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 <linux/mem_encrypt.h> 40#include <linux/pagevec.h> 41 42#include <drm/drm.h> 43#include <drm/drm_device.h> 44#include <drm/drm_drv.h> 45#include <drm/drm_file.h> 46#include <drm/drm_gem.h> 47#include <drm/drm_managed.h> 48#include <drm/drm_print.h> 49#include <drm/drm_vma_manager.h> 50 51#include "drm_internal.h" 52 53/** @file drm_gem.c 54 * 55 * This file provides some of the base ioctls and library routines for 56 * the graphics memory manager implemented by each device driver. 57 * 58 * Because various devices have different requirements in terms of 59 * synchronization and migration strategies, implementing that is left up to 60 * the driver, and all that the general API provides should be generic -- 61 * allocating objects, reading/writing data with the cpu, freeing objects. 62 * Even there, platform-dependent optimizations for reading/writing data with 63 * the CPU mean we'll likely hook those out to driver-specific calls. However, 64 * the DRI2 implementation wants to have at least allocate/mmap be generic. 65 * 66 * The goal was to have swap-backed object allocation managed through 67 * struct file. However, file descriptors as handles to a struct file have 68 * two major failings: 69 * - Process limits prevent more than 1024 or so being used at a time by 70 * default. 71 * - Inability to allocate high fds will aggravate the X Server's select() 72 * handling, and likely that of many GL client applications as well. 73 * 74 * This led to a plan of using our own integer IDs (called handles, following 75 * DRM terminology) to mimic fds, and implement the fd syscalls we need as 76 * ioctls. The objects themselves will still include the struct file so 77 * that we can transition to fds if the required kernel infrastructure shows 78 * up at a later date, and as our interface with shmfs for memory allocation. 79 */ 80 81static void 82drm_gem_init_release(struct drm_device *dev, void *ptr) 83{ 84 drm_vma_offset_manager_destroy(dev->vma_offset_manager); 85} 86 87/** 88 * drm_gem_init - Initialize the GEM device fields 89 * @dev: drm_devic structure to initialize 90 */ 91int 92drm_gem_init(struct drm_device *dev) 93{ 94 struct drm_vma_offset_manager *vma_offset_manager; 95 96 mutex_init(&dev->object_name_lock); 97 idr_init_base(&dev->object_name_idr, 1); 98 99 vma_offset_manager = drmm_kzalloc(dev, sizeof(*vma_offset_manager), 100 GFP_KERNEL); 101 if (!vma_offset_manager) { 102 DRM_ERROR("out of memory\n"); 103 return -ENOMEM; 104 } 105 106 dev->vma_offset_manager = vma_offset_manager; 107 drm_vma_offset_manager_init(vma_offset_manager, 108 DRM_FILE_PAGE_OFFSET_START, 109 DRM_FILE_PAGE_OFFSET_SIZE); 110 111 return drmm_add_action(dev, drm_gem_init_release, NULL); 112} 113 114/** 115 * drm_gem_object_init - initialize an allocated shmem-backed GEM object 116 * @dev: drm_device the object should be initialized for 117 * @obj: drm_gem_object to initialize 118 * @size: object size 119 * 120 * Initialize an already allocated GEM object of the specified size with 121 * shmfs backing store. 122 */ 123int drm_gem_object_init(struct drm_device *dev, 124 struct drm_gem_object *obj, size_t size) 125{ 126 struct file *filp; 127 128 drm_gem_private_object_init(dev, obj, size); 129 130 filp = shmem_file_setup("drm mm object", size, VM_NORESERVE); 131 if (IS_ERR(filp)) 132 return PTR_ERR(filp); 133 134 obj->filp = filp; 135 136 return 0; 137} 138EXPORT_SYMBOL(drm_gem_object_init); 139 140/** 141 * drm_gem_private_object_init - initialize an allocated private GEM object 142 * @dev: drm_device the object should be initialized for 143 * @obj: drm_gem_object to initialize 144 * @size: object size 145 * 146 * Initialize an already allocated GEM object of the specified size with 147 * no GEM provided backing store. Instead the caller is responsible for 148 * backing the object and handling it. 149 */ 150void drm_gem_private_object_init(struct drm_device *dev, 151 struct drm_gem_object *obj, size_t size) 152{ 153 BUG_ON((size & (PAGE_SIZE - 1)) != 0); 154 155 obj->dev = dev; 156 obj->filp = NULL; 157 158 kref_init(&obj->refcount); 159 obj->handle_count = 0; 160 obj->size = size; 161 dma_resv_init(&obj->_resv); 162 if (!obj->resv) 163 obj->resv = &obj->_resv; 164 165 drm_vma_node_reset(&obj->vma_node); 166} 167EXPORT_SYMBOL(drm_gem_private_object_init); 168 169/** 170 * drm_gem_object_handle_free - release resources bound to userspace handles 171 * @obj: GEM object to clean up. 172 * 173 * Called after the last handle to the object has been closed 174 * 175 * Removes any name for the object. Note that this must be 176 * called before drm_gem_object_free or we'll be touching 177 * freed memory 178 */ 179static void drm_gem_object_handle_free(struct drm_gem_object *obj) 180{ 181 struct drm_device *dev = obj->dev; 182 183 /* Remove any name for this object */ 184 if (obj->name) { 185 idr_remove(&dev->object_name_idr, obj->name); 186 obj->name = 0; 187 } 188} 189 190static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj) 191{ 192 /* Unbreak the reference cycle if we have an exported dma_buf. */ 193 if (obj->dma_buf) { 194 dma_buf_put(obj->dma_buf); 195 obj->dma_buf = NULL; 196 } 197} 198 199static void 200drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj) 201{ 202 struct drm_device *dev = obj->dev; 203 bool final = false; 204 205 if (WARN_ON(READ_ONCE(obj->handle_count) == 0)) 206 return; 207 208 /* 209 * Must bump handle count first as this may be the last 210 * ref, in which case the object would disappear before we 211 * checked for a name 212 */ 213 214 mutex_lock(&dev->object_name_lock); 215 if (--obj->handle_count == 0) { 216 drm_gem_object_handle_free(obj); 217 drm_gem_object_exported_dma_buf_free(obj); 218 final = true; 219 } 220 mutex_unlock(&dev->object_name_lock); 221 222 if (final) 223 drm_gem_object_put(obj); 224} 225 226/* 227 * Called at device or object close to release the file's 228 * handle references on objects. 229 */ 230static int 231drm_gem_object_release_handle(int id, void *ptr, void *data) 232{ 233 struct drm_file *file_priv = data; 234 struct drm_gem_object *obj = ptr; 235 struct drm_device *dev = obj->dev; 236 237 if (obj->funcs && obj->funcs->close) 238 obj->funcs->close(obj, file_priv); 239 else if (dev->driver->gem_close_object) 240 dev->driver->gem_close_object(obj, file_priv); 241 242 drm_prime_remove_buf_handle(&file_priv->prime, id); 243 drm_vma_node_revoke(&obj->vma_node, file_priv); 244 245 drm_gem_object_handle_put_unlocked(obj); 246 247 return 0; 248} 249 250/** 251 * drm_gem_handle_delete - deletes the given file-private handle 252 * @filp: drm file-private structure to use for the handle look up 253 * @handle: userspace handle to delete 254 * 255 * Removes the GEM handle from the @filp lookup table which has been added with 256 * drm_gem_handle_create(). If this is the last handle also cleans up linked 257 * resources like GEM names. 258 */ 259int 260drm_gem_handle_delete(struct drm_file *filp, u32 handle) 261{ 262 struct drm_gem_object *obj; 263 264 spin_lock(&filp->table_lock); 265 266 /* Check if we currently have a reference on the object */ 267 obj = idr_replace(&filp->object_idr, NULL, handle); 268 spin_unlock(&filp->table_lock); 269 if (IS_ERR_OR_NULL(obj)) 270 return -EINVAL; 271 272 /* Release driver's reference and decrement refcount. */ 273 drm_gem_object_release_handle(handle, obj, filp); 274 275 /* And finally make the handle available for future allocations. */ 276 spin_lock(&filp->table_lock); 277 idr_remove(&filp->object_idr, handle); 278 spin_unlock(&filp->table_lock); 279 280 return 0; 281} 282EXPORT_SYMBOL(drm_gem_handle_delete); 283 284/** 285 * drm_gem_dumb_map_offset - return the fake mmap offset for a gem object 286 * @file: drm file-private structure containing the gem object 287 * @dev: corresponding drm_device 288 * @handle: gem object handle 289 * @offset: return location for the fake mmap offset 290 * 291 * This implements the &drm_driver.dumb_map_offset kms driver callback for 292 * drivers which use gem to manage their backing storage. 293 * 294 * Returns: 295 * 0 on success or a negative error code on failure. 296 */ 297int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, 298 u32 handle, u64 *offset) 299{ 300 struct drm_gem_object *obj; 301 int ret; 302 303 obj = drm_gem_object_lookup(file, handle); 304 if (!obj) 305 return -ENOENT; 306 307 /* Don't allow imported objects to be mapped */ 308 if (obj->import_attach) { 309 ret = -EINVAL; 310 goto out; 311 } 312 313 ret = drm_gem_create_mmap_offset(obj); 314 if (ret) 315 goto out; 316 317 *offset = drm_vma_node_offset_addr(&obj->vma_node); 318out: 319 drm_gem_object_put(obj); 320 321 return ret; 322} 323EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset); 324 325/** 326 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers 327 * @file: drm file-private structure to remove the dumb handle from 328 * @dev: corresponding drm_device 329 * @handle: the dumb handle to remove 330 * 331 * This implements the &drm_driver.dumb_destroy kms driver callback for drivers 332 * which use gem to manage their backing storage. 333 */ 334int drm_gem_dumb_destroy(struct drm_file *file, 335 struct drm_device *dev, 336 uint32_t handle) 337{ 338 return drm_gem_handle_delete(file, handle); 339} 340EXPORT_SYMBOL(drm_gem_dumb_destroy); 341 342/** 343 * drm_gem_handle_create_tail - internal functions to create a handle 344 * @file_priv: drm file-private structure to register the handle for 345 * @obj: object to register 346 * @handlep: pointer to return the created handle to the caller 347 * 348 * This expects the &drm_device.object_name_lock to be held already and will 349 * drop it before returning. Used to avoid races in establishing new handles 350 * when importing an object from either an flink name or a dma-buf. 351 * 352 * Handles must be release again through drm_gem_handle_delete(). This is done 353 * when userspace closes @file_priv for all attached handles, or through the 354 * GEM_CLOSE ioctl for individual handles. 355 */ 356int 357drm_gem_handle_create_tail(struct drm_file *file_priv, 358 struct drm_gem_object *obj, 359 u32 *handlep) 360{ 361 struct drm_device *dev = obj->dev; 362 u32 handle; 363 int ret; 364 365 WARN_ON(!mutex_is_locked(&dev->object_name_lock)); 366 if (obj->handle_count++ == 0) 367 drm_gem_object_get(obj); 368 369 /* 370 * Get the user-visible handle using idr. Preload and perform 371 * allocation under our spinlock. 372 */ 373 idr_preload(GFP_KERNEL); 374 spin_lock(&file_priv->table_lock); 375 376 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT); 377 378 spin_unlock(&file_priv->table_lock); 379 idr_preload_end(); 380 381 mutex_unlock(&dev->object_name_lock); 382 if (ret < 0) 383 goto err_unref; 384 385 handle = ret; 386 387 ret = drm_vma_node_allow(&obj->vma_node, file_priv); 388 if (ret) 389 goto err_remove; 390 391 if (obj->funcs && obj->funcs->open) { 392 ret = obj->funcs->open(obj, file_priv); 393 if (ret) 394 goto err_revoke; 395 } else if (dev->driver->gem_open_object) { 396 ret = dev->driver->gem_open_object(obj, file_priv); 397 if (ret) 398 goto err_revoke; 399 } 400 401 *handlep = handle; 402 return 0; 403 404err_revoke: 405 drm_vma_node_revoke(&obj->vma_node, file_priv); 406err_remove: 407 spin_lock(&file_priv->table_lock); 408 idr_remove(&file_priv->object_idr, handle); 409 spin_unlock(&file_priv->table_lock); 410err_unref: 411 drm_gem_object_handle_put_unlocked(obj); 412 return ret; 413} 414 415/** 416 * drm_gem_handle_create - create a gem handle for an object 417 * @file_priv: drm file-private structure to register the handle for 418 * @obj: object to register 419 * @handlep: pointer to return the created handle to the caller 420 * 421 * Create a handle for this object. This adds a handle reference to the object, 422 * which includes a regular reference count. Callers will likely want to 423 * dereference the object afterwards. 424 * 425 * Since this publishes @obj to userspace it must be fully set up by this point, 426 * drivers must call this last in their buffer object creation callbacks. 427 */ 428int drm_gem_handle_create(struct drm_file *file_priv, 429 struct drm_gem_object *obj, 430 u32 *handlep) 431{ 432 mutex_lock(&obj->dev->object_name_lock); 433 434 return drm_gem_handle_create_tail(file_priv, obj, handlep); 435} 436EXPORT_SYMBOL(drm_gem_handle_create); 437 438 439/** 440 * drm_gem_free_mmap_offset - release a fake mmap offset for an object 441 * @obj: obj in question 442 * 443 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset(). 444 * 445 * Note that drm_gem_object_release() already calls this function, so drivers 446 * don't have to take care of releasing the mmap offset themselves when freeing 447 * the GEM object. 448 */ 449void 450drm_gem_free_mmap_offset(struct drm_gem_object *obj) 451{ 452 struct drm_device *dev = obj->dev; 453 454 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node); 455} 456EXPORT_SYMBOL(drm_gem_free_mmap_offset); 457 458/** 459 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object 460 * @obj: obj in question 461 * @size: the virtual size 462 * 463 * GEM memory mapping works by handing back to userspace a fake mmap offset 464 * it can use in a subsequent mmap(2) call. The DRM core code then looks 465 * up the object based on the offset and sets up the various memory mapping 466 * structures. 467 * 468 * This routine allocates and attaches a fake offset for @obj, in cases where 469 * the virtual size differs from the physical size (ie. &drm_gem_object.size). 470 * Otherwise just use drm_gem_create_mmap_offset(). 471 * 472 * This function is idempotent and handles an already allocated mmap offset 473 * transparently. Drivers do not need to check for this case. 474 */ 475int 476drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size) 477{ 478 struct drm_device *dev = obj->dev; 479 480 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node, 481 size / PAGE_SIZE); 482} 483EXPORT_SYMBOL(drm_gem_create_mmap_offset_size); 484 485/** 486 * drm_gem_create_mmap_offset - create a fake mmap offset for an object 487 * @obj: obj in question 488 * 489 * GEM memory mapping works by handing back to userspace a fake mmap offset 490 * it can use in a subsequent mmap(2) call. The DRM core code then looks 491 * up the object based on the offset and sets up the various memory mapping 492 * structures. 493 * 494 * This routine allocates and attaches a fake offset for @obj. 495 * 496 * Drivers can call drm_gem_free_mmap_offset() before freeing @obj to release 497 * the fake offset again. 498 */ 499int drm_gem_create_mmap_offset(struct drm_gem_object *obj) 500{ 501 return drm_gem_create_mmap_offset_size(obj, obj->size); 502} 503EXPORT_SYMBOL(drm_gem_create_mmap_offset); 504 505/* 506 * Move pages to appropriate lru and release the pagevec, decrementing the 507 * ref count of those pages. 508 */ 509static void drm_gem_check_release_pagevec(struct pagevec *pvec) 510{ 511 check_move_unevictable_pages(pvec); 512 __pagevec_release(pvec); 513 cond_resched(); 514} 515 516/** 517 * drm_gem_get_pages - helper to allocate backing pages for a GEM object 518 * from shmem 519 * @obj: obj in question 520 * 521 * This reads the page-array of the shmem-backing storage of the given gem 522 * object. An array of pages is returned. If a page is not allocated or 523 * swapped-out, this will allocate/swap-in the required pages. Note that the 524 * whole object is covered by the page-array and pinned in memory. 525 * 526 * Use drm_gem_put_pages() to release the array and unpin all pages. 527 * 528 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()). 529 * If you require other GFP-masks, you have to do those allocations yourself. 530 * 531 * Note that you are not allowed to change gfp-zones during runtime. That is, 532 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as 533 * set during initialization. If you have special zone constraints, set them 534 * after drm_gem_object_init() via mapping_set_gfp_mask(). shmem-core takes care 535 * to keep pages in the required zone during swap-in. 536 * 537 * This function is only valid on objects initialized with 538 * drm_gem_object_init(), but not for those initialized with 539 * drm_gem_private_object_init() only. 540 */ 541struct page **drm_gem_get_pages(struct drm_gem_object *obj) 542{ 543 struct address_space *mapping; 544 struct page *p, **pages; 545 struct pagevec pvec; 546 int i, npages; 547 548 549 if (WARN_ON(!obj->filp)) 550 return ERR_PTR(-EINVAL); 551 552 /* This is the shared memory object that backs the GEM resource */ 553 mapping = obj->filp->f_mapping; 554 555 /* We already BUG_ON() for non-page-aligned sizes in 556 * drm_gem_object_init(), so we should never hit this unless 557 * driver author is doing something really wrong: 558 */ 559 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); 560 561 npages = obj->size >> PAGE_SHIFT; 562 563 pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); 564 if (pages == NULL) 565 return ERR_PTR(-ENOMEM); 566 567 mapping_set_unevictable(mapping); 568 569 for (i = 0; i < npages; i++) { 570 p = shmem_read_mapping_page(mapping, i); 571 if (IS_ERR(p)) 572 goto fail; 573 pages[i] = p; 574 575 /* Make sure shmem keeps __GFP_DMA32 allocated pages in the 576 * correct region during swapin. Note that this requires 577 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping) 578 * so shmem can relocate pages during swapin if required. 579 */ 580 BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) && 581 (page_to_pfn(p) >= 0x00100000UL)); 582 } 583 584 return pages; 585 586fail: 587 mapping_clear_unevictable(mapping); 588 pagevec_init(&pvec); 589 while (i--) { 590 if (!pagevec_add(&pvec, pages[i])) 591 drm_gem_check_release_pagevec(&pvec); 592 } 593 if (pagevec_count(&pvec)) 594 drm_gem_check_release_pagevec(&pvec); 595 596 kvfree(pages); 597 return ERR_CAST(p); 598} 599EXPORT_SYMBOL(drm_gem_get_pages); 600 601/** 602 * drm_gem_put_pages - helper to free backing pages for a GEM object 603 * @obj: obj in question 604 * @pages: pages to free 605 * @dirty: if true, pages will be marked as dirty 606 * @accessed: if true, the pages will be marked as accessed 607 */ 608void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages, 609 bool dirty, bool accessed) 610{ 611 int i, npages; 612 struct address_space *mapping; 613 struct pagevec pvec; 614 615 mapping = file_inode(obj->filp)->i_mapping; 616 mapping_clear_unevictable(mapping); 617 618 /* We already BUG_ON() for non-page-aligned sizes in 619 * drm_gem_object_init(), so we should never hit this unless 620 * driver author is doing something really wrong: 621 */ 622 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); 623 624 npages = obj->size >> PAGE_SHIFT; 625 626 pagevec_init(&pvec); 627 for (i = 0; i < npages; i++) { 628 if (!pages[i]) 629 continue; 630 631 if (dirty) 632 set_page_dirty(pages[i]); 633 634 if (accessed) 635 mark_page_accessed(pages[i]); 636 637 /* Undo the reference we took when populating the table */ 638 if (!pagevec_add(&pvec, pages[i])) 639 drm_gem_check_release_pagevec(&pvec); 640 } 641 if (pagevec_count(&pvec)) 642 drm_gem_check_release_pagevec(&pvec); 643 644 kvfree(pages); 645} 646EXPORT_SYMBOL(drm_gem_put_pages); 647 648static int objects_lookup(struct drm_file *filp, u32 *handle, int count, 649 struct drm_gem_object **objs) 650{ 651 int i, ret = 0; 652 struct drm_gem_object *obj; 653 654 spin_lock(&filp->table_lock); 655 656 for (i = 0; i < count; i++) { 657 /* Check if we currently have a reference on the object */ 658 obj = idr_find(&filp->object_idr, handle[i]); 659 if (!obj) { 660 ret = -ENOENT; 661 break; 662 } 663 drm_gem_object_get(obj); 664 objs[i] = obj; 665 } 666 spin_unlock(&filp->table_lock); 667 668 return ret; 669} 670 671/** 672 * drm_gem_objects_lookup - look up GEM objects from an array of handles 673 * @filp: DRM file private date 674 * @bo_handles: user pointer to array of userspace handle 675 * @count: size of handle array 676 * @objs_out: returned pointer to array of drm_gem_object pointers 677 * 678 * Takes an array of userspace handles and returns a newly allocated array of 679 * GEM objects. 680 * 681 * For a single handle lookup, use drm_gem_object_lookup(). 682 * 683 * Returns: 684 * 685 * @objs filled in with GEM object pointers. Returned GEM objects need to be 686 * released with drm_gem_object_put(). -ENOENT is returned on a lookup 687 * failure. 0 is returned on success. 688 * 689 */ 690int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles, 691 int count, struct drm_gem_object ***objs_out) 692{ 693 int ret; 694 u32 *handles; 695 struct drm_gem_object **objs; 696 697 if (!count) 698 return 0; 699 700 objs = kvmalloc_array(count, sizeof(struct drm_gem_object *), 701 GFP_KERNEL | __GFP_ZERO); 702 if (!objs) 703 return -ENOMEM; 704 705 *objs_out = objs; 706 707 handles = kvmalloc_array(count, sizeof(u32), GFP_KERNEL); 708 if (!handles) { 709 ret = -ENOMEM; 710 goto out; 711 } 712 713 if (copy_from_user(handles, bo_handles, count * sizeof(u32))) { 714 ret = -EFAULT; 715 DRM_DEBUG("Failed to copy in GEM handles\n"); 716 goto out; 717 } 718 719 ret = objects_lookup(filp, handles, count, objs); 720out: 721 kvfree(handles); 722 return ret; 723 724} 725EXPORT_SYMBOL(drm_gem_objects_lookup); 726 727/** 728 * drm_gem_object_lookup - look up a GEM object from its handle 729 * @filp: DRM file private date 730 * @handle: userspace handle 731 * 732 * Returns: 733 * 734 * A reference to the object named by the handle if such exists on @filp, NULL 735 * otherwise. 736 * 737 * If looking up an array of handles, use drm_gem_objects_lookup(). 738 */ 739struct drm_gem_object * 740drm_gem_object_lookup(struct drm_file *filp, u32 handle) 741{ 742 struct drm_gem_object *obj = NULL; 743 744 objects_lookup(filp, &handle, 1, &obj); 745 return obj; 746} 747EXPORT_SYMBOL(drm_gem_object_lookup); 748 749/** 750 * drm_gem_dma_resv_wait - Wait on GEM object's reservation's objects 751 * shared and/or exclusive fences. 752 * @filep: DRM file private date 753 * @handle: userspace handle 754 * @wait_all: if true, wait on all fences, else wait on just exclusive fence 755 * @timeout: timeout value in jiffies or zero to return immediately 756 * 757 * Returns: 758 * 759 * Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or 760 * greater than 0 on success. 761 */ 762long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle, 763 bool wait_all, unsigned long timeout) 764{ 765 long ret; 766 struct drm_gem_object *obj; 767 768 obj = drm_gem_object_lookup(filep, handle); 769 if (!obj) { 770 DRM_DEBUG("Failed to look up GEM BO %d\n", handle); 771 return -EINVAL; 772 } 773 774 ret = dma_resv_wait_timeout_rcu(obj->resv, wait_all, 775 true, timeout); 776 if (ret == 0) 777 ret = -ETIME; 778 else if (ret > 0) 779 ret = 0; 780 781 drm_gem_object_put(obj); 782 783 return ret; 784} 785EXPORT_SYMBOL(drm_gem_dma_resv_wait); 786 787/** 788 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl 789 * @dev: drm_device 790 * @data: ioctl data 791 * @file_priv: drm file-private structure 792 * 793 * Releases the handle to an mm object. 794 */ 795int 796drm_gem_close_ioctl(struct drm_device *dev, void *data, 797 struct drm_file *file_priv) 798{ 799 struct drm_gem_close *args = data; 800 int ret; 801 802 if (!drm_core_check_feature(dev, DRIVER_GEM)) 803 return -EOPNOTSUPP; 804 805 ret = drm_gem_handle_delete(file_priv, args->handle); 806 807 return ret; 808} 809 810/** 811 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl 812 * @dev: drm_device 813 * @data: ioctl data 814 * @file_priv: drm file-private structure 815 * 816 * Create a global name for an object, returning the name. 817 * 818 * Note that the name does not hold a reference; when the object 819 * is freed, the name goes away. 820 */ 821int 822drm_gem_flink_ioctl(struct drm_device *dev, void *data, 823 struct drm_file *file_priv) 824{ 825 struct drm_gem_flink *args = data; 826 struct drm_gem_object *obj; 827 int ret; 828 829 if (!drm_core_check_feature(dev, DRIVER_GEM)) 830 return -EOPNOTSUPP; 831 832 obj = drm_gem_object_lookup(file_priv, args->handle); 833 if (obj == NULL) 834 return -ENOENT; 835 836 mutex_lock(&dev->object_name_lock); 837 /* prevent races with concurrent gem_close. */ 838 if (obj->handle_count == 0) { 839 ret = -ENOENT; 840 goto err; 841 } 842 843 if (!obj->name) { 844 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_KERNEL); 845 if (ret < 0) 846 goto err; 847 848 obj->name = ret; 849 } 850 851 args->name = (uint64_t) obj->name; 852 ret = 0; 853 854err: 855 mutex_unlock(&dev->object_name_lock); 856 drm_gem_object_put(obj); 857 return ret; 858} 859 860/** 861 * drm_gem_open - implementation of the GEM_OPEN ioctl 862 * @dev: drm_device 863 * @data: ioctl data 864 * @file_priv: drm file-private structure 865 * 866 * Open an object using the global name, returning a handle and the size. 867 * 868 * This handle (of course) holds a reference to the object, so the object 869 * will not go away until the handle is deleted. 870 */ 871int 872drm_gem_open_ioctl(struct drm_device *dev, void *data, 873 struct drm_file *file_priv) 874{ 875 struct drm_gem_open *args = data; 876 struct drm_gem_object *obj; 877 int ret; 878 u32 handle; 879 880 if (!drm_core_check_feature(dev, DRIVER_GEM)) 881 return -EOPNOTSUPP; 882 883 mutex_lock(&dev->object_name_lock); 884 obj = idr_find(&dev->object_name_idr, (int) args->name); 885 if (obj) { 886 drm_gem_object_get(obj); 887 } else { 888 mutex_unlock(&dev->object_name_lock); 889 return -ENOENT; 890 } 891 892 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */ 893 ret = drm_gem_handle_create_tail(file_priv, obj, &handle); 894 if (ret) 895 goto err; 896 897 args->handle = handle; 898 args->size = obj->size; 899 900err: 901 drm_gem_object_put(obj); 902 return ret; 903} 904 905/** 906 * gem_gem_open - initalizes GEM file-private structures at devnode open time 907 * @dev: drm_device which is being opened by userspace 908 * @file_private: drm file-private structure to set up 909 * 910 * Called at device open time, sets up the structure for handling refcounting 911 * of mm objects. 912 */ 913void 914drm_gem_open(struct drm_device *dev, struct drm_file *file_private) 915{ 916 idr_init_base(&file_private->object_idr, 1); 917 spin_lock_init(&file_private->table_lock); 918} 919 920/** 921 * drm_gem_release - release file-private GEM resources 922 * @dev: drm_device which is being closed by userspace 923 * @file_private: drm file-private structure to clean up 924 * 925 * Called at close time when the filp is going away. 926 * 927 * Releases any remaining references on objects by this filp. 928 */ 929void 930drm_gem_release(struct drm_device *dev, struct drm_file *file_private) 931{ 932 idr_for_each(&file_private->object_idr, 933 &drm_gem_object_release_handle, file_private); 934 idr_destroy(&file_private->object_idr); 935} 936 937/** 938 * drm_gem_object_release - release GEM buffer object resources 939 * @obj: GEM buffer object 940 * 941 * This releases any structures and resources used by @obj and is the invers of 942 * drm_gem_object_init(). 943 */ 944void 945drm_gem_object_release(struct drm_gem_object *obj) 946{ 947 WARN_ON(obj->dma_buf); 948 949 if (obj->filp) 950 fput(obj->filp); 951 952 dma_resv_fini(&obj->_resv); 953 drm_gem_free_mmap_offset(obj); 954} 955EXPORT_SYMBOL(drm_gem_object_release); 956 957/** 958 * drm_gem_object_free - free a GEM object 959 * @kref: kref of the object to free 960 * 961 * Called after the last reference to the object has been lost. 962 * 963 * Frees the object 964 */ 965void 966drm_gem_object_free(struct kref *kref) 967{ 968 struct drm_gem_object *obj = 969 container_of(kref, struct drm_gem_object, refcount); 970 struct drm_device *dev = obj->dev; 971 972 if (obj->funcs) 973 obj->funcs->free(obj); 974 else if (dev->driver->gem_free_object_unlocked) 975 dev->driver->gem_free_object_unlocked(obj); 976} 977EXPORT_SYMBOL(drm_gem_object_free); 978 979/** 980 * drm_gem_object_put_locked - release a GEM buffer object reference 981 * @obj: GEM buffer object 982 * 983 * This releases a reference to @obj. Callers must hold the 984 * &drm_device.struct_mutex lock when calling this function, even when the 985 * driver doesn't use &drm_device.struct_mutex for anything. 986 * 987 * For drivers not encumbered with legacy locking use 988 * drm_gem_object_put() instead. 989 */ 990void 991drm_gem_object_put_locked(struct drm_gem_object *obj) 992{ 993 if (obj) { 994 WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex)); 995 996 kref_put(&obj->refcount, drm_gem_object_free); 997 } 998} 999EXPORT_SYMBOL(drm_gem_object_put_locked); 1000 1001/** 1002 * drm_gem_vm_open - vma->ops->open implementation for GEM 1003 * @vma: VM area structure 1004 * 1005 * This function implements the #vm_operations_struct open() callback for GEM 1006 * drivers. This must be used together with drm_gem_vm_close(). 1007 */ 1008void drm_gem_vm_open(struct vm_area_struct *vma) 1009{ 1010 struct drm_gem_object *obj = vma->vm_private_data; 1011 1012 drm_gem_object_get(obj); 1013} 1014EXPORT_SYMBOL(drm_gem_vm_open); 1015 1016/** 1017 * drm_gem_vm_close - vma->ops->close implementation for GEM 1018 * @vma: VM area structure 1019 * 1020 * This function implements the #vm_operations_struct close() callback for GEM 1021 * drivers. This must be used together with drm_gem_vm_open(). 1022 */ 1023void drm_gem_vm_close(struct vm_area_struct *vma) 1024{ 1025 struct drm_gem_object *obj = vma->vm_private_data; 1026 1027 drm_gem_object_put(obj); 1028} 1029EXPORT_SYMBOL(drm_gem_vm_close); 1030 1031/** 1032 * drm_gem_mmap_obj - memory map a GEM object 1033 * @obj: the GEM object to map 1034 * @obj_size: the object size to be mapped, in bytes 1035 * @vma: VMA for the area to be mapped 1036 * 1037 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops 1038 * provided by the driver. Depending on their requirements, drivers can either 1039 * provide a fault handler in their gem_vm_ops (in which case any accesses to 1040 * the object will be trapped, to perform migration, GTT binding, surface 1041 * register allocation, or performance monitoring), or mmap the buffer memory 1042 * synchronously after calling drm_gem_mmap_obj. 1043 * 1044 * This function is mainly intended to implement the DMABUF mmap operation, when 1045 * the GEM object is not looked up based on its fake offset. To implement the 1046 * DRM mmap operation, drivers should use the drm_gem_mmap() function. 1047 * 1048 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while 1049 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So 1050 * callers must verify access restrictions before calling this helper. 1051 * 1052 * Return 0 or success or -EINVAL if the object size is smaller than the VMA 1053 * size, or if no gem_vm_ops are provided. 1054 */ 1055int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, 1056 struct vm_area_struct *vma) 1057{ 1058 struct drm_device *dev = obj->dev; 1059 int ret; 1060 1061 /* Check for valid size. */ 1062 if (obj_size < vma->vm_end - vma->vm_start) 1063 return -EINVAL; 1064 1065 /* Take a ref for this mapping of the object, so that the fault 1066 * handler can dereference the mmap offset's pointer to the object. 1067 * This reference is cleaned up by the corresponding vm_close 1068 * (which should happen whether the vma was created by this call, or 1069 * by a vm_open due to mremap or partial unmap or whatever). 1070 */ 1071 drm_gem_object_get(obj); 1072 1073 vma->vm_private_data = obj; 1074 1075 if (obj->funcs && obj->funcs->mmap) { 1076 ret = obj->funcs->mmap(obj, vma); 1077 if (ret) { 1078 drm_gem_object_put(obj); 1079 return ret; 1080 } 1081 WARN_ON(!(vma->vm_flags & VM_DONTEXPAND)); 1082 } else { 1083 if (obj->funcs && obj->funcs->vm_ops) 1084 vma->vm_ops = obj->funcs->vm_ops; 1085 else if (dev->driver->gem_vm_ops) 1086 vma->vm_ops = dev->driver->gem_vm_ops; 1087 else { 1088 drm_gem_object_put(obj); 1089 return -EINVAL; 1090 } 1091 1092 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; 1093 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); 1094 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); 1095 } 1096 1097 return 0; 1098} 1099EXPORT_SYMBOL(drm_gem_mmap_obj); 1100 1101/** 1102 * drm_gem_mmap - memory map routine for GEM objects 1103 * @filp: DRM file pointer 1104 * @vma: VMA for the area to be mapped 1105 * 1106 * If a driver supports GEM object mapping, mmap calls on the DRM file 1107 * descriptor will end up here. 1108 * 1109 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will 1110 * contain the fake offset we created when the GTT map ioctl was called on 1111 * the object) and map it with a call to drm_gem_mmap_obj(). 1112 * 1113 * If the caller is not granted access to the buffer object, the mmap will fail 1114 * with EACCES. Please see the vma manager for more information. 1115 */ 1116int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) 1117{ 1118 struct drm_file *priv = filp->private_data; 1119 struct drm_device *dev = priv->minor->dev; 1120 struct drm_gem_object *obj = NULL; 1121 struct drm_vma_offset_node *node; 1122 int ret; 1123 1124 if (drm_dev_is_unplugged(dev)) 1125 return -ENODEV; 1126 1127 drm_vma_offset_lock_lookup(dev->vma_offset_manager); 1128 node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager, 1129 vma->vm_pgoff, 1130 vma_pages(vma)); 1131 if (likely(node)) { 1132 obj = container_of(node, struct drm_gem_object, vma_node); 1133 /* 1134 * When the object is being freed, after it hits 0-refcnt it 1135 * proceeds to tear down the object. In the process it will 1136 * attempt to remove the VMA offset and so acquire this 1137 * mgr->vm_lock. Therefore if we find an object with a 0-refcnt 1138 * that matches our range, we know it is in the process of being 1139 * destroyed and will be freed as soon as we release the lock - 1140 * so we have to check for the 0-refcnted object and treat it as 1141 * invalid. 1142 */ 1143 if (!kref_get_unless_zero(&obj->refcount)) 1144 obj = NULL; 1145 } 1146 drm_vma_offset_unlock_lookup(dev->vma_offset_manager); 1147 1148 if (!obj) 1149 return -EINVAL; 1150 1151 if (!drm_vma_node_is_allowed(node, priv)) { 1152 drm_gem_object_put(obj); 1153 return -EACCES; 1154 } 1155 1156 if (node->readonly) { 1157 if (vma->vm_flags & VM_WRITE) { 1158 drm_gem_object_put(obj); 1159 return -EINVAL; 1160 } 1161 1162 vma->vm_flags &= ~VM_MAYWRITE; 1163 } 1164 1165 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, 1166 vma); 1167 1168 drm_gem_object_put(obj); 1169 1170 return ret; 1171} 1172EXPORT_SYMBOL(drm_gem_mmap); 1173 1174void drm_gem_print_info(struct drm_printer *p, unsigned int indent, 1175 const struct drm_gem_object *obj) 1176{ 1177 drm_printf_indent(p, indent, "name=%d\n", obj->name); 1178 drm_printf_indent(p, indent, "refcount=%u\n", 1179 kref_read(&obj->refcount)); 1180 drm_printf_indent(p, indent, "start=%08lx\n", 1181 drm_vma_node_start(&obj->vma_node)); 1182 drm_printf_indent(p, indent, "size=%zu\n", obj->size); 1183 drm_printf_indent(p, indent, "imported=%s\n", 1184 obj->import_attach ? "yes" : "no"); 1185 1186 if (obj->funcs && obj->funcs->print_info) 1187 obj->funcs->print_info(p, indent, obj); 1188} 1189 1190int drm_gem_pin(struct drm_gem_object *obj) 1191{ 1192 if (obj->funcs && obj->funcs->pin) 1193 return obj->funcs->pin(obj); 1194 else if (obj->dev->driver->gem_prime_pin) 1195 return obj->dev->driver->gem_prime_pin(obj); 1196 else 1197 return 0; 1198} 1199 1200void drm_gem_unpin(struct drm_gem_object *obj) 1201{ 1202 if (obj->funcs && obj->funcs->unpin) 1203 obj->funcs->unpin(obj); 1204 else if (obj->dev->driver->gem_prime_unpin) 1205 obj->dev->driver->gem_prime_unpin(obj); 1206} 1207 1208void *drm_gem_vmap(struct drm_gem_object *obj) 1209{ 1210 void *vaddr; 1211 1212 if (obj->funcs && obj->funcs->vmap) 1213 vaddr = obj->funcs->vmap(obj); 1214 else if (obj->dev->driver->gem_prime_vmap) 1215 vaddr = obj->dev->driver->gem_prime_vmap(obj); 1216 else 1217 vaddr = ERR_PTR(-EOPNOTSUPP); 1218 1219 if (!vaddr) 1220 vaddr = ERR_PTR(-ENOMEM); 1221 1222 return vaddr; 1223} 1224 1225void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr) 1226{ 1227 if (!vaddr) 1228 return; 1229 1230 if (obj->funcs && obj->funcs->vunmap) 1231 obj->funcs->vunmap(obj, vaddr); 1232 else if (obj->dev->driver->gem_prime_vunmap) 1233 obj->dev->driver->gem_prime_vunmap(obj, vaddr); 1234} 1235 1236/** 1237 * drm_gem_lock_reservations - Sets up the ww context and acquires 1238 * the lock on an array of GEM objects. 1239 * 1240 * Once you've locked your reservations, you'll want to set up space 1241 * for your shared fences (if applicable), submit your job, then 1242 * drm_gem_unlock_reservations(). 1243 * 1244 * @objs: drm_gem_objects to lock 1245 * @count: Number of objects in @objs 1246 * @acquire_ctx: struct ww_acquire_ctx that will be initialized as 1247 * part of tracking this set of locked reservations. 1248 */ 1249int 1250drm_gem_lock_reservations(struct drm_gem_object **objs, int count, 1251 struct ww_acquire_ctx *acquire_ctx) 1252{ 1253 int contended = -1; 1254 int i, ret; 1255 1256 ww_acquire_init(acquire_ctx, &reservation_ww_class); 1257 1258retry: 1259 if (contended != -1) { 1260 struct drm_gem_object *obj = objs[contended]; 1261 1262 ret = dma_resv_lock_slow_interruptible(obj->resv, 1263 acquire_ctx); 1264 if (ret) { 1265 ww_acquire_fini(acquire_ctx); 1266 return ret; 1267 } 1268 } 1269 1270 for (i = 0; i < count; i++) { 1271 if (i == contended) 1272 continue; 1273 1274 ret = dma_resv_lock_interruptible(objs[i]->resv, 1275 acquire_ctx); 1276 if (ret) { 1277 int j; 1278 1279 for (j = 0; j < i; j++) 1280 dma_resv_unlock(objs[j]->resv); 1281 1282 if (contended != -1 && contended >= i) 1283 dma_resv_unlock(objs[contended]->resv); 1284 1285 if (ret == -EDEADLK) { 1286 contended = i; 1287 goto retry; 1288 } 1289 1290 ww_acquire_fini(acquire_ctx); 1291 return ret; 1292 } 1293 } 1294 1295 ww_acquire_done(acquire_ctx); 1296 1297 return 0; 1298} 1299EXPORT_SYMBOL(drm_gem_lock_reservations); 1300 1301void 1302drm_gem_unlock_reservations(struct drm_gem_object **objs, int count, 1303 struct ww_acquire_ctx *acquire_ctx) 1304{ 1305 int i; 1306 1307 for (i = 0; i < count; i++) 1308 dma_resv_unlock(objs[i]->resv); 1309 1310 ww_acquire_fini(acquire_ctx); 1311} 1312EXPORT_SYMBOL(drm_gem_unlock_reservations); 1313 1314/** 1315 * drm_gem_fence_array_add - Adds the fence to an array of fences to be 1316 * waited on, deduplicating fences from the same context. 1317 * 1318 * @fence_array: array of dma_fence * for the job to block on. 1319 * @fence: the dma_fence to add to the list of dependencies. 1320 * 1321 * Returns: 1322 * 0 on success, or an error on failing to expand the array. 1323 */ 1324int drm_gem_fence_array_add(struct xarray *fence_array, 1325 struct dma_fence *fence) 1326{ 1327 struct dma_fence *entry; 1328 unsigned long index; 1329 u32 id = 0; 1330 int ret; 1331 1332 if (!fence) 1333 return 0; 1334 1335 /* Deduplicate if we already depend on a fence from the same context. 1336 * This lets the size of the array of deps scale with the number of 1337 * engines involved, rather than the number of BOs. 1338 */ 1339 xa_for_each(fence_array, index, entry) { 1340 if (entry->context != fence->context) 1341 continue; 1342 1343 if (dma_fence_is_later(fence, entry)) { 1344 dma_fence_put(entry); 1345 xa_store(fence_array, index, fence, GFP_KERNEL); 1346 } else { 1347 dma_fence_put(fence); 1348 } 1349 return 0; 1350 } 1351 1352 ret = xa_alloc(fence_array, &id, fence, xa_limit_32b, GFP_KERNEL); 1353 if (ret != 0) 1354 dma_fence_put(fence); 1355 1356 return ret; 1357} 1358EXPORT_SYMBOL(drm_gem_fence_array_add); 1359 1360/** 1361 * drm_gem_fence_array_add_implicit - Adds the implicit dependencies tracked 1362 * in the GEM object's reservation object to an array of dma_fences for use in 1363 * scheduling a rendering job. 1364 * 1365 * This should be called after drm_gem_lock_reservations() on your array of 1366 * GEM objects used in the job but before updating the reservations with your 1367 * own fences. 1368 * 1369 * @fence_array: array of dma_fence * for the job to block on. 1370 * @obj: the gem object to add new dependencies from. 1371 * @write: whether the job might write the object (so we need to depend on 1372 * shared fences in the reservation object). 1373 */ 1374int drm_gem_fence_array_add_implicit(struct xarray *fence_array, 1375 struct drm_gem_object *obj, 1376 bool write) 1377{ 1378 int ret; 1379 struct dma_fence **fences; 1380 unsigned int i, fence_count; 1381 1382 if (!write) { 1383 struct dma_fence *fence = 1384 dma_resv_get_excl_rcu(obj->resv); 1385 1386 return drm_gem_fence_array_add(fence_array, fence); 1387 } 1388 1389 ret = dma_resv_get_fences_rcu(obj->resv, NULL, 1390 &fence_count, &fences); 1391 if (ret || !fence_count) 1392 return ret; 1393 1394 for (i = 0; i < fence_count; i++) { 1395 ret = drm_gem_fence_array_add(fence_array, fences[i]); 1396 if (ret) 1397 break; 1398 } 1399 1400 for (; i < fence_count; i++) 1401 dma_fence_put(fences[i]); 1402 kfree(fences); 1403 return ret; 1404} 1405EXPORT_SYMBOL(drm_gem_fence_array_add_implicit); 1406