Loading...
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef MM_SLAB_H
3#define MM_SLAB_H
4/*
5 * Internal slab definitions
6 */
7
8#ifdef CONFIG_SLOB
9/*
10 * Common fields provided in kmem_cache by all slab allocators
11 * This struct is either used directly by the allocator (SLOB)
12 * or the allocator must include definitions for all fields
13 * provided in kmem_cache_common in their definition of kmem_cache.
14 *
15 * Once we can do anonymous structs (C11 standard) we could put a
16 * anonymous struct definition in these allocators so that the
17 * separate allocations in the kmem_cache structure of SLAB and
18 * SLUB is no longer needed.
19 */
20struct kmem_cache {
21 unsigned int object_size;/* The original size of the object */
22 unsigned int size; /* The aligned/padded/added on size */
23 unsigned int align; /* Alignment as calculated */
24 slab_flags_t flags; /* Active flags on the slab */
25 unsigned int useroffset;/* Usercopy region offset */
26 unsigned int usersize; /* Usercopy region size */
27 const char *name; /* Slab name for sysfs */
28 int refcount; /* Use counter */
29 void (*ctor)(void *); /* Called on object slot creation */
30 struct list_head list; /* List of all slab caches on the system */
31};
32
33#endif /* CONFIG_SLOB */
34
35#ifdef CONFIG_SLAB
36#include <linux/slab_def.h>
37#endif
38
39#ifdef CONFIG_SLUB
40#include <linux/slub_def.h>
41#endif
42
43#include <linux/memcontrol.h>
44#include <linux/fault-inject.h>
45#include <linux/kasan.h>
46#include <linux/kmemleak.h>
47#include <linux/random.h>
48#include <linux/sched/mm.h>
49#include <linux/kmemleak.h>
50
51/*
52 * State of the slab allocator.
53 *
54 * This is used to describe the states of the allocator during bootup.
55 * Allocators use this to gradually bootstrap themselves. Most allocators
56 * have the problem that the structures used for managing slab caches are
57 * allocated from slab caches themselves.
58 */
59enum slab_state {
60 DOWN, /* No slab functionality yet */
61 PARTIAL, /* SLUB: kmem_cache_node available */
62 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
63 UP, /* Slab caches usable but not all extras yet */
64 FULL /* Everything is working */
65};
66
67extern enum slab_state slab_state;
68
69/* The slab cache mutex protects the management structures during changes */
70extern struct mutex slab_mutex;
71
72/* The list of all slab caches on the system */
73extern struct list_head slab_caches;
74
75/* The slab cache that manages slab cache information */
76extern struct kmem_cache *kmem_cache;
77
78/* A table of kmalloc cache names and sizes */
79extern const struct kmalloc_info_struct {
80 const char *name[NR_KMALLOC_TYPES];
81 unsigned int size;
82} kmalloc_info[];
83
84#ifndef CONFIG_SLOB
85/* Kmalloc array related functions */
86void setup_kmalloc_cache_index_table(void);
87void create_kmalloc_caches(slab_flags_t);
88
89/* Find the kmalloc slab corresponding for a certain size */
90struct kmem_cache *kmalloc_slab(size_t, gfp_t);
91#endif
92
93gfp_t kmalloc_fix_flags(gfp_t flags);
94
95/* Functions provided by the slab allocators */
96int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
97
98struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size,
99 slab_flags_t flags, unsigned int useroffset,
100 unsigned int usersize);
101extern void create_boot_cache(struct kmem_cache *, const char *name,
102 unsigned int size, slab_flags_t flags,
103 unsigned int useroffset, unsigned int usersize);
104
105int slab_unmergeable(struct kmem_cache *s);
106struct kmem_cache *find_mergeable(unsigned size, unsigned align,
107 slab_flags_t flags, const char *name, void (*ctor)(void *));
108#ifndef CONFIG_SLOB
109struct kmem_cache *
110__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
111 slab_flags_t flags, void (*ctor)(void *));
112
113slab_flags_t kmem_cache_flags(unsigned int object_size,
114 slab_flags_t flags, const char *name,
115 void (*ctor)(void *));
116#else
117static inline struct kmem_cache *
118__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
119 slab_flags_t flags, void (*ctor)(void *))
120{ return NULL; }
121
122static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
123 slab_flags_t flags, const char *name,
124 void (*ctor)(void *))
125{
126 return flags;
127}
128#endif
129
130
131/* Legal flag mask for kmem_cache_create(), for various configurations */
132#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
133 SLAB_CACHE_DMA32 | SLAB_PANIC | \
134 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
135
136#if defined(CONFIG_DEBUG_SLAB)
137#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
138#elif defined(CONFIG_SLUB_DEBUG)
139#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
140 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
141#else
142#define SLAB_DEBUG_FLAGS (0)
143#endif
144
145#if defined(CONFIG_SLAB)
146#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
147 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
148 SLAB_ACCOUNT)
149#elif defined(CONFIG_SLUB)
150#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
151 SLAB_TEMPORARY | SLAB_ACCOUNT)
152#else
153#define SLAB_CACHE_FLAGS (0)
154#endif
155
156/* Common flags available with current configuration */
157#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
158
159/* Common flags permitted for kmem_cache_create */
160#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
161 SLAB_RED_ZONE | \
162 SLAB_POISON | \
163 SLAB_STORE_USER | \
164 SLAB_TRACE | \
165 SLAB_CONSISTENCY_CHECKS | \
166 SLAB_MEM_SPREAD | \
167 SLAB_NOLEAKTRACE | \
168 SLAB_RECLAIM_ACCOUNT | \
169 SLAB_TEMPORARY | \
170 SLAB_ACCOUNT)
171
172bool __kmem_cache_empty(struct kmem_cache *);
173int __kmem_cache_shutdown(struct kmem_cache *);
174void __kmem_cache_release(struct kmem_cache *);
175int __kmem_cache_shrink(struct kmem_cache *);
176void slab_kmem_cache_release(struct kmem_cache *);
177
178struct seq_file;
179struct file;
180
181struct slabinfo {
182 unsigned long active_objs;
183 unsigned long num_objs;
184 unsigned long active_slabs;
185 unsigned long num_slabs;
186 unsigned long shared_avail;
187 unsigned int limit;
188 unsigned int batchcount;
189 unsigned int shared;
190 unsigned int objects_per_slab;
191 unsigned int cache_order;
192};
193
194void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
195void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
196ssize_t slabinfo_write(struct file *file, const char __user *buffer,
197 size_t count, loff_t *ppos);
198
199/*
200 * Generic implementation of bulk operations
201 * These are useful for situations in which the allocator cannot
202 * perform optimizations. In that case segments of the object listed
203 * may be allocated or freed using these operations.
204 */
205void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
206int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
207
208static inline int cache_vmstat_idx(struct kmem_cache *s)
209{
210 return (s->flags & SLAB_RECLAIM_ACCOUNT) ?
211 NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B;
212}
213
214#ifdef CONFIG_SLUB_DEBUG
215#ifdef CONFIG_SLUB_DEBUG_ON
216DECLARE_STATIC_KEY_TRUE(slub_debug_enabled);
217#else
218DECLARE_STATIC_KEY_FALSE(slub_debug_enabled);
219#endif
220extern void print_tracking(struct kmem_cache *s, void *object);
221#else
222static inline void print_tracking(struct kmem_cache *s, void *object)
223{
224}
225#endif
226
227/*
228 * Returns true if any of the specified slub_debug flags is enabled for the
229 * cache. Use only for flags parsed by setup_slub_debug() as it also enables
230 * the static key.
231 */
232static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags)
233{
234#ifdef CONFIG_SLUB_DEBUG
235 VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
236 if (static_branch_unlikely(&slub_debug_enabled))
237 return s->flags & flags;
238#endif
239 return false;
240}
241
242#ifdef CONFIG_MEMCG_KMEM
243static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
244{
245 /*
246 * page->mem_cgroup and page->obj_cgroups are sharing the same
247 * space. To distinguish between them in case we don't know for sure
248 * that the page is a slab page (e.g. page_cgroup_ino()), let's
249 * always set the lowest bit of obj_cgroups.
250 */
251 return (struct obj_cgroup **)
252 ((unsigned long)page->obj_cgroups & ~0x1UL);
253}
254
255static inline bool page_has_obj_cgroups(struct page *page)
256{
257 return ((unsigned long)page->obj_cgroups & 0x1UL);
258}
259
260int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
261 gfp_t gfp);
262
263static inline void memcg_free_page_obj_cgroups(struct page *page)
264{
265 kfree(page_obj_cgroups(page));
266 page->obj_cgroups = NULL;
267}
268
269static inline size_t obj_full_size(struct kmem_cache *s)
270{
271 /*
272 * For each accounted object there is an extra space which is used
273 * to store obj_cgroup membership. Charge it too.
274 */
275 return s->size + sizeof(struct obj_cgroup *);
276}
277
278static inline struct obj_cgroup *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
279 size_t objects,
280 gfp_t flags)
281{
282 struct obj_cgroup *objcg;
283
284 if (memcg_kmem_bypass())
285 return NULL;
286
287 objcg = get_obj_cgroup_from_current();
288 if (!objcg)
289 return NULL;
290
291 if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) {
292 obj_cgroup_put(objcg);
293 return NULL;
294 }
295
296 return objcg;
297}
298
299static inline void mod_objcg_state(struct obj_cgroup *objcg,
300 struct pglist_data *pgdat,
301 int idx, int nr)
302{
303 struct mem_cgroup *memcg;
304 struct lruvec *lruvec;
305
306 rcu_read_lock();
307 memcg = obj_cgroup_memcg(objcg);
308 lruvec = mem_cgroup_lruvec(memcg, pgdat);
309 mod_memcg_lruvec_state(lruvec, idx, nr);
310 rcu_read_unlock();
311}
312
313static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
314 struct obj_cgroup *objcg,
315 gfp_t flags, size_t size,
316 void **p)
317{
318 struct page *page;
319 unsigned long off;
320 size_t i;
321
322 if (!objcg)
323 return;
324
325 flags &= ~__GFP_ACCOUNT;
326 for (i = 0; i < size; i++) {
327 if (likely(p[i])) {
328 page = virt_to_head_page(p[i]);
329
330 if (!page_has_obj_cgroups(page) &&
331 memcg_alloc_page_obj_cgroups(page, s, flags)) {
332 obj_cgroup_uncharge(objcg, obj_full_size(s));
333 continue;
334 }
335
336 off = obj_to_index(s, page, p[i]);
337 obj_cgroup_get(objcg);
338 page_obj_cgroups(page)[off] = objcg;
339 mod_objcg_state(objcg, page_pgdat(page),
340 cache_vmstat_idx(s), obj_full_size(s));
341 } else {
342 obj_cgroup_uncharge(objcg, obj_full_size(s));
343 }
344 }
345 obj_cgroup_put(objcg);
346}
347
348static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page,
349 void *p)
350{
351 struct obj_cgroup *objcg;
352 unsigned int off;
353
354 if (!memcg_kmem_enabled())
355 return;
356
357 if (!page_has_obj_cgroups(page))
358 return;
359
360 off = obj_to_index(s, page, p);
361 objcg = page_obj_cgroups(page)[off];
362 page_obj_cgroups(page)[off] = NULL;
363
364 if (!objcg)
365 return;
366
367 obj_cgroup_uncharge(objcg, obj_full_size(s));
368 mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s),
369 -obj_full_size(s));
370
371 obj_cgroup_put(objcg);
372}
373
374#else /* CONFIG_MEMCG_KMEM */
375static inline bool page_has_obj_cgroups(struct page *page)
376{
377 return false;
378}
379
380static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
381{
382 return NULL;
383}
384
385static inline int memcg_alloc_page_obj_cgroups(struct page *page,
386 struct kmem_cache *s, gfp_t gfp)
387{
388 return 0;
389}
390
391static inline void memcg_free_page_obj_cgroups(struct page *page)
392{
393}
394
395static inline struct obj_cgroup *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
396 size_t objects,
397 gfp_t flags)
398{
399 return NULL;
400}
401
402static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
403 struct obj_cgroup *objcg,
404 gfp_t flags, size_t size,
405 void **p)
406{
407}
408
409static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page,
410 void *p)
411{
412}
413#endif /* CONFIG_MEMCG_KMEM */
414
415static inline struct kmem_cache *virt_to_cache(const void *obj)
416{
417 struct page *page;
418
419 page = virt_to_head_page(obj);
420 if (WARN_ONCE(!PageSlab(page), "%s: Object is not a Slab page!\n",
421 __func__))
422 return NULL;
423 return page->slab_cache;
424}
425
426static __always_inline void account_slab_page(struct page *page, int order,
427 struct kmem_cache *s)
428{
429 mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
430 PAGE_SIZE << order);
431}
432
433static __always_inline void unaccount_slab_page(struct page *page, int order,
434 struct kmem_cache *s)
435{
436 if (memcg_kmem_enabled())
437 memcg_free_page_obj_cgroups(page);
438
439 mod_node_page_state(page_pgdat(page), cache_vmstat_idx(s),
440 -(PAGE_SIZE << order));
441}
442
443static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
444{
445 struct kmem_cache *cachep;
446
447 if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) &&
448 !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS))
449 return s;
450
451 cachep = virt_to_cache(x);
452 if (WARN(cachep && cachep != s,
453 "%s: Wrong slab cache. %s but object is from %s\n",
454 __func__, s->name, cachep->name))
455 print_tracking(cachep, x);
456 return cachep;
457}
458
459static inline size_t slab_ksize(const struct kmem_cache *s)
460{
461#ifndef CONFIG_SLUB
462 return s->object_size;
463
464#else /* CONFIG_SLUB */
465# ifdef CONFIG_SLUB_DEBUG
466 /*
467 * Debugging requires use of the padding between object
468 * and whatever may come after it.
469 */
470 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
471 return s->object_size;
472# endif
473 if (s->flags & SLAB_KASAN)
474 return s->object_size;
475 /*
476 * If we have the need to store the freelist pointer
477 * back there or track user information then we can
478 * only use the space before that information.
479 */
480 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
481 return s->inuse;
482 /*
483 * Else we can use all the padding etc for the allocation
484 */
485 return s->size;
486#endif
487}
488
489static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
490 struct obj_cgroup **objcgp,
491 size_t size, gfp_t flags)
492{
493 flags &= gfp_allowed_mask;
494
495 fs_reclaim_acquire(flags);
496 fs_reclaim_release(flags);
497
498 might_sleep_if(gfpflags_allow_blocking(flags));
499
500 if (should_failslab(s, flags))
501 return NULL;
502
503 if (memcg_kmem_enabled() &&
504 ((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT)))
505 *objcgp = memcg_slab_pre_alloc_hook(s, size, flags);
506
507 return s;
508}
509
510static inline void slab_post_alloc_hook(struct kmem_cache *s,
511 struct obj_cgroup *objcg,
512 gfp_t flags, size_t size, void **p)
513{
514 size_t i;
515
516 flags &= gfp_allowed_mask;
517 for (i = 0; i < size; i++) {
518 p[i] = kasan_slab_alloc(s, p[i], flags);
519 /* As p[i] might get tagged, call kmemleak hook after KASAN. */
520 kmemleak_alloc_recursive(p[i], s->object_size, 1,
521 s->flags, flags);
522 }
523
524 if (memcg_kmem_enabled())
525 memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
526}
527
528#ifndef CONFIG_SLOB
529/*
530 * The slab lists for all objects.
531 */
532struct kmem_cache_node {
533 spinlock_t list_lock;
534
535#ifdef CONFIG_SLAB
536 struct list_head slabs_partial; /* partial list first, better asm code */
537 struct list_head slabs_full;
538 struct list_head slabs_free;
539 unsigned long total_slabs; /* length of all slab lists */
540 unsigned long free_slabs; /* length of free slab list only */
541 unsigned long free_objects;
542 unsigned int free_limit;
543 unsigned int colour_next; /* Per-node cache coloring */
544 struct array_cache *shared; /* shared per node */
545 struct alien_cache **alien; /* on other nodes */
546 unsigned long next_reap; /* updated without locking */
547 int free_touched; /* updated without locking */
548#endif
549
550#ifdef CONFIG_SLUB
551 unsigned long nr_partial;
552 struct list_head partial;
553#ifdef CONFIG_SLUB_DEBUG
554 atomic_long_t nr_slabs;
555 atomic_long_t total_objects;
556 struct list_head full;
557#endif
558#endif
559
560};
561
562static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
563{
564 return s->node[node];
565}
566
567/*
568 * Iterator over all nodes. The body will be executed for each node that has
569 * a kmem_cache_node structure allocated (which is true for all online nodes)
570 */
571#define for_each_kmem_cache_node(__s, __node, __n) \
572 for (__node = 0; __node < nr_node_ids; __node++) \
573 if ((__n = get_node(__s, __node)))
574
575#endif
576
577void *slab_start(struct seq_file *m, loff_t *pos);
578void *slab_next(struct seq_file *m, void *p, loff_t *pos);
579void slab_stop(struct seq_file *m, void *p);
580int memcg_slab_show(struct seq_file *m, void *p);
581
582#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
583void dump_unreclaimable_slab(void);
584#else
585static inline void dump_unreclaimable_slab(void)
586{
587}
588#endif
589
590void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
591
592#ifdef CONFIG_SLAB_FREELIST_RANDOM
593int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
594 gfp_t gfp);
595void cache_random_seq_destroy(struct kmem_cache *cachep);
596#else
597static inline int cache_random_seq_create(struct kmem_cache *cachep,
598 unsigned int count, gfp_t gfp)
599{
600 return 0;
601}
602static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
603#endif /* CONFIG_SLAB_FREELIST_RANDOM */
604
605static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c)
606{
607 if (static_branch_unlikely(&init_on_alloc)) {
608 if (c->ctor)
609 return false;
610 if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))
611 return flags & __GFP_ZERO;
612 return true;
613 }
614 return flags & __GFP_ZERO;
615}
616
617static inline bool slab_want_init_on_free(struct kmem_cache *c)
618{
619 if (static_branch_unlikely(&init_on_free))
620 return !(c->ctor ||
621 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)));
622 return false;
623}
624
625#endif /* MM_SLAB_H */
1#ifndef MM_SLAB_H
2#define MM_SLAB_H
3/*
4 * Internal slab definitions
5 */
6
7#ifdef CONFIG_SLOB
8/*
9 * Common fields provided in kmem_cache by all slab allocators
10 * This struct is either used directly by the allocator (SLOB)
11 * or the allocator must include definitions for all fields
12 * provided in kmem_cache_common in their definition of kmem_cache.
13 *
14 * Once we can do anonymous structs (C11 standard) we could put a
15 * anonymous struct definition in these allocators so that the
16 * separate allocations in the kmem_cache structure of SLAB and
17 * SLUB is no longer needed.
18 */
19struct kmem_cache {
20 unsigned int object_size;/* The original size of the object */
21 unsigned int size; /* The aligned/padded/added on size */
22 unsigned int align; /* Alignment as calculated */
23 unsigned long flags; /* Active flags on the slab */
24 const char *name; /* Slab name for sysfs */
25 int refcount; /* Use counter */
26 void (*ctor)(void *); /* Called on object slot creation */
27 struct list_head list; /* List of all slab caches on the system */
28};
29
30#endif /* CONFIG_SLOB */
31
32#ifdef CONFIG_SLAB
33#include <linux/slab_def.h>
34#endif
35
36#ifdef CONFIG_SLUB
37#include <linux/slub_def.h>
38#endif
39
40#include <linux/memcontrol.h>
41#include <linux/fault-inject.h>
42#include <linux/kmemcheck.h>
43#include <linux/kasan.h>
44#include <linux/kmemleak.h>
45
46/*
47 * State of the slab allocator.
48 *
49 * This is used to describe the states of the allocator during bootup.
50 * Allocators use this to gradually bootstrap themselves. Most allocators
51 * have the problem that the structures used for managing slab caches are
52 * allocated from slab caches themselves.
53 */
54enum slab_state {
55 DOWN, /* No slab functionality yet */
56 PARTIAL, /* SLUB: kmem_cache_node available */
57 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
58 UP, /* Slab caches usable but not all extras yet */
59 FULL /* Everything is working */
60};
61
62extern enum slab_state slab_state;
63
64/* The slab cache mutex protects the management structures during changes */
65extern struct mutex slab_mutex;
66
67/* The list of all slab caches on the system */
68extern struct list_head slab_caches;
69
70/* The slab cache that manages slab cache information */
71extern struct kmem_cache *kmem_cache;
72
73unsigned long calculate_alignment(unsigned long flags,
74 unsigned long align, unsigned long size);
75
76#ifndef CONFIG_SLOB
77/* Kmalloc array related functions */
78void setup_kmalloc_cache_index_table(void);
79void create_kmalloc_caches(unsigned long);
80
81/* Find the kmalloc slab corresponding for a certain size */
82struct kmem_cache *kmalloc_slab(size_t, gfp_t);
83#endif
84
85
86/* Functions provided by the slab allocators */
87extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags);
88
89extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size,
90 unsigned long flags);
91extern void create_boot_cache(struct kmem_cache *, const char *name,
92 size_t size, unsigned long flags);
93
94int slab_unmergeable(struct kmem_cache *s);
95struct kmem_cache *find_mergeable(size_t size, size_t align,
96 unsigned long flags, const char *name, void (*ctor)(void *));
97#ifndef CONFIG_SLOB
98struct kmem_cache *
99__kmem_cache_alias(const char *name, size_t size, size_t align,
100 unsigned long flags, void (*ctor)(void *));
101
102unsigned long kmem_cache_flags(unsigned long object_size,
103 unsigned long flags, const char *name,
104 void (*ctor)(void *));
105#else
106static inline struct kmem_cache *
107__kmem_cache_alias(const char *name, size_t size, size_t align,
108 unsigned long flags, void (*ctor)(void *))
109{ return NULL; }
110
111static inline unsigned long kmem_cache_flags(unsigned long object_size,
112 unsigned long flags, const char *name,
113 void (*ctor)(void *))
114{
115 return flags;
116}
117#endif
118
119
120/* Legal flag mask for kmem_cache_create(), for various configurations */
121#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \
122 SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS )
123
124#if defined(CONFIG_DEBUG_SLAB)
125#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
126#elif defined(CONFIG_SLUB_DEBUG)
127#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
128 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
129#else
130#define SLAB_DEBUG_FLAGS (0)
131#endif
132
133#if defined(CONFIG_SLAB)
134#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
135 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
136 SLAB_NOTRACK | SLAB_ACCOUNT)
137#elif defined(CONFIG_SLUB)
138#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
139 SLAB_TEMPORARY | SLAB_NOTRACK | SLAB_ACCOUNT)
140#else
141#define SLAB_CACHE_FLAGS (0)
142#endif
143
144#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
145
146int __kmem_cache_shutdown(struct kmem_cache *);
147void __kmem_cache_release(struct kmem_cache *);
148int __kmem_cache_shrink(struct kmem_cache *, bool);
149void slab_kmem_cache_release(struct kmem_cache *);
150
151struct seq_file;
152struct file;
153
154struct slabinfo {
155 unsigned long active_objs;
156 unsigned long num_objs;
157 unsigned long active_slabs;
158 unsigned long num_slabs;
159 unsigned long shared_avail;
160 unsigned int limit;
161 unsigned int batchcount;
162 unsigned int shared;
163 unsigned int objects_per_slab;
164 unsigned int cache_order;
165};
166
167void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
168void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
169ssize_t slabinfo_write(struct file *file, const char __user *buffer,
170 size_t count, loff_t *ppos);
171
172/*
173 * Generic implementation of bulk operations
174 * These are useful for situations in which the allocator cannot
175 * perform optimizations. In that case segments of the object listed
176 * may be allocated or freed using these operations.
177 */
178void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
179int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
180
181#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
182/*
183 * Iterate over all memcg caches of the given root cache. The caller must hold
184 * slab_mutex.
185 */
186#define for_each_memcg_cache(iter, root) \
187 list_for_each_entry(iter, &(root)->memcg_params.list, \
188 memcg_params.list)
189
190static inline bool is_root_cache(struct kmem_cache *s)
191{
192 return s->memcg_params.is_root_cache;
193}
194
195static inline bool slab_equal_or_root(struct kmem_cache *s,
196 struct kmem_cache *p)
197{
198 return p == s || p == s->memcg_params.root_cache;
199}
200
201/*
202 * We use suffixes to the name in memcg because we can't have caches
203 * created in the system with the same name. But when we print them
204 * locally, better refer to them with the base name
205 */
206static inline const char *cache_name(struct kmem_cache *s)
207{
208 if (!is_root_cache(s))
209 s = s->memcg_params.root_cache;
210 return s->name;
211}
212
213/*
214 * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
215 * That said the caller must assure the memcg's cache won't go away by either
216 * taking a css reference to the owner cgroup, or holding the slab_mutex.
217 */
218static inline struct kmem_cache *
219cache_from_memcg_idx(struct kmem_cache *s, int idx)
220{
221 struct kmem_cache *cachep;
222 struct memcg_cache_array *arr;
223
224 rcu_read_lock();
225 arr = rcu_dereference(s->memcg_params.memcg_caches);
226
227 /*
228 * Make sure we will access the up-to-date value. The code updating
229 * memcg_caches issues a write barrier to match this (see
230 * memcg_create_kmem_cache()).
231 */
232 cachep = lockless_dereference(arr->entries[idx]);
233 rcu_read_unlock();
234
235 return cachep;
236}
237
238static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
239{
240 if (is_root_cache(s))
241 return s;
242 return s->memcg_params.root_cache;
243}
244
245static __always_inline int memcg_charge_slab(struct page *page,
246 gfp_t gfp, int order,
247 struct kmem_cache *s)
248{
249 int ret;
250
251 if (!memcg_kmem_enabled())
252 return 0;
253 if (is_root_cache(s))
254 return 0;
255
256 ret = __memcg_kmem_charge_memcg(page, gfp, order,
257 s->memcg_params.memcg);
258 if (ret)
259 return ret;
260
261 memcg_kmem_update_page_stat(page,
262 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
263 MEMCG_SLAB_RECLAIMABLE : MEMCG_SLAB_UNRECLAIMABLE,
264 1 << order);
265 return 0;
266}
267
268static __always_inline void memcg_uncharge_slab(struct page *page, int order,
269 struct kmem_cache *s)
270{
271 memcg_kmem_update_page_stat(page,
272 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
273 MEMCG_SLAB_RECLAIMABLE : MEMCG_SLAB_UNRECLAIMABLE,
274 -(1 << order));
275 memcg_kmem_uncharge(page, order);
276}
277
278extern void slab_init_memcg_params(struct kmem_cache *);
279
280#else /* CONFIG_MEMCG && !CONFIG_SLOB */
281
282#define for_each_memcg_cache(iter, root) \
283 for ((void)(iter), (void)(root); 0; )
284
285static inline bool is_root_cache(struct kmem_cache *s)
286{
287 return true;
288}
289
290static inline bool slab_equal_or_root(struct kmem_cache *s,
291 struct kmem_cache *p)
292{
293 return true;
294}
295
296static inline const char *cache_name(struct kmem_cache *s)
297{
298 return s->name;
299}
300
301static inline struct kmem_cache *
302cache_from_memcg_idx(struct kmem_cache *s, int idx)
303{
304 return NULL;
305}
306
307static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
308{
309 return s;
310}
311
312static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order,
313 struct kmem_cache *s)
314{
315 return 0;
316}
317
318static inline void memcg_uncharge_slab(struct page *page, int order,
319 struct kmem_cache *s)
320{
321}
322
323static inline void slab_init_memcg_params(struct kmem_cache *s)
324{
325}
326#endif /* CONFIG_MEMCG && !CONFIG_SLOB */
327
328static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
329{
330 struct kmem_cache *cachep;
331 struct page *page;
332
333 /*
334 * When kmemcg is not being used, both assignments should return the
335 * same value. but we don't want to pay the assignment price in that
336 * case. If it is not compiled in, the compiler should be smart enough
337 * to not do even the assignment. In that case, slab_equal_or_root
338 * will also be a constant.
339 */
340 if (!memcg_kmem_enabled() &&
341 !unlikely(s->flags & SLAB_CONSISTENCY_CHECKS))
342 return s;
343
344 page = virt_to_head_page(x);
345 cachep = page->slab_cache;
346 if (slab_equal_or_root(cachep, s))
347 return cachep;
348
349 pr_err("%s: Wrong slab cache. %s but object is from %s\n",
350 __func__, s->name, cachep->name);
351 WARN_ON_ONCE(1);
352 return s;
353}
354
355static inline size_t slab_ksize(const struct kmem_cache *s)
356{
357#ifndef CONFIG_SLUB
358 return s->object_size;
359
360#else /* CONFIG_SLUB */
361# ifdef CONFIG_SLUB_DEBUG
362 /*
363 * Debugging requires use of the padding between object
364 * and whatever may come after it.
365 */
366 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
367 return s->object_size;
368# endif
369 /*
370 * If we have the need to store the freelist pointer
371 * back there or track user information then we can
372 * only use the space before that information.
373 */
374 if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
375 return s->inuse;
376 /*
377 * Else we can use all the padding etc for the allocation
378 */
379 return s->size;
380#endif
381}
382
383static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
384 gfp_t flags)
385{
386 flags &= gfp_allowed_mask;
387 lockdep_trace_alloc(flags);
388 might_sleep_if(gfpflags_allow_blocking(flags));
389
390 if (should_failslab(s, flags))
391 return NULL;
392
393 return memcg_kmem_get_cache(s, flags);
394}
395
396static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
397 size_t size, void **p)
398{
399 size_t i;
400
401 flags &= gfp_allowed_mask;
402 for (i = 0; i < size; i++) {
403 void *object = p[i];
404
405 kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
406 kmemleak_alloc_recursive(object, s->object_size, 1,
407 s->flags, flags);
408 kasan_slab_alloc(s, object, flags);
409 }
410 memcg_kmem_put_cache(s);
411}
412
413#ifndef CONFIG_SLOB
414/*
415 * The slab lists for all objects.
416 */
417struct kmem_cache_node {
418 spinlock_t list_lock;
419
420#ifdef CONFIG_SLAB
421 struct list_head slabs_partial; /* partial list first, better asm code */
422 struct list_head slabs_full;
423 struct list_head slabs_free;
424 unsigned long free_objects;
425 unsigned int free_limit;
426 unsigned int colour_next; /* Per-node cache coloring */
427 struct array_cache *shared; /* shared per node */
428 struct alien_cache **alien; /* on other nodes */
429 unsigned long next_reap; /* updated without locking */
430 int free_touched; /* updated without locking */
431#endif
432
433#ifdef CONFIG_SLUB
434 unsigned long nr_partial;
435 struct list_head partial;
436#ifdef CONFIG_SLUB_DEBUG
437 atomic_long_t nr_slabs;
438 atomic_long_t total_objects;
439 struct list_head full;
440#endif
441#endif
442
443};
444
445static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
446{
447 return s->node[node];
448}
449
450/*
451 * Iterator over all nodes. The body will be executed for each node that has
452 * a kmem_cache_node structure allocated (which is true for all online nodes)
453 */
454#define for_each_kmem_cache_node(__s, __node, __n) \
455 for (__node = 0; __node < nr_node_ids; __node++) \
456 if ((__n = get_node(__s, __node)))
457
458#endif
459
460void *slab_start(struct seq_file *m, loff_t *pos);
461void *slab_next(struct seq_file *m, void *p, loff_t *pos);
462void slab_stop(struct seq_file *m, void *p);
463int memcg_slab_show(struct seq_file *m, void *p);
464
465#endif /* MM_SLAB_H */