source: GPL/trunk/include/linux/slab.h

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

#include <linux/gfp.h>
#include <linux/overflow.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/workqueue.h>

#if     !defined(_LINUX_SLAB_H)
#define _LINUX_SLAB_H

#if     defined(__KERNEL__)

typedef struct kmem_cache_s kmem_cache_t;

/* flags for kmem_cache_alloc() */
#define SLAB_BUFFER             GFP_BUFFER
#define SLAB_ATOMIC             GFP_ATOMIC
#define SLAB_USER               GFP_USER
#define SLAB_KERNEL             GFP_KERNEL
#define SLAB_NFS                GFP_NFS
#define SLAB_DMA                GFP_DMA

#define SLAB_LEVEL_MASK         0x0000007fUL
#define SLAB_NO_GROW            0x00001000UL    /* don't grow a cache */

/* 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_NO_REAP            0x00001000UL    /* never reap from the cache */
#define SLAB_HWCACHE_ALIGN      0x00002000UL    /* align objs on a h/w cache lines */
#if     0
#define SLAB_HIGH_PACK          0x00004000UL    /* XXX */
#endif

/* 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 */

#endif  /* __KERNEL__ */

/*
 * 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)

//NOTE: enabling this in the non-KEE driver causes problems (file name strings
//      put in seperate private segments)
#ifdef DEBUGHEAP
extern void near *__kmalloc(int, int, const char *filename, int lineno);
extern void  __kfree(const void near *, const char *filename, int lineno);

static inline void *kmalloc(size_t size, gfp_t flags)
{
        return __kmalloc(size, flags, __FILE__, __LINE__);
}


#define kfree(a)                __kfree(a, __FILE__, __LINE__)
#define kfree_s(a,b)            __kfree(a, __FILE__, __LINE__)
#define kfree_nocheck(a)        __kfree(a, __FILE__, __LINE__)

#else
extern void near *__kmalloc(int, int);
extern void  __kfree(const void near *);

#define kmalloc(a,b)            __kmalloc(a,b)
#define kfree(a)                __kfree(a)

#define kfree_s(a,b)            kfree(a)
#define kfree_nocheck(a)        kfree(a)
#endif

/**
 * 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)
{
        return kmalloc(size, flags | __GFP_ZERO);
}

void *kcalloc(size_t n, size_t size, unsigned int __nocast gfp_flags);
void *krealloc(const void *, size_t, gfp_t);

#define SIZE_MAX        (~(size_t)0)

/**
 * 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 void *kmalloc_array(size_t n, size_t size, gfp_t flags)
{
        if (size != 0 && n > SIZE_MAX / size)
                return NULL;
        return __kmalloc(n * size, 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 __must_check inline void *
krealloc_array(void *p, size_t new_n, size_t new_size, gfp_t flags)
{
//      size_t bytes;

//      if (check_mul_overflow(new_n, new_size, &bytes))
//              return NULL;

        return krealloc(p, new_n*new_size, flags);
}

#define kmalloc_node_track_caller(size, flags, node) \
        kmalloc_track_caller(size, flags)
#define         kmalloc_track_caller(size, flags)   __kmalloc(size, flags)
#define kvfree(arg)                     kfree(arg)

struct kmem_cache {
        unsigned int object_size;/* The original size of the object */
        unsigned int size;      /* The aligned/padded/added on size  */
        unsigned int align;     /* Alignment as calculated */
        unsigned long flags;    /* Active flags on the slab */
        const char *name;       /* Slab name for sysfs */
        int refcount;           /* Use counter */
        void (*ctor)(void *);   /* Called on object slot creation */
        struct list_head list;  /* List of all slab caches on the system */
};

size_t ksize(const void *);

static inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
{
        return __kmalloc(size, flags);
}

static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
        return __kmalloc_node(size, flags, node);
}

#endif  /* _LINUX_SLAB_H */