--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/linux/slab.h	Sun Jan 11 20:20:11 2009 +0100
@@ -0,0 +1,319 @@
+/*
+ * 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.
+ */
+
+#ifndef _LINUX_SLAB_H
+#define	_LINUX_SLAB_H
+
+#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 */
+/*
+ * SLAB_DESTROY_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();
+ *
+ * See also the comment on struct slab_rcu in mm/slab.c.
+ */
+#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 */
+
+/* Flag to prevent checks on free */
+#ifdef CONFIG_DEBUG_OBJECTS
+# define SLAB_DEBUG_OBJECTS	0x00400000UL
+#else
+# define SLAB_DEBUG_OBJECTS	0x00000000UL
+#endif
+
+/* 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 (*)(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 * __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 (size != 0 && n > ULONG_MAX / size)
+		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);
+}
+
+/**
+ * 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 void *kzalloc_node(size_t size, gfp_t flags, int node)
+{
+	return kmalloc_node(size, flags | __GFP_ZERO, node);
+}
+
+#endif	/* _LINUX_SLAB_H */