1 /************************************************************************** 2 * 3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 24 * USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 /* 28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> 29 */ 30 31 #ifndef _TTM_BO_API_H_ 32 #define _TTM_BO_API_H_ 33 34 #include <drm/drmP.h> 35 #include <drm/drm_hashtab.h> 36 #include <drm/drm_vma_manager.h> 37 #include <linux/kref.h> 38 #include <linux/list.h> 39 #include <linux/wait.h> 40 #include <linux/mutex.h> 41 #include <linux/mm.h> 42 #include <linux/bitmap.h> 43 #include <linux/reservation.h> 44 45 struct ttm_bo_device; 46 47 struct drm_mm_node; 48 49 /** 50 * struct ttm_place 51 * 52 * @fpfn: first valid page frame number to put the object 53 * @lpfn: last valid page frame number to put the object 54 * @flags: memory domain and caching flags for the object 55 * 56 * Structure indicating a possible place to put an object. 57 */ 58 struct ttm_place { 59 unsigned fpfn; 60 unsigned lpfn; 61 uint32_t flags; 62 }; 63 64 /** 65 * struct ttm_placement 66 * 67 * @num_placement: number of preferred placements 68 * @placement: preferred placements 69 * @num_busy_placement: number of preferred placements when need to evict buffer 70 * @busy_placement: preferred placements when need to evict buffer 71 * 72 * Structure indicating the placement you request for an object. 73 */ 74 struct ttm_placement { 75 unsigned fpfn; 76 unsigned lpfn; 77 unsigned num_placement; 78 const struct ttm_place *placement; 79 unsigned num_busy_placement; 80 const struct ttm_place *busy_placement; 81 }; 82 83 /** 84 * struct ttm_bus_placement 85 * 86 * @addr: mapped virtual address 87 * @base: bus base address 88 * @is_iomem: is this io memory ? 89 * @size: size in byte 90 * @offset: offset from the base address 91 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count 92 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve 93 * 94 * Structure indicating the bus placement of an object. 95 */ 96 struct ttm_bus_placement { 97 void *addr; 98 unsigned long base; 99 unsigned long size; 100 unsigned long offset; 101 bool is_iomem; 102 bool io_reserved_vm; 103 uint64_t io_reserved_count; 104 }; 105 106 107 /** 108 * struct ttm_mem_reg 109 * 110 * @mm_node: Memory manager node. 111 * @size: Requested size of memory region. 112 * @num_pages: Actual size of memory region in pages. 113 * @page_alignment: Page alignment. 114 * @placement: Placement flags. 115 * @bus: Placement on io bus accessible to the CPU 116 * 117 * Structure indicating the placement and space resources used by a 118 * buffer object. 119 */ 120 121 struct ttm_mem_reg { 122 void *mm_node; 123 unsigned long start; 124 unsigned long size; 125 unsigned long num_pages; 126 uint32_t page_alignment; 127 uint32_t mem_type; 128 uint32_t placement; 129 struct ttm_bus_placement bus; 130 }; 131 132 /** 133 * enum ttm_bo_type 134 * 135 * @ttm_bo_type_device: These are 'normal' buffers that can 136 * be mmapped by user space. Each of these bos occupy a slot in the 137 * device address space, that can be used for normal vm operations. 138 * 139 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers, 140 * but they cannot be accessed from user-space. For kernel-only use. 141 * 142 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another 143 * driver. 144 */ 145 146 enum ttm_bo_type { 147 ttm_bo_type_device, 148 ttm_bo_type_kernel, 149 ttm_bo_type_sg 150 }; 151 152 struct ttm_tt; 153 154 /** 155 * struct ttm_buffer_object 156 * 157 * @bdev: Pointer to the buffer object device structure. 158 * @type: The bo type. 159 * @destroy: Destruction function. If NULL, kfree is used. 160 * @num_pages: Actual number of pages. 161 * @acc_size: Accounted size for this object. 162 * @kref: Reference count of this buffer object. When this refcount reaches 163 * zero, the object is put on the delayed delete list. 164 * @list_kref: List reference count of this buffer object. This member is 165 * used to avoid destruction while the buffer object is still on a list. 166 * Lru lists may keep one refcount, the delayed delete list, and kref != 0 167 * keeps one refcount. When this refcount reaches zero, 168 * the object is destroyed. 169 * @mem: structure describing current placement. 170 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 171 * pinned in physical memory. If this behaviour is not desired, this member 172 * holds a pointer to a persistent shmem object. 173 * @ttm: TTM structure holding system pages. 174 * @evicted: Whether the object was evicted without user-space knowing. 175 * @cpu_writes: For synchronization. Number of cpu writers. 176 * @lru: List head for the lru list. 177 * @ddestroy: List head for the delayed destroy list. 178 * @swap: List head for swap LRU list. 179 * @priv_flags: Flags describing buffer object internal state. 180 * @vma_node: Address space manager node. 181 * @offset: The current GPU offset, which can have different meanings 182 * depending on the memory type. For SYSTEM type memory, it should be 0. 183 * @cur_placement: Hint of current placement. 184 * @wu_mutex: Wait unreserved mutex. 185 * 186 * Base class for TTM buffer object, that deals with data placement and CPU 187 * mappings. GPU mappings are really up to the driver, but for simpler GPUs 188 * the driver can usually use the placement offset @offset directly as the 189 * GPU virtual address. For drivers implementing multiple 190 * GPU memory manager contexts, the driver should manage the address space 191 * in these contexts separately and use these objects to get the correct 192 * placement and caching for these GPU maps. This makes it possible to use 193 * these objects for even quite elaborate memory management schemes. 194 * The destroy member, the API visibility of this object makes it possible 195 * to derive driver specific types. 196 */ 197 198 struct ttm_buffer_object { 199 /** 200 * Members constant at init. 201 */ 202 203 struct ttm_bo_global *glob; 204 struct ttm_bo_device *bdev; 205 enum ttm_bo_type type; 206 void (*destroy) (struct ttm_buffer_object *); 207 unsigned long num_pages; 208 size_t acc_size; 209 210 /** 211 * Members not needing protection. 212 */ 213 214 struct kref kref; 215 struct kref list_kref; 216 217 /** 218 * Members protected by the bo::resv::reserved lock. 219 */ 220 221 struct ttm_mem_reg mem; 222 struct vm_object *persistent_swap_storage; 223 struct ttm_tt *ttm; 224 bool evicted; 225 226 /** 227 * Members protected by the bo::reserved lock only when written to. 228 */ 229 230 atomic_t cpu_writers; 231 232 /** 233 * Members protected by the bdev::lru_lock. 234 */ 235 236 struct list_head lru; 237 struct list_head ddestroy; 238 struct list_head swap; 239 struct list_head io_reserve_lru; 240 241 /** 242 * Members protected by a bo reservation. 243 */ 244 245 unsigned long priv_flags; 246 247 RB_ENTRY(ttm_buffer_object) vm_rb; /* DragonFly */ 248 struct drm_vma_offset_node vma_node; 249 250 /** 251 * Special members that are protected by the reserve lock 252 * and the bo::lock when written to. Can be read with 253 * either of these locks held. 254 */ 255 256 uint64_t offset; /* GPU address space is independent of CPU word size */ 257 uint32_t cur_placement; 258 259 struct sg_table *sg; 260 261 struct reservation_object *resv; 262 struct reservation_object ttm_resv; 263 struct lock wu_mutex; 264 }; 265 266 /** 267 * struct ttm_bo_kmap_obj 268 * 269 * @virtual: The current kernel virtual address. 270 * @page: The page when kmap'ing a single page. 271 * @bo_kmap_type: Type of bo_kmap. 272 * 273 * Object describing a kernel mapping. Since a TTM bo may be located 274 * in various memory types with various caching policies, the 275 * mapping can either be an ioremap, a vmap, a kmap or part of a 276 * premapped region. 277 */ 278 279 #define TTM_BO_MAP_IOMEM_MASK 0x80 280 struct ttm_bo_kmap_obj { 281 void *virtual; 282 struct page *page; 283 enum { 284 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK, 285 ttm_bo_map_vmap = 2, 286 ttm_bo_map_kmap = 3, 287 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK, 288 } bo_kmap_type; 289 struct ttm_buffer_object *bo; 290 }; 291 292 /** 293 * ttm_bo_reference - reference a struct ttm_buffer_object 294 * 295 * @bo: The buffer object. 296 * 297 * Returns a refcounted pointer to a buffer object. 298 */ 299 300 static inline struct ttm_buffer_object * 301 ttm_bo_reference(struct ttm_buffer_object *bo) 302 { 303 kref_get(&bo->kref); 304 return bo; 305 } 306 307 /** 308 * ttm_bo_wait - wait for buffer idle. 309 * 310 * @bo: The buffer object. 311 * @interruptible: Use interruptible wait. 312 * @no_wait: Return immediately if buffer is busy. 313 * 314 * This function must be called with the bo::mutex held, and makes 315 * sure any previous rendering to the buffer is completed. 316 * Note: It might be necessary to block validations before the 317 * wait by reserving the buffer. 318 * Returns -EBUSY if no_wait is true and the buffer is busy. 319 * Returns -ERESTARTSYS if interrupted by a signal. 320 */ 321 extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy, 322 bool interruptible, bool no_wait); 323 324 /** 325 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo 326 * 327 * @placement: Return immediately if buffer is busy. 328 * @mem: The struct ttm_mem_reg indicating the region where the bo resides 329 * @new_flags: Describes compatible placement found 330 * 331 * Returns true if the placement is compatible 332 */ 333 extern bool ttm_bo_mem_compat(struct ttm_placement *placement, 334 struct ttm_mem_reg *mem, 335 uint32_t *new_flags); 336 337 /** 338 * ttm_bo_validate 339 * 340 * @bo: The buffer object. 341 * @placement: Proposed placement for the buffer object. 342 * @interruptible: Sleep interruptible if sleeping. 343 * @no_wait_gpu: Return immediately if the GPU is busy. 344 * 345 * Changes placement and caching policy of the buffer object 346 * according proposed placement. 347 * Returns 348 * -EINVAL on invalid proposed placement. 349 * -ENOMEM on out-of-memory condition. 350 * -EBUSY if no_wait is true and buffer busy. 351 * -ERESTARTSYS if interrupted by a signal. 352 */ 353 extern int ttm_bo_validate(struct ttm_buffer_object *bo, 354 struct ttm_placement *placement, 355 bool interruptible, 356 bool no_wait_gpu); 357 358 /** 359 * ttm_bo_unref 360 * 361 * @bo: The buffer object. 362 * 363 * Unreference and clear a pointer to a buffer object. 364 */ 365 extern void ttm_bo_unref(struct ttm_buffer_object **bo); 366 367 368 /** 369 * ttm_bo_list_ref_sub 370 * 371 * @bo: The buffer object. 372 * @count: The number of references with which to decrease @bo::list_kref; 373 * @never_free: The refcount should not reach zero with this operation. 374 * 375 * Release @count lru list references to this buffer object. 376 */ 377 extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count, 378 bool never_free); 379 380 /** 381 * ttm_bo_add_to_lru 382 * 383 * @bo: The buffer object. 384 * 385 * Add this bo to the relevant mem type lru and, if it's backed by 386 * system pages (ttms) to the swap list. 387 * This function must be called with struct ttm_bo_global::lru_lock held, and 388 * is typically called immediately prior to unreserving a bo. 389 */ 390 extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo); 391 392 /** 393 * ttm_bo_del_from_lru 394 * 395 * @bo: The buffer object. 396 * 397 * Remove this bo from all lru lists used to lookup and reserve an object. 398 * This function must be called with struct ttm_bo_global::lru_lock held, 399 * and is usually called just immediately after the bo has been reserved to 400 * avoid recursive reservation from lru lists. 401 */ 402 extern int ttm_bo_del_from_lru(struct ttm_buffer_object *bo); 403 404 405 /** 406 * ttm_bo_lock_delayed_workqueue 407 * 408 * Prevent the delayed workqueue from running. 409 * Returns 410 * True if the workqueue was queued at the time 411 */ 412 extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev); 413 414 /** 415 * ttm_bo_unlock_delayed_workqueue 416 * 417 * Allows the delayed workqueue to run. 418 */ 419 extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, 420 int resched); 421 422 /** 423 * ttm_bo_synccpu_write_grab 424 * 425 * @bo: The buffer object: 426 * @no_wait: Return immediately if buffer is busy. 427 * 428 * Synchronizes a buffer object for CPU RW access. This means 429 * command submission that affects the buffer will return -EBUSY 430 * until ttm_bo_synccpu_write_release is called. 431 * 432 * Returns 433 * -EBUSY if the buffer is busy and no_wait is true. 434 * -ERESTARTSYS if interrupted by a signal. 435 */ 436 extern int 437 ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait); 438 439 /** 440 * ttm_bo_synccpu_write_release: 441 * 442 * @bo : The buffer object. 443 * 444 * Releases a synccpu lock. 445 */ 446 extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo); 447 448 /** 449 * ttm_bo_acc_size 450 * 451 * @bdev: Pointer to a ttm_bo_device struct. 452 * @bo_size: size of the buffer object in byte. 453 * @struct_size: size of the structure holding buffer object datas 454 * 455 * Returns size to account for a buffer object 456 */ 457 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev, 458 unsigned long bo_size, 459 unsigned struct_size); 460 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev, 461 unsigned long bo_size, 462 unsigned struct_size); 463 464 /** 465 * ttm_bo_init 466 * 467 * @bdev: Pointer to a ttm_bo_device struct. 468 * @bo: Pointer to a ttm_buffer_object to be initialized. 469 * @size: Requested size of buffer object. 470 * @type: Requested type of buffer object. 471 * @flags: Initial placement flags. 472 * @page_alignment: Data alignment in pages. 473 * @interruptible: If needing to sleep to wait for GPU resources, 474 * sleep interruptible. 475 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 476 * pinned in physical memory. If this behaviour is not desired, this member 477 * holds a pointer to a persistent shmem object. Typically, this would 478 * point to the shmem object backing a GEM object if TTM is used to back a 479 * GEM user interface. 480 * @acc_size: Accounted size for this object. 481 * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one. 482 * @destroy: Destroy function. Use NULL for kfree(). 483 * 484 * This function initializes a pre-allocated struct ttm_buffer_object. 485 * As this object may be part of a larger structure, this function, 486 * together with the @destroy function, 487 * enables driver-specific objects derived from a ttm_buffer_object. 488 * On successful return, the object kref and list_kref are set to 1. 489 * If a failure occurs, the function will call the @destroy function, or 490 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is 491 * illegal and will likely cause memory corruption. 492 * 493 * Returns 494 * -ENOMEM: Out of memory. 495 * -EINVAL: Invalid placement flags. 496 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 497 */ 498 499 extern int ttm_bo_init(struct ttm_bo_device *bdev, 500 struct ttm_buffer_object *bo, 501 unsigned long size, 502 enum ttm_bo_type type, 503 struct ttm_placement *placement, 504 uint32_t page_alignment, 505 bool interrubtible, 506 struct vm_object *persistent_swap_storage, 507 size_t acc_size, 508 struct sg_table *sg, 509 struct reservation_object *resv, 510 void (*destroy) (struct ttm_buffer_object *)); 511 512 /** 513 * ttm_bo_create 514 * 515 * @bdev: Pointer to a ttm_bo_device struct. 516 * @size: Requested size of buffer object. 517 * @type: Requested type of buffer object. 518 * @placement: Initial placement. 519 * @page_alignment: Data alignment in pages. 520 * @interruptible: If needing to sleep while waiting for GPU resources, 521 * sleep interruptible. 522 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 523 * pinned in physical memory. If this behaviour is not desired, this member 524 * holds a pointer to a persistent shmem object. Typically, this would 525 * point to the shmem object backing a GEM object if TTM is used to back a 526 * GEM user interface. 527 * @p_bo: On successful completion *p_bo points to the created object. 528 * 529 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init 530 * on that object. The destroy function is set to kfree(). 531 * Returns 532 * -ENOMEM: Out of memory. 533 * -EINVAL: Invalid placement flags. 534 * -ERESTARTSYS: Interrupted by signal while waiting for resources. 535 */ 536 537 extern int ttm_bo_create(struct ttm_bo_device *bdev, 538 unsigned long size, 539 enum ttm_bo_type type, 540 struct ttm_placement *placement, 541 uint32_t page_alignment, 542 bool interruptible, 543 struct vm_object *persistent_swap_storage, 544 struct ttm_buffer_object **p_bo); 545 546 /** 547 * ttm_bo_init_mm 548 * 549 * @bdev: Pointer to a ttm_bo_device struct. 550 * @mem_type: The memory type. 551 * @p_size: size managed area in pages. 552 * 553 * Initialize a manager for a given memory type. 554 * Note: if part of driver firstopen, it must be protected from a 555 * potentially racing lastclose. 556 * Returns: 557 * -EINVAL: invalid size or memory type. 558 * -ENOMEM: Not enough memory. 559 * May also return driver-specified errors. 560 */ 561 562 extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type, 563 unsigned long p_size); 564 /** 565 * ttm_bo_clean_mm 566 * 567 * @bdev: Pointer to a ttm_bo_device struct. 568 * @mem_type: The memory type. 569 * 570 * Take down a manager for a given memory type after first walking 571 * the LRU list to evict any buffers left alive. 572 * 573 * Normally, this function is part of lastclose() or unload(), and at that 574 * point there shouldn't be any buffers left created by user-space, since 575 * there should've been removed by the file descriptor release() method. 576 * However, before this function is run, make sure to signal all sync objects, 577 * and verify that the delayed delete queue is empty. The driver must also 578 * make sure that there are no NO_EVICT buffers present in this memory type 579 * when the call is made. 580 * 581 * If this function is part of a VT switch, the caller must make sure that 582 * there are no appications currently validating buffers before this 583 * function is called. The caller can do that by first taking the 584 * struct ttm_bo_device::ttm_lock in write mode. 585 * 586 * Returns: 587 * -EINVAL: invalid or uninitialized memory type. 588 * -EBUSY: There are still buffers left in this memory type. 589 */ 590 591 extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type); 592 593 /** 594 * ttm_bo_evict_mm 595 * 596 * @bdev: Pointer to a ttm_bo_device struct. 597 * @mem_type: The memory type. 598 * 599 * Evicts all buffers on the lru list of the memory type. 600 * This is normally part of a VT switch or an 601 * out-of-memory-space-due-to-fragmentation handler. 602 * The caller must make sure that there are no other processes 603 * currently validating buffers, and can do that by taking the 604 * struct ttm_bo_device::ttm_lock in write mode. 605 * 606 * Returns: 607 * -EINVAL: Invalid or uninitialized memory type. 608 * -ERESTARTSYS: The call was interrupted by a signal while waiting to 609 * evict a buffer. 610 */ 611 612 extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type); 613 614 /** 615 * ttm_kmap_obj_virtual 616 * 617 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap. 618 * @is_iomem: Pointer to an integer that on return indicates 1 if the 619 * virtual map is io memory, 0 if normal memory. 620 * 621 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap. 622 * If *is_iomem is 1 on return, the virtual address points to an io memory area, 623 * that should strictly be accessed by the iowriteXX() and similar functions. 624 */ 625 626 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, 627 bool *is_iomem) 628 { 629 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK); 630 return map->virtual; 631 } 632 633 /** 634 * ttm_bo_kmap 635 * 636 * @bo: The buffer object. 637 * @start_page: The first page to map. 638 * @num_pages: Number of pages to map. 639 * @map: pointer to a struct ttm_bo_kmap_obj representing the map. 640 * 641 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the 642 * data in the buffer object. The ttm_kmap_obj_virtual function can then be 643 * used to obtain a virtual address to the data. 644 * 645 * Returns 646 * -ENOMEM: Out of memory. 647 * -EINVAL: Invalid range. 648 */ 649 650 extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, 651 unsigned long num_pages, struct ttm_bo_kmap_obj *map); 652 653 /** 654 * ttm_bo_kunmap 655 * 656 * @map: Object describing the map to unmap. 657 * 658 * Unmaps a kernel map set up by ttm_bo_kmap. 659 */ 660 661 extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); 662 663 /** 664 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object. 665 * 666 * @vma: vma as input from the fbdev mmap method. 667 * @bo: The bo backing the address space. The address space will 668 * have the same size as the bo, and start at offset 0. 669 * 670 * This function is intended to be called by the fbdev mmap method 671 * if the fbdev address space is to be backed by a bo. 672 */ 673 674 extern int ttm_fbdev_mmap(struct vm_area_struct *vma, 675 struct ttm_buffer_object *bo); 676 677 /** 678 * ttm_bo_mmap - mmap out of the ttm device address space. 679 * 680 * @filp: filp as input from the mmap method. 681 * @vma: vma as input from the mmap method. 682 * @bdev: Pointer to the ttm_bo_device with the address space manager. 683 * 684 * This function is intended to be called by the device mmap method. 685 * if the device address space is to be backed by the bo manager. 686 */ 687 688 extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, 689 struct ttm_bo_device *bdev); 690 691 /** 692 * ttm_bo_io 693 * 694 * @bdev: Pointer to the struct ttm_bo_device. 695 * @filp: Pointer to the struct file attempting to read / write. 696 * @wbuf: User-space pointer to address of buffer to write. NULL on read. 697 * @rbuf: User-space pointer to address of buffer to read into. 698 * Null on write. 699 * @count: Number of bytes to read / write. 700 * @f_pos: Pointer to current file position. 701 * @write: 1 for read, 0 for write. 702 * 703 * This function implements read / write into ttm buffer objects, and is 704 * intended to 705 * be called from the fops::read and fops::write method. 706 * Returns: 707 * See man (2) write, man(2) read. In particular, 708 * the function may return -ERESTARTSYS if 709 * interrupted by a signal. 710 */ 711 712 extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp, 713 const char __user *wbuf, char __user *rbuf, 714 size_t count, loff_t *f_pos, bool write); 715 716 extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev); 717 extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo); 718 #endif 719