include/drm/ttm/ttm_bo_api.h

   1 /**************************************************************************
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   3  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
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  11  * permit persons to whom the Software is furnished to do so, subject to
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  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.
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  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
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  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
  44 struct ttm_bo_device;
  45
  46 struct drm_mm_node;
  47
  48 /**
  49  * struct ttm_place
  50  *
  51  * @fpfn:       first valid page frame number to put the object
  52  * @lpfn:       last valid page frame number to put the object
  53  * @flags:      memory domain and caching flags for the object
  54  *
  55  * Structure indicating a possible place to put an object.
  56  */
  57 struct ttm_place {
  58         unsigned        fpfn;
  59         unsigned        lpfn;
  60         uint32_t        flags;
  61 };
  62
  63 /**
  64  * struct ttm_placement
  65  *
  66  * @num_placement:      number of preferred placements
  67  * @placement:          preferred placements
  68  * @num_busy_placement: number of preferred placements when need to evict buffer
  69  * @busy_placement:     preferred placements when need to evict buffer
  70  *
  71  * Structure indicating the placement you request for an object.
  72  */
  73 struct ttm_placement {
  74         unsigned                num_placement;
  75         const struct ttm_place  *placement;
  76         unsigned                num_busy_placement;
  77         const struct ttm_place  *busy_placement;
  78 };
  79
  80 /**
  81  * struct ttm_bus_placement
  82  *
  83  * @addr:               mapped virtual address
  84  * @base:               bus base address
  85  * @is_iomem:           is this io memory ?
  86  * @size:               size in byte
  87  * @offset:             offset from the base address
  88  * @io_reserved_vm:     The VM system has a refcount in @io_reserved_count
  89  * @io_reserved_count:  Refcounting the numbers of callers to ttm_mem_io_reserve
  90  *
  91  * Structure indicating the bus placement of an object.
  92  */
  93 struct ttm_bus_placement {
  94         void            *addr;
  95         phys_addr_t     base;
  96         unsigned long   size;
  97         unsigned long   offset;
  98         bool            is_iomem;
  99         bool            io_reserved_vm;
 100         uint64_t        io_reserved_count;
 101 };
 102
 103
 104 /**
 105  * struct ttm_mem_reg
 106  *
 107  * @mm_node: Memory manager node.
 108  * @size: Requested size of memory region.
 109  * @num_pages: Actual size of memory region in pages.
 110  * @page_alignment: Page alignment.
 111  * @placement: Placement flags.
 112  * @bus: Placement on io bus accessible to the CPU
 113  *
 114  * Structure indicating the placement and space resources used by a
 115  * buffer object.
 116  */
 117
 118 struct ttm_mem_reg {
 119         void *mm_node;
 120         unsigned long start;
 121         unsigned long size;
 122         unsigned long num_pages;
 123         uint32_t page_alignment;
 124         uint32_t mem_type;
 125         uint32_t placement;
 126         struct ttm_bus_placement bus;
 127 };
 128
 129 /**
 130  * enum ttm_bo_type
 131  *
 132  * @ttm_bo_type_device: These are 'normal' buffers that can
 133  * be mmapped by user space. Each of these bos occupy a slot in the
 134  * device address space, that can be used for normal vm operations.
 135  *
 136  * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
 137  * but they cannot be accessed from user-space. For kernel-only use.
 138  *
 139  * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
 140  * driver.
 141  */
 142
 143 enum ttm_bo_type {
 144         ttm_bo_type_device,
 145         ttm_bo_type_kernel,
 146         ttm_bo_type_sg
 147 };
 148
 149 struct ttm_tt;
 150
 151 /**
 152  * struct ttm_buffer_object
 153  *
 154  * @bdev: Pointer to the buffer object device structure.
 155  * @type: The bo type.
 156  * @destroy: Destruction function. If NULL, kfree is used.
 157  * @num_pages: Actual number of pages.
 158  * @acc_size: Accounted size for this object.
 159  * @kref: Reference count of this buffer object. When this refcount reaches
 160  * zero, the object is put on the delayed delete list.
 161  * @list_kref: List reference count of this buffer object. This member is
 162  * used to avoid destruction while the buffer object is still on a list.
 163  * Lru lists may keep one refcount, the delayed delete list, and kref != 0
 164  * keeps one refcount. When this refcount reaches zero,
 165  * the object is destroyed.
 166  * @mem: structure describing current placement.
 167  * @persistent_swap_storage: Usually the swap storage is deleted for buffers
 168  * pinned in physical memory. If this behaviour is not desired, this member
 169  * holds a pointer to a persistent shmem object.
 170  * @ttm: TTM structure holding system pages.
 171  * @evicted: Whether the object was evicted without user-space knowing.
 172  * @cpu_writes: For synchronization. Number of cpu writers.
 173  * @lru: List head for the lru list.
 174  * @ddestroy: List head for the delayed destroy list.
 175  * @swap: List head for swap LRU list.
 176  * @moving: Fence set when BO is moving
 177  * @vma_node: Address space manager node.
 178  * @offset: The current GPU offset, which can have different meanings
 179  * depending on the memory type. For SYSTEM type memory, it should be 0.
 180  * @cur_placement: Hint of current placement.
 181  * @wu_mutex: Wait unreserved mutex.
 182  *
 183  * Base class for TTM buffer object, that deals with data placement and CPU
 184  * mappings. GPU mappings are really up to the driver, but for simpler GPUs
 185  * the driver can usually use the placement offset @offset directly as the
 186  * GPU virtual address. For drivers implementing multiple
 187  * GPU memory manager contexts, the driver should manage the address space
 188  * in these contexts separately and use these objects to get the correct
 189  * placement and caching for these GPU maps. This makes it possible to use
 190  * these objects for even quite elaborate memory management schemes.
 191  * The destroy member, the API visibility of this object makes it possible
 192  * to derive driver specific types.
 193  */
 194
 195 struct ttm_buffer_object {
 196         /**
 197          * Members constant at init.
 198          */
 199
 200         struct ttm_bo_global *glob;
 201         struct ttm_bo_device *bdev;
 202         enum ttm_bo_type type;
 203         void (*destroy) (struct ttm_buffer_object *);
 204         unsigned long num_pages;
 205         size_t acc_size;
 206
 207         /**
 208         * Members not needing protection.
 209         */
 210
 211         struct kref kref;
 212         struct kref list_kref;
 213
 214         /**
 215          * Members protected by the bo::resv::reserved lock.
 216          */
 217
 218         struct ttm_mem_reg mem;
 219         struct file *persistent_swap_storage;
 220         struct ttm_tt *ttm;
 221         bool evicted;
 222
 223         /**
 224          * Members protected by the bo::reserved lock only when written to.
 225          */
 226
 227         atomic_t cpu_writers;
 228
 229         /**
 230          * Members protected by the bdev::lru_lock.
 231          */
 232
 233         struct list_head lru;
 234         struct list_head ddestroy;
 235         struct list_head swap;
 236         struct list_head io_reserve_lru;
 237
 238         /**
 239          * Members protected by a bo reservation.
 240          */
 241
 242         struct fence *moving;
 243
 244         struct drm_vma_offset_node vma_node;
 245
 246         /**
 247          * Special members that are protected by the reserve lock
 248          * and the bo::lock when written to. Can be read with
 249          * either of these locks held.
 250          */
 251
 252         uint64_t offset; /* GPU address space is independent of CPU word size */
 253         uint32_t cur_placement;
 254
 255         struct sg_table *sg;
 256
 257         struct reservation_object *resv;
 258         struct reservation_object ttm_resv;
 259         struct mutex wu_mutex;
 260 };
 261
 262 /**
 263  * struct ttm_bo_kmap_obj
 264  *
 265  * @virtual: The current kernel virtual address.
 266  * @page: The page when kmap'ing a single page.
 267  * @bo_kmap_type: Type of bo_kmap.
 268  *
 269  * Object describing a kernel mapping. Since a TTM bo may be located
 270  * in various memory types with various caching policies, the
 271  * mapping can either be an ioremap, a vmap, a kmap or part of a
 272  * premapped region.
 273  */
 274
 275 #define TTM_BO_MAP_IOMEM_MASK 0x80
 276 struct ttm_bo_kmap_obj {
 277         void *virtual;
 278         struct page *page;
 279         enum {
 280                 ttm_bo_map_iomap        = 1 | TTM_BO_MAP_IOMEM_MASK,
 281                 ttm_bo_map_vmap         = 2,
 282                 ttm_bo_map_kmap         = 3,
 283                 ttm_bo_map_premapped    = 4 | TTM_BO_MAP_IOMEM_MASK,
 284         } bo_kmap_type;
 285         struct ttm_buffer_object *bo;
 286 };
 287
 288 /**
 289  * ttm_bo_reference - reference a struct ttm_buffer_object
 290  *
 291  * @bo: The buffer object.
 292  *
 293  * Returns a refcounted pointer to a buffer object.
 294  */
 295
 296 static inline struct ttm_buffer_object *
 297 ttm_bo_reference(struct ttm_buffer_object *bo)
 298 {
 299         kref_get(&bo->kref);
 300         return bo;
 301 }
 302
 303 /**
 304  * ttm_bo_wait - wait for buffer idle.
 305  *
 306  * @bo:  The buffer object.
 307  * @interruptible:  Use interruptible wait.
 308  * @no_wait:  Return immediately if buffer is busy.
 309  *
 310  * This function must be called with the bo::mutex held, and makes
 311  * sure any previous rendering to the buffer is completed.
 312  * Note: It might be necessary to block validations before the
 313  * wait by reserving the buffer.
 314  * Returns -EBUSY if no_wait is true and the buffer is busy.
 315  * Returns -ERESTARTSYS if interrupted by a signal.
 316  */
 317 extern int ttm_bo_wait(struct ttm_buffer_object *bo,
 318                        bool interruptible, bool no_wait);
 319
 320 /**
 321  * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
 322  *
 323  * @placement:  Return immediately if buffer is busy.
 324  * @mem:  The struct ttm_mem_reg indicating the region where the bo resides
 325  * @new_flags: Describes compatible placement found
 326  *
 327  * Returns true if the placement is compatible
 328  */
 329 extern bool ttm_bo_mem_compat(struct ttm_placement *placement,
 330                               struct ttm_mem_reg *mem,
 331                               uint32_t *new_flags);
 332
 333 /**
 334  * ttm_bo_validate
 335  *
 336  * @bo: The buffer object.
 337  * @placement: Proposed placement for the buffer object.
 338  * @interruptible: Sleep interruptible if sleeping.
 339  * @no_wait_gpu: Return immediately if the GPU is busy.
 340  *
 341  * Changes placement and caching policy of the buffer object
 342  * according proposed placement.
 343  * Returns
 344  * -EINVAL on invalid proposed placement.
 345  * -ENOMEM on out-of-memory condition.
 346  * -EBUSY if no_wait is true and buffer busy.
 347  * -ERESTARTSYS if interrupted by a signal.
 348  */
 349 extern int ttm_bo_validate(struct ttm_buffer_object *bo,
 350                                 struct ttm_placement *placement,
 351                                 bool interruptible,
 352                                 bool no_wait_gpu);
 353
 354 /**
 355  * ttm_bo_unref
 356  *
 357  * @bo: The buffer object.
 358  *
 359  * Unreference and clear a pointer to a buffer object.
 360  */
 361 extern void ttm_bo_unref(struct ttm_buffer_object **bo);
 362
 363
 364 /**
 365  * ttm_bo_list_ref_sub
 366  *
 367  * @bo: The buffer object.
 368  * @count: The number of references with which to decrease @bo::list_kref;
 369  * @never_free: The refcount should not reach zero with this operation.
 370  *
 371  * Release @count lru list references to this buffer object.
 372  */
 373 extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count,
 374                                 bool never_free);
 375
 376 /**
 377  * ttm_bo_add_to_lru
 378  *
 379  * @bo: The buffer object.
 380  *
 381  * Add this bo to the relevant mem type lru and, if it's backed by
 382  * system pages (ttms) to the swap list.
 383  * This function must be called with struct ttm_bo_global::lru_lock held, and
 384  * is typically called immediately prior to unreserving a bo.
 385  */
 386 extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
 387
 388 /**
 389  * ttm_bo_del_from_lru
 390  *
 391  * @bo: The buffer object.
 392  *
 393  * Remove this bo from all lru lists used to lookup and reserve an object.
 394  * This function must be called with struct ttm_bo_global::lru_lock held,
 395  * and is usually called just immediately after the bo has been reserved to
 396  * avoid recursive reservation from lru lists.
 397  */
 398 extern int ttm_bo_del_from_lru(struct ttm_buffer_object *bo);
 399
 400 /**
 401  * ttm_bo_move_to_lru_tail
 402  *
 403  * @bo: The buffer object.
 404  *
 405  * Move this BO to the tail of all lru lists used to lookup and reserve an
 406  * object. This function must be called with struct ttm_bo_global::lru_lock
 407  * held, and is used to make a BO less likely to be considered for eviction.
 408  */
 409 extern void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
 410
 411 /**
 412  * ttm_bo_lock_delayed_workqueue
 413  *
 414  * Prevent the delayed workqueue from running.
 415  * Returns
 416  * True if the workqueue was queued at the time
 417  */
 418 extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
 419
 420 /**
 421  * ttm_bo_unlock_delayed_workqueue
 422  *
 423  * Allows the delayed workqueue to run.
 424  */
 425 extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev,
 426                                             int resched);
 427
 428 /**
 429  * ttm_bo_synccpu_write_grab
 430  *
 431  * @bo: The buffer object:
 432  * @no_wait: Return immediately if buffer is busy.
 433  *
 434  * Synchronizes a buffer object for CPU RW access. This means
 435  * command submission that affects the buffer will return -EBUSY
 436  * until ttm_bo_synccpu_write_release is called.
 437  *
 438  * Returns
 439  * -EBUSY if the buffer is busy and no_wait is true.
 440  * -ERESTARTSYS if interrupted by a signal.
 441  */
 442 extern int
 443 ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait);
 444
 445 /**
 446  * ttm_bo_synccpu_write_release:
 447  *
 448  * @bo : The buffer object.
 449  *
 450  * Releases a synccpu lock.
 451  */
 452 extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
 453
 454 /**
 455  * ttm_bo_acc_size
 456  *
 457  * @bdev: Pointer to a ttm_bo_device struct.
 458  * @bo_size: size of the buffer object in byte.
 459  * @struct_size: size of the structure holding buffer object datas
 460  *
 461  * Returns size to account for a buffer object
 462  */
 463 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
 464                        unsigned long bo_size,
 465                        unsigned struct_size);
 466 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
 467                            unsigned long bo_size,
 468                            unsigned struct_size);
 469
 470 /**
 471  * ttm_bo_init
 472  *
 473  * @bdev: Pointer to a ttm_bo_device struct.
 474  * @bo: Pointer to a ttm_buffer_object to be initialized.
 475  * @size: Requested size of buffer object.
 476  * @type: Requested type of buffer object.
 477  * @flags: Initial placement flags.
 478  * @page_alignment: Data alignment in pages.
 479  * @interruptible: If needing to sleep to wait for GPU resources,
 480  * sleep interruptible.
 481  * @persistent_swap_storage: Usually the swap storage is deleted for buffers
 482  * pinned in physical memory. If this behaviour is not desired, this member
 483  * holds a pointer to a persistent shmem object. Typically, this would
 484  * point to the shmem object backing a GEM object if TTM is used to back a
 485  * GEM user interface.
 486  * @acc_size: Accounted size for this object.
 487  * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one.
 488  * @destroy: Destroy function. Use NULL for kfree().
 489  *
 490  * This function initializes a pre-allocated struct ttm_buffer_object.
 491  * As this object may be part of a larger structure, this function,
 492  * together with the @destroy function,
 493  * enables driver-specific objects derived from a ttm_buffer_object.
 494  * On successful return, the object kref and list_kref are set to 1.
 495  * If a failure occurs, the function will call the @destroy function, or
 496  * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
 497  * illegal and will likely cause memory corruption.
 498  *
 499  * Returns
 500  * -ENOMEM: Out of memory.
 501  * -EINVAL: Invalid placement flags.
 502  * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
 503  */
 504
 505 extern int ttm_bo_init(struct ttm_bo_device *bdev,
 506                         struct ttm_buffer_object *bo,
 507                         unsigned long size,
 508                         enum ttm_bo_type type,
 509                         struct ttm_placement *placement,
 510                         uint32_t page_alignment,
 511                         bool interrubtible,
 512                         struct file *persistent_swap_storage,
 513                         size_t acc_size,
 514                         struct sg_table *sg,
 515                         struct reservation_object *resv,
 516                         void (*destroy) (struct ttm_buffer_object *));
 517
 518 /**
 519  * ttm_bo_create
 520  *
 521  * @bdev: Pointer to a ttm_bo_device struct.
 522  * @size: Requested size of buffer object.
 523  * @type: Requested type of buffer object.
 524  * @placement: Initial placement.
 525  * @page_alignment: Data alignment in pages.
 526  * @interruptible: If needing to sleep while waiting for GPU resources,
 527  * sleep interruptible.
 528  * @persistent_swap_storage: Usually the swap storage is deleted for buffers
 529  * pinned in physical memory. If this behaviour is not desired, this member
 530  * holds a pointer to a persistent shmem object. Typically, this would
 531  * point to the shmem object backing a GEM object if TTM is used to back a
 532  * GEM user interface.
 533  * @p_bo: On successful completion *p_bo points to the created object.
 534  *
 535  * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
 536  * on that object. The destroy function is set to kfree().
 537  * Returns
 538  * -ENOMEM: Out of memory.
 539  * -EINVAL: Invalid placement flags.
 540  * -ERESTARTSYS: Interrupted by signal while waiting for resources.
 541  */
 542
 543 extern int ttm_bo_create(struct ttm_bo_device *bdev,
 544                                 unsigned long size,
 545                                 enum ttm_bo_type type,
 546                                 struct ttm_placement *placement,
 547                                 uint32_t page_alignment,
 548                                 bool interruptible,
 549                                 struct file *persistent_swap_storage,
 550                                 struct ttm_buffer_object **p_bo);
 551
 552 /**
 553  * ttm_bo_init_mm
 554  *
 555  * @bdev: Pointer to a ttm_bo_device struct.
 556  * @mem_type: The memory type.
 557  * @p_size: size managed area in pages.
 558  *
 559  * Initialize a manager for a given memory type.
 560  * Note: if part of driver firstopen, it must be protected from a
 561  * potentially racing lastclose.
 562  * Returns:
 563  * -EINVAL: invalid size or memory type.
 564  * -ENOMEM: Not enough memory.
 565  * May also return driver-specified errors.
 566  */
 567
 568 extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
 569                                 unsigned long p_size);
 570 /**
 571  * ttm_bo_clean_mm
 572  *
 573  * @bdev: Pointer to a ttm_bo_device struct.
 574  * @mem_type: The memory type.
 575  *
 576  * Take down a manager for a given memory type after first walking
 577  * the LRU list to evict any buffers left alive.
 578  *
 579  * Normally, this function is part of lastclose() or unload(), and at that
 580  * point there shouldn't be any buffers left created by user-space, since
 581  * there should've been removed by the file descriptor release() method.
 582  * However, before this function is run, make sure to signal all sync objects,
 583  * and verify that the delayed delete queue is empty. The driver must also
 584  * make sure that there are no NO_EVICT buffers present in this memory type
 585  * when the call is made.
 586  *
 587  * If this function is part of a VT switch, the caller must make sure that
 588  * there are no appications currently validating buffers before this
 589  * function is called. The caller can do that by first taking the
 590  * struct ttm_bo_device::ttm_lock in write mode.
 591  *
 592  * Returns:
 593  * -EINVAL: invalid or uninitialized memory type.
 594  * -EBUSY: There are still buffers left in this memory type.
 595  */
 596
 597 extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
 598
 599 /**
 600  * ttm_bo_evict_mm
 601  *
 602  * @bdev: Pointer to a ttm_bo_device struct.
 603  * @mem_type: The memory type.
 604  *
 605  * Evicts all buffers on the lru list of the memory type.
 606  * This is normally part of a VT switch or an
 607  * out-of-memory-space-due-to-fragmentation handler.
 608  * The caller must make sure that there are no other processes
 609  * currently validating buffers, and can do that by taking the
 610  * struct ttm_bo_device::ttm_lock in write mode.
 611  *
 612  * Returns:
 613  * -EINVAL: Invalid or uninitialized memory type.
 614  * -ERESTARTSYS: The call was interrupted by a signal while waiting to
 615  * evict a buffer.
 616  */
 617
 618 extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
 619
 620 /**
 621  * ttm_kmap_obj_virtual
 622  *
 623  * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
 624  * @is_iomem: Pointer to an integer that on return indicates 1 if the
 625  * virtual map is io memory, 0 if normal memory.
 626  *
 627  * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
 628  * If *is_iomem is 1 on return, the virtual address points to an io memory area,
 629  * that should strictly be accessed by the iowriteXX() and similar functions.
 630  */
 631
 632 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
 633                                          bool *is_iomem)
 634 {
 635         *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
 636         return map->virtual;
 637 }
 638
 639 /**
 640  * ttm_bo_kmap
 641  *
 642  * @bo: The buffer object.
 643  * @start_page: The first page to map.
 644  * @num_pages: Number of pages to map.
 645  * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
 646  *
 647  * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
 648  * data in the buffer object. The ttm_kmap_obj_virtual function can then be
 649  * used to obtain a virtual address to the data.
 650  *
 651  * Returns
 652  * -ENOMEM: Out of memory.
 653  * -EINVAL: Invalid range.
 654  */
 655
 656 extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
 657                        unsigned long num_pages, struct ttm_bo_kmap_obj *map);
 658
 659 /**
 660  * ttm_bo_kunmap
 661  *
 662  * @map: Object describing the map to unmap.
 663  *
 664  * Unmaps a kernel map set up by ttm_bo_kmap.
 665  */
 666
 667 extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
 668
 669 /**
 670  * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object.
 671  *
 672  * @vma:       vma as input from the fbdev mmap method.
 673  * @bo:        The bo backing the address space. The address space will
 674  * have the same size as the bo, and start at offset 0.
 675  *
 676  * This function is intended to be called by the fbdev mmap method
 677  * if the fbdev address space is to be backed by a bo.
 678  */
 679
 680 extern int ttm_fbdev_mmap(struct vm_area_struct *vma,
 681                           struct ttm_buffer_object *bo);
 682
 683 /**
 684  * ttm_bo_mmap - mmap out of the ttm device address space.
 685  *
 686  * @filp:      filp as input from the mmap method.
 687  * @vma:       vma as input from the mmap method.
 688  * @bdev:      Pointer to the ttm_bo_device with the address space manager.
 689  *
 690  * This function is intended to be called by the device mmap method.
 691  * if the device address space is to be backed by the bo manager.
 692  */
 693
 694 extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
 695                        struct ttm_bo_device *bdev);
 696
 697 /**
 698  * ttm_bo_io
 699  *
 700  * @bdev:      Pointer to the struct ttm_bo_device.
 701  * @filp:      Pointer to the struct file attempting to read / write.
 702  * @wbuf:      User-space pointer to address of buffer to write. NULL on read.
 703  * @rbuf:      User-space pointer to address of buffer to read into.
 704  * Null on write.
 705  * @count:     Number of bytes to read / write.
 706  * @f_pos:     Pointer to current file position.
 707  * @write:     1 for read, 0 for write.
 708  *
 709  * This function implements read / write into ttm buffer objects, and is
 710  * intended to
 711  * be called from the fops::read and fops::write method.
 712  * Returns:
 713  * See man (2) write, man(2) read. In particular,
 714  * the function may return -ERESTARTSYS if
 715  * interrupted by a signal.
 716  */
 717
 718 extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
 719                          const char __user *wbuf, char __user *rbuf,
 720                          size_t count, loff_t *f_pos, bool write);
 721
 722 extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
 723 extern int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo);
 724 #endif