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 /* $FreeBSD: head/sys/dev/drm2/ttm/ttm_bo_api.h 247835 2013-03-05 09:49:34Z kib $ */ 31 32 #ifndef _TTM_BO_API_H_ 33 #define _TTM_BO_API_H_ 34 35 #include <drm/drmP.h> 36 #include <drm/drm_hashtab.h> 37 #include <linux/kref.h> 38 #include <linux/list.h> 39 #include <linux/wait.h> 40 #include <linux/mutex.h> 41 #include <linux/reservation.h> 42 43 struct ttm_bo_device; 44 45 struct drm_mm_node; 46 47 48 /** 49 * struct ttm_placement 50 * 51 * @fpfn: first valid page frame number to put the object 52 * @lpfn: last valid page frame number to put the object 53 * @num_placement: number of preferred placements 54 * @placement: preferred placements 55 * @num_busy_placement: number of preferred placements when need to evict buffer 56 * @busy_placement: preferred placements when need to evict buffer 57 * 58 * Structure indicating the placement you request for an object. 59 */ 60 struct ttm_placement { 61 unsigned fpfn; 62 unsigned lpfn; 63 unsigned num_placement; 64 const uint32_t *placement; 65 unsigned num_busy_placement; 66 const uint32_t *busy_placement; 67 }; 68 69 /** 70 * struct ttm_bus_placement 71 * 72 * @addr: mapped virtual address 73 * @base: bus base address 74 * @is_iomem: is this io memory ? 75 * @size: size in byte 76 * @offset: offset from the base address 77 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count 78 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve 79 * 80 * Structure indicating the bus placement of an object. 81 */ 82 struct ttm_bus_placement { 83 void *addr; 84 unsigned long base; 85 unsigned long size; 86 unsigned long offset; 87 bool is_iomem; 88 bool io_reserved_vm; 89 uint64_t io_reserved_count; 90 }; 91 92 93 /** 94 * struct ttm_mem_reg 95 * 96 * @mm_node: Memory manager node. 97 * @size: Requested size of memory region. 98 * @num_pages: Actual size of memory region in pages. 99 * @page_alignment: Page alignment. 100 * @placement: Placement flags. 101 * @bus: Placement on io bus accessible to the CPU 102 * 103 * Structure indicating the placement and space resources used by a 104 * buffer object. 105 */ 106 107 struct ttm_mem_reg { 108 void *mm_node; 109 unsigned long start; 110 unsigned long size; 111 unsigned long num_pages; 112 uint32_t page_alignment; 113 uint32_t mem_type; 114 uint32_t placement; 115 struct ttm_bus_placement bus; 116 }; 117 118 /** 119 * enum ttm_bo_type 120 * 121 * @ttm_bo_type_device: These are 'normal' buffers that can 122 * be mmapped by user space. Each of these bos occupy a slot in the 123 * device address space, that can be used for normal vm operations. 124 * 125 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers, 126 * but they cannot be accessed from user-space. For kernel-only use. 127 * 128 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another 129 * driver. 130 */ 131 132 enum ttm_bo_type { 133 ttm_bo_type_device, 134 ttm_bo_type_kernel, 135 ttm_bo_type_sg 136 }; 137 138 struct ttm_tt; 139 140 /** 141 * struct ttm_buffer_object 142 * 143 * @bdev: Pointer to the buffer object device structure. 144 * @type: The bo type. 145 * @destroy: Destruction function. If NULL, kfree is used. 146 * @num_pages: Actual number of pages. 147 * @addr_space_offset: Address space offset. 148 * @acc_size: Accounted size for this object. 149 * @kref: Reference count of this buffer object. When this refcount reaches 150 * zero, the object is put on the delayed delete list. 151 * @list_kref: List reference count of this buffer object. This member is 152 * used to avoid destruction while the buffer object is still on a list. 153 * Lru lists may keep one refcount, the delayed delete list, and kref != 0 154 * keeps one refcount. When this refcount reaches zero, 155 * the object is destroyed. 156 * @event_queue: Queue for processes waiting on buffer object status change. 157 * @mem: structure describing current placement. 158 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 159 * pinned in physical memory. If this behaviour is not desired, this member 160 * holds a pointer to a persistent shmem object. 161 * @ttm: TTM structure holding system pages. 162 * @evicted: Whether the object was evicted without user-space knowing. 163 * @cpu_writes: For synchronization. Number of cpu writers. 164 * @lru: List head for the lru list. 165 * @ddestroy: List head for the delayed destroy list. 166 * @swap: List head for swap LRU list. 167 * @val_seq: Sequence of the validation holding the @reserved lock. 168 * Used to avoid starvation when many processes compete to validate the 169 * buffer. This member is protected by the bo_device::lru_lock. 170 * @seq_valid: The value of @val_seq is valid. This value is protected by 171 * the bo_device::lru_lock. 172 * @reserved: Deadlock-free lock used for synchronization state transitions. 173 * @sync_obj: Pointer to a synchronization object. 174 * @priv_flags: Flags describing buffer object internal state. 175 * @vm_rb: Rb node for the vm rb tree. 176 * @vm_node: Address space manager node. 177 * @offset: The current GPU offset, which can have different meanings 178 * depending on the memory type. For SYSTEM type memory, it should be 0. 179 * @cur_placement: Hint of current placement. 180 * 181 * Base class for TTM buffer object, that deals with data placement and CPU 182 * mappings. GPU mappings are really up to the driver, but for simpler GPUs 183 * the driver can usually use the placement offset @offset directly as the 184 * GPU virtual address. For drivers implementing multiple 185 * GPU memory manager contexts, the driver should manage the address space 186 * in these contexts separately and use these objects to get the correct 187 * placement and caching for these GPU maps. This makes it possible to use 188 * these objects for even quite elaborate memory management schemes. 189 * The destroy member, the API visibility of this object makes it possible 190 * to derive driver specific types. 191 */ 192 193 struct ttm_buffer_object { 194 /** 195 * Members constant at init. 196 */ 197 198 struct ttm_bo_global *glob; 199 struct ttm_bo_device *bdev; 200 enum ttm_bo_type type; 201 void (*destroy) (struct ttm_buffer_object *); 202 unsigned long num_pages; 203 uint64_t addr_space_offset; 204 size_t acc_size; 205 206 /** 207 * Members not needing protection. 208 */ 209 210 struct kref kref; 211 struct kref list_kref; 212 213 wait_queue_head_t event_queue; 214 215 /** 216 * Members protected by the bo::reserved lock. 217 */ 218 219 struct ttm_mem_reg mem; 220 struct vm_object *persistent_swap_storage; 221 struct ttm_tt *ttm; 222 bool evicted; 223 224 /** 225 * Members protected by the bo::reserved lock only when written to. 226 */ 227 228 atomic_t cpu_writers; 229 230 /** 231 * Members protected by the bdev::lru_lock. 232 */ 233 234 struct list_head lru; 235 struct list_head ddestroy; 236 struct list_head swap; 237 struct list_head io_reserve_lru; 238 unsigned long val_seq; 239 bool seq_valid; 240 241 /** 242 * Members protected by the bdev::lru_lock 243 * only when written to. 244 */ 245 246 atomic_t reserved; 247 248 /** 249 * Members protected by struct buffer_object_device::fence_lock 250 * In addition, setting sync_obj to anything else 251 * than NULL requires bo::reserved to be held. This allows for 252 * checking NULL while reserved but not holding the mentioned lock. 253 */ 254 255 void *sync_obj; 256 unsigned long priv_flags; 257 258 /** 259 * Members protected by the bdev::vm_lock 260 */ 261 262 RB_ENTRY(ttm_buffer_object) vm_rb; 263 struct drm_mm_node *vm_node; 264 265 266 /** 267 * Special members that are protected by the reserve lock 268 * and the bo::lock when written to. Can be read with 269 * either of these locks held. 270 */ 271 272 unsigned long offset; 273 uint32_t cur_placement; 274 275 struct sg_table *sg; 276 }; 277 278 /** 279 * struct ttm_bo_kmap_obj 280 * 281 * @virtual: The current kernel virtual address. 282 * @page: The page when kmap'ing a single page. 283 * @bo_kmap_type: Type of bo_kmap. 284 * 285 * Object describing a kernel mapping. Since a TTM bo may be located 286 * in various memory types with various caching policies, the 287 * mapping can either be an ioremap, a vmap, a kmap or part of a 288 * premapped region. 289 */ 290 291 #define TTM_BO_MAP_IOMEM_MASK 0x80 292 struct ttm_bo_kmap_obj { 293 void *virtual; 294 struct vm_page *page; 295 struct sf_buf *sf; 296 int num_pages; 297 unsigned long size; 298 enum { 299 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK, 300 ttm_bo_map_vmap = 2, 301 ttm_bo_map_kmap = 3, 302 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK, 303 } bo_kmap_type; 304 struct ttm_buffer_object *bo; 305 }; 306 307 /** 308 * ttm_bo_reference - reference a struct ttm_buffer_object 309 * 310 * @bo: The buffer object. 311 * 312 * Returns a refcounted pointer to a buffer object. 313 */ 314 315 static inline struct ttm_buffer_object * 316 ttm_bo_reference(struct ttm_buffer_object *bo) 317 { 318 kref_get(&bo->kref); 319 return bo; 320 } 321 322 /** 323 * ttm_bo_wait - wait for buffer idle. 324 * 325 * @bo: The buffer object. 326 * @interruptible: Use interruptible wait. 327 * @no_wait: Return immediately if buffer is busy. 328 * 329 * This function must be called with the bo::mutex held, and makes 330 * sure any previous rendering to the buffer is completed. 331 * Note: It might be necessary to block validations before the 332 * wait by reserving the buffer. 333 * Returns -EBUSY if no_wait is true and the buffer is busy. 334 * Returns -ERESTARTSYS if interrupted by a signal. 335 */ 336 extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy, 337 bool interruptible, bool no_wait); 338 /** 339 * ttm_bo_validate 340 * 341 * @bo: The buffer object. 342 * @placement: Proposed placement for the buffer object. 343 * @interruptible: Sleep interruptible if sleeping. 344 * @no_wait_gpu: Return immediately if the GPU is busy. 345 * 346 * Changes placement and caching policy of the buffer object 347 * according proposed placement. 348 * Returns 349 * -EINVAL on invalid proposed placement. 350 * -ENOMEM on out-of-memory condition. 351 * -EBUSY if no_wait is true and buffer busy. 352 * -ERESTARTSYS if interrupted by a signal. 353 */ 354 extern int ttm_bo_validate(struct ttm_buffer_object *bo, 355 struct ttm_placement *placement, 356 bool interruptible, 357 bool no_wait_gpu); 358 359 /** 360 * ttm_bo_unref 361 * 362 * @bo: The buffer object. 363 * 364 * Unreference and clear a pointer to a buffer object. 365 */ 366 extern void ttm_bo_unref(struct ttm_buffer_object **bo); 367 368 369 /** 370 * ttm_bo_list_ref_sub 371 * 372 * @bo: The buffer object. 373 * @count: The number of references with which to decrease @bo::list_kref; 374 * @never_free: The refcount should not reach zero with this operation. 375 * 376 * Release @count lru list references to this buffer object. 377 */ 378 extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count, 379 bool never_free); 380 381 /** 382 * ttm_bo_add_to_lru 383 * 384 * @bo: The buffer object. 385 * 386 * Add this bo to the relevant mem type lru and, if it's backed by 387 * system pages (ttms) to the swap list. 388 * This function must be called with struct ttm_bo_global::lru_lock held, and 389 * is typically called immediately prior to unreserving a bo. 390 */ 391 extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo); 392 393 /** 394 * ttm_bo_del_from_lru 395 * 396 * @bo: The buffer object. 397 * 398 * Remove this bo from all lru lists used to lookup and reserve an object. 399 * This function must be called with struct ttm_bo_global::lru_lock held, 400 * and is usually called just immediately after the bo has been reserved to 401 * avoid recursive reservation from lru lists. 402 */ 403 extern int ttm_bo_del_from_lru(struct ttm_buffer_object *bo); 404 405 406 /** 407 * ttm_bo_lock_delayed_workqueue 408 * 409 * Prevent the delayed workqueue from running. 410 * Returns 411 * True if the workqueue was queued at the time 412 */ 413 extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev); 414 415 /** 416 * ttm_bo_unlock_delayed_workqueue 417 * 418 * Allows the delayed workqueue to run. 419 */ 420 extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, 421 int resched); 422 423 /** 424 * ttm_bo_synccpu_write_grab 425 * 426 * @bo: The buffer object: 427 * @no_wait: Return immediately if buffer is busy. 428 * 429 * Synchronizes a buffer object for CPU RW access. This means 430 * command submission that affects the buffer will return -EBUSY 431 * until ttm_bo_synccpu_write_release is called. 432 * 433 * Returns 434 * -EBUSY if the buffer is busy and no_wait is true. 435 * -ERESTARTSYS if interrupted by a signal. 436 */ 437 extern int 438 ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait); 439 440 /** 441 * ttm_bo_synccpu_write_release: 442 * 443 * @bo : The buffer object. 444 * 445 * Releases a synccpu lock. 446 */ 447 extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo); 448 449 /** 450 * ttm_bo_acc_size 451 * 452 * @bdev: Pointer to a ttm_bo_device struct. 453 * @bo_size: size of the buffer object in byte. 454 * @struct_size: size of the structure holding buffer object datas 455 * 456 * Returns size to account for a buffer object 457 */ 458 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev, 459 unsigned long bo_size, 460 unsigned struct_size); 461 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev, 462 unsigned long bo_size, 463 unsigned struct_size); 464 465 /** 466 * ttm_bo_init 467 * 468 * @bdev: Pointer to a ttm_bo_device struct. 469 * @bo: Pointer to a ttm_buffer_object to be initialized. 470 * @size: Requested size of buffer object. 471 * @type: Requested type of buffer object. 472 * @flags: Initial placement flags. 473 * @page_alignment: Data alignment in pages. 474 * @interruptible: If needing to sleep to wait for GPU resources, 475 * sleep interruptible. 476 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 477 * pinned in physical memory. If this behaviour is not desired, this member 478 * holds a pointer to a persistent shmem object. Typically, this would 479 * point to the shmem object backing a GEM object if TTM is used to back a 480 * GEM user interface. 481 * @acc_size: Accounted size for this object. 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 void (*destroy) (struct ttm_buffer_object *)); 510 511 /** 512 * ttm_bo_create 513 * 514 * @bdev: Pointer to a ttm_bo_device struct. 515 * @size: Requested size of buffer object. 516 * @type: Requested type of buffer object. 517 * @placement: Initial placement. 518 * @page_alignment: Data alignment in pages. 519 * @interruptible: If needing to sleep while waiting for GPU resources, 520 * sleep interruptible. 521 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 522 * pinned in physical memory. If this behaviour is not desired, this member 523 * holds a pointer to a persistent shmem object. Typically, this would 524 * point to the shmem object backing a GEM object if TTM is used to back a 525 * GEM user interface. 526 * @p_bo: On successful completion *p_bo points to the created object. 527 * 528 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init 529 * on that object. The destroy function is set to kfree(). 530 * Returns 531 * -ENOMEM: Out of memory. 532 * -EINVAL: Invalid placement flags. 533 * -ERESTARTSYS: Interrupted by signal while waiting for resources. 534 */ 535 536 extern int ttm_bo_create(struct ttm_bo_device *bdev, 537 unsigned long size, 538 enum ttm_bo_type type, 539 struct ttm_placement *placement, 540 uint32_t page_alignment, 541 bool interruptible, 542 struct vm_object *persistent_swap_storage, 543 struct ttm_buffer_object **p_bo); 544 545 /** 546 * ttm_bo_check_placement 547 * 548 * @bo: the buffer object. 549 * @placement: placements 550 * 551 * Performs minimal validity checking on an intended change of 552 * placement flags. 553 * Returns 554 * -EINVAL: Intended change is invalid or not allowed. 555 */ 556 extern int ttm_bo_check_placement(struct ttm_buffer_object *bo, 557 struct ttm_placement *placement); 558 559 /** 560 * ttm_bo_init_mm 561 * 562 * @bdev: Pointer to a ttm_bo_device struct. 563 * @mem_type: The memory type. 564 * @p_size: size managed area in pages. 565 * 566 * Initialize a manager for a given memory type. 567 * Note: if part of driver firstopen, it must be protected from a 568 * potentially racing lastclose. 569 * Returns: 570 * -EINVAL: invalid size or memory type. 571 * -ENOMEM: Not enough memory. 572 * May also return driver-specified errors. 573 */ 574 575 extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type, 576 unsigned long p_size); 577 /** 578 * ttm_bo_clean_mm 579 * 580 * @bdev: Pointer to a ttm_bo_device struct. 581 * @mem_type: The memory type. 582 * 583 * Take down a manager for a given memory type after first walking 584 * the LRU list to evict any buffers left alive. 585 * 586 * Normally, this function is part of lastclose() or unload(), and at that 587 * point there shouldn't be any buffers left created by user-space, since 588 * there should've been removed by the file descriptor release() method. 589 * However, before this function is run, make sure to signal all sync objects, 590 * and verify that the delayed delete queue is empty. The driver must also 591 * make sure that there are no NO_EVICT buffers present in this memory type 592 * when the call is made. 593 * 594 * If this function is part of a VT switch, the caller must make sure that 595 * there are no appications currently validating buffers before this 596 * function is called. The caller can do that by first taking the 597 * struct ttm_bo_device::ttm_lock in write mode. 598 * 599 * Returns: 600 * -EINVAL: invalid or uninitialized memory type. 601 * -EBUSY: There are still buffers left in this memory type. 602 */ 603 604 extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type); 605 606 /** 607 * ttm_bo_evict_mm 608 * 609 * @bdev: Pointer to a ttm_bo_device struct. 610 * @mem_type: The memory type. 611 * 612 * Evicts all buffers on the lru list of the memory type. 613 * This is normally part of a VT switch or an 614 * out-of-memory-space-due-to-fragmentation handler. 615 * The caller must make sure that there are no other processes 616 * currently validating buffers, and can do that by taking the 617 * struct ttm_bo_device::ttm_lock in write mode. 618 * 619 * Returns: 620 * -EINVAL: Invalid or uninitialized memory type. 621 * -ERESTARTSYS: The call was interrupted by a signal while waiting to 622 * evict a buffer. 623 */ 624 625 extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type); 626 627 /** 628 * ttm_kmap_obj_virtual 629 * 630 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap. 631 * @is_iomem: Pointer to an integer that on return indicates 1 if the 632 * virtual map is io memory, 0 if normal memory. 633 * 634 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap. 635 * If *is_iomem is 1 on return, the virtual address points to an io memory area, 636 * that should strictly be accessed by the iowriteXX() and similar functions. 637 */ 638 639 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, 640 bool *is_iomem) 641 { 642 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK); 643 return map->virtual; 644 } 645 646 /** 647 * ttm_bo_kmap 648 * 649 * @bo: The buffer object. 650 * @start_page: The first page to map. 651 * @num_pages: Number of pages to map. 652 * @map: pointer to a struct ttm_bo_kmap_obj representing the map. 653 * 654 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the 655 * data in the buffer object. The ttm_kmap_obj_virtual function can then be 656 * used to obtain a virtual address to the data. 657 * 658 * Returns 659 * -ENOMEM: Out of memory. 660 * -EINVAL: Invalid range. 661 */ 662 663 extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, 664 unsigned long num_pages, struct ttm_bo_kmap_obj *map); 665 666 /** 667 * ttm_bo_kunmap 668 * 669 * @map: Object describing the map to unmap. 670 * 671 * Unmaps a kernel map set up by ttm_bo_kmap. 672 */ 673 674 extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); 675 676 /** 677 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object. 678 * 679 * @vma: vma as input from the fbdev mmap method. 680 * @bo: The bo backing the address space. The address space will 681 * have the same size as the bo, and start at offset 0. 682 * 683 * This function is intended to be called by the fbdev mmap method 684 * if the fbdev address space is to be backed by a bo. 685 */ 686 687 /* XXXKIB 688 extern int ttm_fbdev_mmap(struct vm_area_struct *vma, 689 struct ttm_buffer_object *bo); 690 */ 691 /** 692 * ttm_bo_mmap - mmap out of the ttm device address space. 693 * 694 * @filp: filp as input from the mmap method. 695 * @vma: vma as input from the mmap method. 696 * @bdev: Pointer to the ttm_bo_device with the address space manager. 697 * 698 * This function is intended to be called by the device mmap method. 699 * if the device address space is to be backed by the bo manager. 700 */ 701 /* XXXKIB 702 extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, 703 struct ttm_bo_device *bdev); 704 */ 705 /** 706 * ttm_bo_io 707 * 708 * @bdev: Pointer to the struct ttm_bo_device. 709 * @filp: Pointer to the struct file attempting to read / write. 710 * @wbuf: User-space pointer to address of buffer to write. NULL on read. 711 * @rbuf: User-space pointer to address of buffer to read into. 712 * Null on write. 713 * @count: Number of bytes to read / write. 714 * @f_pos: Pointer to current file position. 715 * @write: 1 for read, 0 for write. 716 * 717 * This function implements read / write into ttm buffer objects, and is 718 * intended to 719 * be called from the fops::read and fops::write method. 720 * Returns: 721 * See man (2) write, man(2) read. In particular, 722 * the function may return -ERESTARTSYS if 723 * interrupted by a signal. 724 */ 725 726 extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp, 727 const char *wbuf, char *rbuf, 728 size_t count, off_t *f_pos, bool write); 729 730 extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev); 731 732 /** 733 * ttm_bo_is_reserved - return an indication if a ttm buffer object is reserved 734 * 735 * @bo: The buffer object to check. 736 * 737 * This function returns an indication if a bo is reserved or not, and should 738 * only be used to print an error when it is not from incorrect api usage, since 739 * there's no guarantee that it is the caller that is holding the reservation. 740 */ 741 static inline bool ttm_bo_is_reserved(struct ttm_buffer_object *bo) 742 { 743 return atomic_read(&bo->reserved); 744 } 745 746 #endif 747