slab.h

/*
 * linux/include/linux/slab.h
 * Written by Mark Hemment, 1996.
 * (markhe@nextd.demon.co.uk)
 */

#ifndef _LINUX_SLAB_H
#define	_LINUX_SLAB_H

#if	defined(__KERNEL__)

/* kmem_cache_t exists for legacy reasons and is not used by code in mm */
typedef struct kmem_cache kmem_cache_t;

#include	<linux/gfp.h>
#include	<linux/init.h>
#include	<linux/types.h>
#include	<asm/page.h>		/* kmalloc_sizes.h needs PAGE_SIZE */
#include	<asm/cache.h>		/* kmalloc_sizes.h needs L1_CACHE_BYTES */

/* flags to pass to kmem_cache_create().
 * The first 3 are only valid when the allocator as been build
 * SLAB_DEBUG_SUPPORT.
 */
#define	SLAB_DEBUG_FREE		0x00000100UL	/* Peform (expensive) checks on free */
#define	SLAB_DEBUG_INITIAL	0x00000200UL	/* Call constructor (as verifier) */
#define	SLAB_RED_ZONE		0x00000400UL	/* Red zone objs in a cache */
#define	SLAB_POISON		0x00000800UL	/* Poison objects */
#define	SLAB_HWCACHE_ALIGN	0x00002000UL	/* align objs on a h/w cache lines */
#define SLAB_CACHE_DMA		0x00004000UL	/* use GFP_DMA memory */
#define SLAB_MUST_HWCACHE_ALIGN	0x00008000UL	/* force alignment */
#define SLAB_STORE_USER		0x00010000UL	/* store the last owner for bug hunting */
#define SLAB_RECLAIM_ACCOUNT	0x00020000UL	/* track pages allocated to indicate
						   what is reclaimable later*/
#define SLAB_PANIC		0x00040000UL	/* panic if kmem_cache_create() fails */
#define SLAB_DESTROY_BY_RCU	0x00080000UL	/* defer freeing pages to RCU */
#define SLAB_MEM_SPREAD		0x00100000UL	/* Spread some memory over cpuset */

/* flags passed to a constructor func */
#define	SLAB_CTOR_CONSTRUCTOR	0x001UL		/* if not set, then deconstructor */
#define SLAB_CTOR_ATOMIC	0x002UL		/* tell constructor it can't sleep */
#define	SLAB_CTOR_VERIFY	0x004UL		/* tell constructor it's a verify call */

#ifndef CONFIG_SLOB

/* prototypes */
extern void __init kmem_cache_init(void);

extern struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
			unsigned long,
			void (*)(void *, struct kmem_cache *, unsigned long),
			void (*)(void *, struct kmem_cache *, unsigned long));
extern void kmem_cache_destroy(struct kmem_cache *);
extern int kmem_cache_shrink(struct kmem_cache *);
extern void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
extern void kmem_cache_free(struct kmem_cache *, void *);
extern unsigned int kmem_cache_size(struct kmem_cache *);
extern const char *kmem_cache_name(struct kmem_cache *);

/* Size description struct for general caches. */
struct cache_sizes {
	size_t		 	cs_size;
	struct kmem_cache	*cs_cachep;
	struct kmem_cache	*cs_dmacachep;
};
extern struct cache_sizes malloc_sizes[];

extern void *__kmalloc(size_t, gfp_t);

/**
 * kmalloc - allocate memory
 * @size: how many bytes of memory are required.
 * @flags: the type of memory to allocate.
 *
 * kmalloc is the normal method of allocating memory
 * in the kernel.
 *
 * The @flags argument may be one of:
 *
 * %GFP_USER - Allocate memory on behalf of user.  May sleep.
 *
 * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
 *
 * %GFP_ATOMIC - Allocation will not sleep.
 *   For example, use this inside interrupt handlers.
 *
 * %GFP_HIGHUSER - Allocate pages from high memory.
 *
 * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
 *
 * %GFP_NOFS - Do not make any fs calls while trying to get memory.
 *
 * Also it is possible to set different flags by OR'ing
 * in one or more of the following additional @flags:
 *
 * %__GFP_COLD - Request cache-cold pages instead of
 *   trying to return cache-warm pages.
 *
 * %__GFP_DMA - Request memory from the DMA-capable zone.
 *
 * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
 *
 * %__GFP_HIGHMEM - Allocated memory may be from highmem.
 *
 * %__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_REPEAT - If allocation fails initially, try once more before failing.
 */
static inline void *kmalloc(size_t size, gfp_t flags)
{
	if (__builtin_constant_p(size)) {
		int i = 0;
#define CACHE(x) \
		if (size <= x) \
			goto found; \
		else \
			i++;
#include "kmalloc_sizes.h"
#undef CACHE
		{
			extern void __you_cannot_kmalloc_that_much(void);
			__you_cannot_kmalloc_that_much();
		}
found:
		return kmem_cache_alloc((flags & GFP_DMA) ?
			malloc_sizes[i].cs_dmacachep :
			malloc_sizes[i].cs_cachep, flags);
	}
	return __kmalloc(size, flags);
}

/*
 * 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.
 */
#ifndef CONFIG_DEBUG_SLAB
#define kmalloc_track_caller(size, flags) \
	__kmalloc(size, flags)
#else
extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
#define kmalloc_track_caller(size, flags) \
	__kmalloc_track_caller(size, flags, __builtin_return_address(0))
#endif

extern void *__kzalloc(size_t, gfp_t);

/**
 * 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 void *kzalloc(size_t size, gfp_t flags)
{
	if (__builtin_constant_p(size)) {
		int i = 0;
#define CACHE(x) \
		if (size <= x) \
			goto found; \
		else \
			i++;
#include "kmalloc_sizes.h"
#undef CACHE
		{
			extern void __you_cannot_kzalloc_that_much(void);
			__you_cannot_kzalloc_that_much();
		}
found:
		return kmem_cache_zalloc((flags & GFP_DMA) ?
			malloc_sizes[i].cs_dmacachep :
			malloc_sizes[i].cs_cachep, flags);
	}
	return __kzalloc(size, 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.
 */
static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
{
	if (n != 0 && size > ULONG_MAX / n)
		return NULL;
	return kzalloc(n * size, flags);
}

extern void kfree(const void *);
extern unsigned int ksize(const void *);
extern int slab_is_available(void);

#ifdef CONFIG_NUMA
extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
extern void *__kmalloc_node(size_t size, gfp_t flags, int node);

static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
	if (__builtin_constant_p(size)) {
		int i = 0;
#define CACHE(x) \
		if (size <= x) \
			goto found; \
		else \
			i++;
#include "kmalloc_sizes.h"
#undef CACHE
		{
			extern void __you_cannot_kmalloc_that_much(void);
			__you_cannot_kmalloc_that_much();
		}
found:
		return kmem_cache_alloc_node((flags & GFP_DMA) ?
			malloc_sizes[i].cs_dmacachep :
			malloc_sizes[i].cs_cachep, flags, node);
	}
	return __kmalloc_node(size, flags, node);
}

/*
 * kmalloc_node_track_caller is a special version of kmalloc_node 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_node comes from a widely-used
 * standard allocator where we care about the real place the memory
 * allocation request comes from.
 */
#ifndef CONFIG_DEBUG_SLAB
#define kmalloc_node_track_caller(size, flags, node) \
	__kmalloc_node(size, flags, node)
#else
extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
#define kmalloc_node_track_caller(size, flags, node) \
	__kmalloc_node_track_caller(size, flags, node, \
			__builtin_return_address(0))
#endif
#else /* CONFIG_NUMA */
static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
					gfp_t flags, int node)
{
	return kmem_cache_alloc(cachep, flags);
}
static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
	return kmalloc(size, flags);
}

#define kmalloc_node_track_caller(size, flags, node) \
	kmalloc_track_caller(size, flags)
#endif

extern int FASTCALL(kmem_cache_reap(int));
extern int FASTCALL(kmem_ptr_validate(struct kmem_cache *cachep, void *ptr));

#else /* CONFIG_SLOB */

/* SLOB allocator routines */

void kmem_cache_init(void);
struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
	unsigned long,
	void (*)(void *, struct kmem_cache *, unsigned long),
	void (*)(void *, struct kmem_cache *, unsigned long));
void kmem_cache_destroy(struct kmem_cache *c);
void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
void kmem_cache_free(struct kmem_cache *c, void *b);
const char *kmem_cache_name(struct kmem_cache *);
void *kmalloc(size_t size, gfp_t flags);
void *__kzalloc(size_t size, gfp_t flags);
void kfree(const void *m);
unsigned int ksize(const void *m);
unsigned int kmem_cache_size(struct kmem_cache *c);

static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
{
	return __kzalloc(n * size, flags);
}

#define kmem_cache_shrink(d) (0)
#define kmem_cache_reap(a)
#define kmem_ptr_validate(a, b) (0)
#define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
#define kmalloc_node(s, f, n) kmalloc(s, f)
#define kzalloc(s, f) __kzalloc(s, f)
#define kmalloc_track_caller kmalloc

#define kmalloc_node_track_caller kmalloc_node

#endif /* CONFIG_SLOB */

#endif	/* __KERNEL__ */

#endif	/* _LINUX_SLAB_H */