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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 /* Reuses the bits in struct page */
9 struct slab {
10 unsigned long __page_flags;
11
12 #if defined(CONFIG_SLAB)
13
14 union {
15 struct list_head slab_list;
16 struct rcu_head rcu_head;
17 };
18 struct kmem_cache *slab_cache;
19 void *freelist; /* array of free object indexes */
20 void *s_mem; /* first object */
21 unsigned int active;
22
23 #elif defined(CONFIG_SLUB)
24
25 union {
26 struct list_head slab_list;
27 struct rcu_head rcu_head;
28 #ifdef CONFIG_SLUB_CPU_PARTIAL
29 struct {
30 struct slab *next;
31 int slabs; /* Nr of slabs left */
32 };
33 #endif
34 };
35 struct kmem_cache *slab_cache;
36 /* Double-word boundary */
37 void *freelist; /* first free object */
38 union {
39 unsigned long counters;
40 struct {
41 unsigned inuse:16;
42 unsigned objects:15;
43 unsigned frozen:1;
44 };
45 };
46 unsigned int __unused;
47
48 #elif defined(CONFIG_SLOB)
49
50 struct list_head slab_list;
51 void *__unused_1;
52 void *freelist; /* first free block */
53 long units;
54 unsigned int __unused_2;
55
56 #else
57 #error "Unexpected slab allocator configured"
58 #endif
59
60 atomic_t __page_refcount;
61 #ifdef CONFIG_MEMCG
62 unsigned long memcg_data;
63 #endif
64 };
65
66 #define SLAB_MATCH(pg, sl) \
67 static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl))
68 SLAB_MATCH(flags, __page_flags);
69 SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */
70 #ifndef CONFIG_SLOB
71 SLAB_MATCH(rcu_head, rcu_head);
72 #endif
73 SLAB_MATCH(_refcount, __page_refcount);
74 #ifdef CONFIG_MEMCG
75 SLAB_MATCH(memcg_data, memcg_data);
76 #endif
77 #undef SLAB_MATCH
78 static_assert(sizeof(struct slab) <= sizeof(struct page));
79
80 /**
81 * folio_slab - Converts from folio to slab.
82 * @folio: The folio.
83 *
84 * Currently struct slab is a different representation of a folio where
85 * folio_test_slab() is true.
86 *
87 * Return: The slab which contains this folio.
88 */
89 #define folio_slab(folio) (_Generic((folio), \
90 const struct folio *: (const struct slab *)(folio), \
91 struct folio *: (struct slab *)(folio)))
92
93 /**
94 * slab_folio - The folio allocated for a slab
95 * @slab: The slab.
96 *
97 * Slabs are allocated as folios that contain the individual objects and are
98 * using some fields in the first struct page of the folio - those fields are
99 * now accessed by struct slab. It is occasionally necessary to convert back to
100 * a folio in order to communicate with the rest of the mm. Please use this
101 * helper function instead of casting yourself, as the implementation may change
102 * in the future.
103 */
104 #define slab_folio(s) (_Generic((s), \
105 const struct slab *: (const struct folio *)s, \
106 struct slab *: (struct folio *)s))
107
108 /**
109 * page_slab - Converts from first struct page to slab.
110 * @p: The first (either head of compound or single) page of slab.
111 *
112 * A temporary wrapper to convert struct page to struct slab in situations where
113 * we know the page is the compound head, or single order-0 page.
114 *
115 * Long-term ideally everything would work with struct slab directly or go
116 * through folio to struct slab.
117 *
118 * Return: The slab which contains this page
119 */
120 #define page_slab(p) (_Generic((p), \
121 const struct page *: (const struct slab *)(p), \
122 struct page *: (struct slab *)(p)))
123
124 /**
125 * slab_page - The first struct page allocated for a slab
126 * @slab: The slab.
127 *
128 * A convenience wrapper for converting slab to the first struct page of the
129 * underlying folio, to communicate with code not yet converted to folio or
130 * struct slab.
131 */
132 #define slab_page(s) folio_page(slab_folio(s), 0)
133
134 /*
135 * If network-based swap is enabled, sl*b must keep track of whether pages
136 * were allocated from pfmemalloc reserves.
137 */
138 static inline bool slab_test_pfmemalloc(const struct slab *slab)
139 {
140 return folio_test_active((struct folio *)slab_folio(slab));
141 }
142
143 static inline void slab_set_pfmemalloc(struct slab *slab)
144 {
145 folio_set_active(slab_folio(slab));
146 }
147
148 static inline void slab_clear_pfmemalloc(struct slab *slab)
149 {
150 folio_clear_active(slab_folio(slab));
151 }
152
153 static inline void __slab_clear_pfmemalloc(struct slab *slab)
154 {
155 __folio_clear_active(slab_folio(slab));
156 }
157
158 static inline void *slab_address(const struct slab *slab)
159 {
160 return folio_address(slab_folio(slab));
161 }
162
163 static inline int slab_nid(const struct slab *slab)
164 {
165 return folio_nid(slab_folio(slab));
166 }
167
168 static inline pg_data_t *slab_pgdat(const struct slab *slab)
169 {
170 return folio_pgdat(slab_folio(slab));
171 }
172
173 static inline struct slab *virt_to_slab(const void *addr)
174 {
175 struct folio *folio = virt_to_folio(addr);
176
177 if (!folio_test_slab(folio))
178 return NULL;
179
180 return folio_slab(folio);
181 }
182
183 static inline int slab_order(const struct slab *slab)
184 {
185 return folio_order((struct folio *)slab_folio(slab));
186 }
187
188 static inline size_t slab_size(const struct slab *slab)
189 {
190 return PAGE_SIZE << slab_order(slab);
191 }
192
193 #ifdef CONFIG_SLOB
194 /*
195 * Common fields provided in kmem_cache by all slab allocators
196 * This struct is either used directly by the allocator (SLOB)
197 * or the allocator must include definitions for all fields
198 * provided in kmem_cache_common in their definition of kmem_cache.
199 *
200 * Once we can do anonymous structs (C11 standard) we could put a
201 * anonymous struct definition in these allocators so that the
202 * separate allocations in the kmem_cache structure of SLAB and
203 * SLUB is no longer needed.
204 */
205 struct kmem_cache {
206 unsigned int object_size;/* The original size of the object */
207 unsigned int size; /* The aligned/padded/added on size */
208 unsigned int align; /* Alignment as calculated */
209 slab_flags_t flags; /* Active flags on the slab */
210 unsigned int useroffset;/* Usercopy region offset */
211 unsigned int usersize; /* Usercopy region size */
212 const char *name; /* Slab name for sysfs */
213 int refcount; /* Use counter */
214 void (*ctor)(void *); /* Called on object slot creation */
215 struct list_head list; /* List of all slab caches on the system */
216 };
217
218 #endif /* CONFIG_SLOB */
219
220 #ifdef CONFIG_SLAB
221 #include <linux/slab_def.h>
222 #endif
223
224 #ifdef CONFIG_SLUB
225 #include <linux/slub_def.h>
226 #endif
227
228 #include <linux/memcontrol.h>
229 #include <linux/fault-inject.h>
230 #include <linux/kasan.h>
231 #include <linux/kmemleak.h>
232 #include <linux/random.h>
233 #include <linux/sched/mm.h>
234 #include <linux/list_lru.h>
235
236 /*
237 * State of the slab allocator.
238 *
239 * This is used to describe the states of the allocator during bootup.
240 * Allocators use this to gradually bootstrap themselves. Most allocators
241 * have the problem that the structures used for managing slab caches are
242 * allocated from slab caches themselves.
243 */
244 enum slab_state {
245 DOWN, /* No slab functionality yet */
246 PARTIAL, /* SLUB: kmem_cache_node available */
247 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
248 UP, /* Slab caches usable but not all extras yet */
249 FULL /* Everything is working */
250 };
251
252 extern enum slab_state slab_state;
253
254 /* The slab cache mutex protects the management structures during changes */
255 extern struct mutex slab_mutex;
256
257 /* The list of all slab caches on the system */
258 extern struct list_head slab_caches;
259
260 /* The slab cache that manages slab cache information */
261 extern struct kmem_cache *kmem_cache;
262
263 /* A table of kmalloc cache names and sizes */
264 extern const struct kmalloc_info_struct {
265 const char *name[NR_KMALLOC_TYPES];
266 unsigned int size;
267 } kmalloc_info[];
268
269 #ifndef CONFIG_SLOB
270 /* Kmalloc array related functions */
271 void setup_kmalloc_cache_index_table(void);
272 void create_kmalloc_caches(slab_flags_t);
273
274 /* Find the kmalloc slab corresponding for a certain size */
275 struct kmem_cache *kmalloc_slab(size_t, gfp_t);
276
277 void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags,
278 int node, size_t orig_size,
279 unsigned long caller);
280 void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller);
281 #endif
282
283 gfp_t kmalloc_fix_flags(gfp_t flags);
284
285 /* Functions provided by the slab allocators */
286 int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
287
288 struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size,
289 slab_flags_t flags, unsigned int useroffset,
290 unsigned int usersize);
291 extern void create_boot_cache(struct kmem_cache *, const char *name,
292 unsigned int size, slab_flags_t flags,
293 unsigned int useroffset, unsigned int usersize);
294
295 int slab_unmergeable(struct kmem_cache *s);
296 struct kmem_cache *find_mergeable(unsigned size, unsigned align,
297 slab_flags_t flags, const char *name, void (*ctor)(void *));
298 #ifndef CONFIG_SLOB
299 struct kmem_cache *
300 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
301 slab_flags_t flags, void (*ctor)(void *));
302
303 slab_flags_t kmem_cache_flags(unsigned int object_size,
304 slab_flags_t flags, const char *name);
305 #else
306 static inline struct kmem_cache *
307 __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
308 slab_flags_t flags, void (*ctor)(void *))
309 { return NULL; }
310
311 static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
312 slab_flags_t flags, const char *name)
313 {
314 return flags;
315 }
316 #endif
317
318
319 /* Legal flag mask for kmem_cache_create(), for various configurations */
320 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
321 SLAB_CACHE_DMA32 | SLAB_PANIC | \
322 SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
323
324 #if defined(CONFIG_DEBUG_SLAB)
325 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
326 #elif defined(CONFIG_SLUB_DEBUG)
327 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
328 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
329 #else
330 #define SLAB_DEBUG_FLAGS (0)
331 #endif
332
333 #if defined(CONFIG_SLAB)
334 #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
335 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
336 SLAB_ACCOUNT)
337 #elif defined(CONFIG_SLUB)
338 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
339 SLAB_TEMPORARY | SLAB_ACCOUNT | SLAB_NO_USER_FLAGS)
340 #else
341 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE)
342 #endif
343
344 /* Common flags available with current configuration */
345 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
346
347 /* Common flags permitted for kmem_cache_create */
348 #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
349 SLAB_RED_ZONE | \
350 SLAB_POISON | \
351 SLAB_STORE_USER | \
352 SLAB_TRACE | \
353 SLAB_CONSISTENCY_CHECKS | \
354 SLAB_MEM_SPREAD | \
355 SLAB_NOLEAKTRACE | \
356 SLAB_RECLAIM_ACCOUNT | \
357 SLAB_TEMPORARY | \
358 SLAB_ACCOUNT | \
359 SLAB_NO_USER_FLAGS)
360
361 bool __kmem_cache_empty(struct kmem_cache *);
362 int __kmem_cache_shutdown(struct kmem_cache *);
363 void __kmem_cache_release(struct kmem_cache *);
364 int __kmem_cache_shrink(struct kmem_cache *);
365 void slab_kmem_cache_release(struct kmem_cache *);
366
367 struct seq_file;
368 struct file;
369
370 struct slabinfo {
371 unsigned long active_objs;
372 unsigned long num_objs;
373 unsigned long active_slabs;
374 unsigned long num_slabs;
375 unsigned long shared_avail;
376 unsigned int limit;
377 unsigned int batchcount;
378 unsigned int shared;
379 unsigned int objects_per_slab;
380 unsigned int cache_order;
381 };
382
383 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
384 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
385 ssize_t slabinfo_write(struct file *file, const char __user *buffer,
386 size_t count, loff_t *ppos);
387
388 static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s)
389 {
390 return (s->flags & SLAB_RECLAIM_ACCOUNT) ?
391 NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B;
392 }
393
394 #ifdef CONFIG_SLUB_DEBUG
395 #ifdef CONFIG_SLUB_DEBUG_ON
396 DECLARE_STATIC_KEY_TRUE(slub_debug_enabled);
397 #else
398 DECLARE_STATIC_KEY_FALSE(slub_debug_enabled);
399 #endif
400 extern void print_tracking(struct kmem_cache *s, void *object);
401 long validate_slab_cache(struct kmem_cache *s);
402 static inline bool __slub_debug_enabled(void)
403 {
404 return static_branch_unlikely(&slub_debug_enabled);
405 }
406 #else
407 static inline void print_tracking(struct kmem_cache *s, void *object)
408 {
409 }
410 static inline bool __slub_debug_enabled(void)
411 {
412 return false;
413 }
414 #endif
415
416 /*
417 * Returns true if any of the specified slub_debug flags is enabled for the
418 * cache. Use only for flags parsed by setup_slub_debug() as it also enables
419 * the static key.
420 */
421 static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags)
422 {
423 if (IS_ENABLED(CONFIG_SLUB_DEBUG))
424 VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
425 if (__slub_debug_enabled())
426 return s->flags & flags;
427 return false;
428 }
429
430 #ifdef CONFIG_MEMCG_KMEM
431 /*
432 * slab_objcgs - get the object cgroups vector associated with a slab
433 * @slab: a pointer to the slab struct
434 *
435 * Returns a pointer to the object cgroups vector associated with the slab,
436 * or NULL if no such vector has been associated yet.
437 */
438 static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
439 {
440 unsigned long memcg_data = READ_ONCE(slab->memcg_data);
441
442 VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS),
443 slab_page(slab));
444 VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab));
445
446 return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
447 }
448
449 int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
450 gfp_t gfp, bool new_slab);
451 void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
452 enum node_stat_item idx, int nr);
453
454 static inline void memcg_free_slab_cgroups(struct slab *slab)
455 {
456 kfree(slab_objcgs(slab));
457 slab->memcg_data = 0;
458 }
459
460 static inline size_t obj_full_size(struct kmem_cache *s)
461 {
462 /*
463 * For each accounted object there is an extra space which is used
464 * to store obj_cgroup membership. Charge it too.
465 */
466 return s->size + sizeof(struct obj_cgroup *);
467 }
468
469 /*
470 * Returns false if the allocation should fail.
471 */
472 static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
473 struct list_lru *lru,
474 struct obj_cgroup **objcgp,
475 size_t objects, gfp_t flags)
476 {
477 struct obj_cgroup *objcg;
478
479 if (!memcg_kmem_enabled())
480 return true;
481
482 if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT))
483 return true;
484
485 objcg = get_obj_cgroup_from_current();
486 if (!objcg)
487 return true;
488
489 if (lru) {
490 int ret;
491 struct mem_cgroup *memcg;
492
493 memcg = get_mem_cgroup_from_objcg(objcg);
494 ret = memcg_list_lru_alloc(memcg, lru, flags);
495 css_put(&memcg->css);
496
497 if (ret)
498 goto out;
499 }
500
501 if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s)))
502 goto out;
503
504 *objcgp = objcg;
505 return true;
506 out:
507 obj_cgroup_put(objcg);
508 return false;
509 }
510
511 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
512 struct obj_cgroup *objcg,
513 gfp_t flags, size_t size,
514 void **p)
515 {
516 struct slab *slab;
517 unsigned long off;
518 size_t i;
519
520 if (!memcg_kmem_enabled() || !objcg)
521 return;
522
523 for (i = 0; i < size; i++) {
524 if (likely(p[i])) {
525 slab = virt_to_slab(p[i]);
526
527 if (!slab_objcgs(slab) &&
528 memcg_alloc_slab_cgroups(slab, s, flags,
529 false)) {
530 obj_cgroup_uncharge(objcg, obj_full_size(s));
531 continue;
532 }
533
534 off = obj_to_index(s, slab, p[i]);
535 obj_cgroup_get(objcg);
536 slab_objcgs(slab)[off] = objcg;
537 mod_objcg_state(objcg, slab_pgdat(slab),
538 cache_vmstat_idx(s), obj_full_size(s));
539 } else {
540 obj_cgroup_uncharge(objcg, obj_full_size(s));
541 }
542 }
543 obj_cgroup_put(objcg);
544 }
545
546 static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab,
547 void **p, int objects)
548 {
549 struct obj_cgroup **objcgs;
550 int i;
551
552 if (!memcg_kmem_enabled())
553 return;
554
555 objcgs = slab_objcgs(slab);
556 if (!objcgs)
557 return;
558
559 for (i = 0; i < objects; i++) {
560 struct obj_cgroup *objcg;
561 unsigned int off;
562
563 off = obj_to_index(s, slab, p[i]);
564 objcg = objcgs[off];
565 if (!objcg)
566 continue;
567
568 objcgs[off] = NULL;
569 obj_cgroup_uncharge(objcg, obj_full_size(s));
570 mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s),
571 -obj_full_size(s));
572 obj_cgroup_put(objcg);
573 }
574 }
575
576 #else /* CONFIG_MEMCG_KMEM */
577 static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
578 {
579 return NULL;
580 }
581
582 static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
583 {
584 return NULL;
585 }
586
587 static inline int memcg_alloc_slab_cgroups(struct slab *slab,
588 struct kmem_cache *s, gfp_t gfp,
589 bool new_slab)
590 {
591 return 0;
592 }
593
594 static inline void memcg_free_slab_cgroups(struct slab *slab)
595 {
596 }
597
598 static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
599 struct list_lru *lru,
600 struct obj_cgroup **objcgp,
601 size_t objects, gfp_t flags)
602 {
603 return true;
604 }
605
606 static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
607 struct obj_cgroup *objcg,
608 gfp_t flags, size_t size,
609 void **p)
610 {
611 }
612
613 static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab,
614 void **p, int objects)
615 {
616 }
617 #endif /* CONFIG_MEMCG_KMEM */
618
619 #ifndef CONFIG_SLOB
620 static inline struct kmem_cache *virt_to_cache(const void *obj)
621 {
622 struct slab *slab;
623
624 slab = virt_to_slab(obj);
625 if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n",
626 __func__))
627 return NULL;
628 return slab->slab_cache;
629 }
630
631 static __always_inline void account_slab(struct slab *slab, int order,
632 struct kmem_cache *s, gfp_t gfp)
633 {
634 if (memcg_kmem_enabled() && (s->flags & SLAB_ACCOUNT))
635 memcg_alloc_slab_cgroups(slab, s, gfp, true);
636
637 mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s),
638 PAGE_SIZE << order);
639 }
640
641 static __always_inline void unaccount_slab(struct slab *slab, int order,
642 struct kmem_cache *s)
643 {
644 if (memcg_kmem_enabled())
645 memcg_free_slab_cgroups(slab);
646
647 mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s),
648 -(PAGE_SIZE << order));
649 }
650
651 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
652 {
653 struct kmem_cache *cachep;
654
655 if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) &&
656 !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS))
657 return s;
658
659 cachep = virt_to_cache(x);
660 if (WARN(cachep && cachep != s,
661 "%s: Wrong slab cache. %s but object is from %s\n",
662 __func__, s->name, cachep->name))
663 print_tracking(cachep, x);
664 return cachep;
665 }
666
667 void free_large_kmalloc(struct folio *folio, void *object);
668
669 #endif /* CONFIG_SLOB */
670
671 size_t __ksize(const void *objp);
672
673 static inline size_t slab_ksize(const struct kmem_cache *s)
674 {
675 #ifndef CONFIG_SLUB
676 return s->object_size;
677
678 #else /* CONFIG_SLUB */
679 # ifdef CONFIG_SLUB_DEBUG
680 /*
681 * Debugging requires use of the padding between object
682 * and whatever may come after it.
683 */
684 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
685 return s->object_size;
686 # endif
687 if (s->flags & SLAB_KASAN)
688 return s->object_size;
689 /*
690 * If we have the need to store the freelist pointer
691 * back there or track user information then we can
692 * only use the space before that information.
693 */
694 if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
695 return s->inuse;
696 /*
697 * Else we can use all the padding etc for the allocation
698 */
699 return s->size;
700 #endif
701 }
702
703 static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
704 struct list_lru *lru,
705 struct obj_cgroup **objcgp,
706 size_t size, gfp_t flags)
707 {
708 flags &= gfp_allowed_mask;
709
710 might_alloc(flags);
711
712 if (should_failslab(s, flags))
713 return NULL;
714
715 if (!memcg_slab_pre_alloc_hook(s, lru, objcgp, size, flags))
716 return NULL;
717
718 return s;
719 }
720
721 static inline void slab_post_alloc_hook(struct kmem_cache *s,
722 struct obj_cgroup *objcg, gfp_t flags,
723 size_t size, void **p, bool init)
724 {
725 size_t i;
726
727 flags &= gfp_allowed_mask;
728
729 /*
730 * As memory initialization might be integrated into KASAN,
731 * kasan_slab_alloc and initialization memset must be
732 * kept together to avoid discrepancies in behavior.
733 *
734 * As p[i] might get tagged, memset and kmemleak hook come after KASAN.
735 */
736 for (i = 0; i < size; i++) {
737 p[i] = kasan_slab_alloc(s, p[i], flags, init);
738 if (p[i] && init && !kasan_has_integrated_init())
739 memset(p[i], 0, s->object_size);
740 kmemleak_alloc_recursive(p[i], s->object_size, 1,
741 s->flags, flags);
742 kmsan_slab_alloc(s, p[i], flags);
743 }
744
745 memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
746 }
747
748 #ifndef CONFIG_SLOB
749 /*
750 * The slab lists for all objects.
751 */
752 struct kmem_cache_node {
753 spinlock_t list_lock;
754
755 #ifdef CONFIG_SLAB
756 struct list_head slabs_partial; /* partial list first, better asm code */
757 struct list_head slabs_full;
758 struct list_head slabs_free;
759 unsigned long total_slabs; /* length of all slab lists */
760 unsigned long free_slabs; /* length of free slab list only */
761 unsigned long free_objects;
762 unsigned int free_limit;
763 unsigned int colour_next; /* Per-node cache coloring */
764 struct array_cache *shared; /* shared per node */
765 struct alien_cache **alien; /* on other nodes */
766 unsigned long next_reap; /* updated without locking */
767 int free_touched; /* updated without locking */
768 #endif
769
770 #ifdef CONFIG_SLUB
771 unsigned long nr_partial;
772 struct list_head partial;
773 #ifdef CONFIG_SLUB_DEBUG
774 atomic_long_t nr_slabs;
775 atomic_long_t total_objects;
776 struct list_head full;
777 #endif
778 #endif
779
780 };
781
782 static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
783 {
784 return s->node[node];
785 }
786
787 /*
788 * Iterator over all nodes. The body will be executed for each node that has
789 * a kmem_cache_node structure allocated (which is true for all online nodes)
790 */
791 #define for_each_kmem_cache_node(__s, __node, __n) \
792 for (__node = 0; __node < nr_node_ids; __node++) \
793 if ((__n = get_node(__s, __node)))
794
795 #endif
796
797 #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
798 void dump_unreclaimable_slab(void);
799 #else
800 static inline void dump_unreclaimable_slab(void)
801 {
802 }
803 #endif
804
805 void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
806
807 #ifdef CONFIG_SLAB_FREELIST_RANDOM
808 int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
809 gfp_t gfp);
810 void cache_random_seq_destroy(struct kmem_cache *cachep);
811 #else
812 static inline int cache_random_seq_create(struct kmem_cache *cachep,
813 unsigned int count, gfp_t gfp)
814 {
815 return 0;
816 }
817 static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
818 #endif /* CONFIG_SLAB_FREELIST_RANDOM */
819
820 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c)
821 {
822 if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
823 &init_on_alloc)) {
824 if (c->ctor)
825 return false;
826 if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))
827 return flags & __GFP_ZERO;
828 return true;
829 }
830 return flags & __GFP_ZERO;
831 }
832
833 static inline bool slab_want_init_on_free(struct kmem_cache *c)
834 {
835 if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
836 &init_on_free))
837 return !(c->ctor ||
838 (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)));
839 return false;
840 }
841
842 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG)
843 void debugfs_slab_release(struct kmem_cache *);
844 #else
845 static inline void debugfs_slab_release(struct kmem_cache *s) { }
846 #endif
847
848 #ifdef CONFIG_PRINTK
849 #define KS_ADDRS_COUNT 16
850 struct kmem_obj_info {
851 void *kp_ptr;
852 struct slab *kp_slab;
853 void *kp_objp;
854 unsigned long kp_data_offset;
855 struct kmem_cache *kp_slab_cache;
856 void *kp_ret;
857 void *kp_stack[KS_ADDRS_COUNT];
858 void *kp_free_stack[KS_ADDRS_COUNT];
859 };
860 void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab);
861 #endif
862
863 #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
864 void __check_heap_object(const void *ptr, unsigned long n,
865 const struct slab *slab, bool to_user);
866 #else
867 static inline
868 void __check_heap_object(const void *ptr, unsigned long n,
869 const struct slab *slab, bool to_user)
870 {
871 }
872 #endif
873
874 #endif /* MM_SLAB_H */