Slab API: remove useless ctor parameter and reorder parameters
[linux-2.6/mini2440.git] / include / linux / slab.h
blobf3a8eecd99f3c4b5eb68d10389e3b96546699f4d
1 /*
2 * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
4 * (C) SGI 2006, Christoph Lameter <clameter@sgi.com>
5 * Cleaned up and restructured to ease the addition of alternative
6 * implementations of SLAB allocators.
7 */
9 #ifndef _LINUX_SLAB_H
10 #define _LINUX_SLAB_H
12 #ifdef __KERNEL__
14 #include <linux/gfp.h>
15 #include <linux/types.h>
18 * Flags to pass to kmem_cache_create().
19 * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set.
21 #define SLAB_DEBUG_FREE 0x00000100UL /* DEBUG: Perform (expensive) checks on free */
22 #define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */
23 #define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */
24 #define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */
25 #define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */
26 #define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */
27 #define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */
28 #define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */
29 #define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */
30 #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */
32 /* The following flags affect the page allocator grouping pages by mobility */
33 #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
34 #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
36 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
38 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
40 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
41 * Both make kfree a no-op.
43 #define ZERO_SIZE_PTR ((void *)16)
45 #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
46 (unsigned long)ZERO_SIZE_PTR)
49 * struct kmem_cache related prototypes
51 void __init kmem_cache_init(void);
52 int slab_is_available(void);
54 struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
55 unsigned long,
56 void (*)(struct kmem_cache *, void *));
57 void kmem_cache_destroy(struct kmem_cache *);
58 int kmem_cache_shrink(struct kmem_cache *);
59 void kmem_cache_free(struct kmem_cache *, void *);
60 unsigned int kmem_cache_size(struct kmem_cache *);
61 const char *kmem_cache_name(struct kmem_cache *);
62 int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr);
65 * Please use this macro to create slab caches. Simply specify the
66 * name of the structure and maybe some flags that are listed above.
68 * The alignment of the struct determines object alignment. If you
69 * f.e. add ____cacheline_aligned_in_smp to the struct declaration
70 * then the objects will be properly aligned in SMP configurations.
72 #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
73 sizeof(struct __struct), __alignof__(struct __struct),\
74 (__flags), NULL)
77 * The largest kmalloc size supported by the slab allocators is
78 * 32 megabyte (2^25) or the maximum allocatable page order if that is
79 * less than 32 MB.
81 * WARNING: Its not easy to increase this value since the allocators have
82 * to do various tricks to work around compiler limitations in order to
83 * ensure proper constant folding.
85 #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
86 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
88 #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH)
89 #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT)
92 * Common kmalloc functions provided by all allocators
94 void * __must_check krealloc(const void *, size_t, gfp_t);
95 void kfree(const void *);
96 size_t ksize(const void *);
99 * Allocator specific definitions. These are mainly used to establish optimized
100 * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by
101 * selecting the appropriate general cache at compile time.
103 * Allocators must define at least:
105 * kmem_cache_alloc()
106 * __kmalloc()
107 * kmalloc()
109 * Those wishing to support NUMA must also define:
111 * kmem_cache_alloc_node()
112 * kmalloc_node()
114 * See each allocator definition file for additional comments and
115 * implementation notes.
117 #ifdef CONFIG_SLUB
118 #include <linux/slub_def.h>
119 #elif defined(CONFIG_SLOB)
120 #include <linux/slob_def.h>
121 #else
122 #include <linux/slab_def.h>
123 #endif
126 * kcalloc - allocate memory for an array. The memory is set to zero.
127 * @n: number of elements.
128 * @size: element size.
129 * @flags: the type of memory to allocate.
131 * The @flags argument may be one of:
133 * %GFP_USER - Allocate memory on behalf of user. May sleep.
135 * %GFP_KERNEL - Allocate normal kernel ram. May sleep.
137 * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools.
138 * For example, use this inside interrupt handlers.
140 * %GFP_HIGHUSER - Allocate pages from high memory.
142 * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
144 * %GFP_NOFS - Do not make any fs calls while trying to get memory.
146 * %GFP_NOWAIT - Allocation will not sleep.
148 * %GFP_THISNODE - Allocate node-local memory only.
150 * %GFP_DMA - Allocation suitable for DMA.
151 * Should only be used for kmalloc() caches. Otherwise, use a
152 * slab created with SLAB_DMA.
154 * Also it is possible to set different flags by OR'ing
155 * in one or more of the following additional @flags:
157 * %__GFP_COLD - Request cache-cold pages instead of
158 * trying to return cache-warm pages.
160 * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
162 * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
163 * (think twice before using).
165 * %__GFP_NORETRY - If memory is not immediately available,
166 * then give up at once.
168 * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
170 * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
172 * There are other flags available as well, but these are not intended
173 * for general use, and so are not documented here. For a full list of
174 * potential flags, always refer to linux/gfp.h.
176 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
178 if (n != 0 && size > ULONG_MAX / n)
179 return NULL;
180 return __kmalloc(n * size, flags | __GFP_ZERO);
183 #if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB)
185 * kmalloc_node - allocate memory from a specific node
186 * @size: how many bytes of memory are required.
187 * @flags: the type of memory to allocate (see kcalloc).
188 * @node: node to allocate from.
190 * kmalloc() for non-local nodes, used to allocate from a specific node
191 * if available. Equivalent to kmalloc() in the non-NUMA single-node
192 * case.
194 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
196 return kmalloc(size, flags);
199 static inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
201 return __kmalloc(size, flags);
204 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
206 static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
207 gfp_t flags, int node)
209 return kmem_cache_alloc(cachep, flags);
211 #endif /* !CONFIG_NUMA && !CONFIG_SLOB */
214 * kmalloc_track_caller is a special version of kmalloc that records the
215 * calling function of the routine calling it for slab leak tracking instead
216 * of just the calling function (confusing, eh?).
217 * It's useful when the call to kmalloc comes from a widely-used standard
218 * allocator where we care about the real place the memory allocation
219 * request comes from.
221 #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
222 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
223 #define kmalloc_track_caller(size, flags) \
224 __kmalloc_track_caller(size, flags, __builtin_return_address(0))
225 #else
226 #define kmalloc_track_caller(size, flags) \
227 __kmalloc(size, flags)
228 #endif /* DEBUG_SLAB */
230 #ifdef CONFIG_NUMA
232 * kmalloc_node_track_caller is a special version of kmalloc_node that
233 * records the calling function of the routine calling it for slab leak
234 * tracking instead of just the calling function (confusing, eh?).
235 * It's useful when the call to kmalloc_node comes from a widely-used
236 * standard allocator where we care about the real place the memory
237 * allocation request comes from.
239 #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
240 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
241 #define kmalloc_node_track_caller(size, flags, node) \
242 __kmalloc_node_track_caller(size, flags, node, \
243 __builtin_return_address(0))
244 #else
245 #define kmalloc_node_track_caller(size, flags, node) \
246 __kmalloc_node(size, flags, node)
247 #endif
249 #else /* CONFIG_NUMA */
251 #define kmalloc_node_track_caller(size, flags, node) \
252 kmalloc_track_caller(size, flags)
254 #endif /* DEBUG_SLAB */
257 * Shortcuts
259 static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
261 return kmem_cache_alloc(k, flags | __GFP_ZERO);
265 * kzalloc - allocate memory. The memory is set to zero.
266 * @size: how many bytes of memory are required.
267 * @flags: the type of memory to allocate (see kmalloc).
269 static inline void *kzalloc(size_t size, gfp_t flags)
271 return kmalloc(size, flags | __GFP_ZERO);
274 #endif /* __KERNEL__ */
275 #endif /* _LINUX_SLAB_H */