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