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b2441318 1/* SPDX-License-Identifier: GPL-2.0 */
97d06609
CL
2#ifndef MM_SLAB_H
3#define MM_SLAB_H
4/*
5 * Internal slab definitions
6 */
7
07f361b2
JK
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 */
d50112ed 24 slab_flags_t flags; /* Active flags on the slab */
7bbdb81e
AD
25 unsigned int useroffset;/* Usercopy region offset */
26 unsigned int usersize; /* Usercopy region size */
07f361b2
JK
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>
11c7aec2 44#include <linux/fault-inject.h>
11c7aec2
JDB
45#include <linux/kasan.h>
46#include <linux/kmemleak.h>
7c00fce9 47#include <linux/random.h>
d92a8cfc 48#include <linux/sched/mm.h>
07f361b2 49
97d06609
CL
50/*
51 * State of the slab allocator.
52 *
53 * This is used to describe the states of the allocator during bootup.
54 * Allocators use this to gradually bootstrap themselves. Most allocators
55 * have the problem that the structures used for managing slab caches are
56 * allocated from slab caches themselves.
57 */
58enum slab_state {
59 DOWN, /* No slab functionality yet */
60 PARTIAL, /* SLUB: kmem_cache_node available */
ce8eb6c4 61 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
97d06609
CL
62 UP, /* Slab caches usable but not all extras yet */
63 FULL /* Everything is working */
64};
65
66extern enum slab_state slab_state;
67
18004c5d
CL
68/* The slab cache mutex protects the management structures during changes */
69extern struct mutex slab_mutex;
9b030cb8
CL
70
71/* The list of all slab caches on the system */
18004c5d
CL
72extern struct list_head slab_caches;
73
9b030cb8
CL
74/* The slab cache that manages slab cache information */
75extern struct kmem_cache *kmem_cache;
76
af3b5f87
VB
77/* A table of kmalloc cache names and sizes */
78extern const struct kmalloc_info_struct {
79 const char *name;
55de8b9c 80 unsigned int size;
af3b5f87
VB
81} kmalloc_info[];
82
f97d5f63
CL
83#ifndef CONFIG_SLOB
84/* Kmalloc array related functions */
34cc6990 85void setup_kmalloc_cache_index_table(void);
d50112ed 86void create_kmalloc_caches(slab_flags_t);
2c59dd65
CL
87
88/* Find the kmalloc slab corresponding for a certain size */
89struct kmem_cache *kmalloc_slab(size_t, gfp_t);
f97d5f63
CL
90#endif
91
92
9b030cb8 93/* Functions provided by the slab allocators */
d50112ed 94int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
97d06609 95
55de8b9c
AD
96struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size,
97 slab_flags_t flags, unsigned int useroffset,
98 unsigned int usersize);
45530c44 99extern void create_boot_cache(struct kmem_cache *, const char *name,
361d575e
AD
100 unsigned int size, slab_flags_t flags,
101 unsigned int useroffset, unsigned int usersize);
45530c44 102
423c929c 103int slab_unmergeable(struct kmem_cache *s);
f4957d5b 104struct kmem_cache *find_mergeable(unsigned size, unsigned align,
d50112ed 105 slab_flags_t flags, const char *name, void (*ctor)(void *));
12220dea 106#ifndef CONFIG_SLOB
2633d7a0 107struct kmem_cache *
f4957d5b 108__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
d50112ed 109 slab_flags_t flags, void (*ctor)(void *));
423c929c 110
0293d1fd 111slab_flags_t kmem_cache_flags(unsigned int object_size,
d50112ed 112 slab_flags_t flags, const char *name,
423c929c 113 void (*ctor)(void *));
cbb79694 114#else
2633d7a0 115static inline struct kmem_cache *
f4957d5b 116__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
d50112ed 117 slab_flags_t flags, void (*ctor)(void *))
cbb79694 118{ return NULL; }
423c929c 119
0293d1fd 120static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
d50112ed 121 slab_flags_t flags, const char *name,
423c929c
JK
122 void (*ctor)(void *))
123{
124 return flags;
125}
cbb79694
CL
126#endif
127
128
d8843922 129/* Legal flag mask for kmem_cache_create(), for various configurations */
6d6ea1e9
NB
130#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
131 SLAB_CACHE_DMA32 | SLAB_PANIC | \
5f0d5a3a 132 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
d8843922
GC
133
134#if defined(CONFIG_DEBUG_SLAB)
135#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
136#elif defined(CONFIG_SLUB_DEBUG)
137#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
becfda68 138 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
d8843922
GC
139#else
140#define SLAB_DEBUG_FLAGS (0)
141#endif
142
143#if defined(CONFIG_SLAB)
144#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
230e9fc2 145 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
75f296d9 146 SLAB_ACCOUNT)
d8843922
GC
147#elif defined(CONFIG_SLUB)
148#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
75f296d9 149 SLAB_TEMPORARY | SLAB_ACCOUNT)
d8843922
GC
150#else
151#define SLAB_CACHE_FLAGS (0)
152#endif
153
e70954fd 154/* Common flags available with current configuration */
d8843922
GC
155#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
156
e70954fd
TG
157/* Common flags permitted for kmem_cache_create */
158#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
159 SLAB_RED_ZONE | \
160 SLAB_POISON | \
161 SLAB_STORE_USER | \
162 SLAB_TRACE | \
163 SLAB_CONSISTENCY_CHECKS | \
164 SLAB_MEM_SPREAD | \
165 SLAB_NOLEAKTRACE | \
166 SLAB_RECLAIM_ACCOUNT | \
167 SLAB_TEMPORARY | \
e70954fd
TG
168 SLAB_ACCOUNT)
169
f9e13c0a 170bool __kmem_cache_empty(struct kmem_cache *);
945cf2b6 171int __kmem_cache_shutdown(struct kmem_cache *);
52b4b950 172void __kmem_cache_release(struct kmem_cache *);
c9fc5864
TH
173int __kmem_cache_shrink(struct kmem_cache *);
174void __kmemcg_cache_deactivate(struct kmem_cache *s);
41a21285 175void slab_kmem_cache_release(struct kmem_cache *);
945cf2b6 176
b7454ad3
GC
177struct seq_file;
178struct file;
b7454ad3 179
0d7561c6
GC
180struct slabinfo {
181 unsigned long active_objs;
182 unsigned long num_objs;
183 unsigned long active_slabs;
184 unsigned long num_slabs;
185 unsigned long shared_avail;
186 unsigned int limit;
187 unsigned int batchcount;
188 unsigned int shared;
189 unsigned int objects_per_slab;
190 unsigned int cache_order;
191};
192
193void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
194void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
b7454ad3
GC
195ssize_t slabinfo_write(struct file *file, const char __user *buffer,
196 size_t count, loff_t *ppos);
ba6c496e 197
484748f0
CL
198/*
199 * Generic implementation of bulk operations
200 * These are useful for situations in which the allocator cannot
9f706d68 201 * perform optimizations. In that case segments of the object listed
484748f0
CL
202 * may be allocated or freed using these operations.
203 */
204void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
865762a8 205int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
484748f0 206
84c07d11 207#ifdef CONFIG_MEMCG_KMEM
510ded33
TH
208
209/* List of all root caches. */
210extern struct list_head slab_root_caches;
211#define root_caches_node memcg_params.__root_caches_node
212
426589f5
VD
213/*
214 * Iterate over all memcg caches of the given root cache. The caller must hold
215 * slab_mutex.
216 */
217#define for_each_memcg_cache(iter, root) \
9eeadc8b
TH
218 list_for_each_entry(iter, &(root)->memcg_params.children, \
219 memcg_params.children_node)
426589f5 220
ba6c496e
GC
221static inline bool is_root_cache(struct kmem_cache *s)
222{
9eeadc8b 223 return !s->memcg_params.root_cache;
ba6c496e 224}
2633d7a0 225
b9ce5ef4 226static inline bool slab_equal_or_root(struct kmem_cache *s,
f7ce3190 227 struct kmem_cache *p)
b9ce5ef4 228{
f7ce3190 229 return p == s || p == s->memcg_params.root_cache;
b9ce5ef4 230}
749c5415
GC
231
232/*
233 * We use suffixes to the name in memcg because we can't have caches
234 * created in the system with the same name. But when we print them
235 * locally, better refer to them with the base name
236 */
237static inline const char *cache_name(struct kmem_cache *s)
238{
239 if (!is_root_cache(s))
f7ce3190 240 s = s->memcg_params.root_cache;
749c5415
GC
241 return s->name;
242}
243
f8570263
VD
244/*
245 * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
f7ce3190
VD
246 * That said the caller must assure the memcg's cache won't go away by either
247 * taking a css reference to the owner cgroup, or holding the slab_mutex.
f8570263 248 */
2ade4de8
QH
249static inline struct kmem_cache *
250cache_from_memcg_idx(struct kmem_cache *s, int idx)
749c5415 251{
959c8963 252 struct kmem_cache *cachep;
f7ce3190 253 struct memcg_cache_array *arr;
f8570263
VD
254
255 rcu_read_lock();
f7ce3190 256 arr = rcu_dereference(s->memcg_params.memcg_caches);
959c8963
VD
257
258 /*
259 * Make sure we will access the up-to-date value. The code updating
260 * memcg_caches issues a write barrier to match this (see
f7ce3190 261 * memcg_create_kmem_cache()).
959c8963 262 */
506458ef 263 cachep = READ_ONCE(arr->entries[idx]);
8df0c2dc
PK
264 rcu_read_unlock();
265
959c8963 266 return cachep;
749c5415 267}
943a451a
GC
268
269static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
270{
271 if (is_root_cache(s))
272 return s;
f7ce3190 273 return s->memcg_params.root_cache;
943a451a 274}
5dfb4175 275
f3ccb2c4
VD
276static __always_inline int memcg_charge_slab(struct page *page,
277 gfp_t gfp, int order,
278 struct kmem_cache *s)
5dfb4175 279{
5dfb4175
VD
280 if (is_root_cache(s))
281 return 0;
7779f212 282 return memcg_kmem_charge_memcg(page, gfp, order, s->memcg_params.memcg);
27ee57c9
VD
283}
284
285static __always_inline void memcg_uncharge_slab(struct page *page, int order,
286 struct kmem_cache *s)
287{
27ee57c9 288 memcg_kmem_uncharge(page, order);
5dfb4175 289}
f7ce3190
VD
290
291extern void slab_init_memcg_params(struct kmem_cache *);
510ded33 292extern void memcg_link_cache(struct kmem_cache *s);
01fb58bc
TH
293extern void slab_deactivate_memcg_cache_rcu_sched(struct kmem_cache *s,
294 void (*deact_fn)(struct kmem_cache *));
f7ce3190 295
84c07d11 296#else /* CONFIG_MEMCG_KMEM */
f7ce3190 297
510ded33
TH
298/* If !memcg, all caches are root. */
299#define slab_root_caches slab_caches
300#define root_caches_node list
301
426589f5
VD
302#define for_each_memcg_cache(iter, root) \
303 for ((void)(iter), (void)(root); 0; )
426589f5 304
ba6c496e
GC
305static inline bool is_root_cache(struct kmem_cache *s)
306{
307 return true;
308}
309
b9ce5ef4
GC
310static inline bool slab_equal_or_root(struct kmem_cache *s,
311 struct kmem_cache *p)
312{
313 return true;
314}
749c5415
GC
315
316static inline const char *cache_name(struct kmem_cache *s)
317{
318 return s->name;
319}
320
2ade4de8
QH
321static inline struct kmem_cache *
322cache_from_memcg_idx(struct kmem_cache *s, int idx)
749c5415
GC
323{
324 return NULL;
325}
943a451a
GC
326
327static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
328{
329 return s;
330}
5dfb4175 331
f3ccb2c4
VD
332static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order,
333 struct kmem_cache *s)
5dfb4175
VD
334{
335 return 0;
336}
337
27ee57c9
VD
338static inline void memcg_uncharge_slab(struct page *page, int order,
339 struct kmem_cache *s)
340{
341}
342
f7ce3190
VD
343static inline void slab_init_memcg_params(struct kmem_cache *s)
344{
345}
510ded33
TH
346
347static inline void memcg_link_cache(struct kmem_cache *s)
348{
349}
350
84c07d11 351#endif /* CONFIG_MEMCG_KMEM */
b9ce5ef4
GC
352
353static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
354{
355 struct kmem_cache *cachep;
356 struct page *page;
357
358 /*
359 * When kmemcg is not being used, both assignments should return the
360 * same value. but we don't want to pay the assignment price in that
361 * case. If it is not compiled in, the compiler should be smart enough
362 * to not do even the assignment. In that case, slab_equal_or_root
363 * will also be a constant.
364 */
becfda68
LA
365 if (!memcg_kmem_enabled() &&
366 !unlikely(s->flags & SLAB_CONSISTENCY_CHECKS))
b9ce5ef4
GC
367 return s;
368
369 page = virt_to_head_page(x);
370 cachep = page->slab_cache;
371 if (slab_equal_or_root(cachep, s))
372 return cachep;
373
374 pr_err("%s: Wrong slab cache. %s but object is from %s\n",
2d16e0fd 375 __func__, s->name, cachep->name);
b9ce5ef4
GC
376 WARN_ON_ONCE(1);
377 return s;
378}
ca34956b 379
11c7aec2
JDB
380static inline size_t slab_ksize(const struct kmem_cache *s)
381{
382#ifndef CONFIG_SLUB
383 return s->object_size;
384
385#else /* CONFIG_SLUB */
386# ifdef CONFIG_SLUB_DEBUG
387 /*
388 * Debugging requires use of the padding between object
389 * and whatever may come after it.
390 */
391 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
392 return s->object_size;
393# endif
80a9201a
AP
394 if (s->flags & SLAB_KASAN)
395 return s->object_size;
11c7aec2
JDB
396 /*
397 * If we have the need to store the freelist pointer
398 * back there or track user information then we can
399 * only use the space before that information.
400 */
5f0d5a3a 401 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
11c7aec2
JDB
402 return s->inuse;
403 /*
404 * Else we can use all the padding etc for the allocation
405 */
406 return s->size;
407#endif
408}
409
410static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
411 gfp_t flags)
412{
413 flags &= gfp_allowed_mask;
d92a8cfc
PZ
414
415 fs_reclaim_acquire(flags);
416 fs_reclaim_release(flags);
417
11c7aec2
JDB
418 might_sleep_if(gfpflags_allow_blocking(flags));
419
fab9963a 420 if (should_failslab(s, flags))
11c7aec2
JDB
421 return NULL;
422
45264778
VD
423 if (memcg_kmem_enabled() &&
424 ((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT)))
425 return memcg_kmem_get_cache(s);
426
427 return s;
11c7aec2
JDB
428}
429
430static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
431 size_t size, void **p)
432{
433 size_t i;
434
435 flags &= gfp_allowed_mask;
436 for (i = 0; i < size; i++) {
53128245 437 p[i] = kasan_slab_alloc(s, p[i], flags);
a2f77575 438 /* As p[i] might get tagged, call kmemleak hook after KASAN. */
53128245 439 kmemleak_alloc_recursive(p[i], s->object_size, 1,
11c7aec2 440 s->flags, flags);
11c7aec2 441 }
45264778
VD
442
443 if (memcg_kmem_enabled())
444 memcg_kmem_put_cache(s);
11c7aec2
JDB
445}
446
44c5356f 447#ifndef CONFIG_SLOB
ca34956b
CL
448/*
449 * The slab lists for all objects.
450 */
451struct kmem_cache_node {
452 spinlock_t list_lock;
453
454#ifdef CONFIG_SLAB
455 struct list_head slabs_partial; /* partial list first, better asm code */
456 struct list_head slabs_full;
457 struct list_head slabs_free;
bf00bd34
DR
458 unsigned long total_slabs; /* length of all slab lists */
459 unsigned long free_slabs; /* length of free slab list only */
ca34956b
CL
460 unsigned long free_objects;
461 unsigned int free_limit;
462 unsigned int colour_next; /* Per-node cache coloring */
463 struct array_cache *shared; /* shared per node */
c8522a3a 464 struct alien_cache **alien; /* on other nodes */
ca34956b
CL
465 unsigned long next_reap; /* updated without locking */
466 int free_touched; /* updated without locking */
467#endif
468
469#ifdef CONFIG_SLUB
470 unsigned long nr_partial;
471 struct list_head partial;
472#ifdef CONFIG_SLUB_DEBUG
473 atomic_long_t nr_slabs;
474 atomic_long_t total_objects;
475 struct list_head full;
476#endif
477#endif
478
479};
e25839f6 480
44c5356f
CL
481static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
482{
483 return s->node[node];
484}
485
486/*
487 * Iterator over all nodes. The body will be executed for each node that has
488 * a kmem_cache_node structure allocated (which is true for all online nodes)
489 */
490#define for_each_kmem_cache_node(__s, __node, __n) \
9163582c
MP
491 for (__node = 0; __node < nr_node_ids; __node++) \
492 if ((__n = get_node(__s, __node)))
44c5356f
CL
493
494#endif
495
1df3b26f 496void *slab_start(struct seq_file *m, loff_t *pos);
276a2439
WL
497void *slab_next(struct seq_file *m, void *p, loff_t *pos);
498void slab_stop(struct seq_file *m, void *p);
bc2791f8
TH
499void *memcg_slab_start(struct seq_file *m, loff_t *pos);
500void *memcg_slab_next(struct seq_file *m, void *p, loff_t *pos);
501void memcg_slab_stop(struct seq_file *m, void *p);
b047501c 502int memcg_slab_show(struct seq_file *m, void *p);
5240ab40 503
852d8be0
YS
504#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
505void dump_unreclaimable_slab(void);
506#else
507static inline void dump_unreclaimable_slab(void)
508{
509}
510#endif
511
55834c59
AP
512void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
513
7c00fce9
TG
514#ifdef CONFIG_SLAB_FREELIST_RANDOM
515int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
516 gfp_t gfp);
517void cache_random_seq_destroy(struct kmem_cache *cachep);
518#else
519static inline int cache_random_seq_create(struct kmem_cache *cachep,
520 unsigned int count, gfp_t gfp)
521{
522 return 0;
523}
524static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
525#endif /* CONFIG_SLAB_FREELIST_RANDOM */
526
5240ab40 527#endif /* MM_SLAB_H */