1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef MM_SLAB_H 3 #define MM_SLAB_H 4 5 #include <linux/reciprocal_div.h> 6 #include <linux/list_lru.h> 7 #include <linux/local_lock.h> 8 #include <linux/random.h> 9 #include <linux/kobject.h> 10 #include <linux/sched/mm.h> 11 #include <linux/memcontrol.h> 12 #include <linux/kfence.h> 13 #include <linux/kasan.h> 14 15 /* 16 * Internal slab definitions 17 */ 18 19 #ifdef CONFIG_64BIT 20 # ifdef system_has_cmpxchg128 21 # define system_has_freelist_aba() system_has_cmpxchg128() 22 # define try_cmpxchg_freelist try_cmpxchg128 23 # endif 24 typedef u128 freelist_full_t; 25 #else /* CONFIG_64BIT */ 26 # ifdef system_has_cmpxchg64 27 # define system_has_freelist_aba() system_has_cmpxchg64() 28 # define try_cmpxchg_freelist try_cmpxchg64 29 # endif 30 typedef u64 freelist_full_t; 31 #endif /* CONFIG_64BIT */ 32 33 #if defined(system_has_freelist_aba) && !defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) 34 #undef system_has_freelist_aba 35 #endif 36 37 /* 38 * Freelist pointer and counter to cmpxchg together, avoids the typical ABA 39 * problems with cmpxchg of just a pointer. 40 */ 41 struct freelist_counters { 42 union { 43 struct { 44 void *freelist; 45 union { 46 unsigned long counters; 47 struct { 48 unsigned inuse:16; 49 unsigned objects:15; 50 /* 51 * If slab debugging is enabled then the 52 * frozen bit can be reused to indicate 53 * that the slab was corrupted 54 */ 55 unsigned frozen:1; 56 #ifdef CONFIG_64BIT 57 /* 58 * Some optimizations use free bits in 'counters' field 59 * to save memory. In case ->stride field is not available, 60 * such optimizations are disabled. 61 */ 62 unsigned int stride; 63 #endif 64 }; 65 }; 66 }; 67 #ifdef system_has_freelist_aba 68 freelist_full_t freelist_counters; 69 #endif 70 }; 71 }; 72 73 /* Reuses the bits in struct page */ 74 struct slab { 75 memdesc_flags_t flags; 76 77 struct kmem_cache *slab_cache; 78 union { 79 struct { 80 struct list_head slab_list; 81 /* Double-word boundary */ 82 struct freelist_counters; 83 }; 84 struct rcu_head rcu_head; 85 }; 86 87 unsigned int __page_type; 88 atomic_t __page_refcount; 89 #ifdef CONFIG_SLAB_OBJ_EXT 90 unsigned long obj_exts; 91 #endif 92 }; 93 94 #define SLAB_MATCH(pg, sl) \ 95 static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) 96 SLAB_MATCH(flags, flags); 97 SLAB_MATCH(compound_info, slab_cache); /* Ensure bit 0 is clear */ 98 SLAB_MATCH(_refcount, __page_refcount); 99 #ifdef CONFIG_MEMCG 100 SLAB_MATCH(memcg_data, obj_exts); 101 #elif defined(CONFIG_SLAB_OBJ_EXT) 102 SLAB_MATCH(_unused_slab_obj_exts, obj_exts); 103 #endif 104 #undef SLAB_MATCH 105 static_assert(sizeof(struct slab) <= sizeof(struct page)); 106 #if defined(system_has_freelist_aba) 107 static_assert(IS_ALIGNED(offsetof(struct slab, freelist), sizeof(struct freelist_counters))); 108 #endif 109 110 /** 111 * slab_folio - The folio allocated for a slab 112 * @s: The slab. 113 * 114 * Slabs are allocated as folios that contain the individual objects and are 115 * using some fields in the first struct page of the folio - those fields are 116 * now accessed by struct slab. It is occasionally necessary to convert back to 117 * a folio in order to communicate with the rest of the mm. Please use this 118 * helper function instead of casting yourself, as the implementation may change 119 * in the future. 120 */ 121 #define slab_folio(s) (_Generic((s), \ 122 const struct slab *: (const struct folio *)s, \ 123 struct slab *: (struct folio *)s)) 124 125 /** 126 * page_slab - Converts from struct page to its slab. 127 * @page: A page which may or may not belong to a slab. 128 * 129 * Return: The slab which contains this page or NULL if the page does 130 * not belong to a slab. This includes pages returned from large kmalloc. 131 */ 132 static inline struct slab *page_slab(const struct page *page) 133 { 134 page = compound_head(page); 135 if (data_race(page->page_type >> 24) != PGTY_slab) 136 page = NULL; 137 138 return (struct slab *)page; 139 } 140 141 /** 142 * slab_page - The first struct page allocated for a slab 143 * @s: The slab. 144 * 145 * A convenience wrapper for converting slab to the first struct page of the 146 * underlying folio, to communicate with code not yet converted to folio or 147 * struct slab. 148 */ 149 #define slab_page(s) folio_page(slab_folio(s), 0) 150 151 static inline void *slab_address(const struct slab *slab) 152 { 153 return folio_address(slab_folio(slab)); 154 } 155 156 static inline int slab_nid(const struct slab *slab) 157 { 158 return memdesc_nid(slab->flags); 159 } 160 161 static inline pg_data_t *slab_pgdat(const struct slab *slab) 162 { 163 return NODE_DATA(slab_nid(slab)); 164 } 165 166 static inline struct slab *virt_to_slab(const void *addr) 167 { 168 return page_slab(virt_to_page(addr)); 169 } 170 171 static inline int slab_order(const struct slab *slab) 172 { 173 return folio_order(slab_folio(slab)); 174 } 175 176 static inline size_t slab_size(const struct slab *slab) 177 { 178 return PAGE_SIZE << slab_order(slab); 179 } 180 181 /* 182 * Word size structure that can be atomically updated or read and that 183 * contains both the order and the number of objects that a slab of the 184 * given order would contain. 185 */ 186 struct kmem_cache_order_objects { 187 unsigned int x; 188 }; 189 190 struct kmem_cache_per_node_ptrs { 191 struct node_barn *barn; 192 struct kmem_cache_node *node; 193 }; 194 195 /* 196 * Slab cache management. 197 */ 198 struct kmem_cache { 199 struct slub_percpu_sheaves __percpu *cpu_sheaves; 200 /* Used for retrieving partial slabs, etc. */ 201 slab_flags_t flags; 202 unsigned long min_partial; 203 unsigned int size; /* Object size including metadata */ 204 unsigned int object_size; /* Object size without metadata */ 205 struct reciprocal_value reciprocal_size; 206 unsigned int offset; /* Free pointer offset */ 207 unsigned int sheaf_capacity; 208 struct kmem_cache_order_objects oo; 209 210 /* Allocation and freeing of slabs */ 211 struct kmem_cache_order_objects min; 212 gfp_t allocflags; /* gfp flags to use on each alloc */ 213 int refcount; /* Refcount for slab cache destroy */ 214 void (*ctor)(void *object); /* Object constructor */ 215 unsigned int inuse; /* Offset to metadata */ 216 unsigned int align; /* Alignment */ 217 unsigned int red_left_pad; /* Left redzone padding size */ 218 const char *name; /* Name (only for display!) */ 219 struct list_head list; /* List of slab caches */ 220 #ifdef CONFIG_SYSFS 221 struct kobject kobj; /* For sysfs */ 222 #endif 223 #ifdef CONFIG_SLAB_FREELIST_HARDENED 224 unsigned long random; 225 #endif 226 227 #ifdef CONFIG_NUMA 228 /* 229 * Defragmentation by allocating from a remote node. 230 */ 231 unsigned int remote_node_defrag_ratio; 232 #endif 233 234 #ifdef CONFIG_SLAB_FREELIST_RANDOM 235 unsigned int *random_seq; 236 #endif 237 238 #ifdef CONFIG_KASAN_GENERIC 239 struct kasan_cache kasan_info; 240 #endif 241 242 #ifdef CONFIG_HARDENED_USERCOPY 243 unsigned int useroffset; /* Usercopy region offset */ 244 unsigned int usersize; /* Usercopy region size */ 245 #endif 246 247 #ifdef CONFIG_SLUB_STATS 248 struct kmem_cache_stats __percpu *cpu_stats; 249 #endif 250 251 struct kmem_cache_per_node_ptrs per_node[MAX_NUMNODES]; 252 }; 253 254 /* 255 * Every cache has !NULL s->cpu_sheaves but they may point to the 256 * bootstrap_sheaf temporarily during init, or permanently for the boot caches 257 * and caches with debugging enabled, or all caches with CONFIG_SLUB_TINY. This 258 * helper distinguishes whether cache has real non-bootstrap sheaves. 259 */ 260 static inline bool cache_has_sheaves(struct kmem_cache *s) 261 { 262 /* Test CONFIG_SLUB_TINY for code elimination purposes */ 263 return !IS_ENABLED(CONFIG_SLUB_TINY) && s->sheaf_capacity; 264 } 265 266 #if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) 267 #define SLAB_SUPPORTS_SYSFS 1 268 void sysfs_slab_unlink(struct kmem_cache *s); 269 void sysfs_slab_release(struct kmem_cache *s); 270 int sysfs_slab_alias(struct kmem_cache *s, const char *name); 271 #else 272 static inline void sysfs_slab_unlink(struct kmem_cache *s) { } 273 static inline void sysfs_slab_release(struct kmem_cache *s) { } 274 static inline int sysfs_slab_alias(struct kmem_cache *s, const char *name) 275 { return 0; } 276 #endif 277 278 void *fixup_red_left(struct kmem_cache *s, void *p); 279 280 static inline void *nearest_obj(struct kmem_cache *cache, 281 const struct slab *slab, void *x) 282 { 283 void *object = x - (x - slab_address(slab)) % cache->size; 284 void *last_object = slab_address(slab) + 285 (slab->objects - 1) * cache->size; 286 void *result = (unlikely(object > last_object)) ? last_object : object; 287 288 result = fixup_red_left(cache, result); 289 return result; 290 } 291 292 /* Determine object index from a given position */ 293 static inline unsigned int __obj_to_index(const struct kmem_cache *cache, 294 void *addr, const void *obj) 295 { 296 return reciprocal_divide(kasan_reset_tag(obj) - addr, 297 cache->reciprocal_size); 298 } 299 300 static inline unsigned int obj_to_index(const struct kmem_cache *cache, 301 const struct slab *slab, const void *obj) 302 { 303 if (is_kfence_address(obj)) 304 return 0; 305 return __obj_to_index(cache, slab_address(slab), obj); 306 } 307 308 static inline int objs_per_slab(const struct kmem_cache *cache, 309 const struct slab *slab) 310 { 311 return slab->objects; 312 } 313 314 /* 315 * State of the slab allocator. 316 * 317 * This is used to describe the states of the allocator during bootup. 318 * Allocators use this to gradually bootstrap themselves. Most allocators 319 * have the problem that the structures used for managing slab caches are 320 * allocated from slab caches themselves. 321 */ 322 enum slab_state { 323 DOWN, /* No slab functionality yet */ 324 PARTIAL, /* SLUB: kmem_cache_node available */ 325 UP, /* Slab caches usable but not all extras yet */ 326 FULL /* Everything is working */ 327 }; 328 329 extern enum slab_state slab_state; 330 331 /* The slab cache mutex protects the management structures during changes */ 332 extern struct mutex slab_mutex; 333 334 /* The list of all slab caches on the system */ 335 extern struct list_head slab_caches; 336 337 /* The slab cache that manages slab cache information */ 338 extern struct kmem_cache *kmem_cache; 339 340 /* A table of kmalloc cache names and sizes */ 341 extern const struct kmalloc_info_struct { 342 const char *name[NR_KMALLOC_TYPES]; 343 unsigned int size; 344 } kmalloc_info[]; 345 346 /* Kmalloc array related functions */ 347 void setup_kmalloc_cache_index_table(void); 348 void create_kmalloc_caches(void); 349 350 extern u8 kmalloc_size_index[24]; 351 352 static inline unsigned int size_index_elem(unsigned int bytes) 353 { 354 return (bytes - 1) / 8; 355 } 356 357 /* 358 * Find the kmem_cache structure that serves a given size of 359 * allocation 360 * 361 * This assumes size is larger than zero and not larger than 362 * KMALLOC_MAX_CACHE_SIZE and the caller must check that. 363 */ 364 static inline struct kmem_cache * 365 kmalloc_slab(size_t size, kmem_buckets *b, gfp_t flags, unsigned long caller) 366 { 367 unsigned int index; 368 369 if (!b) 370 b = &kmalloc_caches[kmalloc_type(flags, caller)]; 371 if (size <= 192) 372 index = kmalloc_size_index[size_index_elem(size)]; 373 else 374 index = fls(size - 1); 375 376 return (*b)[index]; 377 } 378 379 gfp_t kmalloc_fix_flags(gfp_t flags); 380 381 /* Functions provided by the slab allocators */ 382 int do_kmem_cache_create(struct kmem_cache *s, const char *name, 383 unsigned int size, struct kmem_cache_args *args, 384 slab_flags_t flags); 385 386 void __init kmem_cache_init(void); 387 extern void create_boot_cache(struct kmem_cache *, const char *name, 388 unsigned int size, slab_flags_t flags, 389 unsigned int useroffset, unsigned int usersize); 390 391 int slab_unmergeable(struct kmem_cache *s); 392 bool slab_args_unmergeable(struct kmem_cache_args *args, slab_flags_t flags); 393 394 slab_flags_t kmem_cache_flags(slab_flags_t flags, const char *name); 395 396 static inline bool is_kmalloc_cache(struct kmem_cache *s) 397 { 398 return (s->flags & SLAB_KMALLOC); 399 } 400 401 static inline bool is_kmalloc_normal(struct kmem_cache *s) 402 { 403 if (!is_kmalloc_cache(s)) 404 return false; 405 return !(s->flags & (SLAB_CACHE_DMA|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT)); 406 } 407 408 bool __kfree_rcu_sheaf(struct kmem_cache *s, void *obj); 409 void flush_all_rcu_sheaves(void); 410 void flush_rcu_sheaves_on_cache(struct kmem_cache *s); 411 412 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \ 413 SLAB_CACHE_DMA32 | SLAB_PANIC | \ 414 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS | \ 415 SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ 416 SLAB_TEMPORARY | SLAB_ACCOUNT | \ 417 SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE) 418 419 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ 420 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) 421 422 #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS) 423 424 bool __kmem_cache_empty(struct kmem_cache *); 425 int __kmem_cache_shutdown(struct kmem_cache *); 426 void __kmem_cache_release(struct kmem_cache *); 427 int __kmem_cache_shrink(struct kmem_cache *); 428 void slab_kmem_cache_release(struct kmem_cache *); 429 430 struct seq_file; 431 struct file; 432 433 struct slabinfo { 434 unsigned long active_objs; 435 unsigned long num_objs; 436 unsigned long active_slabs; 437 unsigned long num_slabs; 438 unsigned long shared_avail; 439 unsigned int limit; 440 unsigned int batchcount; 441 unsigned int shared; 442 unsigned int objects_per_slab; 443 unsigned int cache_order; 444 }; 445 446 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); 447 448 #ifdef CONFIG_SLUB_DEBUG 449 #ifdef CONFIG_SLUB_DEBUG_ON 450 DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); 451 #else 452 DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); 453 #endif 454 extern void print_tracking(struct kmem_cache *s, void *object); 455 long validate_slab_cache(struct kmem_cache *s); 456 static inline bool __slub_debug_enabled(void) 457 { 458 return static_branch_unlikely(&slub_debug_enabled); 459 } 460 #else 461 static inline void print_tracking(struct kmem_cache *s, void *object) 462 { 463 } 464 static inline bool __slub_debug_enabled(void) 465 { 466 return false; 467 } 468 #endif 469 470 /* 471 * Returns true if any of the specified slab_debug flags is enabled for the 472 * cache. Use only for flags parsed by setup_slub_debug() as it also enables 473 * the static key. 474 */ 475 static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) 476 { 477 if (IS_ENABLED(CONFIG_SLUB_DEBUG)) 478 VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); 479 if (__slub_debug_enabled()) 480 return s->flags & flags; 481 return false; 482 } 483 484 #if IS_ENABLED(CONFIG_SLUB_DEBUG) && IS_ENABLED(CONFIG_KUNIT) 485 bool slab_in_kunit_test(void); 486 #else 487 static inline bool slab_in_kunit_test(void) { return false; } 488 #endif 489 490 /* 491 * slub is about to manipulate internal object metadata. This memory lies 492 * outside the range of the allocated object, so accessing it would normally 493 * be reported by kasan as a bounds error. metadata_access_enable() is used 494 * to tell kasan that these accesses are OK. 495 */ 496 static inline void metadata_access_enable(void) 497 { 498 kasan_disable_current(); 499 kmsan_disable_current(); 500 } 501 502 static inline void metadata_access_disable(void) 503 { 504 kmsan_enable_current(); 505 kasan_enable_current(); 506 } 507 508 #ifdef CONFIG_SLAB_OBJ_EXT 509 510 /* 511 * slab_obj_exts - get the pointer to the slab object extension vector 512 * associated with a slab. 513 * @slab: a pointer to the slab struct 514 * 515 * Returns the address of the object extension vector associated with the slab, 516 * or zero if no such vector has been associated yet. 517 * Do not dereference the return value directly; use get/put_slab_obj_exts() 518 * pair and slab_obj_ext() to access individual elements. 519 * 520 * Example usage: 521 * 522 * obj_exts = slab_obj_exts(slab); 523 * if (obj_exts) { 524 * get_slab_obj_exts(obj_exts); 525 * obj_ext = slab_obj_ext(slab, obj_exts, obj_to_index(s, slab, obj)); 526 * // do something with obj_ext 527 * put_slab_obj_exts(obj_exts); 528 * } 529 * 530 * Note that the get/put semantics does not involve reference counting. 531 * Instead, it updates kasan/kmsan depth so that accesses to slabobj_ext 532 * won't be reported as access violations. 533 */ 534 static inline unsigned long slab_obj_exts(struct slab *slab) 535 { 536 unsigned long obj_exts = READ_ONCE(slab->obj_exts); 537 538 #ifdef CONFIG_MEMCG 539 /* 540 * obj_exts should be either NULL, a valid pointer with 541 * MEMCG_DATA_OBJEXTS bit set or be equal to OBJEXTS_ALLOC_FAIL. 542 */ 543 VM_BUG_ON_PAGE(obj_exts && !(obj_exts & MEMCG_DATA_OBJEXTS) && 544 obj_exts != OBJEXTS_ALLOC_FAIL, slab_page(slab)); 545 VM_BUG_ON_PAGE(obj_exts & MEMCG_DATA_KMEM, slab_page(slab)); 546 #endif 547 548 return obj_exts & ~OBJEXTS_FLAGS_MASK; 549 } 550 551 static inline void get_slab_obj_exts(unsigned long obj_exts) 552 { 553 VM_WARN_ON_ONCE(!obj_exts); 554 metadata_access_enable(); 555 } 556 557 static inline void put_slab_obj_exts(unsigned long obj_exts) 558 { 559 metadata_access_disable(); 560 } 561 562 #ifdef CONFIG_64BIT 563 static inline void slab_set_stride(struct slab *slab, unsigned int stride) 564 { 565 slab->stride = stride; 566 } 567 static inline unsigned int slab_get_stride(struct slab *slab) 568 { 569 return slab->stride; 570 } 571 #else 572 static inline void slab_set_stride(struct slab *slab, unsigned int stride) 573 { 574 VM_WARN_ON_ONCE(stride != sizeof(struct slabobj_ext)); 575 } 576 static inline unsigned int slab_get_stride(struct slab *slab) 577 { 578 return sizeof(struct slabobj_ext); 579 } 580 #endif 581 582 /* 583 * slab_obj_ext - get the pointer to the slab object extension metadata 584 * associated with an object in a slab. 585 * @slab: a pointer to the slab struct 586 * @obj_exts: a pointer to the object extension vector 587 * @index: an index of the object 588 * 589 * Returns a pointer to the object extension associated with the object. 590 * Must be called within a section covered by get/put_slab_obj_exts(). 591 */ 592 static inline struct slabobj_ext *slab_obj_ext(struct slab *slab, 593 unsigned long obj_exts, 594 unsigned int index) 595 { 596 struct slabobj_ext *obj_ext; 597 598 VM_WARN_ON_ONCE(obj_exts != slab_obj_exts(slab)); 599 600 obj_ext = (struct slabobj_ext *)(obj_exts + 601 slab_get_stride(slab) * index); 602 return kasan_reset_tag(obj_ext); 603 } 604 605 int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s, 606 gfp_t gfp, bool new_slab); 607 608 #else /* CONFIG_SLAB_OBJ_EXT */ 609 610 static inline unsigned long slab_obj_exts(struct slab *slab) 611 { 612 return 0; 613 } 614 615 static inline struct slabobj_ext *slab_obj_ext(struct slab *slab, 616 unsigned long obj_exts, 617 unsigned int index) 618 { 619 return NULL; 620 } 621 622 static inline void slab_set_stride(struct slab *slab, unsigned int stride) { } 623 static inline unsigned int slab_get_stride(struct slab *slab) { return 0; } 624 625 626 #endif /* CONFIG_SLAB_OBJ_EXT */ 627 628 static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) 629 { 630 return (s->flags & SLAB_RECLAIM_ACCOUNT) ? 631 NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; 632 } 633 634 #ifdef CONFIG_MEMCG 635 bool __memcg_slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru, 636 gfp_t flags, size_t size, void **p); 637 void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, 638 void **p, int objects, unsigned long obj_exts); 639 #endif 640 641 void kvfree_rcu_cb(struct rcu_head *head); 642 643 static inline unsigned int large_kmalloc_order(const struct page *page) 644 { 645 return page[1].flags.f & 0xff; 646 } 647 648 static inline size_t large_kmalloc_size(const struct page *page) 649 { 650 return PAGE_SIZE << large_kmalloc_order(page); 651 } 652 653 #ifdef CONFIG_SLUB_DEBUG 654 void dump_unreclaimable_slab(void); 655 #else 656 static inline void dump_unreclaimable_slab(void) 657 { 658 } 659 #endif 660 661 void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); 662 663 #ifdef CONFIG_SLAB_FREELIST_RANDOM 664 int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, 665 gfp_t gfp); 666 void cache_random_seq_destroy(struct kmem_cache *cachep); 667 #else 668 static inline int cache_random_seq_create(struct kmem_cache *cachep, 669 unsigned int count, gfp_t gfp) 670 { 671 return 0; 672 } 673 static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } 674 #endif /* CONFIG_SLAB_FREELIST_RANDOM */ 675 676 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) 677 { 678 if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, 679 &init_on_alloc)) { 680 if (c->ctor) 681 return false; 682 if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) 683 return flags & __GFP_ZERO; 684 return true; 685 } 686 return flags & __GFP_ZERO; 687 } 688 689 static inline bool slab_want_init_on_free(struct kmem_cache *c) 690 { 691 if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON, 692 &init_on_free)) 693 return !(c->ctor || 694 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))); 695 return false; 696 } 697 698 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) 699 void debugfs_slab_release(struct kmem_cache *); 700 #else 701 static inline void debugfs_slab_release(struct kmem_cache *s) { } 702 #endif 703 704 #ifdef CONFIG_PRINTK 705 #define KS_ADDRS_COUNT 16 706 struct kmem_obj_info { 707 void *kp_ptr; 708 struct slab *kp_slab; 709 void *kp_objp; 710 unsigned long kp_data_offset; 711 struct kmem_cache *kp_slab_cache; 712 void *kp_ret; 713 void *kp_stack[KS_ADDRS_COUNT]; 714 void *kp_free_stack[KS_ADDRS_COUNT]; 715 }; 716 void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab); 717 #endif 718 719 void __check_heap_object(const void *ptr, unsigned long n, 720 const struct slab *slab, bool to_user); 721 722 void defer_free_barrier(void); 723 724 static inline bool slub_debug_orig_size(struct kmem_cache *s) 725 { 726 return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && 727 (s->flags & SLAB_KMALLOC)); 728 } 729 730 #ifdef CONFIG_SLUB_DEBUG 731 void skip_orig_size_check(struct kmem_cache *s, const void *object); 732 #endif 733 734 #endif /* MM_SLAB_H */ 735