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/cache.h>
16 #include <linux/gfp.h>
17 #include <linux/overflow.h>
18 #include <linux/types.h>
19 #include <linux/rcupdate.h>
20 #include <linux/workqueue.h>
21 #include <linux/percpu-refcount.h>
22 #include <linux/cleanup.h>
23 #include <linux/hash.h>
24
25 enum _slab_flag_bits {
26 _SLAB_CONSISTENCY_CHECKS,
27 _SLAB_RED_ZONE,
28 _SLAB_POISON,
29 _SLAB_KMALLOC,
30 _SLAB_HWCACHE_ALIGN,
31 _SLAB_CACHE_DMA,
32 _SLAB_CACHE_DMA32,
33 _SLAB_STORE_USER,
34 _SLAB_PANIC,
35 _SLAB_TYPESAFE_BY_RCU,
36 _SLAB_TRACE,
37 #ifdef CONFIG_DEBUG_OBJECTS
38 _SLAB_DEBUG_OBJECTS,
39 #endif
40 _SLAB_NOLEAKTRACE,
41 _SLAB_NO_MERGE,
42 #ifdef CONFIG_FAILSLAB
43 _SLAB_FAILSLAB,
44 #endif
45 #ifdef CONFIG_MEMCG
46 _SLAB_ACCOUNT,
47 #endif
48 #ifdef CONFIG_KASAN_GENERIC
49 _SLAB_KASAN,
50 #endif
51 _SLAB_NO_USER_FLAGS,
52 #ifdef CONFIG_KFENCE
53 _SLAB_SKIP_KFENCE,
54 #endif
55 #ifndef CONFIG_SLUB_TINY
56 _SLAB_RECLAIM_ACCOUNT,
57 #endif
58 _SLAB_OBJECT_POISON,
59 _SLAB_CMPXCHG_DOUBLE,
60 #ifdef CONFIG_SLAB_OBJ_EXT
61 _SLAB_NO_OBJ_EXT,
62 #endif
63 _SLAB_FLAGS_LAST_BIT
64 };
65
66 #define __SLAB_FLAG_BIT(nr) ((slab_flags_t __force)(1U << (nr)))
67 #define __SLAB_FLAG_UNUSED ((slab_flags_t __force)(0U))
68
69 /*
70 * Flags to pass to kmem_cache_create().
71 * The ones marked DEBUG need CONFIG_SLUB_DEBUG enabled, otherwise are no-op
72 */
73 /* DEBUG: Perform (expensive) checks on alloc/free */
74 #define SLAB_CONSISTENCY_CHECKS __SLAB_FLAG_BIT(_SLAB_CONSISTENCY_CHECKS)
75 /* DEBUG: Red zone objs in a cache */
76 #define SLAB_RED_ZONE __SLAB_FLAG_BIT(_SLAB_RED_ZONE)
77 /* DEBUG: Poison objects */
78 #define SLAB_POISON __SLAB_FLAG_BIT(_SLAB_POISON)
79 /* Indicate a kmalloc slab */
80 #define SLAB_KMALLOC __SLAB_FLAG_BIT(_SLAB_KMALLOC)
81 /**
82 * define SLAB_HWCACHE_ALIGN - Align objects on cache line boundaries.
83 *
84 * Sufficiently large objects are aligned on cache line boundary. For object
85 * size smaller than a half of cache line size, the alignment is on the half of
86 * cache line size. In general, if object size is smaller than 1/2^n of cache
87 * line size, the alignment is adjusted to 1/2^n.
88 *
89 * If explicit alignment is also requested by the respective
90 * &struct kmem_cache_args field, the greater of both is alignments is applied.
91 */
92 #define SLAB_HWCACHE_ALIGN __SLAB_FLAG_BIT(_SLAB_HWCACHE_ALIGN)
93 /* Use GFP_DMA memory */
94 #define SLAB_CACHE_DMA __SLAB_FLAG_BIT(_SLAB_CACHE_DMA)
95 /* Use GFP_DMA32 memory */
96 #define SLAB_CACHE_DMA32 __SLAB_FLAG_BIT(_SLAB_CACHE_DMA32)
97 /* DEBUG: Store the last owner for bug hunting */
98 #define SLAB_STORE_USER __SLAB_FLAG_BIT(_SLAB_STORE_USER)
99 /* Panic if kmem_cache_create() fails */
100 #define SLAB_PANIC __SLAB_FLAG_BIT(_SLAB_PANIC)
101 /**
102 * define SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
103 *
104 * This delays freeing the SLAB page by a grace period, it does _NOT_
105 * delay object freeing. This means that if you do kmem_cache_free()
106 * that memory location is free to be reused at any time. Thus it may
107 * be possible to see another object there in the same RCU grace period.
108 *
109 * This feature only ensures the memory location backing the object
110 * stays valid, the trick to using this is relying on an independent
111 * object validation pass. Something like:
112 *
113 * ::
114 *
115 * begin:
116 * rcu_read_lock();
117 * obj = lockless_lookup(key);
118 * if (obj) {
119 * if (!try_get_ref(obj)) // might fail for free objects
120 * rcu_read_unlock();
121 * goto begin;
122 *
123 * if (obj->key != key) { // not the object we expected
124 * put_ref(obj);
125 * rcu_read_unlock();
126 * goto begin;
127 * }
128 * }
129 * rcu_read_unlock();
130 *
131 * This is useful if we need to approach a kernel structure obliquely,
132 * from its address obtained without the usual locking. We can lock
133 * the structure to stabilize it and check it's still at the given address,
134 * only if we can be sure that the memory has not been meanwhile reused
135 * for some other kind of object (which our subsystem's lock might corrupt).
136 *
137 * rcu_read_lock before reading the address, then rcu_read_unlock after
138 * taking the spinlock within the structure expected at that address.
139 *
140 * Note that object identity check has to be done *after* acquiring a
141 * reference, therefore user has to ensure proper ordering for loads.
142 * Similarly, when initializing objects allocated with SLAB_TYPESAFE_BY_RCU,
143 * the newly allocated object has to be fully initialized *before* its
144 * refcount gets initialized and proper ordering for stores is required.
145 * refcount_{add|inc}_not_zero_acquire() and refcount_set_release() are
146 * designed with the proper fences required for reference counting objects
147 * allocated with SLAB_TYPESAFE_BY_RCU.
148 *
149 * Note that it is not possible to acquire a lock within a structure
150 * allocated with SLAB_TYPESAFE_BY_RCU without first acquiring a reference
151 * as described above. The reason is that SLAB_TYPESAFE_BY_RCU pages
152 * are not zeroed before being given to the slab, which means that any
153 * locks must be initialized after each and every kmem_struct_alloc().
154 * Alternatively, make the ctor passed to kmem_cache_create() initialize
155 * the locks at page-allocation time, as is done in __i915_request_ctor(),
156 * sighand_ctor(), and anon_vma_ctor(). Such a ctor permits readers
157 * to safely acquire those ctor-initialized locks under rcu_read_lock()
158 * protection.
159 *
160 * Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
161 */
162 #define SLAB_TYPESAFE_BY_RCU __SLAB_FLAG_BIT(_SLAB_TYPESAFE_BY_RCU)
163 /* Trace allocations and frees */
164 #define SLAB_TRACE __SLAB_FLAG_BIT(_SLAB_TRACE)
165
166 /* Flag to prevent checks on free */
167 #ifdef CONFIG_DEBUG_OBJECTS
168 # define SLAB_DEBUG_OBJECTS __SLAB_FLAG_BIT(_SLAB_DEBUG_OBJECTS)
169 #else
170 # define SLAB_DEBUG_OBJECTS __SLAB_FLAG_UNUSED
171 #endif
172
173 /* Avoid kmemleak tracing */
174 #define SLAB_NOLEAKTRACE __SLAB_FLAG_BIT(_SLAB_NOLEAKTRACE)
175
176 /*
177 * Prevent merging with compatible kmem caches. This flag should be used
178 * cautiously. Valid use cases:
179 *
180 * - caches created for self-tests (e.g. kunit)
181 * - general caches created and used by a subsystem, only when a
182 * (subsystem-specific) debug option is enabled
183 * - performance critical caches, should be very rare and consulted with slab
184 * maintainers, and not used together with CONFIG_SLUB_TINY
185 */
186 #define SLAB_NO_MERGE __SLAB_FLAG_BIT(_SLAB_NO_MERGE)
187
188 /* Fault injection mark */
189 #ifdef CONFIG_FAILSLAB
190 # define SLAB_FAILSLAB __SLAB_FLAG_BIT(_SLAB_FAILSLAB)
191 #else
192 # define SLAB_FAILSLAB __SLAB_FLAG_UNUSED
193 #endif
194 /**
195 * define SLAB_ACCOUNT - Account allocations to memcg.
196 *
197 * All object allocations from this cache will be memcg accounted, regardless of
198 * __GFP_ACCOUNT being or not being passed to individual allocations.
199 */
200 #ifdef CONFIG_MEMCG
201 # define SLAB_ACCOUNT __SLAB_FLAG_BIT(_SLAB_ACCOUNT)
202 #else
203 # define SLAB_ACCOUNT __SLAB_FLAG_UNUSED
204 #endif
205
206 #ifdef CONFIG_KASAN_GENERIC
207 #define SLAB_KASAN __SLAB_FLAG_BIT(_SLAB_KASAN)
208 #else
209 #define SLAB_KASAN __SLAB_FLAG_UNUSED
210 #endif
211
212 /*
213 * Ignore user specified debugging flags.
214 * Intended for caches created for self-tests so they have only flags
215 * specified in the code and other flags are ignored.
216 */
217 #define SLAB_NO_USER_FLAGS __SLAB_FLAG_BIT(_SLAB_NO_USER_FLAGS)
218
219 #ifdef CONFIG_KFENCE
220 #define SLAB_SKIP_KFENCE __SLAB_FLAG_BIT(_SLAB_SKIP_KFENCE)
221 #else
222 #define SLAB_SKIP_KFENCE __SLAB_FLAG_UNUSED
223 #endif
224
225 /* The following flags affect the page allocator grouping pages by mobility */
226 /**
227 * define SLAB_RECLAIM_ACCOUNT - Objects are reclaimable.
228 *
229 * Use this flag for caches that have an associated shrinker. As a result, slab
230 * pages are allocated with __GFP_RECLAIMABLE, which affects grouping pages by
231 * mobility, and are accounted in SReclaimable counter in /proc/meminfo
232 */
233 #ifndef CONFIG_SLUB_TINY
234 #define SLAB_RECLAIM_ACCOUNT __SLAB_FLAG_BIT(_SLAB_RECLAIM_ACCOUNT)
235 #else
236 #define SLAB_RECLAIM_ACCOUNT __SLAB_FLAG_UNUSED
237 #endif
238 #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
239
240 /* Slab created using create_boot_cache */
241 #ifdef CONFIG_SLAB_OBJ_EXT
242 #define SLAB_NO_OBJ_EXT __SLAB_FLAG_BIT(_SLAB_NO_OBJ_EXT)
243 #else
244 #define SLAB_NO_OBJ_EXT __SLAB_FLAG_UNUSED
245 #endif
246
247 /*
248 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
249 *
250 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
251 *
252 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
253 * Both make kfree a no-op.
254 */
255 #define ZERO_SIZE_PTR ((void *)16)
256
257 #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
258 (unsigned long)ZERO_SIZE_PTR)
259
260 #include <linux/kasan.h>
261
262 struct list_lru;
263 struct mem_cgroup;
264 /*
265 * struct kmem_cache related prototypes
266 */
267 bool slab_is_available(void);
268
269 /**
270 * struct kmem_cache_args - Less common arguments for kmem_cache_create()
271 *
272 * Any uninitialized fields of the structure are interpreted as unused. The
273 * exception is @freeptr_offset where %0 is a valid value, so
274 * @use_freeptr_offset must be also set to %true in order to interpret the field
275 * as used. For @useroffset %0 is also valid, but only with non-%0
276 * @usersize.
277 *
278 * When %NULL args is passed to kmem_cache_create(), it is equivalent to all
279 * fields unused.
280 */
281 struct kmem_cache_args {
282 /**
283 * @align: The required alignment for the objects.
284 *
285 * %0 means no specific alignment is requested.
286 */
287 unsigned int align;
288 /**
289 * @useroffset: Usercopy region offset.
290 *
291 * %0 is a valid offset, when @usersize is non-%0
292 */
293 unsigned int useroffset;
294 /**
295 * @usersize: Usercopy region size.
296 *
297 * %0 means no usercopy region is specified.
298 */
299 unsigned int usersize;
300 /**
301 * @freeptr_offset: Custom offset for the free pointer
302 * in &SLAB_TYPESAFE_BY_RCU caches
303 *
304 * By default &SLAB_TYPESAFE_BY_RCU caches place the free pointer
305 * outside of the object. This might cause the object to grow in size.
306 * Cache creators that have a reason to avoid this can specify a custom
307 * free pointer offset in their struct where the free pointer will be
308 * placed.
309 *
310 * Note that placing the free pointer inside the object requires the
311 * caller to ensure that no fields are invalidated that are required to
312 * guard against object recycling (See &SLAB_TYPESAFE_BY_RCU for
313 * details).
314 *
315 * Using %0 as a value for @freeptr_offset is valid. If @freeptr_offset
316 * is specified, %use_freeptr_offset must be set %true.
317 *
318 * Note that @ctor currently isn't supported with custom free pointers
319 * as a @ctor requires an external free pointer.
320 */
321 unsigned int freeptr_offset;
322 /**
323 * @use_freeptr_offset: Whether a @freeptr_offset is used.
324 */
325 bool use_freeptr_offset;
326 /**
327 * @ctor: A constructor for the objects.
328 *
329 * The constructor is invoked for each object in a newly allocated slab
330 * page. It is the cache user's responsibility to free object in the
331 * same state as after calling the constructor, or deal appropriately
332 * with any differences between a freshly constructed and a reallocated
333 * object.
334 *
335 * %NULL means no constructor.
336 */
337 void (*ctor)(void *);
338 /**
339 * @sheaf_capacity: Enable sheaves of given capacity for the cache.
340 *
341 * With a non-zero value, allocations from the cache go through caching
342 * arrays called sheaves. Each cpu has a main sheaf that's always
343 * present, and a spare sheaf that may be not present. When both become
344 * empty, there's an attempt to replace an empty sheaf with a full sheaf
345 * from the per-node barn.
346 *
347 * When no full sheaf is available, and gfp flags allow blocking, a
348 * sheaf is allocated and filled from slab(s) using bulk allocation.
349 * Otherwise the allocation falls back to the normal operation
350 * allocating a single object from a slab.
351 *
352 * Analogically when freeing and both percpu sheaves are full, the barn
353 * may replace it with an empty sheaf, unless it's over capacity. In
354 * that case a sheaf is bulk freed to slab pages.
355 *
356 * The sheaves do not enforce NUMA placement of objects, so allocations
357 * via kmem_cache_alloc_node() with a node specified other than
358 * NUMA_NO_NODE will bypass them.
359 *
360 * Bulk allocation and free operations also try to use the cpu sheaves
361 * and barn, but fallback to using slab pages directly.
362 *
363 * When slub_debug is enabled for the cache, the sheaf_capacity argument
364 * is ignored.
365 *
366 * %0 means no sheaves will be created.
367 */
368 unsigned int sheaf_capacity;
369 };
370
371 struct kmem_cache *__kmem_cache_create_args(const char *name,
372 unsigned int object_size,
373 struct kmem_cache_args *args,
374 slab_flags_t flags);
375 static inline struct kmem_cache *
__kmem_cache_create(const char * name,unsigned int size,unsigned int align,slab_flags_t flags,void (* ctor)(void *))376 __kmem_cache_create(const char *name, unsigned int size, unsigned int align,
377 slab_flags_t flags, void (*ctor)(void *))
378 {
379 struct kmem_cache_args kmem_args = {
380 .align = align,
381 .ctor = ctor,
382 };
383
384 return __kmem_cache_create_args(name, size, &kmem_args, flags);
385 }
386
387 /**
388 * kmem_cache_create_usercopy - Create a kmem cache with a region suitable
389 * for copying to userspace.
390 * @name: A string which is used in /proc/slabinfo to identify this cache.
391 * @size: The size of objects to be created in this cache.
392 * @align: The required alignment for the objects.
393 * @flags: SLAB flags
394 * @useroffset: Usercopy region offset
395 * @usersize: Usercopy region size
396 * @ctor: A constructor for the objects, or %NULL.
397 *
398 * This is a legacy wrapper, new code should use either KMEM_CACHE_USERCOPY()
399 * if whitelisting a single field is sufficient, or kmem_cache_create() with
400 * the necessary parameters passed via the args parameter (see
401 * &struct kmem_cache_args)
402 *
403 * Return: a pointer to the cache on success, NULL on failure.
404 */
405 static inline struct kmem_cache *
kmem_cache_create_usercopy(const char * name,unsigned int size,unsigned int align,slab_flags_t flags,unsigned int useroffset,unsigned int usersize,void (* ctor)(void *))406 kmem_cache_create_usercopy(const char *name, unsigned int size,
407 unsigned int align, slab_flags_t flags,
408 unsigned int useroffset, unsigned int usersize,
409 void (*ctor)(void *))
410 {
411 struct kmem_cache_args kmem_args = {
412 .align = align,
413 .ctor = ctor,
414 .useroffset = useroffset,
415 .usersize = usersize,
416 };
417
418 return __kmem_cache_create_args(name, size, &kmem_args, flags);
419 }
420
421 /* If NULL is passed for @args, use this variant with default arguments. */
422 static inline struct kmem_cache *
__kmem_cache_default_args(const char * name,unsigned int size,struct kmem_cache_args * args,slab_flags_t flags)423 __kmem_cache_default_args(const char *name, unsigned int size,
424 struct kmem_cache_args *args,
425 slab_flags_t flags)
426 {
427 struct kmem_cache_args kmem_default_args = {};
428
429 /* Make sure we don't get passed garbage. */
430 if (WARN_ON_ONCE(args))
431 return ERR_PTR(-EINVAL);
432
433 return __kmem_cache_create_args(name, size, &kmem_default_args, flags);
434 }
435
436 /**
437 * kmem_cache_create - Create a kmem cache.
438 * @__name: A string which is used in /proc/slabinfo to identify this cache.
439 * @__object_size: The size of objects to be created in this cache.
440 * @__args: Optional arguments, see &struct kmem_cache_args. Passing %NULL
441 * means defaults will be used for all the arguments.
442 *
443 * This is currently implemented as a macro using ``_Generic()`` to call
444 * either the new variant of the function, or a legacy one.
445 *
446 * The new variant has 4 parameters:
447 * ``kmem_cache_create(name, object_size, args, flags)``
448 *
449 * See __kmem_cache_create_args() which implements this.
450 *
451 * The legacy variant has 5 parameters:
452 * ``kmem_cache_create(name, object_size, align, flags, ctor)``
453 *
454 * The align and ctor parameters map to the respective fields of
455 * &struct kmem_cache_args
456 *
457 * Context: Cannot be called within a interrupt, but can be interrupted.
458 *
459 * Return: a pointer to the cache on success, NULL on failure.
460 */
461 #define kmem_cache_create(__name, __object_size, __args, ...) \
462 _Generic((__args), \
463 struct kmem_cache_args *: __kmem_cache_create_args, \
464 void *: __kmem_cache_default_args, \
465 default: __kmem_cache_create)(__name, __object_size, __args, __VA_ARGS__)
466
467 void kmem_cache_destroy(struct kmem_cache *s);
468 int kmem_cache_shrink(struct kmem_cache *s);
469
470 /*
471 * Please use this macro to create slab caches. Simply specify the
472 * name of the structure and maybe some flags that are listed above.
473 *
474 * The alignment of the struct determines object alignment. If you
475 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
476 * then the objects will be properly aligned in SMP configurations.
477 */
478 #define KMEM_CACHE(__struct, __flags) \
479 __kmem_cache_create_args(#__struct, sizeof(struct __struct), \
480 &(struct kmem_cache_args) { \
481 .align = __alignof__(struct __struct), \
482 }, (__flags))
483
484 /*
485 * To whitelist a single field for copying to/from usercopy, use this
486 * macro instead for KMEM_CACHE() above.
487 */
488 #define KMEM_CACHE_USERCOPY(__struct, __flags, __field) \
489 __kmem_cache_create_args(#__struct, sizeof(struct __struct), \
490 &(struct kmem_cache_args) { \
491 .align = __alignof__(struct __struct), \
492 .useroffset = offsetof(struct __struct, __field), \
493 .usersize = sizeof_field(struct __struct, __field), \
494 }, (__flags))
495
496 /*
497 * Common kmalloc functions provided by all allocators
498 */
499 void * __must_check krealloc_node_align_noprof(const void *objp, size_t new_size,
500 unsigned long align,
501 gfp_t flags, int nid) __realloc_size(2);
502 #define krealloc_noprof(_o, _s, _f) krealloc_node_align_noprof(_o, _s, 1, _f, NUMA_NO_NODE)
503 #define krealloc_node_align(...) alloc_hooks(krealloc_node_align_noprof(__VA_ARGS__))
504 #define krealloc_node(_o, _s, _f, _n) krealloc_node_align(_o, _s, 1, _f, _n)
505 #define krealloc(...) krealloc_node(__VA_ARGS__, NUMA_NO_NODE)
506
507 void kfree(const void *objp);
508 void kfree_nolock(const void *objp);
509 void kfree_sensitive(const void *objp);
510 size_t __ksize(const void *objp);
511
512 DEFINE_FREE(kfree, void *, if (!IS_ERR_OR_NULL(_T)) kfree(_T))
513 DEFINE_FREE(kfree_sensitive, void *, if (_T) kfree_sensitive(_T))
514
515 /**
516 * ksize - Report actual allocation size of associated object
517 *
518 * @objp: Pointer returned from a prior kmalloc()-family allocation.
519 *
520 * This should not be used for writing beyond the originally requested
521 * allocation size. Either use krealloc() or round up the allocation size
522 * with kmalloc_size_roundup() prior to allocation. If this is used to
523 * access beyond the originally requested allocation size, UBSAN_BOUNDS
524 * and/or FORTIFY_SOURCE may trip, since they only know about the
525 * originally allocated size via the __alloc_size attribute.
526 */
527 size_t ksize(const void *objp);
528
529 #ifdef CONFIG_PRINTK
530 bool kmem_dump_obj(void *object);
531 #else
kmem_dump_obj(void * object)532 static inline bool kmem_dump_obj(void *object) { return false; }
533 #endif
534
535 /*
536 * Some archs want to perform DMA into kmalloc caches and need a guaranteed
537 * alignment larger than the alignment of a 64-bit integer.
538 * Setting ARCH_DMA_MINALIGN in arch headers allows that.
539 */
540 #ifdef ARCH_HAS_DMA_MINALIGN
541 #if ARCH_DMA_MINALIGN > 8 && !defined(ARCH_KMALLOC_MINALIGN)
542 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
543 #endif
544 #endif
545
546 #ifndef ARCH_KMALLOC_MINALIGN
547 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
548 #elif ARCH_KMALLOC_MINALIGN > 8
549 #define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
550 #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
551 #endif
552
553 /*
554 * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
555 * Intended for arches that get misalignment faults even for 64 bit integer
556 * aligned buffers.
557 */
558 #ifndef ARCH_SLAB_MINALIGN
559 #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
560 #endif
561
562 /*
563 * Arches can define this function if they want to decide the minimum slab
564 * alignment at runtime. The value returned by the function must be a power
565 * of two and >= ARCH_SLAB_MINALIGN.
566 */
567 #ifndef arch_slab_minalign
arch_slab_minalign(void)568 static inline unsigned int arch_slab_minalign(void)
569 {
570 return ARCH_SLAB_MINALIGN;
571 }
572 #endif
573
574 /*
575 * kmem_cache_alloc and friends return pointers aligned to ARCH_SLAB_MINALIGN.
576 * kmalloc and friends return pointers aligned to both ARCH_KMALLOC_MINALIGN
577 * and ARCH_SLAB_MINALIGN, but here we only assume the former alignment.
578 */
579 #define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
580 #define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
581 #define __assume_page_alignment __assume_aligned(PAGE_SIZE)
582
583 /*
584 * Kmalloc array related definitions
585 */
586
587 /*
588 * SLUB directly allocates requests fitting in to an order-1 page
589 * (PAGE_SIZE*2). Larger requests are passed to the page allocator.
590 */
591 #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
592 #define KMALLOC_SHIFT_MAX (MAX_PAGE_ORDER + PAGE_SHIFT)
593 #ifndef KMALLOC_SHIFT_LOW
594 #define KMALLOC_SHIFT_LOW 3
595 #endif
596
597 /* Maximum allocatable size */
598 #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
599 /* Maximum size for which we actually use a slab cache */
600 #define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
601 /* Maximum order allocatable via the slab allocator */
602 #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
603
604 /*
605 * Kmalloc subsystem.
606 */
607 #ifndef KMALLOC_MIN_SIZE
608 #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
609 #endif
610
611 /*
612 * This restriction comes from byte sized index implementation.
613 * Page size is normally 2^12 bytes and, in this case, if we want to use
614 * byte sized index which can represent 2^8 entries, the size of the object
615 * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
616 * If minimum size of kmalloc is less than 16, we use it as minimum object
617 * size and give up to use byte sized index.
618 */
619 #define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
620 (KMALLOC_MIN_SIZE) : 16)
621
622 #ifdef CONFIG_RANDOM_KMALLOC_CACHES
623 #define RANDOM_KMALLOC_CACHES_NR 15 // # of cache copies
624 #else
625 #define RANDOM_KMALLOC_CACHES_NR 0
626 #endif
627
628 /*
629 * Whenever changing this, take care of that kmalloc_type() and
630 * create_kmalloc_caches() still work as intended.
631 *
632 * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP
633 * is for accounted but unreclaimable and non-dma objects. All the other
634 * kmem caches can have both accounted and unaccounted objects.
635 */
636 enum kmalloc_cache_type {
637 KMALLOC_NORMAL = 0,
638 #ifndef CONFIG_ZONE_DMA
639 KMALLOC_DMA = KMALLOC_NORMAL,
640 #endif
641 #ifndef CONFIG_MEMCG
642 KMALLOC_CGROUP = KMALLOC_NORMAL,
643 #endif
644 KMALLOC_RANDOM_START = KMALLOC_NORMAL,
645 KMALLOC_RANDOM_END = KMALLOC_RANDOM_START + RANDOM_KMALLOC_CACHES_NR,
646 #ifdef CONFIG_SLUB_TINY
647 KMALLOC_RECLAIM = KMALLOC_NORMAL,
648 #else
649 KMALLOC_RECLAIM,
650 #endif
651 #ifdef CONFIG_ZONE_DMA
652 KMALLOC_DMA,
653 #endif
654 #ifdef CONFIG_MEMCG
655 KMALLOC_CGROUP,
656 #endif
657 NR_KMALLOC_TYPES
658 };
659
660 typedef struct kmem_cache * kmem_buckets[KMALLOC_SHIFT_HIGH + 1];
661
662 extern kmem_buckets kmalloc_caches[NR_KMALLOC_TYPES];
663
664 /*
665 * Define gfp bits that should not be set for KMALLOC_NORMAL.
666 */
667 #define KMALLOC_NOT_NORMAL_BITS \
668 (__GFP_RECLAIMABLE | \
669 (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \
670 (IS_ENABLED(CONFIG_MEMCG) ? __GFP_ACCOUNT : 0))
671
672 extern unsigned long random_kmalloc_seed;
673
kmalloc_type(gfp_t flags,unsigned long caller)674 static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags, unsigned long caller)
675 {
676 /*
677 * The most common case is KMALLOC_NORMAL, so test for it
678 * with a single branch for all the relevant flags.
679 */
680 if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0))
681 #ifdef CONFIG_RANDOM_KMALLOC_CACHES
682 /* RANDOM_KMALLOC_CACHES_NR (=15) copies + the KMALLOC_NORMAL */
683 return KMALLOC_RANDOM_START + hash_64(caller ^ random_kmalloc_seed,
684 ilog2(RANDOM_KMALLOC_CACHES_NR + 1));
685 #else
686 return KMALLOC_NORMAL;
687 #endif
688
689 /*
690 * At least one of the flags has to be set. Their priorities in
691 * decreasing order are:
692 * 1) __GFP_DMA
693 * 2) __GFP_RECLAIMABLE
694 * 3) __GFP_ACCOUNT
695 */
696 if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA))
697 return KMALLOC_DMA;
698 if (!IS_ENABLED(CONFIG_MEMCG) || (flags & __GFP_RECLAIMABLE))
699 return KMALLOC_RECLAIM;
700 else
701 return KMALLOC_CGROUP;
702 }
703
704 /*
705 * Figure out which kmalloc slab an allocation of a certain size
706 * belongs to.
707 * 0 = zero alloc
708 * 1 = 65 .. 96 bytes
709 * 2 = 129 .. 192 bytes
710 * n = 2^(n-1)+1 .. 2^n
711 *
712 * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized;
713 * typical usage is via kmalloc_index() and therefore evaluated at compile-time.
714 * Callers where !size_is_constant should only be test modules, where runtime
715 * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab().
716 */
__kmalloc_index(size_t size,bool size_is_constant)717 static __always_inline unsigned int __kmalloc_index(size_t size,
718 bool size_is_constant)
719 {
720 if (!size)
721 return 0;
722
723 if (size <= KMALLOC_MIN_SIZE)
724 return KMALLOC_SHIFT_LOW;
725
726 if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
727 return 1;
728 if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
729 return 2;
730 if (size <= 8) return 3;
731 if (size <= 16) return 4;
732 if (size <= 32) return 5;
733 if (size <= 64) return 6;
734 if (size <= 128) return 7;
735 if (size <= 256) return 8;
736 if (size <= 512) return 9;
737 if (size <= 1024) return 10;
738 if (size <= 2 * 1024) return 11;
739 if (size <= 4 * 1024) return 12;
740 if (size <= 8 * 1024) return 13;
741 if (size <= 16 * 1024) return 14;
742 if (size <= 32 * 1024) return 15;
743 if (size <= 64 * 1024) return 16;
744 if (size <= 128 * 1024) return 17;
745 if (size <= 256 * 1024) return 18;
746 if (size <= 512 * 1024) return 19;
747 if (size <= 1024 * 1024) return 20;
748 if (size <= 2 * 1024 * 1024) return 21;
749
750 if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant)
751 BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()");
752 else
753 BUG();
754
755 /* Will never be reached. Needed because the compiler may complain */
756 return -1;
757 }
758 static_assert(PAGE_SHIFT <= 20);
759 #define kmalloc_index(s) __kmalloc_index(s, true)
760
761 #include <linux/alloc_tag.h>
762
763 /**
764 * kmem_cache_alloc - Allocate an object
765 * @cachep: The cache to allocate from.
766 * @flags: See kmalloc().
767 *
768 * Allocate an object from this cache.
769 * See kmem_cache_zalloc() for a shortcut of adding __GFP_ZERO to flags.
770 *
771 * Return: pointer to the new object or %NULL in case of error
772 */
773 void *kmem_cache_alloc_noprof(struct kmem_cache *cachep,
774 gfp_t flags) __assume_slab_alignment __malloc;
775 #define kmem_cache_alloc(...) alloc_hooks(kmem_cache_alloc_noprof(__VA_ARGS__))
776
777 void *kmem_cache_alloc_lru_noprof(struct kmem_cache *s, struct list_lru *lru,
778 gfp_t gfpflags) __assume_slab_alignment __malloc;
779 #define kmem_cache_alloc_lru(...) alloc_hooks(kmem_cache_alloc_lru_noprof(__VA_ARGS__))
780
781 /**
782 * kmem_cache_charge - memcg charge an already allocated slab memory
783 * @objp: address of the slab object to memcg charge
784 * @gfpflags: describe the allocation context
785 *
786 * kmem_cache_charge allows charging a slab object to the current memcg,
787 * primarily in cases where charging at allocation time might not be possible
788 * because the target memcg is not known (i.e. softirq context)
789 *
790 * The objp should be pointer returned by the slab allocator functions like
791 * kmalloc (with __GFP_ACCOUNT in flags) or kmem_cache_alloc. The memcg charge
792 * behavior can be controlled through gfpflags parameter, which affects how the
793 * necessary internal metadata can be allocated. Including __GFP_NOFAIL denotes
794 * that overcharging is requested instead of failure, but is not applied for the
795 * internal metadata allocation.
796 *
797 * There are several cases where it will return true even if the charging was
798 * not done:
799 * More specifically:
800 *
801 * 1. For !CONFIG_MEMCG or cgroup_disable=memory systems.
802 * 2. Already charged slab objects.
803 * 3. For slab objects from KMALLOC_NORMAL caches - allocated by kmalloc()
804 * without __GFP_ACCOUNT
805 * 4. Allocating internal metadata has failed
806 *
807 * Return: true if charge was successful otherwise false.
808 */
809 bool kmem_cache_charge(void *objp, gfp_t gfpflags);
810 void kmem_cache_free(struct kmem_cache *s, void *objp);
811
812 kmem_buckets *kmem_buckets_create(const char *name, slab_flags_t flags,
813 unsigned int useroffset, unsigned int usersize,
814 void (*ctor)(void *));
815
816 /*
817 * Bulk allocation and freeing operations. These are accelerated in an
818 * allocator specific way to avoid taking locks repeatedly or building
819 * metadata structures unnecessarily.
820 *
821 * Note that interrupts must be enabled when calling these functions.
822 */
823 void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p);
824
825 int kmem_cache_alloc_bulk_noprof(struct kmem_cache *s, gfp_t flags, size_t size, void **p);
826 #define kmem_cache_alloc_bulk(...) alloc_hooks(kmem_cache_alloc_bulk_noprof(__VA_ARGS__))
827
kfree_bulk(size_t size,void ** p)828 static __always_inline void kfree_bulk(size_t size, void **p)
829 {
830 kmem_cache_free_bulk(NULL, size, p);
831 }
832
833 void *kmem_cache_alloc_node_noprof(struct kmem_cache *s, gfp_t flags,
834 int node) __assume_slab_alignment __malloc;
835 #define kmem_cache_alloc_node(...) alloc_hooks(kmem_cache_alloc_node_noprof(__VA_ARGS__))
836
837 struct slab_sheaf *
838 kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size);
839
840 int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
841 struct slab_sheaf **sheafp, unsigned int size);
842
843 void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
844 struct slab_sheaf *sheaf);
845
846 void *kmem_cache_alloc_from_sheaf_noprof(struct kmem_cache *cachep, gfp_t gfp,
847 struct slab_sheaf *sheaf) __assume_slab_alignment __malloc;
848 #define kmem_cache_alloc_from_sheaf(...) \
849 alloc_hooks(kmem_cache_alloc_from_sheaf_noprof(__VA_ARGS__))
850
851 unsigned int kmem_cache_sheaf_size(struct slab_sheaf *sheaf);
852
853 /*
854 * These macros allow declaring a kmem_buckets * parameter alongside size, which
855 * can be compiled out with CONFIG_SLAB_BUCKETS=n so that a large number of call
856 * sites don't have to pass NULL.
857 */
858 #ifdef CONFIG_SLAB_BUCKETS
859 #define DECL_BUCKET_PARAMS(_size, _b) size_t (_size), kmem_buckets *(_b)
860 #define PASS_BUCKET_PARAMS(_size, _b) (_size), (_b)
861 #define PASS_BUCKET_PARAM(_b) (_b)
862 #else
863 #define DECL_BUCKET_PARAMS(_size, _b) size_t (_size)
864 #define PASS_BUCKET_PARAMS(_size, _b) (_size)
865 #define PASS_BUCKET_PARAM(_b) NULL
866 #endif
867
868 /*
869 * The following functions are not to be used directly and are intended only
870 * for internal use from kmalloc() and kmalloc_node()
871 * with the exception of kunit tests
872 */
873
874 void *__kmalloc_noprof(size_t size, gfp_t flags)
875 __assume_kmalloc_alignment __alloc_size(1);
876
877 void *__kmalloc_node_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node)
878 __assume_kmalloc_alignment __alloc_size(1);
879
880 void *__kmalloc_cache_noprof(struct kmem_cache *s, gfp_t flags, size_t size)
881 __assume_kmalloc_alignment __alloc_size(3);
882
883 void *__kmalloc_cache_node_noprof(struct kmem_cache *s, gfp_t gfpflags,
884 int node, size_t size)
885 __assume_kmalloc_alignment __alloc_size(4);
886
887 void *__kmalloc_large_noprof(size_t size, gfp_t flags)
888 __assume_page_alignment __alloc_size(1);
889
890 void *__kmalloc_large_node_noprof(size_t size, gfp_t flags, int node)
891 __assume_page_alignment __alloc_size(1);
892
893 /**
894 * kmalloc - allocate kernel memory
895 * @size: how many bytes of memory are required.
896 * @flags: describe the allocation context
897 *
898 * kmalloc is the normal method of allocating memory
899 * for objects smaller than page size in the kernel.
900 *
901 * The allocated object address is aligned to at least ARCH_KMALLOC_MINALIGN
902 * bytes. For @size of power of two bytes, the alignment is also guaranteed
903 * to be at least to the size. For other sizes, the alignment is guaranteed to
904 * be at least the largest power-of-two divisor of @size.
905 *
906 * The @flags argument may be one of the GFP flags defined at
907 * include/linux/gfp_types.h and described at
908 * :ref:`Documentation/core-api/mm-api.rst <mm-api-gfp-flags>`
909 *
910 * The recommended usage of the @flags is described at
911 * :ref:`Documentation/core-api/memory-allocation.rst <memory_allocation>`
912 *
913 * Below is a brief outline of the most useful GFP flags
914 *
915 * %GFP_KERNEL
916 * Allocate normal kernel ram. May sleep.
917 *
918 * %GFP_NOWAIT
919 * Allocation will not sleep.
920 *
921 * %GFP_ATOMIC
922 * Allocation will not sleep. May use emergency pools.
923 *
924 * Also it is possible to set different flags by OR'ing
925 * in one or more of the following additional @flags:
926 *
927 * %__GFP_ZERO
928 * Zero the allocated memory before returning. Also see kzalloc().
929 *
930 * %__GFP_HIGH
931 * This allocation has high priority and may use emergency pools.
932 *
933 * %__GFP_NOFAIL
934 * Indicate that this allocation is in no way allowed to fail
935 * (think twice before using).
936 *
937 * %__GFP_NORETRY
938 * If memory is not immediately available,
939 * then give up at once.
940 *
941 * %__GFP_NOWARN
942 * If allocation fails, don't issue any warnings.
943 *
944 * %__GFP_RETRY_MAYFAIL
945 * Try really hard to succeed the allocation but fail
946 * eventually.
947 */
kmalloc_noprof(size_t size,gfp_t flags)948 static __always_inline __alloc_size(1) void *kmalloc_noprof(size_t size, gfp_t flags)
949 {
950 if (__builtin_constant_p(size) && size) {
951 unsigned int index;
952
953 if (size > KMALLOC_MAX_CACHE_SIZE)
954 return __kmalloc_large_noprof(size, flags);
955
956 index = kmalloc_index(size);
957 return __kmalloc_cache_noprof(
958 kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index],
959 flags, size);
960 }
961 return __kmalloc_noprof(size, flags);
962 }
963 #define kmalloc(...) alloc_hooks(kmalloc_noprof(__VA_ARGS__))
964
965 void *kmalloc_nolock_noprof(size_t size, gfp_t gfp_flags, int node);
966 #define kmalloc_nolock(...) alloc_hooks(kmalloc_nolock_noprof(__VA_ARGS__))
967
968 #define kmem_buckets_alloc(_b, _size, _flags) \
969 alloc_hooks(__kmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE))
970
971 #define kmem_buckets_alloc_track_caller(_b, _size, _flags) \
972 alloc_hooks(__kmalloc_node_track_caller_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE, _RET_IP_))
973
kmalloc_node_noprof(size_t size,gfp_t flags,int node)974 static __always_inline __alloc_size(1) void *kmalloc_node_noprof(size_t size, gfp_t flags, int node)
975 {
976 if (__builtin_constant_p(size) && size) {
977 unsigned int index;
978
979 if (size > KMALLOC_MAX_CACHE_SIZE)
980 return __kmalloc_large_node_noprof(size, flags, node);
981
982 index = kmalloc_index(size);
983 return __kmalloc_cache_node_noprof(
984 kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index],
985 flags, node, size);
986 }
987 return __kmalloc_node_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node);
988 }
989 #define kmalloc_node(...) alloc_hooks(kmalloc_node_noprof(__VA_ARGS__))
990
991 /**
992 * kmalloc_array - allocate memory for an array.
993 * @n: number of elements.
994 * @size: element size.
995 * @flags: the type of memory to allocate (see kmalloc).
996 */
kmalloc_array_noprof(size_t n,size_t size,gfp_t flags)997 static inline __alloc_size(1, 2) void *kmalloc_array_noprof(size_t n, size_t size, gfp_t flags)
998 {
999 size_t bytes;
1000
1001 if (unlikely(check_mul_overflow(n, size, &bytes)))
1002 return NULL;
1003 return kmalloc_noprof(bytes, flags);
1004 }
1005 #define kmalloc_array(...) alloc_hooks(kmalloc_array_noprof(__VA_ARGS__))
1006
1007 /**
1008 * krealloc_array - reallocate memory for an array.
1009 * @p: pointer to the memory chunk to reallocate
1010 * @new_n: new number of elements to alloc
1011 * @new_size: new size of a single member of the array
1012 * @flags: the type of memory to allocate (see kmalloc)
1013 *
1014 * If __GFP_ZERO logic is requested, callers must ensure that, starting with the
1015 * initial memory allocation, every subsequent call to this API for the same
1016 * memory allocation is flagged with __GFP_ZERO. Otherwise, it is possible that
1017 * __GFP_ZERO is not fully honored by this API.
1018 *
1019 * See krealloc_noprof() for further details.
1020 *
1021 * In any case, the contents of the object pointed to are preserved up to the
1022 * lesser of the new and old sizes.
1023 */
krealloc_array_noprof(void * p,size_t new_n,size_t new_size,gfp_t flags)1024 static inline __realloc_size(2, 3) void * __must_check krealloc_array_noprof(void *p,
1025 size_t new_n,
1026 size_t new_size,
1027 gfp_t flags)
1028 {
1029 size_t bytes;
1030
1031 if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
1032 return NULL;
1033
1034 return krealloc_noprof(p, bytes, flags);
1035 }
1036 #define krealloc_array(...) alloc_hooks(krealloc_array_noprof(__VA_ARGS__))
1037
1038 /**
1039 * kcalloc - allocate memory for an array. The memory is set to zero.
1040 * @n: number of elements.
1041 * @size: element size.
1042 * @flags: the type of memory to allocate (see kmalloc).
1043 */
1044 #define kcalloc(n, size, flags) kmalloc_array(n, size, (flags) | __GFP_ZERO)
1045
1046 void *__kmalloc_node_track_caller_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node,
1047 unsigned long caller) __alloc_size(1);
1048 #define kmalloc_node_track_caller_noprof(size, flags, node, caller) \
1049 __kmalloc_node_track_caller_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node, caller)
1050 #define kmalloc_node_track_caller(...) \
1051 alloc_hooks(kmalloc_node_track_caller_noprof(__VA_ARGS__, _RET_IP_))
1052
1053 /*
1054 * kmalloc_track_caller is a special version of kmalloc that records the
1055 * calling function of the routine calling it for slab leak tracking instead
1056 * of just the calling function (confusing, eh?).
1057 * It's useful when the call to kmalloc comes from a widely-used standard
1058 * allocator where we care about the real place the memory allocation
1059 * request comes from.
1060 */
1061 #define kmalloc_track_caller(...) kmalloc_node_track_caller(__VA_ARGS__, NUMA_NO_NODE)
1062
1063 #define kmalloc_track_caller_noprof(...) \
1064 kmalloc_node_track_caller_noprof(__VA_ARGS__, NUMA_NO_NODE, _RET_IP_)
1065
kmalloc_array_node_noprof(size_t n,size_t size,gfp_t flags,int node)1066 static inline __alloc_size(1, 2) void *kmalloc_array_node_noprof(size_t n, size_t size, gfp_t flags,
1067 int node)
1068 {
1069 size_t bytes;
1070
1071 if (unlikely(check_mul_overflow(n, size, &bytes)))
1072 return NULL;
1073 if (__builtin_constant_p(n) && __builtin_constant_p(size))
1074 return kmalloc_node_noprof(bytes, flags, node);
1075 return __kmalloc_node_noprof(PASS_BUCKET_PARAMS(bytes, NULL), flags, node);
1076 }
1077 #define kmalloc_array_node(...) alloc_hooks(kmalloc_array_node_noprof(__VA_ARGS__))
1078
1079 #define kcalloc_node(_n, _size, _flags, _node) \
1080 kmalloc_array_node(_n, _size, (_flags) | __GFP_ZERO, _node)
1081
1082 /*
1083 * Shortcuts
1084 */
1085 #define kmem_cache_zalloc(_k, _flags) kmem_cache_alloc(_k, (_flags)|__GFP_ZERO)
1086
1087 /**
1088 * kzalloc - allocate memory. The memory is set to zero.
1089 * @size: how many bytes of memory are required.
1090 * @flags: the type of memory to allocate (see kmalloc).
1091 */
kzalloc_noprof(size_t size,gfp_t flags)1092 static inline __alloc_size(1) void *kzalloc_noprof(size_t size, gfp_t flags)
1093 {
1094 return kmalloc_noprof(size, flags | __GFP_ZERO);
1095 }
1096 #define kzalloc(...) alloc_hooks(kzalloc_noprof(__VA_ARGS__))
1097 #define kzalloc_node(_size, _flags, _node) kmalloc_node(_size, (_flags)|__GFP_ZERO, _node)
1098
1099 void *__kvmalloc_node_noprof(DECL_BUCKET_PARAMS(size, b), unsigned long align,
1100 gfp_t flags, int node) __alloc_size(1);
1101 #define kvmalloc_node_align_noprof(_size, _align, _flags, _node) \
1102 __kvmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, NULL), _align, _flags, _node)
1103 #define kvmalloc_node_align(...) \
1104 alloc_hooks(kvmalloc_node_align_noprof(__VA_ARGS__))
1105 #define kvmalloc_node(_s, _f, _n) kvmalloc_node_align(_s, 1, _f, _n)
1106 #define kvmalloc(...) kvmalloc_node(__VA_ARGS__, NUMA_NO_NODE)
1107 #define kvzalloc(_size, _flags) kvmalloc(_size, (_flags)|__GFP_ZERO)
1108
1109 #define kvzalloc_node(_size, _flags, _node) kvmalloc_node(_size, (_flags)|__GFP_ZERO, _node)
1110
1111 #define kmem_buckets_valloc(_b, _size, _flags) \
1112 alloc_hooks(__kvmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), 1, _flags, NUMA_NO_NODE))
1113
1114 static inline __alloc_size(1, 2) void *
kvmalloc_array_node_noprof(size_t n,size_t size,gfp_t flags,int node)1115 kvmalloc_array_node_noprof(size_t n, size_t size, gfp_t flags, int node)
1116 {
1117 size_t bytes;
1118
1119 if (unlikely(check_mul_overflow(n, size, &bytes)))
1120 return NULL;
1121
1122 return kvmalloc_node_align_noprof(bytes, 1, flags, node);
1123 }
1124
1125 #define kvmalloc_array_noprof(...) kvmalloc_array_node_noprof(__VA_ARGS__, NUMA_NO_NODE)
1126 #define kvcalloc_node_noprof(_n,_s,_f,_node) kvmalloc_array_node_noprof(_n,_s,(_f)|__GFP_ZERO,_node)
1127 #define kvcalloc_noprof(...) kvcalloc_node_noprof(__VA_ARGS__, NUMA_NO_NODE)
1128
1129 #define kvmalloc_array(...) alloc_hooks(kvmalloc_array_noprof(__VA_ARGS__))
1130 #define kvcalloc_node(...) alloc_hooks(kvcalloc_node_noprof(__VA_ARGS__))
1131 #define kvcalloc(...) alloc_hooks(kvcalloc_noprof(__VA_ARGS__))
1132
1133 void *kvrealloc_node_align_noprof(const void *p, size_t size, unsigned long align,
1134 gfp_t flags, int nid) __realloc_size(2);
1135 #define kvrealloc_node_align(...) \
1136 alloc_hooks(kvrealloc_node_align_noprof(__VA_ARGS__))
1137 #define kvrealloc_node(_p, _s, _f, _n) kvrealloc_node_align(_p, _s, 1, _f, _n)
1138 #define kvrealloc(...) kvrealloc_node(__VA_ARGS__, NUMA_NO_NODE)
1139
1140 extern void kvfree(const void *addr);
1141 DEFINE_FREE(kvfree, void *, if (!IS_ERR_OR_NULL(_T)) kvfree(_T))
1142
1143 extern void kvfree_sensitive(const void *addr, size_t len);
1144
1145 unsigned int kmem_cache_size(struct kmem_cache *s);
1146
1147 #ifndef CONFIG_KVFREE_RCU_BATCHED
kvfree_rcu_barrier(void)1148 static inline void kvfree_rcu_barrier(void)
1149 {
1150 rcu_barrier();
1151 }
1152
kfree_rcu_scheduler_running(void)1153 static inline void kfree_rcu_scheduler_running(void) { }
1154 #else
1155 void kvfree_rcu_barrier(void);
1156
1157 void kfree_rcu_scheduler_running(void);
1158 #endif
1159
1160 /**
1161 * kmalloc_size_roundup - Report allocation bucket size for the given size
1162 *
1163 * @size: Number of bytes to round up from.
1164 *
1165 * This returns the number of bytes that would be available in a kmalloc()
1166 * allocation of @size bytes. For example, a 126 byte request would be
1167 * rounded up to the next sized kmalloc bucket, 128 bytes. (This is strictly
1168 * for the general-purpose kmalloc()-based allocations, and is not for the
1169 * pre-sized kmem_cache_alloc()-based allocations.)
1170 *
1171 * Use this to kmalloc() the full bucket size ahead of time instead of using
1172 * ksize() to query the size after an allocation.
1173 */
1174 size_t kmalloc_size_roundup(size_t size);
1175
1176 void __init kmem_cache_init_late(void);
1177 void __init kvfree_rcu_init(void);
1178
1179 #endif /* _LINUX_SLAB_H */
1180