]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blame - mm/slab.h
UBUNTU: Ubuntu-4.15.0-96.97
[mirror_ubuntu-bionic-kernel.git] / mm / slab.h
CommitLineData
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 */
07f361b2
JK
25 const char *name; /* Slab name for sysfs */
26 int refcount; /* Use counter */
27 void (*ctor)(void *); /* Called on object slot creation */
28 struct list_head list; /* List of all slab caches on the system */
29};
30
31#endif /* CONFIG_SLOB */
32
33#ifdef CONFIG_SLAB
34#include <linux/slab_def.h>
35#endif
36
37#ifdef CONFIG_SLUB
38#include <linux/slub_def.h>
39#endif
40
41#include <linux/memcontrol.h>
11c7aec2 42#include <linux/fault-inject.h>
11c7aec2
JDB
43#include <linux/kasan.h>
44#include <linux/kmemleak.h>
7c00fce9 45#include <linux/random.h>
d92a8cfc 46#include <linux/sched/mm.h>
07f361b2 47
97d06609
CL
48/*
49 * State of the slab allocator.
50 *
51 * This is used to describe the states of the allocator during bootup.
52 * Allocators use this to gradually bootstrap themselves. Most allocators
53 * have the problem that the structures used for managing slab caches are
54 * allocated from slab caches themselves.
55 */
56enum slab_state {
57 DOWN, /* No slab functionality yet */
58 PARTIAL, /* SLUB: kmem_cache_node available */
ce8eb6c4 59 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
97d06609
CL
60 UP, /* Slab caches usable but not all extras yet */
61 FULL /* Everything is working */
62};
63
64extern enum slab_state slab_state;
65
18004c5d
CL
66/* The slab cache mutex protects the management structures during changes */
67extern struct mutex slab_mutex;
9b030cb8
CL
68
69/* The list of all slab caches on the system */
18004c5d
CL
70extern struct list_head slab_caches;
71
9b030cb8
CL
72/* The slab cache that manages slab cache information */
73extern struct kmem_cache *kmem_cache;
74
af3b5f87
VB
75/* A table of kmalloc cache names and sizes */
76extern const struct kmalloc_info_struct {
77 const char *name;
78 unsigned long size;
79} kmalloc_info[];
80
d50112ed 81unsigned long calculate_alignment(slab_flags_t flags,
45906855
CL
82 unsigned long align, unsigned long size);
83
f97d5f63
CL
84#ifndef CONFIG_SLOB
85/* Kmalloc array related functions */
34cc6990 86void setup_kmalloc_cache_index_table(void);
d50112ed 87void create_kmalloc_caches(slab_flags_t);
2c59dd65
CL
88
89/* Find the kmalloc slab corresponding for a certain size */
90struct kmem_cache *kmalloc_slab(size_t, gfp_t);
f97d5f63
CL
91#endif
92
93
9b030cb8 94/* Functions provided by the slab allocators */
d50112ed 95int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
97d06609 96
45530c44 97extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size,
d50112ed 98 slab_flags_t flags);
45530c44 99extern void create_boot_cache(struct kmem_cache *, const char *name,
d50112ed 100 size_t size, slab_flags_t flags);
45530c44 101
423c929c
JK
102int slab_unmergeable(struct kmem_cache *s);
103struct kmem_cache *find_mergeable(size_t size, size_t align,
d50112ed 104 slab_flags_t flags, const char *name, void (*ctor)(void *));
12220dea 105#ifndef CONFIG_SLOB
2633d7a0 106struct kmem_cache *
a44cb944 107__kmem_cache_alias(const char *name, size_t size, size_t align,
d50112ed 108 slab_flags_t flags, void (*ctor)(void *));
423c929c 109
d50112ed
AD
110slab_flags_t kmem_cache_flags(unsigned long object_size,
111 slab_flags_t flags, const char *name,
423c929c 112 void (*ctor)(void *));
cbb79694 113#else
2633d7a0 114static inline struct kmem_cache *
a44cb944 115__kmem_cache_alias(const char *name, size_t size, size_t align,
d50112ed 116 slab_flags_t flags, void (*ctor)(void *))
cbb79694 117{ return NULL; }
423c929c 118
d50112ed
AD
119static inline slab_flags_t kmem_cache_flags(unsigned long object_size,
120 slab_flags_t flags, const char *name,
423c929c
JK
121 void (*ctor)(void *))
122{
123 return flags;
124}
cbb79694
CL
125#endif
126
127
d8843922 128/* Legal flag mask for kmem_cache_create(), for various configurations */
26f42db9
NB
129#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
130 SLAB_CACHE_DMA32 | SLAB_PANIC | \
5f0d5a3a 131 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
d8843922
GC
132
133#if defined(CONFIG_DEBUG_SLAB)
134#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
135#elif defined(CONFIG_SLUB_DEBUG)
136#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
becfda68 137 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
d8843922
GC
138#else
139#define SLAB_DEBUG_FLAGS (0)
140#endif
141
142#if defined(CONFIG_SLAB)
143#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
230e9fc2 144 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
75f296d9 145 SLAB_ACCOUNT)
d8843922
GC
146#elif defined(CONFIG_SLUB)
147#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
75f296d9 148 SLAB_TEMPORARY | SLAB_ACCOUNT)
d8843922
GC
149#else
150#define SLAB_CACHE_FLAGS (0)
151#endif
152
e70954fd 153/* Common flags available with current configuration */
d8843922
GC
154#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
155
e70954fd
TG
156/* Common flags permitted for kmem_cache_create */
157#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
158 SLAB_RED_ZONE | \
159 SLAB_POISON | \
160 SLAB_STORE_USER | \
161 SLAB_TRACE | \
162 SLAB_CONSISTENCY_CHECKS | \
163 SLAB_MEM_SPREAD | \
164 SLAB_NOLEAKTRACE | \
165 SLAB_RECLAIM_ACCOUNT | \
166 SLAB_TEMPORARY | \
e70954fd
TG
167 SLAB_ACCOUNT)
168
945cf2b6 169int __kmem_cache_shutdown(struct kmem_cache *);
52b4b950 170void __kmem_cache_release(struct kmem_cache *);
c9fc5864
TH
171int __kmem_cache_shrink(struct kmem_cache *);
172void __kmemcg_cache_deactivate(struct kmem_cache *s);
41a21285 173void slab_kmem_cache_release(struct kmem_cache *);
945cf2b6 174
b7454ad3
GC
175struct seq_file;
176struct file;
b7454ad3 177
0d7561c6
GC
178struct slabinfo {
179 unsigned long active_objs;
180 unsigned long num_objs;
181 unsigned long active_slabs;
182 unsigned long num_slabs;
183 unsigned long shared_avail;
184 unsigned int limit;
185 unsigned int batchcount;
186 unsigned int shared;
187 unsigned int objects_per_slab;
188 unsigned int cache_order;
189};
190
191void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
192void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
b7454ad3
GC
193ssize_t slabinfo_write(struct file *file, const char __user *buffer,
194 size_t count, loff_t *ppos);
ba6c496e 195
484748f0
CL
196/*
197 * Generic implementation of bulk operations
198 * These are useful for situations in which the allocator cannot
9f706d68 199 * perform optimizations. In that case segments of the object listed
484748f0
CL
200 * may be allocated or freed using these operations.
201 */
202void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
865762a8 203int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
484748f0 204
127424c8 205#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
510ded33
TH
206
207/* List of all root caches. */
208extern struct list_head slab_root_caches;
209#define root_caches_node memcg_params.__root_caches_node
210
426589f5
VD
211/*
212 * Iterate over all memcg caches of the given root cache. The caller must hold
213 * slab_mutex.
214 */
215#define for_each_memcg_cache(iter, root) \
9eeadc8b
TH
216 list_for_each_entry(iter, &(root)->memcg_params.children, \
217 memcg_params.children_node)
426589f5 218
ba6c496e
GC
219static inline bool is_root_cache(struct kmem_cache *s)
220{
9eeadc8b 221 return !s->memcg_params.root_cache;
ba6c496e 222}
2633d7a0 223
b9ce5ef4 224static inline bool slab_equal_or_root(struct kmem_cache *s,
f7ce3190 225 struct kmem_cache *p)
b9ce5ef4 226{
f7ce3190 227 return p == s || p == s->memcg_params.root_cache;
b9ce5ef4 228}
749c5415
GC
229
230/*
231 * We use suffixes to the name in memcg because we can't have caches
232 * created in the system with the same name. But when we print them
233 * locally, better refer to them with the base name
234 */
235static inline const char *cache_name(struct kmem_cache *s)
236{
237 if (!is_root_cache(s))
f7ce3190 238 s = s->memcg_params.root_cache;
749c5415
GC
239 return s->name;
240}
241
f8570263
VD
242/*
243 * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
f7ce3190
VD
244 * That said the caller must assure the memcg's cache won't go away by either
245 * taking a css reference to the owner cgroup, or holding the slab_mutex.
f8570263 246 */
2ade4de8
QH
247static inline struct kmem_cache *
248cache_from_memcg_idx(struct kmem_cache *s, int idx)
749c5415 249{
959c8963 250 struct kmem_cache *cachep;
f7ce3190 251 struct memcg_cache_array *arr;
f8570263
VD
252
253 rcu_read_lock();
f7ce3190 254 arr = rcu_dereference(s->memcg_params.memcg_caches);
959c8963
VD
255
256 /*
257 * Make sure we will access the up-to-date value. The code updating
258 * memcg_caches issues a write barrier to match this (see
f7ce3190 259 * memcg_create_kmem_cache()).
959c8963 260 */
506458ef 261 cachep = READ_ONCE(arr->entries[idx]);
8df0c2dc
PK
262 rcu_read_unlock();
263
959c8963 264 return cachep;
749c5415 265}
943a451a
GC
266
267static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
268{
269 if (is_root_cache(s))
270 return s;
f7ce3190 271 return s->memcg_params.root_cache;
943a451a 272}
5dfb4175 273
f3ccb2c4
VD
274static __always_inline int memcg_charge_slab(struct page *page,
275 gfp_t gfp, int order,
276 struct kmem_cache *s)
5dfb4175
VD
277{
278 if (!memcg_kmem_enabled())
279 return 0;
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{
45264778
VD
288 if (!memcg_kmem_enabled())
289 return;
27ee57c9 290 memcg_kmem_uncharge(page, order);
5dfb4175 291}
f7ce3190
VD
292
293extern void slab_init_memcg_params(struct kmem_cache *);
510ded33 294extern void memcg_link_cache(struct kmem_cache *s);
01fb58bc
TH
295extern void slab_deactivate_memcg_cache_rcu_sched(struct kmem_cache *s,
296 void (*deact_fn)(struct kmem_cache *));
f7ce3190 297
127424c8 298#else /* CONFIG_MEMCG && !CONFIG_SLOB */
f7ce3190 299
510ded33
TH
300/* If !memcg, all caches are root. */
301#define slab_root_caches slab_caches
302#define root_caches_node list
303
426589f5
VD
304#define for_each_memcg_cache(iter, root) \
305 for ((void)(iter), (void)(root); 0; )
426589f5 306
ba6c496e
GC
307static inline bool is_root_cache(struct kmem_cache *s)
308{
309 return true;
310}
311
b9ce5ef4
GC
312static inline bool slab_equal_or_root(struct kmem_cache *s,
313 struct kmem_cache *p)
314{
315 return true;
316}
749c5415
GC
317
318static inline const char *cache_name(struct kmem_cache *s)
319{
320 return s->name;
321}
322
2ade4de8
QH
323static inline struct kmem_cache *
324cache_from_memcg_idx(struct kmem_cache *s, int idx)
749c5415
GC
325{
326 return NULL;
327}
943a451a
GC
328
329static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
330{
331 return s;
332}
5dfb4175 333
f3ccb2c4
VD
334static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order,
335 struct kmem_cache *s)
5dfb4175
VD
336{
337 return 0;
338}
339
27ee57c9
VD
340static inline void memcg_uncharge_slab(struct page *page, int order,
341 struct kmem_cache *s)
342{
343}
344
f7ce3190
VD
345static inline void slab_init_memcg_params(struct kmem_cache *s)
346{
347}
510ded33
TH
348
349static inline void memcg_link_cache(struct kmem_cache *s)
350{
351}
352
127424c8 353#endif /* CONFIG_MEMCG && !CONFIG_SLOB */
b9ce5ef4
GC
354
355static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
356{
357 struct kmem_cache *cachep;
358 struct page *page;
359
360 /*
361 * When kmemcg is not being used, both assignments should return the
362 * same value. but we don't want to pay the assignment price in that
363 * case. If it is not compiled in, the compiler should be smart enough
364 * to not do even the assignment. In that case, slab_equal_or_root
365 * will also be a constant.
366 */
becfda68
LA
367 if (!memcg_kmem_enabled() &&
368 !unlikely(s->flags & SLAB_CONSISTENCY_CHECKS))
b9ce5ef4
GC
369 return s;
370
371 page = virt_to_head_page(x);
372 cachep = page->slab_cache;
373 if (slab_equal_or_root(cachep, s))
374 return cachep;
375
376 pr_err("%s: Wrong slab cache. %s but object is from %s\n",
2d16e0fd 377 __func__, s->name, cachep->name);
b9ce5ef4
GC
378 WARN_ON_ONCE(1);
379 return s;
380}
ca34956b 381
11c7aec2
JDB
382static inline size_t slab_ksize(const struct kmem_cache *s)
383{
384#ifndef CONFIG_SLUB
385 return s->object_size;
386
387#else /* CONFIG_SLUB */
388# ifdef CONFIG_SLUB_DEBUG
389 /*
390 * Debugging requires use of the padding between object
391 * and whatever may come after it.
392 */
393 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
394 return s->object_size;
395# endif
80a9201a
AP
396 if (s->flags & SLAB_KASAN)
397 return s->object_size;
11c7aec2
JDB
398 /*
399 * If we have the need to store the freelist pointer
400 * back there or track user information then we can
401 * only use the space before that information.
402 */
5f0d5a3a 403 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
11c7aec2
JDB
404 return s->inuse;
405 /*
406 * Else we can use all the padding etc for the allocation
407 */
408 return s->size;
409#endif
410}
411
412static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
413 gfp_t flags)
414{
415 flags &= gfp_allowed_mask;
d92a8cfc
PZ
416
417 fs_reclaim_acquire(flags);
418 fs_reclaim_release(flags);
419
11c7aec2
JDB
420 might_sleep_if(gfpflags_allow_blocking(flags));
421
fab9963a 422 if (should_failslab(s, flags))
11c7aec2
JDB
423 return NULL;
424
45264778
VD
425 if (memcg_kmem_enabled() &&
426 ((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT)))
427 return memcg_kmem_get_cache(s);
428
429 return s;
11c7aec2
JDB
430}
431
432static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
433 size_t size, void **p)
434{
435 size_t i;
436
437 flags &= gfp_allowed_mask;
438 for (i = 0; i < size; i++) {
439 void *object = p[i];
440
11c7aec2
JDB
441 kmemleak_alloc_recursive(object, s->object_size, 1,
442 s->flags, flags);
505f5dcb 443 kasan_slab_alloc(s, object, flags);
11c7aec2 444 }
45264778
VD
445
446 if (memcg_kmem_enabled())
447 memcg_kmem_put_cache(s);
11c7aec2
JDB
448}
449
44c5356f 450#ifndef CONFIG_SLOB
ca34956b
CL
451/*
452 * The slab lists for all objects.
453 */
454struct kmem_cache_node {
455 spinlock_t list_lock;
456
457#ifdef CONFIG_SLAB
458 struct list_head slabs_partial; /* partial list first, better asm code */
459 struct list_head slabs_full;
460 struct list_head slabs_free;
bf00bd34
DR
461 unsigned long total_slabs; /* length of all slab lists */
462 unsigned long free_slabs; /* length of free slab list only */
ca34956b
CL
463 unsigned long free_objects;
464 unsigned int free_limit;
465 unsigned int colour_next; /* Per-node cache coloring */
466 struct array_cache *shared; /* shared per node */
c8522a3a 467 struct alien_cache **alien; /* on other nodes */
ca34956b
CL
468 unsigned long next_reap; /* updated without locking */
469 int free_touched; /* updated without locking */
470#endif
471
472#ifdef CONFIG_SLUB
473 unsigned long nr_partial;
474 struct list_head partial;
475#ifdef CONFIG_SLUB_DEBUG
476 atomic_long_t nr_slabs;
477 atomic_long_t total_objects;
478 struct list_head full;
479#endif
480#endif
481
482};
e25839f6 483
44c5356f
CL
484static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
485{
486 return s->node[node];
487}
488
489/*
490 * Iterator over all nodes. The body will be executed for each node that has
491 * a kmem_cache_node structure allocated (which is true for all online nodes)
492 */
493#define for_each_kmem_cache_node(__s, __node, __n) \
9163582c
MP
494 for (__node = 0; __node < nr_node_ids; __node++) \
495 if ((__n = get_node(__s, __node)))
44c5356f
CL
496
497#endif
498
1df3b26f 499void *slab_start(struct seq_file *m, loff_t *pos);
276a2439
WL
500void *slab_next(struct seq_file *m, void *p, loff_t *pos);
501void slab_stop(struct seq_file *m, void *p);
bc2791f8
TH
502void *memcg_slab_start(struct seq_file *m, loff_t *pos);
503void *memcg_slab_next(struct seq_file *m, void *p, loff_t *pos);
504void memcg_slab_stop(struct seq_file *m, void *p);
b047501c 505int memcg_slab_show(struct seq_file *m, void *p);
5240ab40 506
852d8be0
YS
507#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
508void dump_unreclaimable_slab(void);
509#else
510static inline void dump_unreclaimable_slab(void)
511{
512}
513#endif
514
55834c59
AP
515void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
516
7c00fce9
TG
517#ifdef CONFIG_SLAB_FREELIST_RANDOM
518int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
519 gfp_t gfp);
520void cache_random_seq_destroy(struct kmem_cache *cachep);
521#else
522static inline int cache_random_seq_create(struct kmem_cache *cachep,
523 unsigned int count, gfp_t gfp)
524{
525 return 0;
526}
527static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
528#endif /* CONFIG_SLAB_FREELIST_RANDOM */
529
5240ab40 530#endif /* MM_SLAB_H */