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_hashtab.h" 35#include <linux/kref.h> 36#include <linux/list.h> 37#include <linux/wait.h> 38#include <linux/mutex.h> 39#include <linux/mm.h> 40#include <linux/rbtree.h> 41#include <linux/bitmap.h> 42 43struct ttm_bo_device; 44 45struct 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 prefered placements 54 * @placement: prefered placements 55 * @num_busy_placement: number of prefered placements when need to evict buffer 56 * @busy_placement: prefered placements when need to evict buffer 57 * 58 * Structure indicating the placement you request for an object. 59 */ 60struct 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 * 78 * Structure indicating the bus placement of an object. 79 */ 80struct 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; 87}; 88 89 90/** 91 * struct ttm_mem_reg 92 * 93 * @mm_node: Memory manager node. 94 * @size: Requested size of memory region. 95 * @num_pages: Actual size of memory region in pages. 96 * @page_alignment: Page alignment. 97 * @placement: Placement flags. 98 * @bus: Placement on io bus accessible to the CPU 99 * 100 * Structure indicating the placement and space resources used by a 101 * buffer object. 102 */ 103 104struct ttm_mem_reg { 105 struct drm_mm_node *mm_node; 106 unsigned long size; 107 unsigned long num_pages; 108 uint32_t page_alignment; 109 uint32_t mem_type; 110 uint32_t placement; 111 struct ttm_bus_placement bus; 112}; 113 114/** 115 * enum ttm_bo_type 116 * 117 * @ttm_bo_type_device: These are 'normal' buffers that can 118 * be mmapped by user space. Each of these bos occupy a slot in the 119 * device address space, that can be used for normal vm operations. 120 * 121 * @ttm_bo_type_user: These are user-space memory areas that are made 122 * available to the GPU by mapping the buffer pages into the GPU aperture 123 * space. These buffers cannot be mmaped from the device address space. 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 129enum ttm_bo_type { 130 ttm_bo_type_device, 131 ttm_bo_type_user, 132 ttm_bo_type_kernel 133}; 134 135struct ttm_tt; 136 137/** 138 * struct ttm_buffer_object 139 * 140 * @bdev: Pointer to the buffer object device structure. 141 * @buffer_start: The virtual user-space start address of ttm_bo_type_user 142 * buffers. 143 * @type: The bo type. 144 * @destroy: Destruction function. If NULL, kfree is used. 145 * @num_pages: Actual number of pages. 146 * @addr_space_offset: Address space offset. 147 * @acc_size: Accounted size for this object. 148 * @kref: Reference count of this buffer object. When this refcount reaches 149 * zero, the object is put on the delayed delete list. 150 * @list_kref: List reference count of this buffer object. This member is 151 * used to avoid destruction while the buffer object is still on a list. 152 * Lru lists may keep one refcount, the delayed delete list, and kref != 0 153 * keeps one refcount. When this refcount reaches zero, 154 * the object is destroyed. 155 * @event_queue: Queue for processes waiting on buffer object status change. 156 * @lock: spinlock protecting mostly synchronization members. 157 * @mem: structure describing current placement. 158 * @persistant_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 persistant 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_arg: Opaque argument to synchronization object function. 174 * @sync_obj: Pointer to a synchronization object. 175 * @priv_flags: Flags describing buffer object internal state. 176 * @vm_rb: Rb node for the vm rb tree. 177 * @vm_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 * 182 * Base class for TTM buffer object, that deals with data placement and CPU 183 * mappings. GPU mappings are really up to the driver, but for simpler GPUs 184 * the driver can usually use the placement offset @offset directly as the 185 * GPU virtual address. For drivers implementing multiple 186 * GPU memory manager contexts, the driver should manage the address space 187 * in these contexts separately and use these objects to get the correct 188 * placement and caching for these GPU maps. This makes it possible to use 189 * these objects for even quite elaborate memory management schemes. 190 * The destroy member, the API visibility of this object makes it possible 191 * to derive driver specific types. 192 */ 193 194struct ttm_buffer_object { 195 /** 196 * Members constant at init. 197 */ 198 199 struct ttm_bo_global *glob; 200 struct ttm_bo_device *bdev; 201 unsigned long buffer_start; 202 enum ttm_bo_type type; 203 void (*destroy) (struct ttm_buffer_object *); 204 unsigned long num_pages; 205 uint64_t addr_space_offset; 206 size_t acc_size; 207 208 /** 209 * Members not needing protection. 210 */ 211 212 struct kref kref; 213 struct kref list_kref; 214 wait_queue_head_t event_queue; 215 spinlock_t lock; 216 217 /** 218 * Members protected by the bo::reserved lock. 219 */ 220 221 struct ttm_mem_reg mem; 222 struct file *persistant_swap_storage; 223 struct ttm_tt *ttm; 224 bool evicted; 225 226 /** 227 * Members protected by the bo::reserved lock only when written to. 228 */ 229 230 atomic_t cpu_writers; 231 232 /** 233 * Members protected by the bdev::lru_lock. 234 */ 235 236 struct list_head lru; 237 struct list_head ddestroy; 238 struct list_head swap; 239 uint32_t val_seq; 240 bool seq_valid; 241 242 /** 243 * Members protected by the bdev::lru_lock 244 * only when written to. 245 */ 246 247 atomic_t reserved; 248 249 /** 250 * Members protected by the bo::lock 251 * In addition, setting sync_obj to anything else 252 * than NULL requires bo::reserved to be held. This allows for 253 * checking NULL while reserved but not holding bo::lock. 254 */ 255 256 void *sync_obj_arg; 257 void *sync_obj; 258 unsigned long priv_flags; 259 260 /** 261 * Members protected by the bdev::vm_lock 262 */ 263 264 struct rb_node vm_rb; 265 struct drm_mm_node *vm_node; 266 267 268 /** 269 * Special members that are protected by the reserve lock 270 * and the bo::lock when written to. Can be read with 271 * either of these locks held. 272 */ 273 274 unsigned long offset; 275 uint32_t cur_placement; 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 292struct ttm_bo_kmap_obj { 293 void *virtual; 294 struct page *page; 295 enum { 296 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK, 297 ttm_bo_map_vmap = 2, 298 ttm_bo_map_kmap = 3, 299 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK, 300 } bo_kmap_type; 301 struct ttm_buffer_object *bo; 302}; 303 304/** 305 * ttm_bo_reference - reference a struct ttm_buffer_object 306 * 307 * @bo: The buffer object. 308 * 309 * Returns a refcounted pointer to a buffer object. 310 */ 311 312static inline struct ttm_buffer_object * 313ttm_bo_reference(struct ttm_buffer_object *bo) 314{ 315 kref_get(&bo->kref); 316 return bo; 317} 318 319/** 320 * ttm_bo_wait - wait for buffer idle. 321 * 322 * @bo: The buffer object. 323 * @interruptible: Use interruptible wait. 324 * @no_wait: Return immediately if buffer is busy. 325 * 326 * This function must be called with the bo::mutex held, and makes 327 * sure any previous rendering to the buffer is completed. 328 * Note: It might be necessary to block validations before the 329 * wait by reserving the buffer. 330 * Returns -EBUSY if no_wait is true and the buffer is busy. 331 * Returns -ERESTARTSYS if interrupted by a signal. 332 */ 333extern int ttm_bo_wait(struct ttm_buffer_object *bo, bool lazy, 334 bool interruptible, bool no_wait); 335/** 336 * ttm_bo_validate 337 * 338 * @bo: The buffer object. 339 * @placement: Proposed placement for the buffer object. 340 * @interruptible: Sleep interruptible if sleeping. 341 * @no_wait_reserve: Return immediately if other buffers are busy. 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 */ 352extern int ttm_bo_validate(struct ttm_buffer_object *bo, 353 struct ttm_placement *placement, 354 bool interruptible, bool no_wait_reserve, 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 */ 364extern void ttm_bo_unref(struct ttm_buffer_object **bo); 365 366/** 367 * ttm_bo_lock_delayed_workqueue 368 * 369 * Prevent the delayed workqueue from running. 370 * Returns 371 * True if the workqueue was queued at the time 372 */ 373extern int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev); 374 375/** 376 * ttm_bo_unlock_delayed_workqueue 377 * 378 * Allows the delayed workqueue to run. 379 */ 380extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, 381 int resched); 382 383/** 384 * ttm_bo_synccpu_write_grab 385 * 386 * @bo: The buffer object: 387 * @no_wait: Return immediately if buffer is busy. 388 * 389 * Synchronizes a buffer object for CPU RW access. This means 390 * blocking command submission that affects the buffer and 391 * waiting for buffer idle. This lock is recursive. 392 * Returns 393 * -EBUSY if the buffer is busy and no_wait is true. 394 * -ERESTARTSYS if interrupted by a signal. 395 */ 396 397extern int 398ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait); 399/** 400 * ttm_bo_synccpu_write_release: 401 * 402 * @bo : The buffer object. 403 * 404 * Releases a synccpu lock. 405 */ 406extern void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo); 407 408/** 409 * ttm_bo_init 410 * 411 * @bdev: Pointer to a ttm_bo_device struct. 412 * @bo: Pointer to a ttm_buffer_object to be initialized. 413 * @size: Requested size of buffer object. 414 * @type: Requested type of buffer object. 415 * @flags: Initial placement flags. 416 * @page_alignment: Data alignment in pages. 417 * @buffer_start: Virtual address of user space data backing a 418 * user buffer object. 419 * @interruptible: If needing to sleep to wait for GPU resources, 420 * sleep interruptible. 421 * @persistant_swap_storage: Usually the swap storage is deleted for buffers 422 * pinned in physical memory. If this behaviour is not desired, this member 423 * holds a pointer to a persistant shmem object. Typically, this would 424 * point to the shmem object backing a GEM object if TTM is used to back a 425 * GEM user interface. 426 * @acc_size: Accounted size for this object. 427 * @destroy: Destroy function. Use NULL for kfree(). 428 * 429 * This function initializes a pre-allocated struct ttm_buffer_object. 430 * As this object may be part of a larger structure, this function, 431 * together with the @destroy function, 432 * enables driver-specific objects derived from a ttm_buffer_object. 433 * On successful return, the object kref and list_kref are set to 1. 434 * Returns 435 * -ENOMEM: Out of memory. 436 * -EINVAL: Invalid placement flags. 437 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 438 */ 439 440extern int ttm_bo_init(struct ttm_bo_device *bdev, 441 struct ttm_buffer_object *bo, 442 unsigned long size, 443 enum ttm_bo_type type, 444 struct ttm_placement *placement, 445 uint32_t page_alignment, 446 unsigned long buffer_start, 447 bool interrubtible, 448 struct file *persistant_swap_storage, 449 size_t acc_size, 450 void (*destroy) (struct ttm_buffer_object *)); 451/** 452 * ttm_bo_synccpu_object_init 453 * 454 * @bdev: Pointer to a ttm_bo_device struct. 455 * @bo: Pointer to a ttm_buffer_object to be initialized. 456 * @size: Requested size of buffer object. 457 * @type: Requested type of buffer object. 458 * @flags: Initial placement flags. 459 * @page_alignment: Data alignment in pages. 460 * @buffer_start: Virtual address of user space data backing a 461 * user buffer object. 462 * @interruptible: If needing to sleep while waiting for GPU resources, 463 * sleep interruptible. 464 * @persistant_swap_storage: Usually the swap storage is deleted for buffers 465 * pinned in physical memory. If this behaviour is not desired, this member 466 * holds a pointer to a persistant shmem object. Typically, this would 467 * point to the shmem object backing a GEM object if TTM is used to back a 468 * GEM user interface. 469 * @p_bo: On successful completion *p_bo points to the created object. 470 * 471 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init 472 * on that object. The destroy function is set to kfree(). 473 * Returns 474 * -ENOMEM: Out of memory. 475 * -EINVAL: Invalid placement flags. 476 * -ERESTARTSYS: Interrupted by signal while waiting for resources. 477 */ 478 479extern int ttm_bo_create(struct ttm_bo_device *bdev, 480 unsigned long size, 481 enum ttm_bo_type type, 482 struct ttm_placement *placement, 483 uint32_t page_alignment, 484 unsigned long buffer_start, 485 bool interruptible, 486 struct file *persistant_swap_storage, 487 struct ttm_buffer_object **p_bo); 488 489/** 490 * ttm_bo_check_placement 491 * 492 * @bo: the buffer object. 493 * @placement: placements 494 * 495 * Performs minimal validity checking on an intended change of 496 * placement flags. 497 * Returns 498 * -EINVAL: Intended change is invalid or not allowed. 499 */ 500extern int ttm_bo_check_placement(struct ttm_buffer_object *bo, 501 struct ttm_placement *placement); 502 503/** 504 * ttm_bo_init_mm 505 * 506 * @bdev: Pointer to a ttm_bo_device struct. 507 * @mem_type: The memory type. 508 * @p_size: size managed area in pages. 509 * 510 * Initialize a manager for a given memory type. 511 * Note: if part of driver firstopen, it must be protected from a 512 * potentially racing lastclose. 513 * Returns: 514 * -EINVAL: invalid size or memory type. 515 * -ENOMEM: Not enough memory. 516 * May also return driver-specified errors. 517 */ 518 519extern int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type, 520 unsigned long p_size); 521/** 522 * ttm_bo_clean_mm 523 * 524 * @bdev: Pointer to a ttm_bo_device struct. 525 * @mem_type: The memory type. 526 * 527 * Take down a manager for a given memory type after first walking 528 * the LRU list to evict any buffers left alive. 529 * 530 * Normally, this function is part of lastclose() or unload(), and at that 531 * point there shouldn't be any buffers left created by user-space, since 532 * there should've been removed by the file descriptor release() method. 533 * However, before this function is run, make sure to signal all sync objects, 534 * and verify that the delayed delete queue is empty. The driver must also 535 * make sure that there are no NO_EVICT buffers present in this memory type 536 * when the call is made. 537 * 538 * If this function is part of a VT switch, the caller must make sure that 539 * there are no appications currently validating buffers before this 540 * function is called. The caller can do that by first taking the 541 * struct ttm_bo_device::ttm_lock in write mode. 542 * 543 * Returns: 544 * -EINVAL: invalid or uninitialized memory type. 545 * -EBUSY: There are still buffers left in this memory type. 546 */ 547 548extern int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type); 549 550/** 551 * ttm_bo_evict_mm 552 * 553 * @bdev: Pointer to a ttm_bo_device struct. 554 * @mem_type: The memory type. 555 * 556 * Evicts all buffers on the lru list of the memory type. 557 * This is normally part of a VT switch or an 558 * out-of-memory-space-due-to-fragmentation handler. 559 * The caller must make sure that there are no other processes 560 * currently validating buffers, and can do that by taking the 561 * struct ttm_bo_device::ttm_lock in write mode. 562 * 563 * Returns: 564 * -EINVAL: Invalid or uninitialized memory type. 565 * -ERESTARTSYS: The call was interrupted by a signal while waiting to 566 * evict a buffer. 567 */ 568 569extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type); 570 571/** 572 * ttm_kmap_obj_virtual 573 * 574 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap. 575 * @is_iomem: Pointer to an integer that on return indicates 1 if the 576 * virtual map is io memory, 0 if normal memory. 577 * 578 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap. 579 * If *is_iomem is 1 on return, the virtual address points to an io memory area, 580 * that should strictly be accessed by the iowriteXX() and similar functions. 581 */ 582 583static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, 584 bool *is_iomem) 585{ 586 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK); 587 return map->virtual; 588} 589 590/** 591 * ttm_bo_kmap 592 * 593 * @bo: The buffer object. 594 * @start_page: The first page to map. 595 * @num_pages: Number of pages to map. 596 * @map: pointer to a struct ttm_bo_kmap_obj representing the map. 597 * 598 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the 599 * data in the buffer object. The ttm_kmap_obj_virtual function can then be 600 * used to obtain a virtual address to the data. 601 * 602 * Returns 603 * -ENOMEM: Out of memory. 604 * -EINVAL: Invalid range. 605 */ 606 607extern int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, 608 unsigned long num_pages, struct ttm_bo_kmap_obj *map); 609 610/** 611 * ttm_bo_kunmap 612 * 613 * @map: Object describing the map to unmap. 614 * 615 * Unmaps a kernel map set up by ttm_bo_kmap. 616 */ 617 618extern void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); 619 620 621/** 622 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object. 623 * 624 * @vma: vma as input from the fbdev mmap method. 625 * @bo: The bo backing the address space. The address space will 626 * have the same size as the bo, and start at offset 0. 627 * 628 * This function is intended to be called by the fbdev mmap method 629 * if the fbdev address space is to be backed by a bo. 630 */ 631 632extern int ttm_fbdev_mmap(struct vm_area_struct *vma, 633 struct ttm_buffer_object *bo); 634 635/** 636 * ttm_bo_mmap - mmap out of the ttm device address space. 637 * 638 * @filp: filp as input from the mmap method. 639 * @vma: vma as input from the mmap method. 640 * @bdev: Pointer to the ttm_bo_device with the address space manager. 641 * 642 * This function is intended to be called by the device mmap method. 643 * if the device address space is to be backed by the bo manager. 644 */ 645 646extern int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma, 647 struct ttm_bo_device *bdev); 648 649/** 650 * ttm_bo_io 651 * 652 * @bdev: Pointer to the struct ttm_bo_device. 653 * @filp: Pointer to the struct file attempting to read / write. 654 * @wbuf: User-space pointer to address of buffer to write. NULL on read. 655 * @rbuf: User-space pointer to address of buffer to read into. 656 * Null on write. 657 * @count: Number of bytes to read / write. 658 * @f_pos: Pointer to current file position. 659 * @write: 1 for read, 0 for write. 660 * 661 * This function implements read / write into ttm buffer objects, and is 662 * intended to 663 * be called from the fops::read and fops::write method. 664 * Returns: 665 * See man (2) write, man(2) read. In particular, 666 * the function may return -ERESTARTSYS if 667 * interrupted by a signal. 668 */ 669 670extern ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp, 671 const char __user *wbuf, char __user *rbuf, 672 size_t count, loff_t *f_pos, bool write); 673 674extern void ttm_bo_swapout_all(struct ttm_bo_device *bdev); 675 676#endif 677