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#include <linux/types.h> 29#include <linux/slab.h> 30#include <linux/mm.h> 31#include <linux/uaccess.h> 32#include <linux/fs.h> 33#include <linux/file.h> 34#include <linux/module.h> 35#include <linux/mman.h> 36#include <linux/pagemap.h> 37#include <linux/shmem_fs.h> 38#include <linux/dma-buf.h> 39#include <drm/drmP.h> 40#include <drm/drm_vma_manager.h> 41#include <drm/drm_gem.h> 42#include "drm_internal.h" 43 44/** @file drm_gem.c 45 * 46 * This file provides some of the base ioctls and library routines for 47 * the graphics memory manager implemented by each device driver. 48 * 49 * Because various devices have different requirements in terms of 50 * synchronization and migration strategies, implementing that is left up to 51 * the driver, and all that the general API provides should be generic -- 52 * allocating objects, reading/writing data with the cpu, freeing objects. 53 * Even there, platform-dependent optimizations for reading/writing data with 54 * the CPU mean we'll likely hook those out to driver-specific calls. However, 55 * the DRI2 implementation wants to have at least allocate/mmap be generic. 56 * 57 * The goal was to have swap-backed object allocation managed through 58 * struct file. However, file descriptors as handles to a struct file have 59 * two major failings: 60 * - Process limits prevent more than 1024 or so being used at a time by 61 * default. 62 * - Inability to allocate high fds will aggravate the X Server's select() 63 * handling, and likely that of many GL client applications as well. 64 * 65 * This led to a plan of using our own integer IDs (called handles, following 66 * DRM terminology) to mimic fds, and implement the fd syscalls we need as 67 * ioctls. The objects themselves will still include the struct file so 68 * that we can transition to fds if the required kernel infrastructure shows 69 * up at a later date, and as our interface with shmfs for memory allocation. 70 */ 71 72/* 73 * We make up offsets for buffer objects so we can recognize them at 74 * mmap time. 75 */ 76 77/* pgoff in mmap is an unsigned long, so we need to make sure that 78 * the faked up offset will fit 79 */ 80 81#if BITS_PER_LONG == 64 82#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1) 83#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16) 84#else 85#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1) 86#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16) 87#endif 88 89/** 90 * drm_gem_init - Initialize the GEM device fields 91 * @dev: drm_devic structure to initialize 92 */ 93int 94drm_gem_init(struct drm_device *dev) 95{ 96 struct drm_vma_offset_manager *vma_offset_manager; 97 98 mutex_init(&dev->object_name_lock); 99 idr_init(&dev->object_name_idr); 100 101 vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL); 102 if (!vma_offset_manager) { 103 DRM_ERROR("out of memory\n"); 104 return -ENOMEM; 105 } 106 107 dev->vma_offset_manager = vma_offset_manager; 108 drm_vma_offset_manager_init(vma_offset_manager, 109 DRM_FILE_PAGE_OFFSET_START, 110 DRM_FILE_PAGE_OFFSET_SIZE); 111 112 return 0; 113} 114 115void 116drm_gem_destroy(struct drm_device *dev) 117{ 118 119 drm_vma_offset_manager_destroy(dev->vma_offset_manager); 120 kfree(dev->vma_offset_manager); 121 dev->vma_offset_manager = NULL; 122} 123 124/** 125 * drm_gem_object_init - initialize an allocated shmem-backed GEM object 126 * @dev: drm_device the object should be initialized for 127 * @obj: drm_gem_object to initialize 128 * @size: object size 129 * 130 * Initialize an already allocated GEM object of the specified size with 131 * shmfs backing store. 132 */ 133int drm_gem_object_init(struct drm_device *dev, 134 struct drm_gem_object *obj, size_t size) 135{ 136 struct file *filp; 137 138 drm_gem_private_object_init(dev, obj, size); 139 140 filp = shmem_file_setup("drm mm object", size, VM_NORESERVE); 141 if (IS_ERR(filp)) 142 return PTR_ERR(filp); 143 144 obj->filp = filp; 145 146 return 0; 147} 148EXPORT_SYMBOL(drm_gem_object_init); 149 150/** 151 * drm_gem_private_object_init - initialize an allocated private GEM object 152 * @dev: drm_device the object should be initialized for 153 * @obj: drm_gem_object to initialize 154 * @size: object size 155 * 156 * Initialize an already allocated GEM object of the specified size with 157 * no GEM provided backing store. Instead the caller is responsible for 158 * backing the object and handling it. 159 */ 160void drm_gem_private_object_init(struct drm_device *dev, 161 struct drm_gem_object *obj, size_t size) 162{ 163 BUG_ON((size & (PAGE_SIZE - 1)) != 0); 164 165 obj->dev = dev; 166 obj->filp = NULL; 167 168 kref_init(&obj->refcount); 169 obj->handle_count = 0; 170 obj->size = size; 171 drm_vma_node_reset(&obj->vma_node); 172} 173EXPORT_SYMBOL(drm_gem_private_object_init); 174 175static void 176drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp) 177{ 178 /* 179 * Note: obj->dma_buf can't disappear as long as we still hold a 180 * handle reference in obj->handle_count. 181 */ 182 mutex_lock(&filp->prime.lock); 183 if (obj->dma_buf) { 184 drm_prime_remove_buf_handle_locked(&filp->prime, 185 obj->dma_buf); 186 } 187 mutex_unlock(&filp->prime.lock); 188} 189 190/** 191 * drm_gem_object_free - release resources bound to userspace handles 192 * @obj: GEM object to clean up. 193 * 194 * Called after the last handle to the object has been closed 195 * 196 * Removes any name for the object. Note that this must be 197 * called before drm_gem_object_free or we'll be touching 198 * freed memory 199 */ 200static void drm_gem_object_handle_free(struct drm_gem_object *obj) 201{ 202 struct drm_device *dev = obj->dev; 203 204 /* Remove any name for this object */ 205 if (obj->name) { 206 idr_remove(&dev->object_name_idr, obj->name); 207 obj->name = 0; 208 } 209} 210 211static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj) 212{ 213 /* Unbreak the reference cycle if we have an exported dma_buf. */ 214 if (obj->dma_buf) { 215 dma_buf_put(obj->dma_buf); 216 obj->dma_buf = NULL; 217 } 218} 219 220static void 221drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) 222{ 223 if (WARN_ON(obj->handle_count == 0)) 224 return; 225 226 /* 227 * Must bump handle count first as this may be the last 228 * ref, in which case the object would disappear before we 229 * checked for a name 230 */ 231 232 mutex_lock(&obj->dev->object_name_lock); 233 if (--obj->handle_count == 0) { 234 drm_gem_object_handle_free(obj); 235 drm_gem_object_exported_dma_buf_free(obj); 236 } 237 mutex_unlock(&obj->dev->object_name_lock); 238 239 drm_gem_object_unreference_unlocked(obj); 240} 241 242/** 243 * drm_gem_handle_delete - deletes the given file-private handle 244 * @filp: drm file-private structure to use for the handle look up 245 * @handle: userspace handle to delete 246 * 247 * Removes the GEM handle from the @filp lookup table and if this is the last 248 * handle also cleans up linked resources like GEM names. 249 */ 250int 251drm_gem_handle_delete(struct drm_file *filp, u32 handle) 252{ 253 struct drm_device *dev; 254 struct drm_gem_object *obj; 255 256 /* This is gross. The idr system doesn't let us try a delete and 257 * return an error code. It just spews if you fail at deleting. 258 * So, we have to grab a lock around finding the object and then 259 * doing the delete on it and dropping the refcount, or the user 260 * could race us to double-decrement the refcount and cause a 261 * use-after-free later. Given the frequency of our handle lookups, 262 * we may want to use ida for number allocation and a hash table 263 * for the pointers, anyway. 264 */ 265 spin_lock(&filp->table_lock); 266 267 /* Check if we currently have a reference on the object */ 268 obj = idr_find(&filp->object_idr, handle); 269 if (obj == NULL) { 270 spin_unlock(&filp->table_lock); 271 return -EINVAL; 272 } 273 dev = obj->dev; 274 275 /* Release reference and decrement refcount. */ 276 idr_remove(&filp->object_idr, handle); 277 spin_unlock(&filp->table_lock); 278 279 if (drm_core_check_feature(dev, DRIVER_PRIME)) 280 drm_gem_remove_prime_handles(obj, filp); 281 drm_vma_node_revoke(&obj->vma_node, filp->filp); 282 283 if (dev->driver->gem_close_object) 284 dev->driver->gem_close_object(obj, filp); 285 drm_gem_object_handle_unreference_unlocked(obj); 286 287 return 0; 288} 289EXPORT_SYMBOL(drm_gem_handle_delete); 290 291/** 292 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers 293 * @file: drm file-private structure to remove the dumb handle from 294 * @dev: corresponding drm_device 295 * @handle: the dumb handle to remove 296 * 297 * This implements the ->dumb_destroy kms driver callback for drivers which use 298 * gem to manage their backing storage. 299 */ 300int drm_gem_dumb_destroy(struct drm_file *file, 301 struct drm_device *dev, 302 uint32_t handle) 303{ 304 return drm_gem_handle_delete(file, handle); 305} 306EXPORT_SYMBOL(drm_gem_dumb_destroy); 307 308/** 309 * drm_gem_handle_create_tail - internal functions to create a handle 310 * @file_priv: drm file-private structure to register the handle for 311 * @obj: object to register 312 * @handlep: pionter to return the created handle to the caller 313 * 314 * This expects the dev->object_name_lock to be held already and will drop it 315 * before returning. Used to avoid races in establishing new handles when 316 * importing an object from either an flink name or a dma-buf. 317 */ 318int 319drm_gem_handle_create_tail(struct drm_file *file_priv, 320 struct drm_gem_object *obj, 321 u32 *handlep) 322{ 323 struct drm_device *dev = obj->dev; 324 int ret; 325 326 WARN_ON(!mutex_is_locked(&dev->object_name_lock)); 327 328 /* 329 * Get the user-visible handle using idr. Preload and perform 330 * allocation under our spinlock. 331 */ 332 idr_preload(GFP_KERNEL); 333 spin_lock(&file_priv->table_lock); 334 335 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT); 336 drm_gem_object_reference(obj); 337 obj->handle_count++; 338 spin_unlock(&file_priv->table_lock); 339 idr_preload_end(); 340 mutex_unlock(&dev->object_name_lock); 341 if (ret < 0) { 342 drm_gem_object_handle_unreference_unlocked(obj); 343 return ret; 344 } 345 *handlep = ret; 346 347 ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp); 348 if (ret) { 349 drm_gem_handle_delete(file_priv, *handlep); 350 return ret; 351 } 352 353 if (dev->driver->gem_open_object) { 354 ret = dev->driver->gem_open_object(obj, file_priv); 355 if (ret) { 356 drm_gem_handle_delete(file_priv, *handlep); 357 return ret; 358 } 359 } 360 361 return 0; 362} 363 364/** 365 * gem_handle_create - create a gem handle for an object 366 * @file_priv: drm file-private structure to register the handle for 367 * @obj: object to register 368 * @handlep: pionter to return the created handle to the caller 369 * 370 * Create a handle for this object. This adds a handle reference 371 * to the object, which includes a regular reference count. Callers 372 * will likely want to dereference the object afterwards. 373 */ 374int 375drm_gem_handle_create(struct drm_file *file_priv, 376 struct drm_gem_object *obj, 377 u32 *handlep) 378{ 379 mutex_lock(&obj->dev->object_name_lock); 380 381 return drm_gem_handle_create_tail(file_priv, obj, handlep); 382} 383EXPORT_SYMBOL(drm_gem_handle_create); 384 385 386/** 387 * drm_gem_free_mmap_offset - release a fake mmap offset for an object 388 * @obj: obj in question 389 * 390 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset(). 391 */ 392void 393drm_gem_free_mmap_offset(struct drm_gem_object *obj) 394{ 395 struct drm_device *dev = obj->dev; 396 397 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node); 398} 399EXPORT_SYMBOL(drm_gem_free_mmap_offset); 400 401/** 402 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object 403 * @obj: obj in question 404 * @size: the virtual size 405 * 406 * GEM memory mapping works by handing back to userspace a fake mmap offset 407 * it can use in a subsequent mmap(2) call. The DRM core code then looks 408 * up the object based on the offset and sets up the various memory mapping 409 * structures. 410 * 411 * This routine allocates and attaches a fake offset for @obj, in cases where 412 * the virtual size differs from the physical size (ie. obj->size). Otherwise 413 * just use drm_gem_create_mmap_offset(). 414 */ 415int 416drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size) 417{ 418 struct drm_device *dev = obj->dev; 419 420 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node, 421 size / PAGE_SIZE); 422} 423EXPORT_SYMBOL(drm_gem_create_mmap_offset_size); 424 425/** 426 * drm_gem_create_mmap_offset - create a fake mmap offset for an object 427 * @obj: obj in question 428 * 429 * GEM memory mapping works by handing back to userspace a fake mmap offset 430 * it can use in a subsequent mmap(2) call. The DRM core code then looks 431 * up the object based on the offset and sets up the various memory mapping 432 * structures. 433 * 434 * This routine allocates and attaches a fake offset for @obj. 435 */ 436int drm_gem_create_mmap_offset(struct drm_gem_object *obj) 437{ 438 return drm_gem_create_mmap_offset_size(obj, obj->size); 439} 440EXPORT_SYMBOL(drm_gem_create_mmap_offset); 441 442/** 443 * drm_gem_get_pages - helper to allocate backing pages for a GEM object 444 * from shmem 445 * @obj: obj in question 446 * 447 * This reads the page-array of the shmem-backing storage of the given gem 448 * object. An array of pages is returned. If a page is not allocated or 449 * swapped-out, this will allocate/swap-in the required pages. Note that the 450 * whole object is covered by the page-array and pinned in memory. 451 * 452 * Use drm_gem_put_pages() to release the array and unpin all pages. 453 * 454 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()). 455 * If you require other GFP-masks, you have to do those allocations yourself. 456 * 457 * Note that you are not allowed to change gfp-zones during runtime. That is, 458 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as 459 * set during initialization. If you have special zone constraints, set them 460 * after drm_gem_init_object() via mapping_set_gfp_mask(). shmem-core takes care 461 * to keep pages in the required zone during swap-in. 462 */ 463struct page **drm_gem_get_pages(struct drm_gem_object *obj) 464{ 465 struct address_space *mapping; 466 struct page *p, **pages; 467 int i, npages; 468 469 /* This is the shared memory object that backs the GEM resource */ 470 mapping = file_inode(obj->filp)->i_mapping; 471 472 /* We already BUG_ON() for non-page-aligned sizes in 473 * drm_gem_object_init(), so we should never hit this unless 474 * driver author is doing something really wrong: 475 */ 476 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); 477 478 npages = obj->size >> PAGE_SHIFT; 479 480 pages = drm_malloc_ab(npages, sizeof(struct page *)); 481 if (pages == NULL) 482 return ERR_PTR(-ENOMEM); 483 484 for (i = 0; i < npages; i++) { 485 p = shmem_read_mapping_page(mapping, i); 486 if (IS_ERR(p)) 487 goto fail; 488 pages[i] = p; 489 490 /* Make sure shmem keeps __GFP_DMA32 allocated pages in the 491 * correct region during swapin. Note that this requires 492 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping) 493 * so shmem can relocate pages during swapin if required. 494 */ 495 BUG_ON((mapping_gfp_mask(mapping) & __GFP_DMA32) && 496 (page_to_pfn(p) >= 0x00100000UL)); 497 } 498 499 return pages; 500 501fail: 502 while (i--) 503 page_cache_release(pages[i]); 504 505 drm_free_large(pages); 506 return ERR_CAST(p); 507} 508EXPORT_SYMBOL(drm_gem_get_pages); 509 510/** 511 * drm_gem_put_pages - helper to free backing pages for a GEM object 512 * @obj: obj in question 513 * @pages: pages to free 514 * @dirty: if true, pages will be marked as dirty 515 * @accessed: if true, the pages will be marked as accessed 516 */ 517void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages, 518 bool dirty, bool accessed) 519{ 520 int i, npages; 521 522 /* We already BUG_ON() for non-page-aligned sizes in 523 * drm_gem_object_init(), so we should never hit this unless 524 * driver author is doing something really wrong: 525 */ 526 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); 527 528 npages = obj->size >> PAGE_SHIFT; 529 530 for (i = 0; i < npages; i++) { 531 if (dirty) 532 set_page_dirty(pages[i]); 533 534 if (accessed) 535 mark_page_accessed(pages[i]); 536 537 /* Undo the reference we took when populating the table */ 538 page_cache_release(pages[i]); 539 } 540 541 drm_free_large(pages); 542} 543EXPORT_SYMBOL(drm_gem_put_pages); 544 545/** Returns a reference to the object named by the handle. */ 546struct drm_gem_object * 547drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, 548 u32 handle) 549{ 550 struct drm_gem_object *obj; 551 552 spin_lock(&filp->table_lock); 553 554 /* Check if we currently have a reference on the object */ 555 obj = idr_find(&filp->object_idr, handle); 556 if (obj == NULL) { 557 spin_unlock(&filp->table_lock); 558 return NULL; 559 } 560 561 drm_gem_object_reference(obj); 562 563 spin_unlock(&filp->table_lock); 564 565 return obj; 566} 567EXPORT_SYMBOL(drm_gem_object_lookup); 568 569/** 570 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl 571 * @dev: drm_device 572 * @data: ioctl data 573 * @file_priv: drm file-private structure 574 * 575 * Releases the handle to an mm object. 576 */ 577int 578drm_gem_close_ioctl(struct drm_device *dev, void *data, 579 struct drm_file *file_priv) 580{ 581 struct drm_gem_close *args = data; 582 int ret; 583 584 if (!drm_core_check_feature(dev, DRIVER_GEM)) 585 return -ENODEV; 586 587 ret = drm_gem_handle_delete(file_priv, args->handle); 588 589 return ret; 590} 591 592/** 593 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl 594 * @dev: drm_device 595 * @data: ioctl data 596 * @file_priv: drm file-private structure 597 * 598 * Create a global name for an object, returning the name. 599 * 600 * Note that the name does not hold a reference; when the object 601 * is freed, the name goes away. 602 */ 603int 604drm_gem_flink_ioctl(struct drm_device *dev, void *data, 605 struct drm_file *file_priv) 606{ 607 struct drm_gem_flink *args = data; 608 struct drm_gem_object *obj; 609 int ret; 610 611 if (!drm_core_check_feature(dev, DRIVER_GEM)) 612 return -ENODEV; 613 614 obj = drm_gem_object_lookup(dev, file_priv, args->handle); 615 if (obj == NULL) 616 return -ENOENT; 617 618 mutex_lock(&dev->object_name_lock); 619 idr_preload(GFP_KERNEL); 620 /* prevent races with concurrent gem_close. */ 621 if (obj->handle_count == 0) { 622 ret = -ENOENT; 623 goto err; 624 } 625 626 if (!obj->name) { 627 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT); 628 if (ret < 0) 629 goto err; 630 631 obj->name = ret; 632 } 633 634 args->name = (uint64_t) obj->name; 635 ret = 0; 636 637err: 638 idr_preload_end(); 639 mutex_unlock(&dev->object_name_lock); 640 drm_gem_object_unreference_unlocked(obj); 641 return ret; 642} 643 644/** 645 * drm_gem_open - implementation of the GEM_OPEN ioctl 646 * @dev: drm_device 647 * @data: ioctl data 648 * @file_priv: drm file-private structure 649 * 650 * Open an object using the global name, returning a handle and the size. 651 * 652 * This handle (of course) holds a reference to the object, so the object 653 * will not go away until the handle is deleted. 654 */ 655int 656drm_gem_open_ioctl(struct drm_device *dev, void *data, 657 struct drm_file *file_priv) 658{ 659 struct drm_gem_open *args = data; 660 struct drm_gem_object *obj; 661 int ret; 662 u32 handle; 663 664 if (!drm_core_check_feature(dev, DRIVER_GEM)) 665 return -ENODEV; 666 667 mutex_lock(&dev->object_name_lock); 668 obj = idr_find(&dev->object_name_idr, (int) args->name); 669 if (obj) { 670 drm_gem_object_reference(obj); 671 } else { 672 mutex_unlock(&dev->object_name_lock); 673 return -ENOENT; 674 } 675 676 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */ 677 ret = drm_gem_handle_create_tail(file_priv, obj, &handle); 678 drm_gem_object_unreference_unlocked(obj); 679 if (ret) 680 return ret; 681 682 args->handle = handle; 683 args->size = obj->size; 684 685 return 0; 686} 687 688/** 689 * gem_gem_open - initalizes GEM file-private structures at devnode open time 690 * @dev: drm_device which is being opened by userspace 691 * @file_private: drm file-private structure to set up 692 * 693 * Called at device open time, sets up the structure for handling refcounting 694 * of mm objects. 695 */ 696void 697drm_gem_open(struct drm_device *dev, struct drm_file *file_private) 698{ 699 idr_init(&file_private->object_idr); 700 spin_lock_init(&file_private->table_lock); 701} 702 703/* 704 * Called at device close to release the file's 705 * handle references on objects. 706 */ 707static int 708drm_gem_object_release_handle(int id, void *ptr, void *data) 709{ 710 struct drm_file *file_priv = data; 711 struct drm_gem_object *obj = ptr; 712 struct drm_device *dev = obj->dev; 713 714 if (drm_core_check_feature(dev, DRIVER_PRIME)) 715 drm_gem_remove_prime_handles(obj, file_priv); 716 drm_vma_node_revoke(&obj->vma_node, file_priv->filp); 717 718 if (dev->driver->gem_close_object) 719 dev->driver->gem_close_object(obj, file_priv); 720 721 drm_gem_object_handle_unreference_unlocked(obj); 722 723 return 0; 724} 725 726/** 727 * drm_gem_release - release file-private GEM resources 728 * @dev: drm_device which is being closed by userspace 729 * @file_private: drm file-private structure to clean up 730 * 731 * Called at close time when the filp is going away. 732 * 733 * Releases any remaining references on objects by this filp. 734 */ 735void 736drm_gem_release(struct drm_device *dev, struct drm_file *file_private) 737{ 738 idr_for_each(&file_private->object_idr, 739 &drm_gem_object_release_handle, file_private); 740 idr_destroy(&file_private->object_idr); 741} 742 743void 744drm_gem_object_release(struct drm_gem_object *obj) 745{ 746 WARN_ON(obj->dma_buf); 747 748 if (obj->filp) 749 fput(obj->filp); 750 751 drm_gem_free_mmap_offset(obj); 752} 753EXPORT_SYMBOL(drm_gem_object_release); 754 755/** 756 * drm_gem_object_free - free a GEM object 757 * @kref: kref of the object to free 758 * 759 * Called after the last reference to the object has been lost. 760 * Must be called holding struct_ mutex 761 * 762 * Frees the object 763 */ 764void 765drm_gem_object_free(struct kref *kref) 766{ 767 struct drm_gem_object *obj = (struct drm_gem_object *) kref; 768 struct drm_device *dev = obj->dev; 769 770 BUG_ON(!mutex_is_locked(&dev->struct_mutex)); 771 772 if (dev->driver->gem_free_object != NULL) 773 dev->driver->gem_free_object(obj); 774} 775EXPORT_SYMBOL(drm_gem_object_free); 776 777void drm_gem_vm_open(struct vm_area_struct *vma) 778{ 779 struct drm_gem_object *obj = vma->vm_private_data; 780 781 drm_gem_object_reference(obj); 782 783 mutex_lock(&obj->dev->struct_mutex); 784 drm_vm_open_locked(obj->dev, vma); 785 mutex_unlock(&obj->dev->struct_mutex); 786} 787EXPORT_SYMBOL(drm_gem_vm_open); 788 789void drm_gem_vm_close(struct vm_area_struct *vma) 790{ 791 struct drm_gem_object *obj = vma->vm_private_data; 792 struct drm_device *dev = obj->dev; 793 794 mutex_lock(&dev->struct_mutex); 795 drm_vm_close_locked(obj->dev, vma); 796 drm_gem_object_unreference(obj); 797 mutex_unlock(&dev->struct_mutex); 798} 799EXPORT_SYMBOL(drm_gem_vm_close); 800 801/** 802 * drm_gem_mmap_obj - memory map a GEM object 803 * @obj: the GEM object to map 804 * @obj_size: the object size to be mapped, in bytes 805 * @vma: VMA for the area to be mapped 806 * 807 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops 808 * provided by the driver. Depending on their requirements, drivers can either 809 * provide a fault handler in their gem_vm_ops (in which case any accesses to 810 * the object will be trapped, to perform migration, GTT binding, surface 811 * register allocation, or performance monitoring), or mmap the buffer memory 812 * synchronously after calling drm_gem_mmap_obj. 813 * 814 * This function is mainly intended to implement the DMABUF mmap operation, when 815 * the GEM object is not looked up based on its fake offset. To implement the 816 * DRM mmap operation, drivers should use the drm_gem_mmap() function. 817 * 818 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while 819 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So 820 * callers must verify access restrictions before calling this helper. 821 * 822 * NOTE: This function has to be protected with dev->struct_mutex 823 * 824 * Return 0 or success or -EINVAL if the object size is smaller than the VMA 825 * size, or if no gem_vm_ops are provided. 826 */ 827int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, 828 struct vm_area_struct *vma) 829{ 830 struct drm_device *dev = obj->dev; 831 832 lockdep_assert_held(&dev->struct_mutex); 833 834 /* Check for valid size. */ 835 if (obj_size < vma->vm_end - vma->vm_start) 836 return -EINVAL; 837 838 if (!dev->driver->gem_vm_ops) 839 return -EINVAL; 840 841 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; 842 vma->vm_ops = dev->driver->gem_vm_ops; 843 vma->vm_private_data = obj; 844 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); 845 846 /* Take a ref for this mapping of the object, so that the fault 847 * handler can dereference the mmap offset's pointer to the object. 848 * This reference is cleaned up by the corresponding vm_close 849 * (which should happen whether the vma was created by this call, or 850 * by a vm_open due to mremap or partial unmap or whatever). 851 */ 852 drm_gem_object_reference(obj); 853 854 drm_vm_open_locked(dev, vma); 855 return 0; 856} 857EXPORT_SYMBOL(drm_gem_mmap_obj); 858 859/** 860 * drm_gem_mmap - memory map routine for GEM objects 861 * @filp: DRM file pointer 862 * @vma: VMA for the area to be mapped 863 * 864 * If a driver supports GEM object mapping, mmap calls on the DRM file 865 * descriptor will end up here. 866 * 867 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will 868 * contain the fake offset we created when the GTT map ioctl was called on 869 * the object) and map it with a call to drm_gem_mmap_obj(). 870 * 871 * If the caller is not granted access to the buffer object, the mmap will fail 872 * with EACCES. Please see the vma manager for more information. 873 */ 874int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) 875{ 876 struct drm_file *priv = filp->private_data; 877 struct drm_device *dev = priv->minor->dev; 878 struct drm_gem_object *obj; 879 struct drm_vma_offset_node *node; 880 int ret; 881 882 if (drm_device_is_unplugged(dev)) 883 return -ENODEV; 884 885 mutex_lock(&dev->struct_mutex); 886 887 node = drm_vma_offset_exact_lookup(dev->vma_offset_manager, 888 vma->vm_pgoff, 889 vma_pages(vma)); 890 if (!node) { 891 mutex_unlock(&dev->struct_mutex); 892 return -EINVAL; 893 } else if (!drm_vma_node_is_allowed(node, filp)) { 894 mutex_unlock(&dev->struct_mutex); 895 return -EACCES; 896 } 897 898 obj = container_of(node, struct drm_gem_object, vma_node); 899 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, vma); 900 901 mutex_unlock(&dev->struct_mutex); 902 903 return ret; 904} 905EXPORT_SYMBOL(drm_gem_mmap); 906