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/drm_hashtab.h> 35#include <drm/drm_vma_manager.h> 36#include <linux/kref.h> 37#include <linux/list.h> 38#include <linux/wait.h> 39#include <linux/mutex.h> 40#include <linux/mm.h> 41#include <linux/bitmap.h> 42#include <linux/reservation.h> 43 44struct ttm_bo_global; 45 46struct ttm_bo_device; 47 48struct drm_mm_node; 49 50struct ttm_placement; 51 52struct ttm_place; 53 54/** 55 * struct ttm_bus_placement 56 * 57 * @addr: mapped virtual address 58 * @base: bus base address 59 * @is_iomem: is this io memory ? 60 * @size: size in byte 61 * @offset: offset from the base address 62 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count 63 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve 64 * 65 * Structure indicating the bus placement of an object. 66 */ 67struct ttm_bus_placement { 68 void *addr; 69 phys_addr_t base; 70 unsigned long size; 71 unsigned long offset; 72 bool is_iomem; 73 bool io_reserved_vm; 74 uint64_t io_reserved_count; 75}; 76 77 78/** 79 * struct ttm_mem_reg 80 * 81 * @mm_node: Memory manager node. 82 * @size: Requested size of memory region. 83 * @num_pages: Actual size of memory region in pages. 84 * @page_alignment: Page alignment. 85 * @placement: Placement flags. 86 * @bus: Placement on io bus accessible to the CPU 87 * 88 * Structure indicating the placement and space resources used by a 89 * buffer object. 90 */ 91 92struct ttm_mem_reg { 93 void *mm_node; 94 unsigned long start; 95 unsigned long size; 96 unsigned long num_pages; 97 uint32_t page_alignment; 98 uint32_t mem_type; 99 uint32_t placement; 100 struct ttm_bus_placement bus; 101}; 102 103/** 104 * enum ttm_bo_type 105 * 106 * @ttm_bo_type_device: These are 'normal' buffers that can 107 * be mmapped by user space. Each of these bos occupy a slot in the 108 * device address space, that can be used for normal vm operations. 109 * 110 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers, 111 * but they cannot be accessed from user-space. For kernel-only use. 112 * 113 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another 114 * driver. 115 */ 116 117enum ttm_bo_type { 118 ttm_bo_type_device, 119 ttm_bo_type_kernel, 120 ttm_bo_type_sg 121}; 122 123struct ttm_tt; 124 125/** 126 * struct ttm_buffer_object 127 * 128 * @bdev: Pointer to the buffer object device structure. 129 * @type: The bo type. 130 * @destroy: Destruction function. If NULL, kfree is used. 131 * @num_pages: Actual number of pages. 132 * @acc_size: Accounted size for this object. 133 * @kref: Reference count of this buffer object. When this refcount reaches 134 * zero, the object is put on the delayed delete list. 135 * @list_kref: List reference count of this buffer object. This member is 136 * used to avoid destruction while the buffer object is still on a list. 137 * Lru lists may keep one refcount, the delayed delete list, and kref != 0 138 * keeps one refcount. When this refcount reaches zero, 139 * the object is destroyed. 140 * @mem: structure describing current placement. 141 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 142 * pinned in physical memory. If this behaviour is not desired, this member 143 * holds a pointer to a persistent shmem object. 144 * @ttm: TTM structure holding system pages. 145 * @evicted: Whether the object was evicted without user-space knowing. 146 * @cpu_writes: For synchronization. Number of cpu writers. 147 * @lru: List head for the lru list. 148 * @ddestroy: List head for the delayed destroy list. 149 * @swap: List head for swap LRU list. 150 * @moving: Fence set when BO is moving 151 * @vma_node: Address space manager node. 152 * @offset: The current GPU offset, which can have different meanings 153 * depending on the memory type. For SYSTEM type memory, it should be 0. 154 * @cur_placement: Hint of current placement. 155 * @wu_mutex: Wait unreserved mutex. 156 * 157 * Base class for TTM buffer object, that deals with data placement and CPU 158 * mappings. GPU mappings are really up to the driver, but for simpler GPUs 159 * the driver can usually use the placement offset @offset directly as the 160 * GPU virtual address. For drivers implementing multiple 161 * GPU memory manager contexts, the driver should manage the address space 162 * in these contexts separately and use these objects to get the correct 163 * placement and caching for these GPU maps. This makes it possible to use 164 * these objects for even quite elaborate memory management schemes. 165 * The destroy member, the API visibility of this object makes it possible 166 * to derive driver specific types. 167 */ 168 169struct ttm_buffer_object { 170 /** 171 * Members constant at init. 172 */ 173 174 struct ttm_bo_device *bdev; 175 enum ttm_bo_type type; 176 void (*destroy) (struct ttm_buffer_object *); 177 unsigned long num_pages; 178 size_t acc_size; 179 180 /** 181 * Members not needing protection. 182 */ 183 184 struct kref kref; 185 struct kref list_kref; 186 187 /** 188 * Members protected by the bo::resv::reserved lock. 189 */ 190 191 struct ttm_mem_reg mem; 192 struct file *persistent_swap_storage; 193 struct ttm_tt *ttm; 194 bool evicted; 195 196 /** 197 * Members protected by the bo::reserved lock only when written to. 198 */ 199 200 atomic_t cpu_writers; 201 202 /** 203 * Members protected by the bdev::lru_lock. 204 */ 205 206 struct list_head lru; 207 struct list_head ddestroy; 208 struct list_head swap; 209 struct list_head io_reserve_lru; 210 211 /** 212 * Members protected by a bo reservation. 213 */ 214 215 struct dma_fence *moving; 216 217 struct drm_vma_offset_node vma_node; 218 219 unsigned priority; 220 221 /** 222 * Special members that are protected by the reserve lock 223 * and the bo::lock when written to. Can be read with 224 * either of these locks held. 225 */ 226 227 uint64_t offset; /* GPU address space is independent of CPU word size */ 228 229 struct sg_table *sg; 230 231 struct reservation_object *resv; 232 struct reservation_object ttm_resv; 233 struct mutex wu_mutex; 234}; 235 236/** 237 * struct ttm_bo_kmap_obj 238 * 239 * @virtual: The current kernel virtual address. 240 * @page: The page when kmap'ing a single page. 241 * @bo_kmap_type: Type of bo_kmap. 242 * 243 * Object describing a kernel mapping. Since a TTM bo may be located 244 * in various memory types with various caching policies, the 245 * mapping can either be an ioremap, a vmap, a kmap or part of a 246 * premapped region. 247 */ 248 249#define TTM_BO_MAP_IOMEM_MASK 0x80 250struct ttm_bo_kmap_obj { 251 void *virtual; 252 struct page *page; 253 enum { 254 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK, 255 ttm_bo_map_vmap = 2, 256 ttm_bo_map_kmap = 3, 257 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK, 258 } bo_kmap_type; 259 struct ttm_buffer_object *bo; 260}; 261 262/** 263 * struct ttm_operation_ctx 264 * 265 * @interruptible: Sleep interruptible if sleeping. 266 * @no_wait_gpu: Return immediately if the GPU is busy. 267 * @resv: Reservation object to allow reserved evictions with. 268 * @flags: Including the following flags 269 * 270 * Context for TTM operations like changing buffer placement or general memory 271 * allocation. 272 */ 273struct ttm_operation_ctx { 274 bool interruptible; 275 bool no_wait_gpu; 276 struct reservation_object *resv; 277 uint64_t bytes_moved; 278 uint32_t flags; 279}; 280 281/* Allow eviction of reserved BOs */ 282#define TTM_OPT_FLAG_ALLOW_RES_EVICT 0x1 283/* when serving page fault or suspend, allow alloc anyway */ 284#define TTM_OPT_FLAG_FORCE_ALLOC 0x2 285 286/** 287 * ttm_bo_reference - reference a struct ttm_buffer_object 288 * 289 * @bo: The buffer object. 290 * 291 * Returns a refcounted pointer to a buffer object. 292 */ 293 294static inline struct ttm_buffer_object * 295ttm_bo_reference(struct ttm_buffer_object *bo) 296{ 297 kref_get(&bo->kref); 298 return bo; 299} 300 301/** 302 * ttm_bo_wait - wait for buffer idle. 303 * 304 * @bo: The buffer object. 305 * @interruptible: Use interruptible wait. 306 * @no_wait: Return immediately if buffer is busy. 307 * 308 * This function must be called with the bo::mutex held, and makes 309 * sure any previous rendering to the buffer is completed. 310 * Note: It might be necessary to block validations before the 311 * wait by reserving the buffer. 312 * Returns -EBUSY if no_wait is true and the buffer is busy. 313 * Returns -ERESTARTSYS if interrupted by a signal. 314 */ 315int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait); 316 317/** 318 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo 319 * 320 * @placement: Return immediately if buffer is busy. 321 * @mem: The struct ttm_mem_reg indicating the region where the bo resides 322 * @new_flags: Describes compatible placement found 323 * 324 * Returns true if the placement is compatible 325 */ 326bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_mem_reg *mem, 327 uint32_t *new_flags); 328 329/** 330 * ttm_bo_validate 331 * 332 * @bo: The buffer object. 333 * @placement: Proposed placement for the buffer object. 334 * @ctx: validation parameters. 335 * 336 * Changes placement and caching policy of the buffer object 337 * according proposed placement. 338 * Returns 339 * -EINVAL on invalid proposed placement. 340 * -ENOMEM on out-of-memory condition. 341 * -EBUSY if no_wait is true and buffer busy. 342 * -ERESTARTSYS if interrupted by a signal. 343 */ 344int ttm_bo_validate(struct ttm_buffer_object *bo, 345 struct ttm_placement *placement, 346 struct ttm_operation_ctx *ctx); 347 348/** 349 * ttm_bo_unref 350 * 351 * @bo: The buffer object. 352 * 353 * Unreference and clear a pointer to a buffer object. 354 */ 355void ttm_bo_unref(struct ttm_buffer_object **bo); 356 357/** 358 * ttm_bo_add_to_lru 359 * 360 * @bo: The buffer object. 361 * 362 * Add this bo to the relevant mem type lru and, if it's backed by 363 * system pages (ttms) to the swap list. 364 * This function must be called with struct ttm_bo_global::lru_lock held, and 365 * is typically called immediately prior to unreserving a bo. 366 */ 367void ttm_bo_add_to_lru(struct ttm_buffer_object *bo); 368 369/** 370 * ttm_bo_del_from_lru 371 * 372 * @bo: The buffer object. 373 * 374 * Remove this bo from all lru lists used to lookup and reserve an object. 375 * This function must be called with struct ttm_bo_global::lru_lock held, 376 * and is usually called just immediately after the bo has been reserved to 377 * avoid recursive reservation from lru lists. 378 */ 379void ttm_bo_del_from_lru(struct ttm_buffer_object *bo); 380 381/** 382 * ttm_bo_move_to_lru_tail 383 * 384 * @bo: The buffer object. 385 * 386 * Move this BO to the tail of all lru lists used to lookup and reserve an 387 * object. This function must be called with struct ttm_bo_global::lru_lock 388 * held, and is used to make a BO less likely to be considered for eviction. 389 */ 390void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo); 391 392/** 393 * ttm_bo_lock_delayed_workqueue 394 * 395 * Prevent the delayed workqueue from running. 396 * Returns 397 * True if the workqueue was queued at the time 398 */ 399int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev); 400 401/** 402 * ttm_bo_unlock_delayed_workqueue 403 * 404 * Allows the delayed workqueue to run. 405 */ 406void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched); 407 408/** 409 * ttm_bo_eviction_valuable 410 * 411 * @bo: The buffer object to evict 412 * @place: the placement we need to make room for 413 * 414 * Check if it is valuable to evict the BO to make room for the given placement. 415 */ 416bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo, 417 const struct ttm_place *place); 418 419/** 420 * ttm_bo_synccpu_write_grab 421 * 422 * @bo: The buffer object: 423 * @no_wait: Return immediately if buffer is busy. 424 * 425 * Synchronizes a buffer object for CPU RW access. This means 426 * command submission that affects the buffer will return -EBUSY 427 * until ttm_bo_synccpu_write_release is called. 428 * 429 * Returns 430 * -EBUSY if the buffer is busy and no_wait is true. 431 * -ERESTARTSYS if interrupted by a signal. 432 */ 433int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait); 434 435/** 436 * ttm_bo_synccpu_write_release: 437 * 438 * @bo : The buffer object. 439 * 440 * Releases a synccpu lock. 441 */ 442void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo); 443 444/** 445 * ttm_bo_acc_size 446 * 447 * @bdev: Pointer to a ttm_bo_device struct. 448 * @bo_size: size of the buffer object in byte. 449 * @struct_size: size of the structure holding buffer object datas 450 * 451 * Returns size to account for a buffer object 452 */ 453size_t ttm_bo_acc_size(struct ttm_bo_device *bdev, 454 unsigned long bo_size, 455 unsigned struct_size); 456size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev, 457 unsigned long bo_size, 458 unsigned struct_size); 459 460/** 461 * ttm_bo_init_reserved 462 * 463 * @bdev: Pointer to a ttm_bo_device struct. 464 * @bo: Pointer to a ttm_buffer_object to be initialized. 465 * @size: Requested size of buffer object. 466 * @type: Requested type of buffer object. 467 * @flags: Initial placement flags. 468 * @page_alignment: Data alignment in pages. 469 * @ctx: TTM operation context for memory allocation. 470 * @acc_size: Accounted size for this object. 471 * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one. 472 * @destroy: Destroy function. Use NULL for kfree(). 473 * 474 * This function initializes a pre-allocated struct ttm_buffer_object. 475 * As this object may be part of a larger structure, this function, 476 * together with the @destroy function, 477 * enables driver-specific objects derived from a ttm_buffer_object. 478 * 479 * On successful return, the caller owns an object kref to @bo. The kref and 480 * list_kref are usually set to 1, but note that in some situations, other 481 * tasks may already be holding references to @bo as well. 482 * Furthermore, if resv == NULL, the buffer's reservation lock will be held, 483 * and it is the caller's responsibility to call ttm_bo_unreserve. 484 * 485 * If a failure occurs, the function will call the @destroy function, or 486 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is 487 * illegal and will likely cause memory corruption. 488 * 489 * Returns 490 * -ENOMEM: Out of memory. 491 * -EINVAL: Invalid placement flags. 492 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 493 */ 494 495int ttm_bo_init_reserved(struct ttm_bo_device *bdev, 496 struct ttm_buffer_object *bo, 497 unsigned long size, 498 enum ttm_bo_type type, 499 struct ttm_placement *placement, 500 uint32_t page_alignment, 501 struct ttm_operation_ctx *ctx, 502 size_t acc_size, 503 struct sg_table *sg, 504 struct reservation_object *resv, 505 void (*destroy) (struct ttm_buffer_object *)); 506 507/** 508 * ttm_bo_init 509 * 510 * @bdev: Pointer to a ttm_bo_device struct. 511 * @bo: Pointer to a ttm_buffer_object to be initialized. 512 * @size: Requested size of buffer object. 513 * @type: Requested type of buffer object. 514 * @flags: Initial placement flags. 515 * @page_alignment: Data alignment in pages. 516 * @interruptible: If needing to sleep to wait for GPU resources, 517 * sleep interruptible. 518 * pinned in physical memory. If this behaviour is not desired, this member 519 * holds a pointer to a persistent shmem object. Typically, this would 520 * point to the shmem object backing a GEM object if TTM is used to back a 521 * GEM user interface. 522 * @acc_size: Accounted size for this object. 523 * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one. 524 * @destroy: Destroy function. Use NULL for kfree(). 525 * 526 * This function initializes a pre-allocated struct ttm_buffer_object. 527 * As this object may be part of a larger structure, this function, 528 * together with the @destroy function, 529 * enables driver-specific objects derived from a ttm_buffer_object. 530 * 531 * On successful return, the caller owns an object kref to @bo. The kref and 532 * list_kref are usually set to 1, but note that in some situations, other 533 * tasks may already be holding references to @bo as well. 534 * 535 * If a failure occurs, the function will call the @destroy function, or 536 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is 537 * illegal and will likely cause memory corruption. 538 * 539 * Returns 540 * -ENOMEM: Out of memory. 541 * -EINVAL: Invalid placement flags. 542 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 543 */ 544int ttm_bo_init(struct ttm_bo_device *bdev, struct ttm_buffer_object *bo, 545 unsigned long size, enum ttm_bo_type type, 546 struct ttm_placement *placement, 547 uint32_t page_alignment, bool interrubtible, size_t acc_size, 548 struct sg_table *sg, struct reservation_object *resv, 549 void (*destroy) (struct ttm_buffer_object *)); 550 551/** 552 * ttm_bo_create 553 * 554 * @bdev: Pointer to a ttm_bo_device struct. 555 * @size: Requested size of buffer object. 556 * @type: Requested type of buffer object. 557 * @placement: Initial placement. 558 * @page_alignment: Data alignment in pages. 559 * @interruptible: If needing to sleep while waiting for GPU resources, 560 * sleep interruptible. 561 * @p_bo: On successful completion *p_bo points to the created object. 562 * 563 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init 564 * on that object. The destroy function is set to kfree(). 565 * Returns 566 * -ENOMEM: Out of memory. 567 * -EINVAL: Invalid placement flags. 568 * -ERESTARTSYS: Interrupted by signal while waiting for resources. 569 */ 570int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size, 571 enum ttm_bo_type type, struct ttm_placement *placement, 572 uint32_t page_alignment, bool interruptible, 573 struct ttm_buffer_object **p_bo); 574 575/** 576 * ttm_bo_init_mm 577 * 578 * @bdev: Pointer to a ttm_bo_device struct. 579 * @mem_type: The memory type. 580 * @p_size: size managed area in pages. 581 * 582 * Initialize a manager for a given memory type. 583 * Note: if part of driver firstopen, it must be protected from a 584 * potentially racing lastclose. 585 * Returns: 586 * -EINVAL: invalid size or memory type. 587 * -ENOMEM: Not enough memory. 588 * May also return driver-specified errors. 589 */ 590int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type, 591 unsigned long p_size); 592 593/** 594 * ttm_bo_clean_mm 595 * 596 * @bdev: Pointer to a ttm_bo_device struct. 597 * @mem_type: The memory type. 598 * 599 * Take down a manager for a given memory type after first walking 600 * the LRU list to evict any buffers left alive. 601 * 602 * Normally, this function is part of lastclose() or unload(), and at that 603 * point there shouldn't be any buffers left created by user-space, since 604 * there should've been removed by the file descriptor release() method. 605 * However, before this function is run, make sure to signal all sync objects, 606 * and verify that the delayed delete queue is empty. The driver must also 607 * make sure that there are no NO_EVICT buffers present in this memory type 608 * when the call is made. 609 * 610 * If this function is part of a VT switch, the caller must make sure that 611 * there are no appications currently validating buffers before this 612 * function is called. The caller can do that by first taking the 613 * struct ttm_bo_device::ttm_lock in write mode. 614 * 615 * Returns: 616 * -EINVAL: invalid or uninitialized memory type. 617 * -EBUSY: There are still buffers left in this memory type. 618 */ 619int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type); 620 621/** 622 * ttm_bo_evict_mm 623 * 624 * @bdev: Pointer to a ttm_bo_device struct. 625 * @mem_type: The memory type. 626 * 627 * Evicts all buffers on the lru list of the memory type. 628 * This is normally part of a VT switch or an 629 * out-of-memory-space-due-to-fragmentation handler. 630 * The caller must make sure that there are no other processes 631 * currently validating buffers, and can do that by taking the 632 * struct ttm_bo_device::ttm_lock in write mode. 633 * 634 * Returns: 635 * -EINVAL: Invalid or uninitialized memory type. 636 * -ERESTARTSYS: The call was interrupted by a signal while waiting to 637 * evict a buffer. 638 */ 639int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type); 640 641/** 642 * ttm_kmap_obj_virtual 643 * 644 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap. 645 * @is_iomem: Pointer to an integer that on return indicates 1 if the 646 * virtual map is io memory, 0 if normal memory. 647 * 648 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap. 649 * If *is_iomem is 1 on return, the virtual address points to an io memory area, 650 * that should strictly be accessed by the iowriteXX() and similar functions. 651 */ 652static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, 653 bool *is_iomem) 654{ 655 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK); 656 return map->virtual; 657} 658 659/** 660 * ttm_bo_kmap 661 * 662 * @bo: The buffer object. 663 * @start_page: The first page to map. 664 * @num_pages: Number of pages to map. 665 * @map: pointer to a struct ttm_bo_kmap_obj representing the map. 666 * 667 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the 668 * data in the buffer object. The ttm_kmap_obj_virtual function can then be 669 * used to obtain a virtual address to the data. 670 * 671 * Returns 672 * -ENOMEM: Out of memory. 673 * -EINVAL: Invalid range. 674 */ 675int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, 676 unsigned long num_pages, struct ttm_bo_kmap_obj *map); 677 678/** 679 * ttm_bo_kunmap 680 * 681 * @map: Object describing the map to unmap. 682 * 683 * Unmaps a kernel map set up by ttm_bo_kmap. 684 */ 685void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); 686 687/** 688 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object. 689 * 690 * @vma: vma as input from the fbdev mmap method. 691 * @bo: The bo backing the address space. The address space will 692 * have the same size as the bo, and start at offset 0. 693 * 694 * This function is intended to be called by the fbdev mmap method 695 * if the fbdev address space is to be backed by a bo. 696 */ 697int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo); 698 699/** 700 * ttm_bo_mmap - mmap out of the ttm device address space. 701 * 702 * @filp: filp as input from the mmap method. 703 * @vma: vma as input from the mmap method. 704 * @bdev: Pointer to the ttm_bo_device with the address space manager. 705 * 706 * This function is intended to be called by the device mmap method. 707 * if the device address space is to be backed by the bo manager. 708 */ 709int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, 710 struct ttm_bo_device *bdev); 711 712void *ttm_kmap_atomic_prot(struct page *page, pgprot_t prot); 713 714void ttm_kunmap_atomic_prot(void *addr, pgprot_t prot); 715 716/** 717 * ttm_bo_io 718 * 719 * @bdev: Pointer to the struct ttm_bo_device. 720 * @filp: Pointer to the struct file attempting to read / write. 721 * @wbuf: User-space pointer to address of buffer to write. NULL on read. 722 * @rbuf: User-space pointer to address of buffer to read into. 723 * Null on write. 724 * @count: Number of bytes to read / write. 725 * @f_pos: Pointer to current file position. 726 * @write: 1 for read, 0 for write. 727 * 728 * This function implements read / write into ttm buffer objects, and is 729 * intended to 730 * be called from the fops::read and fops::write method. 731 * Returns: 732 * See man (2) write, man(2) read. In particular, 733 * the function may return -ERESTARTSYS if 734 * interrupted by a signal. 735 */ 736ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp, 737 const char __user *wbuf, char __user *rbuf, 738 size_t count, loff_t *f_pos, bool write); 739 740int ttm_bo_swapout(struct ttm_bo_global *glob, 741 struct ttm_operation_ctx *ctx); 742void ttm_bo_swapout_all(struct ttm_bo_device *bdev); 743int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo); 744#endif 745