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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);
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/pseudo_fs.h>
35#include <linux/slab.h>
36#include <linux/srcu.h>
37
38#include <drm/drm_cache.h>
39#include <drm/drm_client.h>
40#include <drm/drm_color_mgmt.h>
41#include <drm/drm_drv.h>
42#include <drm/drm_file.h>
43#include <drm/drm_managed.h>
44#include <drm/drm_mode_object.h>
45#include <drm/drm_print.h>
46
47#include "drm_crtc_internal.h"
48#include "drm_internal.h"
49#include "drm_legacy.h"
50
51MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl");
52MODULE_DESCRIPTION("DRM shared core routines");
53MODULE_LICENSE("GPL and additional rights");
54
55static DEFINE_SPINLOCK(drm_minor_lock);
56static struct idr drm_minors_idr;
57
58/*
59 * If the drm core fails to init for whatever reason,
60 * we should prevent any drivers from registering with it.
61 * It's best to check this at drm_dev_init(), as some drivers
62 * prefer to embed struct drm_device into their own device
63 * structure and call drm_dev_init() themselves.
64 */
65static bool drm_core_init_complete;
66
67static struct dentry *drm_debugfs_root;
68
69DEFINE_STATIC_SRCU(drm_unplug_srcu);
70
71/*
72 * DRM Minors
73 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
74 * of them is represented by a drm_minor object. Depending on the capabilities
75 * of the device-driver, different interfaces are registered.
76 *
77 * Minors can be accessed via dev->$minor_name. This pointer is either
78 * NULL or a valid drm_minor pointer and stays valid as long as the device is
79 * valid. This means, DRM minors have the same life-time as the underlying
80 * device. However, this doesn't mean that the minor is active. Minors are
81 * registered and unregistered dynamically according to device-state.
82 */
83
84static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
85 unsigned int type)
86{
87 switch (type) {
88 case DRM_MINOR_PRIMARY:
89 return &dev->primary;
90 case DRM_MINOR_RENDER:
91 return &dev->render;
92 default:
93 BUG();
94 }
95}
96
97static void drm_minor_alloc_release(struct drm_device *dev, void *data)
98{
99 struct drm_minor *minor = data;
100 unsigned long flags;
101
102 WARN_ON(dev != minor->dev);
103
104 put_device(minor->kdev);
105
106 spin_lock_irqsave(&drm_minor_lock, flags);
107 idr_remove(&drm_minors_idr, minor->index);
108 spin_unlock_irqrestore(&drm_minor_lock, flags);
109}
110
111static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
112{
113 struct drm_minor *minor;
114 unsigned long flags;
115 int r;
116
117 minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL);
118 if (!minor)
119 return -ENOMEM;
120
121 minor->type = type;
122 minor->dev = dev;
123
124 idr_preload(GFP_KERNEL);
125 spin_lock_irqsave(&drm_minor_lock, flags);
126 r = idr_alloc(&drm_minors_idr,
127 NULL,
128 64 * type,
129 64 * (type + 1),
130 GFP_NOWAIT);
131 spin_unlock_irqrestore(&drm_minor_lock, flags);
132 idr_preload_end();
133
134 if (r < 0)
135 return r;
136
137 minor->index = r;
138
139 r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor);
140 if (r)
141 return r;
142
143 minor->kdev = drm_sysfs_minor_alloc(minor);
144 if (IS_ERR(minor->kdev))
145 return PTR_ERR(minor->kdev);
146
147 *drm_minor_get_slot(dev, type) = minor;
148 return 0;
149}
150
151static int drm_minor_register(struct drm_device *dev, unsigned int type)
152{
153 struct drm_minor *minor;
154 unsigned long flags;
155 int ret;
156
157 DRM_DEBUG("\n");
158
159 minor = *drm_minor_get_slot(dev, type);
160 if (!minor)
161 return 0;
162
163 ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root);
164 if (ret) {
165 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
166 goto err_debugfs;
167 }
168
169 ret = device_add(minor->kdev);
170 if (ret)
171 goto err_debugfs;
172
173 /* replace NULL with @minor so lookups will succeed from now on */
174 spin_lock_irqsave(&drm_minor_lock, flags);
175 idr_replace(&drm_minors_idr, minor, minor->index);
176 spin_unlock_irqrestore(&drm_minor_lock, flags);
177
178 DRM_DEBUG("new minor registered %d\n", minor->index);
179 return 0;
180
181err_debugfs:
182 drm_debugfs_cleanup(minor);
183 return ret;
184}
185
186static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
187{
188 struct drm_minor *minor;
189 unsigned long flags;
190
191 minor = *drm_minor_get_slot(dev, type);
192 if (!minor || !device_is_registered(minor->kdev))
193 return;
194
195 /* replace @minor with NULL so lookups will fail from now on */
196 spin_lock_irqsave(&drm_minor_lock, flags);
197 idr_replace(&drm_minors_idr, NULL, minor->index);
198 spin_unlock_irqrestore(&drm_minor_lock, flags);
199
200 device_del(minor->kdev);
201 dev_set_drvdata(minor->kdev, NULL); /* safety belt */
202 drm_debugfs_cleanup(minor);
203}
204
205/*
206 * Looks up the given minor-ID and returns the respective DRM-minor object. The
207 * refence-count of the underlying device is increased so you must release this
208 * object with drm_minor_release().
209 *
210 * As long as you hold this minor, it is guaranteed that the object and the
211 * minor->dev pointer will stay valid! However, the device may get unplugged and
212 * unregistered while you hold the minor.
213 */
214struct drm_minor *drm_minor_acquire(unsigned int minor_id)
215{
216 struct drm_minor *minor;
217 unsigned long flags;
218
219 spin_lock_irqsave(&drm_minor_lock, flags);
220 minor = idr_find(&drm_minors_idr, minor_id);
221 if (minor)
222 drm_dev_get(minor->dev);
223 spin_unlock_irqrestore(&drm_minor_lock, flags);
224
225 if (!minor) {
226 return ERR_PTR(-ENODEV);
227 } else if (drm_dev_is_unplugged(minor->dev)) {
228 drm_dev_put(minor->dev);
229 return ERR_PTR(-ENODEV);
230 }
231
232 return minor;
233}
234
235void drm_minor_release(struct drm_minor *minor)
236{
237 drm_dev_put(minor->dev);
238}
239
240/**
241 * DOC: driver instance overview
242 *
243 * A device instance for a drm driver is represented by &struct drm_device. This
244 * is allocated and initialized with devm_drm_dev_alloc(), usually from
245 * bus-specific ->probe() callbacks implemented by the driver. The driver then
246 * needs to initialize all the various subsystems for the drm device like memory
247 * management, vblank handling, modesetting support and initial output
248 * configuration plus obviously initialize all the corresponding hardware bits.
249 * Finally when everything is up and running and ready for userspace the device
250 * instance can be published using drm_dev_register().
251 *
252 * There is also deprecated support for initalizing device instances using
253 * bus-specific helpers and the &drm_driver.load callback. But due to
254 * backwards-compatibility needs the device instance have to be published too
255 * early, which requires unpretty global locking to make safe and is therefore
256 * only support for existing drivers not yet converted to the new scheme.
257 *
258 * When cleaning up a device instance everything needs to be done in reverse:
259 * First unpublish the device instance with drm_dev_unregister(). Then clean up
260 * any other resources allocated at device initialization and drop the driver's
261 * reference to &drm_device using drm_dev_put().
262 *
263 * Note that any allocation or resource which is visible to userspace must be
264 * released only when the final drm_dev_put() is called, and not when the
265 * driver is unbound from the underlying physical struct &device. Best to use
266 * &drm_device managed resources with drmm_add_action(), drmm_kmalloc() and
267 * related functions.
268 *
269 * devres managed resources like devm_kmalloc() can only be used for resources
270 * directly related to the underlying hardware device, and only used in code
271 * paths fully protected by drm_dev_enter() and drm_dev_exit().
272 *
273 * Display driver example
274 * ~~~~~~~~~~~~~~~~~~~~~~
275 *
276 * The following example shows a typical structure of a DRM display driver.
277 * The example focus on the probe() function and the other functions that is
278 * almost always present and serves as a demonstration of devm_drm_dev_alloc().
279 *
280 * .. code-block:: c
281 *
282 * struct driver_device {
283 * struct drm_device drm;
284 * void *userspace_facing;
285 * struct clk *pclk;
286 * };
287 *
288 * static const struct drm_driver driver_drm_driver = {
289 * [...]
290 * };
291 *
292 * static int driver_probe(struct platform_device *pdev)
293 * {
294 * struct driver_device *priv;
295 * struct drm_device *drm;
296 * int ret;
297 *
298 * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver,
299 * struct driver_device, drm);
300 * if (IS_ERR(priv))
301 * return PTR_ERR(priv);
302 * drm = &priv->drm;
303 *
304 * ret = drmm_mode_config_init(drm);
305 * if (ret)
306 * return ret;
307 *
308 * priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL);
309 * if (!priv->userspace_facing)
310 * return -ENOMEM;
311 *
312 * priv->pclk = devm_clk_get(dev, "PCLK");
313 * if (IS_ERR(priv->pclk))
314 * return PTR_ERR(priv->pclk);
315 *
316 * // Further setup, display pipeline etc
317 *
318 * platform_set_drvdata(pdev, drm);
319 *
320 * drm_mode_config_reset(drm);
321 *
322 * ret = drm_dev_register(drm);
323 * if (ret)
324 * return ret;
325 *
326 * drm_fbdev_generic_setup(drm, 32);
327 *
328 * return 0;
329 * }
330 *
331 * // This function is called before the devm_ resources are released
332 * static int driver_remove(struct platform_device *pdev)
333 * {
334 * struct drm_device *drm = platform_get_drvdata(pdev);
335 *
336 * drm_dev_unregister(drm);
337 * drm_atomic_helper_shutdown(drm)
338 *
339 * return 0;
340 * }
341 *
342 * // This function is called on kernel restart and shutdown
343 * static void driver_shutdown(struct platform_device *pdev)
344 * {
345 * drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
346 * }
347 *
348 * static int __maybe_unused driver_pm_suspend(struct device *dev)
349 * {
350 * return drm_mode_config_helper_suspend(dev_get_drvdata(dev));
351 * }
352 *
353 * static int __maybe_unused driver_pm_resume(struct device *dev)
354 * {
355 * drm_mode_config_helper_resume(dev_get_drvdata(dev));
356 *
357 * return 0;
358 * }
359 *
360 * static const struct dev_pm_ops driver_pm_ops = {
361 * SET_SYSTEM_SLEEP_PM_OPS(driver_pm_suspend, driver_pm_resume)
362 * };
363 *
364 * static struct platform_driver driver_driver = {
365 * .driver = {
366 * [...]
367 * .pm = &driver_pm_ops,
368 * },
369 * .probe = driver_probe,
370 * .remove = driver_remove,
371 * .shutdown = driver_shutdown,
372 * };
373 * module_platform_driver(driver_driver);
374 *
375 * Drivers that want to support device unplugging (USB, DT overlay unload) should
376 * use drm_dev_unplug() instead of drm_dev_unregister(). The driver must protect
377 * regions that is accessing device resources to prevent use after they're
378 * released. This is done using drm_dev_enter() and drm_dev_exit(). There is one
379 * shortcoming however, drm_dev_unplug() marks the drm_device as unplugged before
380 * drm_atomic_helper_shutdown() is called. This means that if the disable code
381 * paths are protected, they will not run on regular driver module unload,
382 * possibily leaving the hardware enabled.
383 */
384
385/**
386 * drm_put_dev - Unregister and release a DRM device
387 * @dev: DRM device
388 *
389 * Called at module unload time or when a PCI device is unplugged.
390 *
391 * Cleans up all DRM device, calling drm_lastclose().
392 *
393 * Note: Use of this function is deprecated. It will eventually go away
394 * completely. Please use drm_dev_unregister() and drm_dev_put() explicitly
395 * instead to make sure that the device isn't userspace accessible any more
396 * while teardown is in progress, ensuring that userspace can't access an
397 * inconsistent state.
398 */
399void drm_put_dev(struct drm_device *dev)
400{
401 DRM_DEBUG("\n");
402
403 if (!dev) {
404 DRM_ERROR("cleanup called no dev\n");
405 return;
406 }
407
408 drm_dev_unregister(dev);
409 drm_dev_put(dev);
410}
411EXPORT_SYMBOL(drm_put_dev);
412
413/**
414 * drm_dev_enter - Enter device critical section
415 * @dev: DRM device
416 * @idx: Pointer to index that will be passed to the matching drm_dev_exit()
417 *
418 * This function marks and protects the beginning of a section that should not
419 * be entered after the device has been unplugged. The section end is marked
420 * with drm_dev_exit(). Calls to this function can be nested.
421 *
422 * Returns:
423 * True if it is OK to enter the section, false otherwise.
424 */
425bool drm_dev_enter(struct drm_device *dev, int *idx)
426{
427 *idx = srcu_read_lock(&drm_unplug_srcu);
428
429 if (dev->unplugged) {
430 srcu_read_unlock(&drm_unplug_srcu, *idx);
431 return false;
432 }
433
434 return true;
435}
436EXPORT_SYMBOL(drm_dev_enter);
437
438/**
439 * drm_dev_exit - Exit device critical section
440 * @idx: index returned from drm_dev_enter()
441 *
442 * This function marks the end of a section that should not be entered after
443 * the device has been unplugged.
444 */
445void drm_dev_exit(int idx)
446{
447 srcu_read_unlock(&drm_unplug_srcu, idx);
448}
449EXPORT_SYMBOL(drm_dev_exit);
450
451/**
452 * drm_dev_unplug - unplug a DRM device
453 * @dev: DRM device
454 *
455 * This unplugs a hotpluggable DRM device, which makes it inaccessible to
456 * userspace operations. Entry-points can use drm_dev_enter() and
457 * drm_dev_exit() to protect device resources in a race free manner. This
458 * essentially unregisters the device like drm_dev_unregister(), but can be
459 * called while there are still open users of @dev.
460 */
461void drm_dev_unplug(struct drm_device *dev)
462{
463 /*
464 * After synchronizing any critical read section is guaranteed to see
465 * the new value of ->unplugged, and any critical section which might
466 * still have seen the old value of ->unplugged is guaranteed to have
467 * finished.
468 */
469 dev->unplugged = true;
470 synchronize_srcu(&drm_unplug_srcu);
471
472 drm_dev_unregister(dev);
473
474 /* Clear all CPU mappings pointing to this device */
475 unmap_mapping_range(dev->anon_inode->i_mapping, 0, 0, 1);
476}
477EXPORT_SYMBOL(drm_dev_unplug);
478
479/*
480 * DRM internal mount
481 * We want to be able to allocate our own "struct address_space" to control
482 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
483 * stand-alone address_space objects, so we need an underlying inode. As there
484 * is no way to allocate an independent inode easily, we need a fake internal
485 * VFS mount-point.
486 *
487 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
488 * frees it again. You are allowed to use iget() and iput() to get references to
489 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
490 * drm_fs_inode_free() call (which does not have to be the last iput()).
491 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
492 * between multiple inode-users. You could, technically, call
493 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
494 * iput(), but this way you'd end up with a new vfsmount for each inode.
495 */
496
497static int drm_fs_cnt;
498static struct vfsmount *drm_fs_mnt;
499
500static int drm_fs_init_fs_context(struct fs_context *fc)
501{
502 return init_pseudo(fc, 0x010203ff) ? 0 : -ENOMEM;
503}
504
505static struct file_system_type drm_fs_type = {
506 .name = "drm",
507 .owner = THIS_MODULE,
508 .init_fs_context = drm_fs_init_fs_context,
509 .kill_sb = kill_anon_super,
510};
511
512static struct inode *drm_fs_inode_new(void)
513{
514 struct inode *inode;
515 int r;
516
517 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
518 if (r < 0) {
519 DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
520 return ERR_PTR(r);
521 }
522
523 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
524 if (IS_ERR(inode))
525 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
526
527 return inode;
528}
529
530static void drm_fs_inode_free(struct inode *inode)
531{
532 if (inode) {
533 iput(inode);
534 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
535 }
536}
537
538/**
539 * DOC: component helper usage recommendations
540 *
541 * DRM drivers that drive hardware where a logical device consists of a pile of
542 * independent hardware blocks are recommended to use the :ref:`component helper
543 * library<component>`. For consistency and better options for code reuse the
544 * following guidelines apply:
545 *
546 * - The entire device initialization procedure should be run from the
547 * &component_master_ops.master_bind callback, starting with
548 * devm_drm_dev_alloc(), then binding all components with
549 * component_bind_all() and finishing with drm_dev_register().
550 *
551 * - The opaque pointer passed to all components through component_bind_all()
552 * should point at &struct drm_device of the device instance, not some driver
553 * specific private structure.
554 *
555 * - The component helper fills the niche where further standardization of
556 * interfaces is not practical. When there already is, or will be, a
557 * standardized interface like &drm_bridge or &drm_panel, providing its own
558 * functions to find such components at driver load time, like
559 * drm_of_find_panel_or_bridge(), then the component helper should not be
560 * used.
561 */
562
563static void drm_dev_init_release(struct drm_device *dev, void *res)
564{
565 drm_legacy_ctxbitmap_cleanup(dev);
566 drm_legacy_remove_map_hash(dev);
567 drm_fs_inode_free(dev->anon_inode);
568
569 put_device(dev->dev);
570 /* Prevent use-after-free in drm_managed_release when debugging is
571 * enabled. Slightly awkward, but can't really be helped. */
572 dev->dev = NULL;
573 mutex_destroy(&dev->master_mutex);
574 mutex_destroy(&dev->clientlist_mutex);
575 mutex_destroy(&dev->filelist_mutex);
576 mutex_destroy(&dev->struct_mutex);
577 drm_legacy_destroy_members(dev);
578}
579
580static int drm_dev_init(struct drm_device *dev,
581 const struct drm_driver *driver,
582 struct device *parent)
583{
584 int ret;
585
586 if (!drm_core_init_complete) {
587 DRM_ERROR("DRM core is not initialized\n");
588 return -ENODEV;
589 }
590
591 if (WARN_ON(!parent))
592 return -EINVAL;
593
594 kref_init(&dev->ref);
595 dev->dev = get_device(parent);
596 dev->driver = driver;
597
598 INIT_LIST_HEAD(&dev->managed.resources);
599 spin_lock_init(&dev->managed.lock);
600
601 /* no per-device feature limits by default */
602 dev->driver_features = ~0u;
603
604 drm_legacy_init_members(dev);
605 INIT_LIST_HEAD(&dev->filelist);
606 INIT_LIST_HEAD(&dev->filelist_internal);
607 INIT_LIST_HEAD(&dev->clientlist);
608 INIT_LIST_HEAD(&dev->vblank_event_list);
609
610 spin_lock_init(&dev->event_lock);
611 mutex_init(&dev->struct_mutex);
612 mutex_init(&dev->filelist_mutex);
613 mutex_init(&dev->clientlist_mutex);
614 mutex_init(&dev->master_mutex);
615
616 ret = drmm_add_action(dev, drm_dev_init_release, NULL);
617 if (ret)
618 return ret;
619
620 dev->anon_inode = drm_fs_inode_new();
621 if (IS_ERR(dev->anon_inode)) {
622 ret = PTR_ERR(dev->anon_inode);
623 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
624 goto err;
625 }
626
627 if (drm_core_check_feature(dev, DRIVER_RENDER)) {
628 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
629 if (ret)
630 goto err;
631 }
632
633 ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY);
634 if (ret)
635 goto err;
636
637 ret = drm_legacy_create_map_hash(dev);
638 if (ret)
639 goto err;
640
641 drm_legacy_ctxbitmap_init(dev);
642
643 if (drm_core_check_feature(dev, DRIVER_GEM)) {
644 ret = drm_gem_init(dev);
645 if (ret) {
646 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
647 goto err;
648 }
649 }
650
651 ret = drm_dev_set_unique(dev, dev_name(parent));
652 if (ret)
653 goto err;
654
655 return 0;
656
657err:
658 drm_managed_release(dev);
659
660 return ret;
661}
662
663static void devm_drm_dev_init_release(void *data)
664{
665 drm_dev_put(data);
666}
667
668static int devm_drm_dev_init(struct device *parent,
669 struct drm_device *dev,
670 const struct drm_driver *driver)
671{
672 int ret;
673
674 ret = drm_dev_init(dev, driver, parent);
675 if (ret)
676 return ret;
677
678 return devm_add_action_or_reset(parent,
679 devm_drm_dev_init_release, dev);
680}
681
682void *__devm_drm_dev_alloc(struct device *parent,
683 const struct drm_driver *driver,
684 size_t size, size_t offset)
685{
686 void *container;
687 struct drm_device *drm;
688 int ret;
689
690 container = kzalloc(size, GFP_KERNEL);
691 if (!container)
692 return ERR_PTR(-ENOMEM);
693
694 drm = container + offset;
695 ret = devm_drm_dev_init(parent, drm, driver);
696 if (ret) {
697 kfree(container);
698 return ERR_PTR(ret);
699 }
700 drmm_add_final_kfree(drm, container);
701
702 return container;
703}
704EXPORT_SYMBOL(__devm_drm_dev_alloc);
705
706/**
707 * drm_dev_alloc - Allocate new DRM device
708 * @driver: DRM driver to allocate device for
709 * @parent: Parent device object
710 *
711 * This is the deprecated version of devm_drm_dev_alloc(), which does not support
712 * subclassing through embedding the struct &drm_device in a driver private
713 * structure, and which does not support automatic cleanup through devres.
714 *
715 * RETURNS:
716 * Pointer to new DRM device, or ERR_PTR on failure.
717 */
718struct drm_device *drm_dev_alloc(const struct drm_driver *driver,
719 struct device *parent)
720{
721 struct drm_device *dev;
722 int ret;
723
724 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
725 if (!dev)
726 return ERR_PTR(-ENOMEM);
727
728 ret = drm_dev_init(dev, driver, parent);
729 if (ret) {
730 kfree(dev);
731 return ERR_PTR(ret);
732 }
733
734 drmm_add_final_kfree(dev, dev);
735
736 return dev;
737}
738EXPORT_SYMBOL(drm_dev_alloc);
739
740static void drm_dev_release(struct kref *ref)
741{
742 struct drm_device *dev = container_of(ref, struct drm_device, ref);
743
744 if (dev->driver->release)
745 dev->driver->release(dev);
746
747 drm_managed_release(dev);
748
749 kfree(dev->managed.final_kfree);
750}
751
752/**
753 * drm_dev_get - Take reference of a DRM device
754 * @dev: device to take reference of or NULL
755 *
756 * This increases the ref-count of @dev by one. You *must* already own a
757 * reference when calling this. Use drm_dev_put() to drop this reference
758 * again.
759 *
760 * This function never fails. However, this function does not provide *any*
761 * guarantee whether the device is alive or running. It only provides a
762 * reference to the object and the memory associated with it.
763 */
764void drm_dev_get(struct drm_device *dev)
765{
766 if (dev)
767 kref_get(&dev->ref);
768}
769EXPORT_SYMBOL(drm_dev_get);
770
771/**
772 * drm_dev_put - Drop reference of a DRM device
773 * @dev: device to drop reference of or NULL
774 *
775 * This decreases the ref-count of @dev by one. The device is destroyed if the
776 * ref-count drops to zero.
777 */
778void drm_dev_put(struct drm_device *dev)
779{
780 if (dev)
781 kref_put(&dev->ref, drm_dev_release);
782}
783EXPORT_SYMBOL(drm_dev_put);
784
785static int create_compat_control_link(struct drm_device *dev)
786{
787 struct drm_minor *minor;
788 char *name;
789 int ret;
790
791 if (!drm_core_check_feature(dev, DRIVER_MODESET))
792 return 0;
793
794 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
795 if (!minor)
796 return 0;
797
798 /*
799 * Some existing userspace out there uses the existing of the controlD*
800 * sysfs files to figure out whether it's a modeset driver. It only does
801 * readdir, hence a symlink is sufficient (and the least confusing
802 * option). Otherwise controlD* is entirely unused.
803 *
804 * Old controlD chardev have been allocated in the range
805 * 64-127.
806 */
807 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
808 if (!name)
809 return -ENOMEM;
810
811 ret = sysfs_create_link(minor->kdev->kobj.parent,
812 &minor->kdev->kobj,
813 name);
814
815 kfree(name);
816
817 return ret;
818}
819
820static void remove_compat_control_link(struct drm_device *dev)
821{
822 struct drm_minor *minor;
823 char *name;
824
825 if (!drm_core_check_feature(dev, DRIVER_MODESET))
826 return;
827
828 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
829 if (!minor)
830 return;
831
832 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
833 if (!name)
834 return;
835
836 sysfs_remove_link(minor->kdev->kobj.parent, name);
837
838 kfree(name);
839}
840
841/**
842 * drm_dev_register - Register DRM device
843 * @dev: Device to register
844 * @flags: Flags passed to the driver's .load() function
845 *
846 * Register the DRM device @dev with the system, advertise device to user-space
847 * and start normal device operation. @dev must be initialized via drm_dev_init()
848 * previously.
849 *
850 * Never call this twice on any device!
851 *
852 * NOTE: To ensure backward compatibility with existing drivers method this
853 * function calls the &drm_driver.load method after registering the device
854 * nodes, creating race conditions. Usage of the &drm_driver.load methods is
855 * therefore deprecated, drivers must perform all initialization before calling
856 * drm_dev_register().
857 *
858 * RETURNS:
859 * 0 on success, negative error code on failure.
860 */
861int drm_dev_register(struct drm_device *dev, unsigned long flags)
862{
863 const struct drm_driver *driver = dev->driver;
864 int ret;
865
866 if (!driver->load)
867 drm_mode_config_validate(dev);
868
869 WARN_ON(!dev->managed.final_kfree);
870
871 if (drm_dev_needs_global_mutex(dev))
872 mutex_lock(&drm_global_mutex);
873
874 ret = drm_minor_register(dev, DRM_MINOR_RENDER);
875 if (ret)
876 goto err_minors;
877
878 ret = drm_minor_register(dev, DRM_MINOR_PRIMARY);
879 if (ret)
880 goto err_minors;
881
882 ret = create_compat_control_link(dev);
883 if (ret)
884 goto err_minors;
885
886 dev->registered = true;
887
888 if (dev->driver->load) {
889 ret = dev->driver->load(dev, flags);
890 if (ret)
891 goto err_minors;
892 }
893
894 if (drm_core_check_feature(dev, DRIVER_MODESET))
895 drm_modeset_register_all(dev);
896
897 DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
898 driver->name, driver->major, driver->minor,
899 driver->patchlevel, driver->date,
900 dev->dev ? dev_name(dev->dev) : "virtual device",
901 dev->primary->index);
902
903 goto out_unlock;
904
905err_minors:
906 remove_compat_control_link(dev);
907 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
908 drm_minor_unregister(dev, DRM_MINOR_RENDER);
909out_unlock:
910 if (drm_dev_needs_global_mutex(dev))
911 mutex_unlock(&drm_global_mutex);
912 return ret;
913}
914EXPORT_SYMBOL(drm_dev_register);
915
916/**
917 * drm_dev_unregister - Unregister DRM device
918 * @dev: Device to unregister
919 *
920 * Unregister the DRM device from the system. This does the reverse of
921 * drm_dev_register() but does not deallocate the device. The caller must call
922 * drm_dev_put() to drop their final reference.
923 *
924 * A special form of unregistering for hotpluggable devices is drm_dev_unplug(),
925 * which can be called while there are still open users of @dev.
926 *
927 * This should be called first in the device teardown code to make sure
928 * userspace can't access the device instance any more.
929 */
930void drm_dev_unregister(struct drm_device *dev)
931{
932 if (drm_core_check_feature(dev, DRIVER_LEGACY))
933 drm_lastclose(dev);
934
935 dev->registered = false;
936
937 drm_client_dev_unregister(dev);
938
939 if (drm_core_check_feature(dev, DRIVER_MODESET))
940 drm_modeset_unregister_all(dev);
941
942 if (dev->driver->unload)
943 dev->driver->unload(dev);
944
945 drm_legacy_pci_agp_destroy(dev);
946 drm_legacy_rmmaps(dev);
947
948 remove_compat_control_link(dev);
949 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
950 drm_minor_unregister(dev, DRM_MINOR_RENDER);
951}
952EXPORT_SYMBOL(drm_dev_unregister);
953
954/**
955 * drm_dev_set_unique - Set the unique name of a DRM device
956 * @dev: device of which to set the unique name
957 * @name: unique name
958 *
959 * Sets the unique name of a DRM device using the specified string. This is
960 * already done by drm_dev_init(), drivers should only override the default
961 * unique name for backwards compatibility reasons.
962 *
963 * Return: 0 on success or a negative error code on failure.
964 */
965int drm_dev_set_unique(struct drm_device *dev, const char *name)
966{
967 drmm_kfree(dev, dev->unique);
968 dev->unique = drmm_kstrdup(dev, name, GFP_KERNEL);
969
970 return dev->unique ? 0 : -ENOMEM;
971}
972EXPORT_SYMBOL(drm_dev_set_unique);
973
974/*
975 * DRM Core
976 * The DRM core module initializes all global DRM objects and makes them
977 * available to drivers. Once setup, drivers can probe their respective
978 * devices.
979 * Currently, core management includes:
980 * - The "DRM-Global" key/value database
981 * - Global ID management for connectors
982 * - DRM major number allocation
983 * - DRM minor management
984 * - DRM sysfs class
985 * - DRM debugfs root
986 *
987 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
988 * interface registered on a DRM device, you can request minor numbers from DRM
989 * core. DRM core takes care of major-number management and char-dev
990 * registration. A stub ->open() callback forwards any open() requests to the
991 * registered minor.
992 */
993
994static int drm_stub_open(struct inode *inode, struct file *filp)
995{
996 const struct file_operations *new_fops;
997 struct drm_minor *minor;
998 int err;
999
1000 DRM_DEBUG("\n");
1001
1002 minor = drm_minor_acquire(iminor(inode));
1003 if (IS_ERR(minor))
1004 return PTR_ERR(minor);
1005
1006 new_fops = fops_get(minor->dev->driver->fops);
1007 if (!new_fops) {
1008 err = -ENODEV;
1009 goto out;
1010 }
1011
1012 replace_fops(filp, new_fops);
1013 if (filp->f_op->open)
1014 err = filp->f_op->open(inode, filp);
1015 else
1016 err = 0;
1017
1018out:
1019 drm_minor_release(minor);
1020
1021 return err;
1022}
1023
1024static const struct file_operations drm_stub_fops = {
1025 .owner = THIS_MODULE,
1026 .open = drm_stub_open,
1027 .llseek = noop_llseek,
1028};
1029
1030static void drm_core_exit(void)
1031{
1032 unregister_chrdev(DRM_MAJOR, "drm");
1033 debugfs_remove(drm_debugfs_root);
1034 drm_sysfs_destroy();
1035 idr_destroy(&drm_minors_idr);
1036 drm_connector_ida_destroy();
1037}
1038
1039static int __init drm_core_init(void)
1040{
1041 int ret;
1042
1043 drm_connector_ida_init();
1044 idr_init(&drm_minors_idr);
1045 drm_memcpy_init_early();
1046
1047 ret = drm_sysfs_init();
1048 if (ret < 0) {
1049 DRM_ERROR("Cannot create DRM class: %d\n", ret);
1050 goto error;
1051 }
1052
1053 drm_debugfs_root = debugfs_create_dir("dri", NULL);
1054
1055 ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops);
1056 if (ret < 0)
1057 goto error;
1058
1059 drm_core_init_complete = true;
1060
1061 DRM_DEBUG("Initialized\n");
1062 return 0;
1063
1064error:
1065 drm_core_exit();
1066 return ret;
1067}
1068
1069module_init(drm_core_init);
1070module_exit(drm_core_exit);