1 /* 2 * Copyright © 2008 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 * 23 * Authors: 24 * Eric Anholt <eric@anholt.net> 25 * 26 */ 27 /*- 28 * Copyright (c) 2011 The FreeBSD Foundation 29 * All rights reserved. 30 * 31 * This software was developed by Konstantin Belousov under sponsorship from 32 * the FreeBSD Foundation. 33 * 34 * Redistribution and use in source and binary forms, with or without 35 * modification, are permitted provided that the following conditions 36 * are met: 37 * 1. Redistributions of source code must retain the above copyright 38 * notice, this list of conditions and the following disclaimer. 39 * 2. Redistributions in binary form must reproduce the above copyright 40 * notice, this list of conditions and the following disclaimer in the 41 * documentation and/or other materials provided with the distribution. 42 * 43 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 44 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 45 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 46 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 47 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 48 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 49 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 50 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 51 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 52 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 53 * SUCH DAMAGE. 54 */ 55 56 #include "opt_vm.h" 57 58 #include <sys/param.h> 59 #include <sys/systm.h> 60 #include <sys/limits.h> 61 #include <sys/lock.h> 62 #include <sys/mutex.h> 63 #include <sys/conf.h> 64 65 #include <vm/vm.h> 66 #include <vm/vm_page.h> 67 68 #include <linux/types.h> 69 #include <linux/mm.h> 70 #include <linux/module.h> 71 #include <drm/drmP.h> 72 #include <drm/drm_vma_manager.h> 73 #include <drm/drm_gem.h> 74 #include "drm_internal.h" 75 76 /** @file drm_gem.c 77 * 78 * This file provides some of the base ioctls and library routines for 79 * the graphics memory manager implemented by each device driver. 80 * 81 * Because various devices have different requirements in terms of 82 * synchronization and migration strategies, implementing that is left up to 83 * the driver, and all that the general API provides should be generic -- 84 * allocating objects, reading/writing data with the cpu, freeing objects. 85 * Even there, platform-dependent optimizations for reading/writing data with 86 * the CPU mean we'll likely hook those out to driver-specific calls. However, 87 * the DRI2 implementation wants to have at least allocate/mmap be generic. 88 * 89 * The goal was to have swap-backed object allocation managed through 90 * struct file. However, file descriptors as handles to a struct file have 91 * two major failings: 92 * - Process limits prevent more than 1024 or so being used at a time by 93 * default. 94 * - Inability to allocate high fds will aggravate the X Server's select() 95 * handling, and likely that of many GL client applications as well. 96 * 97 * This led to a plan of using our own integer IDs (called handles, following 98 * DRM terminology) to mimic fds, and implement the fd syscalls we need as 99 * ioctls. The objects themselves will still include the struct file so 100 * that we can transition to fds if the required kernel infrastructure shows 101 * up at a later date, and as our interface with shmfs for memory allocation. 102 */ 103 104 /* 105 * We make up offsets for buffer objects so we can recognize them at 106 * mmap time. 107 */ 108 109 /* pgoff in mmap is an unsigned long, so we need to make sure that 110 * the faked up offset will fit 111 */ 112 113 #if BITS_PER_LONG == 64 114 #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1) 115 #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16) 116 #else 117 #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1) 118 #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16) 119 #endif 120 121 /** 122 * drm_gem_init - Initialize the GEM device fields 123 * @dev: drm_devic structure to initialize 124 */ 125 int 126 drm_gem_init(struct drm_device *dev) 127 { 128 struct drm_gem_mm *mm; 129 130 lockinit(&dev->object_name_lock, "objnam", 0, LK_CANRECURSE); 131 idr_init(&dev->object_name_idr); 132 133 mm = kzalloc(sizeof(struct drm_gem_mm), GFP_KERNEL); 134 if (!mm) { 135 DRM_ERROR("out of memory\n"); 136 return -ENOMEM; 137 } 138 139 dev->mm_private = mm; 140 141 if (drm_ht_create(&mm->offset_hash, 12)) { 142 kfree(mm); 143 return -ENOMEM; 144 } 145 146 mm->idxunr = new_unrhdr(0, DRM_GEM_MAX_IDX, NULL); 147 drm_mm_init(&mm->offset_manager, DRM_FILE_PAGE_OFFSET_START, 148 DRM_FILE_PAGE_OFFSET_SIZE); 149 drm_vma_offset_manager_init(&mm->vma_manager, 150 DRM_FILE_PAGE_OFFSET_START, 151 DRM_FILE_PAGE_OFFSET_SIZE); 152 153 return 0; 154 } 155 156 void 157 drm_gem_destroy(struct drm_device *dev) 158 { 159 struct drm_gem_mm *mm = dev->mm_private; 160 161 drm_mm_takedown(&mm->offset_manager); 162 drm_ht_remove(&mm->offset_hash); 163 164 drm_vma_offset_manager_destroy(&mm->vma_manager); 165 delete_unrhdr(mm->idxunr); 166 kfree(mm); 167 dev->mm_private = NULL; 168 } 169 170 /** 171 * Initialize an already allocated GEM object of the specified size with 172 * shmfs backing store. 173 */ 174 int drm_gem_object_init(struct drm_device *dev, 175 struct drm_gem_object *obj, size_t size) 176 { 177 drm_gem_private_object_init(dev, obj, size); 178 179 obj->vm_obj = default_pager_alloc(NULL, size, 180 VM_PROT_READ | VM_PROT_WRITE, 0); 181 182 return 0; 183 } 184 EXPORT_SYMBOL(drm_gem_object_init); 185 186 /** 187 * drm_gem_object_init - initialize an allocated private GEM object 188 * @dev: drm_device the object should be initialized for 189 * @obj: drm_gem_object to initialize 190 * @size: object size 191 * 192 * Initialize an already allocated GEM object of the specified size with 193 * no GEM provided backing store. Instead the caller is responsible for 194 * backing the object and handling it. 195 */ 196 void drm_gem_private_object_init(struct drm_device *dev, 197 struct drm_gem_object *obj, size_t size) 198 { 199 BUG_ON((size & (PAGE_SIZE - 1)) != 0); 200 201 obj->dev = dev; 202 obj->vm_obj = NULL; 203 204 kref_init(&obj->refcount); 205 obj->handle_count = 0; 206 obj->size = size; 207 drm_vma_node_reset(&obj->vma_node); 208 } 209 EXPORT_SYMBOL(drm_gem_private_object_init); 210 211 static void 212 drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp) 213 { 214 #if 0 215 if (obj->import_attach) { 216 drm_prime_remove_buf_handle(&filp->prime, 217 obj->import_attach->dmabuf); 218 } 219 if (obj->export_dma_buf) { 220 drm_prime_remove_buf_handle(&filp->prime, 221 obj->export_dma_buf); 222 } 223 #endif 224 } 225 226 static void drm_gem_object_ref_bug(struct kref *list_kref) 227 { 228 BUG(); 229 } 230 231 /** 232 * drm_gem_object_free - release resources bound to userspace handles 233 * @obj: GEM object to clean up. 234 * 235 * Called after the last handle to the object has been closed 236 * 237 * Removes any name for the object. Note that this must be 238 * called before drm_gem_object_free or we'll be touching 239 * freed memory 240 */ 241 static void drm_gem_object_handle_free(struct drm_gem_object *obj) 242 { 243 struct drm_device *dev = obj->dev; 244 245 /* Remove any name for this object */ 246 if (obj->name) { 247 idr_remove(&dev->object_name_idr, obj->name); 248 obj->name = 0; 249 /* 250 * The object name held a reference to this object, drop 251 * that now. 252 * 253 * This cannot be the last reference, since the handle holds one too. 254 */ 255 kref_put(&obj->refcount, drm_gem_object_ref_bug); 256 } 257 } 258 259 #if 0 260 static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj) 261 { 262 /* Unbreak the reference cycle if we have an exported dma_buf. */ 263 if (obj->dma_buf) { 264 dma_buf_put(obj->dma_buf); 265 obj->dma_buf = NULL; 266 } 267 } 268 #endif 269 270 static void 271 drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) 272 { 273 if (WARN_ON(obj->handle_count == 0)) 274 return; 275 276 /* 277 * Must bump handle count first as this may be the last 278 * ref, in which case the object would disappear before we 279 * checked for a name 280 */ 281 282 mutex_lock(&obj->dev->object_name_lock); 283 if (--obj->handle_count == 0) 284 drm_gem_object_handle_free(obj); 285 mutex_unlock(&obj->dev->object_name_lock); 286 287 drm_gem_object_unreference_unlocked(obj); 288 } 289 290 /* 291 * Called at device close to release the file's 292 * handle references on objects. 293 */ 294 static int 295 drm_gem_object_release_handle(int id, void *ptr, void *data) 296 { 297 struct drm_file *file_priv = data; 298 struct drm_gem_object *obj = ptr; 299 struct drm_device *dev = obj->dev; 300 301 drm_gem_remove_prime_handles(obj, file_priv); 302 303 if (dev->driver->gem_close_object) 304 dev->driver->gem_close_object(obj, file_priv); 305 306 drm_gem_object_handle_unreference_unlocked(obj); 307 308 return 0; 309 } 310 311 /** 312 * drm_gem_handle_delete - deletes the given file-private handle 313 * @filp: drm file-private structure to use for the handle look up 314 * @handle: userspace handle to delete 315 * 316 * Removes the GEM handle from the @filp lookup table which has been added with 317 * drm_gem_handle_create(). If this is the last handle also cleans up linked 318 * resources like GEM names. 319 */ 320 int 321 drm_gem_handle_delete(struct drm_file *filp, u32 handle) 322 { 323 struct drm_device *dev; 324 struct drm_gem_object *obj; 325 326 /* This is gross. The idr system doesn't let us try a delete and 327 * return an error code. It just spews if you fail at deleting. 328 * So, we have to grab a lock around finding the object and then 329 * doing the delete on it and dropping the refcount, or the user 330 * could race us to double-decrement the refcount and cause a 331 * use-after-free later. Given the frequency of our handle lookups, 332 * we may want to use ida for number allocation and a hash table 333 * for the pointers, anyway. 334 */ 335 lockmgr(&filp->table_lock, LK_EXCLUSIVE); 336 337 /* Check if we currently have a reference on the object */ 338 obj = idr_find(&filp->object_idr, handle); 339 if (obj == NULL) { 340 lockmgr(&filp->table_lock, LK_RELEASE); 341 return -EINVAL; 342 } 343 dev = obj->dev; 344 345 /* Release reference and decrement refcount. */ 346 idr_remove(&filp->object_idr, handle); 347 lockmgr(&filp->table_lock, LK_RELEASE); 348 349 drm_gem_remove_prime_handles(obj, filp); 350 351 if (dev->driver->gem_close_object) 352 dev->driver->gem_close_object(obj, filp); 353 drm_gem_object_handle_unreference_unlocked(obj); 354 355 return 0; 356 } 357 EXPORT_SYMBOL(drm_gem_handle_delete); 358 359 /** 360 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers 361 * @file: drm file-private structure to remove the dumb handle from 362 * @dev: corresponding drm_device 363 * @handle: the dumb handle to remove 364 * 365 * This implements the ->dumb_destroy kms driver callback for drivers which use 366 * gem to manage their backing storage. 367 */ 368 int drm_gem_dumb_destroy(struct drm_file *file, 369 struct drm_device *dev, 370 uint32_t handle) 371 { 372 return drm_gem_handle_delete(file, handle); 373 } 374 EXPORT_SYMBOL(drm_gem_dumb_destroy); 375 376 /** 377 * drm_gem_handle_create_tail - internal functions to create a handle 378 * @file_priv: drm file-private structure to register the handle for 379 * @obj: object to register 380 * @handlep: pointer to return the created handle to the caller 381 * 382 * This expects the dev->object_name_lock to be held already and will drop it 383 * before returning. Used to avoid races in establishing new handles when 384 * importing an object from either an flink name or a dma-buf. 385 * 386 * Handles must be release again through drm_gem_handle_delete(). This is done 387 * when userspace closes @file_priv for all attached handles, or through the 388 * GEM_CLOSE ioctl for individual handles. 389 */ 390 int 391 drm_gem_handle_create_tail(struct drm_file *file_priv, 392 struct drm_gem_object *obj, 393 u32 *handlep) 394 { 395 struct drm_device *dev = obj->dev; 396 int ret; 397 398 *handlep = 0; /* whack gcc warning */ 399 WARN_ON(!mutex_is_locked(&dev->object_name_lock)); 400 401 /* 402 * Get the user-visible handle using idr. Preload and perform 403 * allocation under our spinlock. 404 */ 405 idr_preload(GFP_KERNEL); 406 lockmgr(&file_priv->table_lock, LK_EXCLUSIVE); 407 408 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT); 409 drm_gem_object_reference(obj); 410 obj->handle_count++; 411 lockmgr(&file_priv->table_lock, LK_RELEASE); 412 idr_preload_end(); 413 mutex_unlock(&dev->object_name_lock); 414 if (ret < 0) { 415 drm_gem_object_handle_unreference_unlocked(obj); 416 return ret; 417 } 418 *handlep = ret; 419 420 #if 0 421 ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp); 422 if (ret) { 423 drm_gem_handle_delete(file_priv, *handlep); 424 return ret; 425 } 426 #endif 427 428 if (dev->driver->gem_open_object) { 429 ret = dev->driver->gem_open_object(obj, file_priv); 430 if (ret) { 431 drm_gem_handle_delete(file_priv, *handlep); 432 return ret; 433 } 434 } 435 436 return 0; 437 } 438 439 /** 440 * drm_gem_handle_create - create a gem handle for an object 441 * @file_priv: drm file-private structure to register the handle for 442 * @obj: object to register 443 * @handlep: pionter to return the created handle to the caller 444 * 445 * Create a handle for this object. This adds a handle reference 446 * to the object, which includes a regular reference count. Callers 447 * will likely want to dereference the object afterwards. 448 */ 449 int drm_gem_handle_create(struct drm_file *file_priv, 450 struct drm_gem_object *obj, 451 u32 *handlep) 452 { 453 mutex_lock(&obj->dev->object_name_lock); 454 455 return drm_gem_handle_create_tail(file_priv, obj, handlep); 456 } 457 EXPORT_SYMBOL(drm_gem_handle_create); 458 459 /** 460 * drm_gem_free_mmap_offset - release a fake mmap offset for an object 461 * @obj: obj in question 462 * 463 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset(). 464 * 465 * Note that drm_gem_object_release() already calls this function, so drivers 466 * don't have to take care of releasing the mmap offset themselves when freeing 467 * the GEM object. 468 */ 469 void 470 drm_gem_free_mmap_offset(struct drm_gem_object *obj) 471 { 472 struct drm_device *dev = obj->dev; 473 struct drm_gem_mm *mm = dev->mm_private; 474 struct drm_hash_item *list; 475 476 if (!obj->on_map) 477 return; 478 list = &obj->map_list; 479 480 drm_ht_remove_item(&mm->offset_hash, list); 481 free_unr(mm->idxunr, list->key); 482 obj->on_map = false; 483 484 drm_vma_offset_remove(&mm->vma_manager, &obj->vma_node); 485 } 486 EXPORT_SYMBOL(drm_gem_free_mmap_offset); 487 488 /** 489 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object 490 * @obj: obj in question 491 * @size: the virtual size 492 * 493 * GEM memory mapping works by handing back to userspace a fake mmap offset 494 * it can use in a subsequent mmap(2) call. The DRM core code then looks 495 * up the object based on the offset and sets up the various memory mapping 496 * structures. 497 * 498 * This routine allocates and attaches a fake offset for @obj, in cases where 499 * the virtual size differs from the physical size (ie. obj->size). Otherwise 500 * just use drm_gem_create_mmap_offset(). 501 * 502 * This function is idempotent and handles an already allocated mmap offset 503 * transparently. Drivers do not need to check for this case. 504 */ 505 int 506 drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size) 507 { 508 struct drm_device *dev = obj->dev; 509 struct drm_gem_mm *mm = dev->mm_private; 510 int ret = 0; 511 512 if (obj->on_map) 513 return (0); 514 515 obj->map_list.key = alloc_unr(mm->idxunr); 516 ret = drm_ht_insert_item(&mm->offset_hash, &obj->map_list); 517 if (ret != 0) { 518 DRM_ERROR("failed to add to map hash\n"); 519 free_unr(mm->idxunr, obj->map_list.key); 520 return (ret); 521 } 522 obj->on_map = true; 523 return 0; 524 525 return drm_vma_offset_add(&mm->vma_manager, &obj->vma_node, 526 size / PAGE_SIZE); 527 } 528 EXPORT_SYMBOL(drm_gem_create_mmap_offset_size); 529 530 /** 531 * drm_gem_create_mmap_offset - create a fake mmap offset for an object 532 * @obj: obj in question 533 * 534 * GEM memory mapping works by handing back to userspace a fake mmap offset 535 * it can use in a subsequent mmap(2) call. The DRM core code then looks 536 * up the object based on the offset and sets up the various memory mapping 537 * structures. 538 * 539 * This routine allocates and attaches a fake offset for @obj. 540 * 541 * Drivers can call drm_gem_free_mmap_offset() before freeing @obj to release 542 * the fake offset again. 543 */ 544 int drm_gem_create_mmap_offset(struct drm_gem_object *obj) 545 { 546 return drm_gem_create_mmap_offset_size(obj, obj->size); 547 } 548 EXPORT_SYMBOL(drm_gem_create_mmap_offset); 549 550 /** 551 * drm_gem_object_lookup - look up a GEM object from it's handle 552 * @dev: DRM device 553 * @filp: DRM file private date 554 * @handle: userspace handle 555 * 556 * Returns: 557 * 558 * A reference to the object named by the handle if such exists on @filp, NULL 559 * otherwise. 560 */ 561 struct drm_gem_object * 562 drm_gem_object_lookup(struct drm_file *filp, u32 handle) 563 { 564 struct drm_gem_object *obj; 565 566 lockmgr(&filp->table_lock, LK_EXCLUSIVE); 567 568 /* Check if we currently have a reference on the object */ 569 obj = idr_find(&filp->object_idr, handle); 570 if (obj == NULL) { 571 lockmgr(&filp->table_lock, LK_RELEASE); 572 return NULL; 573 } 574 575 drm_gem_object_reference(obj); 576 577 lockmgr(&filp->table_lock, LK_RELEASE); 578 579 return obj; 580 } 581 EXPORT_SYMBOL(drm_gem_object_lookup); 582 583 /** 584 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl 585 * @dev: drm_device 586 * @data: ioctl data 587 * @file_priv: drm file-private structure 588 * 589 * Releases the handle to an mm object. 590 */ 591 int 592 drm_gem_close_ioctl(struct drm_device *dev, void *data, 593 struct drm_file *file_priv) 594 { 595 struct drm_gem_close *args = data; 596 int ret; 597 598 if (!drm_core_check_feature(dev, DRIVER_GEM)) 599 return -ENODEV; 600 601 ret = drm_gem_handle_delete(file_priv, args->handle); 602 603 return ret; 604 } 605 606 /** 607 * Create a global name for an object, returning the name. 608 * 609 * Note that the name does not hold a reference; when the object 610 * is freed, the name goes away. 611 */ 612 int 613 drm_gem_flink_ioctl(struct drm_device *dev, void *data, 614 struct drm_file *file_priv) 615 { 616 struct drm_gem_flink *args = data; 617 struct drm_gem_object *obj; 618 int ret; 619 620 if (!drm_core_check_feature(dev, DRIVER_GEM)) 621 return -ENODEV; 622 623 obj = drm_gem_object_lookup(file_priv, args->handle); 624 if (obj == NULL) 625 return -ENOENT; 626 627 idr_preload(GFP_KERNEL); 628 lockmgr(&dev->object_name_lock, LK_EXCLUSIVE); 629 /* prevent races with concurrent gem_close. */ 630 if (obj->handle_count == 0) { 631 ret = -ENOENT; 632 goto err; 633 } 634 635 if (!obj->name) { 636 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT); 637 if (ret < 0) 638 goto err; 639 640 obj->name = ret; 641 642 /* Allocate a reference for the name table. */ 643 drm_gem_object_reference(obj); 644 } 645 646 args->name = (uint64_t) obj->name; 647 ret = 0; 648 649 err: 650 lockmgr(&dev->object_name_lock, LK_RELEASE); 651 idr_preload_end(); 652 drm_gem_object_unreference_unlocked(obj); 653 return ret; 654 } 655 656 /** 657 * drm_gem_open - implementation of the GEM_OPEN ioctl 658 * @dev: drm_device 659 * @data: ioctl data 660 * @file_priv: drm file-private structure 661 * 662 * Open an object using the global name, returning a handle and the size. 663 * 664 * This handle (of course) holds a reference to the object, so the object 665 * will not go away until the handle is deleted. 666 */ 667 int 668 drm_gem_open_ioctl(struct drm_device *dev, void *data, 669 struct drm_file *file_priv) 670 { 671 struct drm_gem_open *args = data; 672 struct drm_gem_object *obj; 673 int ret; 674 u32 handle; 675 676 if (!drm_core_check_feature(dev, DRIVER_GEM)) 677 return -ENODEV; 678 679 lockmgr(&dev->object_name_lock, LK_EXCLUSIVE); 680 obj = idr_find(&dev->object_name_idr, (int) args->name); 681 if (obj) 682 drm_gem_object_reference(obj); 683 lockmgr(&dev->object_name_lock, LK_RELEASE); 684 if (!obj) 685 return -ENOENT; 686 687 ret = drm_gem_handle_create(file_priv, obj, &handle); 688 drm_gem_object_unreference_unlocked(obj); 689 if (ret) 690 return ret; 691 692 args->handle = handle; 693 args->size = obj->size; 694 695 return 0; 696 } 697 698 /** 699 * gem_gem_open - initalizes GEM file-private structures at devnode open time 700 * @dev: drm_device which is being opened by userspace 701 * @file_private: drm file-private structure to set up 702 * 703 * Called at device open time, sets up the structure for handling refcounting 704 * of mm objects. 705 */ 706 void 707 drm_gem_open(struct drm_device *dev, struct drm_file *file_private) 708 { 709 idr_init(&file_private->object_idr); 710 lockinit(&file_private->table_lock, "fptab", 0, LK_CANRECURSE); 711 } 712 713 /** 714 * drm_gem_release - release file-private GEM resources 715 * @dev: drm_device which is being closed by userspace 716 * @file_private: drm file-private structure to clean up 717 * 718 * Called at close time when the filp is going away. 719 * 720 * Releases any remaining references on objects by this filp. 721 */ 722 void 723 drm_gem_release(struct drm_device *dev, struct drm_file *file_private) 724 { 725 idr_for_each(&file_private->object_idr, 726 &drm_gem_object_release_handle, file_private); 727 idr_destroy(&file_private->object_idr); 728 } 729 730 /** 731 * drm_gem_object_release - release GEM buffer object resources 732 * @obj: GEM buffer object 733 * 734 * This releases any structures and resources used by @obj and is the invers of 735 * drm_gem_object_init(). 736 */ 737 void 738 drm_gem_object_release(struct drm_gem_object *obj) 739 { 740 741 /* 742 * obj->vm_obj can be NULL for private gem objects. 743 */ 744 vm_object_deallocate(obj->vm_obj); 745 } 746 EXPORT_SYMBOL(drm_gem_object_release); 747 748 /** 749 * drm_gem_object_free - free a GEM object 750 * @kref: kref of the object to free 751 * 752 * Called after the last reference to the object has been lost. 753 * Must be called holding struct_ mutex 754 * 755 * Frees the object 756 */ 757 void 758 drm_gem_object_free(struct kref *kref) 759 { 760 struct drm_gem_object *obj = 761 container_of(kref, struct drm_gem_object, refcount); 762 struct drm_device *dev = obj->dev; 763 764 WARN_ON(!mutex_is_locked(&dev->struct_mutex)); 765 766 if (dev->driver->gem_free_object != NULL) 767 dev->driver->gem_free_object(obj); 768 } 769 EXPORT_SYMBOL(drm_gem_object_free); 770 771 static struct drm_gem_object * 772 drm_gem_object_from_offset(struct drm_device *dev, vm_ooffset_t offset) 773 { 774 struct drm_gem_object *obj; 775 struct drm_gem_mm *mm = dev->mm_private; 776 struct drm_hash_item *hash; 777 778 if ((offset & DRM_GEM_MAPPING_MASK) != DRM_GEM_MAPPING_KEY) 779 return (NULL); 780 offset &= ~DRM_GEM_MAPPING_KEY; 781 782 if (drm_ht_find_item(&mm->offset_hash, DRM_GEM_MAPPING_IDX(offset), 783 &hash) != 0) { 784 return (NULL); 785 } 786 obj = container_of(hash, struct drm_gem_object, map_list); 787 return (obj); 788 } 789 790 int 791 drm_gem_mmap_single(struct drm_device *dev, vm_ooffset_t *offset, vm_size_t size, 792 struct vm_object **obj_res, int nprot) 793 { 794 struct drm_gem_object *gem_obj; 795 struct vm_object *vm_obj; 796 797 DRM_LOCK(dev); 798 gem_obj = drm_gem_object_from_offset(dev, *offset); 799 if (gem_obj == NULL) { 800 DRM_UNLOCK(dev); 801 return (ENODEV); 802 } 803 804 drm_gem_object_reference(gem_obj); 805 DRM_UNLOCK(dev); 806 vm_obj = cdev_pager_allocate(gem_obj, OBJT_MGTDEVICE, 807 dev->driver->gem_pager_ops, size, nprot, 808 DRM_GEM_MAPPING_MAPOFF(*offset), curthread->td_ucred); 809 if (vm_obj == NULL) { 810 drm_gem_object_unreference_unlocked(gem_obj); 811 return (EINVAL); 812 } 813 *offset = DRM_GEM_MAPPING_MAPOFF(*offset); 814 *obj_res = vm_obj; 815 return (0); 816 } 817