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|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
*
* (C) SGI 2006, Christoph Lameter
* Cleaned up and restructured to ease the addition of alternative
* implementations of SLAB allocators.
* (C) Linux Foundation 2008-2013
* Unified interface for all slab allocators
*/
#ifndef _LINUX_SLAB_H
#define _LINUX_SLAB_H
#include <linux/cache.h>
#include <linux/gfp.h>
#include <linux/overflow.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/percpu-refcount.h>
#include <linux/cleanup.h>
#include <linux/hash.h>
enum _slab_flag_bits {
_SLAB_CONSISTENCY_CHECKS,
_SLAB_RED_ZONE,
_SLAB_POISON,
_SLAB_KMALLOC,
_SLAB_HWCACHE_ALIGN,
_SLAB_CACHE_DMA,
_SLAB_CACHE_DMA32,
_SLAB_STORE_USER,
_SLAB_PANIC,
_SLAB_TYPESAFE_BY_RCU,
_SLAB_TRACE,
#ifdef CONFIG_DEBUG_OBJECTS
_SLAB_DEBUG_OBJECTS,
#endif
_SLAB_NOLEAKTRACE,
_SLAB_NO_MERGE,
#ifdef CONFIG_FAILSLAB
_SLAB_FAILSLAB,
#endif
#ifdef CONFIG_MEMCG_KMEM
_SLAB_ACCOUNT,
#endif
#ifdef CONFIG_KASAN_GENERIC
_SLAB_KASAN,
#endif
_SLAB_NO_USER_FLAGS,
#ifdef CONFIG_KFENCE
_SLAB_SKIP_KFENCE,
#endif
#ifndef CONFIG_SLUB_TINY
_SLAB_RECLAIM_ACCOUNT,
#endif
_SLAB_OBJECT_POISON,
_SLAB_CMPXCHG_DOUBLE,
#ifdef CONFIG_SLAB_OBJ_EXT
_SLAB_NO_OBJ_EXT,
#endif
_SLAB_FLAGS_LAST_BIT
};
#define __SLAB_FLAG_BIT(nr) ((slab_flags_t __force)(1U << (nr)))
#define __SLAB_FLAG_UNUSED ((slab_flags_t __force)(0U))
/*
* Flags to pass to kmem_cache_create().
* The ones marked DEBUG need CONFIG_SLUB_DEBUG enabled, otherwise are no-op
*/
/* DEBUG: Perform (expensive) checks on alloc/free */
#define SLAB_CONSISTENCY_CHECKS __SLAB_FLAG_BIT(_SLAB_CONSISTENCY_CHECKS)
/* DEBUG: Red zone objs in a cache */
#define SLAB_RED_ZONE __SLAB_FLAG_BIT(_SLAB_RED_ZONE)
/* DEBUG: Poison objects */
#define SLAB_POISON __SLAB_FLAG_BIT(_SLAB_POISON)
/* Indicate a kmalloc slab */
#define SLAB_KMALLOC __SLAB_FLAG_BIT(_SLAB_KMALLOC)
/* Align objs on cache lines */
#define SLAB_HWCACHE_ALIGN __SLAB_FLAG_BIT(_SLAB_HWCACHE_ALIGN)
/* Use GFP_DMA memory */
#define SLAB_CACHE_DMA __SLAB_FLAG_BIT(_SLAB_CACHE_DMA)
/* Use GFP_DMA32 memory */
#define SLAB_CACHE_DMA32 __SLAB_FLAG_BIT(_SLAB_CACHE_DMA32)
/* DEBUG: Store the last owner for bug hunting */
#define SLAB_STORE_USER __SLAB_FLAG_BIT(_SLAB_STORE_USER)
/* Panic if kmem_cache_create() fails */
#define SLAB_PANIC __SLAB_FLAG_BIT(_SLAB_PANIC)
/*
* SLAB_TYPESAFE_BY_RCU - **WARNING** READ THIS!
*
* This delays freeing the SLAB page by a grace period, it does _NOT_
* delay object freeing. This means that if you do kmem_cache_free()
* that memory location is free to be reused at any time. Thus it may
* be possible to see another object there in the same RCU grace period.
*
* This feature only ensures the memory location backing the object
* stays valid, the trick to using this is relying on an independent
* object validation pass. Something like:
*
* begin:
* rcu_read_lock();
* obj = lockless_lookup(key);
* if (obj) {
* if (!try_get_ref(obj)) // might fail for free objects
* rcu_read_unlock();
* goto begin;
*
* if (obj->key != key) { // not the object we expected
* put_ref(obj);
* rcu_read_unlock();
* goto begin;
* }
* }
* rcu_read_unlock();
*
* This is useful if we need to approach a kernel structure obliquely,
* from its address obtained without the usual locking. We can lock
* the structure to stabilize it and check it's still at the given address,
* only if we can be sure that the memory has not been meanwhile reused
* for some other kind of object (which our subsystem's lock might corrupt).
*
* rcu_read_lock before reading the address, then rcu_read_unlock after
* taking the spinlock within the structure expected at that address.
*
* Note that it is not possible to acquire a lock within a structure
* allocated with SLAB_TYPESAFE_BY_RCU without first acquiring a reference
* as described above. The reason is that SLAB_TYPESAFE_BY_RCU pages
* are not zeroed before being given to the slab, which means that any
* locks must be initialized after each and every kmem_struct_alloc().
* Alternatively, make the ctor passed to kmem_cache_create() initialize
* the locks at page-allocation time, as is done in __i915_request_ctor(),
* sighand_ctor(), and anon_vma_ctor(). Such a ctor permits readers
* to safely acquire those ctor-initialized locks under rcu_read_lock()
* protection.
*
* Note that SLAB_TYPESAFE_BY_RCU was originally named SLAB_DESTROY_BY_RCU.
*/
/* Defer freeing slabs to RCU */
#define SLAB_TYPESAFE_BY_RCU __SLAB_FLAG_BIT(_SLAB_TYPESAFE_BY_RCU)
/* Trace allocations and frees */
#define SLAB_TRACE __SLAB_FLAG_BIT(_SLAB_TRACE)
/* Flag to prevent checks on free */
#ifdef CONFIG_DEBUG_OBJECTS
# define SLAB_DEBUG_OBJECTS __SLAB_FLAG_BIT(_SLAB_DEBUG_OBJECTS)
#else
# define SLAB_DEBUG_OBJECTS __SLAB_FLAG_UNUSED
#endif
/* Avoid kmemleak tracing */
#define SLAB_NOLEAKTRACE __SLAB_FLAG_BIT(_SLAB_NOLEAKTRACE)
/*
* Prevent merging with compatible kmem caches. This flag should be used
* cautiously. Valid use cases:
*
* - caches created for self-tests (e.g. kunit)
* - general caches created and used by a subsystem, only when a
* (subsystem-specific) debug option is enabled
* - performance critical caches, should be very rare and consulted with slab
* maintainers, and not used together with CONFIG_SLUB_TINY
*/
#define SLAB_NO_MERGE __SLAB_FLAG_BIT(_SLAB_NO_MERGE)
/* Fault injection mark */
#ifdef CONFIG_FAILSLAB
# define SLAB_FAILSLAB __SLAB_FLAG_BIT(_SLAB_FAILSLAB)
#else
# define SLAB_FAILSLAB __SLAB_FLAG_UNUSED
#endif
/* Account to memcg */
#ifdef CONFIG_MEMCG_KMEM
# define SLAB_ACCOUNT __SLAB_FLAG_BIT(_SLAB_ACCOUNT)
#else
# define SLAB_ACCOUNT __SLAB_FLAG_UNUSED
#endif
#ifdef CONFIG_KASAN_GENERIC
#define SLAB_KASAN __SLAB_FLAG_BIT(_SLAB_KASAN)
#else
#define SLAB_KASAN __SLAB_FLAG_UNUSED
#endif
/*
* Ignore user specified debugging flags.
* Intended for caches created for self-tests so they have only flags
* specified in the code and other flags are ignored.
*/
#define SLAB_NO_USER_FLAGS __SLAB_FLAG_BIT(_SLAB_NO_USER_FLAGS)
#ifdef CONFIG_KFENCE
#define SLAB_SKIP_KFENCE __SLAB_FLAG_BIT(_SLAB_SKIP_KFENCE)
#else
#define SLAB_SKIP_KFENCE __SLAB_FLAG_UNUSED
#endif
/* The following flags affect the page allocator grouping pages by mobility */
/* Objects are reclaimable */
#ifndef CONFIG_SLUB_TINY
#define SLAB_RECLAIM_ACCOUNT __SLAB_FLAG_BIT(_SLAB_RECLAIM_ACCOUNT)
#else
#define SLAB_RECLAIM_ACCOUNT __SLAB_FLAG_UNUSED
#endif
#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
/* Slab created using create_boot_cache */
#ifdef CONFIG_SLAB_OBJ_EXT
#define SLAB_NO_OBJ_EXT __SLAB_FLAG_BIT(_SLAB_NO_OBJ_EXT)
#else
#define SLAB_NO_OBJ_EXT __SLAB_FLAG_UNUSED
#endif
/*
* ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
*
* Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
*
* ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
* Both make kfree a no-op.
*/
#define ZERO_SIZE_PTR ((void *)16)
#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
(unsigned long)ZERO_SIZE_PTR)
#include <linux/kasan.h>
struct list_lru;
struct mem_cgroup;
/*
* struct kmem_cache related prototypes
*/
bool slab_is_available(void);
struct kmem_cache *kmem_cache_create(const char *name, unsigned int size,
unsigned int align, slab_flags_t flags,
void (*ctor)(void *));
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 *));
void kmem_cache_destroy(struct kmem_cache *s);
int kmem_cache_shrink(struct kmem_cache *s);
/*
* Please use this macro to create slab caches. Simply specify the
* name of the structure and maybe some flags that are listed above.
*
* The alignment of the struct determines object alignment. If you
* f.e. add ____cacheline_aligned_in_smp to the struct declaration
* then the objects will be properly aligned in SMP configurations.
*/
#define KMEM_CACHE(__struct, __flags) \
kmem_cache_create(#__struct, sizeof(struct __struct), \
__alignof__(struct __struct), (__flags), NULL)
/*
* To whitelist a single field for copying to/from usercopy, use this
* macro instead for KMEM_CACHE() above.
*/
#define KMEM_CACHE_USERCOPY(__struct, __flags, __field) \
kmem_cache_create_usercopy(#__struct, \
sizeof(struct __struct), \
__alignof__(struct __struct), (__flags), \
offsetof(struct __struct, __field), \
sizeof_field(struct __struct, __field), NULL)
/*
* Common kmalloc functions provided by all allocators
*/
void * __must_check krealloc_noprof(const void *objp, size_t new_size,
gfp_t flags) __realloc_size(2);
#define krealloc(...) alloc_hooks(krealloc_noprof(__VA_ARGS__))
void kfree(const void *objp);
void kfree_sensitive(const void *objp);
size_t __ksize(const void *objp);
DEFINE_FREE(kfree, void *, if (!IS_ERR_OR_NULL(_T)) kfree(_T))
/**
* ksize - Report actual allocation size of associated object
*
* @objp: Pointer returned from a prior kmalloc()-family allocation.
*
* This should not be used for writing beyond the originally requested
* allocation size. Either use krealloc() or round up the allocation size
* with kmalloc_size_roundup() prior to allocation. If this is used to
* access beyond the originally requested allocation size, UBSAN_BOUNDS
* and/or FORTIFY_SOURCE may trip, since they only know about the
* originally allocated size via the __alloc_size attribute.
*/
size_t ksize(const void *objp);
#ifdef CONFIG_PRINTK
bool kmem_dump_obj(void *object);
#else
static inline bool kmem_dump_obj(void *object) { return false; }
#endif
/*
* Some archs want to perform DMA into kmalloc caches and need a guaranteed
* alignment larger than the alignment of a 64-bit integer.
* Setting ARCH_DMA_MINALIGN in arch headers allows that.
*/
#ifdef ARCH_HAS_DMA_MINALIGN
#if ARCH_DMA_MINALIGN > 8 && !defined(ARCH_KMALLOC_MINALIGN)
#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
#endif
#endif
#ifndef ARCH_KMALLOC_MINALIGN
#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
#elif ARCH_KMALLOC_MINALIGN > 8
#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
#endif
/*
* Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
* Intended for arches that get misalignment faults even for 64 bit integer
* aligned buffers.
*/
#ifndef ARCH_SLAB_MINALIGN
#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
#endif
/*
* Arches can define this function if they want to decide the minimum slab
* alignment at runtime. The value returned by the function must be a power
* of two and >= ARCH_SLAB_MINALIGN.
*/
#ifndef arch_slab_minalign
static inline unsigned int arch_slab_minalign(void)
{
return ARCH_SLAB_MINALIGN;
}
#endif
/*
* kmem_cache_alloc and friends return pointers aligned to ARCH_SLAB_MINALIGN.
* kmalloc and friends return pointers aligned to both ARCH_KMALLOC_MINALIGN
* and ARCH_SLAB_MINALIGN, but here we only assume the former alignment.
*/
#define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
#define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
#define __assume_page_alignment __assume_aligned(PAGE_SIZE)
/*
* Kmalloc array related definitions
*/
/*
* SLUB directly allocates requests fitting in to an order-1 page
* (PAGE_SIZE*2). Larger requests are passed to the page allocator.
*/
#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
#define KMALLOC_SHIFT_MAX (MAX_PAGE_ORDER + PAGE_SHIFT)
#ifndef KMALLOC_SHIFT_LOW
#define KMALLOC_SHIFT_LOW 3
#endif
/* Maximum allocatable size */
#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
/* Maximum size for which we actually use a slab cache */
#define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
/* Maximum order allocatable via the slab allocator */
#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
/*
* Kmalloc subsystem.
*/
#ifndef KMALLOC_MIN_SIZE
#define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
#endif
/*
* This restriction comes from byte sized index implementation.
* Page size is normally 2^12 bytes and, in this case, if we want to use
* byte sized index which can represent 2^8 entries, the size of the object
* should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
* If minimum size of kmalloc is less than 16, we use it as minimum object
* size and give up to use byte sized index.
*/
#define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
(KMALLOC_MIN_SIZE) : 16)
#ifdef CONFIG_RANDOM_KMALLOC_CACHES
#define RANDOM_KMALLOC_CACHES_NR 15 // # of cache copies
#else
#define RANDOM_KMALLOC_CACHES_NR 0
#endif
/*
* Whenever changing this, take care of that kmalloc_type() and
* create_kmalloc_caches() still work as intended.
*
* KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP
* is for accounted but unreclaimable and non-dma objects. All the other
* kmem caches can have both accounted and unaccounted objects.
*/
enum kmalloc_cache_type {
KMALLOC_NORMAL = 0,
#ifndef CONFIG_ZONE_DMA
KMALLOC_DMA = KMALLOC_NORMAL,
#endif
#ifndef CONFIG_MEMCG_KMEM
KMALLOC_CGROUP = KMALLOC_NORMAL,
#endif
KMALLOC_RANDOM_START = KMALLOC_NORMAL,
KMALLOC_RANDOM_END = KMALLOC_RANDOM_START + RANDOM_KMALLOC_CACHES_NR,
#ifdef CONFIG_SLUB_TINY
KMALLOC_RECLAIM = KMALLOC_NORMAL,
#else
KMALLOC_RECLAIM,
#endif
#ifdef CONFIG_ZONE_DMA
KMALLOC_DMA,
#endif
#ifdef CONFIG_MEMCG_KMEM
KMALLOC_CGROUP,
#endif
NR_KMALLOC_TYPES
};
typedef struct kmem_cache * kmem_buckets[KMALLOC_SHIFT_HIGH + 1];
extern kmem_buckets kmalloc_caches[NR_KMALLOC_TYPES];
/*
* Define gfp bits that should not be set for KMALLOC_NORMAL.
*/
#define KMALLOC_NOT_NORMAL_BITS \
(__GFP_RECLAIMABLE | \
(IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \
(IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0))
extern unsigned long random_kmalloc_seed;
static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags, unsigned long caller)
{
/*
* The most common case is KMALLOC_NORMAL, so test for it
* with a single branch for all the relevant flags.
*/
if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0))
#ifdef CONFIG_RANDOM_KMALLOC_CACHES
/* RANDOM_KMALLOC_CACHES_NR (=15) copies + the KMALLOC_NORMAL */
return KMALLOC_RANDOM_START + hash_64(caller ^ random_kmalloc_seed,
ilog2(RANDOM_KMALLOC_CACHES_NR + 1));
#else
return KMALLOC_NORMAL;
#endif
/*
* At least one of the flags has to be set. Their priorities in
* decreasing order are:
* 1) __GFP_DMA
* 2) __GFP_RECLAIMABLE
* 3) __GFP_ACCOUNT
*/
if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA))
return KMALLOC_DMA;
if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE))
return KMALLOC_RECLAIM;
else
return KMALLOC_CGROUP;
}
/*
* Figure out which kmalloc slab an allocation of a certain size
* belongs to.
* 0 = zero alloc
* 1 = 65 .. 96 bytes
* 2 = 129 .. 192 bytes
* n = 2^(n-1)+1 .. 2^n
*
* Note: __kmalloc_index() is compile-time optimized, and not runtime optimized;
* typical usage is via kmalloc_index() and therefore evaluated at compile-time.
* Callers where !size_is_constant should only be test modules, where runtime
* overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab().
*/
static __always_inline unsigned int __kmalloc_index(size_t size,
bool size_is_constant)
{
if (!size)
return 0;
if (size <= KMALLOC_MIN_SIZE)
return KMALLOC_SHIFT_LOW;
if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
return 1;
if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
return 2;
if (size <= 8) return 3;
if (size <= 16) return 4;
if (size <= 32) return 5;
if (size <= 64) return 6;
if (size <= 128) return 7;
if (size <= 256) return 8;
if (size <= 512) return 9;
if (size <= 1024) return 10;
if (size <= 2 * 1024) return 11;
if (size <= 4 * 1024) return 12;
if (size <= 8 * 1024) return 13;
if (size <= 16 * 1024) return 14;
if (size <= 32 * 1024) return 15;
if (size <= 64 * 1024) return 16;
if (size <= 128 * 1024) return 17;
if (size <= 256 * 1024) return 18;
if (size <= 512 * 1024) return 19;
if (size <= 1024 * 1024) return 20;
if (size <= 2 * 1024 * 1024) return 21;
if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant)
BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()");
else
BUG();
/* Will never be reached. Needed because the compiler may complain */
return -1;
}
static_assert(PAGE_SHIFT <= 20);
#define kmalloc_index(s) __kmalloc_index(s, true)
#include <linux/alloc_tag.h>
/**
* kmem_cache_alloc - Allocate an object
* @cachep: The cache to allocate from.
* @flags: See kmalloc().
*
* Allocate an object from this cache.
* See kmem_cache_zalloc() for a shortcut of adding __GFP_ZERO to flags.
*
* Return: pointer to the new object or %NULL in case of error
*/
void *kmem_cache_alloc_noprof(struct kmem_cache *cachep,
gfp_t flags) __assume_slab_alignment __malloc;
#define kmem_cache_alloc(...) alloc_hooks(kmem_cache_alloc_noprof(__VA_ARGS__))
void *kmem_cache_alloc_lru_noprof(struct kmem_cache *s, struct list_lru *lru,
gfp_t gfpflags) __assume_slab_alignment __malloc;
#define kmem_cache_alloc_lru(...) alloc_hooks(kmem_cache_alloc_lru_noprof(__VA_ARGS__))
void kmem_cache_free(struct kmem_cache *s, void *objp);
kmem_buckets *kmem_buckets_create(const char *name, slab_flags_t flags,
unsigned int useroffset, unsigned int usersize,
void (*ctor)(void *));
/*
* Bulk allocation and freeing operations. These are accelerated in an
* allocator specific way to avoid taking locks repeatedly or building
* metadata structures unnecessarily.
*
* Note that interrupts must be enabled when calling these functions.
*/
void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p);
int kmem_cache_alloc_bulk_noprof(struct kmem_cache *s, gfp_t flags, size_t size, void **p);
#define kmem_cache_alloc_bulk(...) alloc_hooks(kmem_cache_alloc_bulk_noprof(__VA_ARGS__))
static __always_inline void kfree_bulk(size_t size, void **p)
{
kmem_cache_free_bulk(NULL, size, p);
}
void *kmem_cache_alloc_node_noprof(struct kmem_cache *s, gfp_t flags,
int node) __assume_slab_alignment __malloc;
#define kmem_cache_alloc_node(...) alloc_hooks(kmem_cache_alloc_node_noprof(__VA_ARGS__))
/*
* These macros allow declaring a kmem_buckets * parameter alongside size, which
* can be compiled out with CONFIG_SLAB_BUCKETS=n so that a large number of call
* sites don't have to pass NULL.
*/
#ifdef CONFIG_SLAB_BUCKETS
#define DECL_BUCKET_PARAMS(_size, _b) size_t (_size), kmem_buckets *(_b)
#define PASS_BUCKET_PARAMS(_size, _b) (_size), (_b)
#define PASS_BUCKET_PARAM(_b) (_b)
#else
#define DECL_BUCKET_PARAMS(_size, _b) size_t (_size)
#define PASS_BUCKET_PARAMS(_size, _b) (_size)
#define PASS_BUCKET_PARAM(_b) NULL
#endif
/*
* The following functions are not to be used directly and are intended only
* for internal use from kmalloc() and kmalloc_node()
* with the exception of kunit tests
*/
void *__kmalloc_noprof(size_t size, gfp_t flags)
__assume_kmalloc_alignment __alloc_size(1);
void *__kmalloc_node_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node)
__assume_kmalloc_alignment __alloc_size(1);
void *__kmalloc_cache_noprof(struct kmem_cache *s, gfp_t flags, size_t size)
__assume_kmalloc_alignment __alloc_size(3);
void *__kmalloc_cache_node_noprof(struct kmem_cache *s, gfp_t gfpflags,
int node, size_t size)
__assume_kmalloc_alignment __alloc_size(4);
void *__kmalloc_large_noprof(size_t size, gfp_t flags)
__assume_page_alignment __alloc_size(1);
void *__kmalloc_large_node_noprof(size_t size, gfp_t flags, int node)
__assume_page_alignment __alloc_size(1);
/**
* kmalloc - allocate kernel memory
* @size: how many bytes of memory are required.
* @flags: describe the allocation context
*
* kmalloc is the normal method of allocating memory
* for objects smaller than page size in the kernel.
*
* The allocated object address is aligned to at least ARCH_KMALLOC_MINALIGN
* bytes. For @size of power of two bytes, the alignment is also guaranteed
* to be at least to the size. For other sizes, the alignment is guaranteed to
* be at least the largest power-of-two divisor of @size.
*
* The @flags argument may be one of the GFP flags defined at
* include/linux/gfp_types.h and described at
* :ref:`Documentation/core-api/mm-api.rst <mm-api-gfp-flags>`
*
* The recommended usage of the @flags is described at
* :ref:`Documentation/core-api/memory-allocation.rst <memory_allocation>`
*
* Below is a brief outline of the most useful GFP flags
*
* %GFP_KERNEL
* Allocate normal kernel ram. May sleep.
*
* %GFP_NOWAIT
* Allocation will not sleep.
*
* %GFP_ATOMIC
* Allocation will not sleep. May use emergency pools.
*
* Also it is possible to set different flags by OR'ing
* in one or more of the following additional @flags:
*
* %__GFP_ZERO
* Zero the allocated memory before returning. Also see kzalloc().
*
* %__GFP_HIGH
* This allocation has high priority and may use emergency pools.
*
* %__GFP_NOFAIL
* Indicate that this allocation is in no way allowed to fail
* (think twice before using).
*
* %__GFP_NORETRY
* If memory is not immediately available,
* then give up at once.
*
* %__GFP_NOWARN
* If allocation fails, don't issue any warnings.
*
* %__GFP_RETRY_MAYFAIL
* Try really hard to succeed the allocation but fail
* eventually.
*/
static __always_inline __alloc_size(1) void *kmalloc_noprof(size_t size, gfp_t flags)
{
if (__builtin_constant_p(size) && size) {
unsigned int index;
if (size > KMALLOC_MAX_CACHE_SIZE)
return __kmalloc_large_noprof(size, flags);
index = kmalloc_index(size);
return __kmalloc_cache_noprof(
kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index],
flags, size);
}
return __kmalloc_noprof(size, flags);
}
#define kmalloc(...) alloc_hooks(kmalloc_noprof(__VA_ARGS__))
#define kmem_buckets_alloc(_b, _size, _flags) \
alloc_hooks(__kmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE))
#define kmem_buckets_alloc_track_caller(_b, _size, _flags) \
alloc_hooks(__kmalloc_node_track_caller_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE, _RET_IP_))
static __always_inline __alloc_size(1) void *kmalloc_node_noprof(size_t size, gfp_t flags, int node)
{
if (__builtin_constant_p(size) && size) {
unsigned int index;
if (size > KMALLOC_MAX_CACHE_SIZE)
return __kmalloc_large_node_noprof(size, flags, node);
index = kmalloc_index(size);
return __kmalloc_cache_node_noprof(
kmalloc_caches[kmalloc_type(flags, _RET_IP_)][index],
flags, node, size);
}
return __kmalloc_node_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node);
}
#define kmalloc_node(...) alloc_hooks(kmalloc_node_noprof(__VA_ARGS__))
/**
* kmalloc_array - allocate memory for an array.
* @n: number of elements.
* @size: element size.
* @flags: the type of memory to allocate (see kmalloc).
*/
static inline __alloc_size(1, 2) void *kmalloc_array_noprof(size_t n, size_t size, gfp_t flags)
{
size_t bytes;
if (unlikely(check_mul_overflow(n, size, &bytes)))
return NULL;
if (__builtin_constant_p(n) && __builtin_constant_p(size))
return kmalloc_noprof(bytes, flags);
return kmalloc_noprof(bytes, flags);
}
#define kmalloc_array(...) alloc_hooks(kmalloc_array_noprof(__VA_ARGS__))
/**
* krealloc_array - reallocate memory for an array.
* @p: pointer to the memory chunk to reallocate
* @new_n: new number of elements to alloc
* @new_size: new size of a single member of the array
* @flags: the type of memory to allocate (see kmalloc)
*/
static inline __realloc_size(2, 3) void * __must_check krealloc_array_noprof(void *p,
size_t new_n,
size_t new_size,
gfp_t flags)
{
size_t bytes;
if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
return NULL;
return krealloc_noprof(p, bytes, flags);
}
#define krealloc_array(...) alloc_hooks(krealloc_array_noprof(__VA_ARGS__))
/**
* kcalloc - allocate memory for an array. The memory is set to zero.
* @n: number of elements.
* @size: element size.
* @flags: the type of memory to allocate (see kmalloc).
*/
#define kcalloc(n, size, flags) kmalloc_array(n, size, (flags) | __GFP_ZERO)
void *__kmalloc_node_track_caller_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node,
unsigned long caller) __alloc_size(1);
#define kmalloc_node_track_caller_noprof(size, flags, node, caller) \
__kmalloc_node_track_caller_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node, caller)
#define kmalloc_node_track_caller(...) \
alloc_hooks(kmalloc_node_track_caller_noprof(__VA_ARGS__, _RET_IP_))
/*
* kmalloc_track_caller is a special version of kmalloc that records the
* calling function of the routine calling it for slab leak tracking instead
* of just the calling function (confusing, eh?).
* It's useful when the call to kmalloc comes from a widely-used standard
* allocator where we care about the real place the memory allocation
* request comes from.
*/
#define kmalloc_track_caller(...) kmalloc_node_track_caller(__VA_ARGS__, NUMA_NO_NODE)
#define kmalloc_track_caller_noprof(...) \
kmalloc_node_track_caller_noprof(__VA_ARGS__, NUMA_NO_NODE, _RET_IP_)
static inline __alloc_size(1, 2) void *kmalloc_array_node_noprof(size_t n, size_t size, gfp_t flags,
int node)
{
size_t bytes;
if (unlikely(check_mul_overflow(n, size, &bytes)))
return NULL;
if (__builtin_constant_p(n) && __builtin_constant_p(size))
return kmalloc_node_noprof(bytes, flags, node);
return __kmalloc_node_noprof(PASS_BUCKET_PARAMS(bytes, NULL), flags, node);
}
#define kmalloc_array_node(...) alloc_hooks(kmalloc_array_node_noprof(__VA_ARGS__))
#define kcalloc_node(_n, _size, _flags, _node) \
kmalloc_array_node(_n, _size, (_flags) | __GFP_ZERO, _node)
/*
* Shortcuts
*/
#define kmem_cache_zalloc(_k, _flags) kmem_cache_alloc(_k, (_flags)|__GFP_ZERO)
/**
* kzalloc - allocate memory. The memory is set to zero.
* @size: how many bytes of memory are required.
* @flags: the type of memory to allocate (see kmalloc).
*/
static inline __alloc_size(1) void *kzalloc_noprof(size_t size, gfp_t flags)
{
return kmalloc_noprof(size, flags | __GFP_ZERO);
}
#define kzalloc(...) alloc_hooks(kzalloc_noprof(__VA_ARGS__))
#define kzalloc_node(_size, _flags, _node) kmalloc_node(_size, (_flags)|__GFP_ZERO, _node)
void *__kvmalloc_node_noprof(DECL_BUCKET_PARAMS(size, b), gfp_t flags, int node) __alloc_size(1);
#define kvmalloc_node_noprof(size, flags, node) \
__kvmalloc_node_noprof(PASS_BUCKET_PARAMS(size, NULL), flags, node)
#define kvmalloc_node(...) alloc_hooks(kvmalloc_node_noprof(__VA_ARGS__))
#define kvmalloc(_size, _flags) kvmalloc_node(_size, _flags, NUMA_NO_NODE)
#define kvmalloc_noprof(_size, _flags) kvmalloc_node_noprof(_size, _flags, NUMA_NO_NODE)
#define kvzalloc(_size, _flags) kvmalloc(_size, (_flags)|__GFP_ZERO)
#define kvzalloc_node(_size, _flags, _node) kvmalloc_node(_size, (_flags)|__GFP_ZERO, _node)
#define kmem_buckets_valloc(_b, _size, _flags) \
alloc_hooks(__kvmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE))
static inline __alloc_size(1, 2) void *
kvmalloc_array_node_noprof(size_t n, size_t size, gfp_t flags, int node)
{
size_t bytes;
if (unlikely(check_mul_overflow(n, size, &bytes)))
return NULL;
return kvmalloc_node_noprof(bytes, flags, node);
}
#define kvmalloc_array_noprof(...) kvmalloc_array_node_noprof(__VA_ARGS__, NUMA_NO_NODE)
#define kvcalloc_node_noprof(_n,_s,_f,_node) kvmalloc_array_node_noprof(_n,_s,(_f)|__GFP_ZERO,_node)
#define kvcalloc_noprof(...) kvcalloc_node_noprof(__VA_ARGS__, NUMA_NO_NODE)
#define kvmalloc_array(...) alloc_hooks(kvmalloc_array_noprof(__VA_ARGS__))
#define kvcalloc_node(...) alloc_hooks(kvcalloc_node_noprof(__VA_ARGS__))
#define kvcalloc(...) alloc_hooks(kvcalloc_noprof(__VA_ARGS__))
extern void *kvrealloc_noprof(const void *p, size_t oldsize, size_t newsize, gfp_t flags)
__realloc_size(3);
#define kvrealloc(...) alloc_hooks(kvrealloc_noprof(__VA_ARGS__))
extern void kvfree(const void *addr);
DEFINE_FREE(kvfree, void *, if (!IS_ERR_OR_NULL(_T)) kvfree(_T))
extern void kvfree_sensitive(const void *addr, size_t len);
unsigned int kmem_cache_size(struct kmem_cache *s);
/**
* kmalloc_size_roundup - Report allocation bucket size for the given size
*
* @size: Number of bytes to round up from.
*
* This returns the number of bytes that would be available in a kmalloc()
* allocation of @size bytes. For example, a 126 byte request would be
* rounded up to the next sized kmalloc bucket, 128 bytes. (This is strictly
* for the general-purpose kmalloc()-based allocations, and is not for the
* pre-sized kmem_cache_alloc()-based allocations.)
*
* Use this to kmalloc() the full bucket size ahead of time instead of using
* ksize() to query the size after an allocation.
*/
size_t kmalloc_size_roundup(size_t size);
void __init kmem_cache_init_late(void);
#endif /* _LINUX_SLAB_H */
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