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 struct drm_map_list *r_list, *list_temp; 125 126 mutex_lock(&dev->struct_mutex); 127 if (dev->driver->master_destroy) 128 dev->driver->master_destroy(dev, master); 129 130 list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) { 131 if (r_list->master == master) { 132 drm_legacy_rmmap_locked(dev, r_list->map); 133 r_list = NULL; 134 } 135 } 136 mutex_unlock(&dev->struct_mutex); 137 138 idr_destroy(&master->magic_map); 139 kfree(master->unique); 140 kfree(master); 141 } 142 143 void drm_master_put(struct drm_master **master) 144 { 145 kref_put(&(*master)->refcount, drm_master_destroy); 146 *master = NULL; 147 } 148 EXPORT_SYMBOL(drm_master_put); 149 150 int drm_setmaster_ioctl(struct drm_device *dev, void *data, 151 struct drm_file *file_priv) 152 { 153 int ret = 0; 154 155 mutex_lock(&dev->master_mutex); 156 if (file_priv->is_master) 157 goto out_unlock; 158 159 if (file_priv->minor->master) { 160 ret = -EINVAL; 161 goto out_unlock; 162 } 163 164 if (!file_priv->master) { 165 ret = -EINVAL; 166 goto out_unlock; 167 } 168 169 if (!file_priv->allowed_master) { 170 ret = drm_new_set_master(dev, file_priv); 171 goto out_unlock; 172 } 173 174 file_priv->minor->master = drm_master_get(file_priv->master); 175 file_priv->is_master = 1; 176 if (dev->driver->master_set) { 177 ret = dev->driver->master_set(dev, file_priv, false); 178 if (unlikely(ret != 0)) { 179 file_priv->is_master = 0; 180 drm_master_put(&file_priv->minor->master); 181 } 182 } 183 184 out_unlock: 185 mutex_unlock(&dev->master_mutex); 186 return ret; 187 } 188 189 int drm_dropmaster_ioctl(struct drm_device *dev, void *data, 190 struct drm_file *file_priv) 191 { 192 int ret = -EINVAL; 193 194 mutex_lock(&dev->master_mutex); 195 if (!file_priv->is_master) 196 goto out_unlock; 197 198 if (!file_priv->minor->master) 199 goto out_unlock; 200 201 ret = 0; 202 if (dev->driver->master_drop) 203 dev->driver->master_drop(dev, file_priv, false); 204 drm_master_put(&file_priv->minor->master); 205 file_priv->is_master = 0; 206 207 out_unlock: 208 mutex_unlock(&dev->master_mutex); 209 return ret; 210 } 211 212 /* 213 * DRM Minors 214 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each 215 * of them is represented by a drm_minor object. Depending on the capabilities 216 * of the device-driver, different interfaces are registered. 217 * 218 * Minors can be accessed via dev->$minor_name. This pointer is either 219 * NULL or a valid drm_minor pointer and stays valid as long as the device is 220 * valid. This means, DRM minors have the same life-time as the underlying 221 * device. However, this doesn't mean that the minor is active. Minors are 222 * registered and unregistered dynamically according to device-state. 223 */ 224 225 static struct drm_minor **drm_minor_get_slot(struct drm_device *dev, 226 unsigned int type) 227 { 228 switch (type) { 229 case DRM_MINOR_LEGACY: 230 return &dev->primary; 231 case DRM_MINOR_RENDER: 232 return &dev->render; 233 case DRM_MINOR_CONTROL: 234 return &dev->control; 235 default: 236 return NULL; 237 } 238 } 239 240 static int drm_minor_alloc(struct drm_device *dev, unsigned int type) 241 { 242 struct drm_minor *minor; 243 unsigned long flags; 244 int r; 245 246 minor = kzalloc(sizeof(*minor), GFP_KERNEL); 247 if (!minor) 248 return -ENOMEM; 249 250 minor->type = type; 251 minor->dev = dev; 252 253 idr_preload(GFP_KERNEL); 254 spin_lock_irqsave(&drm_minor_lock, flags); 255 r = idr_alloc(&drm_minors_idr, 256 NULL, 257 64 * type, 258 64 * (type + 1), 259 GFP_NOWAIT); 260 spin_unlock_irqrestore(&drm_minor_lock, flags); 261 idr_preload_end(); 262 263 if (r < 0) 264 goto err_free; 265 266 minor->index = r; 267 268 minor->kdev = drm_sysfs_minor_alloc(minor); 269 if (IS_ERR(minor->kdev)) { 270 r = PTR_ERR(minor->kdev); 271 goto err_index; 272 } 273 274 *drm_minor_get_slot(dev, type) = minor; 275 return 0; 276 277 err_index: 278 spin_lock_irqsave(&drm_minor_lock, flags); 279 idr_remove(&drm_minors_idr, minor->index); 280 spin_unlock_irqrestore(&drm_minor_lock, flags); 281 err_free: 282 kfree(minor); 283 return r; 284 } 285 286 static void drm_minor_free(struct drm_device *dev, unsigned int type) 287 { 288 struct drm_minor **slot, *minor; 289 unsigned long flags; 290 291 slot = drm_minor_get_slot(dev, type); 292 minor = *slot; 293 if (!minor) 294 return; 295 296 put_device(minor->kdev); 297 298 spin_lock_irqsave(&drm_minor_lock, flags); 299 idr_remove(&drm_minors_idr, minor->index); 300 spin_unlock_irqrestore(&drm_minor_lock, flags); 301 302 kfree(minor); 303 *slot = NULL; 304 } 305 306 static int drm_minor_register(struct drm_device *dev, unsigned int type) 307 { 308 struct drm_minor *minor; 309 unsigned long flags; 310 int ret; 311 312 DRM_DEBUG("\n"); 313 314 minor = *drm_minor_get_slot(dev, type); 315 if (!minor) 316 return 0; 317 318 ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root); 319 if (ret) { 320 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n"); 321 return ret; 322 } 323 324 ret = device_add(minor->kdev); 325 if (ret) 326 goto err_debugfs; 327 328 /* replace NULL with @minor so lookups will succeed from now on */ 329 spin_lock_irqsave(&drm_minor_lock, flags); 330 idr_replace(&drm_minors_idr, minor, minor->index); 331 spin_unlock_irqrestore(&drm_minor_lock, flags); 332 333 DRM_DEBUG("new minor registered %d\n", minor->index); 334 return 0; 335 336 err_debugfs: 337 drm_debugfs_cleanup(minor); 338 return ret; 339 } 340 341 static void drm_minor_unregister(struct drm_device *dev, unsigned int type) 342 { 343 struct drm_minor *minor; 344 unsigned long flags; 345 346 minor = *drm_minor_get_slot(dev, type); 347 if (!minor || !device_is_registered(minor->kdev)) 348 return; 349 350 /* replace @minor with NULL so lookups will fail from now on */ 351 spin_lock_irqsave(&drm_minor_lock, flags); 352 idr_replace(&drm_minors_idr, NULL, minor->index); 353 spin_unlock_irqrestore(&drm_minor_lock, flags); 354 355 device_del(minor->kdev); 356 dev_set_drvdata(minor->kdev, NULL); /* safety belt */ 357 drm_debugfs_cleanup(minor); 358 } 359 360 /** 361 * drm_minor_acquire - Acquire a DRM minor 362 * @minor_id: Minor ID of the DRM-minor 363 * 364 * Looks up the given minor-ID and returns the respective DRM-minor object. The 365 * refence-count of the underlying device is increased so you must release this 366 * object with drm_minor_release(). 367 * 368 * As long as you hold this minor, it is guaranteed that the object and the 369 * minor->dev pointer will stay valid! However, the device may get unplugged and 370 * unregistered while you hold the minor. 371 * 372 * Returns: 373 * Pointer to minor-object with increased device-refcount, or PTR_ERR on 374 * failure. 375 */ 376 struct drm_minor *drm_minor_acquire(unsigned int minor_id) 377 { 378 struct drm_minor *minor; 379 unsigned long flags; 380 381 spin_lock_irqsave(&drm_minor_lock, flags); 382 minor = idr_find(&drm_minors_idr, minor_id); 383 if (minor) 384 drm_dev_ref(minor->dev); 385 spin_unlock_irqrestore(&drm_minor_lock, flags); 386 387 if (!minor) { 388 return ERR_PTR(-ENODEV); 389 } else if (drm_device_is_unplugged(minor->dev)) { 390 drm_dev_unref(minor->dev); 391 return ERR_PTR(-ENODEV); 392 } 393 394 return minor; 395 } 396 397 /** 398 * drm_minor_release - Release DRM minor 399 * @minor: Pointer to DRM minor object 400 * 401 * Release a minor that was previously acquired via drm_minor_acquire(). 402 */ 403 void drm_minor_release(struct drm_minor *minor) 404 { 405 drm_dev_unref(minor->dev); 406 } 407 408 /** 409 * DOC: driver instance overview 410 * 411 * A device instance for a drm driver is represented by struct &drm_device. This 412 * is allocated with drm_dev_alloc(), usually from bus-specific ->probe() 413 * callbacks implemented by the driver. The driver then needs to initialize all 414 * the various subsystems for the drm device like memory management, vblank 415 * handling, modesetting support and intial output configuration plus obviously 416 * initialize all the corresponding hardware bits. An important part of this is 417 * also calling drm_dev_set_unique() to set the userspace-visible unique name of 418 * this device instance. Finally when everything is up and running and ready for 419 * userspace the device instance can be published using drm_dev_register(). 420 * 421 * There is also deprecated support for initalizing device instances using 422 * bus-specific helpers and the ->load() callback. But due to 423 * backwards-compatibility needs the device instance have to be published too 424 * early, which requires unpretty global locking to make safe and is therefore 425 * only support for existing drivers not yet converted to the new scheme. 426 * 427 * When cleaning up a device instance everything needs to be done in reverse: 428 * First unpublish the device instance with drm_dev_unregister(). Then clean up 429 * any other resources allocated at device initialization and drop the driver's 430 * reference to &drm_device using drm_dev_unref(). 431 * 432 * Note that the lifetime rules for &drm_device instance has still a lot of 433 * historical baggage. Hence use the reference counting provided by 434 * drm_dev_ref() and drm_dev_unref() only carefully. 435 * 436 * Also note that embedding of &drm_device is currently not (yet) supported (but 437 * it would be easy to add). Drivers can store driver-private data in the 438 * dev_priv field of &drm_device. 439 */ 440 441 /** 442 * drm_put_dev - Unregister and release a DRM device 443 * @dev: DRM device 444 * 445 * Called at module unload time or when a PCI device is unplugged. 446 * 447 * Cleans up all DRM device, calling drm_lastclose(). 448 * 449 * Note: Use of this function is deprecated. It will eventually go away 450 * completely. Please use drm_dev_unregister() and drm_dev_unref() explicitly 451 * instead to make sure that the device isn't userspace accessible any more 452 * while teardown is in progress, ensuring that userspace can't access an 453 * inconsistent state. 454 */ 455 void drm_put_dev(struct drm_device *dev) 456 { 457 DRM_DEBUG("\n"); 458 459 if (!dev) { 460 DRM_ERROR("cleanup called no dev\n"); 461 return; 462 } 463 464 drm_dev_unregister(dev); 465 drm_dev_unref(dev); 466 } 467 EXPORT_SYMBOL(drm_put_dev); 468 469 void drm_unplug_dev(struct drm_device *dev) 470 { 471 /* for a USB device */ 472 drm_minor_unregister(dev, DRM_MINOR_LEGACY); 473 drm_minor_unregister(dev, DRM_MINOR_RENDER); 474 drm_minor_unregister(dev, DRM_MINOR_CONTROL); 475 476 mutex_lock(&drm_global_mutex); 477 478 drm_device_set_unplugged(dev); 479 480 if (dev->open_count == 0) { 481 drm_put_dev(dev); 482 } 483 mutex_unlock(&drm_global_mutex); 484 } 485 EXPORT_SYMBOL(drm_unplug_dev); 486 487 /* 488 * DRM internal mount 489 * We want to be able to allocate our own "struct address_space" to control 490 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow 491 * stand-alone address_space objects, so we need an underlying inode. As there 492 * is no way to allocate an independent inode easily, we need a fake internal 493 * VFS mount-point. 494 * 495 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free() 496 * frees it again. You are allowed to use iget() and iput() to get references to 497 * the inode. But each drm_fs_inode_new() call must be paired with exactly one 498 * drm_fs_inode_free() call (which does not have to be the last iput()). 499 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it 500 * between multiple inode-users. You could, technically, call 501 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an 502 * iput(), but this way you'd end up with a new vfsmount for each inode. 503 */ 504 505 static int drm_fs_cnt; 506 static struct vfsmount *drm_fs_mnt; 507 508 static const struct dentry_operations drm_fs_dops = { 509 .d_dname = simple_dname, 510 }; 511 512 static const struct super_operations drm_fs_sops = { 513 .statfs = simple_statfs, 514 }; 515 516 static struct dentry *drm_fs_mount(struct file_system_type *fs_type, int flags, 517 const char *dev_name, void *data) 518 { 519 return mount_pseudo(fs_type, 520 "drm:", 521 &drm_fs_sops, 522 &drm_fs_dops, 523 0x010203ff); 524 } 525 526 static struct file_system_type drm_fs_type = { 527 .name = "drm", 528 .owner = THIS_MODULE, 529 .mount = drm_fs_mount, 530 .kill_sb = kill_anon_super, 531 }; 532 533 static struct inode *drm_fs_inode_new(void) 534 { 535 struct inode *inode; 536 int r; 537 538 r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt); 539 if (r < 0) { 540 DRM_ERROR("Cannot mount pseudo fs: %d\n", r); 541 return ERR_PTR(r); 542 } 543 544 inode = alloc_anon_inode(drm_fs_mnt->mnt_sb); 545 if (IS_ERR(inode)) 546 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt); 547 548 return inode; 549 } 550 551 static void drm_fs_inode_free(struct inode *inode) 552 { 553 if (inode) { 554 iput(inode); 555 simple_release_fs(&drm_fs_mnt, &drm_fs_cnt); 556 } 557 } 558 559 /** 560 * drm_dev_alloc - Allocate new DRM device 561 * @driver: DRM driver to allocate device for 562 * @parent: Parent device object 563 * 564 * Allocate and initialize a new DRM device. No device registration is done. 565 * Call drm_dev_register() to advertice the device to user space and register it 566 * with other core subsystems. This should be done last in the device 567 * initialization sequence to make sure userspace can't access an inconsistent 568 * state. 569 * 570 * The initial ref-count of the object is 1. Use drm_dev_ref() and 571 * drm_dev_unref() to take and drop further ref-counts. 572 * 573 * Note that for purely virtual devices @parent can be NULL. 574 * 575 * RETURNS: 576 * Pointer to new DRM device, or NULL if out of memory. 577 */ 578 struct drm_device *drm_dev_alloc(struct drm_driver *driver, 579 struct device *parent) 580 { 581 struct drm_device *dev; 582 int ret; 583 584 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 585 if (!dev) 586 return NULL; 587 588 kref_init(&dev->ref); 589 dev->dev = parent; 590 dev->driver = driver; 591 592 INIT_LIST_HEAD(&dev->filelist); 593 INIT_LIST_HEAD(&dev->ctxlist); 594 INIT_LIST_HEAD(&dev->vmalist); 595 INIT_LIST_HEAD(&dev->maplist); 596 INIT_LIST_HEAD(&dev->vblank_event_list); 597 598 spin_lock_init(&dev->buf_lock); 599 spin_lock_init(&dev->event_lock); 600 mutex_init(&dev->struct_mutex); 601 mutex_init(&dev->ctxlist_mutex); 602 mutex_init(&dev->master_mutex); 603 604 dev->anon_inode = drm_fs_inode_new(); 605 if (IS_ERR(dev->anon_inode)) { 606 ret = PTR_ERR(dev->anon_inode); 607 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret); 608 goto err_free; 609 } 610 611 if (drm_core_check_feature(dev, DRIVER_MODESET)) { 612 ret = drm_minor_alloc(dev, DRM_MINOR_CONTROL); 613 if (ret) 614 goto err_minors; 615 616 WARN_ON(driver->suspend || driver->resume); 617 } 618 619 if (drm_core_check_feature(dev, DRIVER_RENDER)) { 620 ret = drm_minor_alloc(dev, DRM_MINOR_RENDER); 621 if (ret) 622 goto err_minors; 623 } 624 625 ret = drm_minor_alloc(dev, DRM_MINOR_LEGACY); 626 if (ret) 627 goto err_minors; 628 629 if (drm_ht_create(&dev->map_hash, 12)) 630 goto err_minors; 631 632 drm_legacy_ctxbitmap_init(dev); 633 634 if (drm_core_check_feature(dev, DRIVER_GEM)) { 635 ret = drm_gem_init(dev); 636 if (ret) { 637 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n"); 638 goto err_ctxbitmap; 639 } 640 } 641 642 if (parent) { 643 ret = drm_dev_set_unique(dev, dev_name(parent)); 644 if (ret) 645 goto err_setunique; 646 } 647 648 return dev; 649 650 err_setunique: 651 if (drm_core_check_feature(dev, DRIVER_GEM)) 652 drm_gem_destroy(dev); 653 err_ctxbitmap: 654 drm_legacy_ctxbitmap_cleanup(dev); 655 drm_ht_remove(&dev->map_hash); 656 err_minors: 657 drm_minor_free(dev, DRM_MINOR_LEGACY); 658 drm_minor_free(dev, DRM_MINOR_RENDER); 659 drm_minor_free(dev, DRM_MINOR_CONTROL); 660 drm_fs_inode_free(dev->anon_inode); 661 err_free: 662 mutex_destroy(&dev->master_mutex); 663 kfree(dev); 664 return NULL; 665 } 666 EXPORT_SYMBOL(drm_dev_alloc); 667 668 static void drm_dev_release(struct kref *ref) 669 { 670 struct drm_device *dev = container_of(ref, struct drm_device, ref); 671 672 if (drm_core_check_feature(dev, DRIVER_GEM)) 673 drm_gem_destroy(dev); 674 675 drm_legacy_ctxbitmap_cleanup(dev); 676 drm_ht_remove(&dev->map_hash); 677 drm_fs_inode_free(dev->anon_inode); 678 679 drm_minor_free(dev, DRM_MINOR_LEGACY); 680 drm_minor_free(dev, DRM_MINOR_RENDER); 681 drm_minor_free(dev, DRM_MINOR_CONTROL); 682 683 mutex_destroy(&dev->master_mutex); 684 kfree(dev->unique); 685 kfree(dev); 686 } 687 688 /** 689 * drm_dev_ref - Take reference of a DRM device 690 * @dev: device to take reference of or NULL 691 * 692 * This increases the ref-count of @dev by one. You *must* already own a 693 * reference when calling this. Use drm_dev_unref() to drop this reference 694 * again. 695 * 696 * This function never fails. However, this function does not provide *any* 697 * guarantee whether the device is alive or running. It only provides a 698 * reference to the object and the memory associated with it. 699 */ 700 void drm_dev_ref(struct drm_device *dev) 701 { 702 if (dev) 703 kref_get(&dev->ref); 704 } 705 EXPORT_SYMBOL(drm_dev_ref); 706 707 /** 708 * drm_dev_unref - Drop reference of a DRM device 709 * @dev: device to drop reference of or NULL 710 * 711 * This decreases the ref-count of @dev by one. The device is destroyed if the 712 * ref-count drops to zero. 713 */ 714 void drm_dev_unref(struct drm_device *dev) 715 { 716 if (dev) 717 kref_put(&dev->ref, drm_dev_release); 718 } 719 EXPORT_SYMBOL(drm_dev_unref); 720 721 /** 722 * drm_dev_register - Register DRM device 723 * @dev: Device to register 724 * @flags: Flags passed to the driver's .load() function 725 * 726 * Register the DRM device @dev with the system, advertise device to user-space 727 * and start normal device operation. @dev must be allocated via drm_dev_alloc() 728 * previously. Right after drm_dev_register() the driver should call 729 * drm_connector_register_all() to register all connectors in sysfs. This is 730 * a separate call for backward compatibility with drivers still using 731 * the deprecated ->load() callback, where connectors are registered from within 732 * the ->load() callback. 733 * 734 * Never call this twice on any device! 735 * 736 * NOTE: To ensure backward compatibility with existing drivers method this 737 * function calls the ->load() method after registering the device nodes, 738 * creating race conditions. Usage of the ->load() methods is therefore 739 * deprecated, drivers must perform all initialization before calling 740 * drm_dev_register(). 741 * 742 * RETURNS: 743 * 0 on success, negative error code on failure. 744 */ 745 int drm_dev_register(struct drm_device *dev, unsigned long flags) 746 { 747 int ret; 748 749 mutex_lock(&drm_global_mutex); 750 751 ret = drm_minor_register(dev, DRM_MINOR_CONTROL); 752 if (ret) 753 goto err_minors; 754 755 ret = drm_minor_register(dev, DRM_MINOR_RENDER); 756 if (ret) 757 goto err_minors; 758 759 ret = drm_minor_register(dev, DRM_MINOR_LEGACY); 760 if (ret) 761 goto err_minors; 762 763 if (dev->driver->load) { 764 ret = dev->driver->load(dev, flags); 765 if (ret) 766 goto err_minors; 767 } 768 769 ret = 0; 770 goto out_unlock; 771 772 err_minors: 773 drm_minor_unregister(dev, DRM_MINOR_LEGACY); 774 drm_minor_unregister(dev, DRM_MINOR_RENDER); 775 drm_minor_unregister(dev, DRM_MINOR_CONTROL); 776 out_unlock: 777 mutex_unlock(&drm_global_mutex); 778 return ret; 779 } 780 EXPORT_SYMBOL(drm_dev_register); 781 782 /** 783 * drm_dev_unregister - Unregister DRM device 784 * @dev: Device to unregister 785 * 786 * Unregister the DRM device from the system. This does the reverse of 787 * drm_dev_register() but does not deallocate the device. The caller must call 788 * drm_dev_unref() to drop their final reference. 789 * 790 * This should be called first in the device teardown code to make sure 791 * userspace can't access the device instance any more. 792 */ 793 void drm_dev_unregister(struct drm_device *dev) 794 { 795 struct drm_map_list *r_list, *list_temp; 796 797 drm_lastclose(dev); 798 799 if (dev->driver->unload) 800 dev->driver->unload(dev); 801 802 if (dev->agp) 803 drm_pci_agp_destroy(dev); 804 805 drm_vblank_cleanup(dev); 806 807 list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) 808 drm_legacy_rmmap(dev, r_list->map); 809 810 drm_minor_unregister(dev, DRM_MINOR_LEGACY); 811 drm_minor_unregister(dev, DRM_MINOR_RENDER); 812 drm_minor_unregister(dev, DRM_MINOR_CONTROL); 813 } 814 EXPORT_SYMBOL(drm_dev_unregister); 815 816 /** 817 * drm_dev_set_unique - Set the unique name of a DRM device 818 * @dev: device of which to set the unique name 819 * @name: unique name 820 * 821 * Sets the unique name of a DRM device using the specified string. Drivers 822 * can use this at driver probe time if the unique name of the devices they 823 * drive is static. 824 * 825 * Return: 0 on success or a negative error code on failure. 826 */ 827 int drm_dev_set_unique(struct drm_device *dev, const char *name) 828 { 829 kfree(dev->unique); 830 dev->unique = kstrdup(name, GFP_KERNEL); 831 832 return dev->unique ? 0 : -ENOMEM; 833 } 834 EXPORT_SYMBOL(drm_dev_set_unique); 835 836 /* 837 * DRM Core 838 * The DRM core module initializes all global DRM objects and makes them 839 * available to drivers. Once setup, drivers can probe their respective 840 * devices. 841 * Currently, core management includes: 842 * - The "DRM-Global" key/value database 843 * - Global ID management for connectors 844 * - DRM major number allocation 845 * - DRM minor management 846 * - DRM sysfs class 847 * - DRM debugfs root 848 * 849 * Furthermore, the DRM core provides dynamic char-dev lookups. For each 850 * interface registered on a DRM device, you can request minor numbers from DRM 851 * core. DRM core takes care of major-number management and char-dev 852 * registration. A stub ->open() callback forwards any open() requests to the 853 * registered minor. 854 */ 855 856 static int drm_stub_open(struct inode *inode, struct file *filp) 857 { 858 const struct file_operations *new_fops; 859 struct drm_minor *minor; 860 int err; 861 862 DRM_DEBUG("\n"); 863 864 mutex_lock(&drm_global_mutex); 865 minor = drm_minor_acquire(iminor(inode)); 866 if (IS_ERR(minor)) { 867 err = PTR_ERR(minor); 868 goto out_unlock; 869 } 870 871 new_fops = fops_get(minor->dev->driver->fops); 872 if (!new_fops) { 873 err = -ENODEV; 874 goto out_release; 875 } 876 877 replace_fops(filp, new_fops); 878 if (filp->f_op->open) 879 err = filp->f_op->open(inode, filp); 880 else 881 err = 0; 882 883 out_release: 884 drm_minor_release(minor); 885 out_unlock: 886 mutex_unlock(&drm_global_mutex); 887 return err; 888 } 889 890 static const struct file_operations drm_stub_fops = { 891 .owner = THIS_MODULE, 892 .open = drm_stub_open, 893 .llseek = noop_llseek, 894 }; 895 896 static int __init drm_core_init(void) 897 { 898 int ret = -ENOMEM; 899 900 drm_global_init(); 901 drm_connector_ida_init(); 902 idr_init(&drm_minors_idr); 903 904 if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops)) 905 goto err_p1; 906 907 ret = drm_sysfs_init(); 908 if (ret < 0) { 909 printk(KERN_ERR "DRM: Error creating drm class.\n"); 910 goto err_p2; 911 } 912 913 drm_debugfs_root = debugfs_create_dir("dri", NULL); 914 if (!drm_debugfs_root) { 915 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n"); 916 ret = -1; 917 goto err_p3; 918 } 919 920 DRM_INFO("Initialized %s %d.%d.%d %s\n", 921 CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE); 922 return 0; 923 err_p3: 924 drm_sysfs_destroy(); 925 err_p2: 926 unregister_chrdev(DRM_MAJOR, "drm"); 927 928 idr_destroy(&drm_minors_idr); 929 err_p1: 930 return ret; 931 } 932 933 static void __exit drm_core_exit(void) 934 { 935 debugfs_remove(drm_debugfs_root); 936 drm_sysfs_destroy(); 937 938 unregister_chrdev(DRM_MAJOR, "drm"); 939 940 drm_connector_ida_destroy(); 941 idr_destroy(&drm_minors_idr); 942 } 943 944 module_init(drm_core_init); 945 module_exit(drm_core_exit); 946