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