linux/include/drm/ttm/ttm_bo_api.h
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   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_gem.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/dma-resv.h>
  44
  45struct ttm_bo_global;
  46
  47struct ttm_bo_device;
  48
  49struct drm_mm_node;
  50
  51struct ttm_placement;
  52
  53struct ttm_place;
  54
  55struct ttm_lru_bulk_move;
  56
  57/**
  58 * struct ttm_bus_placement
  59 *
  60 * @addr:               mapped virtual address
  61 * @base:               bus base address
  62 * @is_iomem:           is this io memory ?
  63 * @size:               size in byte
  64 * @offset:             offset from the base address
  65 * @io_reserved_vm:     The VM system has a refcount in @io_reserved_count
  66 * @io_reserved_count:  Refcounting the numbers of callers to ttm_mem_io_reserve
  67 *
  68 * Structure indicating the bus placement of an object.
  69 */
  70struct ttm_bus_placement {
  71        void            *addr;
  72        phys_addr_t     base;
  73        unsigned long   size;
  74        unsigned long   offset;
  75        bool            is_iomem;
  76        bool            io_reserved_vm;
  77        uint64_t        io_reserved_count;
  78};
  79
  80
  81/**
  82 * struct ttm_mem_reg
  83 *
  84 * @mm_node: Memory manager node.
  85 * @size: Requested size of memory region.
  86 * @num_pages: Actual size of memory region in pages.
  87 * @page_alignment: Page alignment.
  88 * @placement: Placement flags.
  89 * @bus: Placement on io bus accessible to the CPU
  90 *
  91 * Structure indicating the placement and space resources used by a
  92 * buffer object.
  93 */
  94
  95struct ttm_mem_reg {
  96        void *mm_node;
  97        unsigned long start;
  98        unsigned long size;
  99        unsigned long num_pages;
 100        uint32_t page_alignment;
 101        uint32_t mem_type;
 102        uint32_t placement;
 103        struct ttm_bus_placement bus;
 104};
 105
 106/**
 107 * enum ttm_bo_type
 108 *
 109 * @ttm_bo_type_device: These are 'normal' buffers that can
 110 * be mmapped by user space. Each of these bos occupy a slot in the
 111 * device address space, that can be used for normal vm operations.
 112 *
 113 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
 114 * but they cannot be accessed from user-space. For kernel-only use.
 115 *
 116 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
 117 * driver.
 118 */
 119
 120enum ttm_bo_type {
 121        ttm_bo_type_device,
 122        ttm_bo_type_kernel,
 123        ttm_bo_type_sg
 124};
 125
 126struct ttm_tt;
 127
 128/**
 129 * struct ttm_buffer_object
 130 *
 131 * @base: drm_gem_object superclass data.
 132 * @bdev: Pointer to the buffer object device structure.
 133 * @type: The bo type.
 134 * @destroy: Destruction function. If NULL, kfree is used.
 135 * @num_pages: Actual number of pages.
 136 * @acc_size: Accounted size for this object.
 137 * @kref: Reference count of this buffer object. When this refcount reaches
 138 * zero, the object is destroyed or put on the delayed delete list.
 139 * @mem: structure describing current placement.
 140 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
 141 * pinned in physical memory. If this behaviour is not desired, this member
 142 * holds a pointer to a persistent shmem object.
 143 * @ttm: TTM structure holding system pages.
 144 * @evicted: Whether the object was evicted without user-space knowing.
 145 * @deleted: True if the object is only a zombie and already deleted.
 146 * @lru: List head for the lru list.
 147 * @ddestroy: List head for the delayed destroy list.
 148 * @swap: List head for swap LRU list.
 149 * @moving: Fence set when BO is moving
 150 * @offset: The current GPU offset, which can have different meanings
 151 * depending on the memory type. For SYSTEM type memory, it should be 0.
 152 * @cur_placement: Hint of current placement.
 153 *
 154 * Base class for TTM buffer object, that deals with data placement and CPU
 155 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
 156 * the driver can usually use the placement offset @offset directly as the
 157 * GPU virtual address. For drivers implementing multiple
 158 * GPU memory manager contexts, the driver should manage the address space
 159 * in these contexts separately and use these objects to get the correct
 160 * placement and caching for these GPU maps. This makes it possible to use
 161 * these objects for even quite elaborate memory management schemes.
 162 * The destroy member, the API visibility of this object makes it possible
 163 * to derive driver specific types.
 164 */
 165
 166struct ttm_buffer_object {
 167        struct drm_gem_object base;
 168
 169        /**
 170         * Members constant at init.
 171         */
 172
 173        struct ttm_bo_device *bdev;
 174        enum ttm_bo_type type;
 175        void (*destroy) (struct ttm_buffer_object *);
 176        unsigned long num_pages;
 177        size_t acc_size;
 178
 179        /**
 180        * Members not needing protection.
 181        */
 182        struct kref kref;
 183
 184        /**
 185         * Members protected by the bo::resv::reserved lock.
 186         */
 187
 188        struct ttm_mem_reg mem;
 189        struct file *persistent_swap_storage;
 190        struct ttm_tt *ttm;
 191        bool evicted;
 192        bool deleted;
 193
 194        /**
 195         * Members protected by the bdev::lru_lock.
 196         */
 197
 198        struct list_head lru;
 199        struct list_head ddestroy;
 200        struct list_head swap;
 201        struct list_head io_reserve_lru;
 202
 203        /**
 204         * Members protected by a bo reservation.
 205         */
 206
 207        struct dma_fence *moving;
 208        unsigned priority;
 209
 210        /**
 211         * Special members that are protected by the reserve lock
 212         * and the bo::lock when written to. Can be read with
 213         * either of these locks held.
 214         */
 215
 216        uint64_t offset; /* GPU address space is independent of CPU word size */
 217
 218        struct sg_table *sg;
 219};
 220
 221/**
 222 * struct ttm_bo_kmap_obj
 223 *
 224 * @virtual: The current kernel virtual address.
 225 * @page: The page when kmap'ing a single page.
 226 * @bo_kmap_type: Type of bo_kmap.
 227 *
 228 * Object describing a kernel mapping. Since a TTM bo may be located
 229 * in various memory types with various caching policies, the
 230 * mapping can either be an ioremap, a vmap, a kmap or part of a
 231 * premapped region.
 232 */
 233
 234#define TTM_BO_MAP_IOMEM_MASK 0x80
 235struct ttm_bo_kmap_obj {
 236        void *virtual;
 237        struct page *page;
 238        enum {
 239                ttm_bo_map_iomap        = 1 | TTM_BO_MAP_IOMEM_MASK,
 240                ttm_bo_map_vmap         = 2,
 241                ttm_bo_map_kmap         = 3,
 242                ttm_bo_map_premapped    = 4 | TTM_BO_MAP_IOMEM_MASK,
 243        } bo_kmap_type;
 244        struct ttm_buffer_object *bo;
 245};
 246
 247/**
 248 * struct ttm_operation_ctx
 249 *
 250 * @interruptible: Sleep interruptible if sleeping.
 251 * @no_wait_gpu: Return immediately if the GPU is busy.
 252 * @resv: Reservation object to allow reserved evictions with.
 253 * @flags: Including the following flags
 254 *
 255 * Context for TTM operations like changing buffer placement or general memory
 256 * allocation.
 257 */
 258struct ttm_operation_ctx {
 259        bool interruptible;
 260        bool no_wait_gpu;
 261        struct dma_resv *resv;
 262        uint64_t bytes_moved;
 263        uint32_t flags;
 264};
 265
 266/* Allow eviction of reserved BOs */
 267#define TTM_OPT_FLAG_ALLOW_RES_EVICT            0x1
 268/* when serving page fault or suspend, allow alloc anyway */
 269#define TTM_OPT_FLAG_FORCE_ALLOC                0x2
 270
 271/**
 272 * ttm_bo_get - reference a struct ttm_buffer_object
 273 *
 274 * @bo: The buffer object.
 275 */
 276static inline void ttm_bo_get(struct ttm_buffer_object *bo)
 277{
 278        kref_get(&bo->kref);
 279}
 280
 281/**
 282 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
 283 * its refcount has already reached zero.
 284 * @bo: The buffer object.
 285 *
 286 * Used to reference a TTM buffer object in lookups where the object is removed
 287 * from the lookup structure during the destructor and for RCU lookups.
 288 *
 289 * Returns: @bo if the referencing was successful, NULL otherwise.
 290 */
 291static inline __must_check struct ttm_buffer_object *
 292ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
 293{
 294        if (!kref_get_unless_zero(&bo->kref))
 295                return NULL;
 296        return bo;
 297}
 298
 299/**
 300 * ttm_bo_wait - wait for buffer idle.
 301 *
 302 * @bo:  The buffer object.
 303 * @interruptible:  Use interruptible wait.
 304 * @no_wait:  Return immediately if buffer is busy.
 305 *
 306 * This function must be called with the bo::mutex held, and makes
 307 * sure any previous rendering to the buffer is completed.
 308 * Note: It might be necessary to block validations before the
 309 * wait by reserving the buffer.
 310 * Returns -EBUSY if no_wait is true and the buffer is busy.
 311 * Returns -ERESTARTSYS if interrupted by a signal.
 312 */
 313int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
 314
 315/**
 316 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
 317 *
 318 * @placement:  Return immediately if buffer is busy.
 319 * @mem:  The struct ttm_mem_reg indicating the region where the bo resides
 320 * @new_flags: Describes compatible placement found
 321 *
 322 * Returns true if the placement is compatible
 323 */
 324bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_mem_reg *mem,
 325                       uint32_t *new_flags);
 326
 327/**
 328 * ttm_bo_validate
 329 *
 330 * @bo: The buffer object.
 331 * @placement: Proposed placement for the buffer object.
 332 * @ctx: validation parameters.
 333 *
 334 * Changes placement and caching policy of the buffer object
 335 * according proposed placement.
 336 * Returns
 337 * -EINVAL on invalid proposed placement.
 338 * -ENOMEM on out-of-memory condition.
 339 * -EBUSY if no_wait is true and buffer busy.
 340 * -ERESTARTSYS if interrupted by a signal.
 341 */
 342int ttm_bo_validate(struct ttm_buffer_object *bo,
 343                    struct ttm_placement *placement,
 344                    struct ttm_operation_ctx *ctx);
 345
 346/**
 347 * ttm_bo_put
 348 *
 349 * @bo: The buffer object.
 350 *
 351 * Unreference a buffer object.
 352 */
 353void ttm_bo_put(struct ttm_buffer_object *bo);
 354
 355/**
 356 * ttm_bo_move_to_lru_tail
 357 *
 358 * @bo: The buffer object.
 359 * @bulk: optional bulk move structure to remember BO positions
 360 *
 361 * Move this BO to the tail of all lru lists used to lookup and reserve an
 362 * object. This function must be called with struct ttm_bo_global::lru_lock
 363 * held, and is used to make a BO less likely to be considered for eviction.
 364 */
 365void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
 366                             struct ttm_lru_bulk_move *bulk);
 367
 368/**
 369 * ttm_bo_bulk_move_lru_tail
 370 *
 371 * @bulk: bulk move structure
 372 *
 373 * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
 374 * BO order never changes. Should be called with ttm_bo_global::lru_lock held.
 375 */
 376void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
 377
 378/**
 379 * ttm_bo_lock_delayed_workqueue
 380 *
 381 * Prevent the delayed workqueue from running.
 382 * Returns
 383 * True if the workqueue was queued at the time
 384 */
 385int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
 386
 387/**
 388 * ttm_bo_unlock_delayed_workqueue
 389 *
 390 * Allows the delayed workqueue to run.
 391 */
 392void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched);
 393
 394/**
 395 * ttm_bo_eviction_valuable
 396 *
 397 * @bo: The buffer object to evict
 398 * @place: the placement we need to make room for
 399 *
 400 * Check if it is valuable to evict the BO to make room for the given placement.
 401 */
 402bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
 403                              const struct ttm_place *place);
 404
 405/**
 406 * ttm_bo_acc_size
 407 *
 408 * @bdev: Pointer to a ttm_bo_device struct.
 409 * @bo_size: size of the buffer object in byte.
 410 * @struct_size: size of the structure holding buffer object datas
 411 *
 412 * Returns size to account for a buffer object
 413 */
 414size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
 415                       unsigned long bo_size,
 416                       unsigned struct_size);
 417size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
 418                           unsigned long bo_size,
 419                           unsigned struct_size);
 420
 421/**
 422 * ttm_bo_init_reserved
 423 *
 424 * @bdev: Pointer to a ttm_bo_device struct.
 425 * @bo: Pointer to a ttm_buffer_object to be initialized.
 426 * @size: Requested size of buffer object.
 427 * @type: Requested type of buffer object.
 428 * @flags: Initial placement flags.
 429 * @page_alignment: Data alignment in pages.
 430 * @ctx: TTM operation context for memory allocation.
 431 * @acc_size: Accounted size for this object.
 432 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
 433 * @destroy: Destroy function. Use NULL for kfree().
 434 *
 435 * This function initializes a pre-allocated struct ttm_buffer_object.
 436 * As this object may be part of a larger structure, this function,
 437 * together with the @destroy function,
 438 * enables driver-specific objects derived from a ttm_buffer_object.
 439 *
 440 * On successful return, the caller owns an object kref to @bo. The kref and
 441 * list_kref are usually set to 1, but note that in some situations, other
 442 * tasks may already be holding references to @bo as well.
 443 * Furthermore, if resv == NULL, the buffer's reservation lock will be held,
 444 * and it is the caller's responsibility to call ttm_bo_unreserve.
 445 *
 446 * If a failure occurs, the function will call the @destroy function, or
 447 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
 448 * illegal and will likely cause memory corruption.
 449 *
 450 * Returns
 451 * -ENOMEM: Out of memory.
 452 * -EINVAL: Invalid placement flags.
 453 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
 454 */
 455
 456int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
 457                         struct ttm_buffer_object *bo,
 458                         unsigned long size,
 459                         enum ttm_bo_type type,
 460                         struct ttm_placement *placement,
 461                         uint32_t page_alignment,
 462                         struct ttm_operation_ctx *ctx,
 463                         size_t acc_size,
 464                         struct sg_table *sg,
 465                         struct dma_resv *resv,
 466                         void (*destroy) (struct ttm_buffer_object *));
 467
 468/**
 469 * ttm_bo_init
 470 *
 471 * @bdev: Pointer to a ttm_bo_device struct.
 472 * @bo: Pointer to a ttm_buffer_object to be initialized.
 473 * @size: Requested size of buffer object.
 474 * @type: Requested type of buffer object.
 475 * @flags: Initial placement flags.
 476 * @page_alignment: Data alignment in pages.
 477 * @interruptible: If needing to sleep to wait for GPU resources,
 478 * sleep interruptible.
 479 * pinned in physical memory. If this behaviour is not desired, this member
 480 * holds a pointer to a persistent shmem object. Typically, this would
 481 * point to the shmem object backing a GEM object if TTM is used to back a
 482 * GEM user interface.
 483 * @acc_size: Accounted size for this object.
 484 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
 485 * @destroy: Destroy function. Use NULL for kfree().
 486 *
 487 * This function initializes a pre-allocated struct ttm_buffer_object.
 488 * As this object may be part of a larger structure, this function,
 489 * together with the @destroy function,
 490 * enables driver-specific objects derived from a ttm_buffer_object.
 491 *
 492 * On successful return, the caller owns an object kref to @bo. The kref and
 493 * list_kref are usually set to 1, but note that in some situations, other
 494 * tasks may already be holding references to @bo as well.
 495 *
 496 * If a failure occurs, the function will call the @destroy function, or
 497 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
 498 * illegal and will likely cause memory corruption.
 499 *
 500 * Returns
 501 * -ENOMEM: Out of memory.
 502 * -EINVAL: Invalid placement flags.
 503 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
 504 */
 505int ttm_bo_init(struct ttm_bo_device *bdev, struct ttm_buffer_object *bo,
 506                unsigned long size, enum ttm_bo_type type,
 507                struct ttm_placement *placement,
 508                uint32_t page_alignment, bool interrubtible, size_t acc_size,
 509                struct sg_table *sg, struct dma_resv *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 * @p_bo: On successful completion *p_bo points to the created object.
 523 *
 524 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
 525 * on that object. The destroy function is set to kfree().
 526 * Returns
 527 * -ENOMEM: Out of memory.
 528 * -EINVAL: Invalid placement flags.
 529 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
 530 */
 531int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size,
 532                  enum ttm_bo_type type, struct ttm_placement *placement,
 533                  uint32_t page_alignment, bool interruptible,
 534                  struct ttm_buffer_object **p_bo);
 535
 536/**
 537 * ttm_bo_init_mm
 538 *
 539 * @bdev: Pointer to a ttm_bo_device struct.
 540 * @mem_type: The memory type.
 541 * @p_size: size managed area in pages.
 542 *
 543 * Initialize a manager for a given memory type.
 544 * Note: if part of driver firstopen, it must be protected from a
 545 * potentially racing lastclose.
 546 * Returns:
 547 * -EINVAL: invalid size or memory type.
 548 * -ENOMEM: Not enough memory.
 549 * May also return driver-specified errors.
 550 */
 551int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
 552                   unsigned long p_size);
 553
 554/**
 555 * ttm_bo_clean_mm
 556 *
 557 * @bdev: Pointer to a ttm_bo_device struct.
 558 * @mem_type: The memory type.
 559 *
 560 * Take down a manager for a given memory type after first walking
 561 * the LRU list to evict any buffers left alive.
 562 *
 563 * Normally, this function is part of lastclose() or unload(), and at that
 564 * point there shouldn't be any buffers left created by user-space, since
 565 * there should've been removed by the file descriptor release() method.
 566 * However, before this function is run, make sure to signal all sync objects,
 567 * and verify that the delayed delete queue is empty. The driver must also
 568 * make sure that there are no NO_EVICT buffers present in this memory type
 569 * when the call is made.
 570 *
 571 * If this function is part of a VT switch, the caller must make sure that
 572 * there are no appications currently validating buffers before this
 573 * function is called. The caller can do that by first taking the
 574 * struct ttm_bo_device::ttm_lock in write mode.
 575 *
 576 * Returns:
 577 * -EINVAL: invalid or uninitialized memory type.
 578 * -EBUSY: There are still buffers left in this memory type.
 579 */
 580int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
 581
 582/**
 583 * ttm_bo_evict_mm
 584 *
 585 * @bdev: Pointer to a ttm_bo_device struct.
 586 * @mem_type: The memory type.
 587 *
 588 * Evicts all buffers on the lru list of the memory type.
 589 * This is normally part of a VT switch or an
 590 * out-of-memory-space-due-to-fragmentation handler.
 591 * The caller must make sure that there are no other processes
 592 * currently validating buffers, and can do that by taking the
 593 * struct ttm_bo_device::ttm_lock in write mode.
 594 *
 595 * Returns:
 596 * -EINVAL: Invalid or uninitialized memory type.
 597 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
 598 * evict a buffer.
 599 */
 600int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
 601
 602/**
 603 * ttm_kmap_obj_virtual
 604 *
 605 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
 606 * @is_iomem: Pointer to an integer that on return indicates 1 if the
 607 * virtual map is io memory, 0 if normal memory.
 608 *
 609 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
 610 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
 611 * that should strictly be accessed by the iowriteXX() and similar functions.
 612 */
 613static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
 614                                         bool *is_iomem)
 615{
 616        *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
 617        return map->virtual;
 618}
 619
 620/**
 621 * ttm_bo_kmap
 622 *
 623 * @bo: The buffer object.
 624 * @start_page: The first page to map.
 625 * @num_pages: Number of pages to map.
 626 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
 627 *
 628 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
 629 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
 630 * used to obtain a virtual address to the data.
 631 *
 632 * Returns
 633 * -ENOMEM: Out of memory.
 634 * -EINVAL: Invalid range.
 635 */
 636int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
 637                unsigned long num_pages, struct ttm_bo_kmap_obj *map);
 638
 639/**
 640 * ttm_bo_kunmap
 641 *
 642 * @map: Object describing the map to unmap.
 643 *
 644 * Unmaps a kernel map set up by ttm_bo_kmap.
 645 */
 646void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
 647
 648/**
 649 * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
 650 *
 651 * @vma:       vma as input from the fbdev mmap method.
 652 * @bo:        The bo backing the address space.
 653 *
 654 * Maps a buffer object.
 655 */
 656int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
 657
 658/**
 659 * ttm_bo_mmap - mmap out of the ttm device address space.
 660 *
 661 * @filp:      filp as input from the mmap method.
 662 * @vma:       vma as input from the mmap method.
 663 * @bdev:      Pointer to the ttm_bo_device with the address space manager.
 664 *
 665 * This function is intended to be called by the device mmap method.
 666 * if the device address space is to be backed by the bo manager.
 667 */
 668int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
 669                struct ttm_bo_device *bdev);
 670
 671/**
 672 * ttm_bo_io
 673 *
 674 * @bdev:      Pointer to the struct ttm_bo_device.
 675 * @filp:      Pointer to the struct file attempting to read / write.
 676 * @wbuf:      User-space pointer to address of buffer to write. NULL on read.
 677 * @rbuf:      User-space pointer to address of buffer to read into.
 678 * Null on write.
 679 * @count:     Number of bytes to read / write.
 680 * @f_pos:     Pointer to current file position.
 681 * @write:     1 for read, 0 for write.
 682 *
 683 * This function implements read / write into ttm buffer objects, and is
 684 * intended to
 685 * be called from the fops::read and fops::write method.
 686 * Returns:
 687 * See man (2) write, man(2) read. In particular,
 688 * the function may return -ERESTARTSYS if
 689 * interrupted by a signal.
 690 */
 691ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
 692                  const char __user *wbuf, char __user *rbuf,
 693                  size_t count, loff_t *f_pos, bool write);
 694
 695int ttm_bo_swapout(struct ttm_bo_global *glob,
 696                        struct ttm_operation_ctx *ctx);
 697void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
 698
 699/**
 700 * ttm_bo_uses_embedded_gem_object - check if the given bo uses the
 701 * embedded drm_gem_object.
 702 *
 703 * Most ttm drivers are using gem too, so the embedded
 704 * ttm_buffer_object.base will be initialized by the driver (before
 705 * calling ttm_bo_init).  It is also possible to use ttm without gem
 706 * though (vmwgfx does that).
 707 *
 708 * This helper will figure whenever a given ttm bo is a gem object too
 709 * or not.
 710 *
 711 * @bo: The bo to check.
 712 */
 713static inline bool ttm_bo_uses_embedded_gem_object(struct ttm_buffer_object *bo)
 714{
 715        return bo->base.dev != NULL;
 716}
 717
 718/* Default number of pre-faulted pages in the TTM fault handler */
 719#define TTM_BO_VM_NUM_PREFAULT 16
 720
 721vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
 722                             struct vm_fault *vmf);
 723
 724vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 725                                    pgprot_t prot,
 726                                    pgoff_t num_prefault,
 727                                    pgoff_t fault_page_size);
 728
 729vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
 730
 731void ttm_bo_vm_open(struct vm_area_struct *vma);
 732
 733void ttm_bo_vm_close(struct vm_area_struct *vma);
 734
 735int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
 736                     void *buf, int len, int write);
 737
 738#endif
 739