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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/pseudo_fs.h>
35#include <linux/slab.h>
36#include <linux/srcu.h>
37
38#include <drm/drm_accel.h>
39#include <drm/drm_cache.h>
40#include <drm/drm_client.h>
41#include <drm/drm_color_mgmt.h>
42#include <drm/drm_drv.h>
43#include <drm/drm_file.h>
44#include <drm/drm_managed.h>
45#include <drm/drm_mode_object.h>
46#include <drm/drm_print.h>
47#include <drm/drm_privacy_screen_machine.h>
48
49#include "drm_crtc_internal.h"
50#include "drm_internal.h"
51
52MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl");
53MODULE_DESCRIPTION("DRM shared core routines");
54MODULE_LICENSE("GPL and additional rights");
55
56static DEFINE_SPINLOCK(drm_minor_lock);
57static struct idr drm_minors_idr;
58
59/*
60 * If the drm core fails to init for whatever reason,
61 * we should prevent any drivers from registering with it.
62 * It's best to check this at drm_dev_init(), as some drivers
63 * prefer to embed struct drm_device into their own device
64 * structure and call drm_dev_init() themselves.
65 */
66static bool drm_core_init_complete;
67
68static struct dentry *drm_debugfs_root;
69
70DEFINE_STATIC_SRCU(drm_unplug_srcu);
71
72/*
73 * DRM Minors
74 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
75 * of them is represented by a drm_minor object. Depending on the capabilities
76 * of the device-driver, different interfaces are registered.
77 *
78 * Minors can be accessed via dev->$minor_name. This pointer is either
79 * NULL or a valid drm_minor pointer and stays valid as long as the device is
80 * valid. This means, DRM minors have the same life-time as the underlying
81 * device. However, this doesn't mean that the minor is active. Minors are
82 * registered and unregistered dynamically according to device-state.
83 */
84
85static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
86 enum drm_minor_type type)
87{
88 switch (type) {
89 case DRM_MINOR_PRIMARY:
90 return &dev->primary;
91 case DRM_MINOR_RENDER:
92 return &dev->render;
93 case DRM_MINOR_ACCEL:
94 return &dev->accel;
95 default:
96 BUG();
97 }
98}
99
100static void drm_minor_alloc_release(struct drm_device *dev, void *data)
101{
102 struct drm_minor *minor = data;
103 unsigned long flags;
104
105 WARN_ON(dev != minor->dev);
106
107 put_device(minor->kdev);
108
109 if (minor->type == DRM_MINOR_ACCEL) {
110 accel_minor_remove(minor->index);
111 } else {
112 spin_lock_irqsave(&drm_minor_lock, flags);
113 idr_remove(&drm_minors_idr, minor->index);
114 spin_unlock_irqrestore(&drm_minor_lock, flags);
115 }
116}
117
118static int drm_minor_alloc(struct drm_device *dev, enum drm_minor_type type)
119{
120 struct drm_minor *minor;
121 unsigned long flags;
122 int r;
123
124 minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL);
125 if (!minor)
126 return -ENOMEM;
127
128 minor->type = type;
129 minor->dev = dev;
130
131 idr_preload(GFP_KERNEL);
132 if (type == DRM_MINOR_ACCEL) {
133 r = accel_minor_alloc();
134 } else {
135 spin_lock_irqsave(&drm_minor_lock, flags);
136 r = idr_alloc(&drm_minors_idr,
137 NULL,
138 64 * type,
139 64 * (type + 1),
140 GFP_NOWAIT);
141 spin_unlock_irqrestore(&drm_minor_lock, flags);
142 }
143 idr_preload_end();
144
145 if (r < 0)
146 return r;
147
148 minor->index = r;
149
150 r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor);
151 if (r)
152 return r;
153
154 minor->kdev = drm_sysfs_minor_alloc(minor);
155 if (IS_ERR(minor->kdev))
156 return PTR_ERR(minor->kdev);
157
158 *drm_minor_get_slot(dev, type) = minor;
159 return 0;
160}
161
162static int drm_minor_register(struct drm_device *dev, enum drm_minor_type type)
163{
164 struct drm_minor *minor;
165 unsigned long flags;
166 int ret;
167
168 DRM_DEBUG("\n");
169
170 minor = *drm_minor_get_slot(dev, type);
171 if (!minor)
172 return 0;
173
174 if (minor->type != DRM_MINOR_ACCEL) {
175 ret = drm_debugfs_register(minor, minor->index,
176 drm_debugfs_root);
177 if (ret) {
178 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
179 goto err_debugfs;
180 }
181 }
182
183 ret = device_add(minor->kdev);
184 if (ret)
185 goto err_debugfs;
186
187 /* replace NULL with @minor so lookups will succeed from now on */
188 if (minor->type == DRM_MINOR_ACCEL) {
189 accel_minor_replace(minor, minor->index);
190 } else {
191 spin_lock_irqsave(&drm_minor_lock, flags);
192 idr_replace(&drm_minors_idr, minor, minor->index);
193 spin_unlock_irqrestore(&drm_minor_lock, flags);
194 }
195
196 DRM_DEBUG("new minor registered %d\n", minor->index);
197 return 0;
198
199err_debugfs:
200 drm_debugfs_unregister(minor);
201 return ret;
202}
203
204static void drm_minor_unregister(struct drm_device *dev, enum drm_minor_type type)
205{
206 struct drm_minor *minor;
207 unsigned long flags;
208
209 minor = *drm_minor_get_slot(dev, type);
210 if (!minor || !device_is_registered(minor->kdev))
211 return;
212
213 /* replace @minor with NULL so lookups will fail from now on */
214 if (minor->type == DRM_MINOR_ACCEL) {
215 accel_minor_replace(NULL, minor->index);
216 } else {
217 spin_lock_irqsave(&drm_minor_lock, flags);
218 idr_replace(&drm_minors_idr, NULL, minor->index);
219 spin_unlock_irqrestore(&drm_minor_lock, flags);
220 }
221
222 device_del(minor->kdev);
223 dev_set_drvdata(minor->kdev, NULL); /* safety belt */
224 drm_debugfs_unregister(minor);
225}
226
227/*
228 * Looks up the given minor-ID and returns the respective DRM-minor object. The
229 * refence-count of the underlying device is increased so you must release this
230 * object with drm_minor_release().
231 *
232 * As long as you hold this minor, it is guaranteed that the object and the
233 * minor->dev pointer will stay valid! However, the device may get unplugged and
234 * unregistered while you hold the minor.
235 */
236struct drm_minor *drm_minor_acquire(unsigned int minor_id)
237{
238 struct drm_minor *minor;
239 unsigned long flags;
240
241 spin_lock_irqsave(&drm_minor_lock, flags);
242 minor = idr_find(&drm_minors_idr, minor_id);
243 if (minor)
244 drm_dev_get(minor->dev);
245 spin_unlock_irqrestore(&drm_minor_lock, flags);
246
247 if (!minor) {
248 return ERR_PTR(-ENODEV);
249 } else if (drm_dev_is_unplugged(minor->dev)) {
250 drm_dev_put(minor->dev);
251 return ERR_PTR(-ENODEV);
252 }
253
254 return minor;
255}
256
257void drm_minor_release(struct drm_minor *minor)
258{
259 drm_dev_put(minor->dev);
260}
261
262/**
263 * DOC: driver instance overview
264 *
265 * A device instance for a drm driver is represented by &struct drm_device. This
266 * is allocated and initialized with devm_drm_dev_alloc(), usually from
267 * bus-specific ->probe() callbacks implemented by the driver. The driver then
268 * needs to initialize all the various subsystems for the drm device like memory
269 * management, vblank handling, modesetting support and initial output
270 * configuration plus obviously initialize all the corresponding hardware bits.
271 * Finally when everything is up and running and ready for userspace the device
272 * instance can be published using drm_dev_register().
273 *
274 * There is also deprecated support for initializing device instances using
275 * bus-specific helpers and the &drm_driver.load callback. But due to
276 * backwards-compatibility needs the device instance have to be published too
277 * early, which requires unpretty global locking to make safe and is therefore
278 * only support for existing drivers not yet converted to the new scheme.
279 *
280 * When cleaning up a device instance everything needs to be done in reverse:
281 * First unpublish the device instance with drm_dev_unregister(). Then clean up
282 * any other resources allocated at device initialization and drop the driver's
283 * reference to &drm_device using drm_dev_put().
284 *
285 * Note that any allocation or resource which is visible to userspace must be
286 * released only when the final drm_dev_put() is called, and not when the
287 * driver is unbound from the underlying physical struct &device. Best to use
288 * &drm_device managed resources with drmm_add_action(), drmm_kmalloc() and
289 * related functions.
290 *
291 * devres managed resources like devm_kmalloc() can only be used for resources
292 * directly related to the underlying hardware device, and only used in code
293 * paths fully protected by drm_dev_enter() and drm_dev_exit().
294 *
295 * Display driver example
296 * ~~~~~~~~~~~~~~~~~~~~~~
297 *
298 * The following example shows a typical structure of a DRM display driver.
299 * The example focus on the probe() function and the other functions that is
300 * almost always present and serves as a demonstration of devm_drm_dev_alloc().
301 *
302 * .. code-block:: c
303 *
304 * struct driver_device {
305 * struct drm_device drm;
306 * void *userspace_facing;
307 * struct clk *pclk;
308 * };
309 *
310 * static const struct drm_driver driver_drm_driver = {
311 * [...]
312 * };
313 *
314 * static int driver_probe(struct platform_device *pdev)
315 * {
316 * struct driver_device *priv;
317 * struct drm_device *drm;
318 * int ret;
319 *
320 * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver,
321 * struct driver_device, drm);
322 * if (IS_ERR(priv))
323 * return PTR_ERR(priv);
324 * drm = &priv->drm;
325 *
326 * ret = drmm_mode_config_init(drm);
327 * if (ret)
328 * return ret;
329 *
330 * priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL);
331 * if (!priv->userspace_facing)
332 * return -ENOMEM;
333 *
334 * priv->pclk = devm_clk_get(dev, "PCLK");
335 * if (IS_ERR(priv->pclk))
336 * return PTR_ERR(priv->pclk);
337 *
338 * // Further setup, display pipeline etc
339 *
340 * platform_set_drvdata(pdev, drm);
341 *
342 * drm_mode_config_reset(drm);
343 *
344 * ret = drm_dev_register(drm);
345 * if (ret)
346 * return ret;
347 *
348 * drm_fbdev_generic_setup(drm, 32);
349 *
350 * return 0;
351 * }
352 *
353 * // This function is called before the devm_ resources are released
354 * static int driver_remove(struct platform_device *pdev)
355 * {
356 * struct drm_device *drm = platform_get_drvdata(pdev);
357 *
358 * drm_dev_unregister(drm);
359 * drm_atomic_helper_shutdown(drm)
360 *
361 * return 0;
362 * }
363 *
364 * // This function is called on kernel restart and shutdown
365 * static void driver_shutdown(struct platform_device *pdev)
366 * {
367 * drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
368 * }
369 *
370 * static int __maybe_unused driver_pm_suspend(struct device *dev)
371 * {
372 * return drm_mode_config_helper_suspend(dev_get_drvdata(dev));
373 * }
374 *
375 * static int __maybe_unused driver_pm_resume(struct device *dev)
376 * {
377 * drm_mode_config_helper_resume(dev_get_drvdata(dev));
378 *
379 * return 0;
380 * }
381 *
382 * static const struct dev_pm_ops driver_pm_ops = {
383 * SET_SYSTEM_SLEEP_PM_OPS(driver_pm_suspend, driver_pm_resume)
384 * };
385 *
386 * static struct platform_driver driver_driver = {
387 * .driver = {
388 * [...]
389 * .pm = &driver_pm_ops,
390 * },
391 * .probe = driver_probe,
392 * .remove = driver_remove,
393 * .shutdown = driver_shutdown,
394 * };
395 * module_platform_driver(driver_driver);
396 *
397 * Drivers that want to support device unplugging (USB, DT overlay unload) should
398 * use drm_dev_unplug() instead of drm_dev_unregister(). The driver must protect
399 * regions that is accessing device resources to prevent use after they're
400 * released. This is done using drm_dev_enter() and drm_dev_exit(). There is one
401 * shortcoming however, drm_dev_unplug() marks the drm_device as unplugged before
402 * drm_atomic_helper_shutdown() is called. This means that if the disable code
403 * paths are protected, they will not run on regular driver module unload,
404 * possibly leaving the hardware enabled.
405 */
406
407/**
408 * drm_put_dev - Unregister and release a DRM device
409 * @dev: DRM device
410 *
411 * Called at module unload time or when a PCI device is unplugged.
412 *
413 * Cleans up all DRM device, calling drm_lastclose().
414 *
415 * Note: Use of this function is deprecated. It will eventually go away
416 * completely. Please use drm_dev_unregister() and drm_dev_put() explicitly
417 * instead to make sure that the device isn't userspace accessible any more
418 * while teardown is in progress, ensuring that userspace can't access an
419 * inconsistent state.
420 */
421void drm_put_dev(struct drm_device *dev)
422{
423 DRM_DEBUG("\n");
424
425 if (!dev) {
426 DRM_ERROR("cleanup called no dev\n");
427 return;
428 }
429
430 drm_dev_unregister(dev);
431 drm_dev_put(dev);
432}
433EXPORT_SYMBOL(drm_put_dev);
434
435/**
436 * drm_dev_enter - Enter device critical section
437 * @dev: DRM device
438 * @idx: Pointer to index that will be passed to the matching drm_dev_exit()
439 *
440 * This function marks and protects the beginning of a section that should not
441 * be entered after the device has been unplugged. The section end is marked
442 * with drm_dev_exit(). Calls to this function can be nested.
443 *
444 * Returns:
445 * True if it is OK to enter the section, false otherwise.
446 */
447bool drm_dev_enter(struct drm_device *dev, int *idx)
448{
449 *idx = srcu_read_lock(&drm_unplug_srcu);
450
451 if (dev->unplugged) {
452 srcu_read_unlock(&drm_unplug_srcu, *idx);
453 return false;
454 }
455
456 return true;
457}
458EXPORT_SYMBOL(drm_dev_enter);
459
460/**
461 * drm_dev_exit - Exit device critical section
462 * @idx: index returned from drm_dev_enter()
463 *
464 * This function marks the end of a section that should not be entered after
465 * the device has been unplugged.
466 */
467void drm_dev_exit(int idx)
468{
469 srcu_read_unlock(&drm_unplug_srcu, idx);
470}
471EXPORT_SYMBOL(drm_dev_exit);
472
473/**
474 * drm_dev_unplug - unplug a DRM device
475 * @dev: DRM device
476 *
477 * This unplugs a hotpluggable DRM device, which makes it inaccessible to
478 * userspace operations. Entry-points can use drm_dev_enter() and
479 * drm_dev_exit() to protect device resources in a race free manner. This
480 * essentially unregisters the device like drm_dev_unregister(), but can be
481 * called while there are still open users of @dev.
482 */
483void drm_dev_unplug(struct drm_device *dev)
484{
485 /*
486 * After synchronizing any critical read section is guaranteed to see
487 * the new value of ->unplugged, and any critical section which might
488 * still have seen the old value of ->unplugged is guaranteed to have
489 * finished.
490 */
491 dev->unplugged = true;
492 synchronize_srcu(&drm_unplug_srcu);
493
494 drm_dev_unregister(dev);
495
496 /* Clear all CPU mappings pointing to this device */
497 unmap_mapping_range(dev->anon_inode->i_mapping, 0, 0, 1);
498}
499EXPORT_SYMBOL(drm_dev_unplug);
500
501/*
502 * DRM internal mount
503 * We want to be able to allocate our own "struct address_space" to control
504 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
505 * stand-alone address_space objects, so we need an underlying inode. As there
506 * is no way to allocate an independent inode easily, we need a fake internal
507 * VFS mount-point.
508 *
509 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
510 * frees it again. You are allowed to use iget() and iput() to get references to
511 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
512 * drm_fs_inode_free() call (which does not have to be the last iput()).
513 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
514 * between multiple inode-users. You could, technically, call
515 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
516 * iput(), but this way you'd end up with a new vfsmount for each inode.
517 */
518
519static int drm_fs_cnt;
520static struct vfsmount *drm_fs_mnt;
521
522static int drm_fs_init_fs_context(struct fs_context *fc)
523{
524 return init_pseudo(fc, 0x010203ff) ? 0 : -ENOMEM;
525}
526
527static struct file_system_type drm_fs_type = {
528 .name = "drm",
529 .owner = THIS_MODULE,
530 .init_fs_context = drm_fs_init_fs_context,
531 .kill_sb = kill_anon_super,
532};
533
534static struct inode *drm_fs_inode_new(void)
535{
536 struct inode *inode;
537 int r;
538
539 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
540 if (r < 0) {
541 DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
542 return ERR_PTR(r);
543 }
544
545 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
546 if (IS_ERR(inode))
547 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
548
549 return inode;
550}
551
552static void drm_fs_inode_free(struct inode *inode)
553{
554 if (inode) {
555 iput(inode);
556 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
557 }
558}
559
560/**
561 * DOC: component helper usage recommendations
562 *
563 * DRM drivers that drive hardware where a logical device consists of a pile of
564 * independent hardware blocks are recommended to use the :ref:`component helper
565 * library<component>`. For consistency and better options for code reuse the
566 * following guidelines apply:
567 *
568 * - The entire device initialization procedure should be run from the
569 * &component_master_ops.master_bind callback, starting with
570 * devm_drm_dev_alloc(), then binding all components with
571 * component_bind_all() and finishing with drm_dev_register().
572 *
573 * - The opaque pointer passed to all components through component_bind_all()
574 * should point at &struct drm_device of the device instance, not some driver
575 * specific private structure.
576 *
577 * - The component helper fills the niche where further standardization of
578 * interfaces is not practical. When there already is, or will be, a
579 * standardized interface like &drm_bridge or &drm_panel, providing its own
580 * functions to find such components at driver load time, like
581 * drm_of_find_panel_or_bridge(), then the component helper should not be
582 * used.
583 */
584
585static void drm_dev_init_release(struct drm_device *dev, void *res)
586{
587 drm_fs_inode_free(dev->anon_inode);
588
589 put_device(dev->dev);
590 /* Prevent use-after-free in drm_managed_release when debugging is
591 * enabled. Slightly awkward, but can't really be helped. */
592 dev->dev = NULL;
593 mutex_destroy(&dev->master_mutex);
594 mutex_destroy(&dev->clientlist_mutex);
595 mutex_destroy(&dev->filelist_mutex);
596 mutex_destroy(&dev->struct_mutex);
597}
598
599static int drm_dev_init(struct drm_device *dev,
600 const struct drm_driver *driver,
601 struct device *parent)
602{
603 struct inode *inode;
604 int ret;
605
606 if (!drm_core_init_complete) {
607 DRM_ERROR("DRM core is not initialized\n");
608 return -ENODEV;
609 }
610
611 if (WARN_ON(!parent))
612 return -EINVAL;
613
614 kref_init(&dev->ref);
615 dev->dev = get_device(parent);
616 dev->driver = driver;
617
618 INIT_LIST_HEAD(&dev->managed.resources);
619 spin_lock_init(&dev->managed.lock);
620
621 /* no per-device feature limits by default */
622 dev->driver_features = ~0u;
623
624 if (drm_core_check_feature(dev, DRIVER_COMPUTE_ACCEL) &&
625 (drm_core_check_feature(dev, DRIVER_RENDER) ||
626 drm_core_check_feature(dev, DRIVER_MODESET))) {
627 DRM_ERROR("DRM driver can't be both a compute acceleration and graphics driver\n");
628 return -EINVAL;
629 }
630
631 INIT_LIST_HEAD(&dev->filelist);
632 INIT_LIST_HEAD(&dev->filelist_internal);
633 INIT_LIST_HEAD(&dev->clientlist);
634 INIT_LIST_HEAD(&dev->vblank_event_list);
635
636 spin_lock_init(&dev->event_lock);
637 mutex_init(&dev->struct_mutex);
638 mutex_init(&dev->filelist_mutex);
639 mutex_init(&dev->clientlist_mutex);
640 mutex_init(&dev->master_mutex);
641
642 ret = drmm_add_action_or_reset(dev, drm_dev_init_release, NULL);
643 if (ret)
644 return ret;
645
646 inode = drm_fs_inode_new();
647 if (IS_ERR(inode)) {
648 ret = PTR_ERR(inode);
649 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
650 goto err;
651 }
652
653 dev->anon_inode = inode;
654
655 if (drm_core_check_feature(dev, DRIVER_COMPUTE_ACCEL)) {
656 ret = drm_minor_alloc(dev, DRM_MINOR_ACCEL);
657 if (ret)
658 goto err;
659 } else {
660 if (drm_core_check_feature(dev, DRIVER_RENDER)) {
661 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
662 if (ret)
663 goto err;
664 }
665
666 ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY);
667 if (ret)
668 goto err;
669 }
670
671 if (drm_core_check_feature(dev, DRIVER_GEM)) {
672 ret = drm_gem_init(dev);
673 if (ret) {
674 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
675 goto err;
676 }
677 }
678
679 dev->unique = drmm_kstrdup(dev, dev_name(parent), GFP_KERNEL);
680 if (!dev->unique) {
681 ret = -ENOMEM;
682 goto err;
683 }
684
685 if (drm_core_check_feature(dev, DRIVER_COMPUTE_ACCEL))
686 accel_debugfs_init(dev);
687 else
688 drm_debugfs_dev_init(dev, drm_debugfs_root);
689
690 return 0;
691
692err:
693 drm_managed_release(dev);
694
695 return ret;
696}
697
698static void devm_drm_dev_init_release(void *data)
699{
700 drm_dev_put(data);
701}
702
703static int devm_drm_dev_init(struct device *parent,
704 struct drm_device *dev,
705 const struct drm_driver *driver)
706{
707 int ret;
708
709 ret = drm_dev_init(dev, driver, parent);
710 if (ret)
711 return ret;
712
713 return devm_add_action_or_reset(parent,
714 devm_drm_dev_init_release, dev);
715}
716
717void *__devm_drm_dev_alloc(struct device *parent,
718 const struct drm_driver *driver,
719 size_t size, size_t offset)
720{
721 void *container;
722 struct drm_device *drm;
723 int ret;
724
725 container = kzalloc(size, GFP_KERNEL);
726 if (!container)
727 return ERR_PTR(-ENOMEM);
728
729 drm = container + offset;
730 ret = devm_drm_dev_init(parent, drm, driver);
731 if (ret) {
732 kfree(container);
733 return ERR_PTR(ret);
734 }
735 drmm_add_final_kfree(drm, container);
736
737 return container;
738}
739EXPORT_SYMBOL(__devm_drm_dev_alloc);
740
741/**
742 * drm_dev_alloc - Allocate new DRM device
743 * @driver: DRM driver to allocate device for
744 * @parent: Parent device object
745 *
746 * This is the deprecated version of devm_drm_dev_alloc(), which does not support
747 * subclassing through embedding the struct &drm_device in a driver private
748 * structure, and which does not support automatic cleanup through devres.
749 *
750 * RETURNS:
751 * Pointer to new DRM device, or ERR_PTR on failure.
752 */
753struct drm_device *drm_dev_alloc(const struct drm_driver *driver,
754 struct device *parent)
755{
756 struct drm_device *dev;
757 int ret;
758
759 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
760 if (!dev)
761 return ERR_PTR(-ENOMEM);
762
763 ret = drm_dev_init(dev, driver, parent);
764 if (ret) {
765 kfree(dev);
766 return ERR_PTR(ret);
767 }
768
769 drmm_add_final_kfree(dev, dev);
770
771 return dev;
772}
773EXPORT_SYMBOL(drm_dev_alloc);
774
775static void drm_dev_release(struct kref *ref)
776{
777 struct drm_device *dev = container_of(ref, struct drm_device, ref);
778
779 /* Just in case register/unregister was never called */
780 drm_debugfs_dev_fini(dev);
781
782 if (dev->driver->release)
783 dev->driver->release(dev);
784
785 drm_managed_release(dev);
786
787 kfree(dev->managed.final_kfree);
788}
789
790/**
791 * drm_dev_get - Take reference of a DRM device
792 * @dev: device to take reference of or NULL
793 *
794 * This increases the ref-count of @dev by one. You *must* already own a
795 * reference when calling this. Use drm_dev_put() to drop this reference
796 * again.
797 *
798 * This function never fails. However, this function does not provide *any*
799 * guarantee whether the device is alive or running. It only provides a
800 * reference to the object and the memory associated with it.
801 */
802void drm_dev_get(struct drm_device *dev)
803{
804 if (dev)
805 kref_get(&dev->ref);
806}
807EXPORT_SYMBOL(drm_dev_get);
808
809/**
810 * drm_dev_put - Drop reference of a DRM device
811 * @dev: device to drop reference of or NULL
812 *
813 * This decreases the ref-count of @dev by one. The device is destroyed if the
814 * ref-count drops to zero.
815 */
816void drm_dev_put(struct drm_device *dev)
817{
818 if (dev)
819 kref_put(&dev->ref, drm_dev_release);
820}
821EXPORT_SYMBOL(drm_dev_put);
822
823static int create_compat_control_link(struct drm_device *dev)
824{
825 struct drm_minor *minor;
826 char *name;
827 int ret;
828
829 if (!drm_core_check_feature(dev, DRIVER_MODESET))
830 return 0;
831
832 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
833 if (!minor)
834 return 0;
835
836 /*
837 * Some existing userspace out there uses the existing of the controlD*
838 * sysfs files to figure out whether it's a modeset driver. It only does
839 * readdir, hence a symlink is sufficient (and the least confusing
840 * option). Otherwise controlD* is entirely unused.
841 *
842 * Old controlD chardev have been allocated in the range
843 * 64-127.
844 */
845 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
846 if (!name)
847 return -ENOMEM;
848
849 ret = sysfs_create_link(minor->kdev->kobj.parent,
850 &minor->kdev->kobj,
851 name);
852
853 kfree(name);
854
855 return ret;
856}
857
858static void remove_compat_control_link(struct drm_device *dev)
859{
860 struct drm_minor *minor;
861 char *name;
862
863 if (!drm_core_check_feature(dev, DRIVER_MODESET))
864 return;
865
866 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
867 if (!minor)
868 return;
869
870 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
871 if (!name)
872 return;
873
874 sysfs_remove_link(minor->kdev->kobj.parent, name);
875
876 kfree(name);
877}
878
879/**
880 * drm_dev_register - Register DRM device
881 * @dev: Device to register
882 * @flags: Flags passed to the driver's .load() function
883 *
884 * Register the DRM device @dev with the system, advertise device to user-space
885 * and start normal device operation. @dev must be initialized via drm_dev_init()
886 * previously.
887 *
888 * Never call this twice on any device!
889 *
890 * NOTE: To ensure backward compatibility with existing drivers method this
891 * function calls the &drm_driver.load method after registering the device
892 * nodes, creating race conditions. Usage of the &drm_driver.load methods is
893 * therefore deprecated, drivers must perform all initialization before calling
894 * drm_dev_register().
895 *
896 * RETURNS:
897 * 0 on success, negative error code on failure.
898 */
899int drm_dev_register(struct drm_device *dev, unsigned long flags)
900{
901 const struct drm_driver *driver = dev->driver;
902 int ret;
903
904 if (!driver->load)
905 drm_mode_config_validate(dev);
906
907 WARN_ON(!dev->managed.final_kfree);
908
909 if (drm_dev_needs_global_mutex(dev))
910 mutex_lock(&drm_global_mutex);
911
912 if (drm_core_check_feature(dev, DRIVER_COMPUTE_ACCEL))
913 accel_debugfs_register(dev);
914 else
915 drm_debugfs_dev_register(dev);
916
917 ret = drm_minor_register(dev, DRM_MINOR_RENDER);
918 if (ret)
919 goto err_minors;
920
921 ret = drm_minor_register(dev, DRM_MINOR_PRIMARY);
922 if (ret)
923 goto err_minors;
924
925 ret = drm_minor_register(dev, DRM_MINOR_ACCEL);
926 if (ret)
927 goto err_minors;
928
929 ret = create_compat_control_link(dev);
930 if (ret)
931 goto err_minors;
932
933 dev->registered = true;
934
935 if (driver->load) {
936 ret = driver->load(dev, flags);
937 if (ret)
938 goto err_minors;
939 }
940
941 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
942 ret = drm_modeset_register_all(dev);
943 if (ret)
944 goto err_unload;
945 }
946
947 DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
948 driver->name, driver->major, driver->minor,
949 driver->patchlevel, driver->date,
950 dev->dev ? dev_name(dev->dev) : "virtual device",
951 dev->primary ? dev->primary->index : dev->accel->index);
952
953 goto out_unlock;
954
955err_unload:
956 if (dev->driver->unload)
957 dev->driver->unload(dev);
958err_minors:
959 remove_compat_control_link(dev);
960 drm_minor_unregister(dev, DRM_MINOR_ACCEL);
961 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
962 drm_minor_unregister(dev, DRM_MINOR_RENDER);
963out_unlock:
964 if (drm_dev_needs_global_mutex(dev))
965 mutex_unlock(&drm_global_mutex);
966 return ret;
967}
968EXPORT_SYMBOL(drm_dev_register);
969
970/**
971 * drm_dev_unregister - Unregister DRM device
972 * @dev: Device to unregister
973 *
974 * Unregister the DRM device from the system. This does the reverse of
975 * drm_dev_register() but does not deallocate the device. The caller must call
976 * drm_dev_put() to drop their final reference, unless it is managed with devres
977 * (as devices allocated with devm_drm_dev_alloc() are), in which case there is
978 * already an unwind action registered.
979 *
980 * A special form of unregistering for hotpluggable devices is drm_dev_unplug(),
981 * which can be called while there are still open users of @dev.
982 *
983 * This should be called first in the device teardown code to make sure
984 * userspace can't access the device instance any more.
985 */
986void drm_dev_unregister(struct drm_device *dev)
987{
988 dev->registered = false;
989
990 drm_client_dev_unregister(dev);
991
992 if (drm_core_check_feature(dev, DRIVER_MODESET))
993 drm_modeset_unregister_all(dev);
994
995 if (dev->driver->unload)
996 dev->driver->unload(dev);
997
998 remove_compat_control_link(dev);
999 drm_minor_unregister(dev, DRM_MINOR_ACCEL);
1000 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
1001 drm_minor_unregister(dev, DRM_MINOR_RENDER);
1002 drm_debugfs_dev_fini(dev);
1003}
1004EXPORT_SYMBOL(drm_dev_unregister);
1005
1006/*
1007 * DRM Core
1008 * The DRM core module initializes all global DRM objects and makes them
1009 * available to drivers. Once setup, drivers can probe their respective
1010 * devices.
1011 * Currently, core management includes:
1012 * - The "DRM-Global" key/value database
1013 * - Global ID management for connectors
1014 * - DRM major number allocation
1015 * - DRM minor management
1016 * - DRM sysfs class
1017 * - DRM debugfs root
1018 *
1019 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
1020 * interface registered on a DRM device, you can request minor numbers from DRM
1021 * core. DRM core takes care of major-number management and char-dev
1022 * registration. A stub ->open() callback forwards any open() requests to the
1023 * registered minor.
1024 */
1025
1026static int drm_stub_open(struct inode *inode, struct file *filp)
1027{
1028 const struct file_operations *new_fops;
1029 struct drm_minor *minor;
1030 int err;
1031
1032 DRM_DEBUG("\n");
1033
1034 minor = drm_minor_acquire(iminor(inode));
1035 if (IS_ERR(minor))
1036 return PTR_ERR(minor);
1037
1038 new_fops = fops_get(minor->dev->driver->fops);
1039 if (!new_fops) {
1040 err = -ENODEV;
1041 goto out;
1042 }
1043
1044 replace_fops(filp, new_fops);
1045 if (filp->f_op->open)
1046 err = filp->f_op->open(inode, filp);
1047 else
1048 err = 0;
1049
1050out:
1051 drm_minor_release(minor);
1052
1053 return err;
1054}
1055
1056static const struct file_operations drm_stub_fops = {
1057 .owner = THIS_MODULE,
1058 .open = drm_stub_open,
1059 .llseek = noop_llseek,
1060};
1061
1062static void drm_core_exit(void)
1063{
1064 drm_privacy_screen_lookup_exit();
1065 accel_core_exit();
1066 unregister_chrdev(DRM_MAJOR, "drm");
1067 debugfs_remove(drm_debugfs_root);
1068 drm_sysfs_destroy();
1069 idr_destroy(&drm_minors_idr);
1070 drm_connector_ida_destroy();
1071}
1072
1073static int __init drm_core_init(void)
1074{
1075 int ret;
1076
1077 drm_connector_ida_init();
1078 idr_init(&drm_minors_idr);
1079 drm_memcpy_init_early();
1080
1081 ret = drm_sysfs_init();
1082 if (ret < 0) {
1083 DRM_ERROR("Cannot create DRM class: %d\n", ret);
1084 goto error;
1085 }
1086
1087 drm_debugfs_root = debugfs_create_dir("dri", NULL);
1088
1089 ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops);
1090 if (ret < 0)
1091 goto error;
1092
1093 ret = accel_core_init();
1094 if (ret < 0)
1095 goto error;
1096
1097 drm_privacy_screen_lookup_init();
1098
1099 drm_core_init_complete = true;
1100
1101 DRM_DEBUG("Initialized\n");
1102 return 0;
1103
1104error:
1105 drm_core_exit();
1106 return ret;
1107}
1108
1109module_init(drm_core_init);
1110module_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/slab.h>
35
36#include <drm/drm_drv.h>
37#include <drm/drmP.h>
38
39#include "drm_crtc_internal.h"
40#include "drm_legacy.h"
41#include "drm_internal.h"
42#include "drm_crtc_internal.h"
43
44/*
45 * drm_debug: Enable debug output.
46 * Bitmask of DRM_UT_x. See include/drm/drmP.h for details.
47 */
48unsigned int drm_debug = 0;
49EXPORT_SYMBOL(drm_debug);
50
51MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl");
52MODULE_DESCRIPTION("DRM shared core routines");
53MODULE_LICENSE("GPL and additional rights");
54MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
55"\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n"
56"\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n"
57"\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n"
58"\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n"
59"\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n"
60"\t\tBit 5 (0x20) will enable VBL messages (vblank code)\n"
61"\t\tBit 7 (0x80) will enable LEASE messages (leasing code)");
62module_param_named(debug, drm_debug, int, 0600);
63
64static DEFINE_SPINLOCK(drm_minor_lock);
65static struct idr drm_minors_idr;
66
67/*
68 * If the drm core fails to init for whatever reason,
69 * we should prevent any drivers from registering with it.
70 * It's best to check this at drm_dev_init(), as some drivers
71 * prefer to embed struct drm_device into their own device
72 * structure and call drm_dev_init() themselves.
73 */
74static bool drm_core_init_complete = false;
75
76static struct dentry *drm_debugfs_root;
77
78/*
79 * DRM Minors
80 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
81 * of them is represented by a drm_minor object. Depending on the capabilities
82 * of the device-driver, different interfaces are registered.
83 *
84 * Minors can be accessed via dev->$minor_name. This pointer is either
85 * NULL or a valid drm_minor pointer and stays valid as long as the device is
86 * valid. This means, DRM minors have the same life-time as the underlying
87 * device. However, this doesn't mean that the minor is active. Minors are
88 * registered and unregistered dynamically according to device-state.
89 */
90
91static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
92 unsigned int type)
93{
94 switch (type) {
95 case DRM_MINOR_PRIMARY:
96 return &dev->primary;
97 case DRM_MINOR_RENDER:
98 return &dev->render;
99 case DRM_MINOR_CONTROL:
100 return &dev->control;
101 default:
102 BUG();
103 }
104}
105
106static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
107{
108 struct drm_minor *minor;
109 unsigned long flags;
110 int r;
111
112 minor = kzalloc(sizeof(*minor), GFP_KERNEL);
113 if (!minor)
114 return -ENOMEM;
115
116 minor->type = type;
117 minor->dev = dev;
118
119 idr_preload(GFP_KERNEL);
120 spin_lock_irqsave(&drm_minor_lock, flags);
121 r = idr_alloc(&drm_minors_idr,
122 NULL,
123 64 * type,
124 64 * (type + 1),
125 GFP_NOWAIT);
126 spin_unlock_irqrestore(&drm_minor_lock, flags);
127 idr_preload_end();
128
129 if (r < 0)
130 goto err_free;
131
132 minor->index = r;
133
134 minor->kdev = drm_sysfs_minor_alloc(minor);
135 if (IS_ERR(minor->kdev)) {
136 r = PTR_ERR(minor->kdev);
137 goto err_index;
138 }
139
140 *drm_minor_get_slot(dev, type) = minor;
141 return 0;
142
143err_index:
144 spin_lock_irqsave(&drm_minor_lock, flags);
145 idr_remove(&drm_minors_idr, minor->index);
146 spin_unlock_irqrestore(&drm_minor_lock, flags);
147err_free:
148 kfree(minor);
149 return r;
150}
151
152static void drm_minor_free(struct drm_device *dev, unsigned int type)
153{
154 struct drm_minor **slot, *minor;
155 unsigned long flags;
156
157 slot = drm_minor_get_slot(dev, type);
158 minor = *slot;
159 if (!minor)
160 return;
161
162 put_device(minor->kdev);
163
164 spin_lock_irqsave(&drm_minor_lock, flags);
165 idr_remove(&drm_minors_idr, minor->index);
166 spin_unlock_irqrestore(&drm_minor_lock, flags);
167
168 kfree(minor);
169 *slot = NULL;
170}
171
172static int drm_minor_register(struct drm_device *dev, unsigned int type)
173{
174 struct drm_minor *minor;
175 unsigned long flags;
176 int ret;
177
178 DRM_DEBUG("\n");
179
180 minor = *drm_minor_get_slot(dev, type);
181 if (!minor)
182 return 0;
183
184 ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root);
185 if (ret) {
186 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
187 goto err_debugfs;
188 }
189
190 ret = device_add(minor->kdev);
191 if (ret)
192 goto err_debugfs;
193
194 /* replace NULL with @minor so lookups will succeed from now on */
195 spin_lock_irqsave(&drm_minor_lock, flags);
196 idr_replace(&drm_minors_idr, minor, minor->index);
197 spin_unlock_irqrestore(&drm_minor_lock, flags);
198
199 DRM_DEBUG("new minor registered %d\n", minor->index);
200 return 0;
201
202err_debugfs:
203 drm_debugfs_cleanup(minor);
204 return ret;
205}
206
207static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
208{
209 struct drm_minor *minor;
210 unsigned long flags;
211
212 minor = *drm_minor_get_slot(dev, type);
213 if (!minor || !device_is_registered(minor->kdev))
214 return;
215
216 /* replace @minor with NULL so lookups will fail from now on */
217 spin_lock_irqsave(&drm_minor_lock, flags);
218 idr_replace(&drm_minors_idr, NULL, minor->index);
219 spin_unlock_irqrestore(&drm_minor_lock, flags);
220
221 device_del(minor->kdev);
222 dev_set_drvdata(minor->kdev, NULL); /* safety belt */
223 drm_debugfs_cleanup(minor);
224}
225
226/*
227 * Looks up the given minor-ID and returns the respective DRM-minor object. The
228 * refence-count of the underlying device is increased so you must release this
229 * object with drm_minor_release().
230 *
231 * As long as you hold this minor, it is guaranteed that the object and the
232 * minor->dev pointer will stay valid! However, the device may get unplugged and
233 * unregistered while you hold the minor.
234 */
235struct drm_minor *drm_minor_acquire(unsigned int minor_id)
236{
237 struct drm_minor *minor;
238 unsigned long flags;
239
240 spin_lock_irqsave(&drm_minor_lock, flags);
241 minor = idr_find(&drm_minors_idr, minor_id);
242 if (minor)
243 drm_dev_get(minor->dev);
244 spin_unlock_irqrestore(&drm_minor_lock, flags);
245
246 if (!minor) {
247 return ERR_PTR(-ENODEV);
248 } else if (drm_dev_is_unplugged(minor->dev)) {
249 drm_dev_put(minor->dev);
250 return ERR_PTR(-ENODEV);
251 }
252
253 return minor;
254}
255
256void drm_minor_release(struct drm_minor *minor)
257{
258 drm_dev_put(minor->dev);
259}
260
261/**
262 * DOC: driver instance overview
263 *
264 * A device instance for a drm driver is represented by &struct drm_device. This
265 * is allocated with drm_dev_alloc(), usually from bus-specific ->probe()
266 * callbacks implemented by the driver. The driver then needs to initialize all
267 * the various subsystems for the drm device like memory management, vblank
268 * handling, modesetting support and intial output configuration plus obviously
269 * initialize all the corresponding hardware bits. An important part of this is
270 * also calling drm_dev_set_unique() to set the userspace-visible unique name of
271 * this device instance. Finally when everything is up and running and ready for
272 * userspace the device instance can be published using drm_dev_register().
273 *
274 * There is also deprecated support for initalizing device instances using
275 * bus-specific helpers and the &drm_driver.load callback. But due to
276 * backwards-compatibility needs the device instance have to be published too
277 * early, which requires unpretty global locking to make safe and is therefore
278 * only support for existing drivers not yet converted to the new scheme.
279 *
280 * When cleaning up a device instance everything needs to be done in reverse:
281 * First unpublish the device instance with drm_dev_unregister(). Then clean up
282 * any other resources allocated at device initialization and drop the driver's
283 * reference to &drm_device using drm_dev_put().
284 *
285 * Note that the lifetime rules for &drm_device instance has still a lot of
286 * historical baggage. Hence use the reference counting provided by
287 * drm_dev_get() and drm_dev_put() only carefully.
288 *
289 * It is recommended that drivers embed &struct drm_device into their own device
290 * structure, which is supported through drm_dev_init().
291 */
292
293/**
294 * drm_put_dev - Unregister and release a DRM device
295 * @dev: DRM device
296 *
297 * Called at module unload time or when a PCI device is unplugged.
298 *
299 * Cleans up all DRM device, calling drm_lastclose().
300 *
301 * Note: Use of this function is deprecated. It will eventually go away
302 * completely. Please use drm_dev_unregister() and drm_dev_put() explicitly
303 * instead to make sure that the device isn't userspace accessible any more
304 * while teardown is in progress, ensuring that userspace can't access an
305 * inconsistent state.
306 */
307void drm_put_dev(struct drm_device *dev)
308{
309 DRM_DEBUG("\n");
310
311 if (!dev) {
312 DRM_ERROR("cleanup called no dev\n");
313 return;
314 }
315
316 drm_dev_unregister(dev);
317 drm_dev_put(dev);
318}
319EXPORT_SYMBOL(drm_put_dev);
320
321static void drm_device_set_unplugged(struct drm_device *dev)
322{
323 smp_wmb();
324 atomic_set(&dev->unplugged, 1);
325}
326
327/**
328 * drm_dev_unplug - unplug a DRM device
329 * @dev: DRM device
330 *
331 * This unplugs a hotpluggable DRM device, which makes it inaccessible to
332 * userspace operations. Entry-points can use drm_dev_is_unplugged(). This
333 * essentially unregisters the device like drm_dev_unregister(), but can be
334 * called while there are still open users of @dev.
335 */
336void drm_dev_unplug(struct drm_device *dev)
337{
338 drm_dev_unregister(dev);
339
340 mutex_lock(&drm_global_mutex);
341 drm_device_set_unplugged(dev);
342 if (dev->open_count == 0)
343 drm_dev_put(dev);
344 mutex_unlock(&drm_global_mutex);
345}
346EXPORT_SYMBOL(drm_dev_unplug);
347
348/*
349 * DRM internal mount
350 * We want to be able to allocate our own "struct address_space" to control
351 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
352 * stand-alone address_space objects, so we need an underlying inode. As there
353 * is no way to allocate an independent inode easily, we need a fake internal
354 * VFS mount-point.
355 *
356 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
357 * frees it again. You are allowed to use iget() and iput() to get references to
358 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
359 * drm_fs_inode_free() call (which does not have to be the last iput()).
360 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
361 * between multiple inode-users. You could, technically, call
362 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
363 * iput(), but this way you'd end up with a new vfsmount for each inode.
364 */
365
366static int drm_fs_cnt;
367static struct vfsmount *drm_fs_mnt;
368
369static const struct dentry_operations drm_fs_dops = {
370 .d_dname = simple_dname,
371};
372
373static const struct super_operations drm_fs_sops = {
374 .statfs = simple_statfs,
375};
376
377static struct dentry *drm_fs_mount(struct file_system_type *fs_type, int flags,
378 const char *dev_name, void *data)
379{
380 return mount_pseudo(fs_type,
381 "drm:",
382 &drm_fs_sops,
383 &drm_fs_dops,
384 0x010203ff);
385}
386
387static struct file_system_type drm_fs_type = {
388 .name = "drm",
389 .owner = THIS_MODULE,
390 .mount = drm_fs_mount,
391 .kill_sb = kill_anon_super,
392};
393
394static struct inode *drm_fs_inode_new(void)
395{
396 struct inode *inode;
397 int r;
398
399 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
400 if (r < 0) {
401 DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
402 return ERR_PTR(r);
403 }
404
405 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
406 if (IS_ERR(inode))
407 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
408
409 return inode;
410}
411
412static void drm_fs_inode_free(struct inode *inode)
413{
414 if (inode) {
415 iput(inode);
416 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
417 }
418}
419
420/**
421 * drm_dev_init - Initialise new DRM device
422 * @dev: DRM device
423 * @driver: DRM driver
424 * @parent: Parent device object
425 *
426 * Initialize a new DRM device. No device registration is done.
427 * Call drm_dev_register() to advertice the device to user space and register it
428 * with other core subsystems. This should be done last in the device
429 * initialization sequence to make sure userspace can't access an inconsistent
430 * state.
431 *
432 * The initial ref-count of the object is 1. Use drm_dev_get() and
433 * drm_dev_put() to take and drop further ref-counts.
434 *
435 * Note that for purely virtual devices @parent can be NULL.
436 *
437 * Drivers that do not want to allocate their own device struct
438 * embedding &struct drm_device can call drm_dev_alloc() instead. For drivers
439 * that do embed &struct drm_device it must be placed first in the overall
440 * structure, and the overall structure must be allocated using kmalloc(): The
441 * drm core's release function unconditionally calls kfree() on the @dev pointer
442 * when the final reference is released. To override this behaviour, and so
443 * allow embedding of the drm_device inside the driver's device struct at an
444 * arbitrary offset, you must supply a &drm_driver.release callback and control
445 * the finalization explicitly.
446 *
447 * RETURNS:
448 * 0 on success, or error code on failure.
449 */
450int drm_dev_init(struct drm_device *dev,
451 struct drm_driver *driver,
452 struct device *parent)
453{
454 int ret;
455
456 if (!drm_core_init_complete) {
457 DRM_ERROR("DRM core is not initialized\n");
458 return -ENODEV;
459 }
460
461 kref_init(&dev->ref);
462 dev->dev = parent;
463 dev->driver = driver;
464
465 INIT_LIST_HEAD(&dev->filelist);
466 INIT_LIST_HEAD(&dev->ctxlist);
467 INIT_LIST_HEAD(&dev->vmalist);
468 INIT_LIST_HEAD(&dev->maplist);
469 INIT_LIST_HEAD(&dev->vblank_event_list);
470
471 spin_lock_init(&dev->buf_lock);
472 spin_lock_init(&dev->event_lock);
473 mutex_init(&dev->struct_mutex);
474 mutex_init(&dev->filelist_mutex);
475 mutex_init(&dev->ctxlist_mutex);
476 mutex_init(&dev->master_mutex);
477
478 dev->anon_inode = drm_fs_inode_new();
479 if (IS_ERR(dev->anon_inode)) {
480 ret = PTR_ERR(dev->anon_inode);
481 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
482 goto err_free;
483 }
484
485 if (drm_core_check_feature(dev, DRIVER_RENDER)) {
486 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
487 if (ret)
488 goto err_minors;
489 }
490
491 ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY);
492 if (ret)
493 goto err_minors;
494
495 ret = drm_ht_create(&dev->map_hash, 12);
496 if (ret)
497 goto err_minors;
498
499 drm_legacy_ctxbitmap_init(dev);
500
501 if (drm_core_check_feature(dev, DRIVER_GEM)) {
502 ret = drm_gem_init(dev);
503 if (ret) {
504 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
505 goto err_ctxbitmap;
506 }
507 }
508
509 /* Use the parent device name as DRM device unique identifier, but fall
510 * back to the driver name for virtual devices like vgem. */
511 ret = drm_dev_set_unique(dev, parent ? dev_name(parent) : driver->name);
512 if (ret)
513 goto err_setunique;
514
515 return 0;
516
517err_setunique:
518 if (drm_core_check_feature(dev, DRIVER_GEM))
519 drm_gem_destroy(dev);
520err_ctxbitmap:
521 drm_legacy_ctxbitmap_cleanup(dev);
522 drm_ht_remove(&dev->map_hash);
523err_minors:
524 drm_minor_free(dev, DRM_MINOR_PRIMARY);
525 drm_minor_free(dev, DRM_MINOR_RENDER);
526 drm_minor_free(dev, DRM_MINOR_CONTROL);
527 drm_fs_inode_free(dev->anon_inode);
528err_free:
529 mutex_destroy(&dev->master_mutex);
530 mutex_destroy(&dev->ctxlist_mutex);
531 mutex_destroy(&dev->filelist_mutex);
532 mutex_destroy(&dev->struct_mutex);
533 return ret;
534}
535EXPORT_SYMBOL(drm_dev_init);
536
537/**
538 * drm_dev_fini - Finalize a dead DRM device
539 * @dev: DRM device
540 *
541 * Finalize a dead DRM device. This is the converse to drm_dev_init() and
542 * frees up all data allocated by it. All driver private data should be
543 * finalized first. Note that this function does not free the @dev, that is
544 * left to the caller.
545 *
546 * The ref-count of @dev must be zero, and drm_dev_fini() should only be called
547 * from a &drm_driver.release callback.
548 */
549void drm_dev_fini(struct drm_device *dev)
550{
551 drm_vblank_cleanup(dev);
552
553 if (drm_core_check_feature(dev, DRIVER_GEM))
554 drm_gem_destroy(dev);
555
556 drm_legacy_ctxbitmap_cleanup(dev);
557 drm_ht_remove(&dev->map_hash);
558 drm_fs_inode_free(dev->anon_inode);
559
560 drm_minor_free(dev, DRM_MINOR_PRIMARY);
561 drm_minor_free(dev, DRM_MINOR_RENDER);
562 drm_minor_free(dev, DRM_MINOR_CONTROL);
563
564 mutex_destroy(&dev->master_mutex);
565 mutex_destroy(&dev->ctxlist_mutex);
566 mutex_destroy(&dev->filelist_mutex);
567 mutex_destroy(&dev->struct_mutex);
568 kfree(dev->unique);
569}
570EXPORT_SYMBOL(drm_dev_fini);
571
572/**
573 * drm_dev_alloc - Allocate new DRM device
574 * @driver: DRM driver to allocate device for
575 * @parent: Parent device object
576 *
577 * Allocate and initialize a new DRM device. No device registration is done.
578 * Call drm_dev_register() to advertice the device to user space and register it
579 * with other core subsystems. This should be done last in the device
580 * initialization sequence to make sure userspace can't access an inconsistent
581 * state.
582 *
583 * The initial ref-count of the object is 1. Use drm_dev_get() and
584 * drm_dev_put() to take and drop further ref-counts.
585 *
586 * Note that for purely virtual devices @parent can be NULL.
587 *
588 * Drivers that wish to subclass or embed &struct drm_device into their
589 * own struct should look at using drm_dev_init() instead.
590 *
591 * RETURNS:
592 * Pointer to new DRM device, or ERR_PTR on failure.
593 */
594struct drm_device *drm_dev_alloc(struct drm_driver *driver,
595 struct device *parent)
596{
597 struct drm_device *dev;
598 int ret;
599
600 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
601 if (!dev)
602 return ERR_PTR(-ENOMEM);
603
604 ret = drm_dev_init(dev, driver, parent);
605 if (ret) {
606 kfree(dev);
607 return ERR_PTR(ret);
608 }
609
610 return dev;
611}
612EXPORT_SYMBOL(drm_dev_alloc);
613
614static void drm_dev_release(struct kref *ref)
615{
616 struct drm_device *dev = container_of(ref, struct drm_device, ref);
617
618 if (dev->driver->release) {
619 dev->driver->release(dev);
620 } else {
621 drm_dev_fini(dev);
622 kfree(dev);
623 }
624}
625
626/**
627 * drm_dev_get - Take reference of a DRM device
628 * @dev: device to take reference of or NULL
629 *
630 * This increases the ref-count of @dev by one. You *must* already own a
631 * reference when calling this. Use drm_dev_put() to drop this reference
632 * again.
633 *
634 * This function never fails. However, this function does not provide *any*
635 * guarantee whether the device is alive or running. It only provides a
636 * reference to the object and the memory associated with it.
637 */
638void drm_dev_get(struct drm_device *dev)
639{
640 if (dev)
641 kref_get(&dev->ref);
642}
643EXPORT_SYMBOL(drm_dev_get);
644
645/**
646 * drm_dev_put - Drop reference of a DRM device
647 * @dev: device to drop reference of or NULL
648 *
649 * This decreases the ref-count of @dev by one. The device is destroyed if the
650 * ref-count drops to zero.
651 */
652void drm_dev_put(struct drm_device *dev)
653{
654 if (dev)
655 kref_put(&dev->ref, drm_dev_release);
656}
657EXPORT_SYMBOL(drm_dev_put);
658
659/**
660 * drm_dev_unref - Drop reference of a DRM device
661 * @dev: device to drop reference of or NULL
662 *
663 * This is a compatibility alias for drm_dev_put() and should not be used by new
664 * code.
665 */
666void drm_dev_unref(struct drm_device *dev)
667{
668 drm_dev_put(dev);
669}
670EXPORT_SYMBOL(drm_dev_unref);
671
672static int create_compat_control_link(struct drm_device *dev)
673{
674 struct drm_minor *minor;
675 char *name;
676 int ret;
677
678 if (!drm_core_check_feature(dev, DRIVER_MODESET))
679 return 0;
680
681 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
682 if (!minor)
683 return 0;
684
685 /*
686 * Some existing userspace out there uses the existing of the controlD*
687 * sysfs files to figure out whether it's a modeset driver. It only does
688 * readdir, hence a symlink is sufficient (and the least confusing
689 * option). Otherwise controlD* is entirely unused.
690 *
691 * Old controlD chardev have been allocated in the range
692 * 64-127.
693 */
694 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
695 if (!name)
696 return -ENOMEM;
697
698 ret = sysfs_create_link(minor->kdev->kobj.parent,
699 &minor->kdev->kobj,
700 name);
701
702 kfree(name);
703
704 return ret;
705}
706
707static void remove_compat_control_link(struct drm_device *dev)
708{
709 struct drm_minor *minor;
710 char *name;
711
712 if (!drm_core_check_feature(dev, DRIVER_MODESET))
713 return;
714
715 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
716 if (!minor)
717 return;
718
719 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
720 if (!name)
721 return;
722
723 sysfs_remove_link(minor->kdev->kobj.parent, name);
724
725 kfree(name);
726}
727
728/**
729 * drm_dev_register - Register DRM device
730 * @dev: Device to register
731 * @flags: Flags passed to the driver's .load() function
732 *
733 * Register the DRM device @dev with the system, advertise device to user-space
734 * and start normal device operation. @dev must be allocated via drm_dev_alloc()
735 * previously.
736 *
737 * Never call this twice on any device!
738 *
739 * NOTE: To ensure backward compatibility with existing drivers method this
740 * function calls the &drm_driver.load method after registering the device
741 * nodes, creating race conditions. Usage of the &drm_driver.load methods is
742 * therefore deprecated, drivers must perform all initialization before calling
743 * drm_dev_register().
744 *
745 * RETURNS:
746 * 0 on success, negative error code on failure.
747 */
748int drm_dev_register(struct drm_device *dev, unsigned long flags)
749{
750 struct drm_driver *driver = dev->driver;
751 int ret;
752
753 mutex_lock(&drm_global_mutex);
754
755 ret = drm_minor_register(dev, DRM_MINOR_CONTROL);
756 if (ret)
757 goto err_minors;
758
759 ret = drm_minor_register(dev, DRM_MINOR_RENDER);
760 if (ret)
761 goto err_minors;
762
763 ret = drm_minor_register(dev, DRM_MINOR_PRIMARY);
764 if (ret)
765 goto err_minors;
766
767 ret = create_compat_control_link(dev);
768 if (ret)
769 goto err_minors;
770
771 dev->registered = true;
772
773 if (dev->driver->load) {
774 ret = dev->driver->load(dev, flags);
775 if (ret)
776 goto err_minors;
777 }
778
779 if (drm_core_check_feature(dev, DRIVER_MODESET))
780 drm_modeset_register_all(dev);
781
782 ret = 0;
783
784 DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
785 driver->name, driver->major, driver->minor,
786 driver->patchlevel, driver->date,
787 dev->dev ? dev_name(dev->dev) : "virtual device",
788 dev->primary->index);
789
790 goto out_unlock;
791
792err_minors:
793 remove_compat_control_link(dev);
794 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
795 drm_minor_unregister(dev, DRM_MINOR_RENDER);
796 drm_minor_unregister(dev, DRM_MINOR_CONTROL);
797out_unlock:
798 mutex_unlock(&drm_global_mutex);
799 return ret;
800}
801EXPORT_SYMBOL(drm_dev_register);
802
803/**
804 * drm_dev_unregister - Unregister DRM device
805 * @dev: Device to unregister
806 *
807 * Unregister the DRM device from the system. This does the reverse of
808 * drm_dev_register() but does not deallocate the device. The caller must call
809 * drm_dev_put() to drop their final reference.
810 *
811 * A special form of unregistering for hotpluggable devices is drm_dev_unplug(),
812 * which can be called while there are still open users of @dev.
813 *
814 * This should be called first in the device teardown code to make sure
815 * userspace can't access the device instance any more.
816 */
817void drm_dev_unregister(struct drm_device *dev)
818{
819 struct drm_map_list *r_list, *list_temp;
820
821 if (drm_core_check_feature(dev, DRIVER_LEGACY))
822 drm_lastclose(dev);
823
824 dev->registered = false;
825
826 if (drm_core_check_feature(dev, DRIVER_MODESET))
827 drm_modeset_unregister_all(dev);
828
829 if (dev->driver->unload)
830 dev->driver->unload(dev);
831
832 if (dev->agp)
833 drm_pci_agp_destroy(dev);
834
835 list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
836 drm_legacy_rmmap(dev, r_list->map);
837
838 remove_compat_control_link(dev);
839 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
840 drm_minor_unregister(dev, DRM_MINOR_RENDER);
841 drm_minor_unregister(dev, DRM_MINOR_CONTROL);
842}
843EXPORT_SYMBOL(drm_dev_unregister);
844
845/**
846 * drm_dev_set_unique - Set the unique name of a DRM device
847 * @dev: device of which to set the unique name
848 * @name: unique name
849 *
850 * Sets the unique name of a DRM device using the specified string. Drivers
851 * can use this at driver probe time if the unique name of the devices they
852 * drive is static.
853 *
854 * Return: 0 on success or a negative error code on failure.
855 */
856int drm_dev_set_unique(struct drm_device *dev, const char *name)
857{
858 kfree(dev->unique);
859 dev->unique = kstrdup(name, GFP_KERNEL);
860
861 return dev->unique ? 0 : -ENOMEM;
862}
863EXPORT_SYMBOL(drm_dev_set_unique);
864
865/*
866 * DRM Core
867 * The DRM core module initializes all global DRM objects and makes them
868 * available to drivers. Once setup, drivers can probe their respective
869 * devices.
870 * Currently, core management includes:
871 * - The "DRM-Global" key/value database
872 * - Global ID management for connectors
873 * - DRM major number allocation
874 * - DRM minor management
875 * - DRM sysfs class
876 * - DRM debugfs root
877 *
878 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
879 * interface registered on a DRM device, you can request minor numbers from DRM
880 * core. DRM core takes care of major-number management and char-dev
881 * registration. A stub ->open() callback forwards any open() requests to the
882 * registered minor.
883 */
884
885static int drm_stub_open(struct inode *inode, struct file *filp)
886{
887 const struct file_operations *new_fops;
888 struct drm_minor *minor;
889 int err;
890
891 DRM_DEBUG("\n");
892
893 mutex_lock(&drm_global_mutex);
894 minor = drm_minor_acquire(iminor(inode));
895 if (IS_ERR(minor)) {
896 err = PTR_ERR(minor);
897 goto out_unlock;
898 }
899
900 new_fops = fops_get(minor->dev->driver->fops);
901 if (!new_fops) {
902 err = -ENODEV;
903 goto out_release;
904 }
905
906 replace_fops(filp, new_fops);
907 if (filp->f_op->open)
908 err = filp->f_op->open(inode, filp);
909 else
910 err = 0;
911
912out_release:
913 drm_minor_release(minor);
914out_unlock:
915 mutex_unlock(&drm_global_mutex);
916 return err;
917}
918
919static const struct file_operations drm_stub_fops = {
920 .owner = THIS_MODULE,
921 .open = drm_stub_open,
922 .llseek = noop_llseek,
923};
924
925static void drm_core_exit(void)
926{
927 unregister_chrdev(DRM_MAJOR, "drm");
928 debugfs_remove(drm_debugfs_root);
929 drm_sysfs_destroy();
930 idr_destroy(&drm_minors_idr);
931 drm_connector_ida_destroy();
932 drm_global_release();
933}
934
935static int __init drm_core_init(void)
936{
937 int ret;
938
939 drm_global_init();
940 drm_connector_ida_init();
941 idr_init(&drm_minors_idr);
942
943 ret = drm_sysfs_init();
944 if (ret < 0) {
945 DRM_ERROR("Cannot create DRM class: %d\n", ret);
946 goto error;
947 }
948
949 drm_debugfs_root = debugfs_create_dir("dri", NULL);
950 if (!drm_debugfs_root) {
951 ret = -ENOMEM;
952 DRM_ERROR("Cannot create debugfs-root: %d\n", ret);
953 goto error;
954 }
955
956 ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops);
957 if (ret < 0)
958 goto error;
959
960 drm_core_init_complete = true;
961
962 DRM_DEBUG("Initialized\n");
963 return 0;
964
965error:
966 drm_core_exit();
967 return ret;
968}
969
970module_init(drm_core_init);
971module_exit(drm_core_exit);