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/*

 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).

 *

 * (C) SGI 2006, Christoph Lameter <clameter@sgi.com>

 *      Cleaned up and restructured to ease the addition of alternative

 *      implementations of SLAB allocators.

 */

#ifndef _LINUX_SLAB_H

#define _LINUX_SLAB_H

#ifdef __KERNEL__

#include <linux/gfp.h>

#include <linux/types.h>

/*

 * Flags to pass to kmem_cache_create().

 * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set.

 */

#define SLAB_DEBUG_FREE         0x00000100UL    /* DEBUG: Perform (expensive) checks on free */

#define SLAB_RED_ZONE           0x00000400UL    /* DEBUG: Red zone objs in a cache */

#define SLAB_POISON             0x00000800UL    /* DEBUG: Poison objects */

#define SLAB_HWCACHE_ALIGN      0x00002000UL    /* Align objs on cache lines */

#define SLAB_CACHE_DMA          0x00004000UL    /* Use GFP_DMA memory */

#define SLAB_STORE_USER         0x00010000UL    /* DEBUG: Store the last owner for bug hunting */

#define SLAB_PANIC              0x00040000UL    /* Panic if kmem_cache_create() fails */

#define SLAB_DESTROY_BY_RCU     0x00080000UL    /* Defer freeing slabs to RCU */

#define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */

#define SLAB_TRACE              0x00200000UL    /* Trace allocations and frees */

/* The following flags affect the page allocator grouping pages by mobility */

#define SLAB_RECLAIM_ACCOUNT    0x00020000UL            /* Objects are reclaimable */

#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)

/*

 * struct kmem_cache related prototypes

 */

void __init kmem_cache_init(void);

int slab_is_available(void);

struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,

                        unsigned long,

                        void (*)(struct kmem_cache *, void *));

void kmem_cache_destroy(struct kmem_cache *);

int kmem_cache_shrink(struct kmem_cache *);

void kmem_cache_free(struct kmem_cache *, void *);

unsigned int kmem_cache_size(struct kmem_cache *);

const char *kmem_cache_name(struct kmem_cache *);

int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr);

/*

 * 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)

/*

 * The largest kmalloc size supported by the slab allocators is

 * 32 megabyte (2^25) or the maximum allocatable page order if that is

 * less than 32 MB.

 *

 * WARNING: Its not easy to increase this value since the allocators have

 * to do various tricks to work around compiler limitations in order to

 * ensure proper constant folding.

 */

#define KMALLOC_SHIFT_HIGH      ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \

                                (MAX_ORDER + PAGE_SHIFT - 1) : 25)

#define KMALLOC_MAX_SIZE        (1UL << KMALLOC_SHIFT_HIGH)

#define KMALLOC_MAX_ORDER       (KMALLOC_SHIFT_HIGH - PAGE_SHIFT)

/*

 * Common kmalloc functions provided by all allocators

 */

void * __must_check krealloc(const void *, size_t, gfp_t);

void kfree(const void *);

size_t ksize(const void *);

/*

 * Allocator specific definitions. These are mainly used to establish optimized

 * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by

 * selecting the appropriate general cache at compile time.

 *

 * Allocators must define at least:

 *

 *      kmem_cache_alloc()

 *      __kmalloc()

 *      kmalloc()

 *

 * Those wishing to support NUMA must also define:

 *

 *      kmem_cache_alloc_node()

 *      kmalloc_node()

 *

 * See each allocator definition file for additional comments and

 * implementation notes.

 */

#ifdef CONFIG_SLUB

#include <linux/slub_def.h>

#elif defined(CONFIG_SLOB)

#include <linux/slob_def.h>

#else

#include <linux/slab_def.h>

#endif

/**

 * 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.

 *

 * 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.  May use emergency pools.

 *   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.

 *

 * %GFP_NOWAIT - Allocation will not sleep.

 *

 * %GFP_THISNODE - Allocate node-local memory only.

 *

 * %GFP_DMA - Allocation suitable for DMA.

 *   Should only be used for kmalloc() caches. Otherwise, use a

 *   slab created with SLAB_DMA.

 *

 * 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_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_REPEAT - If allocation fails initially, try once more before failing.

 *

 * There are other flags available as well, but these are not intended

 * for general use, and so are not documented here. For a full list of

 * potential flags, always refer to linux/gfp.h.

 */

static inline void *kcalloc(size_t n, size_t size, gfp_t flags)

{

        if (n != 0 && size > ULONG_MAX / n)

                return NULL;

        return __kmalloc(n * size, flags | __GFP_ZERO);

}

#if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB)

/**

 * kmalloc_node - allocate memory from a specific node

 * @size: how many bytes of memory are required.

 * @flags: the type of memory to allocate (see kcalloc).

 * @node: node to allocate from.

 *

 * kmalloc() for non-local nodes, used to allocate from a specific node

 * if available. Equivalent to kmalloc() in the non-NUMA single-node

 * case.

 */

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(size, flags);

}

void *kmem_cache_alloc(struct kmem_cache *, gfp_t);

static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,

                                        gfp_t flags, int node)

{

        return kmem_cache_alloc(cachep, flags);

}

#endif /* !CONFIG_NUMA && !CONFIG_SLOB */

/*

 * 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.

 */

#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)

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))

#else

#define kmalloc_track_caller(size, flags) \

        __kmalloc(size, flags)

#endif /* DEBUG_SLAB */

#ifdef CONFIG_NUMA

/*

 * 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.

 */

#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)

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))

#else

#define kmalloc_node_track_caller(size, flags, node) \

        __kmalloc_node(size, flags, node)

#endif

#else /* CONFIG_NUMA */

#define kmalloc_node_track_caller(size, flags, node) \

        kmalloc_track_caller(size, flags)

#endif /* DEBUG_SLAB */

/*

 * 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 void *kzalloc(size_t size, gfp_t flags)

{

        return kmalloc(size, flags | __GFP_ZERO);

}

#ifdef CONFIG_SLABINFO

extern const struct seq_operations slabinfo_op;

ssize_t slabinfo_write(struct file *, const char __user *, size_t, loff_t *);

#endif

#endif  /* __KERNEL__ */

#endif  /* _LINUX_SLAB_H */