xref: /linux/mm/slab.h (revision a97f9c8fcc6ed16f956346368fde3b1198163f6c)
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 __page_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 							unsigned frozen:1;
77 						};
78 					};
79 				};
80 #ifdef system_has_freelist_aba
81 				freelist_aba_t freelist_counter;
82 #endif
83 			};
84 		};
85 		struct rcu_head rcu_head;
86 	};
87 	unsigned int __unused;
88 
89 	atomic_t __page_refcount;
90 #ifdef CONFIG_MEMCG
91 	unsigned long memcg_data;
92 #endif
93 };
94 
95 #define SLAB_MATCH(pg, sl)						\
96 	static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl))
97 SLAB_MATCH(flags, __page_flags);
98 SLAB_MATCH(compound_head, slab_cache);	/* Ensure bit 0 is clear */
99 SLAB_MATCH(_refcount, __page_refcount);
100 #ifdef CONFIG_MEMCG
101 SLAB_MATCH(memcg_data, memcg_data);
102 #endif
103 #undef SLAB_MATCH
104 static_assert(sizeof(struct slab) <= sizeof(struct page));
105 #if defined(system_has_freelist_aba)
106 static_assert(IS_ALIGNED(offsetof(struct slab, freelist), sizeof(freelist_aba_t)));
107 #endif
108 
109 /**
110  * folio_slab - Converts from folio to slab.
111  * @folio: The folio.
112  *
113  * Currently struct slab is a different representation of a folio where
114  * folio_test_slab() is true.
115  *
116  * Return: The slab which contains this folio.
117  */
118 #define folio_slab(folio)	(_Generic((folio),			\
119 	const struct folio *:	(const struct slab *)(folio),		\
120 	struct folio *:		(struct slab *)(folio)))
121 
122 /**
123  * slab_folio - The folio allocated for a slab
124  * @slab: The slab.
125  *
126  * Slabs are allocated as folios that contain the individual objects and are
127  * using some fields in the first struct page of the folio - those fields are
128  * now accessed by struct slab. It is occasionally necessary to convert back to
129  * a folio in order to communicate with the rest of the mm.  Please use this
130  * helper function instead of casting yourself, as the implementation may change
131  * in the future.
132  */
133 #define slab_folio(s)		(_Generic((s),				\
134 	const struct slab *:	(const struct folio *)s,		\
135 	struct slab *:		(struct folio *)s))
136 
137 /**
138  * page_slab - Converts from first struct page to slab.
139  * @p: The first (either head of compound or single) page of slab.
140  *
141  * A temporary wrapper to convert struct page to struct slab in situations where
142  * we know the page is the compound head, or single order-0 page.
143  *
144  * Long-term ideally everything would work with struct slab directly or go
145  * through folio to struct slab.
146  *
147  * Return: The slab which contains this page
148  */
149 #define page_slab(p)		(_Generic((p),				\
150 	const struct page *:	(const struct slab *)(p),		\
151 	struct page *:		(struct slab *)(p)))
152 
153 /**
154  * slab_page - The first struct page allocated for a slab
155  * @slab: The slab.
156  *
157  * A convenience wrapper for converting slab to the first struct page of the
158  * underlying folio, to communicate with code not yet converted to folio or
159  * struct slab.
160  */
161 #define slab_page(s) folio_page(slab_folio(s), 0)
162 
163 /*
164  * If network-based swap is enabled, sl*b must keep track of whether pages
165  * were allocated from pfmemalloc reserves.
166  */
167 static inline bool slab_test_pfmemalloc(const struct slab *slab)
168 {
169 	return folio_test_active((struct folio *)slab_folio(slab));
170 }
171 
172 static inline void slab_set_pfmemalloc(struct slab *slab)
173 {
174 	folio_set_active(slab_folio(slab));
175 }
176 
177 static inline void slab_clear_pfmemalloc(struct slab *slab)
178 {
179 	folio_clear_active(slab_folio(slab));
180 }
181 
182 static inline void __slab_clear_pfmemalloc(struct slab *slab)
183 {
184 	__folio_clear_active(slab_folio(slab));
185 }
186 
187 static inline void *slab_address(const struct slab *slab)
188 {
189 	return folio_address(slab_folio(slab));
190 }
191 
192 static inline int slab_nid(const struct slab *slab)
193 {
194 	return folio_nid(slab_folio(slab));
195 }
196 
197 static inline pg_data_t *slab_pgdat(const struct slab *slab)
198 {
199 	return folio_pgdat(slab_folio(slab));
200 }
201 
202 static inline struct slab *virt_to_slab(const void *addr)
203 {
204 	struct folio *folio = virt_to_folio(addr);
205 
206 	if (!folio_test_slab(folio))
207 		return NULL;
208 
209 	return folio_slab(folio);
210 }
211 
212 static inline int slab_order(const struct slab *slab)
213 {
214 	return folio_order((struct folio *)slab_folio(slab));
215 }
216 
217 static inline size_t slab_size(const struct slab *slab)
218 {
219 	return PAGE_SIZE << slab_order(slab);
220 }
221 
222 #ifdef CONFIG_SLUB_CPU_PARTIAL
223 #define slub_percpu_partial(c)			((c)->partial)
224 
225 #define slub_set_percpu_partial(c, p)		\
226 ({						\
227 	slub_percpu_partial(c) = (p)->next;	\
228 })
229 
230 #define slub_percpu_partial_read_once(c)	READ_ONCE(slub_percpu_partial(c))
231 #else
232 #define slub_percpu_partial(c)			NULL
233 
234 #define slub_set_percpu_partial(c, p)
235 
236 #define slub_percpu_partial_read_once(c)	NULL
237 #endif // CONFIG_SLUB_CPU_PARTIAL
238 
239 /*
240  * Word size structure that can be atomically updated or read and that
241  * contains both the order and the number of objects that a slab of the
242  * given order would contain.
243  */
244 struct kmem_cache_order_objects {
245 	unsigned int x;
246 };
247 
248 /*
249  * Slab cache management.
250  */
251 struct kmem_cache {
252 #ifndef CONFIG_SLUB_TINY
253 	struct kmem_cache_cpu __percpu *cpu_slab;
254 #endif
255 	/* Used for retrieving partial slabs, etc. */
256 	slab_flags_t flags;
257 	unsigned long min_partial;
258 	unsigned int size;		/* Object size including metadata */
259 	unsigned int object_size;	/* Object size without metadata */
260 	struct reciprocal_value reciprocal_size;
261 	unsigned int offset;		/* Free pointer offset */
262 #ifdef CONFIG_SLUB_CPU_PARTIAL
263 	/* Number of per cpu partial objects to keep around */
264 	unsigned int cpu_partial;
265 	/* Number of per cpu partial slabs to keep around */
266 	unsigned int cpu_partial_slabs;
267 #endif
268 	struct kmem_cache_order_objects oo;
269 
270 	/* Allocation and freeing of slabs */
271 	struct kmem_cache_order_objects min;
272 	gfp_t allocflags;		/* gfp flags to use on each alloc */
273 	int refcount;			/* Refcount for slab cache destroy */
274 	void (*ctor)(void *object);	/* Object constructor */
275 	unsigned int inuse;		/* Offset to metadata */
276 	unsigned int align;		/* Alignment */
277 	unsigned int red_left_pad;	/* Left redzone padding size */
278 	const char *name;		/* Name (only for display!) */
279 	struct list_head list;		/* List of slab caches */
280 #ifdef CONFIG_SYSFS
281 	struct kobject kobj;		/* For sysfs */
282 #endif
283 #ifdef CONFIG_SLAB_FREELIST_HARDENED
284 	unsigned long random;
285 #endif
286 
287 #ifdef CONFIG_NUMA
288 	/*
289 	 * Defragmentation by allocating from a remote node.
290 	 */
291 	unsigned int remote_node_defrag_ratio;
292 #endif
293 
294 #ifdef CONFIG_SLAB_FREELIST_RANDOM
295 	unsigned int *random_seq;
296 #endif
297 
298 #ifdef CONFIG_KASAN_GENERIC
299 	struct kasan_cache kasan_info;
300 #endif
301 
302 #ifdef CONFIG_HARDENED_USERCOPY
303 	unsigned int useroffset;	/* Usercopy region offset */
304 	unsigned int usersize;		/* Usercopy region size */
305 #endif
306 
307 	struct kmem_cache_node *node[MAX_NUMNODES];
308 };
309 
310 #if defined(CONFIG_SYSFS) && !defined(CONFIG_SLUB_TINY)
311 #define SLAB_SUPPORTS_SYSFS
312 void sysfs_slab_unlink(struct kmem_cache *s);
313 void sysfs_slab_release(struct kmem_cache *s);
314 #else
315 static inline void sysfs_slab_unlink(struct kmem_cache *s) { }
316 static inline void sysfs_slab_release(struct kmem_cache *s) { }
317 #endif
318 
319 void *fixup_red_left(struct kmem_cache *s, void *p);
320 
321 static inline void *nearest_obj(struct kmem_cache *cache,
322 				const struct slab *slab, void *x)
323 {
324 	void *object = x - (x - slab_address(slab)) % cache->size;
325 	void *last_object = slab_address(slab) +
326 		(slab->objects - 1) * cache->size;
327 	void *result = (unlikely(object > last_object)) ? last_object : object;
328 
329 	result = fixup_red_left(cache, result);
330 	return result;
331 }
332 
333 /* Determine object index from a given position */
334 static inline unsigned int __obj_to_index(const struct kmem_cache *cache,
335 					  void *addr, void *obj)
336 {
337 	return reciprocal_divide(kasan_reset_tag(obj) - addr,
338 				 cache->reciprocal_size);
339 }
340 
341 static inline unsigned int obj_to_index(const struct kmem_cache *cache,
342 					const struct slab *slab, void *obj)
343 {
344 	if (is_kfence_address(obj))
345 		return 0;
346 	return __obj_to_index(cache, slab_address(slab), obj);
347 }
348 
349 static inline int objs_per_slab(const struct kmem_cache *cache,
350 				const struct slab *slab)
351 {
352 	return slab->objects;
353 }
354 
355 /*
356  * State of the slab allocator.
357  *
358  * This is used to describe the states of the allocator during bootup.
359  * Allocators use this to gradually bootstrap themselves. Most allocators
360  * have the problem that the structures used for managing slab caches are
361  * allocated from slab caches themselves.
362  */
363 enum slab_state {
364 	DOWN,			/* No slab functionality yet */
365 	PARTIAL,		/* SLUB: kmem_cache_node available */
366 	PARTIAL_NODE,		/* SLAB: kmalloc size for node struct available */
367 	UP,			/* Slab caches usable but not all extras yet */
368 	FULL			/* Everything is working */
369 };
370 
371 extern enum slab_state slab_state;
372 
373 /* The slab cache mutex protects the management structures during changes */
374 extern struct mutex slab_mutex;
375 
376 /* The list of all slab caches on the system */
377 extern struct list_head slab_caches;
378 
379 /* The slab cache that manages slab cache information */
380 extern struct kmem_cache *kmem_cache;
381 
382 /* A table of kmalloc cache names and sizes */
383 extern const struct kmalloc_info_struct {
384 	const char *name[NR_KMALLOC_TYPES];
385 	unsigned int size;
386 } kmalloc_info[];
387 
388 /* Kmalloc array related functions */
389 void setup_kmalloc_cache_index_table(void);
390 void create_kmalloc_caches(slab_flags_t);
391 
392 extern u8 kmalloc_size_index[24];
393 
394 static inline unsigned int size_index_elem(unsigned int bytes)
395 {
396 	return (bytes - 1) / 8;
397 }
398 
399 /*
400  * Find the kmem_cache structure that serves a given size of
401  * allocation
402  *
403  * This assumes size is larger than zero and not larger than
404  * KMALLOC_MAX_CACHE_SIZE and the caller must check that.
405  */
406 static inline struct kmem_cache *
407 kmalloc_slab(size_t size, gfp_t flags, unsigned long caller)
408 {
409 	unsigned int index;
410 
411 	if (size <= 192)
412 		index = kmalloc_size_index[size_index_elem(size)];
413 	else
414 		index = fls(size - 1);
415 
416 	return kmalloc_caches[kmalloc_type(flags, caller)][index];
417 }
418 
419 gfp_t kmalloc_fix_flags(gfp_t flags);
420 
421 /* Functions provided by the slab allocators */
422 int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
423 
424 void __init kmem_cache_init(void);
425 void __init new_kmalloc_cache(int idx, enum kmalloc_cache_type type,
426 			      slab_flags_t flags);
427 extern void create_boot_cache(struct kmem_cache *, const char *name,
428 			unsigned int size, slab_flags_t flags,
429 			unsigned int useroffset, unsigned int usersize);
430 
431 int slab_unmergeable(struct kmem_cache *s);
432 struct kmem_cache *find_mergeable(unsigned size, unsigned align,
433 		slab_flags_t flags, const char *name, void (*ctor)(void *));
434 struct kmem_cache *
435 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
436 		   slab_flags_t flags, void (*ctor)(void *));
437 
438 slab_flags_t kmem_cache_flags(unsigned int object_size,
439 	slab_flags_t flags, const char *name);
440 
441 static inline bool is_kmalloc_cache(struct kmem_cache *s)
442 {
443 	return (s->flags & SLAB_KMALLOC);
444 }
445 
446 /* Legal flag mask for kmem_cache_create(), for various configurations */
447 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
448 			 SLAB_CACHE_DMA32 | SLAB_PANIC | \
449 			 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
450 
451 #ifdef CONFIG_SLUB_DEBUG
452 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
453 			  SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
454 #else
455 #define SLAB_DEBUG_FLAGS (0)
456 #endif
457 
458 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
459 			  SLAB_TEMPORARY | SLAB_ACCOUNT | \
460 			  SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE)
461 
462 /* Common flags available with current configuration */
463 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
464 
465 /* Common flags permitted for kmem_cache_create */
466 #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
467 			      SLAB_RED_ZONE | \
468 			      SLAB_POISON | \
469 			      SLAB_STORE_USER | \
470 			      SLAB_TRACE | \
471 			      SLAB_CONSISTENCY_CHECKS | \
472 			      SLAB_MEM_SPREAD | \
473 			      SLAB_NOLEAKTRACE | \
474 			      SLAB_RECLAIM_ACCOUNT | \
475 			      SLAB_TEMPORARY | \
476 			      SLAB_ACCOUNT | \
477 			      SLAB_KMALLOC | \
478 			      SLAB_NO_MERGE | \
479 			      SLAB_NO_USER_FLAGS)
480 
481 bool __kmem_cache_empty(struct kmem_cache *);
482 int __kmem_cache_shutdown(struct kmem_cache *);
483 void __kmem_cache_release(struct kmem_cache *);
484 int __kmem_cache_shrink(struct kmem_cache *);
485 void slab_kmem_cache_release(struct kmem_cache *);
486 
487 struct seq_file;
488 struct file;
489 
490 struct slabinfo {
491 	unsigned long active_objs;
492 	unsigned long num_objs;
493 	unsigned long active_slabs;
494 	unsigned long num_slabs;
495 	unsigned long shared_avail;
496 	unsigned int limit;
497 	unsigned int batchcount;
498 	unsigned int shared;
499 	unsigned int objects_per_slab;
500 	unsigned int cache_order;
501 };
502 
503 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
504 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
505 ssize_t slabinfo_write(struct file *file, const char __user *buffer,
506 		       size_t count, loff_t *ppos);
507 
508 #ifdef CONFIG_SLUB_DEBUG
509 #ifdef CONFIG_SLUB_DEBUG_ON
510 DECLARE_STATIC_KEY_TRUE(slub_debug_enabled);
511 #else
512 DECLARE_STATIC_KEY_FALSE(slub_debug_enabled);
513 #endif
514 extern void print_tracking(struct kmem_cache *s, void *object);
515 long validate_slab_cache(struct kmem_cache *s);
516 static inline bool __slub_debug_enabled(void)
517 {
518 	return static_branch_unlikely(&slub_debug_enabled);
519 }
520 #else
521 static inline void print_tracking(struct kmem_cache *s, void *object)
522 {
523 }
524 static inline bool __slub_debug_enabled(void)
525 {
526 	return false;
527 }
528 #endif
529 
530 /*
531  * Returns true if any of the specified slub_debug flags is enabled for the
532  * cache. Use only for flags parsed by setup_slub_debug() as it also enables
533  * the static key.
534  */
535 static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags)
536 {
537 	if (IS_ENABLED(CONFIG_SLUB_DEBUG))
538 		VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
539 	if (__slub_debug_enabled())
540 		return s->flags & flags;
541 	return false;
542 }
543 
544 #ifdef CONFIG_MEMCG_KMEM
545 /*
546  * slab_objcgs - get the object cgroups vector associated with a slab
547  * @slab: a pointer to the slab struct
548  *
549  * Returns a pointer to the object cgroups vector associated with the slab,
550  * or NULL if no such vector has been associated yet.
551  */
552 static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
553 {
554 	unsigned long memcg_data = READ_ONCE(slab->memcg_data);
555 
556 	VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS),
557 							slab_page(slab));
558 	VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab));
559 
560 	return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
561 }
562 
563 int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
564 				 gfp_t gfp, bool new_slab);
565 void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
566 		     enum node_stat_item idx, int nr);
567 #else /* CONFIG_MEMCG_KMEM */
568 static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
569 {
570 	return NULL;
571 }
572 
573 static inline int memcg_alloc_slab_cgroups(struct slab *slab,
574 					       struct kmem_cache *s, gfp_t gfp,
575 					       bool new_slab)
576 {
577 	return 0;
578 }
579 #endif /* CONFIG_MEMCG_KMEM */
580 
581 size_t __ksize(const void *objp);
582 
583 static inline size_t slab_ksize(const struct kmem_cache *s)
584 {
585 #ifdef CONFIG_SLUB_DEBUG
586 	/*
587 	 * Debugging requires use of the padding between object
588 	 * and whatever may come after it.
589 	 */
590 	if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
591 		return s->object_size;
592 #endif
593 	if (s->flags & SLAB_KASAN)
594 		return s->object_size;
595 	/*
596 	 * If we have the need to store the freelist pointer
597 	 * back there or track user information then we can
598 	 * only use the space before that information.
599 	 */
600 	if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
601 		return s->inuse;
602 	/*
603 	 * Else we can use all the padding etc for the allocation
604 	 */
605 	return s->size;
606 }
607 
608 #ifdef CONFIG_SLUB_DEBUG
609 void dump_unreclaimable_slab(void);
610 #else
611 static inline void dump_unreclaimable_slab(void)
612 {
613 }
614 #endif
615 
616 void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
617 
618 #ifdef CONFIG_SLAB_FREELIST_RANDOM
619 int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
620 			gfp_t gfp);
621 void cache_random_seq_destroy(struct kmem_cache *cachep);
622 #else
623 static inline int cache_random_seq_create(struct kmem_cache *cachep,
624 					unsigned int count, gfp_t gfp)
625 {
626 	return 0;
627 }
628 static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
629 #endif /* CONFIG_SLAB_FREELIST_RANDOM */
630 
631 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c)
632 {
633 	if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
634 				&init_on_alloc)) {
635 		if (c->ctor)
636 			return false;
637 		if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))
638 			return flags & __GFP_ZERO;
639 		return true;
640 	}
641 	return flags & __GFP_ZERO;
642 }
643 
644 static inline bool slab_want_init_on_free(struct kmem_cache *c)
645 {
646 	if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
647 				&init_on_free))
648 		return !(c->ctor ||
649 			 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)));
650 	return false;
651 }
652 
653 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG)
654 void debugfs_slab_release(struct kmem_cache *);
655 #else
656 static inline void debugfs_slab_release(struct kmem_cache *s) { }
657 #endif
658 
659 #ifdef CONFIG_PRINTK
660 #define KS_ADDRS_COUNT 16
661 struct kmem_obj_info {
662 	void *kp_ptr;
663 	struct slab *kp_slab;
664 	void *kp_objp;
665 	unsigned long kp_data_offset;
666 	struct kmem_cache *kp_slab_cache;
667 	void *kp_ret;
668 	void *kp_stack[KS_ADDRS_COUNT];
669 	void *kp_free_stack[KS_ADDRS_COUNT];
670 };
671 void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab);
672 #endif
673 
674 void __check_heap_object(const void *ptr, unsigned long n,
675 			 const struct slab *slab, bool to_user);
676 
677 #ifdef CONFIG_SLUB_DEBUG
678 void skip_orig_size_check(struct kmem_cache *s, const void *object);
679 #endif
680 
681 #endif /* MM_SLAB_H */
682