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 | #include "drm_legacy.h" |
52 | |
53 | MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl" ); |
54 | MODULE_DESCRIPTION("DRM shared core routines" ); |
55 | MODULE_LICENSE("GPL and additional rights" ); |
56 | |
57 | static DEFINE_SPINLOCK(drm_minor_lock); |
58 | static struct idr drm_minors_idr; |
59 | |
60 | /* |
61 | * If the drm core fails to init for whatever reason, |
62 | * we should prevent any drivers from registering with it. |
63 | * It's best to check this at drm_dev_init(), as some drivers |
64 | * prefer to embed struct drm_device into their own device |
65 | * structure and call drm_dev_init() themselves. |
66 | */ |
67 | static bool drm_core_init_complete; |
68 | |
69 | static struct dentry *drm_debugfs_root; |
70 | |
71 | DEFINE_STATIC_SRCU(drm_unplug_srcu); |
72 | |
73 | /* |
74 | * DRM Minors |
75 | * A DRM device can provide several char-dev interfaces on the DRM-Major. Each |
76 | * of them is represented by a drm_minor object. Depending on the capabilities |
77 | * of the device-driver, different interfaces are registered. |
78 | * |
79 | * Minors can be accessed via dev->$minor_name. This pointer is either |
80 | * NULL or a valid drm_minor pointer and stays valid as long as the device is |
81 | * valid. This means, DRM minors have the same life-time as the underlying |
82 | * device. However, this doesn't mean that the minor is active. Minors are |
83 | * registered and unregistered dynamically according to device-state. |
84 | */ |
85 | |
86 | static struct drm_minor **drm_minor_get_slot(struct drm_device *dev, |
87 | enum drm_minor_type type) |
88 | { |
89 | switch (type) { |
90 | case DRM_MINOR_PRIMARY: |
91 | return &dev->primary; |
92 | case DRM_MINOR_RENDER: |
93 | return &dev->render; |
94 | case DRM_MINOR_ACCEL: |
95 | return &dev->accel; |
96 | default: |
97 | BUG(); |
98 | } |
99 | } |
100 | |
101 | static void drm_minor_alloc_release(struct drm_device *dev, void *data) |
102 | { |
103 | struct drm_minor *minor = data; |
104 | unsigned long flags; |
105 | |
106 | WARN_ON(dev != minor->dev); |
107 | |
108 | put_device(dev: minor->kdev); |
109 | |
110 | if (minor->type == DRM_MINOR_ACCEL) { |
111 | accel_minor_remove(index: minor->index); |
112 | } else { |
113 | spin_lock_irqsave(&drm_minor_lock, flags); |
114 | idr_remove(&drm_minors_idr, id: minor->index); |
115 | spin_unlock_irqrestore(lock: &drm_minor_lock, flags); |
116 | } |
117 | } |
118 | |
119 | static int drm_minor_alloc(struct drm_device *dev, enum drm_minor_type type) |
120 | { |
121 | struct drm_minor *minor; |
122 | unsigned long flags; |
123 | int r; |
124 | |
125 | minor = drmm_kzalloc(dev, size: sizeof(*minor), GFP_KERNEL); |
126 | if (!minor) |
127 | return -ENOMEM; |
128 | |
129 | minor->type = type; |
130 | minor->dev = dev; |
131 | |
132 | idr_preload(GFP_KERNEL); |
133 | if (type == DRM_MINOR_ACCEL) { |
134 | r = accel_minor_alloc(); |
135 | } else { |
136 | spin_lock_irqsave(&drm_minor_lock, flags); |
137 | r = idr_alloc(&drm_minors_idr, |
138 | NULL, |
139 | start: 64 * type, |
140 | end: 64 * (type + 1), |
141 | GFP_NOWAIT); |
142 | spin_unlock_irqrestore(lock: &drm_minor_lock, flags); |
143 | } |
144 | idr_preload_end(); |
145 | |
146 | if (r < 0) |
147 | return r; |
148 | |
149 | minor->index = r; |
150 | |
151 | r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor); |
152 | if (r) |
153 | return r; |
154 | |
155 | minor->kdev = drm_sysfs_minor_alloc(minor); |
156 | if (IS_ERR(ptr: minor->kdev)) |
157 | return PTR_ERR(ptr: minor->kdev); |
158 | |
159 | *drm_minor_get_slot(dev, type) = minor; |
160 | return 0; |
161 | } |
162 | |
163 | static int drm_minor_register(struct drm_device *dev, enum drm_minor_type type) |
164 | { |
165 | struct drm_minor *minor; |
166 | unsigned long flags; |
167 | int ret; |
168 | |
169 | DRM_DEBUG("\n" ); |
170 | |
171 | minor = *drm_minor_get_slot(dev, type); |
172 | if (!minor) |
173 | return 0; |
174 | |
175 | if (minor->type != DRM_MINOR_ACCEL) { |
176 | ret = drm_debugfs_register(minor, minor_id: minor->index, |
177 | root: drm_debugfs_root); |
178 | if (ret) { |
179 | DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n" ); |
180 | goto err_debugfs; |
181 | } |
182 | } |
183 | |
184 | ret = device_add(dev: minor->kdev); |
185 | if (ret) |
186 | goto err_debugfs; |
187 | |
188 | /* replace NULL with @minor so lookups will succeed from now on */ |
189 | if (minor->type == DRM_MINOR_ACCEL) { |
190 | accel_minor_replace(minor, index: minor->index); |
191 | } else { |
192 | spin_lock_irqsave(&drm_minor_lock, flags); |
193 | idr_replace(&drm_minors_idr, minor, id: minor->index); |
194 | spin_unlock_irqrestore(lock: &drm_minor_lock, flags); |
195 | } |
196 | |
197 | DRM_DEBUG("new minor registered %d\n" , minor->index); |
198 | return 0; |
199 | |
200 | err_debugfs: |
201 | drm_debugfs_unregister(minor); |
202 | return ret; |
203 | } |
204 | |
205 | static void drm_minor_unregister(struct drm_device *dev, enum drm_minor_type type) |
206 | { |
207 | struct drm_minor *minor; |
208 | unsigned long flags; |
209 | |
210 | minor = *drm_minor_get_slot(dev, type); |
211 | if (!minor || !device_is_registered(dev: minor->kdev)) |
212 | return; |
213 | |
214 | /* replace @minor with NULL so lookups will fail from now on */ |
215 | if (minor->type == DRM_MINOR_ACCEL) { |
216 | accel_minor_replace(NULL, index: minor->index); |
217 | } else { |
218 | spin_lock_irqsave(&drm_minor_lock, flags); |
219 | idr_replace(&drm_minors_idr, NULL, id: minor->index); |
220 | spin_unlock_irqrestore(lock: &drm_minor_lock, flags); |
221 | } |
222 | |
223 | device_del(dev: minor->kdev); |
224 | dev_set_drvdata(dev: minor->kdev, NULL); /* safety belt */ |
225 | drm_debugfs_unregister(minor); |
226 | } |
227 | |
228 | /* |
229 | * Looks up the given minor-ID and returns the respective DRM-minor object. The |
230 | * refence-count of the underlying device is increased so you must release this |
231 | * object with drm_minor_release(). |
232 | * |
233 | * As long as you hold this minor, it is guaranteed that the object and the |
234 | * minor->dev pointer will stay valid! However, the device may get unplugged and |
235 | * unregistered while you hold the minor. |
236 | */ |
237 | struct drm_minor *drm_minor_acquire(unsigned int minor_id) |
238 | { |
239 | struct drm_minor *minor; |
240 | unsigned long flags; |
241 | |
242 | spin_lock_irqsave(&drm_minor_lock, flags); |
243 | minor = idr_find(&drm_minors_idr, id: minor_id); |
244 | if (minor) |
245 | drm_dev_get(dev: minor->dev); |
246 | spin_unlock_irqrestore(lock: &drm_minor_lock, flags); |
247 | |
248 | if (!minor) { |
249 | return ERR_PTR(error: -ENODEV); |
250 | } else if (drm_dev_is_unplugged(dev: minor->dev)) { |
251 | drm_dev_put(dev: minor->dev); |
252 | return ERR_PTR(error: -ENODEV); |
253 | } |
254 | |
255 | return minor; |
256 | } |
257 | |
258 | void drm_minor_release(struct drm_minor *minor) |
259 | { |
260 | drm_dev_put(dev: minor->dev); |
261 | } |
262 | |
263 | /** |
264 | * DOC: driver instance overview |
265 | * |
266 | * A device instance for a drm driver is represented by &struct drm_device. This |
267 | * is allocated and initialized with devm_drm_dev_alloc(), usually from |
268 | * bus-specific ->probe() callbacks implemented by the driver. The driver then |
269 | * needs to initialize all the various subsystems for the drm device like memory |
270 | * management, vblank handling, modesetting support and initial output |
271 | * configuration plus obviously initialize all the corresponding hardware bits. |
272 | * Finally when everything is up and running and ready for userspace the device |
273 | * instance can be published using drm_dev_register(). |
274 | * |
275 | * There is also deprecated support for initializing device instances using |
276 | * bus-specific helpers and the &drm_driver.load callback. But due to |
277 | * backwards-compatibility needs the device instance have to be published too |
278 | * early, which requires unpretty global locking to make safe and is therefore |
279 | * only support for existing drivers not yet converted to the new scheme. |
280 | * |
281 | * When cleaning up a device instance everything needs to be done in reverse: |
282 | * First unpublish the device instance with drm_dev_unregister(). Then clean up |
283 | * any other resources allocated at device initialization and drop the driver's |
284 | * reference to &drm_device using drm_dev_put(). |
285 | * |
286 | * Note that any allocation or resource which is visible to userspace must be |
287 | * released only when the final drm_dev_put() is called, and not when the |
288 | * driver is unbound from the underlying physical struct &device. Best to use |
289 | * &drm_device managed resources with drmm_add_action(), drmm_kmalloc() and |
290 | * related functions. |
291 | * |
292 | * devres managed resources like devm_kmalloc() can only be used for resources |
293 | * directly related to the underlying hardware device, and only used in code |
294 | * paths fully protected by drm_dev_enter() and drm_dev_exit(). |
295 | * |
296 | * Display driver example |
297 | * ~~~~~~~~~~~~~~~~~~~~~~ |
298 | * |
299 | * The following example shows a typical structure of a DRM display driver. |
300 | * The example focus on the probe() function and the other functions that is |
301 | * almost always present and serves as a demonstration of devm_drm_dev_alloc(). |
302 | * |
303 | * .. code-block:: c |
304 | * |
305 | * struct driver_device { |
306 | * struct drm_device drm; |
307 | * void *userspace_facing; |
308 | * struct clk *pclk; |
309 | * }; |
310 | * |
311 | * static const struct drm_driver driver_drm_driver = { |
312 | * [...] |
313 | * }; |
314 | * |
315 | * static int driver_probe(struct platform_device *pdev) |
316 | * { |
317 | * struct driver_device *priv; |
318 | * struct drm_device *drm; |
319 | * int ret; |
320 | * |
321 | * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver, |
322 | * struct driver_device, drm); |
323 | * if (IS_ERR(priv)) |
324 | * return PTR_ERR(priv); |
325 | * drm = &priv->drm; |
326 | * |
327 | * ret = drmm_mode_config_init(drm); |
328 | * if (ret) |
329 | * return ret; |
330 | * |
331 | * priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL); |
332 | * if (!priv->userspace_facing) |
333 | * return -ENOMEM; |
334 | * |
335 | * priv->pclk = devm_clk_get(dev, "PCLK"); |
336 | * if (IS_ERR(priv->pclk)) |
337 | * return PTR_ERR(priv->pclk); |
338 | * |
339 | * // Further setup, display pipeline etc |
340 | * |
341 | * platform_set_drvdata(pdev, drm); |
342 | * |
343 | * drm_mode_config_reset(drm); |
344 | * |
345 | * ret = drm_dev_register(drm); |
346 | * if (ret) |
347 | * return ret; |
348 | * |
349 | * drm_fbdev_generic_setup(drm, 32); |
350 | * |
351 | * return 0; |
352 | * } |
353 | * |
354 | * // This function is called before the devm_ resources are released |
355 | * static int driver_remove(struct platform_device *pdev) |
356 | * { |
357 | * struct drm_device *drm = platform_get_drvdata(pdev); |
358 | * |
359 | * drm_dev_unregister(drm); |
360 | * drm_atomic_helper_shutdown(drm) |
361 | * |
362 | * return 0; |
363 | * } |
364 | * |
365 | * // This function is called on kernel restart and shutdown |
366 | * static void driver_shutdown(struct platform_device *pdev) |
367 | * { |
368 | * drm_atomic_helper_shutdown(platform_get_drvdata(pdev)); |
369 | * } |
370 | * |
371 | * static int __maybe_unused driver_pm_suspend(struct device *dev) |
372 | * { |
373 | * return drm_mode_config_helper_suspend(dev_get_drvdata(dev)); |
374 | * } |
375 | * |
376 | * static int __maybe_unused driver_pm_resume(struct device *dev) |
377 | * { |
378 | * drm_mode_config_helper_resume(dev_get_drvdata(dev)); |
379 | * |
380 | * return 0; |
381 | * } |
382 | * |
383 | * static const struct dev_pm_ops driver_pm_ops = { |
384 | * SET_SYSTEM_SLEEP_PM_OPS(driver_pm_suspend, driver_pm_resume) |
385 | * }; |
386 | * |
387 | * static struct platform_driver driver_driver = { |
388 | * .driver = { |
389 | * [...] |
390 | * .pm = &driver_pm_ops, |
391 | * }, |
392 | * .probe = driver_probe, |
393 | * .remove = driver_remove, |
394 | * .shutdown = driver_shutdown, |
395 | * }; |
396 | * module_platform_driver(driver_driver); |
397 | * |
398 | * Drivers that want to support device unplugging (USB, DT overlay unload) should |
399 | * use drm_dev_unplug() instead of drm_dev_unregister(). The driver must protect |
400 | * regions that is accessing device resources to prevent use after they're |
401 | * released. This is done using drm_dev_enter() and drm_dev_exit(). There is one |
402 | * shortcoming however, drm_dev_unplug() marks the drm_device as unplugged before |
403 | * drm_atomic_helper_shutdown() is called. This means that if the disable code |
404 | * paths are protected, they will not run on regular driver module unload, |
405 | * possibly leaving the hardware enabled. |
406 | */ |
407 | |
408 | /** |
409 | * drm_put_dev - Unregister and release a DRM device |
410 | * @dev: DRM device |
411 | * |
412 | * Called at module unload time or when a PCI device is unplugged. |
413 | * |
414 | * Cleans up all DRM device, calling drm_lastclose(). |
415 | * |
416 | * Note: Use of this function is deprecated. It will eventually go away |
417 | * completely. Please use drm_dev_unregister() and drm_dev_put() explicitly |
418 | * instead to make sure that the device isn't userspace accessible any more |
419 | * while teardown is in progress, ensuring that userspace can't access an |
420 | * inconsistent state. |
421 | */ |
422 | void drm_put_dev(struct drm_device *dev) |
423 | { |
424 | DRM_DEBUG("\n" ); |
425 | |
426 | if (!dev) { |
427 | DRM_ERROR("cleanup called no dev\n" ); |
428 | return; |
429 | } |
430 | |
431 | drm_dev_unregister(dev); |
432 | drm_dev_put(dev); |
433 | } |
434 | EXPORT_SYMBOL(drm_put_dev); |
435 | |
436 | /** |
437 | * drm_dev_enter - Enter device critical section |
438 | * @dev: DRM device |
439 | * @idx: Pointer to index that will be passed to the matching drm_dev_exit() |
440 | * |
441 | * This function marks and protects the beginning of a section that should not |
442 | * be entered after the device has been unplugged. The section end is marked |
443 | * with drm_dev_exit(). Calls to this function can be nested. |
444 | * |
445 | * Returns: |
446 | * True if it is OK to enter the section, false otherwise. |
447 | */ |
448 | bool drm_dev_enter(struct drm_device *dev, int *idx) |
449 | { |
450 | *idx = srcu_read_lock(ssp: &drm_unplug_srcu); |
451 | |
452 | if (dev->unplugged) { |
453 | srcu_read_unlock(ssp: &drm_unplug_srcu, idx: *idx); |
454 | return false; |
455 | } |
456 | |
457 | return true; |
458 | } |
459 | EXPORT_SYMBOL(drm_dev_enter); |
460 | |
461 | /** |
462 | * drm_dev_exit - Exit device critical section |
463 | * @idx: index returned from drm_dev_enter() |
464 | * |
465 | * This function marks the end of a section that should not be entered after |
466 | * the device has been unplugged. |
467 | */ |
468 | void drm_dev_exit(int idx) |
469 | { |
470 | srcu_read_unlock(ssp: &drm_unplug_srcu, idx); |
471 | } |
472 | EXPORT_SYMBOL(drm_dev_exit); |
473 | |
474 | /** |
475 | * drm_dev_unplug - unplug a DRM device |
476 | * @dev: DRM device |
477 | * |
478 | * This unplugs a hotpluggable DRM device, which makes it inaccessible to |
479 | * userspace operations. Entry-points can use drm_dev_enter() and |
480 | * drm_dev_exit() to protect device resources in a race free manner. This |
481 | * essentially unregisters the device like drm_dev_unregister(), but can be |
482 | * called while there are still open users of @dev. |
483 | */ |
484 | void drm_dev_unplug(struct drm_device *dev) |
485 | { |
486 | /* |
487 | * After synchronizing any critical read section is guaranteed to see |
488 | * the new value of ->unplugged, and any critical section which might |
489 | * still have seen the old value of ->unplugged is guaranteed to have |
490 | * finished. |
491 | */ |
492 | dev->unplugged = true; |
493 | synchronize_srcu(ssp: &drm_unplug_srcu); |
494 | |
495 | drm_dev_unregister(dev); |
496 | |
497 | /* Clear all CPU mappings pointing to this device */ |
498 | unmap_mapping_range(mapping: dev->anon_inode->i_mapping, holebegin: 0, holelen: 0, even_cows: 1); |
499 | } |
500 | EXPORT_SYMBOL(drm_dev_unplug); |
501 | |
502 | /* |
503 | * DRM internal mount |
504 | * We want to be able to allocate our own "struct address_space" to control |
505 | * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow |
506 | * stand-alone address_space objects, so we need an underlying inode. As there |
507 | * is no way to allocate an independent inode easily, we need a fake internal |
508 | * VFS mount-point. |
509 | * |
510 | * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free() |
511 | * frees it again. You are allowed to use iget() and iput() to get references to |
512 | * the inode. But each drm_fs_inode_new() call must be paired with exactly one |
513 | * drm_fs_inode_free() call (which does not have to be the last iput()). |
514 | * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it |
515 | * between multiple inode-users. You could, technically, call |
516 | * iget() + drm_fs_inode_free() directly after alloc and sometime later do an |
517 | * iput(), but this way you'd end up with a new vfsmount for each inode. |
518 | */ |
519 | |
520 | static int drm_fs_cnt; |
521 | static struct vfsmount *drm_fs_mnt; |
522 | |
523 | static int drm_fs_init_fs_context(struct fs_context *fc) |
524 | { |
525 | return init_pseudo(fc, magic: 0x010203ff) ? 0 : -ENOMEM; |
526 | } |
527 | |
528 | static struct file_system_type drm_fs_type = { |
529 | .name = "drm" , |
530 | .owner = THIS_MODULE, |
531 | .init_fs_context = drm_fs_init_fs_context, |
532 | .kill_sb = kill_anon_super, |
533 | }; |
534 | |
535 | static struct inode *drm_fs_inode_new(void) |
536 | { |
537 | struct inode *inode; |
538 | int r; |
539 | |
540 | r = simple_pin_fs(&drm_fs_type, mount: &drm_fs_mnt, count: &drm_fs_cnt); |
541 | if (r < 0) { |
542 | DRM_ERROR("Cannot mount pseudo fs: %d\n" , r); |
543 | return ERR_PTR(error: r); |
544 | } |
545 | |
546 | inode = alloc_anon_inode(drm_fs_mnt->mnt_sb); |
547 | if (IS_ERR(ptr: inode)) |
548 | simple_release_fs(mount: &drm_fs_mnt, count: &drm_fs_cnt); |
549 | |
550 | return inode; |
551 | } |
552 | |
553 | static void drm_fs_inode_free(struct inode *inode) |
554 | { |
555 | if (inode) { |
556 | iput(inode); |
557 | simple_release_fs(mount: &drm_fs_mnt, count: &drm_fs_cnt); |
558 | } |
559 | } |
560 | |
561 | /** |
562 | * DOC: component helper usage recommendations |
563 | * |
564 | * DRM drivers that drive hardware where a logical device consists of a pile of |
565 | * independent hardware blocks are recommended to use the :ref:`component helper |
566 | * library<component>`. For consistency and better options for code reuse the |
567 | * following guidelines apply: |
568 | * |
569 | * - The entire device initialization procedure should be run from the |
570 | * &component_master_ops.master_bind callback, starting with |
571 | * devm_drm_dev_alloc(), then binding all components with |
572 | * component_bind_all() and finishing with drm_dev_register(). |
573 | * |
574 | * - The opaque pointer passed to all components through component_bind_all() |
575 | * should point at &struct drm_device of the device instance, not some driver |
576 | * specific private structure. |
577 | * |
578 | * - The component helper fills the niche where further standardization of |
579 | * interfaces is not practical. When there already is, or will be, a |
580 | * standardized interface like &drm_bridge or &drm_panel, providing its own |
581 | * functions to find such components at driver load time, like |
582 | * drm_of_find_panel_or_bridge(), then the component helper should not be |
583 | * used. |
584 | */ |
585 | |
586 | static void drm_dev_init_release(struct drm_device *dev, void *res) |
587 | { |
588 | drm_legacy_ctxbitmap_cleanup(dev); |
589 | drm_legacy_remove_map_hash(dev); |
590 | drm_fs_inode_free(inode: dev->anon_inode); |
591 | |
592 | put_device(dev: dev->dev); |
593 | /* Prevent use-after-free in drm_managed_release when debugging is |
594 | * enabled. Slightly awkward, but can't really be helped. */ |
595 | dev->dev = NULL; |
596 | mutex_destroy(lock: &dev->master_mutex); |
597 | mutex_destroy(lock: &dev->clientlist_mutex); |
598 | mutex_destroy(lock: &dev->filelist_mutex); |
599 | mutex_destroy(lock: &dev->struct_mutex); |
600 | drm_legacy_destroy_members(dev); |
601 | } |
602 | |
603 | static int drm_dev_init(struct drm_device *dev, |
604 | const struct drm_driver *driver, |
605 | struct device *parent) |
606 | { |
607 | struct inode *inode; |
608 | int ret; |
609 | |
610 | if (!drm_core_init_complete) { |
611 | DRM_ERROR("DRM core is not initialized\n" ); |
612 | return -ENODEV; |
613 | } |
614 | |
615 | if (WARN_ON(!parent)) |
616 | return -EINVAL; |
617 | |
618 | kref_init(kref: &dev->ref); |
619 | dev->dev = get_device(dev: parent); |
620 | dev->driver = driver; |
621 | |
622 | INIT_LIST_HEAD(list: &dev->managed.resources); |
623 | spin_lock_init(&dev->managed.lock); |
624 | |
625 | /* no per-device feature limits by default */ |
626 | dev->driver_features = ~0u; |
627 | |
628 | if (drm_core_check_feature(dev, feature: DRIVER_COMPUTE_ACCEL) && |
629 | (drm_core_check_feature(dev, feature: DRIVER_RENDER) || |
630 | drm_core_check_feature(dev, feature: DRIVER_MODESET))) { |
631 | DRM_ERROR("DRM driver can't be both a compute acceleration and graphics driver\n" ); |
632 | return -EINVAL; |
633 | } |
634 | |
635 | drm_legacy_init_members(dev); |
636 | INIT_LIST_HEAD(list: &dev->filelist); |
637 | INIT_LIST_HEAD(list: &dev->filelist_internal); |
638 | INIT_LIST_HEAD(list: &dev->clientlist); |
639 | INIT_LIST_HEAD(list: &dev->vblank_event_list); |
640 | |
641 | spin_lock_init(&dev->event_lock); |
642 | mutex_init(&dev->struct_mutex); |
643 | mutex_init(&dev->filelist_mutex); |
644 | mutex_init(&dev->clientlist_mutex); |
645 | mutex_init(&dev->master_mutex); |
646 | |
647 | ret = drmm_add_action_or_reset(dev, drm_dev_init_release, NULL); |
648 | if (ret) |
649 | return ret; |
650 | |
651 | inode = drm_fs_inode_new(); |
652 | if (IS_ERR(ptr: inode)) { |
653 | ret = PTR_ERR(ptr: inode); |
654 | DRM_ERROR("Cannot allocate anonymous inode: %d\n" , ret); |
655 | goto err; |
656 | } |
657 | |
658 | dev->anon_inode = inode; |
659 | |
660 | if (drm_core_check_feature(dev, feature: DRIVER_COMPUTE_ACCEL)) { |
661 | ret = drm_minor_alloc(dev, type: DRM_MINOR_ACCEL); |
662 | if (ret) |
663 | goto err; |
664 | } else { |
665 | if (drm_core_check_feature(dev, feature: DRIVER_RENDER)) { |
666 | ret = drm_minor_alloc(dev, type: DRM_MINOR_RENDER); |
667 | if (ret) |
668 | goto err; |
669 | } |
670 | |
671 | ret = drm_minor_alloc(dev, type: DRM_MINOR_PRIMARY); |
672 | if (ret) |
673 | goto err; |
674 | } |
675 | |
676 | ret = drm_legacy_create_map_hash(dev); |
677 | if (ret) |
678 | goto err; |
679 | |
680 | drm_legacy_ctxbitmap_init(dev); |
681 | |
682 | if (drm_core_check_feature(dev, feature: DRIVER_GEM)) { |
683 | ret = drm_gem_init(dev); |
684 | if (ret) { |
685 | DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n" ); |
686 | goto err; |
687 | } |
688 | } |
689 | |
690 | dev->unique = drmm_kstrdup(dev, s: dev_name(dev: parent), GFP_KERNEL); |
691 | if (!dev->unique) { |
692 | ret = -ENOMEM; |
693 | goto err; |
694 | } |
695 | |
696 | if (drm_core_check_feature(dev, feature: DRIVER_COMPUTE_ACCEL)) |
697 | accel_debugfs_init(dev); |
698 | else |
699 | drm_debugfs_dev_init(dev, root: drm_debugfs_root); |
700 | |
701 | return 0; |
702 | |
703 | err: |
704 | drm_managed_release(dev); |
705 | |
706 | return ret; |
707 | } |
708 | |
709 | static void devm_drm_dev_init_release(void *data) |
710 | { |
711 | drm_dev_put(dev: data); |
712 | } |
713 | |
714 | static int devm_drm_dev_init(struct device *parent, |
715 | struct drm_device *dev, |
716 | const struct drm_driver *driver) |
717 | { |
718 | int ret; |
719 | |
720 | ret = drm_dev_init(dev, driver, parent); |
721 | if (ret) |
722 | return ret; |
723 | |
724 | return devm_add_action_or_reset(parent, |
725 | devm_drm_dev_init_release, dev); |
726 | } |
727 | |
728 | void *__devm_drm_dev_alloc(struct device *parent, |
729 | const struct drm_driver *driver, |
730 | size_t size, size_t offset) |
731 | { |
732 | void *container; |
733 | struct drm_device *drm; |
734 | int ret; |
735 | |
736 | container = kzalloc(size, GFP_KERNEL); |
737 | if (!container) |
738 | return ERR_PTR(error: -ENOMEM); |
739 | |
740 | drm = container + offset; |
741 | ret = devm_drm_dev_init(parent, dev: drm, driver); |
742 | if (ret) { |
743 | kfree(objp: container); |
744 | return ERR_PTR(error: ret); |
745 | } |
746 | drmm_add_final_kfree(dev: drm, container); |
747 | |
748 | return container; |
749 | } |
750 | EXPORT_SYMBOL(__devm_drm_dev_alloc); |
751 | |
752 | /** |
753 | * drm_dev_alloc - Allocate new DRM device |
754 | * @driver: DRM driver to allocate device for |
755 | * @parent: Parent device object |
756 | * |
757 | * This is the deprecated version of devm_drm_dev_alloc(), which does not support |
758 | * subclassing through embedding the struct &drm_device in a driver private |
759 | * structure, and which does not support automatic cleanup through devres. |
760 | * |
761 | * RETURNS: |
762 | * Pointer to new DRM device, or ERR_PTR on failure. |
763 | */ |
764 | struct drm_device *drm_dev_alloc(const struct drm_driver *driver, |
765 | struct device *parent) |
766 | { |
767 | struct drm_device *dev; |
768 | int ret; |
769 | |
770 | dev = kzalloc(size: sizeof(*dev), GFP_KERNEL); |
771 | if (!dev) |
772 | return ERR_PTR(error: -ENOMEM); |
773 | |
774 | ret = drm_dev_init(dev, driver, parent); |
775 | if (ret) { |
776 | kfree(objp: dev); |
777 | return ERR_PTR(error: ret); |
778 | } |
779 | |
780 | drmm_add_final_kfree(dev, container: dev); |
781 | |
782 | return dev; |
783 | } |
784 | EXPORT_SYMBOL(drm_dev_alloc); |
785 | |
786 | static void drm_dev_release(struct kref *ref) |
787 | { |
788 | struct drm_device *dev = container_of(ref, struct drm_device, ref); |
789 | |
790 | /* Just in case register/unregister was never called */ |
791 | drm_debugfs_dev_fini(dev); |
792 | |
793 | if (dev->driver->release) |
794 | dev->driver->release(dev); |
795 | |
796 | drm_managed_release(dev); |
797 | |
798 | kfree(objp: dev->managed.final_kfree); |
799 | } |
800 | |
801 | /** |
802 | * drm_dev_get - Take reference of a DRM device |
803 | * @dev: device to take reference of or NULL |
804 | * |
805 | * This increases the ref-count of @dev by one. You *must* already own a |
806 | * reference when calling this. Use drm_dev_put() to drop this reference |
807 | * again. |
808 | * |
809 | * This function never fails. However, this function does not provide *any* |
810 | * guarantee whether the device is alive or running. It only provides a |
811 | * reference to the object and the memory associated with it. |
812 | */ |
813 | void drm_dev_get(struct drm_device *dev) |
814 | { |
815 | if (dev) |
816 | kref_get(kref: &dev->ref); |
817 | } |
818 | EXPORT_SYMBOL(drm_dev_get); |
819 | |
820 | /** |
821 | * drm_dev_put - Drop reference of a DRM device |
822 | * @dev: device to drop reference of or NULL |
823 | * |
824 | * This decreases the ref-count of @dev by one. The device is destroyed if the |
825 | * ref-count drops to zero. |
826 | */ |
827 | void drm_dev_put(struct drm_device *dev) |
828 | { |
829 | if (dev) |
830 | kref_put(kref: &dev->ref, release: drm_dev_release); |
831 | } |
832 | EXPORT_SYMBOL(drm_dev_put); |
833 | |
834 | static int create_compat_control_link(struct drm_device *dev) |
835 | { |
836 | struct drm_minor *minor; |
837 | char *name; |
838 | int ret; |
839 | |
840 | if (!drm_core_check_feature(dev, feature: DRIVER_MODESET)) |
841 | return 0; |
842 | |
843 | minor = *drm_minor_get_slot(dev, type: DRM_MINOR_PRIMARY); |
844 | if (!minor) |
845 | return 0; |
846 | |
847 | /* |
848 | * Some existing userspace out there uses the existing of the controlD* |
849 | * sysfs files to figure out whether it's a modeset driver. It only does |
850 | * readdir, hence a symlink is sufficient (and the least confusing |
851 | * option). Otherwise controlD* is entirely unused. |
852 | * |
853 | * Old controlD chardev have been allocated in the range |
854 | * 64-127. |
855 | */ |
856 | name = kasprintf(GFP_KERNEL, fmt: "controlD%d" , minor->index + 64); |
857 | if (!name) |
858 | return -ENOMEM; |
859 | |
860 | ret = sysfs_create_link(kobj: minor->kdev->kobj.parent, |
861 | target: &minor->kdev->kobj, |
862 | name); |
863 | |
864 | kfree(objp: name); |
865 | |
866 | return ret; |
867 | } |
868 | |
869 | static void remove_compat_control_link(struct drm_device *dev) |
870 | { |
871 | struct drm_minor *minor; |
872 | char *name; |
873 | |
874 | if (!drm_core_check_feature(dev, feature: DRIVER_MODESET)) |
875 | return; |
876 | |
877 | minor = *drm_minor_get_slot(dev, type: DRM_MINOR_PRIMARY); |
878 | if (!minor) |
879 | return; |
880 | |
881 | name = kasprintf(GFP_KERNEL, fmt: "controlD%d" , minor->index + 64); |
882 | if (!name) |
883 | return; |
884 | |
885 | sysfs_remove_link(kobj: minor->kdev->kobj.parent, name); |
886 | |
887 | kfree(objp: name); |
888 | } |
889 | |
890 | /** |
891 | * drm_dev_register - Register DRM device |
892 | * @dev: Device to register |
893 | * @flags: Flags passed to the driver's .load() function |
894 | * |
895 | * Register the DRM device @dev with the system, advertise device to user-space |
896 | * and start normal device operation. @dev must be initialized via drm_dev_init() |
897 | * previously. |
898 | * |
899 | * Never call this twice on any device! |
900 | * |
901 | * NOTE: To ensure backward compatibility with existing drivers method this |
902 | * function calls the &drm_driver.load method after registering the device |
903 | * nodes, creating race conditions. Usage of the &drm_driver.load methods is |
904 | * therefore deprecated, drivers must perform all initialization before calling |
905 | * drm_dev_register(). |
906 | * |
907 | * RETURNS: |
908 | * 0 on success, negative error code on failure. |
909 | */ |
910 | int drm_dev_register(struct drm_device *dev, unsigned long flags) |
911 | { |
912 | const struct drm_driver *driver = dev->driver; |
913 | int ret; |
914 | |
915 | if (!driver->load) |
916 | drm_mode_config_validate(dev); |
917 | |
918 | WARN_ON(!dev->managed.final_kfree); |
919 | |
920 | if (drm_dev_needs_global_mutex(dev)) |
921 | mutex_lock(&drm_global_mutex); |
922 | |
923 | if (drm_core_check_feature(dev, feature: DRIVER_COMPUTE_ACCEL)) |
924 | accel_debugfs_register(dev); |
925 | else |
926 | drm_debugfs_dev_register(dev); |
927 | |
928 | ret = drm_minor_register(dev, type: DRM_MINOR_RENDER); |
929 | if (ret) |
930 | goto err_minors; |
931 | |
932 | ret = drm_minor_register(dev, type: DRM_MINOR_PRIMARY); |
933 | if (ret) |
934 | goto err_minors; |
935 | |
936 | ret = drm_minor_register(dev, type: DRM_MINOR_ACCEL); |
937 | if (ret) |
938 | goto err_minors; |
939 | |
940 | ret = create_compat_control_link(dev); |
941 | if (ret) |
942 | goto err_minors; |
943 | |
944 | dev->registered = true; |
945 | |
946 | if (driver->load) { |
947 | ret = driver->load(dev, flags); |
948 | if (ret) |
949 | goto err_minors; |
950 | } |
951 | |
952 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) |
953 | drm_modeset_register_all(dev); |
954 | |
955 | DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n" , |
956 | driver->name, driver->major, driver->minor, |
957 | driver->patchlevel, driver->date, |
958 | dev->dev ? dev_name(dev->dev) : "virtual device" , |
959 | dev->primary ? dev->primary->index : dev->accel->index); |
960 | |
961 | goto out_unlock; |
962 | |
963 | err_minors: |
964 | remove_compat_control_link(dev); |
965 | drm_minor_unregister(dev, type: DRM_MINOR_ACCEL); |
966 | drm_minor_unregister(dev, type: DRM_MINOR_PRIMARY); |
967 | drm_minor_unregister(dev, type: DRM_MINOR_RENDER); |
968 | out_unlock: |
969 | if (drm_dev_needs_global_mutex(dev)) |
970 | mutex_unlock(lock: &drm_global_mutex); |
971 | return ret; |
972 | } |
973 | EXPORT_SYMBOL(drm_dev_register); |
974 | |
975 | /** |
976 | * drm_dev_unregister - Unregister DRM device |
977 | * @dev: Device to unregister |
978 | * |
979 | * Unregister the DRM device from the system. This does the reverse of |
980 | * drm_dev_register() but does not deallocate the device. The caller must call |
981 | * drm_dev_put() to drop their final reference, unless it is managed with devres |
982 | * (as devices allocated with devm_drm_dev_alloc() are), in which case there is |
983 | * already an unwind action registered. |
984 | * |
985 | * A special form of unregistering for hotpluggable devices is drm_dev_unplug(), |
986 | * which can be called while there are still open users of @dev. |
987 | * |
988 | * This should be called first in the device teardown code to make sure |
989 | * userspace can't access the device instance any more. |
990 | */ |
991 | void drm_dev_unregister(struct drm_device *dev) |
992 | { |
993 | if (drm_core_check_feature(dev, feature: DRIVER_LEGACY)) |
994 | drm_lastclose(dev); |
995 | |
996 | dev->registered = false; |
997 | |
998 | drm_client_dev_unregister(dev); |
999 | |
1000 | if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) |
1001 | drm_modeset_unregister_all(dev); |
1002 | |
1003 | if (dev->driver->unload) |
1004 | dev->driver->unload(dev); |
1005 | |
1006 | drm_legacy_pci_agp_destroy(dev); |
1007 | drm_legacy_rmmaps(dev); |
1008 | |
1009 | remove_compat_control_link(dev); |
1010 | drm_minor_unregister(dev, type: DRM_MINOR_ACCEL); |
1011 | drm_minor_unregister(dev, type: DRM_MINOR_PRIMARY); |
1012 | drm_minor_unregister(dev, type: DRM_MINOR_RENDER); |
1013 | drm_debugfs_dev_fini(dev); |
1014 | } |
1015 | EXPORT_SYMBOL(drm_dev_unregister); |
1016 | |
1017 | /* |
1018 | * DRM Core |
1019 | * The DRM core module initializes all global DRM objects and makes them |
1020 | * available to drivers. Once setup, drivers can probe their respective |
1021 | * devices. |
1022 | * Currently, core management includes: |
1023 | * - The "DRM-Global" key/value database |
1024 | * - Global ID management for connectors |
1025 | * - DRM major number allocation |
1026 | * - DRM minor management |
1027 | * - DRM sysfs class |
1028 | * - DRM debugfs root |
1029 | * |
1030 | * Furthermore, the DRM core provides dynamic char-dev lookups. For each |
1031 | * interface registered on a DRM device, you can request minor numbers from DRM |
1032 | * core. DRM core takes care of major-number management and char-dev |
1033 | * registration. A stub ->open() callback forwards any open() requests to the |
1034 | * registered minor. |
1035 | */ |
1036 | |
1037 | static int drm_stub_open(struct inode *inode, struct file *filp) |
1038 | { |
1039 | const struct file_operations *new_fops; |
1040 | struct drm_minor *minor; |
1041 | int err; |
1042 | |
1043 | DRM_DEBUG("\n" ); |
1044 | |
1045 | minor = drm_minor_acquire(minor_id: iminor(inode)); |
1046 | if (IS_ERR(ptr: minor)) |
1047 | return PTR_ERR(ptr: minor); |
1048 | |
1049 | new_fops = fops_get(minor->dev->driver->fops); |
1050 | if (!new_fops) { |
1051 | err = -ENODEV; |
1052 | goto out; |
1053 | } |
1054 | |
1055 | replace_fops(filp, new_fops); |
1056 | if (filp->f_op->open) |
1057 | err = filp->f_op->open(inode, filp); |
1058 | else |
1059 | err = 0; |
1060 | |
1061 | out: |
1062 | drm_minor_release(minor); |
1063 | |
1064 | return err; |
1065 | } |
1066 | |
1067 | static const struct file_operations drm_stub_fops = { |
1068 | .owner = THIS_MODULE, |
1069 | .open = drm_stub_open, |
1070 | .llseek = noop_llseek, |
1071 | }; |
1072 | |
1073 | static void drm_core_exit(void) |
1074 | { |
1075 | drm_privacy_screen_lookup_exit(); |
1076 | accel_core_exit(); |
1077 | unregister_chrdev(DRM_MAJOR, name: "drm" ); |
1078 | debugfs_remove(dentry: drm_debugfs_root); |
1079 | drm_sysfs_destroy(); |
1080 | idr_destroy(&drm_minors_idr); |
1081 | drm_connector_ida_destroy(); |
1082 | } |
1083 | |
1084 | static int __init drm_core_init(void) |
1085 | { |
1086 | int ret; |
1087 | |
1088 | drm_connector_ida_init(); |
1089 | idr_init(idr: &drm_minors_idr); |
1090 | drm_memcpy_init_early(); |
1091 | |
1092 | ret = drm_sysfs_init(); |
1093 | if (ret < 0) { |
1094 | DRM_ERROR("Cannot create DRM class: %d\n" , ret); |
1095 | goto error; |
1096 | } |
1097 | |
1098 | drm_debugfs_root = debugfs_create_dir(name: "dri" , NULL); |
1099 | |
1100 | ret = register_chrdev(DRM_MAJOR, name: "drm" , fops: &drm_stub_fops); |
1101 | if (ret < 0) |
1102 | goto error; |
1103 | |
1104 | ret = accel_core_init(); |
1105 | if (ret < 0) |
1106 | goto error; |
1107 | |
1108 | drm_privacy_screen_lookup_init(); |
1109 | |
1110 | drm_core_init_complete = true; |
1111 | |
1112 | DRM_DEBUG("Initialized\n" ); |
1113 | return 0; |
1114 | |
1115 | error: |
1116 | drm_core_exit(); |
1117 | return ret; |
1118 | } |
1119 | |
1120 | module_init(drm_core_init); |
1121 | module_exit(drm_core_exit); |
1122 | |