1 /* 2 * Created: Fri Jan 19 10:48:35 2001 by faith@acm.org 3 * 4 * Copyright 2001 VA Linux Systems, Inc., Sunnyvale, California. 5 * All Rights Reserved. 6 * 7 * Author Rickard E. (Rik) Faith <faith@valinux.com> 8 * 9 * Permission is hereby granted, free of charge, to any person obtaining a 10 * copy of this software and associated documentation files (the "Software"), 11 * to deal in the Software without restriction, including without limitation 12 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 13 * and/or sell copies of the Software, and to permit persons to whom the 14 * Software is furnished to do so, subject to the following conditions: 15 * 16 * The above copyright notice and this permission notice (including the next 17 * paragraph) shall be included in all copies or substantial portions of the 18 * Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 23 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 24 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 26 * DEALINGS IN THE SOFTWARE. 27 */ 28 29 #include <linux/debugfs.h> 30 #include <linux/fs.h> 31 #include <linux/module.h> 32 #include <linux/moduleparam.h> 33 #include <linux/mount.h> 34 #include <linux/slab.h> 35 #include <drm/drmP.h> 36 #include <drm/drm_core.h> 37 #include "drm_legacy.h" 38 #include "drm_internal.h" 39 40 /* 41 * drm_debug: Enable debug output. 42 * Bitmask of DRM_UT_x. See include/drm/drmP.h for details. 43 */ 44 unsigned int drm_debug = 0; 45 EXPORT_SYMBOL(drm_debug); 46 47 MODULE_AUTHOR(CORE_AUTHOR); 48 MODULE_DESCRIPTION(CORE_DESC); 49 MODULE_LICENSE("GPL and additional rights"); 50 MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n" 51 "\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n" 52 "\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n" 53 "\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n" 54 "\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n" 55 "\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n" 56 "\t\tBit 5 (0x20) will enable VBL messages (vblank code)"); 57 module_param_named(debug, drm_debug, int, 0600); 58 59 static DEFINE_SPINLOCK(drm_minor_lock); 60 static struct idr drm_minors_idr; 61 62 static struct dentry *drm_debugfs_root; 63 64 void drm_err(const char *format, ...) 65 { 66 struct va_format vaf; 67 va_list args; 68 69 va_start(args, format); 70 71 vaf.fmt = format; 72 vaf.va = &args; 73 74 printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV", 75 __builtin_return_address(0), &vaf); 76 77 va_end(args); 78 } 79 EXPORT_SYMBOL(drm_err); 80 81 void drm_ut_debug_printk(const char *function_name, const char *format, ...) 82 { 83 struct va_format vaf; 84 va_list args; 85 86 va_start(args, format); 87 vaf.fmt = format; 88 vaf.va = &args; 89 90 printk(KERN_DEBUG "[" DRM_NAME ":%s] %pV", function_name, &vaf); 91 92 va_end(args); 93 } 94 EXPORT_SYMBOL(drm_ut_debug_printk); 95 96 struct drm_master *drm_master_create(struct drm_minor *minor) 97 { 98 struct drm_master *master; 99 100 master = kzalloc(sizeof(*master), GFP_KERNEL); 101 if (!master) 102 return NULL; 103 104 kref_init(&master->refcount); 105 spin_lock_init(&master->lock.spinlock); 106 init_waitqueue_head(&master->lock.lock_queue); 107 idr_init(&master->magic_map); 108 master->minor = minor; 109 110 return master; 111 } 112 113 struct drm_master *drm_master_get(struct drm_master *master) 114 { 115 kref_get(&master->refcount); 116 return master; 117 } 118 EXPORT_SYMBOL(drm_master_get); 119 120 static void drm_master_destroy(struct kref *kref) 121 { 122 struct drm_master *master = container_of(kref, struct drm_master, refcount); 123 struct drm_device *dev = master->minor->dev; 124 125 if (dev->driver->master_destroy) 126 dev->driver->master_destroy(dev, master); 127 128 drm_legacy_master_rmmaps(dev, master); 129 130 idr_destroy(&master->magic_map); 131 kfree(master->unique); 132 kfree(master); 133 } 134 135 void drm_master_put(struct drm_master **master) 136 { 137 kref_put(&(*master)->refcount, drm_master_destroy); 138 *master = NULL; 139 } 140 EXPORT_SYMBOL(drm_master_put); 141 142 int drm_setmaster_ioctl(struct drm_device *dev, void *data, 143 struct drm_file *file_priv) 144 { 145 int ret = 0; 146 147 mutex_lock(&dev->master_mutex); 148 if (file_priv->is_master) 149 goto out_unlock; 150 151 if (file_priv->minor->master) { 152 ret = -EINVAL; 153 goto out_unlock; 154 } 155 156 if (!file_priv->master) { 157 ret = -EINVAL; 158 goto out_unlock; 159 } 160 161 if (!file_priv->allowed_master) { 162 ret = drm_new_set_master(dev, file_priv); 163 goto out_unlock; 164 } 165 166 file_priv->minor->master = drm_master_get(file_priv->master); 167 file_priv->is_master = 1; 168 if (dev->driver->master_set) { 169 ret = dev->driver->master_set(dev, file_priv, false); 170 if (unlikely(ret != 0)) { 171 file_priv->is_master = 0; 172 drm_master_put(&file_priv->minor->master); 173 } 174 } 175 176 out_unlock: 177 mutex_unlock(&dev->master_mutex); 178 return ret; 179 } 180 181 int drm_dropmaster_ioctl(struct drm_device *dev, void *data, 182 struct drm_file *file_priv) 183 { 184 int ret = -EINVAL; 185 186 mutex_lock(&dev->master_mutex); 187 if (!file_priv->is_master) 188 goto out_unlock; 189 190 if (!file_priv->minor->master) 191 goto out_unlock; 192 193 ret = 0; 194 if (dev->driver->master_drop) 195 dev->driver->master_drop(dev, file_priv, false); 196 drm_master_put(&file_priv->minor->master); 197 file_priv->is_master = 0; 198 199 out_unlock: 200 mutex_unlock(&dev->master_mutex); 201 return ret; 202 } 203 204 /* 205 * DRM Minors 206 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each 207 * of them is represented by a drm_minor object. Depending on the capabilities 208 * of the device-driver, different interfaces are registered. 209 * 210 * Minors can be accessed via dev->$minor_name. This pointer is either 211 * NULL or a valid drm_minor pointer and stays valid as long as the device is 212 * valid. This means, DRM minors have the same life-time as the underlying 213 * device. However, this doesn't mean that the minor is active. Minors are 214 * registered and unregistered dynamically according to device-state. 215 */ 216 217 static struct drm_minor **drm_minor_get_slot(struct drm_device *dev, 218 unsigned int type) 219 { 220 switch (type) { 221 case DRM_MINOR_LEGACY: 222 return &dev->primary; 223 case DRM_MINOR_RENDER: 224 return &dev->render; 225 case DRM_MINOR_CONTROL: 226 return &dev->control; 227 default: 228 return NULL; 229 } 230 } 231 232 static int drm_minor_alloc(struct drm_device *dev, unsigned int type) 233 { 234 struct drm_minor *minor; 235 unsigned long flags; 236 int r; 237 238 minor = kzalloc(sizeof(*minor), GFP_KERNEL); 239 if (!minor) 240 return -ENOMEM; 241 242 minor->type = type; 243 minor->dev = dev; 244 245 idr_preload(GFP_KERNEL); 246 spin_lock_irqsave(&drm_minor_lock, flags); 247 r = idr_alloc(&drm_minors_idr, 248 NULL, 249 64 * type, 250 64 * (type + 1), 251 GFP_NOWAIT); 252 spin_unlock_irqrestore(&drm_minor_lock, flags); 253 idr_preload_end(); 254 255 if (r < 0) 256 goto err_free; 257 258 minor->index = r; 259 260 minor->kdev = drm_sysfs_minor_alloc(minor); 261 if (IS_ERR(minor->kdev)) { 262 r = PTR_ERR(minor->kdev); 263 goto err_index; 264 } 265 266 *drm_minor_get_slot(dev, type) = minor; 267 return 0; 268 269 err_index: 270 spin_lock_irqsave(&drm_minor_lock, flags); 271 idr_remove(&drm_minors_idr, minor->index); 272 spin_unlock_irqrestore(&drm_minor_lock, flags); 273 err_free: 274 kfree(minor); 275 return r; 276 } 277 278 static void drm_minor_free(struct drm_device *dev, unsigned int type) 279 { 280 struct drm_minor **slot, *minor; 281 unsigned long flags; 282 283 slot = drm_minor_get_slot(dev, type); 284 minor = *slot; 285 if (!minor) 286 return; 287 288 put_device(minor->kdev); 289 290 spin_lock_irqsave(&drm_minor_lock, flags); 291 idr_remove(&drm_minors_idr, minor->index); 292 spin_unlock_irqrestore(&drm_minor_lock, flags); 293 294 kfree(minor); 295 *slot = NULL; 296 } 297 298 static int drm_minor_register(struct drm_device *dev, unsigned int type) 299 { 300 struct drm_minor *minor; 301 unsigned long flags; 302 int ret; 303 304 DRM_DEBUG("\n"); 305 306 minor = *drm_minor_get_slot(dev, type); 307 if (!minor) 308 return 0; 309 310 ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root); 311 if (ret) { 312 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n"); 313 return ret; 314 } 315 316 ret = device_add(minor->kdev); 317 if (ret) 318 goto err_debugfs; 319 320 /* replace NULL with @minor so lookups will succeed from now on */ 321 spin_lock_irqsave(&drm_minor_lock, flags); 322 idr_replace(&drm_minors_idr, minor, minor->index); 323 spin_unlock_irqrestore(&drm_minor_lock, flags); 324 325 DRM_DEBUG("new minor registered %d\n", minor->index); 326 return 0; 327 328 err_debugfs: 329 drm_debugfs_cleanup(minor); 330 return ret; 331 } 332 333 static void drm_minor_unregister(struct drm_device *dev, unsigned int type) 334 { 335 struct drm_minor *minor; 336 unsigned long flags; 337 338 minor = *drm_minor_get_slot(dev, type); 339 if (!minor || !device_is_registered(minor->kdev)) 340 return; 341 342 /* replace @minor with NULL so lookups will fail from now on */ 343 spin_lock_irqsave(&drm_minor_lock, flags); 344 idr_replace(&drm_minors_idr, NULL, minor->index); 345 spin_unlock_irqrestore(&drm_minor_lock, flags); 346 347 device_del(minor->kdev); 348 dev_set_drvdata(minor->kdev, NULL); /* safety belt */ 349 drm_debugfs_cleanup(minor); 350 } 351 352 /** 353 * drm_minor_acquire - Acquire a DRM minor 354 * @minor_id: Minor ID of the DRM-minor 355 * 356 * Looks up the given minor-ID and returns the respective DRM-minor object. The 357 * refence-count of the underlying device is increased so you must release this 358 * object with drm_minor_release(). 359 * 360 * As long as you hold this minor, it is guaranteed that the object and the 361 * minor->dev pointer will stay valid! However, the device may get unplugged and 362 * unregistered while you hold the minor. 363 * 364 * Returns: 365 * Pointer to minor-object with increased device-refcount, or PTR_ERR on 366 * failure. 367 */ 368 struct drm_minor *drm_minor_acquire(unsigned int minor_id) 369 { 370 struct drm_minor *minor; 371 unsigned long flags; 372 373 spin_lock_irqsave(&drm_minor_lock, flags); 374 minor = idr_find(&drm_minors_idr, minor_id); 375 if (minor) 376 drm_dev_ref(minor->dev); 377 spin_unlock_irqrestore(&drm_minor_lock, flags); 378 379 if (!minor) { 380 return ERR_PTR(-ENODEV); 381 } else if (drm_device_is_unplugged(minor->dev)) { 382 drm_dev_unref(minor->dev); 383 return ERR_PTR(-ENODEV); 384 } 385 386 return minor; 387 } 388 389 /** 390 * drm_minor_release - Release DRM minor 391 * @minor: Pointer to DRM minor object 392 * 393 * Release a minor that was previously acquired via drm_minor_acquire(). 394 */ 395 void drm_minor_release(struct drm_minor *minor) 396 { 397 drm_dev_unref(minor->dev); 398 } 399 400 /** 401 * DOC: driver instance overview 402 * 403 * A device instance for a drm driver is represented by struct &drm_device. This 404 * is allocated with drm_dev_alloc(), usually from bus-specific ->probe() 405 * callbacks implemented by the driver. The driver then needs to initialize all 406 * the various subsystems for the drm device like memory management, vblank 407 * handling, modesetting support and intial output configuration plus obviously 408 * initialize all the corresponding hardware bits. An important part of this is 409 * also calling drm_dev_set_unique() to set the userspace-visible unique name of 410 * this device instance. Finally when everything is up and running and ready for 411 * userspace the device instance can be published using drm_dev_register(). 412 * 413 * There is also deprecated support for initalizing device instances using 414 * bus-specific helpers and the ->load() callback. But due to 415 * backwards-compatibility needs the device instance have to be published too 416 * early, which requires unpretty global locking to make safe and is therefore 417 * only support for existing drivers not yet converted to the new scheme. 418 * 419 * When cleaning up a device instance everything needs to be done in reverse: 420 * First unpublish the device instance with drm_dev_unregister(). Then clean up 421 * any other resources allocated at device initialization and drop the driver's 422 * reference to &drm_device using drm_dev_unref(). 423 * 424 * Note that the lifetime rules for &drm_device instance has still a lot of 425 * historical baggage. Hence use the reference counting provided by 426 * drm_dev_ref() and drm_dev_unref() only carefully. 427 * 428 * Also note that embedding of &drm_device is currently not (yet) supported (but 429 * it would be easy to add). Drivers can store driver-private data in the 430 * dev_priv field of &drm_device. 431 */ 432 433 /** 434 * drm_put_dev - Unregister and release a DRM device 435 * @dev: DRM device 436 * 437 * Called at module unload time or when a PCI device is unplugged. 438 * 439 * Cleans up all DRM device, calling drm_lastclose(). 440 * 441 * Note: Use of this function is deprecated. It will eventually go away 442 * completely. Please use drm_dev_unregister() and drm_dev_unref() explicitly 443 * instead to make sure that the device isn't userspace accessible any more 444 * while teardown is in progress, ensuring that userspace can't access an 445 * inconsistent state. 446 */ 447 void drm_put_dev(struct drm_device *dev) 448 { 449 DRM_DEBUG("\n"); 450 451 if (!dev) { 452 DRM_ERROR("cleanup called no dev\n"); 453 return; 454 } 455 456 drm_dev_unregister(dev); 457 drm_dev_unref(dev); 458 } 459 EXPORT_SYMBOL(drm_put_dev); 460 461 void drm_unplug_dev(struct drm_device *dev) 462 { 463 /* for a USB device */ 464 drm_minor_unregister(dev, DRM_MINOR_LEGACY); 465 drm_minor_unregister(dev, DRM_MINOR_RENDER); 466 drm_minor_unregister(dev, DRM_MINOR_CONTROL); 467 468 mutex_lock(&drm_global_mutex); 469 470 drm_device_set_unplugged(dev); 471 472 if (dev->open_count == 0) { 473 drm_put_dev(dev); 474 } 475 mutex_unlock(&drm_global_mutex); 476 } 477 EXPORT_SYMBOL(drm_unplug_dev); 478 479 /* 480 * DRM internal mount 481 * We want to be able to allocate our own "struct address_space" to control 482 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow 483 * stand-alone address_space objects, so we need an underlying inode. As there 484 * is no way to allocate an independent inode easily, we need a fake internal 485 * VFS mount-point. 486 * 487 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free() 488 * frees it again. You are allowed to use iget() and iput() to get references to 489 * the inode. But each drm_fs_inode_new() call must be paired with exactly one 490 * drm_fs_inode_free() call (which does not have to be the last iput()). 491 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it 492 * between multiple inode-users. You could, technically, call 493 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an 494 * iput(), but this way you'd end up with a new vfsmount for each inode. 495 */ 496 497 static int drm_fs_cnt; 498 static struct vfsmount *drm_fs_mnt; 499 500 static const struct dentry_operations drm_fs_dops = { 501 .d_dname = simple_dname, 502 }; 503 504 static const struct super_operations drm_fs_sops = { 505 .statfs = simple_statfs, 506 }; 507 508 static struct dentry *drm_fs_mount(struct file_system_type *fs_type, int flags, 509 const char *dev_name, void *data) 510 { 511 return mount_pseudo(fs_type, 512 "drm:", 513 &drm_fs_sops, 514 &drm_fs_dops, 515 0x010203ff); 516 } 517 518 static struct file_system_type drm_fs_type = { 519 .name = "drm", 520 .owner = THIS_MODULE, 521 .mount = drm_fs_mount, 522 .kill_sb = kill_anon_super, 523 }; 524 525 static struct inode *drm_fs_inode_new(void) 526 { 527 struct inode *inode; 528 int r; 529 530 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt); 531 if (r < 0) { 532 DRM_ERROR("Cannot mount pseudo fs: %d\n", r); 533 return ERR_PTR(r); 534 } 535 536 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb); 537 if (IS_ERR(inode)) 538 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt); 539 540 return inode; 541 } 542 543 static void drm_fs_inode_free(struct inode *inode) 544 { 545 if (inode) { 546 iput(inode); 547 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt); 548 } 549 } 550 551 /** 552 * drm_dev_alloc - Allocate new DRM device 553 * @driver: DRM driver to allocate device for 554 * @parent: Parent device object 555 * 556 * Allocate and initialize a new DRM device. No device registration is done. 557 * Call drm_dev_register() to advertice the device to user space and register it 558 * with other core subsystems. This should be done last in the device 559 * initialization sequence to make sure userspace can't access an inconsistent 560 * state. 561 * 562 * The initial ref-count of the object is 1. Use drm_dev_ref() and 563 * drm_dev_unref() to take and drop further ref-counts. 564 * 565 * Note that for purely virtual devices @parent can be NULL. 566 * 567 * RETURNS: 568 * Pointer to new DRM device, or NULL if out of memory. 569 */ 570 struct drm_device *drm_dev_alloc(struct drm_driver *driver, 571 struct device *parent) 572 { 573 struct drm_device *dev; 574 int ret; 575 576 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 577 if (!dev) 578 return NULL; 579 580 kref_init(&dev->ref); 581 dev->dev = parent; 582 dev->driver = driver; 583 584 INIT_LIST_HEAD(&dev->filelist); 585 INIT_LIST_HEAD(&dev->ctxlist); 586 INIT_LIST_HEAD(&dev->vmalist); 587 INIT_LIST_HEAD(&dev->maplist); 588 INIT_LIST_HEAD(&dev->vblank_event_list); 589 590 spin_lock_init(&dev->buf_lock); 591 spin_lock_init(&dev->event_lock); 592 mutex_init(&dev->struct_mutex); 593 mutex_init(&dev->filelist_mutex); 594 mutex_init(&dev->ctxlist_mutex); 595 mutex_init(&dev->master_mutex); 596 597 dev->anon_inode = drm_fs_inode_new(); 598 if (IS_ERR(dev->anon_inode)) { 599 ret = PTR_ERR(dev->anon_inode); 600 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret); 601 goto err_free; 602 } 603 604 if (drm_core_check_feature(dev, DRIVER_MODESET)) { 605 ret = drm_minor_alloc(dev, DRM_MINOR_CONTROL); 606 if (ret) 607 goto err_minors; 608 609 WARN_ON(driver->suspend || driver->resume); 610 } 611 612 if (drm_core_check_feature(dev, DRIVER_RENDER)) { 613 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER); 614 if (ret) 615 goto err_minors; 616 } 617 618 ret = drm_minor_alloc(dev, DRM_MINOR_LEGACY); 619 if (ret) 620 goto err_minors; 621 622 if (drm_ht_create(&dev->map_hash, 12)) 623 goto err_minors; 624 625 drm_legacy_ctxbitmap_init(dev); 626 627 if (drm_core_check_feature(dev, DRIVER_GEM)) { 628 ret = drm_gem_init(dev); 629 if (ret) { 630 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n"); 631 goto err_ctxbitmap; 632 } 633 } 634 635 if (parent) { 636 ret = drm_dev_set_unique(dev, dev_name(parent)); 637 if (ret) 638 goto err_setunique; 639 } 640 641 return dev; 642 643 err_setunique: 644 if (drm_core_check_feature(dev, DRIVER_GEM)) 645 drm_gem_destroy(dev); 646 err_ctxbitmap: 647 drm_legacy_ctxbitmap_cleanup(dev); 648 drm_ht_remove(&dev->map_hash); 649 err_minors: 650 drm_minor_free(dev, DRM_MINOR_LEGACY); 651 drm_minor_free(dev, DRM_MINOR_RENDER); 652 drm_minor_free(dev, DRM_MINOR_CONTROL); 653 drm_fs_inode_free(dev->anon_inode); 654 err_free: 655 mutex_destroy(&dev->master_mutex); 656 kfree(dev); 657 return NULL; 658 } 659 EXPORT_SYMBOL(drm_dev_alloc); 660 661 static void drm_dev_release(struct kref *ref) 662 { 663 struct drm_device *dev = container_of(ref, struct drm_device, ref); 664 665 if (drm_core_check_feature(dev, DRIVER_GEM)) 666 drm_gem_destroy(dev); 667 668 drm_legacy_ctxbitmap_cleanup(dev); 669 drm_ht_remove(&dev->map_hash); 670 drm_fs_inode_free(dev->anon_inode); 671 672 drm_minor_free(dev, DRM_MINOR_LEGACY); 673 drm_minor_free(dev, DRM_MINOR_RENDER); 674 drm_minor_free(dev, DRM_MINOR_CONTROL); 675 676 mutex_destroy(&dev->master_mutex); 677 kfree(dev->unique); 678 kfree(dev); 679 } 680 681 /** 682 * drm_dev_ref - Take reference of a DRM device 683 * @dev: device to take reference of or NULL 684 * 685 * This increases the ref-count of @dev by one. You *must* already own a 686 * reference when calling this. Use drm_dev_unref() to drop this reference 687 * again. 688 * 689 * This function never fails. However, this function does not provide *any* 690 * guarantee whether the device is alive or running. It only provides a 691 * reference to the object and the memory associated with it. 692 */ 693 void drm_dev_ref(struct drm_device *dev) 694 { 695 if (dev) 696 kref_get(&dev->ref); 697 } 698 EXPORT_SYMBOL(drm_dev_ref); 699 700 /** 701 * drm_dev_unref - Drop reference of a DRM device 702 * @dev: device to drop reference of or NULL 703 * 704 * This decreases the ref-count of @dev by one. The device is destroyed if the 705 * ref-count drops to zero. 706 */ 707 void drm_dev_unref(struct drm_device *dev) 708 { 709 if (dev) 710 kref_put(&dev->ref, drm_dev_release); 711 } 712 EXPORT_SYMBOL(drm_dev_unref); 713 714 /** 715 * drm_dev_register - Register DRM device 716 * @dev: Device to register 717 * @flags: Flags passed to the driver's .load() function 718 * 719 * Register the DRM device @dev with the system, advertise device to user-space 720 * and start normal device operation. @dev must be allocated via drm_dev_alloc() 721 * previously. Right after drm_dev_register() the driver should call 722 * drm_connector_register_all() to register all connectors in sysfs. This is 723 * a separate call for backward compatibility with drivers still using 724 * the deprecated ->load() callback, where connectors are registered from within 725 * the ->load() callback. 726 * 727 * Never call this twice on any device! 728 * 729 * NOTE: To ensure backward compatibility with existing drivers method this 730 * function calls the ->load() method after registering the device nodes, 731 * creating race conditions. Usage of the ->load() methods is therefore 732 * deprecated, drivers must perform all initialization before calling 733 * drm_dev_register(). 734 * 735 * RETURNS: 736 * 0 on success, negative error code on failure. 737 */ 738 int drm_dev_register(struct drm_device *dev, unsigned long flags) 739 { 740 int ret; 741 742 mutex_lock(&drm_global_mutex); 743 744 ret = drm_minor_register(dev, DRM_MINOR_CONTROL); 745 if (ret) 746 goto err_minors; 747 748 ret = drm_minor_register(dev, DRM_MINOR_RENDER); 749 if (ret) 750 goto err_minors; 751 752 ret = drm_minor_register(dev, DRM_MINOR_LEGACY); 753 if (ret) 754 goto err_minors; 755 756 if (dev->driver->load) { 757 ret = dev->driver->load(dev, flags); 758 if (ret) 759 goto err_minors; 760 } 761 762 ret = 0; 763 goto out_unlock; 764 765 err_minors: 766 drm_minor_unregister(dev, DRM_MINOR_LEGACY); 767 drm_minor_unregister(dev, DRM_MINOR_RENDER); 768 drm_minor_unregister(dev, DRM_MINOR_CONTROL); 769 out_unlock: 770 mutex_unlock(&drm_global_mutex); 771 return ret; 772 } 773 EXPORT_SYMBOL(drm_dev_register); 774 775 /** 776 * drm_dev_unregister - Unregister DRM device 777 * @dev: Device to unregister 778 * 779 * Unregister the DRM device from the system. This does the reverse of 780 * drm_dev_register() but does not deallocate the device. The caller must call 781 * drm_dev_unref() to drop their final reference. 782 * 783 * This should be called first in the device teardown code to make sure 784 * userspace can't access the device instance any more. 785 */ 786 void drm_dev_unregister(struct drm_device *dev) 787 { 788 struct drm_map_list *r_list, *list_temp; 789 790 drm_lastclose(dev); 791 792 if (dev->driver->unload) 793 dev->driver->unload(dev); 794 795 if (dev->agp) 796 drm_pci_agp_destroy(dev); 797 798 drm_vblank_cleanup(dev); 799 800 list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) 801 drm_legacy_rmmap(dev, r_list->map); 802 803 drm_minor_unregister(dev, DRM_MINOR_LEGACY); 804 drm_minor_unregister(dev, DRM_MINOR_RENDER); 805 drm_minor_unregister(dev, DRM_MINOR_CONTROL); 806 } 807 EXPORT_SYMBOL(drm_dev_unregister); 808 809 /** 810 * drm_dev_set_unique - Set the unique name of a DRM device 811 * @dev: device of which to set the unique name 812 * @name: unique name 813 * 814 * Sets the unique name of a DRM device using the specified string. Drivers 815 * can use this at driver probe time if the unique name of the devices they 816 * drive is static. 817 * 818 * Return: 0 on success or a negative error code on failure. 819 */ 820 int drm_dev_set_unique(struct drm_device *dev, const char *name) 821 { 822 kfree(dev->unique); 823 dev->unique = kstrdup(name, GFP_KERNEL); 824 825 return dev->unique ? 0 : -ENOMEM; 826 } 827 EXPORT_SYMBOL(drm_dev_set_unique); 828 829 /* 830 * DRM Core 831 * The DRM core module initializes all global DRM objects and makes them 832 * available to drivers. Once setup, drivers can probe their respective 833 * devices. 834 * Currently, core management includes: 835 * - The "DRM-Global" key/value database 836 * - Global ID management for connectors 837 * - DRM major number allocation 838 * - DRM minor management 839 * - DRM sysfs class 840 * - DRM debugfs root 841 * 842 * Furthermore, the DRM core provides dynamic char-dev lookups. For each 843 * interface registered on a DRM device, you can request minor numbers from DRM 844 * core. DRM core takes care of major-number management and char-dev 845 * registration. A stub ->open() callback forwards any open() requests to the 846 * registered minor. 847 */ 848 849 static int drm_stub_open(struct inode *inode, struct file *filp) 850 { 851 const struct file_operations *new_fops; 852 struct drm_minor *minor; 853 int err; 854 855 DRM_DEBUG("\n"); 856 857 mutex_lock(&drm_global_mutex); 858 minor = drm_minor_acquire(iminor(inode)); 859 if (IS_ERR(minor)) { 860 err = PTR_ERR(minor); 861 goto out_unlock; 862 } 863 864 new_fops = fops_get(minor->dev->driver->fops); 865 if (!new_fops) { 866 err = -ENODEV; 867 goto out_release; 868 } 869 870 replace_fops(filp, new_fops); 871 if (filp->f_op->open) 872 err = filp->f_op->open(inode, filp); 873 else 874 err = 0; 875 876 out_release: 877 drm_minor_release(minor); 878 out_unlock: 879 mutex_unlock(&drm_global_mutex); 880 return err; 881 } 882 883 static const struct file_operations drm_stub_fops = { 884 .owner = THIS_MODULE, 885 .open = drm_stub_open, 886 .llseek = noop_llseek, 887 }; 888 889 static int __init drm_core_init(void) 890 { 891 int ret = -ENOMEM; 892 893 drm_global_init(); 894 drm_connector_ida_init(); 895 idr_init(&drm_minors_idr); 896 897 if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops)) 898 goto err_p1; 899 900 ret = drm_sysfs_init(); 901 if (ret < 0) { 902 printk(KERN_ERR "DRM: Error creating drm class.\n"); 903 goto err_p2; 904 } 905 906 drm_debugfs_root = debugfs_create_dir("dri", NULL); 907 if (!drm_debugfs_root) { 908 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n"); 909 ret = -1; 910 goto err_p3; 911 } 912 913 DRM_INFO("Initialized %s %d.%d.%d %s\n", 914 CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE); 915 return 0; 916 err_p3: 917 drm_sysfs_destroy(); 918 err_p2: 919 unregister_chrdev(DRM_MAJOR, "drm"); 920 921 idr_destroy(&drm_minors_idr); 922 err_p1: 923 return ret; 924 } 925 926 static void __exit drm_core_exit(void) 927 { 928 debugfs_remove(drm_debugfs_root); 929 drm_sysfs_destroy(); 930 931 unregister_chrdev(DRM_MAJOR, "drm"); 932 933 drm_connector_ida_destroy(); 934 idr_destroy(&drm_minors_idr); 935 } 936 937 module_init(drm_core_init); 938 module_exit(drm_core_exit); 939