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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Written by Mark Hemment, 1996 ([email protected]).
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/overflow.h>
17#include <linux/types.h>
18#include <linux/workqueue.h>
19#include <linux/percpu-refcount.h>
20
21
22/*
23 * Flags to pass to kmem_cache_create().
24 * The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
25 */
26/* DEBUG: Perform (expensive) checks on alloc/free */
27#define SLAB_CONSISTENCY_CHECKS ((slab_flags_t __force)0x00000100U)
28/* DEBUG: Red zone objs in a cache */
29#define SLAB_RED_ZONE ((slab_flags_t __force)0x00000400U)
30/* DEBUG: Poison objects */
31#define SLAB_POISON ((slab_flags_t __force)0x00000800U)
32/* Align objs on cache lines */
33#define SLAB_HWCACHE_ALIGN ((slab_flags_t __force)0x00002000U)
34/* Use GFP_DMA memory */
35#define SLAB_CACHE_DMA ((slab_flags_t __force)0x00004000U)
36/* Use GFP_DMA32 memory */
37#define SLAB_CACHE_DMA32 ((slab_flags_t __force)0x00008000U)
38/* DEBUG: Store the last owner for bug hunting */
39#define SLAB_STORE_USER ((slab_flags_t __force)0x00010000U)
40/* Panic if kmem_cache_create() fails */
41#define SLAB_PANIC ((slab_flags_t __force)0x00040000U)
42/*
43 * SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
44 *
45 * This delays freeing the SLAB page by a grace period, it does _NOT_
46 * delay object freeing. This means that if you do kmem_cache_free()
47 * that memory location is free to be reused at any time. Thus it may
48 * be possible to see another object there in the same RCU grace period.
49 *
50 * This feature only ensures the memory location backing the object
51 * stays valid, the trick to using this is relying on an independent
52 * object validation pass. Something like:
53 *
54 * rcu_read_lock()
55 * again:
56 * obj = lockless_lookup(key);
57 * if (obj) {
58 * if (!try_get_ref(obj)) // might fail for free objects
59 * goto again;
60 *
61 * if (obj->key != key) { // not the object we expected
62 * put_ref(obj);
63 * goto again;
64 * }
65 * }
66 * rcu_read_unlock();
67 *
68 * This is useful if we need to approach a kernel structure obliquely,
69 * from its address obtained without the usual locking. We can lock
70 * the structure to stabilize it and check it's still at the given address,
71 * only if we can be sure that the memory has not been meanwhile reused
72 * for some other kind of object (which our subsystem's lock might corrupt).
73 *
74 * rcu_read_lock before reading the address, then rcu_read_unlock after
75 * taking the spinlock within the structure expected at that address.
76 *
77 * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
78 */
79/* Defer freeing slabs to RCU */
80#define SLAB_TYPESAFE_BY_RCU ((slab_flags_t __force)0x00080000U)
81/* Spread some memory over cpuset */
82#define SLAB_MEM_SPREAD ((slab_flags_t __force)0x00100000U)
83/* Trace allocations and frees */
84#define SLAB_TRACE ((slab_flags_t __force)0x00200000U)
85
86/* Flag to prevent checks on free */
87#ifdef CONFIG_DEBUG_OBJECTS
88# define SLAB_DEBUG_OBJECTS ((slab_flags_t __force)0x00400000U)
89#else
90# define SLAB_DEBUG_OBJECTS 0
91#endif
92
93/* Avoid kmemleak tracing */
94#define SLAB_NOLEAKTRACE ((slab_flags_t __force)0x00800000U)
95
96/* Fault injection mark */
97#ifdef CONFIG_FAILSLAB
98# define SLAB_FAILSLAB ((slab_flags_t __force)0x02000000U)
99#else
100# define SLAB_FAILSLAB 0
101#endif
102/* Account to memcg */
103#ifdef CONFIG_MEMCG_KMEM
104# define SLAB_ACCOUNT ((slab_flags_t __force)0x04000000U)
105#else
106# define SLAB_ACCOUNT 0
107#endif
108
109#ifdef CONFIG_KASAN
110#define SLAB_KASAN ((slab_flags_t __force)0x08000000U)
111#else
112#define SLAB_KASAN 0
113#endif
114
115/* The following flags affect the page allocator grouping pages by mobility */
116/* Objects are reclaimable */
117#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U)
118#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
119
120/* Slab deactivation flag */
121#define SLAB_DEACTIVATED ((slab_flags_t __force)0x10000000U)
122
123/*
124 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
125 *
126 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
127 *
128 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
129 * Both make kfree a no-op.
130 */
131#define ZERO_SIZE_PTR ((void *)16)
132
133#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
134 (unsigned long)ZERO_SIZE_PTR)
135
136#include <linux/kasan.h>
137
138struct mem_cgroup;
139/*
140 * struct kmem_cache related prototypes
141 */
142void __init kmem_cache_init(void);
143bool slab_is_available(void);
144
145extern bool usercopy_fallback;
146
147struct kmem_cache *kmem_cache_create(const char *name, unsigned int size,
148 unsigned int align, slab_flags_t flags,
149 void (*ctor)(void *));
150struct kmem_cache *kmem_cache_create_usercopy(const char *name,
151 unsigned int size, unsigned int align,
152 slab_flags_t flags,
153 unsigned int useroffset, unsigned int usersize,
154 void (*ctor)(void *));
155void kmem_cache_destroy(struct kmem_cache *);
156int kmem_cache_shrink(struct kmem_cache *);
157
158void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *);
159void memcg_deactivate_kmem_caches(struct mem_cgroup *, struct mem_cgroup *);
160
161/*
162 * Please use this macro to create slab caches. Simply specify the
163 * name of the structure and maybe some flags that are listed above.
164 *
165 * The alignment of the struct determines object alignment. If you
166 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
167 * then the objects will be properly aligned in SMP configurations.
168 */
169#define KMEM_CACHE(__struct, __flags) \
170 kmem_cache_create(#__struct, sizeof(struct __struct), \
171 __alignof__(struct __struct), (__flags), NULL)
172
173/*
174 * To whitelist a single field for copying to/from usercopy, use this
175 * macro instead for KMEM_CACHE() above.
176 */
177#define KMEM_CACHE_USERCOPY(__struct, __flags, __field) \
178 kmem_cache_create_usercopy(#__struct, \
179 sizeof(struct __struct), \
180 __alignof__(struct __struct), (__flags), \
181 offsetof(struct __struct, __field), \
182 sizeof_field(struct __struct, __field), NULL)
183
184/*
185 * Common kmalloc functions provided by all allocators
186 */
187void * __must_check krealloc(const void *, size_t, gfp_t);
188void kfree(const void *);
189void kzfree(const void *);
190size_t __ksize(const void *);
191size_t ksize(const void *);
192
193#ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
194void __check_heap_object(const void *ptr, unsigned long n, struct page *page,
195 bool to_user);
196#else
197static inline void __check_heap_object(const void *ptr, unsigned long n,
198 struct page *page, bool to_user) { }
199#endif
200
201/*
202 * Some archs want to perform DMA into kmalloc caches and need a guaranteed
203 * alignment larger than the alignment of a 64-bit integer.
204 * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
205 */
206#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
207#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
208#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
209#define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
210#else
211#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
212#endif
213
214/*
215 * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
216 * Intended for arches that get misalignment faults even for 64 bit integer
217 * aligned buffers.
218 */
219#ifndef ARCH_SLAB_MINALIGN
220#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
221#endif
222
223/*
224 * kmalloc and friends return ARCH_KMALLOC_MINALIGN aligned
225 * pointers. kmem_cache_alloc and friends return ARCH_SLAB_MINALIGN
226 * aligned pointers.
227 */
228#define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
229#define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
230#define __assume_page_alignment __assume_aligned(PAGE_SIZE)
231
232/*
233 * Kmalloc array related definitions
234 */
235
236#ifdef CONFIG_SLAB
237/*
238 * The largest kmalloc size supported by the SLAB allocators is
239 * 32 megabyte (2^25) or the maximum allocatable page order if that is
240 * less than 32 MB.
241 *
242 * WARNING: Its not easy to increase this value since the allocators have
243 * to do various tricks to work around compiler limitations in order to
244 * ensure proper constant folding.
245 */
246#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
247 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
248#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH
249#ifndef KMALLOC_SHIFT_LOW
250#define KMALLOC_SHIFT_LOW 5
251#endif
252#endif
253
254#ifdef CONFIG_SLUB
255/*
256 * SLUB directly allocates requests fitting in to an order-1 page
257 * (PAGE_SIZE*2). Larger requests are passed to the page allocator.
258 */
259#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
260#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
261#ifndef KMALLOC_SHIFT_LOW
262#define KMALLOC_SHIFT_LOW 3
263#endif
264#endif
265
266#ifdef CONFIG_SLOB
267/*
268 * SLOB passes all requests larger than one page to the page allocator.
269 * No kmalloc array is necessary since objects of different sizes can
270 * be allocated from the same page.
271 */
272#define KMALLOC_SHIFT_HIGH PAGE_SHIFT
273#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
274#ifndef KMALLOC_SHIFT_LOW
275#define KMALLOC_SHIFT_LOW 3
276#endif
277#endif
278
279/* Maximum allocatable size */
280#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
281/* Maximum size for which we actually use a slab cache */
282#define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
283/* Maximum order allocatable via the slab allocagtor */
284#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
285
286/*
287 * Kmalloc subsystem.
288 */
289#ifndef KMALLOC_MIN_SIZE
290#define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
291#endif
292
293/*
294 * This restriction comes from byte sized index implementation.
295 * Page size is normally 2^12 bytes and, in this case, if we want to use
296 * byte sized index which can represent 2^8 entries, the size of the object
297 * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
298 * If minimum size of kmalloc is less than 16, we use it as minimum object
299 * size and give up to use byte sized index.
300 */
301#define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
302 (KMALLOC_MIN_SIZE) : 16)
303
304/*
305 * Whenever changing this, take care of that kmalloc_type() and
306 * create_kmalloc_caches() still work as intended.
307 */
308enum kmalloc_cache_type {
309 KMALLOC_NORMAL = 0,
310 KMALLOC_RECLAIM,
311#ifdef CONFIG_ZONE_DMA
312 KMALLOC_DMA,
313#endif
314 NR_KMALLOC_TYPES
315};
316
317#ifndef CONFIG_SLOB
318extern struct kmem_cache *
319kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1];
320
321static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags)
322{
323#ifdef CONFIG_ZONE_DMA
324 /*
325 * The most common case is KMALLOC_NORMAL, so test for it
326 * with a single branch for both flags.
327 */
328 if (likely((flags & (__GFP_DMA | __GFP_RECLAIMABLE)) == 0))
329 return KMALLOC_NORMAL;
330
331 /*
332 * At least one of the flags has to be set. If both are, __GFP_DMA
333 * is more important.
334 */
335 return flags & __GFP_DMA ? KMALLOC_DMA : KMALLOC_RECLAIM;
336#else
337 return flags & __GFP_RECLAIMABLE ? KMALLOC_RECLAIM : KMALLOC_NORMAL;
338#endif
339}
340
341/*
342 * Figure out which kmalloc slab an allocation of a certain size
343 * belongs to.
344 * 0 = zero alloc
345 * 1 = 65 .. 96 bytes
346 * 2 = 129 .. 192 bytes
347 * n = 2^(n-1)+1 .. 2^n
348 */
349static __always_inline unsigned int kmalloc_index(size_t size)
350{
351 if (!size)
352 return 0;
353
354 if (size <= KMALLOC_MIN_SIZE)
355 return KMALLOC_SHIFT_LOW;
356
357 if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
358 return 1;
359 if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
360 return 2;
361 if (size <= 8) return 3;
362 if (size <= 16) return 4;
363 if (size <= 32) return 5;
364 if (size <= 64) return 6;
365 if (size <= 128) return 7;
366 if (size <= 256) return 8;
367 if (size <= 512) return 9;
368 if (size <= 1024) return 10;
369 if (size <= 2 * 1024) return 11;
370 if (size <= 4 * 1024) return 12;
371 if (size <= 8 * 1024) return 13;
372 if (size <= 16 * 1024) return 14;
373 if (size <= 32 * 1024) return 15;
374 if (size <= 64 * 1024) return 16;
375 if (size <= 128 * 1024) return 17;
376 if (size <= 256 * 1024) return 18;
377 if (size <= 512 * 1024) return 19;
378 if (size <= 1024 * 1024) return 20;
379 if (size <= 2 * 1024 * 1024) return 21;
380 if (size <= 4 * 1024 * 1024) return 22;
381 if (size <= 8 * 1024 * 1024) return 23;
382 if (size <= 16 * 1024 * 1024) return 24;
383 if (size <= 32 * 1024 * 1024) return 25;
384 if (size <= 64 * 1024 * 1024) return 26;
385 BUG();
386
387 /* Will never be reached. Needed because the compiler may complain */
388 return -1;
389}
390#endif /* !CONFIG_SLOB */
391
392void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc;
393void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc;
394void kmem_cache_free(struct kmem_cache *, void *);
395
396/*
397 * Bulk allocation and freeing operations. These are accelerated in an
398 * allocator specific way to avoid taking locks repeatedly or building
399 * metadata structures unnecessarily.
400 *
401 * Note that interrupts must be enabled when calling these functions.
402 */
403void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
404int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
405
406/*
407 * Caller must not use kfree_bulk() on memory not originally allocated
408 * by kmalloc(), because the SLOB allocator cannot handle this.
409 */
410static __always_inline void kfree_bulk(size_t size, void **p)
411{
412 kmem_cache_free_bulk(NULL, size, p);
413}
414
415#ifdef CONFIG_NUMA
416void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc;
417void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc;
418#else
419static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
420{
421 return __kmalloc(size, flags);
422}
423
424static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
425{
426 return kmem_cache_alloc(s, flags);
427}
428#endif
429
430#ifdef CONFIG_TRACING
431extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc;
432
433#ifdef CONFIG_NUMA
434extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
435 gfp_t gfpflags,
436 int node, size_t size) __assume_slab_alignment __malloc;
437#else
438static __always_inline void *
439kmem_cache_alloc_node_trace(struct kmem_cache *s,
440 gfp_t gfpflags,
441 int node, size_t size)
442{
443 return kmem_cache_alloc_trace(s, gfpflags, size);
444}
445#endif /* CONFIG_NUMA */
446
447#else /* CONFIG_TRACING */
448static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
449 gfp_t flags, size_t size)
450{
451 void *ret = kmem_cache_alloc(s, flags);
452
453 ret = kasan_kmalloc(s, ret, size, flags);
454 return ret;
455}
456
457static __always_inline void *
458kmem_cache_alloc_node_trace(struct kmem_cache *s,
459 gfp_t gfpflags,
460 int node, size_t size)
461{
462 void *ret = kmem_cache_alloc_node(s, gfpflags, node);
463
464 ret = kasan_kmalloc(s, ret, size, gfpflags);
465 return ret;
466}
467#endif /* CONFIG_TRACING */
468
469extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
470
471#ifdef CONFIG_TRACING
472extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
473#else
474static __always_inline void *
475kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
476{
477 return kmalloc_order(size, flags, order);
478}
479#endif
480
481static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
482{
483 unsigned int order = get_order(size);
484 return kmalloc_order_trace(size, flags, order);
485}
486
487/**
488 * kmalloc - allocate memory
489 * @size: how many bytes of memory are required.
490 * @flags: the type of memory to allocate.
491 *
492 * kmalloc is the normal method of allocating memory
493 * for objects smaller than page size in the kernel.
494 *
495 * The allocated object address is aligned to at least ARCH_KMALLOC_MINALIGN
496 * bytes. For @size of power of two bytes, the alignment is also guaranteed
497 * to be at least to the size.
498 *
499 * The @flags argument may be one of the GFP flags defined at
500 * include/linux/gfp.h and described at
501 * :ref:`Documentation/core-api/mm-api.rst <mm-api-gfp-flags>`
502 *
503 * The recommended usage of the @flags is described at
504 * :ref:`Documentation/core-api/memory-allocation.rst <memory_allocation>`
505 *
506 * Below is a brief outline of the most useful GFP flags
507 *
508 * %GFP_KERNEL
509 * Allocate normal kernel ram. May sleep.
510 *
511 * %GFP_NOWAIT
512 * Allocation will not sleep.
513 *
514 * %GFP_ATOMIC
515 * Allocation will not sleep. May use emergency pools.
516 *
517 * %GFP_HIGHUSER
518 * Allocate memory from high memory on behalf of user.
519 *
520 * Also it is possible to set different flags by OR'ing
521 * in one or more of the following additional @flags:
522 *
523 * %__GFP_HIGH
524 * This allocation has high priority and may use emergency pools.
525 *
526 * %__GFP_NOFAIL
527 * Indicate that this allocation is in no way allowed to fail
528 * (think twice before using).
529 *
530 * %__GFP_NORETRY
531 * If memory is not immediately available,
532 * then give up at once.
533 *
534 * %__GFP_NOWARN
535 * If allocation fails, don't issue any warnings.
536 *
537 * %__GFP_RETRY_MAYFAIL
538 * Try really hard to succeed the allocation but fail
539 * eventually.
540 */
541static __always_inline void *kmalloc(size_t size, gfp_t flags)
542{
543 if (__builtin_constant_p(size)) {
544#ifndef CONFIG_SLOB
545 unsigned int index;
546#endif
547 if (size > KMALLOC_MAX_CACHE_SIZE)
548 return kmalloc_large(size, flags);
549#ifndef CONFIG_SLOB
550 index = kmalloc_index(size);
551
552 if (!index)
553 return ZERO_SIZE_PTR;
554
555 return kmem_cache_alloc_trace(
556 kmalloc_caches[kmalloc_type(flags)][index],
557 flags, size);
558#endif
559 }
560 return __kmalloc(size, flags);
561}
562
563static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
564{
565#ifndef CONFIG_SLOB
566 if (__builtin_constant_p(size) &&
567 size <= KMALLOC_MAX_CACHE_SIZE) {
568 unsigned int i = kmalloc_index(size);
569
570 if (!i)
571 return ZERO_SIZE_PTR;
572
573 return kmem_cache_alloc_node_trace(
574 kmalloc_caches[kmalloc_type(flags)][i],
575 flags, node, size);
576 }
577#endif
578 return __kmalloc_node(size, flags, node);
579}
580
581int memcg_update_all_caches(int num_memcgs);
582
583/**
584 * kmalloc_array - allocate memory for an array.
585 * @n: number of elements.
586 * @size: element size.
587 * @flags: the type of memory to allocate (see kmalloc).
588 */
589static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
590{
591 size_t bytes;
592
593 if (unlikely(check_mul_overflow(n, size, &bytes)))
594 return NULL;
595 if (__builtin_constant_p(n) && __builtin_constant_p(size))
596 return kmalloc(bytes, flags);
597 return __kmalloc(bytes, flags);
598}
599
600/**
601 * kcalloc - allocate memory for an array. The memory is set to zero.
602 * @n: number of elements.
603 * @size: element size.
604 * @flags: the type of memory to allocate (see kmalloc).
605 */
606static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
607{
608 return kmalloc_array(n, size, flags | __GFP_ZERO);
609}
610
611/*
612 * kmalloc_track_caller is a special version of kmalloc that records the
613 * calling function of the routine calling it for slab leak tracking instead
614 * of just the calling function (confusing, eh?).
615 * It's useful when the call to kmalloc comes from a widely-used standard
616 * allocator where we care about the real place the memory allocation
617 * request comes from.
618 */
619extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
620#define kmalloc_track_caller(size, flags) \
621 __kmalloc_track_caller(size, flags, _RET_IP_)
622
623static inline void *kmalloc_array_node(size_t n, size_t size, gfp_t flags,
624 int node)
625{
626 size_t bytes;
627
628 if (unlikely(check_mul_overflow(n, size, &bytes)))
629 return NULL;
630 if (__builtin_constant_p(n) && __builtin_constant_p(size))
631 return kmalloc_node(bytes, flags, node);
632 return __kmalloc_node(bytes, flags, node);
633}
634
635static inline void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node)
636{
637 return kmalloc_array_node(n, size, flags | __GFP_ZERO, node);
638}
639
640
641#ifdef CONFIG_NUMA
642extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
643#define kmalloc_node_track_caller(size, flags, node) \
644 __kmalloc_node_track_caller(size, flags, node, \
645 _RET_IP_)
646
647#else /* CONFIG_NUMA */
648
649#define kmalloc_node_track_caller(size, flags, node) \
650 kmalloc_track_caller(size, flags)
651
652#endif /* CONFIG_NUMA */
653
654/*
655 * Shortcuts
656 */
657static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
658{
659 return kmem_cache_alloc(k, flags | __GFP_ZERO);
660}
661
662/**
663 * kzalloc - allocate memory. The memory is set to zero.
664 * @size: how many bytes of memory are required.
665 * @flags: the type of memory to allocate (see kmalloc).
666 */
667static inline void *kzalloc(size_t size, gfp_t flags)
668{
669 return kmalloc(size, flags | __GFP_ZERO);
670}
671
672/**
673 * kzalloc_node - allocate zeroed memory from a particular memory node.
674 * @size: how many bytes of memory are required.
675 * @flags: the type of memory to allocate (see kmalloc).
676 * @node: memory node from which to allocate
677 */
678static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
679{
680 return kmalloc_node(size, flags | __GFP_ZERO, node);
681}
682
683unsigned int kmem_cache_size(struct kmem_cache *s);
684void __init kmem_cache_init_late(void);
685
686#if defined(CONFIG_SMP) && defined(CONFIG_SLAB)
687int slab_prepare_cpu(unsigned int cpu);
688int slab_dead_cpu(unsigned int cpu);
689#else
690#define slab_prepare_cpu NULL
691#define slab_dead_cpu NULL
692#endif
693
694#endif /* _LINUX_SLAB_H */