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/rbtree.h> 40 41 struct ttm_bo_device; 42 43 struct drm_mm_node; 44 45 46 /** 47 * struct ttm_placement 48 * 49 * @fpfn: first valid page frame number to put the object 50 * @lpfn: last valid page frame number to put the object 51 * @num_placement: number of preferred placements 52 * @placement: preferred placements 53 * @num_busy_placement: number of preferred placements when need to evict buffer 54 * @busy_placement: preferred placements when need to evict buffer 55 * 56 * Structure indicating the placement you request for an object. 57 */ 58 struct ttm_placement { 59 unsigned fpfn; 60 unsigned lpfn; 61 unsigned num_placement; 62 const uint32_t *placement; 63 unsigned num_busy_placement; 64 const uint32_t *busy_placement; 65 }; 66 67 /** 68 * struct ttm_bus_placement 69 * 70 * @addr: mapped virtual address 71 * @base: bus base address 72 * @is_iomem: is this io memory ? 73 * @size: size in byte 74 * @offset: offset from the base address 75 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count 76 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve 77 * 78 * Structure indicating the bus placement of an object. 79 */ 80 struct ttm_bus_placement { 81 void *addr; 82 unsigned long base; 83 unsigned long size; 84 unsigned long offset; 85 bool is_iomem; 86 bool io_reserved_vm; 87 uint64_t io_reserved_count; 88 }; 89 90 91 /** 92 * struct ttm_mem_reg 93 * 94 * @mm_node: Memory manager node. 95 * @size: Requested size of memory region. 96 * @num_pages: Actual size of memory region in pages. 97 * @page_alignment: Page alignment. 98 * @placement: Placement flags. 99 * @bus: Placement on io bus accessible to the CPU 100 * 101 * Structure indicating the placement and space resources used by a 102 * buffer object. 103 */ 104 105 struct ttm_mem_reg { 106 void *mm_node; 107 unsigned long start; 108 unsigned long size; 109 unsigned long num_pages; 110 uint32_t page_alignment; 111 uint32_t mem_type; 112 uint32_t placement; 113 struct ttm_bus_placement bus; 114 }; 115 116 /** 117 * enum ttm_bo_type 118 * 119 * @ttm_bo_type_device: These are 'normal' buffers that can 120 * be mmapped by user space. Each of these bos occupy a slot in the 121 * device address space, that can be used for normal vm operations. 122 * 123 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers, 124 * but they cannot be accessed from user-space. For kernel-only use. 125 * 126 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another 127 * driver. 128 */ 129 130 enum ttm_bo_type { 131 ttm_bo_type_device, 132 ttm_bo_type_kernel, 133 ttm_bo_type_sg 134 }; 135 136 struct ttm_tt; 137 138 /** 139 * struct ttm_buffer_object 140 * 141 * @bdev: Pointer to the buffer object device structure. 142 * @type: The bo type. 143 * @destroy: Destruction function. If NULL, kfree is used. 144 * @num_pages: Actual number of pages. 145 * @addr_space_offset: Address space offset. 146 * @acc_size: Accounted size for this object. 147 * @kref: Reference count of this buffer object. When this refcount reaches 148 * zero, the object is put on the delayed delete list. 149 * @list_kref: List reference count of this buffer object. This member is 150 * used to avoid destruction while the buffer object is still on a list. 151 * Lru lists may keep one refcount, the delayed delete list, and kref != 0 152 * keeps one refcount. When this refcount reaches zero, 153 * the object is destroyed. 154 * @event_queue: Queue for processes waiting on buffer object status change. 155 * @mem: structure describing current placement. 156 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 157 * pinned in physical memory. If this behaviour is not desired, this member 158 * holds a pointer to a persistent shmem object. 159 * @ttm: TTM structure holding system pages. 160 * @evicted: Whether the object was evicted without user-space knowing. 161 * @cpu_writes: For synchronization. Number of cpu writers. 162 * @lru: List head for the lru list. 163 * @ddestroy: List head for the delayed destroy list. 164 * @swap: List head for swap LRU list. 165 * @val_seq: Sequence of the validation holding the @reserved lock. 166 * Used to avoid starvation when many processes compete to validate the 167 * buffer. This member is protected by the bo_device::lru_lock. 168 * @seq_valid: The value of @val_seq is valid. This value is protected by 169 * the bo_device::lru_lock. 170 * @reserved: Deadlock-free lock used for synchronization state transitions. 171 * @sync_obj: Pointer to a synchronization object. 172 * @priv_flags: Flags describing buffer object internal state. 173 * @vm_rb: Rb node for the vm rb tree. 174 * @vm_node: Address space manager node. 175 * @offset: The current GPU offset, which can have different meanings 176 * depending on the memory type. For SYSTEM type memory, it should be 0. 177 * @cur_placement: Hint of current placement. 178 * 179 * Base class for TTM buffer object, that deals with data placement and CPU 180 * mappings. GPU mappings are really up to the driver, but for simpler GPUs 181 * the driver can usually use the placement offset @offset directly as the 182 * GPU virtual address. For drivers implementing multiple 183 * GPU memory manager contexts, the driver should manage the address space 184 * in these contexts separately and use these objects to get the correct 185 * placement and caching for these GPU maps. This makes it possible to use 186 * these objects for even quite elaborate memory management schemes. 187 * The destroy member, the API visibility of this object makes it possible 188 * to derive driver specific types. 189 */ 190 191 struct ttm_buffer_object { 192 /** 193 * Members constant at init. 194 */ 195 196 struct ttm_bo_global *glob; 197 struct ttm_bo_device *bdev; 198 enum ttm_bo_type type; 199 void (*destroy) (struct ttm_buffer_object *); 200 unsigned long num_pages; 201 uint64_t addr_space_offset; 202 size_t acc_size; 203 204 /** 205 * Members not needing protection. 206 */ 207 208 struct kref kref; 209 struct kref list_kref; 210 211 wait_queue_head_t event_queue; 212 213 /** 214 * Members protected by the bo::reserved lock. 215 */ 216 217 struct ttm_mem_reg mem; 218 struct vm_object *persistent_swap_storage; 219 struct ttm_tt *ttm; 220 bool evicted; 221 222 /** 223 * Members protected by the bo::reserved lock only when written to. 224 */ 225 226 atomic_t cpu_writers; 227 228 /** 229 * Members protected by the bdev::lru_lock. 230 */ 231 232 struct list_head lru; 233 struct list_head ddestroy; 234 struct list_head swap; 235 struct list_head io_reserve_lru; 236 uint32_t val_seq; 237 bool seq_valid; 238 239 /** 240 * Members protected by the bdev::lru_lock 241 * only when written to. 242 */ 243 244 atomic_t reserved; 245 246 /** 247 * Members protected by struct buffer_object_device::fence_lock 248 * In addition, setting sync_obj to anything else 249 * than NULL requires bo::reserved to be held. This allows for 250 * checking NULL while reserved but not holding the mentioned lock. 251 */ 252 253 void *sync_obj; 254 unsigned long priv_flags; 255 256 /** 257 * Members protected by the bdev::vm_lock 258 */ 259 260 struct rb_node vm_rb; 261 struct drm_mm_node *vm_node; 262 263 264 /** 265 * Special members that are protected by the reserve lock 266 * and the bo::lock when written to. Can be read with 267 * either of these locks held. 268 */ 269 270 unsigned long offset; 271 uint32_t cur_placement; 272 273 struct sg_table *sg; 274 }; 275 276 /** 277 * struct ttm_bo_kmap_obj 278 * 279 * @virtual: The current kernel virtual address. 280 * @page: The page when kmap'ing a single page. 281 * @bo_kmap_type: Type of bo_kmap. 282 * 283 * Object describing a kernel mapping. Since a TTM bo may be located 284 * in various memory types with various caching policies, the 285 * mapping can either be an ioremap, a vmap, a kmap or part of a 286 * premapped region. 287 */ 288 289 #define TTM_BO_MAP_IOMEM_MASK 0x80 290 struct ttm_bo_kmap_obj { 291 void *virtual; 292 struct vm_page *page; 293 struct sf_buf *sf; 294 int num_pages; 295 unsigned long size; 296 enum { 297 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK, 298 ttm_bo_map_vmap = 2, 299 ttm_bo_map_kmap = 3, 300 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK, 301 } bo_kmap_type; 302 struct ttm_buffer_object *bo; 303 }; 304 305 /** 306 * ttm_bo_reference - reference a struct ttm_buffer_object 307 * 308 * @bo: The buffer object. 309 * 310 * Returns a refcounted pointer to a buffer object. 311 */ 312 313 static inline struct ttm_buffer_object * 314 ttm_bo_reference(struct ttm_buffer_object *bo) 315 { 316 kref_get(&bo->kref); 317 return bo; 318 } 319 320 /** 321 * ttm_bo_wait - wait for buffer idle. 322 * 323 * @bo: The buffer object. 324 * @interruptible: Use interruptible wait. 325 * @no_wait: Return immediately if buffer is busy. 326 * 327 * This function must be called with the bo::mutex held, and makes 328 * sure any previous rendering to the buffer is completed. 329 * Note: It might be necessary to block validations before the 330 * wait by reserving the buffer. 331 * Returns -EBUSY if no_wait is true and the buffer is busy. 332 * Returns -ERESTARTSYS if interrupted by a signal. 333 */ 334 extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy, 335 bool interruptible, bool no_wait); 336 /** 337 * ttm_bo_validate 338 * 339 * @bo: The buffer object. 340 * @placement: Proposed placement for the buffer object. 341 * @interruptible: Sleep interruptible if sleeping. 342 * @no_wait_gpu: Return immediately if the GPU is busy. 343 * 344 * Changes placement and caching policy of the buffer object 345 * according proposed placement. 346 * Returns 347 * -EINVAL on invalid proposed placement. 348 * -ENOMEM on out-of-memory condition. 349 * -EBUSY if no_wait is true and buffer busy. 350 * -ERESTARTSYS if interrupted by a signal. 351 */ 352 extern int ttm_bo_validate(struct ttm_buffer_object *bo, 353 struct ttm_placement *placement, 354 bool interruptible, 355 bool no_wait_gpu); 356 357 /** 358 * ttm_bo_unref 359 * 360 * @bo: The buffer object. 361 * 362 * Unreference and clear a pointer to a buffer object. 363 */ 364 extern void ttm_bo_unref(struct ttm_buffer_object **bo); 365 366 367 /** 368 * ttm_bo_list_ref_sub 369 * 370 * @bo: The buffer object. 371 * @count: The number of references with which to decrease @bo::list_kref; 372 * @never_free: The refcount should not reach zero with this operation. 373 * 374 * Release @count lru list references to this buffer object. 375 */ 376 extern void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count, 377 bool never_free); 378 379 /** 380 * ttm_bo_add_to_lru 381 * 382 * @bo: The buffer object. 383 * 384 * Add this bo to the relevant mem type lru and, if it's backed by 385 * system pages (ttms) to the swap list. 386 * This function must be called with struct ttm_bo_global::lru_lock held, and 387 * is typically called immediately prior to unreserving a bo. 388 */ 389 extern void ttm_bo_add_to_lru(struct ttm_buffer_object *bo); 390 391 /** 392 * ttm_bo_del_from_lru 393 * 394 * @bo: The buffer object. 395 * 396 * Remove this bo from all lru lists used to lookup and reserve an object. 397 * This function must be called with struct ttm_bo_global::lru_lock held, 398 * and is usually called just immediately after the bo has been reserved to 399 * avoid recursive reservation from lru lists. 400 */ 401 extern int ttm_bo_del_from_lru(struct ttm_buffer_object *bo); 402 403 404 /** 405 * ttm_bo_lock_delayed_workqueue 406 * 407 * Prevent the delayed workqueue from running. 408 * Returns 409 * True if the workqueue was queued at the time 410 */ 411 extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev); 412 413 /** 414 * ttm_bo_unlock_delayed_workqueue 415 * 416 * Allows the delayed workqueue to run. 417 */ 418 extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, 419 int resched); 420 421 /** 422 * ttm_bo_synccpu_write_grab 423 * 424 * @bo: The buffer object: 425 * @no_wait: Return immediately if buffer is busy. 426 * 427 * Synchronizes a buffer object for CPU RW access. This means 428 * command submission that affects the buffer will return -EBUSY 429 * until ttm_bo_synccpu_write_release is called. 430 * 431 * Returns 432 * -EBUSY if the buffer is busy and no_wait is true. 433 * -ERESTARTSYS if interrupted by a signal. 434 */ 435 extern int 436 ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait); 437 438 /** 439 * ttm_bo_synccpu_write_release: 440 * 441 * @bo : The buffer object. 442 * 443 * Releases a synccpu lock. 444 */ 445 extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo); 446 447 /** 448 * ttm_bo_acc_size 449 * 450 * @bdev: Pointer to a ttm_bo_device struct. 451 * @bo_size: size of the buffer object in byte. 452 * @struct_size: size of the structure holding buffer object datas 453 * 454 * Returns size to account for a buffer object 455 */ 456 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev, 457 unsigned long bo_size, 458 unsigned struct_size); 459 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev, 460 unsigned long bo_size, 461 unsigned struct_size); 462 463 /** 464 * ttm_bo_init 465 * 466 * @bdev: Pointer to a ttm_bo_device struct. 467 * @bo: Pointer to a ttm_buffer_object to be initialized. 468 * @size: Requested size of buffer object. 469 * @type: Requested type of buffer object. 470 * @flags: Initial placement flags. 471 * @page_alignment: Data alignment in pages. 472 * @interruptible: If needing to sleep to wait for GPU resources, 473 * sleep interruptible. 474 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 475 * pinned in physical memory. If this behaviour is not desired, this member 476 * holds a pointer to a persistent shmem object. Typically, this would 477 * point to the shmem object backing a GEM object if TTM is used to back a 478 * GEM user interface. 479 * @acc_size: Accounted size for this object. 480 * @destroy: Destroy function. Use NULL for kfree(). 481 * 482 * This function initializes a pre-allocated struct ttm_buffer_object. 483 * As this object may be part of a larger structure, this function, 484 * together with the @destroy function, 485 * enables driver-specific objects derived from a ttm_buffer_object. 486 * On successful return, the object kref and list_kref are set to 1. 487 * If a failure occurs, the function will call the @destroy function, or 488 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is 489 * illegal and will likely cause memory corruption. 490 * 491 * Returns 492 * -ENOMEM: Out of memory. 493 * -EINVAL: Invalid placement flags. 494 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 495 */ 496 497 extern int ttm_bo_init(struct ttm_bo_device *bdev, 498 struct ttm_buffer_object *bo, 499 unsigned long size, 500 enum ttm_bo_type type, 501 struct ttm_placement *placement, 502 uint32_t page_alignment, 503 bool interrubtible, 504 struct vm_object *persistent_swap_storage, 505 size_t acc_size, 506 struct sg_table *sg, 507 void (*destroy) (struct ttm_buffer_object *)); 508 509 /** 510 * ttm_bo_synccpu_object_init 511 * 512 * @bdev: Pointer to a ttm_bo_device struct. 513 * @bo: Pointer to a ttm_buffer_object to be initialized. 514 * @size: Requested size of buffer object. 515 * @type: Requested type of buffer object. 516 * @flags: Initial placement flags. 517 * @page_alignment: Data alignment in pages. 518 * @interruptible: If needing to sleep while waiting for GPU resources, 519 * sleep interruptible. 520 * @persistent_swap_storage: Usually the swap storage is deleted for buffers 521 * pinned in physical memory. If this behaviour is not desired, this member 522 * holds a pointer to a persistent shmem object. Typically, this would 523 * point to the shmem object backing a GEM object if TTM is used to back a 524 * GEM user interface. 525 * @p_bo: On successful completion *p_bo points to the created object. 526 * 527 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init 528 * on that object. The destroy function is set to kfree(). 529 * Returns 530 * -ENOMEM: Out of memory. 531 * -EINVAL: Invalid placement flags. 532 * -ERESTARTSYS: Interrupted by signal while waiting for resources. 533 */ 534 535 extern int ttm_bo_create(struct ttm_bo_device *bdev, 536 unsigned long size, 537 enum ttm_bo_type type, 538 struct ttm_placement *placement, 539 uint32_t page_alignment, 540 bool interruptible, 541 struct vm_object *persistent_swap_storage, 542 struct ttm_buffer_object **p_bo); 543 544 /** 545 * ttm_bo_check_placement 546 * 547 * @bo: the buffer object. 548 * @placement: placements 549 * 550 * Performs minimal validity checking on an intended change of 551 * placement flags. 552 * Returns 553 * -EINVAL: Intended change is invalid or not allowed. 554 */ 555 extern int ttm_bo_check_placement(struct ttm_buffer_object *bo, 556 struct ttm_placement *placement); 557 558 /** 559 * ttm_bo_init_mm 560 * 561 * @bdev: Pointer to a ttm_bo_device struct. 562 * @mem_type: The memory type. 563 * @p_size: size managed area in pages. 564 * 565 * Initialize a manager for a given memory type. 566 * Note: if part of driver firstopen, it must be protected from a 567 * potentially racing lastclose. 568 * Returns: 569 * -EINVAL: invalid size or memory type. 570 * -ENOMEM: Not enough memory. 571 * May also return driver-specified errors. 572 */ 573 574 extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type, 575 unsigned long p_size); 576 /** 577 * ttm_bo_clean_mm 578 * 579 * @bdev: Pointer to a ttm_bo_device struct. 580 * @mem_type: The memory type. 581 * 582 * Take down a manager for a given memory type after first walking 583 * the LRU list to evict any buffers left alive. 584 * 585 * Normally, this function is part of lastclose() or unload(), and at that 586 * point there shouldn't be any buffers left created by user-space, since 587 * there should've been removed by the file descriptor release() method. 588 * However, before this function is run, make sure to signal all sync objects, 589 * and verify that the delayed delete queue is empty. The driver must also 590 * make sure that there are no NO_EVICT buffers present in this memory type 591 * when the call is made. 592 * 593 * If this function is part of a VT switch, the caller must make sure that 594 * there are no appications currently validating buffers before this 595 * function is called. The caller can do that by first taking the 596 * struct ttm_bo_device::ttm_lock in write mode. 597 * 598 * Returns: 599 * -EINVAL: invalid or uninitialized memory type. 600 * -EBUSY: There are still buffers left in this memory type. 601 */ 602 603 extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type); 604 605 /** 606 * ttm_bo_evict_mm 607 * 608 * @bdev: Pointer to a ttm_bo_device struct. 609 * @mem_type: The memory type. 610 * 611 * Evicts all buffers on the lru list of the memory type. 612 * This is normally part of a VT switch or an 613 * out-of-memory-space-due-to-fragmentation handler. 614 * The caller must make sure that there are no other processes 615 * currently validating buffers, and can do that by taking the 616 * struct ttm_bo_device::ttm_lock in write mode. 617 * 618 * Returns: 619 * -EINVAL: Invalid or uninitialized memory type. 620 * -ERESTARTSYS: The call was interrupted by a signal while waiting to 621 * evict a buffer. 622 */ 623 624 extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type); 625 626 /** 627 * ttm_kmap_obj_virtual 628 * 629 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap. 630 * @is_iomem: Pointer to an integer that on return indicates 1 if the 631 * virtual map is io memory, 0 if normal memory. 632 * 633 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap. 634 * If *is_iomem is 1 on return, the virtual address points to an io memory area, 635 * that should strictly be accessed by the iowriteXX() and similar functions. 636 */ 637 638 static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, 639 bool *is_iomem) 640 { 641 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK); 642 return map->virtual; 643 } 644 645 /** 646 * ttm_bo_kmap 647 * 648 * @bo: The buffer object. 649 * @start_page: The first page to map. 650 * @num_pages: Number of pages to map. 651 * @map: pointer to a struct ttm_bo_kmap_obj representing the map. 652 * 653 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the 654 * data in the buffer object. The ttm_kmap_obj_virtual function can then be 655 * used to obtain a virtual address to the data. 656 * 657 * Returns 658 * -ENOMEM: Out of memory. 659 * -EINVAL: Invalid range. 660 */ 661 662 extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, 663 unsigned long num_pages, struct ttm_bo_kmap_obj *map); 664 665 /** 666 * ttm_bo_kunmap 667 * 668 * @map: Object describing the map to unmap. 669 * 670 * Unmaps a kernel map set up by ttm_bo_kmap. 671 */ 672 673 extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); 674 675 /** 676 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object. 677 * 678 * @vma: vma as input from the fbdev mmap method. 679 * @bo: The bo backing the address space. The address space will 680 * have the same size as the bo, and start at offset 0. 681 * 682 * This function is intended to be called by the fbdev mmap method 683 * if the fbdev address space is to be backed by a bo. 684 */ 685 686 /* XXXKIB 687 extern int ttm_fbdev_mmap(struct vm_area_struct *vma, 688 struct ttm_buffer_object *bo); 689 */ 690 /** 691 * ttm_bo_mmap - mmap out of the ttm device address space. 692 * 693 * @filp: filp as input from the mmap method. 694 * @vma: vma as input from the mmap method. 695 * @bdev: Pointer to the ttm_bo_device with the address space manager. 696 * 697 * This function is intended to be called by the device mmap method. 698 * if the device address space is to be backed by the bo manager. 699 */ 700 /* XXXKIB 701 extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, 702 struct ttm_bo_device *bdev); 703 */ 704 /** 705 * ttm_bo_io 706 * 707 * @bdev: Pointer to the struct ttm_bo_device. 708 * @filp: Pointer to the struct file attempting to read / write. 709 * @wbuf: User-space pointer to address of buffer to write. NULL on read. 710 * @rbuf: User-space pointer to address of buffer to read into. 711 * Null on write. 712 * @count: Number of bytes to read / write. 713 * @f_pos: Pointer to current file position. 714 * @write: 1 for read, 0 for write. 715 * 716 * This function implements read / write into ttm buffer objects, and is 717 * intended to 718 * be called from the fops::read and fops::write method. 719 * Returns: 720 * See man (2) write, man(2) read. In particular, 721 * the function may return -ERESTARTSYS if 722 * interrupted by a signal. 723 */ 724 725 extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp, 726 const char *wbuf, char *rbuf, 727 size_t count, off_t *f_pos, bool write); 728 729 extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev); 730 731 /** 732 * ttm_bo_is_reserved - return an indication if a ttm buffer object is reserved 733 * 734 * @bo: The buffer object to check. 735 * 736 * This function returns an indication if a bo is reserved or not, and should 737 * only be used to print an error when it is not from incorrect api usage, since 738 * there's no guarantee that it is the caller that is holding the reservation. 739 */ 740 static inline bool ttm_bo_is_reserved(struct ttm_buffer_object *bo) 741 { 742 return atomic_read(&bo->reserved); 743 } 744 745 #endif 746