1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk). |
4 | * |
5 | * (C) SGI 2006, Christoph Lameter |
6 | * Cleaned up and restructured to ease the addition of alternative |
7 | * implementations of SLAB allocators. |
8 | * (C) Linux Foundation 2008-2013 |
9 | * Unified interface for all slab allocators |
10 | */ |
11 | |
12 | #ifndef _LINUX_SLAB_H |
13 | #define _LINUX_SLAB_H |
14 | |
15 | #include <linux/gfp.h> |
16 | #include <linux/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 | /* |
116 | * Ignore user specified debugging flags. |
117 | * Intended for caches created for self-tests so they have only flags |
118 | * specified in the code and other flags are ignored. |
119 | */ |
120 | #define SLAB_NO_USER_FLAGS ((slab_flags_t __force)0x10000000U) |
121 | |
122 | /* The following flags affect the page allocator grouping pages by mobility */ |
123 | /* Objects are reclaimable */ |
124 | #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) |
125 | #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ |
126 | |
127 | /* |
128 | * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. |
129 | * |
130 | * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault. |
131 | * |
132 | * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can. |
133 | * Both make kfree a no-op. |
134 | */ |
135 | #define ZERO_SIZE_PTR ((void *)16) |
136 | |
137 | #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \ |
138 | (unsigned long)ZERO_SIZE_PTR) |
139 | |
140 | #include <linux/kasan.h> |
141 | |
142 | struct list_lru; |
143 | struct mem_cgroup; |
144 | /* |
145 | * struct kmem_cache related prototypes |
146 | */ |
147 | void __init kmem_cache_init(void); |
148 | bool slab_is_available(void); |
149 | |
150 | struct kmem_cache *kmem_cache_create(const char *name, unsigned int size, |
151 | unsigned int align, slab_flags_t flags, |
152 | void (*ctor)(void *)); |
153 | struct kmem_cache *kmem_cache_create_usercopy(const char *name, |
154 | unsigned int size, unsigned int align, |
155 | slab_flags_t flags, |
156 | unsigned int useroffset, unsigned int usersize, |
157 | void (*ctor)(void *)); |
158 | void kmem_cache_destroy(struct kmem_cache *s); |
159 | int kmem_cache_shrink(struct kmem_cache *s); |
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 | */ |
187 | void * __must_check krealloc(const void *objp, size_t new_size, gfp_t flags) __alloc_size(2); |
188 | void kfree(const void *objp); |
189 | void kfree_sensitive(const void *objp); |
190 | size_t __ksize(const void *objp); |
191 | size_t ksize(const void *objp); |
192 | #ifdef CONFIG_PRINTK |
193 | bool kmem_valid_obj(void *object); |
194 | void kmem_dump_obj(void *object); |
195 | #endif |
196 | |
197 | /* |
198 | * Some archs want to perform DMA into kmalloc caches and need a guaranteed |
199 | * alignment larger than the alignment of a 64-bit integer. |
200 | * Setting ARCH_DMA_MINALIGN in arch headers allows that. |
201 | */ |
202 | #if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8 |
203 | #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN |
204 | #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN |
205 | #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN) |
206 | #else |
207 | #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) |
208 | #endif |
209 | |
210 | /* |
211 | * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment. |
212 | * Intended for arches that get misalignment faults even for 64 bit integer |
213 | * aligned buffers. |
214 | */ |
215 | #ifndef ARCH_SLAB_MINALIGN |
216 | #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long) |
217 | #endif |
218 | |
219 | /* |
220 | * Arches can define this function if they want to decide the minimum slab |
221 | * alignment at runtime. The value returned by the function must be a power |
222 | * of two and >= ARCH_SLAB_MINALIGN. |
223 | */ |
224 | #ifndef arch_slab_minalign |
225 | static inline unsigned int arch_slab_minalign(void) |
226 | { |
227 | return ARCH_SLAB_MINALIGN; |
228 | } |
229 | #endif |
230 | |
231 | /* |
232 | * kmem_cache_alloc and friends return pointers aligned to ARCH_SLAB_MINALIGN. |
233 | * kmalloc and friends return pointers aligned to both ARCH_KMALLOC_MINALIGN |
234 | * and ARCH_SLAB_MINALIGN, but here we only assume the former alignment. |
235 | */ |
236 | #define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN) |
237 | #define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN) |
238 | #define __assume_page_alignment __assume_aligned(PAGE_SIZE) |
239 | |
240 | /* |
241 | * Kmalloc array related definitions |
242 | */ |
243 | |
244 | #ifdef CONFIG_SLAB |
245 | /* |
246 | * The largest kmalloc size supported by the SLAB allocators is |
247 | * 32 megabyte (2^25) or the maximum allocatable page order if that is |
248 | * less than 32 MB. |
249 | * |
250 | * WARNING: Its not easy to increase this value since the allocators have |
251 | * to do various tricks to work around compiler limitations in order to |
252 | * ensure proper constant folding. |
253 | */ |
254 | #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ |
255 | (MAX_ORDER + PAGE_SHIFT - 1) : 25) |
256 | #define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH |
257 | #ifndef KMALLOC_SHIFT_LOW |
258 | #define KMALLOC_SHIFT_LOW 5 |
259 | #endif |
260 | #endif |
261 | |
262 | #ifdef CONFIG_SLUB |
263 | /* |
264 | * SLUB directly allocates requests fitting in to an order-1 page |
265 | * (PAGE_SIZE*2). Larger requests are passed to the page allocator. |
266 | */ |
267 | #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) |
268 | #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) |
269 | #ifndef KMALLOC_SHIFT_LOW |
270 | #define KMALLOC_SHIFT_LOW 3 |
271 | #endif |
272 | #endif |
273 | |
274 | #ifdef CONFIG_SLOB |
275 | /* |
276 | * SLOB passes all requests larger than one page to the page allocator. |
277 | * No kmalloc array is necessary since objects of different sizes can |
278 | * be allocated from the same page. |
279 | */ |
280 | #define KMALLOC_SHIFT_HIGH PAGE_SHIFT |
281 | #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) |
282 | #ifndef KMALLOC_SHIFT_LOW |
283 | #define KMALLOC_SHIFT_LOW 3 |
284 | #endif |
285 | #endif |
286 | |
287 | /* Maximum allocatable size */ |
288 | #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) |
289 | /* Maximum size for which we actually use a slab cache */ |
290 | #define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH) |
291 | /* Maximum order allocatable via the slab allocator */ |
292 | #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT) |
293 | |
294 | /* |
295 | * Kmalloc subsystem. |
296 | */ |
297 | #ifndef KMALLOC_MIN_SIZE |
298 | #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW) |
299 | #endif |
300 | |
301 | /* |
302 | * This restriction comes from byte sized index implementation. |
303 | * Page size is normally 2^12 bytes and, in this case, if we want to use |
304 | * byte sized index which can represent 2^8 entries, the size of the object |
305 | * should be equal or greater to 2^12 / 2^8 = 2^4 = 16. |
306 | * If minimum size of kmalloc is less than 16, we use it as minimum object |
307 | * size and give up to use byte sized index. |
308 | */ |
309 | #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \ |
310 | (KMALLOC_MIN_SIZE) : 16) |
311 | |
312 | /* |
313 | * Whenever changing this, take care of that kmalloc_type() and |
314 | * create_kmalloc_caches() still work as intended. |
315 | * |
316 | * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP |
317 | * is for accounted but unreclaimable and non-dma objects. All the other |
318 | * kmem caches can have both accounted and unaccounted objects. |
319 | */ |
320 | enum kmalloc_cache_type { |
321 | KMALLOC_NORMAL = 0, |
322 | #ifndef CONFIG_ZONE_DMA |
323 | KMALLOC_DMA = KMALLOC_NORMAL, |
324 | #endif |
325 | #ifndef CONFIG_MEMCG_KMEM |
326 | KMALLOC_CGROUP = KMALLOC_NORMAL, |
327 | #else |
328 | KMALLOC_CGROUP, |
329 | #endif |
330 | KMALLOC_RECLAIM, |
331 | #ifdef CONFIG_ZONE_DMA |
332 | KMALLOC_DMA, |
333 | #endif |
334 | NR_KMALLOC_TYPES |
335 | }; |
336 | |
337 | #ifndef CONFIG_SLOB |
338 | extern struct kmem_cache * |
339 | kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; |
340 | |
341 | /* |
342 | * Define gfp bits that should not be set for KMALLOC_NORMAL. |
343 | */ |
344 | #define KMALLOC_NOT_NORMAL_BITS \ |
345 | (__GFP_RECLAIMABLE | \ |
346 | (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ |
347 | (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) |
348 | |
349 | static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) |
350 | { |
351 | /* |
352 | * The most common case is KMALLOC_NORMAL, so test for it |
353 | * with a single branch for all the relevant flags. |
354 | */ |
355 | if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) |
356 | return KMALLOC_NORMAL; |
357 | |
358 | /* |
359 | * At least one of the flags has to be set. Their priorities in |
360 | * decreasing order are: |
361 | * 1) __GFP_DMA |
362 | * 2) __GFP_RECLAIMABLE |
363 | * 3) __GFP_ACCOUNT |
364 | */ |
365 | if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) |
366 | return KMALLOC_DMA; |
367 | if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) |
368 | return KMALLOC_RECLAIM; |
369 | else |
370 | return KMALLOC_CGROUP; |
371 | } |
372 | |
373 | /* |
374 | * Figure out which kmalloc slab an allocation of a certain size |
375 | * belongs to. |
376 | * 0 = zero alloc |
377 | * 1 = 65 .. 96 bytes |
378 | * 2 = 129 .. 192 bytes |
379 | * n = 2^(n-1)+1 .. 2^n |
380 | * |
381 | * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; |
382 | * typical usage is via kmalloc_index() and therefore evaluated at compile-time. |
383 | * Callers where !size_is_constant should only be test modules, where runtime |
384 | * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). |
385 | */ |
386 | static __always_inline unsigned int __kmalloc_index(size_t size, |
387 | bool size_is_constant) |
388 | { |
389 | if (!size) |
390 | return 0; |
391 | |
392 | if (size <= KMALLOC_MIN_SIZE) |
393 | return KMALLOC_SHIFT_LOW; |
394 | |
395 | if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96) |
396 | return 1; |
397 | if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192) |
398 | return 2; |
399 | if (size <= 8) return 3; |
400 | if (size <= 16) return 4; |
401 | if (size <= 32) return 5; |
402 | if (size <= 64) return 6; |
403 | if (size <= 128) return 7; |
404 | if (size <= 256) return 8; |
405 | if (size <= 512) return 9; |
406 | if (size <= 1024) return 10; |
407 | if (size <= 2 * 1024) return 11; |
408 | if (size <= 4 * 1024) return 12; |
409 | if (size <= 8 * 1024) return 13; |
410 | if (size <= 16 * 1024) return 14; |
411 | if (size <= 32 * 1024) return 15; |
412 | if (size <= 64 * 1024) return 16; |
413 | if (size <= 128 * 1024) return 17; |
414 | if (size <= 256 * 1024) return 18; |
415 | if (size <= 512 * 1024) return 19; |
416 | if (size <= 1024 * 1024) return 20; |
417 | if (size <= 2 * 1024 * 1024) return 21; |
418 | if (size <= 4 * 1024 * 1024) return 22; |
419 | if (size <= 8 * 1024 * 1024) return 23; |
420 | if (size <= 16 * 1024 * 1024) return 24; |
421 | if (size <= 32 * 1024 * 1024) return 25; |
422 | |
423 | if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) |
424 | BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()" ); |
425 | else |
426 | BUG(); |
427 | |
428 | /* Will never be reached. Needed because the compiler may complain */ |
429 | return -1; |
430 | } |
431 | #define kmalloc_index(s) __kmalloc_index(s, true) |
432 | #endif /* !CONFIG_SLOB */ |
433 | |
434 | void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); |
435 | void *kmem_cache_alloc(struct kmem_cache *s, gfp_t flags) __assume_slab_alignment __malloc; |
436 | void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, |
437 | gfp_t gfpflags) __assume_slab_alignment __malloc; |
438 | void kmem_cache_free(struct kmem_cache *s, void *objp); |
439 | |
440 | /* |
441 | * Bulk allocation and freeing operations. These are accelerated in an |
442 | * allocator specific way to avoid taking locks repeatedly or building |
443 | * metadata structures unnecessarily. |
444 | * |
445 | * Note that interrupts must be enabled when calling these functions. |
446 | */ |
447 | void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p); |
448 | int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, void **p); |
449 | |
450 | /* |
451 | * Caller must not use kfree_bulk() on memory not originally allocated |
452 | * by kmalloc(), because the SLOB allocator cannot handle this. |
453 | */ |
454 | static __always_inline void kfree_bulk(size_t size, void **p) |
455 | { |
456 | kmem_cache_free_bulk(NULL, size, p); |
457 | } |
458 | |
459 | #ifdef CONFIG_NUMA |
460 | void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment |
461 | __alloc_size(1); |
462 | void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node) __assume_slab_alignment |
463 | __malloc; |
464 | #else |
465 | static __always_inline __alloc_size(1) void *__kmalloc_node(size_t size, gfp_t flags, int node) |
466 | { |
467 | return __kmalloc(size, flags); |
468 | } |
469 | |
470 | static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node) |
471 | { |
472 | return kmem_cache_alloc(s, flags); |
473 | } |
474 | #endif |
475 | |
476 | #ifdef CONFIG_TRACING |
477 | extern void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t flags, size_t size) |
478 | __assume_slab_alignment __alloc_size(3); |
479 | |
480 | #ifdef CONFIG_NUMA |
481 | extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, |
482 | int node, size_t size) __assume_slab_alignment |
483 | __alloc_size(4); |
484 | #else |
485 | static __always_inline __alloc_size(4) void *kmem_cache_alloc_node_trace(struct kmem_cache *s, |
486 | gfp_t gfpflags, int node, size_t size) |
487 | { |
488 | return kmem_cache_alloc_trace(s, gfpflags, size); |
489 | } |
490 | #endif /* CONFIG_NUMA */ |
491 | |
492 | #else /* CONFIG_TRACING */ |
493 | static __always_inline __alloc_size(3) void *kmem_cache_alloc_trace(struct kmem_cache *s, |
494 | gfp_t flags, size_t size) |
495 | { |
496 | void *ret = kmem_cache_alloc(s, flags); |
497 | |
498 | ret = kasan_kmalloc(s, ret, size, flags); |
499 | return ret; |
500 | } |
501 | |
502 | static __always_inline void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, |
503 | int node, size_t size) |
504 | { |
505 | void *ret = kmem_cache_alloc_node(s, gfpflags, node); |
506 | |
507 | ret = kasan_kmalloc(s, ret, size, gfpflags); |
508 | return ret; |
509 | } |
510 | #endif /* CONFIG_TRACING */ |
511 | |
512 | extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment |
513 | __alloc_size(1); |
514 | |
515 | #ifdef CONFIG_TRACING |
516 | extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) |
517 | __assume_page_alignment __alloc_size(1); |
518 | #else |
519 | static __always_inline __alloc_size(1) void *kmalloc_order_trace(size_t size, gfp_t flags, |
520 | unsigned int order) |
521 | { |
522 | return kmalloc_order(size, flags, order); |
523 | } |
524 | #endif |
525 | |
526 | static __always_inline __alloc_size(1) void *kmalloc_large(size_t size, gfp_t flags) |
527 | { |
528 | unsigned int order = get_order(size); |
529 | return kmalloc_order_trace(size, flags, order); |
530 | } |
531 | |
532 | /** |
533 | * kmalloc - allocate memory |
534 | * @size: how many bytes of memory are required. |
535 | * @flags: the type of memory to allocate. |
536 | * |
537 | * kmalloc is the normal method of allocating memory |
538 | * for objects smaller than page size in the kernel. |
539 | * |
540 | * The allocated object address is aligned to at least ARCH_KMALLOC_MINALIGN |
541 | * bytes. For @size of power of two bytes, the alignment is also guaranteed |
542 | * to be at least to the size. |
543 | * |
544 | * The @flags argument may be one of the GFP flags defined at |
545 | * include/linux/gfp.h and described at |
546 | * :ref:`Documentation/core-api/mm-api.rst <mm-api-gfp-flags>` |
547 | * |
548 | * The recommended usage of the @flags is described at |
549 | * :ref:`Documentation/core-api/memory-allocation.rst <memory_allocation>` |
550 | * |
551 | * Below is a brief outline of the most useful GFP flags |
552 | * |
553 | * %GFP_KERNEL |
554 | * Allocate normal kernel ram. May sleep. |
555 | * |
556 | * %GFP_NOWAIT |
557 | * Allocation will not sleep. |
558 | * |
559 | * %GFP_ATOMIC |
560 | * Allocation will not sleep. May use emergency pools. |
561 | * |
562 | * %GFP_HIGHUSER |
563 | * Allocate memory from high memory on behalf of user. |
564 | * |
565 | * Also it is possible to set different flags by OR'ing |
566 | * in one or more of the following additional @flags: |
567 | * |
568 | * %__GFP_HIGH |
569 | * This allocation has high priority and may use emergency pools. |
570 | * |
571 | * %__GFP_NOFAIL |
572 | * Indicate that this allocation is in no way allowed to fail |
573 | * (think twice before using). |
574 | * |
575 | * %__GFP_NORETRY |
576 | * If memory is not immediately available, |
577 | * then give up at once. |
578 | * |
579 | * %__GFP_NOWARN |
580 | * If allocation fails, don't issue any warnings. |
581 | * |
582 | * %__GFP_RETRY_MAYFAIL |
583 | * Try really hard to succeed the allocation but fail |
584 | * eventually. |
585 | */ |
586 | static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) |
587 | { |
588 | if (__builtin_constant_p(size)) { |
589 | #ifndef CONFIG_SLOB |
590 | unsigned int index; |
591 | #endif |
592 | if (size > KMALLOC_MAX_CACHE_SIZE) |
593 | return kmalloc_large(size, flags); |
594 | #ifndef CONFIG_SLOB |
595 | index = kmalloc_index(size); |
596 | |
597 | if (!index) |
598 | return ZERO_SIZE_PTR; |
599 | |
600 | return kmem_cache_alloc_trace( |
601 | kmalloc_caches[kmalloc_type(flags)][index], |
602 | flags, size); |
603 | #endif |
604 | } |
605 | return __kmalloc(size, flags); |
606 | } |
607 | |
608 | static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) |
609 | { |
610 | #ifndef CONFIG_SLOB |
611 | if (__builtin_constant_p(size) && |
612 | size <= KMALLOC_MAX_CACHE_SIZE) { |
613 | unsigned int i = kmalloc_index(size); |
614 | |
615 | if (!i) |
616 | return ZERO_SIZE_PTR; |
617 | |
618 | return kmem_cache_alloc_node_trace( |
619 | kmalloc_caches[kmalloc_type(flags)][i], |
620 | flags, node, size); |
621 | } |
622 | #endif |
623 | return __kmalloc_node(size, flags, node); |
624 | } |
625 | |
626 | /** |
627 | * kmalloc_array - allocate memory for an array. |
628 | * @n: number of elements. |
629 | * @size: element size. |
630 | * @flags: the type of memory to allocate (see kmalloc). |
631 | */ |
632 | static inline __alloc_size(1, 2) void *kmalloc_array(size_t n, size_t size, gfp_t flags) |
633 | { |
634 | size_t bytes; |
635 | |
636 | if (unlikely(check_mul_overflow(n, size, &bytes))) |
637 | return NULL; |
638 | if (__builtin_constant_p(n) && __builtin_constant_p(size)) |
639 | return kmalloc(bytes, flags); |
640 | return __kmalloc(bytes, flags); |
641 | } |
642 | |
643 | /** |
644 | * krealloc_array - reallocate memory for an array. |
645 | * @p: pointer to the memory chunk to reallocate |
646 | * @new_n: new number of elements to alloc |
647 | * @new_size: new size of a single member of the array |
648 | * @flags: the type of memory to allocate (see kmalloc) |
649 | */ |
650 | static inline __alloc_size(2, 3) void * __must_check krealloc_array(void *p, |
651 | size_t new_n, |
652 | size_t new_size, |
653 | gfp_t flags) |
654 | { |
655 | size_t bytes; |
656 | |
657 | if (unlikely(check_mul_overflow(new_n, new_size, &bytes))) |
658 | return NULL; |
659 | |
660 | return krealloc(p, bytes, flags); |
661 | } |
662 | |
663 | /** |
664 | * kcalloc - allocate memory for an array. The memory is set to zero. |
665 | * @n: number of elements. |
666 | * @size: element size. |
667 | * @flags: the type of memory to allocate (see kmalloc). |
668 | */ |
669 | static inline __alloc_size(1, 2) void *kcalloc(size_t n, size_t size, gfp_t flags) |
670 | { |
671 | return kmalloc_array(n, size, flags | __GFP_ZERO); |
672 | } |
673 | |
674 | /* |
675 | * kmalloc_track_caller is a special version of kmalloc that records the |
676 | * calling function of the routine calling it for slab leak tracking instead |
677 | * of just the calling function (confusing, eh?). |
678 | * It's useful when the call to kmalloc comes from a widely-used standard |
679 | * allocator where we care about the real place the memory allocation |
680 | * request comes from. |
681 | */ |
682 | extern void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller); |
683 | #define kmalloc_track_caller(size, flags) \ |
684 | __kmalloc_track_caller(size, flags, _RET_IP_) |
685 | |
686 | static inline __alloc_size(1, 2) void *kmalloc_array_node(size_t n, size_t size, gfp_t flags, |
687 | int node) |
688 | { |
689 | size_t bytes; |
690 | |
691 | if (unlikely(check_mul_overflow(n, size, &bytes))) |
692 | return NULL; |
693 | if (__builtin_constant_p(n) && __builtin_constant_p(size)) |
694 | return kmalloc_node(bytes, flags, node); |
695 | return __kmalloc_node(bytes, flags, node); |
696 | } |
697 | |
698 | static inline __alloc_size(1, 2) void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node) |
699 | { |
700 | return kmalloc_array_node(n, size, flags | __GFP_ZERO, node); |
701 | } |
702 | |
703 | |
704 | #ifdef CONFIG_NUMA |
705 | extern void *__kmalloc_node_track_caller(size_t size, gfp_t flags, int node, |
706 | unsigned long caller) __alloc_size(1); |
707 | #define kmalloc_node_track_caller(size, flags, node) \ |
708 | __kmalloc_node_track_caller(size, flags, node, \ |
709 | _RET_IP_) |
710 | |
711 | #else /* CONFIG_NUMA */ |
712 | |
713 | #define kmalloc_node_track_caller(size, flags, node) \ |
714 | kmalloc_track_caller(size, flags) |
715 | |
716 | #endif /* CONFIG_NUMA */ |
717 | |
718 | /* |
719 | * Shortcuts |
720 | */ |
721 | static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags) |
722 | { |
723 | return kmem_cache_alloc(k, flags | __GFP_ZERO); |
724 | } |
725 | |
726 | /** |
727 | * kzalloc - allocate memory. The memory is set to zero. |
728 | * @size: how many bytes of memory are required. |
729 | * @flags: the type of memory to allocate (see kmalloc). |
730 | */ |
731 | static inline __alloc_size(1) void *kzalloc(size_t size, gfp_t flags) |
732 | { |
733 | return kmalloc(size, flags | __GFP_ZERO); |
734 | } |
735 | |
736 | /** |
737 | * kzalloc_node - allocate zeroed memory from a particular memory node. |
738 | * @size: how many bytes of memory are required. |
739 | * @flags: the type of memory to allocate (see kmalloc). |
740 | * @node: memory node from which to allocate |
741 | */ |
742 | static inline __alloc_size(1) void *kzalloc_node(size_t size, gfp_t flags, int node) |
743 | { |
744 | return kmalloc_node(size, flags | __GFP_ZERO, node); |
745 | } |
746 | |
747 | extern void *kvmalloc_node(size_t size, gfp_t flags, int node) __alloc_size(1); |
748 | static inline __alloc_size(1) void *kvmalloc(size_t size, gfp_t flags) |
749 | { |
750 | return kvmalloc_node(size, flags, NUMA_NO_NODE); |
751 | } |
752 | static inline __alloc_size(1) void *kvzalloc_node(size_t size, gfp_t flags, int node) |
753 | { |
754 | return kvmalloc_node(size, flags | __GFP_ZERO, node); |
755 | } |
756 | static inline __alloc_size(1) void *kvzalloc(size_t size, gfp_t flags) |
757 | { |
758 | return kvmalloc(size, flags | __GFP_ZERO); |
759 | } |
760 | |
761 | static inline __alloc_size(1, 2) void *kvmalloc_array(size_t n, size_t size, gfp_t flags) |
762 | { |
763 | size_t bytes; |
764 | |
765 | if (unlikely(check_mul_overflow(n, size, &bytes))) |
766 | return NULL; |
767 | |
768 | return kvmalloc(bytes, flags); |
769 | } |
770 | |
771 | static inline __alloc_size(1, 2) void *kvcalloc(size_t n, size_t size, gfp_t flags) |
772 | { |
773 | return kvmalloc_array(n, size, flags | __GFP_ZERO); |
774 | } |
775 | |
776 | extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize, gfp_t flags) |
777 | __alloc_size(3); |
778 | extern void kvfree(const void *addr); |
779 | extern void kvfree_sensitive(const void *addr, size_t len); |
780 | |
781 | unsigned int kmem_cache_size(struct kmem_cache *s); |
782 | void __init kmem_cache_init_late(void); |
783 | |
784 | #if defined(CONFIG_SMP) && defined(CONFIG_SLAB) |
785 | int slab_prepare_cpu(unsigned int cpu); |
786 | int slab_dead_cpu(unsigned int cpu); |
787 | #else |
788 | #define slab_prepare_cpu NULL |
789 | #define slab_dead_cpu NULL |
790 | #endif |
791 | |
792 | #endif /* _LINUX_SLAB_H */ |
793 | |