1 /* SPDX-License-Identifier: MIT */ 2 /* 3 * Copyright © 2021 Intel Corporation 4 */ 5 6 #ifndef _XE_BO_H_ 7 #define _XE_BO_H_ 8 9 #include <drm/ttm/ttm_tt.h> 10 11 #include "xe_bo_types.h" 12 #include "xe_ggtt.h" 13 #include "xe_macros.h" 14 #include "xe_validation.h" 15 #include "xe_vm_types.h" 16 #include "xe_vm.h" 17 #include "xe_vram_types.h" 18 19 #define XE_DEFAULT_GTT_SIZE_MB 3072ULL /* 3GB by default */ 20 21 #define XE_BO_FLAG_USER BIT(0) 22 /* The bits below need to be contiguous, or things break */ 23 #define XE_BO_FLAG_SYSTEM BIT(1) 24 #define XE_BO_FLAG_VRAM0 BIT(2) 25 #define XE_BO_FLAG_VRAM1 BIT(3) 26 #define XE_BO_FLAG_VRAM_MASK (XE_BO_FLAG_VRAM0 | XE_BO_FLAG_VRAM1) 27 /* -- */ 28 #define XE_BO_FLAG_STOLEN BIT(4) 29 #define XE_BO_FLAG_VRAM(vram) (XE_BO_FLAG_VRAM0 << ((vram)->id)) 30 #define XE_BO_FLAG_VRAM_IF_DGFX(tile) (IS_DGFX(tile_to_xe(tile)) ? \ 31 XE_BO_FLAG_VRAM((tile)->mem.vram) : \ 32 XE_BO_FLAG_SYSTEM) 33 #define XE_BO_FLAG_GGTT BIT(5) 34 #define XE_BO_FLAG_IGNORE_MIN_PAGE_SIZE BIT(6) 35 #define XE_BO_FLAG_PINNED BIT(7) 36 #define XE_BO_FLAG_NO_RESV_EVICT BIT(8) 37 #define XE_BO_FLAG_DEFER_BACKING BIT(9) 38 #define XE_BO_FLAG_FORCE_WC BIT(10) 39 #define XE_BO_FLAG_FIXED_PLACEMENT BIT(11) 40 #define XE_BO_FLAG_PAGETABLE BIT(12) 41 #define XE_BO_FLAG_NEEDS_CPU_ACCESS BIT(13) 42 #define XE_BO_FLAG_NEEDS_UC BIT(14) 43 #define XE_BO_FLAG_NEEDS_64K BIT(15) 44 #define XE_BO_FLAG_NEEDS_2M BIT(16) 45 #define XE_BO_FLAG_GGTT_INVALIDATE BIT(17) 46 #define XE_BO_FLAG_PINNED_NORESTORE BIT(18) 47 #define XE_BO_FLAG_PINNED_LATE_RESTORE BIT(19) 48 #define XE_BO_FLAG_GGTT0 BIT(20) 49 #define XE_BO_FLAG_GGTT1 BIT(21) 50 #define XE_BO_FLAG_GGTT2 BIT(22) 51 #define XE_BO_FLAG_GGTT3 BIT(23) 52 #define XE_BO_FLAG_CPU_ADDR_MIRROR BIT(24) 53 #define XE_BO_FLAG_FORCE_USER_VRAM BIT(25) 54 #define XE_BO_FLAG_NO_COMPRESSION BIT(26) 55 56 /* this one is trigger internally only */ 57 #define XE_BO_FLAG_INTERNAL_TEST BIT(30) 58 #define XE_BO_FLAG_INTERNAL_64K BIT(31) 59 60 #define XE_BO_FLAG_GGTT_ALL (XE_BO_FLAG_GGTT0 | \ 61 XE_BO_FLAG_GGTT1 | \ 62 XE_BO_FLAG_GGTT2 | \ 63 XE_BO_FLAG_GGTT3) 64 65 #define XE_BO_FLAG_GGTTx(tile) \ 66 (XE_BO_FLAG_GGTT0 << (tile)->id) 67 68 #define XE_PTE_SHIFT 12 69 #define XE_PAGE_SIZE (1 << XE_PTE_SHIFT) 70 #define XE_PTE_MASK (XE_PAGE_SIZE - 1) 71 #define XE_PDE_SHIFT (XE_PTE_SHIFT - 3) 72 #define XE_PDES (1 << XE_PDE_SHIFT) 73 #define XE_PDE_MASK (XE_PDES - 1) 74 75 #define XE_64K_PTE_SHIFT 16 76 #define XE_64K_PAGE_SIZE (1 << XE_64K_PTE_SHIFT) 77 #define XE_64K_PTE_MASK (XE_64K_PAGE_SIZE - 1) 78 #define XE_64K_PDE_MASK (XE_PDE_MASK >> 4) 79 80 #define XE_PL_SYSTEM TTM_PL_SYSTEM 81 #define XE_PL_TT TTM_PL_TT 82 #define XE_PL_VRAM0 TTM_PL_VRAM 83 #define XE_PL_VRAM1 (XE_PL_VRAM0 + 1) 84 #define XE_PL_STOLEN (TTM_NUM_MEM_TYPES - 1) 85 86 #define XE_BO_PROPS_INVALID (-1) 87 88 #define XE_PCI_BARRIER_MMAP_OFFSET (0x50 << XE_PTE_SHIFT) 89 90 /** 91 * enum xe_madv_purgeable_state - Buffer object purgeable state enumeration 92 * 93 * This enum defines the possible purgeable states for a buffer object, 94 * allowing userspace to provide memory usage hints to the kernel for 95 * better memory management under pressure. 96 * 97 * @XE_MADV_PURGEABLE_WILLNEED: The buffer object is needed and should not be purged. 98 * This is the default state. 99 * @XE_MADV_PURGEABLE_DONTNEED: The buffer object is not currently needed and can be 100 * purged by the kernel under memory pressure. 101 * @XE_MADV_PURGEABLE_PURGED: The buffer object has been purged by the kernel. 102 * 103 * Accessing a purged buffer will result in an error. Per i915 semantics, 104 * once purged, a BO remains permanently invalid and must be destroyed and recreated. 105 */ 106 enum xe_madv_purgeable_state { 107 XE_MADV_PURGEABLE_WILLNEED, 108 XE_MADV_PURGEABLE_DONTNEED, 109 XE_MADV_PURGEABLE_PURGED, 110 }; 111 112 struct sg_table; 113 114 struct xe_bo *xe_bo_alloc(void); 115 void xe_bo_free(struct xe_bo *bo); 116 117 struct xe_bo *xe_bo_init_locked(struct xe_device *xe, struct xe_bo *bo, 118 struct xe_tile *tile, struct dma_resv *resv, 119 struct ttm_lru_bulk_move *bulk, size_t size, 120 u16 cpu_caching, enum ttm_bo_type type, 121 u32 flags, struct dma_buf *dma_buf, 122 struct drm_exec *exec); 123 struct xe_bo *xe_bo_create_locked(struct xe_device *xe, struct xe_tile *tile, 124 struct xe_vm *vm, size_t size, 125 enum ttm_bo_type type, u32 flags, 126 struct drm_exec *exec); 127 struct xe_bo *xe_bo_create_user(struct xe_device *xe, struct xe_vm *vm, size_t size, 128 u16 cpu_caching, u32 flags, struct drm_exec *exec); 129 struct xe_bo *xe_bo_create_pin_map(struct xe_device *xe, struct xe_tile *tile, 130 struct xe_vm *vm, size_t size, 131 enum ttm_bo_type type, u32 flags, 132 struct drm_exec *exec); 133 struct xe_bo *xe_bo_create_pin_map_novm(struct xe_device *xe, struct xe_tile *tile, 134 size_t size, enum ttm_bo_type type, u32 flags, 135 bool intr); 136 struct xe_bo *xe_bo_create_pin_range_novm(struct xe_device *xe, struct xe_tile *tile, 137 size_t size, u64 start, u64 end, 138 enum ttm_bo_type type, u32 flags); 139 struct xe_bo * 140 xe_bo_create_pin_map_at_novm(struct xe_device *xe, struct xe_tile *tile, 141 size_t size, u64 offset, enum ttm_bo_type type, 142 u32 flags, u64 alignment, bool intr); 143 struct xe_bo *xe_managed_bo_create_pin_map(struct xe_device *xe, struct xe_tile *tile, 144 size_t size, u32 flags); 145 void xe_managed_bo_unpin_map_no_vm(struct xe_bo *bo); 146 struct xe_bo *xe_managed_bo_create_from_data(struct xe_device *xe, struct xe_tile *tile, 147 const void *data, size_t size, u32 flags); 148 int xe_managed_bo_reinit_in_vram(struct xe_device *xe, struct xe_tile *tile, struct xe_bo **src); 149 150 int xe_bo_placement_for_flags(struct xe_device *xe, struct xe_bo *bo, 151 u32 bo_flags, enum ttm_bo_type type); 152 153 static inline struct xe_bo *ttm_to_xe_bo(const struct ttm_buffer_object *bo) 154 { 155 return container_of(bo, struct xe_bo, ttm); 156 } 157 158 static inline struct xe_bo *gem_to_xe_bo(const struct drm_gem_object *obj) 159 { 160 return container_of(obj, struct xe_bo, ttm.base); 161 } 162 163 #define xe_bo_device(bo) ttm_to_xe_device((bo)->ttm.bdev) 164 165 static inline struct xe_bo *xe_bo_get(struct xe_bo *bo) 166 { 167 if (bo) 168 drm_gem_object_get(&bo->ttm.base); 169 170 return bo; 171 } 172 173 void xe_bo_put(struct xe_bo *bo); 174 175 /* 176 * xe_bo_get_unless_zero() - Conditionally obtain a GEM object refcount on an 177 * xe bo 178 * @bo: The bo for which we want to obtain a refcount. 179 * 180 * There is a short window between where the bo's GEM object refcount reaches 181 * zero and where we put the final ttm_bo reference. Code in the eviction- and 182 * shrinking path should therefore attempt to grab a gem object reference before 183 * trying to use members outside of the base class ttm object. This function is 184 * intended for that purpose. On successful return, this function must be paired 185 * with an xe_bo_put(). 186 * 187 * Return: @bo on success, NULL on failure. 188 */ 189 static inline __must_check struct xe_bo *xe_bo_get_unless_zero(struct xe_bo *bo) 190 { 191 if (!bo || !kref_get_unless_zero(&bo->ttm.base.refcount)) 192 return NULL; 193 194 return bo; 195 } 196 197 static inline void __xe_bo_unset_bulk_move(struct xe_bo *bo) 198 { 199 if (bo) 200 ttm_bo_set_bulk_move(&bo->ttm, NULL); 201 } 202 203 static inline void xe_bo_assert_held(struct xe_bo *bo) 204 { 205 if (bo) 206 dma_resv_assert_held((bo)->ttm.base.resv); 207 } 208 209 int xe_bo_lock(struct xe_bo *bo, bool intr); 210 211 void xe_bo_unlock(struct xe_bo *bo); 212 213 static inline void xe_bo_unlock_vm_held(struct xe_bo *bo) 214 { 215 if (bo) { 216 XE_WARN_ON(bo->vm && bo->ttm.base.resv != xe_vm_resv(bo->vm)); 217 if (bo->vm) 218 xe_vm_assert_held(bo->vm); 219 else 220 dma_resv_unlock(bo->ttm.base.resv); 221 } 222 } 223 224 int xe_bo_pin_external(struct xe_bo *bo, bool in_place, struct drm_exec *exec); 225 int xe_bo_pin(struct xe_bo *bo, struct drm_exec *exec); 226 void xe_bo_unpin_external(struct xe_bo *bo); 227 void xe_bo_unpin(struct xe_bo *bo); 228 int xe_bo_validate(struct xe_bo *bo, struct xe_vm *vm, bool allow_res_evict, 229 struct drm_exec *exec); 230 231 static inline bool xe_bo_is_pinned(struct xe_bo *bo) 232 { 233 return bo->ttm.pin_count; 234 } 235 236 static inline bool xe_bo_is_protected(const struct xe_bo *bo) 237 { 238 return bo->pxp_key_instance; 239 } 240 241 /** 242 * xe_bo_is_purged() - Check if buffer object has been purged 243 * @bo: The buffer object to check 244 * 245 * Checks if the buffer object's backing store has been discarded by the 246 * kernel due to memory pressure after being marked as purgeable (DONTNEED). 247 * Once purged, the BO cannot be restored and any attempt to use it will fail. 248 * 249 * Context: Caller must hold the BO's dma-resv lock 250 * Return: true if the BO has been purged, false otherwise 251 */ 252 static inline bool xe_bo_is_purged(struct xe_bo *bo) 253 { 254 xe_bo_assert_held(bo); 255 return bo->purgeable.state == XE_MADV_PURGEABLE_PURGED; 256 } 257 258 /** 259 * xe_bo_madv_is_dontneed() - Check if BO is marked as DONTNEED 260 * @bo: The buffer object to check 261 * 262 * Checks if userspace has marked this BO as DONTNEED (i.e., its contents 263 * are not currently needed and can be discarded under memory pressure). 264 * This is used internally to decide whether a BO is eligible for purging. 265 * 266 * Context: Caller must hold the BO's dma-resv lock 267 * Return: true if the BO is marked DONTNEED, false otherwise 268 */ 269 static inline bool xe_bo_madv_is_dontneed(struct xe_bo *bo) 270 { 271 xe_bo_assert_held(bo); 272 return bo->purgeable.state == XE_MADV_PURGEABLE_DONTNEED; 273 } 274 275 void xe_bo_set_purgeable_state(struct xe_bo *bo, enum xe_madv_purgeable_state new_state); 276 277 /** 278 * xe_bo_willneed_get_locked() - Acquire a WILLNEED holder on a BO 279 * @bo: Buffer object 280 * 281 * Increments willneed_count and, on a 0->1 transition, promotes the BO 282 * from DONTNEED to WILLNEED. PURGED is terminal and is never modified. 283 * 284 * Caller must hold the BO's dma-resv lock. 285 */ 286 static inline void xe_bo_willneed_get_locked(struct xe_bo *bo) 287 { 288 xe_bo_assert_held(bo); 289 290 /* Imported BOs are owned externally; do not track purgeability. */ 291 if (drm_gem_is_imported(&bo->ttm.base)) 292 return; 293 294 if (bo->purgeable.willneed_count++ == 0 && xe_bo_madv_is_dontneed(bo)) 295 xe_bo_set_purgeable_state(bo, XE_MADV_PURGEABLE_WILLNEED); 296 } 297 298 /** 299 * xe_bo_willneed_put_locked() - Release a WILLNEED holder on a BO 300 * @bo: Buffer object 301 * 302 * Decrements willneed_count and, on a 1->0 transition, marks the BO 303 * DONTNEED only if it still has VMAs (implying all active VMAs are 304 * DONTNEED). If the last VMA is being removed, preserve the current BO 305 * state to match the previous VMA-walk semantics. 306 * 307 * PURGED is terminal and the BO state is never modified. 308 * 309 * Caller must hold the BO's dma-resv lock. 310 */ 311 static inline void xe_bo_willneed_put_locked(struct xe_bo *bo) 312 { 313 xe_bo_assert_held(bo); 314 315 if (drm_gem_is_imported(&bo->ttm.base)) 316 return; 317 318 xe_assert(xe_bo_device(bo), bo->purgeable.willneed_count > 0); 319 if (--bo->purgeable.willneed_count == 0 && bo->purgeable.vma_count > 0 && 320 !xe_bo_is_purged(bo)) 321 xe_bo_set_purgeable_state(bo, XE_MADV_PURGEABLE_DONTNEED); 322 } 323 324 /** 325 * xe_bo_vma_count_inc_locked() - Account a new VMA on a BO 326 * @bo: Buffer object 327 * 328 * Increments vma_count. 329 * 330 * Caller must hold the BO's dma-resv lock. 331 */ 332 static inline void xe_bo_vma_count_inc_locked(struct xe_bo *bo) 333 { 334 xe_bo_assert_held(bo); 335 336 if (drm_gem_is_imported(&bo->ttm.base)) 337 return; 338 339 bo->purgeable.vma_count++; 340 } 341 342 /** 343 * xe_bo_vma_count_dec_locked() - Account a VMA removal on a BO 344 * @bo: Buffer object 345 * 346 * Decrements vma_count. 347 * 348 * Caller must hold the BO's dma-resv lock. 349 */ 350 static inline void xe_bo_vma_count_dec_locked(struct xe_bo *bo) 351 { 352 xe_bo_assert_held(bo); 353 354 if (drm_gem_is_imported(&bo->ttm.base)) 355 return; 356 357 xe_assert(xe_bo_device(bo), bo->purgeable.vma_count > 0); 358 bo->purgeable.vma_count--; 359 } 360 361 static inline void xe_bo_unpin_map_no_vm(struct xe_bo *bo) 362 { 363 if (likely(bo)) { 364 xe_bo_lock(bo, false); 365 xe_bo_unpin(bo); 366 xe_bo_unlock(bo); 367 368 xe_bo_put(bo); 369 } 370 } 371 372 bool xe_bo_is_xe_bo(struct ttm_buffer_object *bo); 373 dma_addr_t __xe_bo_addr(struct xe_bo *bo, u64 offset, size_t page_size); 374 dma_addr_t xe_bo_addr(struct xe_bo *bo, u64 offset, size_t page_size); 375 376 static inline dma_addr_t 377 xe_bo_main_addr(struct xe_bo *bo, size_t page_size) 378 { 379 return xe_bo_addr(bo, 0, page_size); 380 } 381 382 /** 383 * xe_bo_size() - Xe BO size 384 * @bo: The bo object. 385 * 386 * Simple helper to return Xe BO's size. 387 * 388 * Return: Xe BO's size 389 */ 390 static inline size_t xe_bo_size(struct xe_bo *bo) 391 { 392 return bo->ttm.base.size; 393 } 394 395 static inline u32 396 __xe_bo_ggtt_addr(struct xe_bo *bo, u8 tile_id) 397 { 398 struct xe_ggtt_node *ggtt_node = bo->ggtt_node[tile_id]; 399 u64 offset; 400 401 if (XE_WARN_ON(!ggtt_node)) 402 return 0; 403 404 offset = xe_ggtt_node_addr(ggtt_node); 405 XE_WARN_ON(offset + xe_bo_size(bo) > (1ull << 32)); 406 return offset; 407 } 408 409 static inline u32 410 xe_bo_ggtt_addr(struct xe_bo *bo) 411 { 412 xe_assert(xe_bo_device(bo), bo->tile); 413 414 return __xe_bo_ggtt_addr(bo, bo->tile->id); 415 } 416 417 int xe_bo_vmap(struct xe_bo *bo); 418 void xe_bo_vunmap(struct xe_bo *bo); 419 int xe_bo_read(struct xe_bo *bo, u64 offset, void *dst, int size); 420 421 bool mem_type_is_vram(u32 mem_type); 422 bool xe_bo_is_vram(struct xe_bo *bo); 423 bool xe_bo_is_visible_vram(struct xe_bo *bo); 424 bool xe_bo_is_stolen(struct xe_bo *bo); 425 bool xe_bo_is_stolen_devmem(struct xe_bo *bo); 426 bool xe_bo_is_vm_bound(struct xe_bo *bo); 427 bool xe_bo_has_single_placement(struct xe_bo *bo); 428 uint64_t vram_region_gpu_offset(struct ttm_resource *res); 429 430 bool xe_bo_can_migrate(struct xe_bo *bo, u32 mem_type); 431 432 int xe_bo_migrate(struct xe_bo *bo, u32 mem_type, struct ttm_operation_ctx *ctc, 433 struct drm_exec *exec); 434 int xe_bo_evict(struct xe_bo *bo, struct drm_exec *exec); 435 436 int xe_bo_evict_pinned(struct xe_bo *bo); 437 int xe_bo_notifier_prepare_pinned(struct xe_bo *bo); 438 int xe_bo_notifier_unprepare_pinned(struct xe_bo *bo); 439 int xe_bo_restore_pinned(struct xe_bo *bo); 440 441 int xe_bo_dma_unmap_pinned(struct xe_bo *bo); 442 443 extern const struct ttm_device_funcs xe_ttm_funcs; 444 extern const char *const xe_mem_type_to_name[]; 445 446 int xe_gem_create_ioctl(struct drm_device *dev, void *data, 447 struct drm_file *file); 448 int xe_gem_mmap_offset_ioctl(struct drm_device *dev, void *data, 449 struct drm_file *file); 450 void xe_bo_runtime_pm_release_mmap_offset(struct xe_bo *bo); 451 452 int xe_bo_dumb_create(struct drm_file *file_priv, 453 struct drm_device *dev, 454 struct drm_mode_create_dumb *args); 455 456 bool xe_bo_needs_ccs_pages(struct xe_bo *bo); 457 458 int xe_bo_decompress(struct xe_bo *bo); 459 460 static inline size_t xe_bo_ccs_pages_start(struct xe_bo *bo) 461 { 462 return PAGE_ALIGN(xe_bo_size(bo)); 463 } 464 465 /** 466 * xe_bo_has_valid_ccs_bb - Check if CCS's BBs were setup for the BO. 467 * @bo: the &xe_bo to check 468 * 469 * The CCS's BBs should only be setup by the driver VF, but it is safe 470 * to call this function also by non-VF driver. 471 * 472 * Return: true iff the CCS's BBs are setup, false otherwise. 473 */ 474 static inline bool xe_bo_has_valid_ccs_bb(struct xe_bo *bo) 475 { 476 return bo->bb_ccs[XE_SRIOV_VF_CCS_READ_CTX] && 477 bo->bb_ccs[XE_SRIOV_VF_CCS_WRITE_CTX]; 478 } 479 480 static inline bool xe_bo_has_pages(struct xe_bo *bo) 481 { 482 if ((bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) || 483 xe_bo_is_vram(bo)) 484 return true; 485 486 return false; 487 } 488 489 void __xe_bo_release_dummy(struct kref *kref); 490 491 /** 492 * xe_bo_put_deferred() - Put a buffer object with delayed final freeing 493 * @bo: The bo to put. 494 * @deferred: List to which to add the buffer object if we cannot put, or 495 * NULL if the function is to put unconditionally. 496 * 497 * Since the final freeing of an object includes both sleeping and (!) 498 * memory allocation in the dma_resv individualization, it's not ok 499 * to put an object from atomic context nor from within a held lock 500 * tainted by reclaim. In such situations we want to defer the final 501 * freeing until we've exited the restricting context, or in the worst 502 * case to a workqueue. 503 * This function either puts the object if possible without the refcount 504 * reaching zero, or adds it to the @deferred list if that was not possible. 505 * The caller needs to follow up with a call to xe_bo_put_commit() to actually 506 * put the bo iff this function returns true. It's safe to always 507 * follow up with a call to xe_bo_put_commit(). 508 * TODO: It's TTM that is the villain here. Perhaps TTM should add an 509 * interface like this. 510 * 511 * Return: true if @bo was the first object put on the @freed list, 512 * false otherwise. 513 */ 514 static inline bool 515 xe_bo_put_deferred(struct xe_bo *bo, struct llist_head *deferred) 516 { 517 if (!deferred) { 518 xe_bo_put(bo); 519 return false; 520 } 521 522 if (!kref_put(&bo->ttm.base.refcount, __xe_bo_release_dummy)) 523 return false; 524 525 return llist_add(&bo->freed, deferred); 526 } 527 528 void xe_bo_put_commit(struct llist_head *deferred); 529 530 /** 531 * xe_bo_put_async() - Put BO async 532 * @bo: The bo to put. 533 * 534 * Put BO async, the final put is deferred to a worker to exit an IRQ context. 535 */ 536 static inline void 537 xe_bo_put_async(struct xe_bo *bo) 538 { 539 struct xe_bo_dev *bo_device = &xe_bo_device(bo)->bo_device; 540 541 if (xe_bo_put_deferred(bo, &bo_device->async_list)) 542 schedule_work(&bo_device->async_free); 543 } 544 545 void xe_bo_dev_init(struct xe_bo_dev *bo_device); 546 547 void xe_bo_dev_fini(struct xe_bo_dev *bo_device); 548 549 struct sg_table *xe_bo_sg(struct xe_bo *bo); 550 551 /* 552 * xe_sg_segment_size() - Provides upper limit for sg segment size. 553 * @dev: device pointer 554 * 555 * Returns the maximum segment size for the 'struct scatterlist' 556 * elements. 557 */ 558 static inline unsigned int xe_sg_segment_size(struct device *dev) 559 { 560 struct scatterlist __maybe_unused sg; 561 size_t max = BIT_ULL(sizeof(sg.length) * 8) - 1; 562 563 max = min_t(size_t, max, dma_max_mapping_size(dev)); 564 565 /* 566 * The iommu_dma_map_sg() function ensures iova allocation doesn't 567 * cross dma segment boundary. It does so by padding some sg elements. 568 * This can cause overflow, ending up with sg->length being set to 0. 569 * Avoid this by ensuring maximum segment size is half of 'max' 570 * rounded down to PAGE_SIZE. 571 */ 572 return round_down(max / 2, PAGE_SIZE); 573 } 574 575 /** 576 * struct xe_bo_shrink_flags - flags governing the shrink behaviour. 577 * @purge: Only purging allowed. Don't shrink if bo not purgeable. 578 * @writeback: Attempt to immediately move content to swap. 579 */ 580 struct xe_bo_shrink_flags { 581 u32 purge : 1; 582 u32 writeback : 1; 583 }; 584 585 long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, 586 const struct xe_bo_shrink_flags flags, 587 unsigned long *scanned); 588 589 /** 590 * xe_bo_is_mem_type - Whether the bo currently resides in the given 591 * TTM memory type 592 * @bo: The bo to check. 593 * @mem_type: The TTM memory type. 594 * 595 * Return: true iff the bo resides in @mem_type, false otherwise. 596 */ 597 static inline bool xe_bo_is_mem_type(struct xe_bo *bo, u32 mem_type) 598 { 599 xe_bo_assert_held(bo); 600 return bo->ttm.resource->mem_type == mem_type; 601 } 602 #endif 603