]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - include/linux/slab.h
UBUNTU: SAUCE: LSM stacking: LSM: Manage file security blobs
[mirror_ubuntu-artful-kernel.git] / include / linux / slab.h
1 /*
2 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
3 *
4 * (C) SGI 2006, Christoph Lameter
5 * Cleaned up and restructured to ease the addition of alternative
6 * implementations of SLAB allocators.
7 * (C) Linux Foundation 2008-2013
8 * Unified interface for all slab allocators
9 */
10
11 #ifndef _LINUX_SLAB_H
12 #define _LINUX_SLAB_H
13
14 #include <linux/gfp.h>
15 #include <linux/types.h>
16 #include <linux/workqueue.h>
17
18
19 /*
20 * Flags to pass to kmem_cache_create().
21 * The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
22 */
23 #define SLAB_CONSISTENCY_CHECKS 0x00000100UL /* DEBUG: Perform (expensive) checks on alloc/free */
24 #define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */
25 #define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */
26 #define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */
27 #define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */
28 #define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */
29 #define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */
30 /*
31 * SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
32 *
33 * This delays freeing the SLAB page by a grace period, it does _NOT_
34 * delay object freeing. This means that if you do kmem_cache_free()
35 * that memory location is free to be reused at any time. Thus it may
36 * be possible to see another object there in the same RCU grace period.
37 *
38 * This feature only ensures the memory location backing the object
39 * stays valid, the trick to using this is relying on an independent
40 * object validation pass. Something like:
41 *
42 * rcu_read_lock()
43 * again:
44 * obj = lockless_lookup(key);
45 * if (obj) {
46 * if (!try_get_ref(obj)) // might fail for free objects
47 * goto again;
48 *
49 * if (obj->key != key) { // not the object we expected
50 * put_ref(obj);
51 * goto again;
52 * }
53 * }
54 * rcu_read_unlock();
55 *
56 * This is useful if we need to approach a kernel structure obliquely,
57 * from its address obtained without the usual locking. We can lock
58 * the structure to stabilize it and check it's still at the given address,
59 * only if we can be sure that the memory has not been meanwhile reused
60 * for some other kind of object (which our subsystem's lock might corrupt).
61 *
62 * rcu_read_lock before reading the address, then rcu_read_unlock after
63 * taking the spinlock within the structure expected at that address.
64 *
65 * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
66 */
67 #define SLAB_TYPESAFE_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */
68 #define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */
69 #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */
70
71 /* Flag to prevent checks on free */
72 #ifdef CONFIG_DEBUG_OBJECTS
73 # define SLAB_DEBUG_OBJECTS 0x00400000UL
74 #else
75 # define SLAB_DEBUG_OBJECTS 0x00000000UL
76 #endif
77
78 #define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */
79
80 /* Don't track use of uninitialized memory */
81 #ifdef CONFIG_KMEMCHECK
82 # define SLAB_NOTRACK 0x01000000UL
83 #else
84 # define SLAB_NOTRACK 0x00000000UL
85 #endif
86 #ifdef CONFIG_FAILSLAB
87 # define SLAB_FAILSLAB 0x02000000UL /* Fault injection mark */
88 #else
89 # define SLAB_FAILSLAB 0x00000000UL
90 #endif
91 #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
92 # define SLAB_ACCOUNT 0x04000000UL /* Account to memcg */
93 #else
94 # define SLAB_ACCOUNT 0x00000000UL
95 #endif
96
97 #ifdef CONFIG_KASAN
98 #define SLAB_KASAN 0x08000000UL
99 #else
100 #define SLAB_KASAN 0x00000000UL
101 #endif
102
103 /* The following flags affect the page allocator grouping pages by mobility */
104 #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
105 #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
106 /*
107 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
108 *
109 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
110 *
111 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
112 * Both make kfree a no-op.
113 */
114 #define ZERO_SIZE_PTR ((void *)16)
115
116 #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
117 (unsigned long)ZERO_SIZE_PTR)
118
119 #include <linux/kmemleak.h>
120 #include <linux/kasan.h>
121
122 struct mem_cgroup;
123 /*
124 * struct kmem_cache related prototypes
125 */
126 void __init kmem_cache_init(void);
127 bool slab_is_available(void);
128
129 struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
130 unsigned long,
131 void (*)(void *));
132 void kmem_cache_destroy(struct kmem_cache *);
133 int kmem_cache_shrink(struct kmem_cache *);
134
135 void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *);
136 void memcg_deactivate_kmem_caches(struct mem_cgroup *);
137 void memcg_destroy_kmem_caches(struct mem_cgroup *);
138
139 /*
140 * Please use this macro to create slab caches. Simply specify the
141 * name of the structure and maybe some flags that are listed above.
142 *
143 * The alignment of the struct determines object alignment. If you
144 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
145 * then the objects will be properly aligned in SMP configurations.
146 */
147 #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
148 sizeof(struct __struct), __alignof__(struct __struct),\
149 (__flags), NULL)
150
151 /*
152 * Common kmalloc functions provided by all allocators
153 */
154 void * __must_check __krealloc(const void *, size_t, gfp_t);
155 void * __must_check krealloc(const void *, size_t, gfp_t);
156 void kfree(const void *);
157 void kzfree(const void *);
158 size_t ksize(const void *);
159
160 #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
161 const char *__check_heap_object(const void *ptr, unsigned long n,
162 struct page *page);
163 #else
164 static inline const char *__check_heap_object(const void *ptr,
165 unsigned long n,
166 struct page *page)
167 {
168 return NULL;
169 }
170 #endif
171
172 /*
173 * Some archs want to perform DMA into kmalloc caches and need a guaranteed
174 * alignment larger than the alignment of a 64-bit integer.
175 * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
176 */
177 #if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
178 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
179 #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
180 #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
181 #else
182 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
183 #endif
184
185 /*
186 * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
187 * Intended for arches that get misalignment faults even for 64 bit integer
188 * aligned buffers.
189 */
190 #ifndef ARCH_SLAB_MINALIGN
191 #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
192 #endif
193
194 /*
195 * kmalloc and friends return ARCH_KMALLOC_MINALIGN aligned
196 * pointers. kmem_cache_alloc and friends return ARCH_SLAB_MINALIGN
197 * aligned pointers.
198 */
199 #define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
200 #define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
201 #define __assume_page_alignment __assume_aligned(PAGE_SIZE)
202
203 /*
204 * Kmalloc array related definitions
205 */
206
207 #ifdef CONFIG_SLAB
208 /*
209 * The largest kmalloc size supported by the SLAB allocators is
210 * 32 megabyte (2^25) or the maximum allocatable page order if that is
211 * less than 32 MB.
212 *
213 * WARNING: Its not easy to increase this value since the allocators have
214 * to do various tricks to work around compiler limitations in order to
215 * ensure proper constant folding.
216 */
217 #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
218 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
219 #define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH
220 #ifndef KMALLOC_SHIFT_LOW
221 #define KMALLOC_SHIFT_LOW 5
222 #endif
223 #endif
224
225 #ifdef CONFIG_SLUB
226 /*
227 * SLUB directly allocates requests fitting in to an order-1 page
228 * (PAGE_SIZE*2). Larger requests are passed to the page allocator.
229 */
230 #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
231 #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
232 #ifndef KMALLOC_SHIFT_LOW
233 #define KMALLOC_SHIFT_LOW 3
234 #endif
235 #endif
236
237 #ifdef CONFIG_SLOB
238 /*
239 * SLOB passes all requests larger than one page to the page allocator.
240 * No kmalloc array is necessary since objects of different sizes can
241 * be allocated from the same page.
242 */
243 #define KMALLOC_SHIFT_HIGH PAGE_SHIFT
244 #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
245 #ifndef KMALLOC_SHIFT_LOW
246 #define KMALLOC_SHIFT_LOW 3
247 #endif
248 #endif
249
250 /* Maximum allocatable size */
251 #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
252 /* Maximum size for which we actually use a slab cache */
253 #define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
254 /* Maximum order allocatable via the slab allocagtor */
255 #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
256
257 /*
258 * Kmalloc subsystem.
259 */
260 #ifndef KMALLOC_MIN_SIZE
261 #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
262 #endif
263
264 /*
265 * This restriction comes from byte sized index implementation.
266 * Page size is normally 2^12 bytes and, in this case, if we want to use
267 * byte sized index which can represent 2^8 entries, the size of the object
268 * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
269 * If minimum size of kmalloc is less than 16, we use it as minimum object
270 * size and give up to use byte sized index.
271 */
272 #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
273 (KMALLOC_MIN_SIZE) : 16)
274
275 #ifndef CONFIG_SLOB
276 extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
277 #ifdef CONFIG_ZONE_DMA
278 extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
279 #endif
280
281 /*
282 * Figure out which kmalloc slab an allocation of a certain size
283 * belongs to.
284 * 0 = zero alloc
285 * 1 = 65 .. 96 bytes
286 * 2 = 129 .. 192 bytes
287 * n = 2^(n-1)+1 .. 2^n
288 */
289 static __always_inline int kmalloc_index(size_t size)
290 {
291 if (!size)
292 return 0;
293
294 if (size <= KMALLOC_MIN_SIZE)
295 return KMALLOC_SHIFT_LOW;
296
297 if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
298 return 1;
299 if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
300 return 2;
301 if (size <= 8) return 3;
302 if (size <= 16) return 4;
303 if (size <= 32) return 5;
304 if (size <= 64) return 6;
305 if (size <= 128) return 7;
306 if (size <= 256) return 8;
307 if (size <= 512) return 9;
308 if (size <= 1024) return 10;
309 if (size <= 2 * 1024) return 11;
310 if (size <= 4 * 1024) return 12;
311 if (size <= 8 * 1024) return 13;
312 if (size <= 16 * 1024) return 14;
313 if (size <= 32 * 1024) return 15;
314 if (size <= 64 * 1024) return 16;
315 if (size <= 128 * 1024) return 17;
316 if (size <= 256 * 1024) return 18;
317 if (size <= 512 * 1024) return 19;
318 if (size <= 1024 * 1024) return 20;
319 if (size <= 2 * 1024 * 1024) return 21;
320 if (size <= 4 * 1024 * 1024) return 22;
321 if (size <= 8 * 1024 * 1024) return 23;
322 if (size <= 16 * 1024 * 1024) return 24;
323 if (size <= 32 * 1024 * 1024) return 25;
324 if (size <= 64 * 1024 * 1024) return 26;
325 BUG();
326
327 /* Will never be reached. Needed because the compiler may complain */
328 return -1;
329 }
330 #endif /* !CONFIG_SLOB */
331
332 void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc;
333 void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc;
334 void kmem_cache_free(struct kmem_cache *, void *);
335
336 /*
337 * Bulk allocation and freeing operations. These are accelerated in an
338 * allocator specific way to avoid taking locks repeatedly or building
339 * metadata structures unnecessarily.
340 *
341 * Note that interrupts must be enabled when calling these functions.
342 */
343 void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
344 int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
345
346 /*
347 * Caller must not use kfree_bulk() on memory not originally allocated
348 * by kmalloc(), because the SLOB allocator cannot handle this.
349 */
350 static __always_inline void kfree_bulk(size_t size, void **p)
351 {
352 kmem_cache_free_bulk(NULL, size, p);
353 }
354
355 #ifdef CONFIG_NUMA
356 void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc;
357 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc;
358 #else
359 static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
360 {
361 return __kmalloc(size, flags);
362 }
363
364 static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
365 {
366 return kmem_cache_alloc(s, flags);
367 }
368 #endif
369
370 #ifdef CONFIG_TRACING
371 extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc;
372
373 #ifdef CONFIG_NUMA
374 extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
375 gfp_t gfpflags,
376 int node, size_t size) __assume_slab_alignment __malloc;
377 #else
378 static __always_inline void *
379 kmem_cache_alloc_node_trace(struct kmem_cache *s,
380 gfp_t gfpflags,
381 int node, size_t size)
382 {
383 return kmem_cache_alloc_trace(s, gfpflags, size);
384 }
385 #endif /* CONFIG_NUMA */
386
387 #else /* CONFIG_TRACING */
388 static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
389 gfp_t flags, size_t size)
390 {
391 void *ret = kmem_cache_alloc(s, flags);
392
393 kasan_kmalloc(s, ret, size, flags);
394 return ret;
395 }
396
397 static __always_inline void *
398 kmem_cache_alloc_node_trace(struct kmem_cache *s,
399 gfp_t gfpflags,
400 int node, size_t size)
401 {
402 void *ret = kmem_cache_alloc_node(s, gfpflags, node);
403
404 kasan_kmalloc(s, ret, size, gfpflags);
405 return ret;
406 }
407 #endif /* CONFIG_TRACING */
408
409 extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
410
411 #ifdef CONFIG_TRACING
412 extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
413 #else
414 static __always_inline void *
415 kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
416 {
417 return kmalloc_order(size, flags, order);
418 }
419 #endif
420
421 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
422 {
423 unsigned int order = get_order(size);
424 return kmalloc_order_trace(size, flags, order);
425 }
426
427 /**
428 * kmalloc - allocate memory
429 * @size: how many bytes of memory are required.
430 * @flags: the type of memory to allocate.
431 *
432 * kmalloc is the normal method of allocating memory
433 * for objects smaller than page size in the kernel.
434 *
435 * The @flags argument may be one of:
436 *
437 * %GFP_USER - Allocate memory on behalf of user. May sleep.
438 *
439 * %GFP_KERNEL - Allocate normal kernel ram. May sleep.
440 *
441 * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools.
442 * For example, use this inside interrupt handlers.
443 *
444 * %GFP_HIGHUSER - Allocate pages from high memory.
445 *
446 * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
447 *
448 * %GFP_NOFS - Do not make any fs calls while trying to get memory.
449 *
450 * %GFP_NOWAIT - Allocation will not sleep.
451 *
452 * %__GFP_THISNODE - Allocate node-local memory only.
453 *
454 * %GFP_DMA - Allocation suitable for DMA.
455 * Should only be used for kmalloc() caches. Otherwise, use a
456 * slab created with SLAB_DMA.
457 *
458 * Also it is possible to set different flags by OR'ing
459 * in one or more of the following additional @flags:
460 *
461 * %__GFP_COLD - Request cache-cold pages instead of
462 * trying to return cache-warm pages.
463 *
464 * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
465 *
466 * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
467 * (think twice before using).
468 *
469 * %__GFP_NORETRY - If memory is not immediately available,
470 * then give up at once.
471 *
472 * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
473 *
474 * %__GFP_RETRY_MAYFAIL - Try really hard to succeed the allocation but fail
475 * eventually.
476 *
477 * There are other flags available as well, but these are not intended
478 * for general use, and so are not documented here. For a full list of
479 * potential flags, always refer to linux/gfp.h.
480 */
481 static __always_inline void *kmalloc(size_t size, gfp_t flags)
482 {
483 if (__builtin_constant_p(size)) {
484 if (size > KMALLOC_MAX_CACHE_SIZE)
485 return kmalloc_large(size, flags);
486 #ifndef CONFIG_SLOB
487 if (!(flags & GFP_DMA)) {
488 int index = kmalloc_index(size);
489
490 if (!index)
491 return ZERO_SIZE_PTR;
492
493 return kmem_cache_alloc_trace(kmalloc_caches[index],
494 flags, size);
495 }
496 #endif
497 }
498 return __kmalloc(size, flags);
499 }
500
501 /*
502 * Determine size used for the nth kmalloc cache.
503 * return size or 0 if a kmalloc cache for that
504 * size does not exist
505 */
506 static __always_inline int kmalloc_size(int n)
507 {
508 #ifndef CONFIG_SLOB
509 if (n > 2)
510 return 1 << n;
511
512 if (n == 1 && KMALLOC_MIN_SIZE <= 32)
513 return 96;
514
515 if (n == 2 && KMALLOC_MIN_SIZE <= 64)
516 return 192;
517 #endif
518 return 0;
519 }
520
521 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
522 {
523 #ifndef CONFIG_SLOB
524 if (__builtin_constant_p(size) &&
525 size <= KMALLOC_MAX_CACHE_SIZE && !(flags & GFP_DMA)) {
526 int i = kmalloc_index(size);
527
528 if (!i)
529 return ZERO_SIZE_PTR;
530
531 return kmem_cache_alloc_node_trace(kmalloc_caches[i],
532 flags, node, size);
533 }
534 #endif
535 return __kmalloc_node(size, flags, node);
536 }
537
538 struct memcg_cache_array {
539 struct rcu_head rcu;
540 struct kmem_cache *entries[0];
541 };
542
543 /*
544 * This is the main placeholder for memcg-related information in kmem caches.
545 * Both the root cache and the child caches will have it. For the root cache,
546 * this will hold a dynamically allocated array large enough to hold
547 * information about the currently limited memcgs in the system. To allow the
548 * array to be accessed without taking any locks, on relocation we free the old
549 * version only after a grace period.
550 *
551 * Root and child caches hold different metadata.
552 *
553 * @root_cache: Common to root and child caches. NULL for root, pointer to
554 * the root cache for children.
555 *
556 * The following fields are specific to root caches.
557 *
558 * @memcg_caches: kmemcg ID indexed table of child caches. This table is
559 * used to index child cachces during allocation and cleared
560 * early during shutdown.
561 *
562 * @root_caches_node: List node for slab_root_caches list.
563 *
564 * @children: List of all child caches. While the child caches are also
565 * reachable through @memcg_caches, a child cache remains on
566 * this list until it is actually destroyed.
567 *
568 * The following fields are specific to child caches.
569 *
570 * @memcg: Pointer to the memcg this cache belongs to.
571 *
572 * @children_node: List node for @root_cache->children list.
573 *
574 * @kmem_caches_node: List node for @memcg->kmem_caches list.
575 */
576 struct memcg_cache_params {
577 struct kmem_cache *root_cache;
578 union {
579 struct {
580 struct memcg_cache_array __rcu *memcg_caches;
581 struct list_head __root_caches_node;
582 struct list_head children;
583 };
584 struct {
585 struct mem_cgroup *memcg;
586 struct list_head children_node;
587 struct list_head kmem_caches_node;
588
589 void (*deact_fn)(struct kmem_cache *);
590 union {
591 struct rcu_head deact_rcu_head;
592 struct work_struct deact_work;
593 };
594 };
595 };
596 };
597
598 int memcg_update_all_caches(int num_memcgs);
599
600 /**
601 * kmalloc_array - allocate memory for an array.
602 * @n: number of elements.
603 * @size: element size.
604 * @flags: the type of memory to allocate (see kmalloc).
605 */
606 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
607 {
608 if (size != 0 && n > SIZE_MAX / size)
609 return NULL;
610 if (__builtin_constant_p(n) && __builtin_constant_p(size))
611 return kmalloc(n * size, flags);
612 return __kmalloc(n * size, flags);
613 }
614
615 /**
616 * kcalloc - allocate memory for an array. The memory is set to zero.
617 * @n: number of elements.
618 * @size: element size.
619 * @flags: the type of memory to allocate (see kmalloc).
620 */
621 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
622 {
623 return kmalloc_array(n, size, flags | __GFP_ZERO);
624 }
625
626 /*
627 * kmalloc_track_caller is a special version of kmalloc that records the
628 * calling function of the routine calling it for slab leak tracking instead
629 * of just the calling function (confusing, eh?).
630 * It's useful when the call to kmalloc comes from a widely-used standard
631 * allocator where we care about the real place the memory allocation
632 * request comes from.
633 */
634 extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
635 #define kmalloc_track_caller(size, flags) \
636 __kmalloc_track_caller(size, flags, _RET_IP_)
637
638 #ifdef CONFIG_NUMA
639 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
640 #define kmalloc_node_track_caller(size, flags, node) \
641 __kmalloc_node_track_caller(size, flags, node, \
642 _RET_IP_)
643
644 #else /* CONFIG_NUMA */
645
646 #define kmalloc_node_track_caller(size, flags, node) \
647 kmalloc_track_caller(size, flags)
648
649 #endif /* CONFIG_NUMA */
650
651 /*
652 * Shortcuts
653 */
654 static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
655 {
656 return kmem_cache_alloc(k, flags | __GFP_ZERO);
657 }
658
659 /**
660 * kzalloc - allocate memory. The memory is set to zero.
661 * @size: how many bytes of memory are required.
662 * @flags: the type of memory to allocate (see kmalloc).
663 */
664 static inline void *kzalloc(size_t size, gfp_t flags)
665 {
666 return kmalloc(size, flags | __GFP_ZERO);
667 }
668
669 /**
670 * kzalloc_node - allocate zeroed memory from a particular memory node.
671 * @size: how many bytes of memory are required.
672 * @flags: the type of memory to allocate (see kmalloc).
673 * @node: memory node from which to allocate
674 */
675 static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
676 {
677 return kmalloc_node(size, flags | __GFP_ZERO, node);
678 }
679
680 unsigned int kmem_cache_size(struct kmem_cache *s);
681 void __init kmem_cache_init_late(void);
682
683 #if defined(CONFIG_SMP) && defined(CONFIG_SLAB)
684 int slab_prepare_cpu(unsigned int cpu);
685 int slab_dead_cpu(unsigned int cpu);
686 #else
687 #define slab_prepare_cpu NULL
688 #define slab_dead_cpu NULL
689 #endif
690
691 #endif /* _LINUX_SLAB_H */