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b2441318 1/* SPDX-License-Identifier: GPL-2.0 */
1da177e4 2/*
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3 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
4 *
cde53535 5 * (C) SGI 2006, Christoph Lameter
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6 * Cleaned up and restructured to ease the addition of alternative
7 * implementations of SLAB allocators.
f1b6eb6e
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8 * (C) Linux Foundation 2008-2013
9 * Unified interface for all slab allocators
1da177e4
LT
10 */
11
12#ifndef _LINUX_SLAB_H
13#define _LINUX_SLAB_H
14
1b1cec4b 15#include <linux/gfp.h>
1b1cec4b 16#include <linux/types.h>
1f458cbf
GC
17#include <linux/workqueue.h>
18
1da177e4 19
2e892f43
CL
20/*
21 * Flags to pass to kmem_cache_create().
124dee09 22 * The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
1da177e4 23 */
becfda68 24#define SLAB_CONSISTENCY_CHECKS 0x00000100UL /* DEBUG: Perform (expensive) checks on alloc/free */
55935a34
CL
25#define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */
26#define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */
27#define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */
2e892f43 28#define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */
2e892f43 29#define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */
2e892f43 30#define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */
d7de4c1d 31/*
5f0d5a3a 32 * SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
d7de4c1d
PZ
33 *
34 * This delays freeing the SLAB page by a grace period, it does _NOT_
35 * delay object freeing. This means that if you do kmem_cache_free()
36 * that memory location is free to be reused at any time. Thus it may
37 * be possible to see another object there in the same RCU grace period.
38 *
39 * This feature only ensures the memory location backing the object
40 * stays valid, the trick to using this is relying on an independent
41 * object validation pass. Something like:
42 *
43 * rcu_read_lock()
44 * again:
45 * obj = lockless_lookup(key);
46 * if (obj) {
47 * if (!try_get_ref(obj)) // might fail for free objects
48 * goto again;
49 *
50 * if (obj->key != key) { // not the object we expected
51 * put_ref(obj);
52 * goto again;
53 * }
54 * }
55 * rcu_read_unlock();
56 *
68126702
JK
57 * This is useful if we need to approach a kernel structure obliquely,
58 * from its address obtained without the usual locking. We can lock
59 * the structure to stabilize it and check it's still at the given address,
60 * only if we can be sure that the memory has not been meanwhile reused
61 * for some other kind of object (which our subsystem's lock might corrupt).
62 *
63 * rcu_read_lock before reading the address, then rcu_read_unlock after
64 * taking the spinlock within the structure expected at that address.
5f0d5a3a
PM
65 *
66 * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
d7de4c1d 67 */
5f0d5a3a 68#define SLAB_TYPESAFE_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */
101a5001 69#define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */
81819f0f 70#define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */
1da177e4 71
30327acf
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72/* Flag to prevent checks on free */
73#ifdef CONFIG_DEBUG_OBJECTS
74# define SLAB_DEBUG_OBJECTS 0x00400000UL
75#else
76# define SLAB_DEBUG_OBJECTS 0x00000000UL
77#endif
78
d5cff635
CM
79#define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */
80
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81/* Don't track use of uninitialized memory */
82#ifdef CONFIG_KMEMCHECK
83# define SLAB_NOTRACK 0x01000000UL
84#else
85# define SLAB_NOTRACK 0x00000000UL
86#endif
4c13dd3b
DM
87#ifdef CONFIG_FAILSLAB
88# define SLAB_FAILSLAB 0x02000000UL /* Fault injection mark */
89#else
90# define SLAB_FAILSLAB 0x00000000UL
91#endif
127424c8 92#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
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VD
93# define SLAB_ACCOUNT 0x04000000UL /* Account to memcg */
94#else
95# define SLAB_ACCOUNT 0x00000000UL
96#endif
2dff4405 97
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98#ifdef CONFIG_KASAN
99#define SLAB_KASAN 0x08000000UL
100#else
101#define SLAB_KASAN 0x00000000UL
102#endif
103
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104/* The following flags affect the page allocator grouping pages by mobility */
105#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
106#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
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CL
107/*
108 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
109 *
110 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
111 *
112 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
113 * Both make kfree a no-op.
114 */
115#define ZERO_SIZE_PTR ((void *)16)
116
1d4ec7b1 117#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
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118 (unsigned long)ZERO_SIZE_PTR)
119
f1b6eb6e 120#include <linux/kmemleak.h>
0316bec2 121#include <linux/kasan.h>
3b0efdfa 122
2633d7a0 123struct mem_cgroup;
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124/*
125 * struct kmem_cache related prototypes
126 */
127void __init kmem_cache_init(void);
fda90124 128bool slab_is_available(void);
1da177e4 129
2e892f43 130struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
ebe29738 131 unsigned long,
51cc5068 132 void (*)(void *));
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133void kmem_cache_destroy(struct kmem_cache *);
134int kmem_cache_shrink(struct kmem_cache *);
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VD
135
136void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *);
137void memcg_deactivate_kmem_caches(struct mem_cgroup *);
138void memcg_destroy_kmem_caches(struct mem_cgroup *);
2e892f43 139
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CL
140/*
141 * Please use this macro to create slab caches. Simply specify the
142 * name of the structure and maybe some flags that are listed above.
143 *
144 * The alignment of the struct determines object alignment. If you
145 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
146 * then the objects will be properly aligned in SMP configurations.
147 */
148#define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
149 sizeof(struct __struct), __alignof__(struct __struct),\
20c2df83 150 (__flags), NULL)
0a31bd5f 151
34504667
CL
152/*
153 * Common kmalloc functions provided by all allocators
154 */
155void * __must_check __krealloc(const void *, size_t, gfp_t);
156void * __must_check krealloc(const void *, size_t, gfp_t);
157void kfree(const void *);
158void kzfree(const void *);
159size_t ksize(const void *);
160
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KC
161#ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
162const char *__check_heap_object(const void *ptr, unsigned long n,
163 struct page *page);
164#else
165static inline const char *__check_heap_object(const void *ptr,
166 unsigned long n,
167 struct page *page)
168{
169 return NULL;
170}
171#endif
172
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CL
173/*
174 * Some archs want to perform DMA into kmalloc caches and need a guaranteed
175 * alignment larger than the alignment of a 64-bit integer.
176 * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
177 */
178#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
179#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
180#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
181#define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
182#else
183#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
184#endif
185
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RV
186/*
187 * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
188 * Intended for arches that get misalignment faults even for 64 bit integer
189 * aligned buffers.
190 */
191#ifndef ARCH_SLAB_MINALIGN
192#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
193#endif
194
195/*
196 * kmalloc and friends return ARCH_KMALLOC_MINALIGN aligned
197 * pointers. kmem_cache_alloc and friends return ARCH_SLAB_MINALIGN
198 * aligned pointers.
199 */
200#define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
201#define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
202#define __assume_page_alignment __assume_aligned(PAGE_SIZE)
203
0aa817f0 204/*
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205 * Kmalloc array related definitions
206 */
207
208#ifdef CONFIG_SLAB
209/*
210 * The largest kmalloc size supported by the SLAB allocators is
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211 * 32 megabyte (2^25) or the maximum allocatable page order if that is
212 * less than 32 MB.
213 *
214 * WARNING: Its not easy to increase this value since the allocators have
215 * to do various tricks to work around compiler limitations in order to
216 * ensure proper constant folding.
217 */
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218#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
219 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
95a05b42 220#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH
c601fd69 221#ifndef KMALLOC_SHIFT_LOW
95a05b42 222#define KMALLOC_SHIFT_LOW 5
c601fd69 223#endif
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224#endif
225
226#ifdef CONFIG_SLUB
95a05b42 227/*
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228 * SLUB directly allocates requests fitting in to an order-1 page
229 * (PAGE_SIZE*2). Larger requests are passed to the page allocator.
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230 */
231#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
bb1107f7 232#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
c601fd69 233#ifndef KMALLOC_SHIFT_LOW
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234#define KMALLOC_SHIFT_LOW 3
235#endif
c601fd69 236#endif
0aa817f0 237
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238#ifdef CONFIG_SLOB
239/*
433a91ff 240 * SLOB passes all requests larger than one page to the page allocator.
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241 * No kmalloc array is necessary since objects of different sizes can
242 * be allocated from the same page.
243 */
069e2b35 244#define KMALLOC_SHIFT_HIGH PAGE_SHIFT
bb1107f7 245#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1)
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246#ifndef KMALLOC_SHIFT_LOW
247#define KMALLOC_SHIFT_LOW 3
248#endif
249#endif
250
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251/* Maximum allocatable size */
252#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
253/* Maximum size for which we actually use a slab cache */
254#define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
255/* Maximum order allocatable via the slab allocagtor */
256#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
0aa817f0 257
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258/*
259 * Kmalloc subsystem.
260 */
c601fd69 261#ifndef KMALLOC_MIN_SIZE
95a05b42 262#define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
ce6a5026
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263#endif
264
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265/*
266 * This restriction comes from byte sized index implementation.
267 * Page size is normally 2^12 bytes and, in this case, if we want to use
268 * byte sized index which can represent 2^8 entries, the size of the object
269 * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
270 * If minimum size of kmalloc is less than 16, we use it as minimum object
271 * size and give up to use byte sized index.
272 */
273#define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
274 (KMALLOC_MIN_SIZE) : 16)
275
069e2b35 276#ifndef CONFIG_SLOB
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277extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
278#ifdef CONFIG_ZONE_DMA
279extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
280#endif
281
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282/*
283 * Figure out which kmalloc slab an allocation of a certain size
284 * belongs to.
285 * 0 = zero alloc
286 * 1 = 65 .. 96 bytes
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287 * 2 = 129 .. 192 bytes
288 * n = 2^(n-1)+1 .. 2^n
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289 */
290static __always_inline int kmalloc_index(size_t size)
291{
292 if (!size)
293 return 0;
294
295 if (size <= KMALLOC_MIN_SIZE)
296 return KMALLOC_SHIFT_LOW;
297
298 if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
299 return 1;
300 if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
301 return 2;
302 if (size <= 8) return 3;
303 if (size <= 16) return 4;
304 if (size <= 32) return 5;
305 if (size <= 64) return 6;
306 if (size <= 128) return 7;
307 if (size <= 256) return 8;
308 if (size <= 512) return 9;
309 if (size <= 1024) return 10;
310 if (size <= 2 * 1024) return 11;
311 if (size <= 4 * 1024) return 12;
312 if (size <= 8 * 1024) return 13;
313 if (size <= 16 * 1024) return 14;
314 if (size <= 32 * 1024) return 15;
315 if (size <= 64 * 1024) return 16;
316 if (size <= 128 * 1024) return 17;
317 if (size <= 256 * 1024) return 18;
318 if (size <= 512 * 1024) return 19;
319 if (size <= 1024 * 1024) return 20;
320 if (size <= 2 * 1024 * 1024) return 21;
321 if (size <= 4 * 1024 * 1024) return 22;
322 if (size <= 8 * 1024 * 1024) return 23;
323 if (size <= 16 * 1024 * 1024) return 24;
324 if (size <= 32 * 1024 * 1024) return 25;
325 if (size <= 64 * 1024 * 1024) return 26;
326 BUG();
327
328 /* Will never be reached. Needed because the compiler may complain */
329 return -1;
330}
069e2b35 331#endif /* !CONFIG_SLOB */
ce6a5026 332
48a27055
RV
333void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc;
334void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc;
2a4db7eb 335void kmem_cache_free(struct kmem_cache *, void *);
f1b6eb6e 336
484748f0 337/*
9f706d68 338 * Bulk allocation and freeing operations. These are accelerated in an
484748f0
CL
339 * allocator specific way to avoid taking locks repeatedly or building
340 * metadata structures unnecessarily.
341 *
342 * Note that interrupts must be enabled when calling these functions.
343 */
344void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
865762a8 345int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
484748f0 346
ca257195
JDB
347/*
348 * Caller must not use kfree_bulk() on memory not originally allocated
349 * by kmalloc(), because the SLOB allocator cannot handle this.
350 */
351static __always_inline void kfree_bulk(size_t size, void **p)
352{
353 kmem_cache_free_bulk(NULL, size, p);
354}
355
f1b6eb6e 356#ifdef CONFIG_NUMA
48a27055
RV
357void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc;
358void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc;
f1b6eb6e
CL
359#else
360static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
361{
362 return __kmalloc(size, flags);
363}
364
365static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
366{
367 return kmem_cache_alloc(s, flags);
368}
369#endif
370
371#ifdef CONFIG_TRACING
48a27055 372extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc;
f1b6eb6e
CL
373
374#ifdef CONFIG_NUMA
375extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
376 gfp_t gfpflags,
48a27055 377 int node, size_t size) __assume_slab_alignment __malloc;
f1b6eb6e
CL
378#else
379static __always_inline void *
380kmem_cache_alloc_node_trace(struct kmem_cache *s,
381 gfp_t gfpflags,
382 int node, size_t size)
383{
384 return kmem_cache_alloc_trace(s, gfpflags, size);
385}
386#endif /* CONFIG_NUMA */
387
388#else /* CONFIG_TRACING */
389static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
390 gfp_t flags, size_t size)
391{
0316bec2
AR
392 void *ret = kmem_cache_alloc(s, flags);
393
505f5dcb 394 kasan_kmalloc(s, ret, size, flags);
0316bec2 395 return ret;
f1b6eb6e
CL
396}
397
398static __always_inline void *
399kmem_cache_alloc_node_trace(struct kmem_cache *s,
400 gfp_t gfpflags,
401 int node, size_t size)
402{
0316bec2
AR
403 void *ret = kmem_cache_alloc_node(s, gfpflags, node);
404
505f5dcb 405 kasan_kmalloc(s, ret, size, gfpflags);
0316bec2 406 return ret;
f1b6eb6e
CL
407}
408#endif /* CONFIG_TRACING */
409
48a27055 410extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
f1b6eb6e
CL
411
412#ifdef CONFIG_TRACING
48a27055 413extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
f1b6eb6e
CL
414#else
415static __always_inline void *
416kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
417{
418 return kmalloc_order(size, flags, order);
419}
ce6a5026
CL
420#endif
421
f1b6eb6e
CL
422static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
423{
424 unsigned int order = get_order(size);
425 return kmalloc_order_trace(size, flags, order);
426}
427
428/**
429 * kmalloc - allocate memory
430 * @size: how many bytes of memory are required.
7e3528c3 431 * @flags: the type of memory to allocate.
f1b6eb6e
CL
432 *
433 * kmalloc is the normal method of allocating memory
434 * for objects smaller than page size in the kernel.
7e3528c3
RD
435 *
436 * The @flags argument may be one of:
437 *
438 * %GFP_USER - Allocate memory on behalf of user. May sleep.
439 *
440 * %GFP_KERNEL - Allocate normal kernel ram. May sleep.
441 *
442 * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools.
443 * For example, use this inside interrupt handlers.
444 *
445 * %GFP_HIGHUSER - Allocate pages from high memory.
446 *
447 * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
448 *
449 * %GFP_NOFS - Do not make any fs calls while trying to get memory.
450 *
451 * %GFP_NOWAIT - Allocation will not sleep.
452 *
e97ca8e5 453 * %__GFP_THISNODE - Allocate node-local memory only.
7e3528c3
RD
454 *
455 * %GFP_DMA - Allocation suitable for DMA.
456 * Should only be used for kmalloc() caches. Otherwise, use a
457 * slab created with SLAB_DMA.
458 *
459 * Also it is possible to set different flags by OR'ing
460 * in one or more of the following additional @flags:
461 *
462 * %__GFP_COLD - Request cache-cold pages instead of
463 * trying to return cache-warm pages.
464 *
465 * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
466 *
467 * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
468 * (think twice before using).
469 *
470 * %__GFP_NORETRY - If memory is not immediately available,
471 * then give up at once.
472 *
473 * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
474 *
dcda9b04
MH
475 * %__GFP_RETRY_MAYFAIL - Try really hard to succeed the allocation but fail
476 * eventually.
7e3528c3
RD
477 *
478 * There are other flags available as well, but these are not intended
479 * for general use, and so are not documented here. For a full list of
480 * potential flags, always refer to linux/gfp.h.
f1b6eb6e
CL
481 */
482static __always_inline void *kmalloc(size_t size, gfp_t flags)
483{
484 if (__builtin_constant_p(size)) {
485 if (size > KMALLOC_MAX_CACHE_SIZE)
486 return kmalloc_large(size, flags);
487#ifndef CONFIG_SLOB
488 if (!(flags & GFP_DMA)) {
489 int index = kmalloc_index(size);
490
491 if (!index)
492 return ZERO_SIZE_PTR;
493
494 return kmem_cache_alloc_trace(kmalloc_caches[index],
495 flags, size);
496 }
497#endif
498 }
499 return __kmalloc(size, flags);
500}
501
ce6a5026
CL
502/*
503 * Determine size used for the nth kmalloc cache.
504 * return size or 0 if a kmalloc cache for that
505 * size does not exist
506 */
507static __always_inline int kmalloc_size(int n)
508{
069e2b35 509#ifndef CONFIG_SLOB
ce6a5026
CL
510 if (n > 2)
511 return 1 << n;
512
513 if (n == 1 && KMALLOC_MIN_SIZE <= 32)
514 return 96;
515
516 if (n == 2 && KMALLOC_MIN_SIZE <= 64)
517 return 192;
069e2b35 518#endif
ce6a5026
CL
519 return 0;
520}
ce6a5026 521
f1b6eb6e
CL
522static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
523{
524#ifndef CONFIG_SLOB
525 if (__builtin_constant_p(size) &&
23774a2f 526 size <= KMALLOC_MAX_CACHE_SIZE && !(flags & GFP_DMA)) {
f1b6eb6e
CL
527 int i = kmalloc_index(size);
528
529 if (!i)
530 return ZERO_SIZE_PTR;
531
532 return kmem_cache_alloc_node_trace(kmalloc_caches[i],
533 flags, node, size);
534 }
535#endif
536 return __kmalloc_node(size, flags, node);
537}
538
f7ce3190
VD
539struct memcg_cache_array {
540 struct rcu_head rcu;
541 struct kmem_cache *entries[0];
542};
543
ba6c496e
GC
544/*
545 * This is the main placeholder for memcg-related information in kmem caches.
ba6c496e
GC
546 * Both the root cache and the child caches will have it. For the root cache,
547 * this will hold a dynamically allocated array large enough to hold
f8570263
VD
548 * information about the currently limited memcgs in the system. To allow the
549 * array to be accessed without taking any locks, on relocation we free the old
550 * version only after a grace period.
ba6c496e 551 *
9eeadc8b 552 * Root and child caches hold different metadata.
ba6c496e 553 *
9eeadc8b
TH
554 * @root_cache: Common to root and child caches. NULL for root, pointer to
555 * the root cache for children.
426589f5 556 *
9eeadc8b
TH
557 * The following fields are specific to root caches.
558 *
559 * @memcg_caches: kmemcg ID indexed table of child caches. This table is
560 * used to index child cachces during allocation and cleared
561 * early during shutdown.
562 *
510ded33
TH
563 * @root_caches_node: List node for slab_root_caches list.
564 *
9eeadc8b
TH
565 * @children: List of all child caches. While the child caches are also
566 * reachable through @memcg_caches, a child cache remains on
567 * this list until it is actually destroyed.
568 *
569 * The following fields are specific to child caches.
570 *
571 * @memcg: Pointer to the memcg this cache belongs to.
572 *
573 * @children_node: List node for @root_cache->children list.
bc2791f8
TH
574 *
575 * @kmem_caches_node: List node for @memcg->kmem_caches list.
ba6c496e
GC
576 */
577struct memcg_cache_params {
9eeadc8b 578 struct kmem_cache *root_cache;
ba6c496e 579 union {
9eeadc8b
TH
580 struct {
581 struct memcg_cache_array __rcu *memcg_caches;
510ded33 582 struct list_head __root_caches_node;
9eeadc8b
TH
583 struct list_head children;
584 };
2633d7a0
GC
585 struct {
586 struct mem_cgroup *memcg;
9eeadc8b 587 struct list_head children_node;
bc2791f8 588 struct list_head kmem_caches_node;
01fb58bc
TH
589
590 void (*deact_fn)(struct kmem_cache *);
591 union {
592 struct rcu_head deact_rcu_head;
593 struct work_struct deact_work;
594 };
2633d7a0 595 };
ba6c496e
GC
596 };
597};
598
2633d7a0
GC
599int memcg_update_all_caches(int num_memcgs);
600
e7efa615
MO
601/**
602 * kmalloc_array - allocate memory for an array.
603 * @n: number of elements.
604 * @size: element size.
605 * @flags: the type of memory to allocate (see kmalloc).
800590f5 606 */
a8203725 607static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
1da177e4 608{
a3860c1c 609 if (size != 0 && n > SIZE_MAX / size)
6193a2ff 610 return NULL;
91c6a05f
AD
611 if (__builtin_constant_p(n) && __builtin_constant_p(size))
612 return kmalloc(n * size, flags);
a8203725
XW
613 return __kmalloc(n * size, flags);
614}
615
616/**
617 * kcalloc - allocate memory for an array. The memory is set to zero.
618 * @n: number of elements.
619 * @size: element size.
620 * @flags: the type of memory to allocate (see kmalloc).
621 */
622static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
623{
624 return kmalloc_array(n, size, flags | __GFP_ZERO);
1da177e4
LT
625}
626
1d2c8eea
CH
627/*
628 * kmalloc_track_caller is a special version of kmalloc that records the
629 * calling function of the routine calling it for slab leak tracking instead
630 * of just the calling function (confusing, eh?).
631 * It's useful when the call to kmalloc comes from a widely-used standard
632 * allocator where we care about the real place the memory allocation
633 * request comes from.
634 */
ce71e27c 635extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
1d2c8eea 636#define kmalloc_track_caller(size, flags) \
ce71e27c 637 __kmalloc_track_caller(size, flags, _RET_IP_)
1da177e4 638
97e2bde4 639#ifdef CONFIG_NUMA
ce71e27c 640extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
8b98c169
CH
641#define kmalloc_node_track_caller(size, flags, node) \
642 __kmalloc_node_track_caller(size, flags, node, \
ce71e27c 643 _RET_IP_)
2e892f43 644
8b98c169 645#else /* CONFIG_NUMA */
8b98c169
CH
646
647#define kmalloc_node_track_caller(size, flags, node) \
648 kmalloc_track_caller(size, flags)
97e2bde4 649
dfcd3610 650#endif /* CONFIG_NUMA */
10cef602 651
81cda662
CL
652/*
653 * Shortcuts
654 */
655static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
656{
657 return kmem_cache_alloc(k, flags | __GFP_ZERO);
658}
659
660/**
661 * kzalloc - allocate memory. The memory is set to zero.
662 * @size: how many bytes of memory are required.
663 * @flags: the type of memory to allocate (see kmalloc).
664 */
665static inline void *kzalloc(size_t size, gfp_t flags)
666{
667 return kmalloc(size, flags | __GFP_ZERO);
668}
669
979b0fea
JL
670/**
671 * kzalloc_node - allocate zeroed memory from a particular memory node.
672 * @size: how many bytes of memory are required.
673 * @flags: the type of memory to allocate (see kmalloc).
674 * @node: memory node from which to allocate
675 */
676static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
677{
678 return kmalloc_node(size, flags | __GFP_ZERO, node);
679}
680
07f361b2 681unsigned int kmem_cache_size(struct kmem_cache *s);
7e85ee0c
PE
682void __init kmem_cache_init_late(void);
683
6731d4f1
SAS
684#if defined(CONFIG_SMP) && defined(CONFIG_SLAB)
685int slab_prepare_cpu(unsigned int cpu);
686int slab_dead_cpu(unsigned int cpu);
687#else
688#define slab_prepare_cpu NULL
689#define slab_dead_cpu NULL
690#endif
691
1da177e4 692#endif /* _LINUX_SLAB_H */