1/************************************************************************** 2 * 3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 24 * USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27/* 28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> 29 */ 30 31#ifndef _TTM_BO_API_H_ 32#define _TTM_BO_API_H_ 33 34#include <drm/drm_gem.h> 35#include <drm/drm_hashtab.h> 36#include <drm/drm_vma_manager.h> 37#include <linux/kref.h> 38#include <linux/list.h> 39#include <linux/wait.h> 40#include <linux/mutex.h> 41#include <linux/mm.h> 42#include <linux/bitmap.h> 43#include <linux/dma-resv.h> 44 45#include "ttm_resource.h" 46 47struct ttm_global; 48 49struct ttm_device; 50 51struct dma_buf_map; 52 53struct drm_mm_node; 54 55struct ttm_placement; 56 57struct ttm_place; 58 59struct ttm_lru_bulk_move; 60 61/** 62 * enum ttm_bo_type 63 * 64 * @ttm_bo_type_device: These are 'normal' buffers that can 65 * be mmapped by user space. Each of these bos occupy a slot in the 66 * device address space, that can be used for normal vm operations. 67 * 68 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers, 69 * but they cannot be accessed from user-space. For kernel-only use. 70 * 71 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another 72 * driver. 73 */ 74 75enum ttm_bo_type { 76 ttm_bo_type_device, 77 ttm_bo_type_kernel, 78 ttm_bo_type_sg 79}; 80 81struct ttm_tt; 82 83/** 84 * struct ttm_buffer_object 85 * 86 * @base: drm_gem_object superclass data. 87 * @bdev: Pointer to the buffer object device structure. 88 * @type: The bo type. 89 * @page_alignment: Page alignment. 90 * @destroy: Destruction function. If NULL, kfree is used. 91 * @num_pages: Actual number of pages. 92 * @kref: Reference count of this buffer object. When this refcount reaches 93 * zero, the object is destroyed or put on the delayed delete list. 94 * @mem: structure describing current placement. 95 * @ttm: TTM structure holding system pages. 96 * @evicted: Whether the object was evicted without user-space knowing. 97 * @deleted: True if the object is only a zombie and already deleted. 98 * @lru: List head for the lru list. 99 * @ddestroy: List head for the delayed destroy list. 100 * @swap: List head for swap LRU list. 101 * @moving: Fence set when BO is moving 102 * @offset: The current GPU offset, which can have different meanings 103 * depending on the memory type. For SYSTEM type memory, it should be 0. 104 * @cur_placement: Hint of current placement. 105 * 106 * Base class for TTM buffer object, that deals with data placement and CPU 107 * mappings. GPU mappings are really up to the driver, but for simpler GPUs 108 * the driver can usually use the placement offset @offset directly as the 109 * GPU virtual address. For drivers implementing multiple 110 * GPU memory manager contexts, the driver should manage the address space 111 * in these contexts separately and use these objects to get the correct 112 * placement and caching for these GPU maps. This makes it possible to use 113 * these objects for even quite elaborate memory management schemes. 114 * The destroy member, the API visibility of this object makes it possible 115 * to derive driver specific types. 116 */ 117 118struct ttm_buffer_object { 119 struct drm_gem_object base; 120 121 /** 122 * Members constant at init. 123 */ 124 125 struct ttm_device *bdev; 126 enum ttm_bo_type type; 127 uint32_t page_alignment; 128 void (*destroy) (struct ttm_buffer_object *); 129 130 /** 131 * Members not needing protection. 132 */ 133 struct kref kref; 134 135 /** 136 * Members protected by the bo::resv::reserved lock. 137 */ 138 139 struct ttm_resource *resource; 140 struct ttm_tt *ttm; 141 bool deleted; 142 143 /** 144 * Members protected by the bdev::lru_lock. 145 */ 146 147 struct list_head lru; 148 struct list_head ddestroy; 149 150 /** 151 * Members protected by a bo reservation. 152 */ 153 154 struct dma_fence *moving; 155 unsigned priority; 156 unsigned pin_count; 157 158 /** 159 * Special members that are protected by the reserve lock 160 * and the bo::lock when written to. Can be read with 161 * either of these locks held. 162 */ 163 164 struct sg_table *sg; 165}; 166 167/** 168 * struct ttm_bo_kmap_obj 169 * 170 * @virtual: The current kernel virtual address. 171 * @page: The page when kmap'ing a single page. 172 * @bo_kmap_type: Type of bo_kmap. 173 * 174 * Object describing a kernel mapping. Since a TTM bo may be located 175 * in various memory types with various caching policies, the 176 * mapping can either be an ioremap, a vmap, a kmap or part of a 177 * premapped region. 178 */ 179 180#define TTM_BO_MAP_IOMEM_MASK 0x80 181struct ttm_bo_kmap_obj { 182 void *virtual; 183 struct page *page; 184 enum { 185 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK, 186 ttm_bo_map_vmap = 2, 187 ttm_bo_map_kmap = 3, 188 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK, 189 } bo_kmap_type; 190 struct ttm_buffer_object *bo; 191}; 192 193/** 194 * struct ttm_operation_ctx 195 * 196 * @interruptible: Sleep interruptible if sleeping. 197 * @no_wait_gpu: Return immediately if the GPU is busy. 198 * @gfp_retry_mayfail: Set the __GFP_RETRY_MAYFAIL when allocation pages. 199 * @allow_res_evict: Allow eviction of reserved BOs. Can be used when multiple 200 * BOs share the same reservation object. 201 * @force_alloc: Don't check the memory account during suspend or CPU page 202 * faults. Should only be used by TTM internally. 203 * @resv: Reservation object to allow reserved evictions with. 204 * 205 * Context for TTM operations like changing buffer placement or general memory 206 * allocation. 207 */ 208struct ttm_operation_ctx { 209 bool interruptible; 210 bool no_wait_gpu; 211 bool gfp_retry_mayfail; 212 bool allow_res_evict; 213 bool force_alloc; 214 struct dma_resv *resv; 215 uint64_t bytes_moved; 216}; 217 218/** 219 * ttm_bo_get - reference a struct ttm_buffer_object 220 * 221 * @bo: The buffer object. 222 */ 223static inline void ttm_bo_get(struct ttm_buffer_object *bo) 224{ 225 kref_get(&bo->kref); 226} 227 228/** 229 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless 230 * its refcount has already reached zero. 231 * @bo: The buffer object. 232 * 233 * Used to reference a TTM buffer object in lookups where the object is removed 234 * from the lookup structure during the destructor and for RCU lookups. 235 * 236 * Returns: @bo if the referencing was successful, NULL otherwise. 237 */ 238static inline __must_check struct ttm_buffer_object * 239ttm_bo_get_unless_zero(struct ttm_buffer_object *bo) 240{ 241 if (!kref_get_unless_zero(&bo->kref)) 242 return NULL; 243 return bo; 244} 245 246/** 247 * ttm_bo_wait - wait for buffer idle. 248 * 249 * @bo: The buffer object. 250 * @interruptible: Use interruptible wait. 251 * @no_wait: Return immediately if buffer is busy. 252 * 253 * This function must be called with the bo::mutex held, and makes 254 * sure any previous rendering to the buffer is completed. 255 * Note: It might be necessary to block validations before the 256 * wait by reserving the buffer. 257 * Returns -EBUSY if no_wait is true and the buffer is busy. 258 * Returns -ERESTARTSYS if interrupted by a signal. 259 */ 260int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait); 261 262static inline int ttm_bo_wait_ctx(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx) 263{ 264 return ttm_bo_wait(bo, ctx->interruptible, ctx->no_wait_gpu); 265} 266 267/** 268 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo 269 * 270 * @placement: Return immediately if buffer is busy. 271 * @mem: The struct ttm_resource indicating the region where the bo resides 272 * @new_flags: Describes compatible placement found 273 * 274 * Returns true if the placement is compatible 275 */ 276bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_resource *mem, 277 uint32_t *new_flags); 278 279/** 280 * ttm_bo_validate 281 * 282 * @bo: The buffer object. 283 * @placement: Proposed placement for the buffer object. 284 * @ctx: validation parameters. 285 * 286 * Changes placement and caching policy of the buffer object 287 * according proposed placement. 288 * Returns 289 * -EINVAL on invalid proposed placement. 290 * -ENOMEM on out-of-memory condition. 291 * -EBUSY if no_wait is true and buffer busy. 292 * -ERESTARTSYS if interrupted by a signal. 293 */ 294int ttm_bo_validate(struct ttm_buffer_object *bo, 295 struct ttm_placement *placement, 296 struct ttm_operation_ctx *ctx); 297 298/** 299 * ttm_bo_put 300 * 301 * @bo: The buffer object. 302 * 303 * Unreference a buffer object. 304 */ 305void ttm_bo_put(struct ttm_buffer_object *bo); 306 307/** 308 * ttm_bo_move_to_lru_tail 309 * 310 * @bo: The buffer object. 311 * @mem: Resource object. 312 * @bulk: optional bulk move structure to remember BO positions 313 * 314 * Move this BO to the tail of all lru lists used to lookup and reserve an 315 * object. This function must be called with struct ttm_global::lru_lock 316 * held, and is used to make a BO less likely to be considered for eviction. 317 */ 318void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo, 319 struct ttm_resource *mem, 320 struct ttm_lru_bulk_move *bulk); 321 322/** 323 * ttm_bo_bulk_move_lru_tail 324 * 325 * @bulk: bulk move structure 326 * 327 * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that 328 * BO order never changes. Should be called with ttm_global::lru_lock held. 329 */ 330void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk); 331 332/** 333 * ttm_bo_lock_delayed_workqueue 334 * 335 * Prevent the delayed workqueue from running. 336 * Returns 337 * True if the workqueue was queued at the time 338 */ 339int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev); 340 341/** 342 * ttm_bo_unlock_delayed_workqueue 343 * 344 * Allows the delayed workqueue to run. 345 */ 346void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched); 347 348/** 349 * ttm_bo_eviction_valuable 350 * 351 * @bo: The buffer object to evict 352 * @place: the placement we need to make room for 353 * 354 * Check if it is valuable to evict the BO to make room for the given placement. 355 */ 356bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo, 357 const struct ttm_place *place); 358 359/** 360 * ttm_bo_init_reserved 361 * 362 * @bdev: Pointer to a ttm_device struct. 363 * @bo: Pointer to a ttm_buffer_object to be initialized. 364 * @size: Requested size of buffer object. 365 * @type: Requested type of buffer object. 366 * @flags: Initial placement flags. 367 * @page_alignment: Data alignment in pages. 368 * @ctx: TTM operation context for memory allocation. 369 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one. 370 * @destroy: Destroy function. Use NULL for kfree(). 371 * 372 * This function initializes a pre-allocated struct ttm_buffer_object. 373 * As this object may be part of a larger structure, this function, 374 * together with the @destroy function, 375 * enables driver-specific objects derived from a ttm_buffer_object. 376 * 377 * On successful return, the caller owns an object kref to @bo. The kref and 378 * list_kref are usually set to 1, but note that in some situations, other 379 * tasks may already be holding references to @bo as well. 380 * Furthermore, if resv == NULL, the buffer's reservation lock will be held, 381 * and it is the caller's responsibility to call ttm_bo_unreserve. 382 * 383 * If a failure occurs, the function will call the @destroy function, or 384 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is 385 * illegal and will likely cause memory corruption. 386 * 387 * Returns 388 * -ENOMEM: Out of memory. 389 * -EINVAL: Invalid placement flags. 390 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 391 */ 392 393int ttm_bo_init_reserved(struct ttm_device *bdev, 394 struct ttm_buffer_object *bo, 395 size_t size, enum ttm_bo_type type, 396 struct ttm_placement *placement, 397 uint32_t page_alignment, 398 struct ttm_operation_ctx *ctx, 399 struct sg_table *sg, struct dma_resv *resv, 400 void (*destroy) (struct ttm_buffer_object *)); 401 402/** 403 * ttm_bo_init 404 * 405 * @bdev: Pointer to a ttm_device struct. 406 * @bo: Pointer to a ttm_buffer_object to be initialized. 407 * @size: Requested size of buffer object. 408 * @type: Requested type of buffer object. 409 * @flags: Initial placement flags. 410 * @page_alignment: Data alignment in pages. 411 * @interruptible: If needing to sleep to wait for GPU resources, 412 * sleep interruptible. 413 * pinned in physical memory. If this behaviour is not desired, this member 414 * holds a pointer to a persistent shmem object. Typically, this would 415 * point to the shmem object backing a GEM object if TTM is used to back a 416 * GEM user interface. 417 * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one. 418 * @destroy: Destroy function. Use NULL for kfree(). 419 * 420 * This function initializes a pre-allocated struct ttm_buffer_object. 421 * As this object may be part of a larger structure, this function, 422 * together with the @destroy function, 423 * enables driver-specific objects derived from a ttm_buffer_object. 424 * 425 * On successful return, the caller owns an object kref to @bo. The kref and 426 * list_kref are usually set to 1, but note that in some situations, other 427 * tasks may already be holding references to @bo as well. 428 * 429 * If a failure occurs, the function will call the @destroy function, or 430 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is 431 * illegal and will likely cause memory corruption. 432 * 433 * Returns 434 * -ENOMEM: Out of memory. 435 * -EINVAL: Invalid placement flags. 436 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources. 437 */ 438int ttm_bo_init(struct ttm_device *bdev, struct ttm_buffer_object *bo, 439 size_t size, enum ttm_bo_type type, 440 struct ttm_placement *placement, 441 uint32_t page_alignment, bool interrubtible, 442 struct sg_table *sg, struct dma_resv *resv, 443 void (*destroy) (struct ttm_buffer_object *)); 444 445/** 446 * ttm_kmap_obj_virtual 447 * 448 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap. 449 * @is_iomem: Pointer to an integer that on return indicates 1 if the 450 * virtual map is io memory, 0 if normal memory. 451 * 452 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap. 453 * If *is_iomem is 1 on return, the virtual address points to an io memory area, 454 * that should strictly be accessed by the iowriteXX() and similar functions. 455 */ 456static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map, 457 bool *is_iomem) 458{ 459 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK); 460 return map->virtual; 461} 462 463/** 464 * ttm_bo_kmap 465 * 466 * @bo: The buffer object. 467 * @start_page: The first page to map. 468 * @num_pages: Number of pages to map. 469 * @map: pointer to a struct ttm_bo_kmap_obj representing the map. 470 * 471 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the 472 * data in the buffer object. The ttm_kmap_obj_virtual function can then be 473 * used to obtain a virtual address to the data. 474 * 475 * Returns 476 * -ENOMEM: Out of memory. 477 * -EINVAL: Invalid range. 478 */ 479int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page, 480 unsigned long num_pages, struct ttm_bo_kmap_obj *map); 481 482/** 483 * ttm_bo_kunmap 484 * 485 * @map: Object describing the map to unmap. 486 * 487 * Unmaps a kernel map set up by ttm_bo_kmap. 488 */ 489void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); 490 491/** 492 * ttm_bo_vmap 493 * 494 * @bo: The buffer object. 495 * @map: pointer to a struct dma_buf_map representing the map. 496 * 497 * Sets up a kernel virtual mapping, using ioremap or vmap to the 498 * data in the buffer object. The parameter @map returns the virtual 499 * address as struct dma_buf_map. Unmap the buffer with ttm_bo_vunmap(). 500 * 501 * Returns 502 * -ENOMEM: Out of memory. 503 * -EINVAL: Invalid range. 504 */ 505int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map); 506 507/** 508 * ttm_bo_vunmap 509 * 510 * @bo: The buffer object. 511 * @map: Object describing the map to unmap. 512 * 513 * Unmaps a kernel map set up by ttm_bo_vmap(). 514 */ 515void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map *map); 516 517/** 518 * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object. 519 * 520 * @vma: vma as input from the fbdev mmap method. 521 * @bo: The bo backing the address space. 522 * 523 * Maps a buffer object. 524 */ 525int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo); 526 527/** 528 * ttm_bo_io 529 * 530 * @bdev: Pointer to the struct ttm_device. 531 * @filp: Pointer to the struct file attempting to read / write. 532 * @wbuf: User-space pointer to address of buffer to write. NULL on read. 533 * @rbuf: User-space pointer to address of buffer to read into. 534 * Null on write. 535 * @count: Number of bytes to read / write. 536 * @f_pos: Pointer to current file position. 537 * @write: 1 for read, 0 for write. 538 * 539 * This function implements read / write into ttm buffer objects, and is 540 * intended to 541 * be called from the fops::read and fops::write method. 542 * Returns: 543 * See man (2) write, man(2) read. In particular, 544 * the function may return -ERESTARTSYS if 545 * interrupted by a signal. 546 */ 547ssize_t ttm_bo_io(struct ttm_device *bdev, struct file *filp, 548 const char __user *wbuf, char __user *rbuf, 549 size_t count, loff_t *f_pos, bool write); 550 551int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, 552 gfp_t gfp_flags); 553 554/** 555 * ttm_bo_pin - Pin the buffer object. 556 * @bo: The buffer object to pin 557 * 558 * Make sure the buffer is not evicted any more during memory pressure. 559 */ 560static inline void ttm_bo_pin(struct ttm_buffer_object *bo) 561{ 562 dma_resv_assert_held(bo->base.resv); 563 WARN_ON_ONCE(!kref_read(&bo->kref)); 564 ++bo->pin_count; 565} 566 567/** 568 * ttm_bo_unpin - Unpin the buffer object. 569 * @bo: The buffer object to unpin 570 * 571 * Allows the buffer object to be evicted again during memory pressure. 572 */ 573static inline void ttm_bo_unpin(struct ttm_buffer_object *bo) 574{ 575 dma_resv_assert_held(bo->base.resv); 576 WARN_ON_ONCE(!kref_read(&bo->kref)); 577 if (bo->pin_count) 578 --bo->pin_count; 579 else 580 WARN_ON_ONCE(true); 581} 582 583int ttm_mem_evict_first(struct ttm_device *bdev, 584 struct ttm_resource_manager *man, 585 const struct ttm_place *place, 586 struct ttm_operation_ctx *ctx, 587 struct ww_acquire_ctx *ticket); 588 589/* Default number of pre-faulted pages in the TTM fault handler */ 590#define TTM_BO_VM_NUM_PREFAULT 16 591 592vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo, 593 struct vm_fault *vmf); 594 595vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf, 596 pgprot_t prot, 597 pgoff_t num_prefault, 598 pgoff_t fault_page_size); 599 600vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf); 601 602void ttm_bo_vm_open(struct vm_area_struct *vma); 603 604void ttm_bo_vm_close(struct vm_area_struct *vma); 605 606int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, 607 void *buf, int len, int write); 608bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all); 609 610vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot); 611 612#endif 613