blob: 006e3b896caea7ed28a9c3df19bb5b134eef9ab9 [file] [log] [blame]
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001/*
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>
David Brazdil0f672f62019-12-10 10:32:29 +000034#include <linux/pseudo_fs.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000035#include <linux/slab.h>
36#include <linux/srcu.h>
37
38#include <drm/drm_client.h>
David Brazdil0f672f62019-12-10 10:32:29 +000039#include <drm/drm_color_mgmt.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000040#include <drm/drm_drv.h>
David Brazdil0f672f62019-12-10 10:32:29 +000041#include <drm/drm_file.h>
Olivier Deprez157378f2022-04-04 15:47:50 +020042#include <drm/drm_managed.h>
David Brazdil0f672f62019-12-10 10:32:29 +000043#include <drm/drm_mode_object.h>
44#include <drm/drm_print.h>
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000045
46#include "drm_crtc_internal.h"
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000047#include "drm_internal.h"
David Brazdil0f672f62019-12-10 10:32:29 +000048#include "drm_legacy.h"
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000049
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000050MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl");
51MODULE_DESCRIPTION("DRM shared core routines");
52MODULE_LICENSE("GPL and additional rights");
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000053
54static DEFINE_SPINLOCK(drm_minor_lock);
55static struct idr drm_minors_idr;
56
57/*
58 * If the drm core fails to init for whatever reason,
59 * we should prevent any drivers from registering with it.
60 * It's best to check this at drm_dev_init(), as some drivers
61 * prefer to embed struct drm_device into their own device
62 * structure and call drm_dev_init() themselves.
63 */
64static bool drm_core_init_complete = false;
65
66static struct dentry *drm_debugfs_root;
67
68DEFINE_STATIC_SRCU(drm_unplug_srcu);
69
70/*
71 * DRM Minors
72 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
73 * of them is represented by a drm_minor object. Depending on the capabilities
74 * of the device-driver, different interfaces are registered.
75 *
76 * Minors can be accessed via dev->$minor_name. This pointer is either
77 * NULL or a valid drm_minor pointer and stays valid as long as the device is
78 * valid. This means, DRM minors have the same life-time as the underlying
79 * device. However, this doesn't mean that the minor is active. Minors are
80 * registered and unregistered dynamically according to device-state.
81 */
82
83static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
84 unsigned int type)
85{
86 switch (type) {
87 case DRM_MINOR_PRIMARY:
88 return &dev->primary;
89 case DRM_MINOR_RENDER:
90 return &dev->render;
91 default:
92 BUG();
93 }
94}
95
Olivier Deprez157378f2022-04-04 15:47:50 +020096static void drm_minor_alloc_release(struct drm_device *dev, void *data)
97{
98 struct drm_minor *minor = data;
99 unsigned long flags;
100
101 WARN_ON(dev != minor->dev);
102
103 put_device(minor->kdev);
104
105 spin_lock_irqsave(&drm_minor_lock, flags);
106 idr_remove(&drm_minors_idr, minor->index);
107 spin_unlock_irqrestore(&drm_minor_lock, flags);
108}
109
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000110static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
111{
112 struct drm_minor *minor;
113 unsigned long flags;
114 int r;
115
Olivier Deprez157378f2022-04-04 15:47:50 +0200116 minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000117 if (!minor)
118 return -ENOMEM;
119
120 minor->type = type;
121 minor->dev = dev;
122
123 idr_preload(GFP_KERNEL);
124 spin_lock_irqsave(&drm_minor_lock, flags);
125 r = idr_alloc(&drm_minors_idr,
126 NULL,
127 64 * type,
128 64 * (type + 1),
129 GFP_NOWAIT);
130 spin_unlock_irqrestore(&drm_minor_lock, flags);
131 idr_preload_end();
132
133 if (r < 0)
Olivier Deprez157378f2022-04-04 15:47:50 +0200134 return r;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000135
136 minor->index = r;
137
Olivier Deprez157378f2022-04-04 15:47:50 +0200138 r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor);
139 if (r)
140 return r;
141
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000142 minor->kdev = drm_sysfs_minor_alloc(minor);
Olivier Deprez157378f2022-04-04 15:47:50 +0200143 if (IS_ERR(minor->kdev))
144 return PTR_ERR(minor->kdev);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000145
146 *drm_minor_get_slot(dev, type) = minor;
147 return 0;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000148}
149
150static int drm_minor_register(struct drm_device *dev, unsigned int type)
151{
152 struct drm_minor *minor;
153 unsigned long flags;
154 int ret;
155
156 DRM_DEBUG("\n");
157
158 minor = *drm_minor_get_slot(dev, type);
159 if (!minor)
160 return 0;
161
162 ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root);
163 if (ret) {
164 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
165 goto err_debugfs;
166 }
167
168 ret = device_add(minor->kdev);
169 if (ret)
170 goto err_debugfs;
171
172 /* replace NULL with @minor so lookups will succeed from now on */
173 spin_lock_irqsave(&drm_minor_lock, flags);
174 idr_replace(&drm_minors_idr, minor, minor->index);
175 spin_unlock_irqrestore(&drm_minor_lock, flags);
176
177 DRM_DEBUG("new minor registered %d\n", minor->index);
178 return 0;
179
180err_debugfs:
181 drm_debugfs_cleanup(minor);
182 return ret;
183}
184
185static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
186{
187 struct drm_minor *minor;
188 unsigned long flags;
189
190 minor = *drm_minor_get_slot(dev, type);
191 if (!minor || !device_is_registered(minor->kdev))
192 return;
193
194 /* replace @minor with NULL so lookups will fail from now on */
195 spin_lock_irqsave(&drm_minor_lock, flags);
196 idr_replace(&drm_minors_idr, NULL, minor->index);
197 spin_unlock_irqrestore(&drm_minor_lock, flags);
198
199 device_del(minor->kdev);
200 dev_set_drvdata(minor->kdev, NULL); /* safety belt */
201 drm_debugfs_cleanup(minor);
202}
203
204/*
205 * Looks up the given minor-ID and returns the respective DRM-minor object. The
206 * refence-count of the underlying device is increased so you must release this
207 * object with drm_minor_release().
208 *
209 * As long as you hold this minor, it is guaranteed that the object and the
210 * minor->dev pointer will stay valid! However, the device may get unplugged and
211 * unregistered while you hold the minor.
212 */
213struct drm_minor *drm_minor_acquire(unsigned int minor_id)
214{
215 struct drm_minor *minor;
216 unsigned long flags;
217
218 spin_lock_irqsave(&drm_minor_lock, flags);
219 minor = idr_find(&drm_minors_idr, minor_id);
220 if (minor)
221 drm_dev_get(minor->dev);
222 spin_unlock_irqrestore(&drm_minor_lock, flags);
223
224 if (!minor) {
225 return ERR_PTR(-ENODEV);
226 } else if (drm_dev_is_unplugged(minor->dev)) {
227 drm_dev_put(minor->dev);
228 return ERR_PTR(-ENODEV);
229 }
230
231 return minor;
232}
233
234void drm_minor_release(struct drm_minor *minor)
235{
236 drm_dev_put(minor->dev);
237}
238
239/**
240 * DOC: driver instance overview
241 *
242 * A device instance for a drm driver is represented by &struct drm_device. This
Olivier Deprez157378f2022-04-04 15:47:50 +0200243 * is allocated and initialized with devm_drm_dev_alloc(), usually from
244 * bus-specific ->probe() callbacks implemented by the driver. The driver then
245 * needs to initialize all the various subsystems for the drm device like memory
246 * management, vblank handling, modesetting support and initial output
247 * configuration plus obviously initialize all the corresponding hardware bits.
248 * Finally when everything is up and running and ready for userspace the device
249 * instance can be published using drm_dev_register().
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000250 *
251 * There is also deprecated support for initalizing device instances using
252 * bus-specific helpers and the &drm_driver.load callback. But due to
253 * backwards-compatibility needs the device instance have to be published too
254 * early, which requires unpretty global locking to make safe and is therefore
255 * only support for existing drivers not yet converted to the new scheme.
256 *
257 * When cleaning up a device instance everything needs to be done in reverse:
258 * First unpublish the device instance with drm_dev_unregister(). Then clean up
259 * any other resources allocated at device initialization and drop the driver's
260 * reference to &drm_device using drm_dev_put().
261 *
Olivier Deprez157378f2022-04-04 15:47:50 +0200262 * Note that any allocation or resource which is visible to userspace must be
263 * released only when the final drm_dev_put() is called, and not when the
264 * driver is unbound from the underlying physical struct &device. Best to use
265 * &drm_device managed resources with drmm_add_action(), drmm_kmalloc() and
266 * related functions.
267 *
268 * devres managed resources like devm_kmalloc() can only be used for resources
269 * directly related to the underlying hardware device, and only used in code
270 * paths fully protected by drm_dev_enter() and drm_dev_exit().
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000271 *
David Brazdil0f672f62019-12-10 10:32:29 +0000272 * Display driver example
273 * ~~~~~~~~~~~~~~~~~~~~~~
274 *
275 * The following example shows a typical structure of a DRM display driver.
276 * The example focus on the probe() function and the other functions that is
Olivier Deprez157378f2022-04-04 15:47:50 +0200277 * almost always present and serves as a demonstration of devm_drm_dev_alloc().
David Brazdil0f672f62019-12-10 10:32:29 +0000278 *
279 * .. code-block:: c
280 *
281 * struct driver_device {
282 * struct drm_device drm;
283 * void *userspace_facing;
284 * struct clk *pclk;
285 * };
286 *
David Brazdil0f672f62019-12-10 10:32:29 +0000287 * static struct drm_driver driver_drm_driver = {
288 * [...]
David Brazdil0f672f62019-12-10 10:32:29 +0000289 * };
290 *
291 * static int driver_probe(struct platform_device *pdev)
292 * {
293 * struct driver_device *priv;
294 * struct drm_device *drm;
295 * int ret;
296 *
Olivier Deprez157378f2022-04-04 15:47:50 +0200297 * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver,
298 * struct driver_device, drm);
299 * if (IS_ERR(priv))
300 * return PTR_ERR(priv);
David Brazdil0f672f62019-12-10 10:32:29 +0000301 * drm = &priv->drm;
302 *
Olivier Deprez157378f2022-04-04 15:47:50 +0200303 * ret = drmm_mode_config_init(drm);
304 * if (ret)
David Brazdil0f672f62019-12-10 10:32:29 +0000305 * return ret;
David Brazdil0f672f62019-12-10 10:32:29 +0000306 *
Olivier Deprez157378f2022-04-04 15:47:50 +0200307 * priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL);
David Brazdil0f672f62019-12-10 10:32:29 +0000308 * if (!priv->userspace_facing)
309 * return -ENOMEM;
310 *
311 * priv->pclk = devm_clk_get(dev, "PCLK");
312 * if (IS_ERR(priv->pclk))
313 * return PTR_ERR(priv->pclk);
314 *
315 * // Further setup, display pipeline etc
316 *
317 * platform_set_drvdata(pdev, drm);
318 *
319 * drm_mode_config_reset(drm);
320 *
321 * ret = drm_dev_register(drm);
322 * if (ret)
323 * return ret;
324 *
325 * drm_fbdev_generic_setup(drm, 32);
326 *
327 * return 0;
328 * }
329 *
330 * // This function is called before the devm_ resources are released
331 * static int driver_remove(struct platform_device *pdev)
332 * {
333 * struct drm_device *drm = platform_get_drvdata(pdev);
334 *
335 * drm_dev_unregister(drm);
336 * drm_atomic_helper_shutdown(drm)
337 *
338 * return 0;
339 * }
340 *
341 * // This function is called on kernel restart and shutdown
342 * static void driver_shutdown(struct platform_device *pdev)
343 * {
344 * drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
345 * }
346 *
347 * static int __maybe_unused driver_pm_suspend(struct device *dev)
348 * {
349 * return drm_mode_config_helper_suspend(dev_get_drvdata(dev));
350 * }
351 *
352 * static int __maybe_unused driver_pm_resume(struct device *dev)
353 * {
354 * drm_mode_config_helper_resume(dev_get_drvdata(dev));
355 *
356 * return 0;
357 * }
358 *
359 * static const struct dev_pm_ops driver_pm_ops = {
360 * SET_SYSTEM_SLEEP_PM_OPS(driver_pm_suspend, driver_pm_resume)
361 * };
362 *
363 * static struct platform_driver driver_driver = {
364 * .driver = {
365 * [...]
366 * .pm = &driver_pm_ops,
367 * },
368 * .probe = driver_probe,
369 * .remove = driver_remove,
370 * .shutdown = driver_shutdown,
371 * };
372 * module_platform_driver(driver_driver);
373 *
374 * Drivers that want to support device unplugging (USB, DT overlay unload) should
375 * use drm_dev_unplug() instead of drm_dev_unregister(). The driver must protect
376 * regions that is accessing device resources to prevent use after they're
377 * released. This is done using drm_dev_enter() and drm_dev_exit(). There is one
378 * shortcoming however, drm_dev_unplug() marks the drm_device as unplugged before
379 * drm_atomic_helper_shutdown() is called. This means that if the disable code
380 * paths are protected, they will not run on regular driver module unload,
381 * possibily leaving the hardware enabled.
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000382 */
383
384/**
385 * drm_put_dev - Unregister and release a DRM device
386 * @dev: DRM device
387 *
388 * Called at module unload time or when a PCI device is unplugged.
389 *
390 * Cleans up all DRM device, calling drm_lastclose().
391 *
392 * Note: Use of this function is deprecated. It will eventually go away
393 * completely. Please use drm_dev_unregister() and drm_dev_put() explicitly
394 * instead to make sure that the device isn't userspace accessible any more
395 * while teardown is in progress, ensuring that userspace can't access an
396 * inconsistent state.
397 */
398void drm_put_dev(struct drm_device *dev)
399{
400 DRM_DEBUG("\n");
401
402 if (!dev) {
403 DRM_ERROR("cleanup called no dev\n");
404 return;
405 }
406
407 drm_dev_unregister(dev);
408 drm_dev_put(dev);
409}
410EXPORT_SYMBOL(drm_put_dev);
411
412/**
413 * drm_dev_enter - Enter device critical section
414 * @dev: DRM device
415 * @idx: Pointer to index that will be passed to the matching drm_dev_exit()
416 *
417 * This function marks and protects the beginning of a section that should not
418 * be entered after the device has been unplugged. The section end is marked
419 * with drm_dev_exit(). Calls to this function can be nested.
420 *
421 * Returns:
422 * True if it is OK to enter the section, false otherwise.
423 */
424bool drm_dev_enter(struct drm_device *dev, int *idx)
425{
426 *idx = srcu_read_lock(&drm_unplug_srcu);
427
428 if (dev->unplugged) {
429 srcu_read_unlock(&drm_unplug_srcu, *idx);
430 return false;
431 }
432
433 return true;
434}
435EXPORT_SYMBOL(drm_dev_enter);
436
437/**
438 * drm_dev_exit - Exit device critical section
439 * @idx: index returned from drm_dev_enter()
440 *
441 * This function marks the end of a section that should not be entered after
442 * the device has been unplugged.
443 */
444void drm_dev_exit(int idx)
445{
446 srcu_read_unlock(&drm_unplug_srcu, idx);
447}
448EXPORT_SYMBOL(drm_dev_exit);
449
450/**
451 * drm_dev_unplug - unplug a DRM device
452 * @dev: DRM device
453 *
454 * This unplugs a hotpluggable DRM device, which makes it inaccessible to
455 * userspace operations. Entry-points can use drm_dev_enter() and
456 * drm_dev_exit() to protect device resources in a race free manner. This
457 * essentially unregisters the device like drm_dev_unregister(), but can be
458 * called while there are still open users of @dev.
459 */
460void drm_dev_unplug(struct drm_device *dev)
461{
462 /*
463 * After synchronizing any critical read section is guaranteed to see
464 * the new value of ->unplugged, and any critical section which might
465 * still have seen the old value of ->unplugged is guaranteed to have
466 * finished.
467 */
468 dev->unplugged = true;
469 synchronize_srcu(&drm_unplug_srcu);
470
471 drm_dev_unregister(dev);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000472}
473EXPORT_SYMBOL(drm_dev_unplug);
474
475/*
476 * DRM internal mount
477 * We want to be able to allocate our own "struct address_space" to control
478 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
479 * stand-alone address_space objects, so we need an underlying inode. As there
480 * is no way to allocate an independent inode easily, we need a fake internal
481 * VFS mount-point.
482 *
483 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
484 * frees it again. You are allowed to use iget() and iput() to get references to
485 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
486 * drm_fs_inode_free() call (which does not have to be the last iput()).
487 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
488 * between multiple inode-users. You could, technically, call
489 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
490 * iput(), but this way you'd end up with a new vfsmount for each inode.
491 */
492
493static int drm_fs_cnt;
494static struct vfsmount *drm_fs_mnt;
495
David Brazdil0f672f62019-12-10 10:32:29 +0000496static int drm_fs_init_fs_context(struct fs_context *fc)
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000497{
David Brazdil0f672f62019-12-10 10:32:29 +0000498 return init_pseudo(fc, 0x010203ff) ? 0 : -ENOMEM;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000499}
500
501static struct file_system_type drm_fs_type = {
502 .name = "drm",
503 .owner = THIS_MODULE,
David Brazdil0f672f62019-12-10 10:32:29 +0000504 .init_fs_context = drm_fs_init_fs_context,
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000505 .kill_sb = kill_anon_super,
506};
507
508static struct inode *drm_fs_inode_new(void)
509{
510 struct inode *inode;
511 int r;
512
513 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
514 if (r < 0) {
515 DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
516 return ERR_PTR(r);
517 }
518
519 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
520 if (IS_ERR(inode))
521 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
522
523 return inode;
524}
525
526static void drm_fs_inode_free(struct inode *inode)
527{
528 if (inode) {
529 iput(inode);
530 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
531 }
532}
533
534/**
David Brazdil0f672f62019-12-10 10:32:29 +0000535 * DOC: component helper usage recommendations
536 *
537 * DRM drivers that drive hardware where a logical device consists of a pile of
538 * independent hardware blocks are recommended to use the :ref:`component helper
539 * library<component>`. For consistency and better options for code reuse the
540 * following guidelines apply:
541 *
542 * - The entire device initialization procedure should be run from the
Olivier Deprez157378f2022-04-04 15:47:50 +0200543 * &component_master_ops.master_bind callback, starting with
544 * devm_drm_dev_alloc(), then binding all components with
545 * component_bind_all() and finishing with drm_dev_register().
David Brazdil0f672f62019-12-10 10:32:29 +0000546 *
547 * - The opaque pointer passed to all components through component_bind_all()
548 * should point at &struct drm_device of the device instance, not some driver
549 * specific private structure.
550 *
551 * - The component helper fills the niche where further standardization of
552 * interfaces is not practical. When there already is, or will be, a
553 * standardized interface like &drm_bridge or &drm_panel, providing its own
554 * functions to find such components at driver load time, like
555 * drm_of_find_panel_or_bridge(), then the component helper should not be
556 * used.
557 */
558
Olivier Deprez157378f2022-04-04 15:47:50 +0200559static void drm_dev_init_release(struct drm_device *dev, void *res)
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000560{
Olivier Deprez157378f2022-04-04 15:47:50 +0200561 drm_legacy_ctxbitmap_cleanup(dev);
562 drm_legacy_remove_map_hash(dev);
563 drm_fs_inode_free(dev->anon_inode);
564
565 put_device(dev->dev);
566 /* Prevent use-after-free in drm_managed_release when debugging is
567 * enabled. Slightly awkward, but can't really be helped. */
568 dev->dev = NULL;
569 mutex_destroy(&dev->master_mutex);
570 mutex_destroy(&dev->clientlist_mutex);
571 mutex_destroy(&dev->filelist_mutex);
572 mutex_destroy(&dev->struct_mutex);
573 drm_legacy_destroy_members(dev);
574}
575
576static int drm_dev_init(struct drm_device *dev,
577 struct drm_driver *driver,
578 struct device *parent)
579{
580 struct inode *inode;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000581 int ret;
582
583 if (!drm_core_init_complete) {
584 DRM_ERROR("DRM core is not initialized\n");
585 return -ENODEV;
586 }
587
Olivier Deprez157378f2022-04-04 15:47:50 +0200588 if (WARN_ON(!parent))
589 return -EINVAL;
David Brazdil0f672f62019-12-10 10:32:29 +0000590
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000591 kref_init(&dev->ref);
David Brazdil0f672f62019-12-10 10:32:29 +0000592 dev->dev = get_device(parent);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000593 dev->driver = driver;
594
Olivier Deprez157378f2022-04-04 15:47:50 +0200595 INIT_LIST_HEAD(&dev->managed.resources);
596 spin_lock_init(&dev->managed.lock);
597
David Brazdil0f672f62019-12-10 10:32:29 +0000598 /* no per-device feature limits by default */
599 dev->driver_features = ~0u;
600
601 drm_legacy_init_members(dev);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000602 INIT_LIST_HEAD(&dev->filelist);
603 INIT_LIST_HEAD(&dev->filelist_internal);
604 INIT_LIST_HEAD(&dev->clientlist);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000605 INIT_LIST_HEAD(&dev->vblank_event_list);
606
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000607 spin_lock_init(&dev->event_lock);
608 mutex_init(&dev->struct_mutex);
609 mutex_init(&dev->filelist_mutex);
610 mutex_init(&dev->clientlist_mutex);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000611 mutex_init(&dev->master_mutex);
612
Olivier Deprez157378f2022-04-04 15:47:50 +0200613 ret = drmm_add_action(dev, drm_dev_init_release, NULL);
614 if (ret)
615 return ret;
616
617 inode = drm_fs_inode_new();
618 if (IS_ERR(inode)) {
619 ret = PTR_ERR(inode);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000620 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
Olivier Deprez157378f2022-04-04 15:47:50 +0200621 goto err;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000622 }
623
Olivier Deprez157378f2022-04-04 15:47:50 +0200624 dev->anon_inode = inode;
625
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000626 if (drm_core_check_feature(dev, DRIVER_RENDER)) {
627 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
628 if (ret)
Olivier Deprez157378f2022-04-04 15:47:50 +0200629 goto err;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000630 }
631
632 ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY);
633 if (ret)
Olivier Deprez157378f2022-04-04 15:47:50 +0200634 goto err;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000635
David Brazdil0f672f62019-12-10 10:32:29 +0000636 ret = drm_legacy_create_map_hash(dev);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000637 if (ret)
Olivier Deprez157378f2022-04-04 15:47:50 +0200638 goto err;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000639
640 drm_legacy_ctxbitmap_init(dev);
641
642 if (drm_core_check_feature(dev, DRIVER_GEM)) {
643 ret = drm_gem_init(dev);
644 if (ret) {
645 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
Olivier Deprez157378f2022-04-04 15:47:50 +0200646 goto err;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000647 }
648 }
649
David Brazdil0f672f62019-12-10 10:32:29 +0000650 ret = drm_dev_set_unique(dev, dev_name(parent));
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000651 if (ret)
Olivier Deprez157378f2022-04-04 15:47:50 +0200652 goto err;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000653
654 return 0;
655
Olivier Deprez157378f2022-04-04 15:47:50 +0200656err:
657 drm_managed_release(dev);
658
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000659 return ret;
660}
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000661
David Brazdil0f672f62019-12-10 10:32:29 +0000662static void devm_drm_dev_init_release(void *data)
663{
664 drm_dev_put(data);
665}
666
Olivier Deprez157378f2022-04-04 15:47:50 +0200667static int devm_drm_dev_init(struct device *parent,
668 struct drm_device *dev,
669 struct drm_driver *driver)
David Brazdil0f672f62019-12-10 10:32:29 +0000670{
671 int ret;
672
David Brazdil0f672f62019-12-10 10:32:29 +0000673 ret = drm_dev_init(dev, driver, parent);
674 if (ret)
675 return ret;
676
677 ret = devm_add_action(parent, devm_drm_dev_init_release, dev);
678 if (ret)
679 devm_drm_dev_init_release(dev);
680
681 return ret;
682}
David Brazdil0f672f62019-12-10 10:32:29 +0000683
Olivier Deprez157378f2022-04-04 15:47:50 +0200684void *__devm_drm_dev_alloc(struct device *parent, struct drm_driver *driver,
685 size_t size, size_t offset)
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000686{
Olivier Deprez157378f2022-04-04 15:47:50 +0200687 void *container;
688 struct drm_device *drm;
689 int ret;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000690
Olivier Deprez157378f2022-04-04 15:47:50 +0200691 container = kzalloc(size, GFP_KERNEL);
692 if (!container)
693 return ERR_PTR(-ENOMEM);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000694
Olivier Deprez157378f2022-04-04 15:47:50 +0200695 drm = container + offset;
696 ret = devm_drm_dev_init(parent, drm, driver);
697 if (ret) {
698 kfree(container);
699 return ERR_PTR(ret);
700 }
701 drmm_add_final_kfree(drm, container);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000702
Olivier Deprez157378f2022-04-04 15:47:50 +0200703 return container;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000704}
Olivier Deprez157378f2022-04-04 15:47:50 +0200705EXPORT_SYMBOL(__devm_drm_dev_alloc);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000706
707/**
708 * drm_dev_alloc - Allocate new DRM device
709 * @driver: DRM driver to allocate device for
710 * @parent: Parent device object
711 *
Olivier Deprez157378f2022-04-04 15:47:50 +0200712 * This is the deprecated version of devm_drm_dev_alloc(), which does not support
713 * subclassing through embedding the struct &drm_device in a driver private
714 * structure, and which does not support automatic cleanup through devres.
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000715 *
716 * RETURNS:
717 * Pointer to new DRM device, or ERR_PTR on failure.
718 */
719struct drm_device *drm_dev_alloc(struct drm_driver *driver,
720 struct device *parent)
721{
722 struct drm_device *dev;
723 int ret;
724
725 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
726 if (!dev)
727 return ERR_PTR(-ENOMEM);
728
729 ret = drm_dev_init(dev, driver, parent);
730 if (ret) {
731 kfree(dev);
732 return ERR_PTR(ret);
733 }
734
Olivier Deprez157378f2022-04-04 15:47:50 +0200735 drmm_add_final_kfree(dev, dev);
736
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000737 return dev;
738}
739EXPORT_SYMBOL(drm_dev_alloc);
740
741static void drm_dev_release(struct kref *ref)
742{
743 struct drm_device *dev = container_of(ref, struct drm_device, ref);
744
Olivier Deprez157378f2022-04-04 15:47:50 +0200745 if (dev->driver->release)
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000746 dev->driver->release(dev);
Olivier Deprez157378f2022-04-04 15:47:50 +0200747
748 drm_managed_release(dev);
749
750 kfree(dev->managed.final_kfree);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000751}
752
753/**
754 * drm_dev_get - Take reference of a DRM device
755 * @dev: device to take reference of or NULL
756 *
757 * This increases the ref-count of @dev by one. You *must* already own a
758 * reference when calling this. Use drm_dev_put() to drop this reference
759 * again.
760 *
761 * This function never fails. However, this function does not provide *any*
762 * guarantee whether the device is alive or running. It only provides a
763 * reference to the object and the memory associated with it.
764 */
765void drm_dev_get(struct drm_device *dev)
766{
767 if (dev)
768 kref_get(&dev->ref);
769}
770EXPORT_SYMBOL(drm_dev_get);
771
772/**
773 * drm_dev_put - Drop reference of a DRM device
774 * @dev: device to drop reference of or NULL
775 *
776 * This decreases the ref-count of @dev by one. The device is destroyed if the
777 * ref-count drops to zero.
778 */
779void drm_dev_put(struct drm_device *dev)
780{
781 if (dev)
782 kref_put(&dev->ref, drm_dev_release);
783}
784EXPORT_SYMBOL(drm_dev_put);
785
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000786static int create_compat_control_link(struct drm_device *dev)
787{
788 struct drm_minor *minor;
789 char *name;
790 int ret;
791
792 if (!drm_core_check_feature(dev, DRIVER_MODESET))
793 return 0;
794
795 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
796 if (!minor)
797 return 0;
798
799 /*
800 * Some existing userspace out there uses the existing of the controlD*
801 * sysfs files to figure out whether it's a modeset driver. It only does
802 * readdir, hence a symlink is sufficient (and the least confusing
803 * option). Otherwise controlD* is entirely unused.
804 *
805 * Old controlD chardev have been allocated in the range
806 * 64-127.
807 */
808 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
809 if (!name)
810 return -ENOMEM;
811
812 ret = sysfs_create_link(minor->kdev->kobj.parent,
813 &minor->kdev->kobj,
814 name);
815
816 kfree(name);
817
818 return ret;
819}
820
821static void remove_compat_control_link(struct drm_device *dev)
822{
823 struct drm_minor *minor;
824 char *name;
825
826 if (!drm_core_check_feature(dev, DRIVER_MODESET))
827 return;
828
829 minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
830 if (!minor)
831 return;
832
833 name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
834 if (!name)
835 return;
836
837 sysfs_remove_link(minor->kdev->kobj.parent, name);
838
839 kfree(name);
840}
841
842/**
843 * drm_dev_register - Register DRM device
844 * @dev: Device to register
845 * @flags: Flags passed to the driver's .load() function
846 *
847 * Register the DRM device @dev with the system, advertise device to user-space
David Brazdil0f672f62019-12-10 10:32:29 +0000848 * and start normal device operation. @dev must be initialized via drm_dev_init()
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000849 * previously.
850 *
851 * Never call this twice on any device!
852 *
853 * NOTE: To ensure backward compatibility with existing drivers method this
854 * function calls the &drm_driver.load method after registering the device
855 * nodes, creating race conditions. Usage of the &drm_driver.load methods is
856 * therefore deprecated, drivers must perform all initialization before calling
857 * drm_dev_register().
858 *
859 * RETURNS:
860 * 0 on success, negative error code on failure.
861 */
862int drm_dev_register(struct drm_device *dev, unsigned long flags)
863{
864 struct drm_driver *driver = dev->driver;
865 int ret;
866
Olivier Deprez157378f2022-04-04 15:47:50 +0200867 if (!driver->load)
868 drm_mode_config_validate(dev);
869
870 WARN_ON(!dev->managed.final_kfree);
871
872 if (drm_dev_needs_global_mutex(dev))
873 mutex_lock(&drm_global_mutex);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000874
875 ret = drm_minor_register(dev, DRM_MINOR_RENDER);
876 if (ret)
877 goto err_minors;
878
879 ret = drm_minor_register(dev, DRM_MINOR_PRIMARY);
880 if (ret)
881 goto err_minors;
882
883 ret = create_compat_control_link(dev);
884 if (ret)
885 goto err_minors;
886
887 dev->registered = true;
888
889 if (dev->driver->load) {
890 ret = dev->driver->load(dev, flags);
891 if (ret)
892 goto err_minors;
893 }
894
895 if (drm_core_check_feature(dev, DRIVER_MODESET))
896 drm_modeset_register_all(dev);
897
898 ret = 0;
899
900 DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
901 driver->name, driver->major, driver->minor,
902 driver->patchlevel, driver->date,
903 dev->dev ? dev_name(dev->dev) : "virtual device",
904 dev->primary->index);
905
906 goto out_unlock;
907
908err_minors:
909 remove_compat_control_link(dev);
910 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
911 drm_minor_unregister(dev, DRM_MINOR_RENDER);
912out_unlock:
Olivier Deprez157378f2022-04-04 15:47:50 +0200913 if (drm_dev_needs_global_mutex(dev))
914 mutex_unlock(&drm_global_mutex);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000915 return ret;
916}
917EXPORT_SYMBOL(drm_dev_register);
918
919/**
920 * drm_dev_unregister - Unregister DRM device
921 * @dev: Device to unregister
922 *
923 * Unregister the DRM device from the system. This does the reverse of
924 * drm_dev_register() but does not deallocate the device. The caller must call
925 * drm_dev_put() to drop their final reference.
926 *
927 * A special form of unregistering for hotpluggable devices is drm_dev_unplug(),
928 * which can be called while there are still open users of @dev.
929 *
930 * This should be called first in the device teardown code to make sure
931 * userspace can't access the device instance any more.
932 */
933void drm_dev_unregister(struct drm_device *dev)
934{
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000935 if (drm_core_check_feature(dev, DRIVER_LEGACY))
936 drm_lastclose(dev);
937
938 dev->registered = false;
939
940 drm_client_dev_unregister(dev);
941
942 if (drm_core_check_feature(dev, DRIVER_MODESET))
943 drm_modeset_unregister_all(dev);
944
945 if (dev->driver->unload)
946 dev->driver->unload(dev);
947
948 if (dev->agp)
949 drm_pci_agp_destroy(dev);
950
David Brazdil0f672f62019-12-10 10:32:29 +0000951 drm_legacy_rmmaps(dev);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000952
953 remove_compat_control_link(dev);
954 drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
955 drm_minor_unregister(dev, DRM_MINOR_RENDER);
956}
957EXPORT_SYMBOL(drm_dev_unregister);
958
959/**
960 * drm_dev_set_unique - Set the unique name of a DRM device
961 * @dev: device of which to set the unique name
962 * @name: unique name
963 *
David Brazdil0f672f62019-12-10 10:32:29 +0000964 * Sets the unique name of a DRM device using the specified string. This is
965 * already done by drm_dev_init(), drivers should only override the default
966 * unique name for backwards compatibility reasons.
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000967 *
968 * Return: 0 on success or a negative error code on failure.
969 */
970int drm_dev_set_unique(struct drm_device *dev, const char *name)
971{
Olivier Deprez157378f2022-04-04 15:47:50 +0200972 drmm_kfree(dev, dev->unique);
973 dev->unique = drmm_kstrdup(dev, name, GFP_KERNEL);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +0000974
975 return dev->unique ? 0 : -ENOMEM;
976}
977EXPORT_SYMBOL(drm_dev_set_unique);
978
979/*
980 * DRM Core
981 * The DRM core module initializes all global DRM objects and makes them
982 * available to drivers. Once setup, drivers can probe their respective
983 * devices.
984 * Currently, core management includes:
985 * - The "DRM-Global" key/value database
986 * - Global ID management for connectors
987 * - DRM major number allocation
988 * - DRM minor management
989 * - DRM sysfs class
990 * - DRM debugfs root
991 *
992 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
993 * interface registered on a DRM device, you can request minor numbers from DRM
994 * core. DRM core takes care of major-number management and char-dev
995 * registration. A stub ->open() callback forwards any open() requests to the
996 * registered minor.
997 */
998
999static int drm_stub_open(struct inode *inode, struct file *filp)
1000{
1001 const struct file_operations *new_fops;
1002 struct drm_minor *minor;
1003 int err;
1004
1005 DRM_DEBUG("\n");
1006
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001007 minor = drm_minor_acquire(iminor(inode));
Olivier Deprez157378f2022-04-04 15:47:50 +02001008 if (IS_ERR(minor))
1009 return PTR_ERR(minor);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001010
1011 new_fops = fops_get(minor->dev->driver->fops);
1012 if (!new_fops) {
1013 err = -ENODEV;
Olivier Deprez157378f2022-04-04 15:47:50 +02001014 goto out;
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001015 }
1016
1017 replace_fops(filp, new_fops);
1018 if (filp->f_op->open)
1019 err = filp->f_op->open(inode, filp);
1020 else
1021 err = 0;
1022
Olivier Deprez157378f2022-04-04 15:47:50 +02001023out:
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001024 drm_minor_release(minor);
Olivier Deprez157378f2022-04-04 15:47:50 +02001025
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001026 return err;
1027}
1028
1029static const struct file_operations drm_stub_fops = {
1030 .owner = THIS_MODULE,
1031 .open = drm_stub_open,
1032 .llseek = noop_llseek,
1033};
1034
1035static void drm_core_exit(void)
1036{
1037 unregister_chrdev(DRM_MAJOR, "drm");
1038 debugfs_remove(drm_debugfs_root);
1039 drm_sysfs_destroy();
1040 idr_destroy(&drm_minors_idr);
1041 drm_connector_ida_destroy();
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001042}
1043
1044static int __init drm_core_init(void)
1045{
1046 int ret;
1047
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001048 drm_connector_ida_init();
1049 idr_init(&drm_minors_idr);
1050
1051 ret = drm_sysfs_init();
1052 if (ret < 0) {
1053 DRM_ERROR("Cannot create DRM class: %d\n", ret);
1054 goto error;
1055 }
1056
1057 drm_debugfs_root = debugfs_create_dir("dri", NULL);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001058
1059 ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops);
1060 if (ret < 0)
1061 goto error;
1062
1063 drm_core_init_complete = true;
1064
1065 DRM_DEBUG("Initialized\n");
1066 return 0;
1067
1068error:
1069 drm_core_exit();
1070 return ret;
1071}
1072
1073module_init(drm_core_init);
1074module_exit(drm_core_exit);