on failure.
807 */
drm_dev_set_unique(struct drm_device * dev,const char * fmt,...)808 int drm_dev_set_unique(struct drm_device *dev, const char *fmt, ...)
809 {
810 va_list ap;
811
812 kfree(dev->unique);
813
814 va_start(ap, fmt);
815 dev->unique = kvasprintf(GFP_KERNEL, fmt, ap);
816 va_end(ap);
817
818 return dev->unique ? 0 : -ENOMEM;
819 }
820 EXPORT_SYMBOL(drm_dev_set_unique);
821
822 /*
823 * DRM Core
824 * The DRM core module initializes all global DRM objects and makes them
825 * available to drivers. Once setup, drivers can probe their respective
826 * devices.
827 * Currently, core management includes:
828 * - The "DRM-Global" key/value database
829 * - Global ID management for connectors
830 * - DRM major number allocation
831 * - DRM minor management
832 * - DRM sysfs class
833 * - DRM debugfs root
834 *
835 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
836 * interface registered on a DRM device, you can request minor numbers from DRM
837 * core. DRM core takes care of major-number management and char-dev
838 * registration. A stub ->open() callback forwards any open() requests to the
839 * registered minor.
840 */
841
drm_stub_open(struct inode * inode,struct file * filp)842 static int drm_stub_open(struct inode *inode, struct file *filp)
843 {
844 const struct file_operations *new_fops;
845 struct drm_minor *minor;
846 int err;
847
848 DRM_DEBUG("\n");
849
850 mutex_lock(&drm_global_mutex);
851 minor = drm_minor_acquire(iminor(inode));
852 if (IS_ERR(minor)) {
853 err = PTR_ERR(minor);
854 goto out_unlock;
855 }
856
857 new_fops = fops_get(minor->dev->driver->fops);
858 if (!new_fops) {
859 err = -ENODEV;
860 goto out_release;
861 }
862
863 replace_fops(filp, new_fops);
864 if (filp->f_op->open)
865 err = filp->f_op->open(inode, filp);
866 else
867 err = 0;
868
869 out_release:
870 drm_minor_release(minor);
871 out_unlock:
872 mutex_unlock(&drm_global_mutex);
873 return err;
874 }
875
876 static const struct file_operations drm_stub_fops = {
877 .owner = THIS_MODULE,
878 .open = drm_stub_open,
879 .llseek = noop_llseek,
880 };
881
drm_core_init(void)882 static int __init drm_core_init(void)
883 {
884 int ret = -ENOMEM;
885
886 drm_global_init();
887 drm_connector_ida_init();
888 idr_init(&drm_minors_idr);
889
890 if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
891 goto err_p1;
892
893 ret = drm_sysfs_init();
894 if (ret < 0) {
895 printk(KERN_ERR "DRM: Error creating drm class.\n");
896 goto err_p2;
897 }
898
899 drm_debugfs_root = debugfs_create_dir("dri", NULL);
900 if (!drm_debugfs_root) {
901 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
902 ret = -1;
903 goto err_p3;
904 }
905
906 DRM_INFO("Initialized %s %d.%d.%d %s\n",
907 CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
908 return 0;
909 err_p3:
910 drm_sysfs_destroy();
911 err_p2:
912 unregister_chrdev(DRM_MAJOR, "drm");
913
914 idr_destroy(&drm_minors_idr);
915 err_p1:
916 return ret;
917 }
918
drm_core_exit(void)919 static void __exit drm_core_exit(void)
920 {
921 debugfs_remove(drm_debugfs_root);
922 drm_sysfs_destroy();
923
924 unregister_chrdev(DRM_MAJOR, "drm");
925
926 drm_connector_ida_destroy();
927 idr_destroy(&drm_minors_idr);
928 }
929
930 module_init(drm_core_init);
931 module_exit(drm_core_exit);
932