1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
4 *
5 * (C) SGI 2006, Christoph Lameter
6 * Cleaned up and restructured to ease the addition of alternative
7 * implementations of SLAB allocators.
8 * (C) Linux Foundation 2008-2013
9 * Unified interface for all slab allocators
10 */
11
12 #ifndef _LINUX_SLAB_H
13 #define _LINUX_SLAB_H
14
15 #include <linux/gfp.h>
16 #include <linux/types.h>
17 #include <linux/workqueue.h>
18
19
20 /*
21 * Flags to pass to kmem_cache_create().
22 * The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
23 */
24 /* DEBUG: Perform (expensive) checks on alloc/free */
25 #define SLAB_CONSISTENCY_CHECKS ((slab_flags_t __force)0x00000100U)
26 /* DEBUG: Red zone objs in a cache */
27 #define SLAB_RED_ZONE ((slab_flags_t __force)0x00000400U)
28 /* DEBUG: Poison objects */
29 #define SLAB_POISON ((slab_flags_t __force)0x00000800U)
30 /* Align objs on cache lines */
31 #define SLAB_HWCACHE_ALIGN ((slab_flags_t __force)0x00002000U)
32 /* Use GFP_DMA memory */
33 #define SLAB_CACHE_DMA ((slab_flags_t __force)0x00004000U)
34 /* DEBUG: Store the last owner for bug hunting */
35 #define SLAB_STORE_USER ((slab_flags_t __force)0x00010000U)
36 /* Panic if kmem_cache_create() fails */
37 #define SLAB_PANIC ((slab_flags_t __force)0x00040000U)
38 /*
39 * SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
40 *
41 * This delays freeing the SLAB page by a grace period, it does _NOT_
42 * delay object freeing. This means that if you do kmem_cache_free()
43 * that memory location is free to be reused at any time. Thus it may
44 * be possible to see another object there in the same RCU grace period.
45 *
46 * This feature only ensures the memory location backing the object
47 * stays valid, the trick to using this is relying on an independent
48 * object validation pass. Something like:
49 *
50 * rcu_read_lock()
51 * again:
52 * obj = lockless_lookup(key);
53 * if (obj) {
54 * if (!try_get_ref(obj)) // might fail for free objects
55 * goto again;
56 *
57 * if (obj->key != key) { // not the object we expected
58 * put_ref(obj);
59 * goto again;
60 * }
61 * }
62 * rcu_read_unlock();
63 *
64 * This is useful if we need to approach a kernel structure obliquely,
65 * from its address obtained without the usual locking. We can lock
66 * the structure to stabilize it and check it's still at the given address,
67 * only if we can be sure that the memory has not been meanwhile reused
68 * for some other kind of object (which our subsystem's lock might corrupt).
69 *
70 * rcu_read_lock before reading the address, then rcu_read_unlock after
71 * taking the spinlock within the structure expected at that address.
72 *
73 * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
74 */
75 /* Defer freeing slabs to RCU */
76 #define SLAB_TYPESAFE_BY_RCU ((slab_flags_t __force)0x00080000U)
77 /* Spread some memory over cpuset */
78 #define SLAB_MEM_SPREAD ((slab_flags_t __force)0x00100000U)
79 /* Trace allocations and frees */
80 #define SLAB_TRACE ((slab_flags_t __force)0x00200000U)
81
82 /* Flag to prevent checks on free */
83 #ifdef CONFIG_DEBUG_OBJECTS
84 # define SLAB_DEBUG_OBJECTS ((slab_flags_t __force)0x00400000U)
85 #else
86 # define SLAB_DEBUG_OBJECTS 0
87 #endif
88
89 /* Avoid kmemleak tracing */
90 #define SLAB_NOLEAKTRACE ((slab_flags_t __force)0x00800000U)
91
92 /* Fault injection mark */
93 #ifdef CONFIG_FAILSLAB
94 # define SLAB_FAILSLAB ((slab_flags_t __force)0x02000000U)
95 #else
96 # define SLAB_FAILSLAB 0
97 #endif
98 /* Account to memcg */
99 #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
100 # define SLAB_ACCOUNT ((slab_flags_t __force)0x04000000U)
101 #else
102 # define SLAB_ACCOUNT 0
103 #endif
104
105 #ifdef CONFIG_KASAN
106 #define SLAB_KASAN ((slab_flags_t __force)0x08000000U)
107 #else
108 #define SLAB_KASAN 0
109 #endif
110
111 /* The following flags affect the page allocator grouping pages by mobility */
112 /* Objects are reclaimable */
113 #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U)
114 #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
115 /*
116 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
117 *
118 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
119 *
120 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
121 * Both make kfree a no-op.
122 */
123 #define ZERO_SIZE_PTR ((void *)16)
124
125 #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
126 (unsigned long)ZERO_SIZE_PTR)
127
128 #include <linux/kmemleak.h>
129 #include <linux/kasan.h>
130
131 struct mem_cgroup;
132 /*
133 * struct kmem_cache related prototypes
134 */
135 void __init kmem_cache_init(void);
136 bool slab_is_available(void);
137
138 extern bool usercopy_fallback;
139
140 struct kmem_cache *kmem_cache_create(const char *name, size_t size,
141 size_t align, slab_flags_t flags,
142 void (*ctor)(void *));
143 struct kmem_cache *kmem_cache_create_usercopy(const char *name,
144 size_t size, size_t align, slab_flags_t flags,
145 size_t useroffset, size_t usersize,
146 void (*ctor)(void *));
147 void kmem_cache_destroy(struct kmem_cache *);
148 int kmem_cache_shrink(struct kmem_cache *);
149
150 void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *);
151 void memcg_deactivate_kmem_caches(struct mem_cgroup *);
152 void memcg_destroy_kmem_caches(struct mem_cgroup *);
153
154 /*
155 * Please use this macro to create slab caches. Simply specify the
156 * name of the structure and maybe some flags that are listed above.
157 *
158 * The alignment of the struct determines object alignment. If you
159 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
160 * then the objects will be properly aligned in SMP configurations.
161 */
162 #define KMEM_CACHE(__struct, __flags) \
163 kmem_cache_create(#__struct, sizeof(struct __struct), \
164 __alignof__(struct __struct), (__flags), NULL)
165
166 /*
167 * To whitelist a single field for copying to/from usercopy, use this
168 * macro instead for KMEM_CACHE() above.
169 */
170 #define KMEM_CACHE_USERCOPY(__struct, __flags, __field) \
171 kmem_cache_create_usercopy(#__struct, \
172 sizeof(struct __struct), \
173 __alignof__(struct __struct), (__flags), \
174 offsetof(struct __struct, __field), \
175 sizeof_field(struct __struct, __field), NULL)
176
177 /*
178 * Common kmalloc functions provided by all allocators
179 */
180 void * __must_check __krealloc(const void *, size_t, gfp_t);
181 void * __must_check krealloc(const void *, size_t, gfp_t);
182 void kfree(const void *);
183 void kzfree(const void *);
184 size_t ksize(const void *);
185
186 #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
187 void __check_heap_object(const void *ptr, unsigned long n, struct page *page,
188 bool to_user);
189 #else
190 static inline void __check_heap_object(const void *ptr, unsigned long n,
191 struct page *page, bool to_user) { }
192 #endif
193
194 /*
195 * Some archs want to perform DMA into kmalloc caches and need a guaranteed
196 * alignment larger than the alignment of a 64-bit integer.
197 * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
198 */
199 #if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
200 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
201 #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
202 #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
203 #else
204 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
205 #endif
206
207 /*
208 * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
209 * Intended for arches that get misalignment faults even for 64 bit integer
210 * aligned buffers.
211 */
212 #ifndef ARCH_SLAB_MINALIGN
213 #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
214 #endif
215
216 /*
217 * kmalloc and friends return ARCH_KMALLOC_MINALIGN aligned
218 * pointers. kmem_cache_alloc and friends return ARCH_SLAB_MINALIGN
219 * aligned pointers.
220 */
221 #define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
222 #define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
223 #define __assume_page_alignment __assume_aligned(PAGE_SIZE)
224
225 /*
226 * Kmalloc array related definitions
227 */
228
229 #ifdef CONFIG_SLAB
230 /*
231 * The largest kmalloc size supported by the SLAB allocators is
232 * 32 megabyte (2^25) or the maximum allocatable page order if that is
233 * less than 32 MB.
234 *
235 * WARNING: Its not easy to increase this value since the allocators have
236 * to do various tricks to work around compiler limitations in order to
237 * ensure proper constant folding.
238 */
239 #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
240 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
241 #define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH
242 #ifndef KMALLOC_SHIFT_LOW
243 #define KMALLOC_SHIFT_LOW 5
244 #endif
245 #endif
246
247 #ifdef CONFIG_SLUB
248 /*
249 * SLUB directly allocates requests fitting in to an order-1 page
250 * (PAGE_SIZE*2). Larger requests are passed to the page allocator.
251 */
252 #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
253 #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
254 #ifndef KMALLOC_SHIFT_LOW
255 #define KMALLOC_SHIFT_LOW 3
256 #endif
257 #endif
258
259 #ifdef CONFIG_SLOB
260 /*
261 * SLOB passes all requests larger than one page to the page allocator.
262 * No kmalloc array is necessary since objects of different sizes can
263 * be allocated from the same page.
264 */
265 #define KMALLOC_SHIFT_HIGH PAGE_SHIFT
266 #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
267 #ifndef KMALLOC_SHIFT_LOW
268 #define KMALLOC_SHIFT_LOW 3
269 #endif
270 #endif
271
272 /* Maximum allocatable size */
273 #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
274 /* Maximum size for which we actually use a slab cache */
275 #define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
276 /* Maximum order allocatable via the slab allocagtor */
277 #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
278
279 /*
280 * Kmalloc subsystem.
281 */
282 #ifndef KMALLOC_MIN_SIZE
283 #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
284 #endif
285
286 /*
287 * This restriction comes from byte sized index implementation.
288 * Page size is normally 2^12 bytes and, in this case, if we want to use
289 * byte sized index which can represent 2^8 entries, the size of the object
290 * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
291 * If minimum size of kmalloc is less than 16, we use it as minimum object
292 * size and give up to use byte sized index.
293 */
294 #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
295 (KMALLOC_MIN_SIZE) : 16)
296
297 #ifndef CONFIG_SLOB
298 extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
299 #ifdef CONFIG_ZONE_DMA
300 extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
301 #endif
302
303 /*
304 * Figure out which kmalloc slab an allocation of a certain size
305 * belongs to.
306 * 0 = zero alloc
307 * 1 = 65 .. 96 bytes
308 * 2 = 129 .. 192 bytes
309 * n = 2^(n-1)+1 .. 2^n
310 */
311 static __always_inline int kmalloc_index(size_t size)
312 {
313 if (!size)
314 return 0;
315
316 if (size <= KMALLOC_MIN_SIZE)
317 return KMALLOC_SHIFT_LOW;
318
319 if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
320 return 1;
321 if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
322 return 2;
323 if (size <= 8) return 3;
324 if (size <= 16) return 4;
325 if (size <= 32) return 5;
326 if (size <= 64) return 6;
327 if (size <= 128) return 7;
328 if (size <= 256) return 8;
329 if (size <= 512) return 9;
330 if (size <= 1024) return 10;
331 if (size <= 2 * 1024) return 11;
332 if (size <= 4 * 1024) return 12;
333 if (size <= 8 * 1024) return 13;
334 if (size <= 16 * 1024) return 14;
335 if (size <= 32 * 1024) return 15;
336 if (size <= 64 * 1024) return 16;
337 if (size <= 128 * 1024) return 17;
338 if (size <= 256 * 1024) return 18;
339 if (size <= 512 * 1024) return 19;
340 if (size <= 1024 * 1024) return 20;
341 if (size <= 2 * 1024 * 1024) return 21;
342 if (size <= 4 * 1024 * 1024) return 22;
343 if (size <= 8 * 1024 * 1024) return 23;
344 if (size <= 16 * 1024 * 1024) return 24;
345 if (size <= 32 * 1024 * 1024) return 25;
346 if (size <= 64 * 1024 * 1024) return 26;
347 BUG();
348
349 /* Will never be reached. Needed because the compiler may complain */
350 return -1;
351 }
352 #endif /* !CONFIG_SLOB */
353
354 void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc;
355 void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc;
356 void kmem_cache_free(struct kmem_cache *, void *);
357
358 /*
359 * Bulk allocation and freeing operations. These are accelerated in an
360 * allocator specific way to avoid taking locks repeatedly or building
361 * metadata structures unnecessarily.
362 *
363 * Note that interrupts must be enabled when calling these functions.
364 */
365 void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
366 int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
367
368 /*
369 * Caller must not use kfree_bulk() on memory not originally allocated
370 * by kmalloc(), because the SLOB allocator cannot handle this.
371 */
372 static __always_inline void kfree_bulk(size_t size, void **p)
373 {
374 kmem_cache_free_bulk(NULL, size, p);
375 }
376
377 #ifdef CONFIG_NUMA
378 void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc;
379 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc;
380 #else
381 static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
382 {
383 return __kmalloc(size, flags);
384 }
385
386 static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
387 {
388 return kmem_cache_alloc(s, flags);
389 }
390 #endif
391
392 #ifdef CONFIG_TRACING
393 extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc;
394
395 #ifdef CONFIG_NUMA
396 extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
397 gfp_t gfpflags,
398 int node, size_t size) __assume_slab_alignment __malloc;
399 #else
400 static __always_inline void *
401 kmem_cache_alloc_node_trace(struct kmem_cache *s,
402 gfp_t gfpflags,
403 int node, size_t size)
404 {
405 return kmem_cache_alloc_trace(s, gfpflags, size);
406 }
407 #endif /* CONFIG_NUMA */
408
409 #else /* CONFIG_TRACING */
410 static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
411 gfp_t flags, size_t size)
412 {
413 void *ret = kmem_cache_alloc(s, flags);
414
415 kasan_kmalloc(s, ret, size, flags);
416 return ret;
417 }
418
419 static __always_inline void *
420 kmem_cache_alloc_node_trace(struct kmem_cache *s,
421 gfp_t gfpflags,
422 int node, size_t size)
423 {
424 void *ret = kmem_cache_alloc_node(s, gfpflags, node);
425
426 kasan_kmalloc(s, ret, size, gfpflags);
427 return ret;
428 }
429 #endif /* CONFIG_TRACING */
430
431 extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
432
433 #ifdef CONFIG_TRACING
434 extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
435 #else
436 static __always_inline void *
437 kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
438 {
439 return kmalloc_order(size, flags, order);
440 }
441 #endif
442
443 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
444 {
445 unsigned int order = get_order(size);
446 return kmalloc_order_trace(size, flags, order);
447 }
448
449 /**
450 * kmalloc - allocate memory
451 * @size: how many bytes of memory are required.
452 * @flags: the type of memory to allocate.
453 *
454 * kmalloc is the normal method of allocating memory
455 * for objects smaller than page size in the kernel.
456 *
457 * The @flags argument may be one of:
458 *
459 * %GFP_USER - Allocate memory on behalf of user. May sleep.
460 *
461 * %GFP_KERNEL - Allocate normal kernel ram. May sleep.
462 *
463 * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools.
464 * For example, use this inside interrupt handlers.
465 *
466 * %GFP_HIGHUSER - Allocate pages from high memory.
467 *
468 * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
469 *
470 * %GFP_NOFS - Do not make any fs calls while trying to get memory.
471 *
472 * %GFP_NOWAIT - Allocation will not sleep.
473 *
474 * %__GFP_THISNODE - Allocate node-local memory only.
475 *
476 * %GFP_DMA - Allocation suitable for DMA.
477 * Should only be used for kmalloc() caches. Otherwise, use a
478 * slab created with SLAB_DMA.
479 *
480 * Also it is possible to set different flags by OR'ing
481 * in one or more of the following additional @flags:
482 *
483 * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
484 *
485 * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
486 * (think twice before using).
487 *
488 * %__GFP_NORETRY - If memory is not immediately available,
489 * then give up at once.
490 *
491 * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
492 *
493 * %__GFP_RETRY_MAYFAIL - Try really hard to succeed the allocation but fail
494 * eventually.
495 *
496 * There are other flags available as well, but these are not intended
497 * for general use, and so are not documented here. For a full list of
498 * potential flags, always refer to linux/gfp.h.
499 */
500 static __always_inline void *kmalloc(size_t size, gfp_t flags)
501 {
502 if (__builtin_constant_p(size)) {
503 if (size > KMALLOC_MAX_CACHE_SIZE)
504 return kmalloc_large(size, flags);
505 #ifndef CONFIG_SLOB
506 if (!(flags & GFP_DMA)) {
507 int index = kmalloc_index(size);
508
509 if (!index)
510 return ZERO_SIZE_PTR;
511
512 return kmem_cache_alloc_trace(kmalloc_caches[index],
513 flags, size);
514 }
515 #endif
516 }
517 return __kmalloc(size, flags);
518 }
519
520 /*
521 * Determine size used for the nth kmalloc cache.
522 * return size or 0 if a kmalloc cache for that
523 * size does not exist
524 */
525 static __always_inline int kmalloc_size(int n)
526 {
527 #ifndef CONFIG_SLOB
528 if (n > 2)
529 return 1 << n;
530
531 if (n == 1 && KMALLOC_MIN_SIZE <= 32)
532 return 96;
533
534 if (n == 2 && KMALLOC_MIN_SIZE <= 64)
535 return 192;
536 #endif
537 return 0;
538 }
539
540 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
541 {
542 #ifndef CONFIG_SLOB
543 if (__builtin_constant_p(size) &&
544 size <= KMALLOC_MAX_CACHE_SIZE && !(flags & GFP_DMA)) {
545 int i = kmalloc_index(size);
546
547 if (!i)
548 return ZERO_SIZE_PTR;
549
550 return kmem_cache_alloc_node_trace(kmalloc_caches[i],
551 flags, node, size);
552 }
553 #endif
554 return __kmalloc_node(size, flags, node);
555 }
556
557 struct memcg_cache_array {
558 struct rcu_head rcu;
559 struct kmem_cache *entries[0];
560 };
561
562 /*
563 * This is the main placeholder for memcg-related information in kmem caches.
564 * Both the root cache and the child caches will have it. For the root cache,
565 * this will hold a dynamically allocated array large enough to hold
566 * information about the currently limited memcgs in the system. To allow the
567 * array to be accessed without taking any locks, on relocation we free the old
568 * version only after a grace period.
569 *
570 * Root and child caches hold different metadata.
571 *
572 * @root_cache: Common to root and child caches. NULL for root, pointer to
573 * the root cache for children.
574 *
575 * The following fields are specific to root caches.
576 *
577 * @memcg_caches: kmemcg ID indexed table of child caches. This table is
578 * used to index child cachces during allocation and cleared
579 * early during shutdown.
580 *
581 * @root_caches_node: List node for slab_root_caches list.
582 *
583 * @children: List of all child caches. While the child caches are also
584 * reachable through @memcg_caches, a child cache remains on
585 * this list until it is actually destroyed.
586 *
587 * The following fields are specific to child caches.
588 *
589 * @memcg: Pointer to the memcg this cache belongs to.
590 *
591 * @children_node: List node for @root_cache->children list.
592 *
593 * @kmem_caches_node: List node for @memcg->kmem_caches list.
594 */
595 struct memcg_cache_params {
596 struct kmem_cache *root_cache;
597 union {
598 struct {
599 struct memcg_cache_array __rcu *memcg_caches;
600 struct list_head __root_caches_node;
601 struct list_head children;
602 };
603 struct {
604 struct mem_cgroup *memcg;
605 struct list_head children_node;
606 struct list_head kmem_caches_node;
607
608 void (*deact_fn)(struct kmem_cache *);
609 union {
610 struct rcu_head deact_rcu_head;
611 struct work_struct deact_work;
612 };
613 };
614 };
615 };
616
617 int memcg_update_all_caches(int num_memcgs);
618
619 /**
620 * kmalloc_array - allocate memory for an array.
621 * @n: number of elements.
622 * @size: element size.
623 * @flags: the type of memory to allocate (see kmalloc).
624 */
625 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
626 {
627 if (size != 0 && n > SIZE_MAX / size)
628 return NULL;
629 if (__builtin_constant_p(n) && __builtin_constant_p(size))
630 return kmalloc(n * size, flags);
631 return __kmalloc(n * size, flags);
632 }
633
634 /**
635 * kcalloc - allocate memory for an array. The memory is set to zero.
636 * @n: number of elements.
637 * @size: element size.
638 * @flags: the type of memory to allocate (see kmalloc).
639 */
640 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
641 {
642 return kmalloc_array(n, size, flags | __GFP_ZERO);
643 }
644
645 /*
646 * kmalloc_track_caller is a special version of kmalloc that records the
647 * calling function of the routine calling it for slab leak tracking instead
648 * of just the calling function (confusing, eh?).
649 * It's useful when the call to kmalloc comes from a widely-used standard
650 * allocator where we care about the real place the memory allocation
651 * request comes from.
652 */
653 extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
654 #define kmalloc_track_caller(size, flags) \
655 __kmalloc_track_caller(size, flags, _RET_IP_)
656
657 static inline void *kmalloc_array_node(size_t n, size_t size, gfp_t flags,
658 int node)
659 {
660 if (size != 0 && n > SIZE_MAX / size)
661 return NULL;
662 if (__builtin_constant_p(n) && __builtin_constant_p(size))
663 return kmalloc_node(n * size, flags, node);
664 return __kmalloc_node(n * size, flags, node);
665 }
666
667 static inline void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node)
668 {
669 return kmalloc_array_node(n, size, flags | __GFP_ZERO, node);
670 }
671
672
673 #ifdef CONFIG_NUMA
674 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
675 #define kmalloc_node_track_caller(size, flags, node) \
676 __kmalloc_node_track_caller(size, flags, node, \
677 _RET_IP_)
678
679 #else /* CONFIG_NUMA */
680
681 #define kmalloc_node_track_caller(size, flags, node) \
682 kmalloc_track_caller(size, flags)
683
684 #endif /* CONFIG_NUMA */
685
686 /*
687 * Shortcuts
688 */
689 static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
690 {
691 return kmem_cache_alloc(k, flags | __GFP_ZERO);
692 }
693
694 /**
695 * kzalloc - allocate memory. The memory is set to zero.
696 * @size: how many bytes of memory are required.
697 * @flags: the type of memory to allocate (see kmalloc).
698 */
699 static inline void *kzalloc(size_t size, gfp_t flags)
700 {
701 return kmalloc(size, flags | __GFP_ZERO);
702 }
703
704 /**
705 * kzalloc_node - allocate zeroed memory from a particular memory node.
706 * @size: how many bytes of memory are required.
707 * @flags: the type of memory to allocate (see kmalloc).
708 * @node: memory node from which to allocate
709 */
710 static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
711 {
712 return kmalloc_node(size, flags | __GFP_ZERO, node);
713 }
714
715 unsigned int kmem_cache_size(struct kmem_cache *s);
716 void __init kmem_cache_init_late(void);
717
718 #if defined(CONFIG_SMP) && defined(CONFIG_SLAB)
719 int slab_prepare_cpu(unsigned int cpu);
720 int slab_dead_cpu(unsigned int cpu);
721 #else
722 #define slab_prepare_cpu NULL
723 #define slab_dead_cpu NULL
724 #endif
725
726 #endif /* _LINUX_SLAB_H */
727
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