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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 | 2 | /* |
2e892f43 CL |
3 | * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk). |
4 | * | |
cde53535 | 5 | * (C) SGI 2006, Christoph Lameter |
2e892f43 CL |
6 | * Cleaned up and restructured to ease the addition of alternative |
7 | * implementations of SLAB allocators. | |
f1b6eb6e CL |
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 TG |
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 | ||
2dff4405 VN |
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) |
230e9fc2 VD |
93 | # define SLAB_ACCOUNT 0x04000000UL /* Account to memcg */ |
94 | #else | |
95 | # define SLAB_ACCOUNT 0x00000000UL | |
96 | #endif | |
2dff4405 | 97 | |
7ed2f9e6 AP |
98 | #ifdef CONFIG_KASAN |
99 | #define SLAB_KASAN 0x08000000UL | |
100 | #else | |
101 | #define SLAB_KASAN 0x00000000UL | |
102 | #endif | |
103 | ||
e12ba74d MG |
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 */ | |
6cb8f913 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) <= \ |
6cb8f913 CL |
118 | (unsigned long)ZERO_SIZE_PTR) |
119 | ||
f1b6eb6e | 120 | #include <linux/kmemleak.h> |
0316bec2 | 121 | #include <linux/kasan.h> |
3b0efdfa | 122 | |
2633d7a0 | 123 | struct mem_cgroup; |
2e892f43 CL |
124 | /* |
125 | * struct kmem_cache related prototypes | |
126 | */ | |
127 | void __init kmem_cache_init(void); | |
fda90124 | 128 | bool slab_is_available(void); |
1da177e4 | 129 | |
2e892f43 | 130 | struct kmem_cache *kmem_cache_create(const char *, size_t, size_t, |
ebe29738 | 131 | unsigned long, |
51cc5068 | 132 | void (*)(void *)); |
2e892f43 CL |
133 | void kmem_cache_destroy(struct kmem_cache *); |
134 | int kmem_cache_shrink(struct kmem_cache *); | |
2a4db7eb VD |
135 | |
136 | void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *); | |
137 | void memcg_deactivate_kmem_caches(struct mem_cgroup *); | |
138 | void memcg_destroy_kmem_caches(struct mem_cgroup *); | |
2e892f43 | 139 | |
0a31bd5f 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 | */ | |
155 | void * __must_check __krealloc(const void *, size_t, gfp_t); | |
156 | void * __must_check krealloc(const void *, size_t, gfp_t); | |
157 | void kfree(const void *); | |
158 | void kzfree(const void *); | |
159 | size_t ksize(const void *); | |
160 | ||
f5509cc1 KC |
161 | #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR |
162 | const char *__check_heap_object(const void *ptr, unsigned long n, | |
163 | struct page *page); | |
164 | #else | |
165 | static 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 | ||
c601fd69 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 | ||
94a58c36 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 | /* |
95a05b42 CL |
205 | * Kmalloc array related definitions |
206 | */ | |
207 | ||
208 | #ifdef CONFIG_SLAB | |
209 | /* | |
210 | * The largest kmalloc size supported by the SLAB allocators is | |
0aa817f0 CL |
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 | */ | |
debee076 CL |
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 |
069e2b35 CL |
224 | #endif |
225 | ||
226 | #ifdef CONFIG_SLUB | |
95a05b42 | 227 | /* |
433a91ff DH |
228 | * SLUB directly allocates requests fitting in to an order-1 page |
229 | * (PAGE_SIZE*2). Larger requests are passed to the page allocator. | |
95a05b42 CL |
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 |
95a05b42 CL |
234 | #define KMALLOC_SHIFT_LOW 3 |
235 | #endif | |
c601fd69 | 236 | #endif |
0aa817f0 | 237 | |
069e2b35 CL |
238 | #ifdef CONFIG_SLOB |
239 | /* | |
433a91ff | 240 | * SLOB passes all requests larger than one page to the page allocator. |
069e2b35 CL |
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) |
069e2b35 CL |
246 | #ifndef KMALLOC_SHIFT_LOW |
247 | #define KMALLOC_SHIFT_LOW 3 | |
248 | #endif | |
249 | #endif | |
250 | ||
95a05b42 CL |
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 | |
ce6a5026 CL |
258 | /* |
259 | * Kmalloc subsystem. | |
260 | */ | |
c601fd69 | 261 | #ifndef KMALLOC_MIN_SIZE |
95a05b42 | 262 | #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW) |
ce6a5026 CL |
263 | #endif |
264 | ||
24f870d8 JK |
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 |
9425c58e CL |
277 | extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1]; |
278 | #ifdef CONFIG_ZONE_DMA | |
279 | extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1]; | |
280 | #endif | |
281 | ||
ce6a5026 CL |
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 | |
1ed58b60 RV |
287 | * 2 = 129 .. 192 bytes |
288 | * n = 2^(n-1)+1 .. 2^n | |
ce6a5026 CL |
289 | */ |
290 | static __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 |
333 | void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc; |
334 | void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc; | |
2a4db7eb | 335 | void 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 | */ | |
344 | void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **); | |
865762a8 | 345 | int 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 | */ | |
351 | static __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 |
357 | void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc; |
358 | void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc; | |
f1b6eb6e CL |
359 | #else |
360 | static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node) | |
361 | { | |
362 | return __kmalloc(size, flags); | |
363 | } | |
364 | ||
365 | static __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 | 372 | extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc; |
f1b6eb6e CL |
373 | |
374 | #ifdef CONFIG_NUMA | |
375 | extern 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 |
379 | static __always_inline void * | |
380 | kmem_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 */ | |
389 | static __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 | ||
398 | static __always_inline void * | |
399 | kmem_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 | 410 | extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc; |
f1b6eb6e CL |
411 | |
412 | #ifdef CONFIG_TRACING | |
48a27055 | 413 | extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc; |
f1b6eb6e CL |
414 | #else |
415 | static __always_inline void * | |
416 | kmalloc_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 |
422 | static __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 | */ |
482 | static __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 | */ | |
507 | static __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 |
522 | static __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 |
539 | struct 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 | */ |
577 | struct 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 |
599 | int 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 | 607 | static 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 | */ | |
622 | static 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 | 635 | extern 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 | 640 | extern 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 | */ | |
655 | static 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 | */ | |
665 | static 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 | */ | |
676 | static 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 | 681 | unsigned int kmem_cache_size(struct kmem_cache *s); |
7e85ee0c PE |
682 | void __init kmem_cache_init_late(void); |
683 | ||
6731d4f1 SAS |
684 | #if defined(CONFIG_SMP) && defined(CONFIG_SLAB) |
685 | int slab_prepare_cpu(unsigned int cpu); | |
686 | int 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 */ |