757 строки
24 KiB
C
757 строки
24 KiB
C
/* 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/gfp.h>
|
|
#include <linux/overflow.h>
|
|
#include <linux/types.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/percpu-refcount.h>
|
|
|
|
|
|
/*
|
|
* Flags to pass to kmem_cache_create().
|
|
* The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
|
|
*/
|
|
/* DEBUG: Perform (expensive) checks on alloc/free */
|
|
#define SLAB_CONSISTENCY_CHECKS ((slab_flags_t __force)0x00000100U)
|
|
/* DEBUG: Red zone objs in a cache */
|
|
#define SLAB_RED_ZONE ((slab_flags_t __force)0x00000400U)
|
|
/* DEBUG: Poison objects */
|
|
#define SLAB_POISON ((slab_flags_t __force)0x00000800U)
|
|
/* Indicate a kmalloc slab */
|
|
#define SLAB_KMALLOC ((slab_flags_t __force)0x00001000U)
|
|
/* Align objs on cache lines */
|
|
#define SLAB_HWCACHE_ALIGN ((slab_flags_t __force)0x00002000U)
|
|
/* Use GFP_DMA memory */
|
|
#define SLAB_CACHE_DMA ((slab_flags_t __force)0x00004000U)
|
|
/* Use GFP_DMA32 memory */
|
|
#define SLAB_CACHE_DMA32 ((slab_flags_t __force)0x00008000U)
|
|
/* DEBUG: Store the last owner for bug hunting */
|
|
#define SLAB_STORE_USER ((slab_flags_t __force)0x00010000U)
|
|
/* Panic if kmem_cache_create() fails */
|
|
#define SLAB_PANIC ((slab_flags_t __force)0x00040000U)
|
|
/*
|
|
* 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:
|
|
*
|
|
* rcu_read_lock()
|
|
* again:
|
|
* obj = lockless_lookup(key);
|
|
* if (obj) {
|
|
* if (!try_get_ref(obj)) // might fail for free objects
|
|
* goto again;
|
|
*
|
|
* if (obj->key != key) { // not the object we expected
|
|
* put_ref(obj);
|
|
* goto again;
|
|
* }
|
|
* }
|
|
* 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_flags_t __force)0x00080000U)
|
|
/* Spread some memory over cpuset */
|
|
#define SLAB_MEM_SPREAD ((slab_flags_t __force)0x00100000U)
|
|
/* Trace allocations and frees */
|
|
#define SLAB_TRACE ((slab_flags_t __force)0x00200000U)
|
|
|
|
/* Flag to prevent checks on free */
|
|
#ifdef CONFIG_DEBUG_OBJECTS
|
|
# define SLAB_DEBUG_OBJECTS ((slab_flags_t __force)0x00400000U)
|
|
#else
|
|
# define SLAB_DEBUG_OBJECTS 0
|
|
#endif
|
|
|
|
/* Avoid kmemleak tracing */
|
|
#define SLAB_NOLEAKTRACE ((slab_flags_t __force)0x00800000U)
|
|
|
|
/* Fault injection mark */
|
|
#ifdef CONFIG_FAILSLAB
|
|
# define SLAB_FAILSLAB ((slab_flags_t __force)0x02000000U)
|
|
#else
|
|
# define SLAB_FAILSLAB 0
|
|
#endif
|
|
/* Account to memcg */
|
|
#ifdef CONFIG_MEMCG_KMEM
|
|
# define SLAB_ACCOUNT ((slab_flags_t __force)0x04000000U)
|
|
#else
|
|
# define SLAB_ACCOUNT 0
|
|
#endif
|
|
|
|
#ifdef CONFIG_KASAN_GENERIC
|
|
#define SLAB_KASAN ((slab_flags_t __force)0x08000000U)
|
|
#else
|
|
#define SLAB_KASAN 0
|
|
#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_flags_t __force)0x10000000U)
|
|
|
|
#ifdef CONFIG_KFENCE
|
|
#define SLAB_SKIP_KFENCE ((slab_flags_t __force)0x20000000U)
|
|
#else
|
|
#define SLAB_SKIP_KFENCE 0
|
|
#endif
|
|
|
|
/* The following flags affect the page allocator grouping pages by mobility */
|
|
/* Objects are reclaimable */
|
|
#ifndef CONFIG_SLUB_TINY
|
|
#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U)
|
|
#else
|
|
#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0)
|
|
#endif
|
|
#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
|
|
|
|
/*
|
|
* 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(const void *objp, size_t new_size, gfp_t flags) __realloc_size(2);
|
|
void kfree(const void *objp);
|
|
void kfree_sensitive(const void *objp);
|
|
size_t __ksize(const void *objp);
|
|
|
|
/**
|
|
* 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_valid_obj(void *object);
|
|
void kmem_dump_obj(void *object);
|
|
#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.
|
|
*/
|
|
#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
|
|
#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
|
|
#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
|
|
#define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
|
|
#else
|
|
#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
|
|
#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
|
|
*/
|
|
|
|
#ifdef CONFIG_SLAB
|
|
/*
|
|
* SLAB and 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_ORDER + PAGE_SHIFT)
|
|
#ifndef KMALLOC_SHIFT_LOW
|
|
#define KMALLOC_SHIFT_LOW 5
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef CONFIG_SLUB
|
|
#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
|
|
#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT)
|
|
#ifndef KMALLOC_SHIFT_LOW
|
|
#define KMALLOC_SHIFT_LOW 3
|
|
#endif
|
|
#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)
|
|
|
|
/*
|
|
* 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
|
|
#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
|
|
};
|
|
|
|
extern struct kmem_cache *
|
|
kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1];
|
|
|
|
/*
|
|
* 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))
|
|
|
|
static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags)
|
|
{
|
|
/*
|
|
* 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))
|
|
return KMALLOC_NORMAL;
|
|
|
|
/*
|
|
* 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)
|
|
|
|
void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1);
|
|
|
|
/**
|
|
* 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(struct kmem_cache *cachep, gfp_t flags) __assume_slab_alignment __malloc;
|
|
void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru,
|
|
gfp_t gfpflags) __assume_slab_alignment __malloc;
|
|
void kmem_cache_free(struct kmem_cache *s, void *objp);
|
|
|
|
/*
|
|
* 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(struct kmem_cache *s, gfp_t flags, size_t size, void **p);
|
|
|
|
static __always_inline void kfree_bulk(size_t size, void **p)
|
|
{
|
|
kmem_cache_free_bulk(NULL, size, p);
|
|
}
|
|
|
|
void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment
|
|
__alloc_size(1);
|
|
void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node) __assume_slab_alignment
|
|
__malloc;
|
|
|
|
void *kmalloc_trace(struct kmem_cache *s, gfp_t flags, size_t size)
|
|
__assume_kmalloc_alignment __alloc_size(3);
|
|
|
|
void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags,
|
|
int node, size_t size) __assume_kmalloc_alignment
|
|
__alloc_size(4);
|
|
void *kmalloc_large(size_t size, gfp_t flags) __assume_page_alignment
|
|
__alloc_size(1);
|
|
|
|
void *kmalloc_large_node(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.
|
|
*
|
|
* 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(size_t size, gfp_t flags)
|
|
{
|
|
if (__builtin_constant_p(size) && size) {
|
|
unsigned int index;
|
|
|
|
if (size > KMALLOC_MAX_CACHE_SIZE)
|
|
return kmalloc_large(size, flags);
|
|
|
|
index = kmalloc_index(size);
|
|
return kmalloc_trace(
|
|
kmalloc_caches[kmalloc_type(flags)][index],
|
|
flags, size);
|
|
}
|
|
return __kmalloc(size, flags);
|
|
}
|
|
|
|
static __always_inline __alloc_size(1) void *kmalloc_node(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(size, flags, node);
|
|
|
|
index = kmalloc_index(size);
|
|
return kmalloc_node_trace(
|
|
kmalloc_caches[kmalloc_type(flags)][index],
|
|
flags, node, size);
|
|
}
|
|
return __kmalloc_node(size, flags, node);
|
|
}
|
|
|
|
/**
|
|
* 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(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(bytes, flags);
|
|
return __kmalloc(bytes, flags);
|
|
}
|
|
|
|
/**
|
|
* 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(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(p, bytes, flags);
|
|
}
|
|
|
|
/**
|
|
* 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).
|
|
*/
|
|
static inline __alloc_size(1, 2) void *kcalloc(size_t n, size_t size, gfp_t flags)
|
|
{
|
|
return kmalloc_array(n, size, flags | __GFP_ZERO);
|
|
}
|
|
|
|
void *__kmalloc_node_track_caller(size_t size, gfp_t flags, int node,
|
|
unsigned long caller) __alloc_size(1);
|
|
#define kmalloc_node_track_caller(size, flags, node) \
|
|
__kmalloc_node_track_caller(size, flags, node, \
|
|
_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(size, flags) \
|
|
__kmalloc_node_track_caller(size, flags, \
|
|
NUMA_NO_NODE, _RET_IP_)
|
|
|
|
static inline __alloc_size(1, 2) void *kmalloc_array_node(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(bytes, flags, node);
|
|
return __kmalloc_node(bytes, flags, node);
|
|
}
|
|
|
|
static inline __alloc_size(1, 2) void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node)
|
|
{
|
|
return kmalloc_array_node(n, size, flags | __GFP_ZERO, node);
|
|
}
|
|
|
|
/*
|
|
* Shortcuts
|
|
*/
|
|
static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
|
|
{
|
|
return 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(size_t size, gfp_t flags)
|
|
{
|
|
return kmalloc(size, flags | __GFP_ZERO);
|
|
}
|
|
|
|
/**
|
|
* kzalloc_node - allocate zeroed memory from a particular memory node.
|
|
* @size: how many bytes of memory are required.
|
|
* @flags: the type of memory to allocate (see kmalloc).
|
|
* @node: memory node from which to allocate
|
|
*/
|
|
static inline __alloc_size(1) void *kzalloc_node(size_t size, gfp_t flags, int node)
|
|
{
|
|
return kmalloc_node(size, flags | __GFP_ZERO, node);
|
|
}
|
|
|
|
extern void *kvmalloc_node(size_t size, gfp_t flags, int node) __alloc_size(1);
|
|
static inline __alloc_size(1) void *kvmalloc(size_t size, gfp_t flags)
|
|
{
|
|
return kvmalloc_node(size, flags, NUMA_NO_NODE);
|
|
}
|
|
static inline __alloc_size(1) void *kvzalloc_node(size_t size, gfp_t flags, int node)
|
|
{
|
|
return kvmalloc_node(size, flags | __GFP_ZERO, node);
|
|
}
|
|
static inline __alloc_size(1) void *kvzalloc(size_t size, gfp_t flags)
|
|
{
|
|
return kvmalloc(size, flags | __GFP_ZERO);
|
|
}
|
|
|
|
static inline __alloc_size(1, 2) void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
|
|
{
|
|
size_t bytes;
|
|
|
|
if (unlikely(check_mul_overflow(n, size, &bytes)))
|
|
return NULL;
|
|
|
|
return kvmalloc(bytes, flags);
|
|
}
|
|
|
|
static inline __alloc_size(1, 2) void *kvcalloc(size_t n, size_t size, gfp_t flags)
|
|
{
|
|
return kvmalloc_array(n, size, flags | __GFP_ZERO);
|
|
}
|
|
|
|
extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize, gfp_t flags)
|
|
__realloc_size(3);
|
|
extern void kvfree(const void *addr);
|
|
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);
|
|
|
|
#if defined(CONFIG_SMP) && defined(CONFIG_SLAB)
|
|
int slab_prepare_cpu(unsigned int cpu);
|
|
int slab_dead_cpu(unsigned int cpu);
|
|
#else
|
|
#define slab_prepare_cpu NULL
|
|
#define slab_dead_cpu NULL
|
|
#endif
|
|
|
|
#endif /* _LINUX_SLAB_H */
|