Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0 */
2 : #ifndef MM_SLAB_H
3 : #define MM_SLAB_H
4 : /*
5 : * Internal slab definitions
6 : */
7 : void __init kmem_cache_init(void);
8 :
9 : /* Reuses the bits in struct page */
10 : struct slab {
11 : unsigned long __page_flags;
12 :
13 : #if defined(CONFIG_SLAB)
14 :
15 : struct kmem_cache *slab_cache;
16 : union {
17 : struct {
18 : struct list_head slab_list;
19 : void *freelist; /* array of free object indexes */
20 : void *s_mem; /* first object */
21 : };
22 : struct rcu_head rcu_head;
23 : };
24 : unsigned int active;
25 :
26 : #elif defined(CONFIG_SLUB)
27 :
28 : struct kmem_cache *slab_cache;
29 : union {
30 : struct {
31 : union {
32 : struct list_head slab_list;
33 : #ifdef CONFIG_SLUB_CPU_PARTIAL
34 : struct {
35 : struct slab *next;
36 : int slabs; /* Nr of slabs left */
37 : };
38 : #endif
39 : };
40 : /* Double-word boundary */
41 : void *freelist; /* first free object */
42 : union {
43 : unsigned long counters;
44 : struct {
45 : unsigned inuse:16;
46 : unsigned objects:15;
47 : unsigned frozen:1;
48 : };
49 : };
50 : };
51 : struct rcu_head rcu_head;
52 : };
53 : unsigned int __unused;
54 :
55 : #else
56 : #error "Unexpected slab allocator configured"
57 : #endif
58 :
59 : atomic_t __page_refcount;
60 : #ifdef CONFIG_MEMCG
61 : unsigned long memcg_data;
62 : #endif
63 : };
64 :
65 : #define SLAB_MATCH(pg, sl) \
66 : static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl))
67 : SLAB_MATCH(flags, __page_flags);
68 : SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */
69 : SLAB_MATCH(_refcount, __page_refcount);
70 : #ifdef CONFIG_MEMCG
71 : SLAB_MATCH(memcg_data, memcg_data);
72 : #endif
73 : #undef SLAB_MATCH
74 : static_assert(sizeof(struct slab) <= sizeof(struct page));
75 : #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB)
76 : static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *)));
77 : #endif
78 :
79 : /**
80 : * folio_slab - Converts from folio to slab.
81 : * @folio: The folio.
82 : *
83 : * Currently struct slab is a different representation of a folio where
84 : * folio_test_slab() is true.
85 : *
86 : * Return: The slab which contains this folio.
87 : */
88 : #define folio_slab(folio) (_Generic((folio), \
89 : const struct folio *: (const struct slab *)(folio), \
90 : struct folio *: (struct slab *)(folio)))
91 :
92 : /**
93 : * slab_folio - The folio allocated for a slab
94 : * @slab: The slab.
95 : *
96 : * Slabs are allocated as folios that contain the individual objects and are
97 : * using some fields in the first struct page of the folio - those fields are
98 : * now accessed by struct slab. It is occasionally necessary to convert back to
99 : * a folio in order to communicate with the rest of the mm. Please use this
100 : * helper function instead of casting yourself, as the implementation may change
101 : * in the future.
102 : */
103 : #define slab_folio(s) (_Generic((s), \
104 : const struct slab *: (const struct folio *)s, \
105 : struct slab *: (struct folio *)s))
106 :
107 : /**
108 : * page_slab - Converts from first struct page to slab.
109 : * @p: The first (either head of compound or single) page of slab.
110 : *
111 : * A temporary wrapper to convert struct page to struct slab in situations where
112 : * we know the page is the compound head, or single order-0 page.
113 : *
114 : * Long-term ideally everything would work with struct slab directly or go
115 : * through folio to struct slab.
116 : *
117 : * Return: The slab which contains this page
118 : */
119 : #define page_slab(p) (_Generic((p), \
120 : const struct page *: (const struct slab *)(p), \
121 : struct page *: (struct slab *)(p)))
122 :
123 : /**
124 : * slab_page - The first struct page allocated for a slab
125 : * @slab: The slab.
126 : *
127 : * A convenience wrapper for converting slab to the first struct page of the
128 : * underlying folio, to communicate with code not yet converted to folio or
129 : * struct slab.
130 : */
131 : #define slab_page(s) folio_page(slab_folio(s), 0)
132 :
133 : /*
134 : * If network-based swap is enabled, sl*b must keep track of whether pages
135 : * were allocated from pfmemalloc reserves.
136 : */
137 : static inline bool slab_test_pfmemalloc(const struct slab *slab)
138 : {
139 4602 : return folio_test_active((struct folio *)slab_folio(slab));
140 : }
141 :
142 : static inline void slab_set_pfmemalloc(struct slab *slab)
143 : {
144 0 : folio_set_active(slab_folio(slab));
145 : }
146 :
147 : static inline void slab_clear_pfmemalloc(struct slab *slab)
148 : {
149 : folio_clear_active(slab_folio(slab));
150 : }
151 :
152 : static inline void __slab_clear_pfmemalloc(struct slab *slab)
153 : {
154 1753 : __folio_clear_active(slab_folio(slab));
155 : }
156 :
157 : static inline void *slab_address(const struct slab *slab)
158 : {
159 2194 : return folio_address(slab_folio(slab));
160 : }
161 :
162 : static inline int slab_nid(const struct slab *slab)
163 : {
164 7584 : return folio_nid(slab_folio(slab));
165 : }
166 :
167 : static inline pg_data_t *slab_pgdat(const struct slab *slab)
168 : {
169 3947 : return folio_pgdat(slab_folio(slab));
170 : }
171 :
172 : static inline struct slab *virt_to_slab(const void *addr)
173 : {
174 49059 : struct folio *folio = virt_to_folio(addr);
175 :
176 49059 : if (!folio_test_slab(folio))
177 : return NULL;
178 :
179 : return folio_slab(folio);
180 : }
181 :
182 : static inline int slab_order(const struct slab *slab)
183 : {
184 0 : return folio_order((struct folio *)slab_folio(slab));
185 : }
186 :
187 : static inline size_t slab_size(const struct slab *slab)
188 : {
189 0 : return PAGE_SIZE << slab_order(slab);
190 : }
191 :
192 : #ifdef CONFIG_SLAB
193 : #include <linux/slab_def.h>
194 : #endif
195 :
196 : #ifdef CONFIG_SLUB
197 : #include <linux/slub_def.h>
198 : #endif
199 :
200 : #include <linux/memcontrol.h>
201 : #include <linux/fault-inject.h>
202 : #include <linux/kasan.h>
203 : #include <linux/kmemleak.h>
204 : #include <linux/random.h>
205 : #include <linux/sched/mm.h>
206 : #include <linux/list_lru.h>
207 :
208 : /*
209 : * State of the slab allocator.
210 : *
211 : * This is used to describe the states of the allocator during bootup.
212 : * Allocators use this to gradually bootstrap themselves. Most allocators
213 : * have the problem that the structures used for managing slab caches are
214 : * allocated from slab caches themselves.
215 : */
216 : enum slab_state {
217 : DOWN, /* No slab functionality yet */
218 : PARTIAL, /* SLUB: kmem_cache_node available */
219 : PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
220 : UP, /* Slab caches usable but not all extras yet */
221 : FULL /* Everything is working */
222 : };
223 :
224 : extern enum slab_state slab_state;
225 :
226 : /* The slab cache mutex protects the management structures during changes */
227 : extern struct mutex slab_mutex;
228 :
229 : /* The list of all slab caches on the system */
230 : extern struct list_head slab_caches;
231 :
232 : /* The slab cache that manages slab cache information */
233 : extern struct kmem_cache *kmem_cache;
234 :
235 : /* A table of kmalloc cache names and sizes */
236 : extern const struct kmalloc_info_struct {
237 : const char *name[NR_KMALLOC_TYPES];
238 : unsigned int size;
239 : } kmalloc_info[];
240 :
241 : /* Kmalloc array related functions */
242 : void setup_kmalloc_cache_index_table(void);
243 : void create_kmalloc_caches(slab_flags_t);
244 :
245 : /* Find the kmalloc slab corresponding for a certain size */
246 : struct kmem_cache *kmalloc_slab(size_t, gfp_t);
247 :
248 : void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags,
249 : int node, size_t orig_size,
250 : unsigned long caller);
251 : void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller);
252 :
253 : gfp_t kmalloc_fix_flags(gfp_t flags);
254 :
255 : /* Functions provided by the slab allocators */
256 : int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
257 :
258 : struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size,
259 : slab_flags_t flags, unsigned int useroffset,
260 : unsigned int usersize);
261 : extern void create_boot_cache(struct kmem_cache *, const char *name,
262 : unsigned int size, slab_flags_t flags,
263 : unsigned int useroffset, unsigned int usersize);
264 :
265 : int slab_unmergeable(struct kmem_cache *s);
266 : struct kmem_cache *find_mergeable(unsigned size, unsigned align,
267 : slab_flags_t flags, const char *name, void (*ctor)(void *));
268 : struct kmem_cache *
269 : __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
270 : slab_flags_t flags, void (*ctor)(void *));
271 :
272 : slab_flags_t kmem_cache_flags(unsigned int object_size,
273 : slab_flags_t flags, const char *name);
274 :
275 : static inline bool is_kmalloc_cache(struct kmem_cache *s)
276 : {
277 : return (s->flags & SLAB_KMALLOC);
278 : }
279 :
280 : /* Legal flag mask for kmem_cache_create(), for various configurations */
281 : #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
282 : SLAB_CACHE_DMA32 | SLAB_PANIC | \
283 : SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
284 :
285 : #if defined(CONFIG_DEBUG_SLAB)
286 : #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
287 : #elif defined(CONFIG_SLUB_DEBUG)
288 : #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
289 : SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
290 : #else
291 : #define SLAB_DEBUG_FLAGS (0)
292 : #endif
293 :
294 : #if defined(CONFIG_SLAB)
295 : #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
296 : SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
297 : SLAB_ACCOUNT)
298 : #elif defined(CONFIG_SLUB)
299 : #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
300 : SLAB_TEMPORARY | SLAB_ACCOUNT | \
301 : SLAB_NO_USER_FLAGS | SLAB_KMALLOC)
302 : #else
303 : #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE)
304 : #endif
305 :
306 : /* Common flags available with current configuration */
307 : #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
308 :
309 : /* Common flags permitted for kmem_cache_create */
310 : #define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
311 : SLAB_RED_ZONE | \
312 : SLAB_POISON | \
313 : SLAB_STORE_USER | \
314 : SLAB_TRACE | \
315 : SLAB_CONSISTENCY_CHECKS | \
316 : SLAB_MEM_SPREAD | \
317 : SLAB_NOLEAKTRACE | \
318 : SLAB_RECLAIM_ACCOUNT | \
319 : SLAB_TEMPORARY | \
320 : SLAB_ACCOUNT | \
321 : SLAB_KMALLOC | \
322 : SLAB_NO_USER_FLAGS)
323 :
324 : bool __kmem_cache_empty(struct kmem_cache *);
325 : int __kmem_cache_shutdown(struct kmem_cache *);
326 : void __kmem_cache_release(struct kmem_cache *);
327 : int __kmem_cache_shrink(struct kmem_cache *);
328 : void slab_kmem_cache_release(struct kmem_cache *);
329 :
330 : struct seq_file;
331 : struct file;
332 :
333 : struct slabinfo {
334 : unsigned long active_objs;
335 : unsigned long num_objs;
336 : unsigned long active_slabs;
337 : unsigned long num_slabs;
338 : unsigned long shared_avail;
339 : unsigned int limit;
340 : unsigned int batchcount;
341 : unsigned int shared;
342 : unsigned int objects_per_slab;
343 : unsigned int cache_order;
344 : };
345 :
346 : void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
347 : void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
348 : ssize_t slabinfo_write(struct file *file, const char __user *buffer,
349 : size_t count, loff_t *ppos);
350 :
351 : static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s)
352 : {
353 3947 : return (s->flags & SLAB_RECLAIM_ACCOUNT) ?
354 3947 : NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B;
355 : }
356 :
357 : #ifdef CONFIG_SLUB_DEBUG
358 : #ifdef CONFIG_SLUB_DEBUG_ON
359 : DECLARE_STATIC_KEY_TRUE(slub_debug_enabled);
360 : #else
361 : DECLARE_STATIC_KEY_FALSE(slub_debug_enabled);
362 : #endif
363 : extern void print_tracking(struct kmem_cache *s, void *object);
364 : long validate_slab_cache(struct kmem_cache *s);
365 : static inline bool __slub_debug_enabled(void)
366 : {
367 169265 : return static_branch_unlikely(&slub_debug_enabled);
368 : }
369 : #else
370 : static inline void print_tracking(struct kmem_cache *s, void *object)
371 : {
372 : }
373 : static inline bool __slub_debug_enabled(void)
374 : {
375 : return false;
376 : }
377 : #endif
378 :
379 : /*
380 : * Returns true if any of the specified slub_debug flags is enabled for the
381 : * cache. Use only for flags parsed by setup_slub_debug() as it also enables
382 : * the static key.
383 : */
384 : static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t flags)
385 : {
386 : if (IS_ENABLED(CONFIG_SLUB_DEBUG))
387 : VM_WARN_ON_ONCE(!(flags & SLAB_DEBUG_FLAGS));
388 169264 : if (__slub_debug_enabled())
389 0 : return s->flags & flags;
390 : return false;
391 : }
392 :
393 : #ifdef CONFIG_MEMCG_KMEM
394 : /*
395 : * slab_objcgs - get the object cgroups vector associated with a slab
396 : * @slab: a pointer to the slab struct
397 : *
398 : * Returns a pointer to the object cgroups vector associated with the slab,
399 : * or NULL if no such vector has been associated yet.
400 : */
401 : static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
402 : {
403 : unsigned long memcg_data = READ_ONCE(slab->memcg_data);
404 :
405 : VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS),
406 : slab_page(slab));
407 : VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, slab_page(slab));
408 :
409 : return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
410 : }
411 :
412 : int memcg_alloc_slab_cgroups(struct slab *slab, struct kmem_cache *s,
413 : gfp_t gfp, bool new_slab);
414 : void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
415 : enum node_stat_item idx, int nr);
416 :
417 : static inline void memcg_free_slab_cgroups(struct slab *slab)
418 : {
419 : kfree(slab_objcgs(slab));
420 : slab->memcg_data = 0;
421 : }
422 :
423 : static inline size_t obj_full_size(struct kmem_cache *s)
424 : {
425 : /*
426 : * For each accounted object there is an extra space which is used
427 : * to store obj_cgroup membership. Charge it too.
428 : */
429 : return s->size + sizeof(struct obj_cgroup *);
430 : }
431 :
432 : /*
433 : * Returns false if the allocation should fail.
434 : */
435 : static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
436 : struct list_lru *lru,
437 : struct obj_cgroup **objcgp,
438 : size_t objects, gfp_t flags)
439 : {
440 : struct obj_cgroup *objcg;
441 :
442 : if (!memcg_kmem_online())
443 : return true;
444 :
445 : if (!(flags & __GFP_ACCOUNT) && !(s->flags & SLAB_ACCOUNT))
446 : return true;
447 :
448 : objcg = get_obj_cgroup_from_current();
449 : if (!objcg)
450 : return true;
451 :
452 : if (lru) {
453 : int ret;
454 : struct mem_cgroup *memcg;
455 :
456 : memcg = get_mem_cgroup_from_objcg(objcg);
457 : ret = memcg_list_lru_alloc(memcg, lru, flags);
458 : css_put(&memcg->css);
459 :
460 : if (ret)
461 : goto out;
462 : }
463 :
464 : if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s)))
465 : goto out;
466 :
467 : *objcgp = objcg;
468 : return true;
469 : out:
470 : obj_cgroup_put(objcg);
471 : return false;
472 : }
473 :
474 : static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
475 : struct obj_cgroup *objcg,
476 : gfp_t flags, size_t size,
477 : void **p)
478 : {
479 : struct slab *slab;
480 : unsigned long off;
481 : size_t i;
482 :
483 : if (!memcg_kmem_online() || !objcg)
484 : return;
485 :
486 : for (i = 0; i < size; i++) {
487 : if (likely(p[i])) {
488 : slab = virt_to_slab(p[i]);
489 :
490 : if (!slab_objcgs(slab) &&
491 : memcg_alloc_slab_cgroups(slab, s, flags,
492 : false)) {
493 : obj_cgroup_uncharge(objcg, obj_full_size(s));
494 : continue;
495 : }
496 :
497 : off = obj_to_index(s, slab, p[i]);
498 : obj_cgroup_get(objcg);
499 : slab_objcgs(slab)[off] = objcg;
500 : mod_objcg_state(objcg, slab_pgdat(slab),
501 : cache_vmstat_idx(s), obj_full_size(s));
502 : } else {
503 : obj_cgroup_uncharge(objcg, obj_full_size(s));
504 : }
505 : }
506 : obj_cgroup_put(objcg);
507 : }
508 :
509 : static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab,
510 : void **p, int objects)
511 : {
512 : struct obj_cgroup **objcgs;
513 : int i;
514 :
515 : if (!memcg_kmem_online())
516 : return;
517 :
518 : objcgs = slab_objcgs(slab);
519 : if (!objcgs)
520 : return;
521 :
522 : for (i = 0; i < objects; i++) {
523 : struct obj_cgroup *objcg;
524 : unsigned int off;
525 :
526 : off = obj_to_index(s, slab, p[i]);
527 : objcg = objcgs[off];
528 : if (!objcg)
529 : continue;
530 :
531 : objcgs[off] = NULL;
532 : obj_cgroup_uncharge(objcg, obj_full_size(s));
533 : mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s),
534 : -obj_full_size(s));
535 : obj_cgroup_put(objcg);
536 : }
537 : }
538 :
539 : #else /* CONFIG_MEMCG_KMEM */
540 : static inline struct obj_cgroup **slab_objcgs(struct slab *slab)
541 : {
542 : return NULL;
543 : }
544 :
545 : static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
546 : {
547 : return NULL;
548 : }
549 :
550 : static inline int memcg_alloc_slab_cgroups(struct slab *slab,
551 : struct kmem_cache *s, gfp_t gfp,
552 : bool new_slab)
553 : {
554 : return 0;
555 : }
556 :
557 : static inline void memcg_free_slab_cgroups(struct slab *slab)
558 : {
559 : }
560 :
561 : static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s,
562 : struct list_lru *lru,
563 : struct obj_cgroup **objcgp,
564 : size_t objects, gfp_t flags)
565 : {
566 : return true;
567 : }
568 :
569 : static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
570 : struct obj_cgroup *objcg,
571 : gfp_t flags, size_t size,
572 : void **p)
573 : {
574 : }
575 :
576 : static inline void memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab,
577 : void **p, int objects)
578 : {
579 : }
580 : #endif /* CONFIG_MEMCG_KMEM */
581 :
582 0 : static inline struct kmem_cache *virt_to_cache(const void *obj)
583 : {
584 : struct slab *slab;
585 :
586 0 : slab = virt_to_slab(obj);
587 0 : if (WARN_ONCE(!slab, "%s: Object is not a Slab page!\n",
588 : __func__))
589 : return NULL;
590 0 : return slab->slab_cache;
591 : }
592 :
593 : static __always_inline void account_slab(struct slab *slab, int order,
594 : struct kmem_cache *s, gfp_t gfp)
595 : {
596 : if (memcg_kmem_online() && (s->flags & SLAB_ACCOUNT))
597 : memcg_alloc_slab_cgroups(slab, s, gfp, true);
598 :
599 8776 : mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s),
600 2194 : PAGE_SIZE << order);
601 : }
602 :
603 : static __always_inline void unaccount_slab(struct slab *slab, int order,
604 : struct kmem_cache *s)
605 : {
606 : if (memcg_kmem_online())
607 : memcg_free_slab_cgroups(slab);
608 :
609 7012 : mod_node_page_state(slab_pgdat(slab), cache_vmstat_idx(s),
610 1753 : -(PAGE_SIZE << order));
611 : }
612 :
613 5553 : static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
614 : {
615 : struct kmem_cache *cachep;
616 :
617 5553 : if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) &&
618 11106 : !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS))
619 : return s;
620 :
621 0 : cachep = virt_to_cache(x);
622 0 : if (WARN(cachep && cachep != s,
623 : "%s: Wrong slab cache. %s but object is from %s\n",
624 : __func__, s->name, cachep->name))
625 0 : print_tracking(cachep, x);
626 : return cachep;
627 : }
628 :
629 : void free_large_kmalloc(struct folio *folio, void *object);
630 :
631 : size_t __ksize(const void *objp);
632 :
633 : static inline size_t slab_ksize(const struct kmem_cache *s)
634 : {
635 : #ifndef CONFIG_SLUB
636 : return s->object_size;
637 :
638 : #else /* CONFIG_SLUB */
639 : # ifdef CONFIG_SLUB_DEBUG
640 : /*
641 : * Debugging requires use of the padding between object
642 : * and whatever may come after it.
643 : */
644 118 : if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
645 0 : return s->object_size;
646 : # endif
647 : if (s->flags & SLAB_KASAN)
648 : return s->object_size;
649 : /*
650 : * If we have the need to store the freelist pointer
651 : * back there or track user information then we can
652 : * only use the space before that information.
653 : */
654 118 : if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
655 0 : return s->inuse;
656 : /*
657 : * Else we can use all the padding etc for the allocation
658 : */
659 118 : return s->size;
660 : #endif
661 : }
662 :
663 : static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
664 : struct list_lru *lru,
665 : struct obj_cgroup **objcgp,
666 : size_t size, gfp_t flags)
667 : {
668 61648 : flags &= gfp_allowed_mask;
669 :
670 61648 : might_alloc(flags);
671 :
672 61648 : if (should_failslab(s, flags))
673 : return NULL;
674 :
675 61648 : if (!memcg_slab_pre_alloc_hook(s, lru, objcgp, size, flags))
676 : return NULL;
677 :
678 : return s;
679 : }
680 :
681 61648 : static inline void slab_post_alloc_hook(struct kmem_cache *s,
682 : struct obj_cgroup *objcg, gfp_t flags,
683 : size_t size, void **p, bool init,
684 : unsigned int orig_size)
685 : {
686 61648 : unsigned int zero_size = s->object_size;
687 : size_t i;
688 :
689 61648 : flags &= gfp_allowed_mask;
690 :
691 : /*
692 : * For kmalloc object, the allocated memory size(object_size) is likely
693 : * larger than the requested size(orig_size). If redzone check is
694 : * enabled for the extra space, don't zero it, as it will be redzoned
695 : * soon. The redzone operation for this extra space could be seen as a
696 : * replacement of current poisoning under certain debug option, and
697 : * won't break other sanity checks.
698 : */
699 123296 : if (kmem_cache_debug_flags(s, SLAB_STORE_USER | SLAB_RED_ZONE) &&
700 0 : (s->flags & SLAB_KMALLOC))
701 0 : zero_size = orig_size;
702 :
703 : /*
704 : * As memory initialization might be integrated into KASAN,
705 : * kasan_slab_alloc and initialization memset must be
706 : * kept together to avoid discrepancies in behavior.
707 : *
708 : * As p[i] might get tagged, memset and kmemleak hook come after KASAN.
709 : */
710 123296 : for (i = 0; i < size; i++) {
711 61648 : p[i] = kasan_slab_alloc(s, p[i], flags, init);
712 61648 : if (p[i] && init && !kasan_has_integrated_init())
713 55179 : memset(p[i], 0, zero_size);
714 61648 : kmemleak_alloc_recursive(p[i], s->object_size, 1,
715 : s->flags, flags);
716 61648 : kmsan_slab_alloc(s, p[i], flags);
717 : }
718 :
719 61648 : memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
720 61648 : }
721 :
722 : /*
723 : * The slab lists for all objects.
724 : */
725 : struct kmem_cache_node {
726 : #ifdef CONFIG_SLAB
727 : raw_spinlock_t list_lock;
728 : struct list_head slabs_partial; /* partial list first, better asm code */
729 : struct list_head slabs_full;
730 : struct list_head slabs_free;
731 : unsigned long total_slabs; /* length of all slab lists */
732 : unsigned long free_slabs; /* length of free slab list only */
733 : unsigned long free_objects;
734 : unsigned int free_limit;
735 : unsigned int colour_next; /* Per-node cache coloring */
736 : struct array_cache *shared; /* shared per node */
737 : struct alien_cache **alien; /* on other nodes */
738 : unsigned long next_reap; /* updated without locking */
739 : int free_touched; /* updated without locking */
740 : #endif
741 :
742 : #ifdef CONFIG_SLUB
743 : spinlock_t list_lock;
744 : unsigned long nr_partial;
745 : struct list_head partial;
746 : #ifdef CONFIG_SLUB_DEBUG
747 : atomic_long_t nr_slabs;
748 : atomic_long_t total_objects;
749 : struct list_head full;
750 : #endif
751 : #endif
752 :
753 : };
754 :
755 : static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
756 : {
757 9861 : return s->node[node];
758 : }
759 :
760 : /*
761 : * Iterator over all nodes. The body will be executed for each node that has
762 : * a kmem_cache_node structure allocated (which is true for all online nodes)
763 : */
764 : #define for_each_kmem_cache_node(__s, __node, __n) \
765 : for (__node = 0; __node < nr_node_ids; __node++) \
766 : if ((__n = get_node(__s, __node)))
767 :
768 :
769 : #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
770 : void dump_unreclaimable_slab(void);
771 : #else
772 : static inline void dump_unreclaimable_slab(void)
773 : {
774 : }
775 : #endif
776 :
777 : void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
778 :
779 : #ifdef CONFIG_SLAB_FREELIST_RANDOM
780 : int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
781 : gfp_t gfp);
782 : void cache_random_seq_destroy(struct kmem_cache *cachep);
783 : #else
784 : static inline int cache_random_seq_create(struct kmem_cache *cachep,
785 : unsigned int count, gfp_t gfp)
786 : {
787 : return 0;
788 : }
789 : static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
790 : #endif /* CONFIG_SLAB_FREELIST_RANDOM */
791 :
792 : static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c)
793 : {
794 61648 : if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
795 : &init_on_alloc)) {
796 0 : if (c->ctor)
797 : return false;
798 0 : if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))
799 0 : return flags & __GFP_ZERO;
800 : return true;
801 : }
802 61648 : return flags & __GFP_ZERO;
803 : }
804 :
805 : static inline bool slab_want_init_on_free(struct kmem_cache *c)
806 : {
807 110707 : if (static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
808 : &init_on_free))
809 0 : return !(c->ctor ||
810 0 : (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)));
811 : return false;
812 : }
813 :
814 : #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG)
815 : void debugfs_slab_release(struct kmem_cache *);
816 : #else
817 : static inline void debugfs_slab_release(struct kmem_cache *s) { }
818 : #endif
819 :
820 : #ifdef CONFIG_PRINTK
821 : #define KS_ADDRS_COUNT 16
822 : struct kmem_obj_info {
823 : void *kp_ptr;
824 : struct slab *kp_slab;
825 : void *kp_objp;
826 : unsigned long kp_data_offset;
827 : struct kmem_cache *kp_slab_cache;
828 : void *kp_ret;
829 : void *kp_stack[KS_ADDRS_COUNT];
830 : void *kp_free_stack[KS_ADDRS_COUNT];
831 : };
832 : void __kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab);
833 : #endif
834 :
835 : #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
836 : void __check_heap_object(const void *ptr, unsigned long n,
837 : const struct slab *slab, bool to_user);
838 : #else
839 : static inline
840 : void __check_heap_object(const void *ptr, unsigned long n,
841 : const struct slab *slab, bool to_user)
842 : {
843 : }
844 : #endif
845 :
846 : #ifdef CONFIG_SLUB_DEBUG
847 : void skip_orig_size_check(struct kmem_cache *s, const void *object);
848 : #endif
849 :
850 : #endif /* MM_SLAB_H */
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