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