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);