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 #define this_cpu_try_cmpxchg_freelist this_cpu_try_cmpxchg128 25 typedef u128 freelist_full_t; 26 #else /* CONFIG_64BIT */ 27 # ifdef system_has_cmpxchg64 28 # define system_has_freelist_aba() system_has_cmpxchg64() 29 # define try_cmpxchg_freelist try_cmpxchg64 30 # endif 31 #define this_cpu_try_cmpxchg_freelist this_cpu_try_cmpxchg64 32 typedef u64 freelist_full_t; 33 #endif /* CONFIG_64BIT */ 34 35 #if defined(system_has_freelist_aba) && !defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) 36 #undef system_has_freelist_aba 37 #endif 38 39 /* 40 * Freelist pointer and counter to cmpxchg together, avoids the typical ABA 41 * problems with cmpxchg of just a pointer. 42 */ 43 struct freelist_counters { 44 union { 45 struct { 46 void *freelist; 47 union { 48 unsigned long counters; 49 struct { 50 unsigned inuse:16; 51 unsigned objects:15; 52 /* 53 * If slab debugging is enabled then the 54 * frozen bit can be reused to indicate 55 * that the slab was corrupted 56 */ 57 unsigned frozen:1; 58 }; 59 }; 60 }; 61 #ifdef system_has_freelist_aba 62 freelist_full_t freelist_counters; 63 #endif 64 }; 65 }; 66 67 /* Reuses the bits in struct page */ 68 struct slab { 69 memdesc_flags_t flags; 70 71 struct kmem_cache *slab_cache; 72 union { 73 struct { 74 union { 75 struct list_head slab_list; 76 struct { /* For deferred deactivate_slab() */ 77 struct llist_node llnode; 78 void *flush_freelist; 79 }; 80 #ifdef CONFIG_SLUB_CPU_PARTIAL 81 struct { 82 struct slab *next; 83 int slabs; /* Nr of slabs left */ 84 }; 85 #endif 86 }; 87 /* Double-word boundary */ 88 struct freelist_counters; 89 }; 90 struct rcu_head rcu_head; 91 }; 92 93 unsigned int __page_type; 94 atomic_t __page_refcount; 95 #ifdef CONFIG_SLAB_OBJ_EXT 96 unsigned long obj_exts; 97 #endif 98 }; 99 100 #define SLAB_MATCH(pg, sl) \ 101 static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl)) 102 SLAB_MATCH(flags, flags); 103 SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */ 104 SLAB_MATCH(_refcount, __page_refcount); 105 #ifdef CONFIG_MEMCG 106 SLAB_MATCH(memcg_data, obj_exts); 107 #elif defined(CONFIG_SLAB_OBJ_EXT) 108 SLAB_MATCH(_unused_slab_obj_exts, obj_exts); 109 #endif 110 #undef SLAB_MATCH 111 static_assert(sizeof(struct slab) <= sizeof(struct page)); 112 #if defined(system_has_freelist_aba) 113 static_assert(IS_ALIGNED(offsetof(struct slab, freelist), sizeof(struct freelist_counters))); 114 #endif 115 116 /** 117 * slab_folio - The folio allocated for a slab 118 * @s: The slab. 119 * 120 * Slabs are allocated as folios that contain the individual objects and are 121 * using some fields in the first struct page of the folio - those fields are 122 * now accessed by struct slab. It is occasionally necessary to convert back to 123 * a folio in order to communicate with the rest of the mm. Please use this 124 * helper function instead of casting yourself, as the implementation may change 125 * in the future. 126 */ 127 #define slab_folio(s) (_Generic((s), \ 128 const struct slab *: (const struct folio *)s, \ 129 struct slab *: (struct folio *)s)) 130 131 /** 132 * page_slab - Converts from struct page to its slab. 133 * @page: A page which may or may not belong to a slab. 134 * 135 * Return: The slab which contains this page or NULL if the page does 136 * not belong to a slab. This includes pages returned from large kmalloc. 137 */ 138 static inline struct slab *page_slab(const struct page *page) 139 { 140 unsigned long head; 141 142 head = READ_ONCE(page->compound_head); 143 if (head & 1) 144 page = (struct page *)(head - 1); 145 if (data_race(page->page_type >> 24) != PGTY_slab) 146 page = NULL; 147 148 return (struct slab *)page; 149 } 150 151 /** 152 * slab_page - The first struct page allocated for a slab 153 * @s: The slab. 154 * 155 * A convenience wrapper for converting slab to the first struct page of the 156 * underlying folio, to communicate with code not yet converted to folio or 157 * struct slab. 158 */ 159 #define slab_page(s) folio_page(slab_folio(s), 0) 160 161 static inline void *slab_address(const struct slab *slab) 162 { 163 return folio_address(slab_folio(slab)); 164 } 165 166 static inline int slab_nid(const struct slab *slab) 167 { 168 return memdesc_nid(slab->flags); 169 } 170 171 static inline pg_data_t *slab_pgdat(const struct slab *slab) 172 { 173 return NODE_DATA(slab_nid(slab)); 174 } 175 176 static inline struct slab *virt_to_slab(const void *addr) 177 { 178 return page_slab(virt_to_page(addr)); 179 } 180 181 static inline int slab_order(const struct slab *slab) 182 { 183 return folio_order(slab_folio(slab)); 184 } 185 186 static inline size_t slab_size(const struct slab *slab) 187 { 188 return PAGE_SIZE << slab_order(slab); 189 } 190 191 #ifdef CONFIG_SLUB_CPU_PARTIAL 192 #define slub_percpu_partial(c) ((c)->partial) 193 194 #define slub_set_percpu_partial(c, p) \ 195 ({ \ 196 slub_percpu_partial(c) = (p)->next; \ 197 }) 198 199 #define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c)) 200 #else 201 #define slub_percpu_partial(c) NULL 202 203 #define slub_set_percpu_partial(c, p) 204 205 #define slub_percpu_partial_read_once(c) NULL 206 #endif // CONFIG_SLUB_CPU_PARTIAL 207 208 /* 209 * Word size structure that can be atomically updated or read and that 210 * contains both the order and the number of objects that a slab of the 211 * given order would contain. 212 */ 213 struct kmem_cache_order_objects { 214 unsigned int x; 215 }; 216 217 /* 218 * Slab cache management. 219 */ 220 struct kmem_cache { 221 struct kmem_cache_cpu __percpu *cpu_slab; 222 struct lock_class_key lock_key; 223 struct slub_percpu_sheaves __percpu *cpu_sheaves; 224 /* Used for retrieving partial slabs, etc. */ 225 slab_flags_t flags; 226 unsigned long min_partial; 227 unsigned int size; /* Object size including metadata */ 228 unsigned int object_size; /* Object size without metadata */ 229 struct reciprocal_value reciprocal_size; 230 unsigned int offset; /* Free pointer offset */ 231 #ifdef CONFIG_SLUB_CPU_PARTIAL 232 /* Number of per cpu partial objects to keep around */ 233 unsigned int cpu_partial; 234 /* Number of per cpu partial slabs to keep around */ 235 unsigned int cpu_partial_slabs; 236 #endif 237 unsigned int sheaf_capacity; 238 struct kmem_cache_order_objects oo; 239 240 /* Allocation and freeing of slabs */ 241 struct kmem_cache_order_objects min; 242 gfp_t allocflags; /* gfp flags to use on each alloc */ 243 int refcount; /* Refcount for slab cache destroy */ 244 void (*ctor)(void *object); /* Object constructor */ 245 unsigned int inuse; /* Offset to metadata */ 246 unsigned int align; /* Alignment */ 247 unsigned int red_left_pad; /* Left redzone padding size */ 248 const char *name; /* Name (only for display!) */ 249 struct list_head list; /* List of slab caches */ 250 #ifdef CONFIG_SYSFS 251 struct kobject kobj; /* For sysfs */ 252 #endif 253 #ifdef CONFIG_SLAB_FREELIST_HARDENED 254 unsigned long random; 255 #endif 256 257 #ifdef CONFIG_NUMA 258 /* 259 * Defragmentation by allocating from a remote node. 260 */ 261 unsigned int remote_node_defrag_ratio; 262 #endif 263 264 #ifdef CONFIG_SLAB_FREELIST_RANDOM 265 unsigned int *random_seq; 266 #endif 267 268 #ifdef CONFIG_KASAN_GENERIC 269 struct kasan_cache kasan_info; 270 #endif 271 272 #ifdef CONFIG_HARDENED_USERCOPY 273 unsigned int useroffset; /* Usercopy region offset */ 274 unsigned int usersize; /* Usercopy region size */ 275 #endif 276 277 struct kmem_cache_node *node[MAX_NUMNODES]; 278 }; 279 280 #if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY) 281 #define SLAB_SUPPORTS_SYSFS 1 282 void sysfs_slab_unlink(struct kmem_cache *s); 283 void sysfs_slab_release(struct kmem_cache *s); 284 #else 285 static inline void sysfs_slab_unlink(struct kmem_cache *s) { } 286 static inline void sysfs_slab_release(struct kmem_cache *s) { } 287 #endif 288 289 void *fixup_red_left(struct kmem_cache *s, void *p); 290 291 static inline void *nearest_obj(struct kmem_cache *cache, 292 const struct slab *slab, void *x) 293 { 294 void *object = x - (x - slab_address(slab)) % cache->size; 295 void *last_object = slab_address(slab) + 296 (slab->objects - 1) * cache->size; 297 void *result = (unlikely(object > last_object)) ? last_object : object; 298 299 result = fixup_red_left(cache, result); 300 return result; 301 } 302 303 /* Determine object index from a given position */ 304 static inline unsigned int __obj_to_index(const struct kmem_cache *cache, 305 void *addr, void *obj) 306 { 307 return reciprocal_divide(kasan_reset_tag(obj) - addr, 308 cache->reciprocal_size); 309 } 310 311 static inline unsigned int obj_to_index(const struct kmem_cache *cache, 312 const struct slab *slab, void *obj) 313 { 314 if (is_kfence_address(obj)) 315 return 0; 316 return __obj_to_index(cache, slab_address(slab), obj); 317 } 318 319 static inline int objs_per_slab(const struct kmem_cache *cache, 320 const struct slab *slab) 321 { 322 return slab->objects; 323 } 324 325 /* 326 * State of the slab allocator. 327 * 328 * This is used to describe the states of the allocator during bootup. 329 * Allocators use this to gradually bootstrap themselves. Most allocators 330 * have the problem that the structures used for managing slab caches are 331 * allocated from slab caches themselves. 332 */ 333 enum slab_state { 334 DOWN, /* No slab functionality yet */ 335 PARTIAL, /* SLUB: kmem_cache_node available */ 336 UP, /* Slab caches usable but not all extras yet */ 337 FULL /* Everything is working */ 338 }; 339 340 extern enum slab_state slab_state; 341 342 /* The slab cache mutex protects the management structures during changes */ 343 extern struct mutex slab_mutex; 344 345 /* The list of all slab caches on the system */ 346 extern struct list_head slab_caches; 347 348 /* The slab cache that manages slab cache information */ 349 extern struct kmem_cache *kmem_cache; 350 351 /* A table of kmalloc cache names and sizes */ 352 extern const struct kmalloc_info_struct { 353 const char *name[NR_KMALLOC_TYPES]; 354 unsigned int size; 355 } kmalloc_info[]; 356 357 /* Kmalloc array related functions */ 358 void setup_kmalloc_cache_index_table(void); 359 void create_kmalloc_caches(void); 360 361 extern u8 kmalloc_size_index[24]; 362 363 static inline unsigned int size_index_elem(unsigned int bytes) 364 { 365 return (bytes - 1) / 8; 366 } 367 368 /* 369 * Find the kmem_cache structure that serves a given size of 370 * allocation 371 * 372 * This assumes size is larger than zero and not larger than 373 * KMALLOC_MAX_CACHE_SIZE and the caller must check that. 374 */ 375 static inline struct kmem_cache * 376 kmalloc_slab(size_t size, kmem_buckets *b, gfp_t flags, unsigned long caller) 377 { 378 unsigned int index; 379 380 if (!b) 381 b = &kmalloc_caches[kmalloc_type(flags, caller)]; 382 if (size <= 192) 383 index = kmalloc_size_index[size_index_elem(size)]; 384 else 385 index = fls(size - 1); 386 387 return (*b)[index]; 388 } 389 390 gfp_t kmalloc_fix_flags(gfp_t flags); 391 392 /* Functions provided by the slab allocators */ 393 int do_kmem_cache_create(struct kmem_cache *s, const char *name, 394 unsigned int size, struct kmem_cache_args *args, 395 slab_flags_t flags); 396 397 void __init kmem_cache_init(void); 398 extern void create_boot_cache(struct kmem_cache *, const char *name, 399 unsigned int size, slab_flags_t flags, 400 unsigned int useroffset, unsigned int usersize); 401 402 int slab_unmergeable(struct kmem_cache *s); 403 struct kmem_cache *find_mergeable(unsigned size, unsigned align, 404 slab_flags_t flags, const char *name, void (*ctor)(void *)); 405 struct kmem_cache * 406 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, 407 slab_flags_t flags, void (*ctor)(void *)); 408 409 slab_flags_t kmem_cache_flags(slab_flags_t flags, const char *name); 410 411 static inline bool is_kmalloc_cache(struct kmem_cache *s) 412 { 413 return (s->flags & SLAB_KMALLOC); 414 } 415 416 static inline bool is_kmalloc_normal(struct kmem_cache *s) 417 { 418 if (!is_kmalloc_cache(s)) 419 return false; 420 return !(s->flags & (SLAB_CACHE_DMA|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT)); 421 } 422 423 bool __kfree_rcu_sheaf(struct kmem_cache *s, void *obj); 424 void flush_all_rcu_sheaves(void); 425 426 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \ 427 SLAB_CACHE_DMA32 | SLAB_PANIC | \ 428 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS | \ 429 SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ 430 SLAB_TEMPORARY | SLAB_ACCOUNT | \ 431 SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE) 432 433 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ 434 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) 435 436 #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS) 437 438 bool __kmem_cache_empty(struct kmem_cache *); 439 int __kmem_cache_shutdown(struct kmem_cache *); 440 void __kmem_cache_release(struct kmem_cache *); 441 int __kmem_cache_shrink(struct kmem_cache *); 442 void slab_kmem_cache_release(struct kmem_cache *); 443 444 struct seq_file; 445 struct file; 446 447 struct slabinfo { 448 unsigned long active_objs; 449 unsigned long num_objs; 450 unsigned long active_slabs; 451 unsigned long num_slabs; 452 unsigned long shared_avail; 453 unsigned int limit; 454 unsigned int batchcount; 455 unsigned int shared; 456 unsigned int objects_per_slab; 457 unsigned int cache_order; 458 }; 459 460 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); 461 462 #ifdef CONFIG_SLUB_DEBUG 463 #ifdef CONFIG_SLUB_DEBUG_ON 464 DECLARE_STATIC_KEY_TRUE(slub_debug_enabled); 465 #else 466 DECLARE_STATIC_KEY_FALSE(slub_debug_enabled); 467 #endif 468 extern void print_tracking(struct kmem_cache *s, void *object); 469 long validate_slab_cache(struct kmem_cache *s); 470 static inline bool __slub_debug_enabled(void) 471 { 472 return static_branch_unlikely(&slub_debug_enabled); 473 } 474 #else 475 static inline void print_tracking(struct kmem_cache *s, void *object) 476 { 477 } 478 static inline bool __slub_debug_enabled(void) 479 { 480 return false; 481 } 482 #endif 483 484 /* 485 * Returns true if any of the specified slab_debug flags is enabled for the 486 * cache. Use only for flags parsed by setup_slub_debug() as it also enables 487 * the static key. 488 */ 489 static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags) 490 { 491 if (IS_ENABLED(CONFIG_SLUB_DEBUG)) 492 VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS)); 493 if (__slub_debug_enabled()) 494 return s->flags & flags; 495 return false; 496 } 497 498 #if IS_ENABLED(CONFIG_SLUB_DEBUG) && IS_ENABLED(CONFIG_KUNIT) 499 bool slab_in_kunit_test(void); 500 #else 501 static inline bool slab_in_kunit_test(void) { return false; } 502 #endif 503 504 #ifdef CONFIG_SLAB_OBJ_EXT 505 506 /* 507 * slab_obj_exts - get the pointer to the slab object extension vector 508 * associated with a slab. 509 * @slab: a pointer to the slab struct 510 * 511 * Returns a pointer to the object extension vector associated with the slab, 512 * or NULL if no such vector has been associated yet. 513 */ 514 static inline struct slabobj_ext *slab_obj_exts(struct slab *slab) 515 { 516 unsigned long obj_exts = READ_ONCE(slab->obj_exts); 517 518 #ifdef CONFIG_MEMCG 519 /* 520 * obj_exts should be either NULL, a valid pointer with 521 * MEMCG_DATA_OBJEXTS bit set or be equal to OBJEXTS_ALLOC_FAIL. 522 */ 523 VM_BUG_ON_PAGE(obj_exts && !(obj_exts & MEMCG_DATA_OBJEXTS) && 524 obj_exts != OBJEXTS_ALLOC_FAIL, slab_page(slab)); 525 VM_BUG_ON_PAGE(obj_exts & MEMCG_DATA_KMEM, slab_page(slab)); 526 #endif 527 return (struct slabobj_ext *)(obj_exts & ~OBJEXTS_FLAGS_MASK); 528 } 529 530 int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s, 531 gfp_t gfp, bool new_slab); 532 533 #else /* CONFIG_SLAB_OBJ_EXT */ 534 535 static inline struct slabobj_ext *slab_obj_exts(struct slab *slab) 536 { 537 return NULL; 538 } 539 540 #endif /* CONFIG_SLAB_OBJ_EXT */ 541 542 static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) 543 { 544 return (s->flags & SLAB_RECLAIM_ACCOUNT) ? 545 NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; 546 } 547 548 #ifdef CONFIG_MEMCG 549 bool __memcg_slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru, 550 gfp_t flags, size_t size, void **p); 551 void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, 552 void **p, int objects, struct slabobj_ext *obj_exts); 553 #endif 554 555 void kvfree_rcu_cb(struct rcu_head *head); 556 557 size_t __ksize(const void *objp); 558 559 static inline size_t slab_ksize(const struct kmem_cache *s) 560 { 561 #ifdef CONFIG_SLUB_DEBUG 562 /* 563 * Debugging requires use of the padding between object 564 * and whatever may come after it. 565 */ 566 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) 567 return s->object_size; 568 #endif 569 if (s->flags & SLAB_KASAN) 570 return s->object_size; 571 /* 572 * If we have the need to store the freelist pointer 573 * back there or track user information then we can 574 * only use the space before that information. 575 */ 576 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER)) 577 return s->inuse; 578 /* 579 * Else we can use all the padding etc for the allocation 580 */ 581 return s->size; 582 } 583 584 static inline unsigned int large_kmalloc_order(const struct page *page) 585 { 586 return page[1].flags.f & 0xff; 587 } 588 589 static inline size_t large_kmalloc_size(const struct page *page) 590 { 591 return PAGE_SIZE << large_kmalloc_order(page); 592 } 593 594 #ifdef CONFIG_SLUB_DEBUG 595 void dump_unreclaimable_slab(void); 596 #else 597 static inline void dump_unreclaimable_slab(void) 598 { 599 } 600 #endif 601 602 void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr); 603 604 #ifdef CONFIG_SLAB_FREELIST_RANDOM 605 int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count, 606 gfp_t gfp); 607 void cache_random_seq_destroy(struct kmem_cache *cachep); 608 #else 609 static inline int cache_random_seq_create(struct kmem_cache *cachep, 610 unsigned int count, gfp_t gfp) 611 { 612 return 0; 613 } 614 static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { } 615 #endif /* CONFIG_SLAB_FREELIST_RANDOM */ 616 617 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c) 618 { 619 if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, 620 &init_on_alloc)) { 621 if (c->ctor) 622 return false; 623 if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) 624 return flags & __GFP_ZERO; 625 return true; 626 } 627 return flags & __GFP_ZERO; 628 } 629 630 static inline bool slab_want_init_on_free(struct kmem_cache *c) 631 { 632 if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON, 633 &init_on_free)) 634 return !(c->ctor || 635 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))); 636 return false; 637 } 638 639 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) 640 void debugfs_slab_release(struct kmem_cache *); 641 #else 642 static inline void debugfs_slab_release(struct kmem_cache *s) { } 643 #endif 644 645 #ifdef CONFIG_PRINTK 646 #define KS_ADDRS_COUNT 16 647 struct kmem_obj_info { 648 void *kp_ptr; 649 struct slab *kp_slab; 650 void *kp_objp; 651 unsigned long kp_data_offset; 652 struct kmem_cache *kp_slab_cache; 653 void *kp_ret; 654 void *kp_stack[KS_ADDRS_COUNT]; 655 void *kp_free_stack[KS_ADDRS_COUNT]; 656 }; 657 void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab); 658 #endif 659 660 void __check_heap_object(const void *ptr, unsigned long n, 661 const struct slab *slab, bool to_user); 662 663 void defer_free_barrier(void); 664 665 static inline bool slub_debug_orig_size(struct kmem_cache *s) 666 { 667 return (kmem_cache_debug_flags(s, SLAB_STORE_USER) && 668 (s->flags & SLAB_KMALLOC)); 669 } 670 671 #ifdef CONFIG_SLUB_DEBUG 672 void skip_orig_size_check(struct kmem_cache *s, const void *object); 673 #endif 674 675 #endif /* MM_SLAB_H */ 676