include/linux/slab.h

   1 /*
   2  * linux/include/linux/slab.h
   3  * Written by Mark Hemment, 1996.
   4  * (markhe@nextd.demon.co.uk)
   5  */
   6
   7 #ifndef _LINUX_SLAB_H
   8 #define _LINUX_SLAB_H
   9
  10 #if     defined(__KERNEL__)
  11
  12 typedef struct kmem_cache kmem_cache_t;
  13
  14 #include        <linux/gfp.h>
  15 #include        <linux/init.h>
  16 #include        <linux/types.h>
  17 #include        <asm/page.h>            /* kmalloc_sizes.h needs PAGE_SIZE */
  18 #include        <asm/cache.h>           /* kmalloc_sizes.h needs L1_CACHE_BYTES */
  19
  20 /* flags for kmem_cache_alloc() */
  21 #define SLAB_NOFS               GFP_NOFS
  22 #define SLAB_NOIO               GFP_NOIO
  23 #define SLAB_ATOMIC             GFP_ATOMIC
  24 #define SLAB_USER               GFP_USER
  25 #define SLAB_KERNEL             GFP_KERNEL
  26 #define SLAB_DMA                GFP_DMA
  27
  28 #define SLAB_LEVEL_MASK         GFP_LEVEL_MASK
  29
  30 #define SLAB_NO_GROW            __GFP_NO_GROW   /* don't grow a cache */
  31
  32 /* flags to pass to kmem_cache_create().
  33  * The first 3 are only valid when the allocator as been build
  34  * SLAB_DEBUG_SUPPORT.
  35  */
  36 #define SLAB_DEBUG_FREE         0x00000100UL    /* Peform (expensive) checks on free */
  37 #define SLAB_DEBUG_INITIAL      0x00000200UL    /* Call constructor (as verifier) */
  38 #define SLAB_RED_ZONE           0x00000400UL    /* Red zone objs in a cache */
  39 #define SLAB_POISON             0x00000800UL    /* Poison objects */
  40 #define SLAB_HWCACHE_ALIGN      0x00002000UL    /* align objs on a h/w cache lines */
  41 #define SLAB_CACHE_DMA          0x00004000UL    /* use GFP_DMA memory */
  42 #define SLAB_MUST_HWCACHE_ALIGN 0x00008000UL    /* force alignment */
  43 #define SLAB_STORE_USER         0x00010000UL    /* store the last owner for bug hunting */
  44 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL    /* track pages allocated to indicate
  45                                                    what is reclaimable later*/
  46 #define SLAB_PANIC              0x00040000UL    /* panic if kmem_cache_create() fails */
  47 #define SLAB_DESTROY_BY_RCU     0x00080000UL    /* defer freeing pages to RCU */
  48 #define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */
  49
  50 /* flags passed to a constructor func */
  51 #define SLAB_CTOR_CONSTRUCTOR   0x001UL         /* if not set, then deconstructor */
  52 #define SLAB_CTOR_ATOMIC        0x002UL         /* tell constructor it can't sleep */
  53 #define SLAB_CTOR_VERIFY        0x004UL         /* tell constructor it's a verify call */
  54
  55 #ifndef CONFIG_SLOB
  56
  57 /* prototypes */
  58 extern void __init kmem_cache_init(void);
  59
  60 extern kmem_cache_t *kmem_cache_create(const char *, size_t, size_t, unsigned long,
  61                                        void (*)(void *, kmem_cache_t *, unsigned long),
  62                                        void (*)(void *, kmem_cache_t *, unsigned long));
  63 extern void kmem_cache_destroy(kmem_cache_t *);
  64 extern int kmem_cache_shrink(kmem_cache_t *);
  65 extern void *kmem_cache_alloc(kmem_cache_t *, gfp_t);
  66 extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
  67 extern void kmem_cache_free(kmem_cache_t *, void *);
  68 extern unsigned int kmem_cache_size(kmem_cache_t *);
  69 extern const char *kmem_cache_name(kmem_cache_t *);
  70
  71 /* Size description struct for general caches. */
  72 struct cache_sizes {
  73         size_t           cs_size;
  74         kmem_cache_t    *cs_cachep;
  75         kmem_cache_t    *cs_dmacachep;
  76 };
  77 extern struct cache_sizes malloc_sizes[];
  78
  79 extern void *__kmalloc(size_t, gfp_t);
  80
  81 /**
  82  * kmalloc - allocate memory
  83  * @size: how many bytes of memory are required.
  84  * @flags: the type of memory to allocate.
  85  *
  86  * kmalloc is the normal method of allocating memory
  87  * in the kernel.
  88  *
  89  * The @flags argument may be one of:
  90  *
  91  * %GFP_USER - Allocate memory on behalf of user.  May sleep.
  92  *
  93  * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
  94  *
  95  * %GFP_ATOMIC - Allocation will not sleep.
  96  *   For example, use this inside interrupt handlers.
  97  *
  98  * %GFP_HIGHUSER - Allocate pages from high memory.
  99  *
 100  * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
 101  *
 102  * %GFP_NOFS - Do not make any fs calls while trying to get memory.
 103  *
 104  * Also it is possible to set different flags by OR'ing
 105  * in one or more of the following additional @flags:
 106  *
 107  * %__GFP_COLD - Request cache-cold pages instead of
 108  *   trying to return cache-warm pages.
 109  *
 110  * %__GFP_DMA - Request memory from the DMA-capable zone.
 111  *
 112  * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
 113  *
 114  * %__GFP_HIGHMEM - Allocated memory may be from highmem.
 115  *
 116  * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
 117  *   (think twice before using).
 118  *
 119  * %__GFP_NORETRY - If memory is not immediately available,
 120  *   then give up at once.
 121  *
 122  * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
 123  *
 124  * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
 125  */
 126 static inline void *kmalloc(size_t size, gfp_t flags)
 127 {
 128         if (__builtin_constant_p(size)) {
 129                 int i = 0;
 130 #define CACHE(x) \
 131                 if (size <= x) \
 132                         goto found; \
 133                 else \
 134                         i++;
 135 #include "kmalloc_sizes.h"
 136 #undef CACHE
 137                 {
 138                         extern void __you_cannot_kmalloc_that_much(void);
 139                         __you_cannot_kmalloc_that_much();
 140                 }
 141 found:
 142                 return kmem_cache_alloc((flags & GFP_DMA) ?
 143                         malloc_sizes[i].cs_dmacachep :
 144                         malloc_sizes[i].cs_cachep, flags);
 145         }
 146         return __kmalloc(size, flags);
 147 }
 148
 149 /*
 150  * kmalloc_track_caller is a special version of kmalloc that records the
 151  * calling function of the routine calling it for slab leak tracking instead
 152  * of just the calling function (confusing, eh?).
 153  * It's useful when the call to kmalloc comes from a widely-used standard
 154  * allocator where we care about the real place the memory allocation
 155  * request comes from.
 156  */
 157 #ifndef CONFIG_DEBUG_SLAB
 158 #define kmalloc_track_caller(size, flags) \
 159         __kmalloc(size, flags)
 160 #else
 161 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
 162 #define kmalloc_track_caller(size, flags) \
 163         __kmalloc_track_caller(size, flags, __builtin_return_address(0))
 164 #endif
 165
 166 extern void *__kzalloc(size_t, gfp_t);
 167
 168 /**
 169  * kzalloc - allocate memory. The memory is set to zero.
 170  * @size: how many bytes of memory are required.
 171  * @flags: the type of memory to allocate (see kmalloc).
 172  */
 173 static inline void *kzalloc(size_t size, gfp_t flags)
 174 {
 175         if (__builtin_constant_p(size)) {
 176                 int i = 0;
 177 #define CACHE(x) \
 178                 if (size <= x) \
 179                         goto found; \
 180                 else \
 181                         i++;
 182 #include "kmalloc_sizes.h"
 183 #undef CACHE
 184                 {
 185                         extern void __you_cannot_kzalloc_that_much(void);
 186                         __you_cannot_kzalloc_that_much();
 187                 }
 188 found:
 189                 return kmem_cache_zalloc((flags & GFP_DMA) ?
 190                         malloc_sizes[i].cs_dmacachep :
 191                         malloc_sizes[i].cs_cachep, flags);
 192         }
 193         return __kzalloc(size, flags);
 194 }
 195
 196 /**
 197  * kcalloc - allocate memory for an array. The memory is set to zero.
 198  * @n: number of elements.
 199  * @size: element size.
 200  * @flags: the type of memory to allocate.
 201  */
 202 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 203 {
 204         if (n != 0 && size > ULONG_MAX / n)
 205                 return NULL;
 206         return kzalloc(n * size, flags);
 207 }
 208
 209 extern void kfree(const void *);
 210 extern unsigned int ksize(const void *);
 211 extern int slab_is_available(void);
 212
 213 #ifdef CONFIG_NUMA
 214 extern void *kmem_cache_alloc_node(kmem_cache_t *, gfp_t flags, int node);
 215 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 216
 217 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 218 {
 219         if (__builtin_constant_p(size)) {
 220                 int i = 0;
 221 #define CACHE(x) \
 222                 if (size <= x) \
 223                         goto found; \
 224                 else \
 225                         i++;
 226 #include "kmalloc_sizes.h"
 227 #undef CACHE
 228                 {
 229                         extern void __you_cannot_kmalloc_that_much(void);
 230                         __you_cannot_kmalloc_that_much();
 231                 }
 232 found:
 233                 return kmem_cache_alloc_node((flags & GFP_DMA) ?
 234                         malloc_sizes[i].cs_dmacachep :
 235                         malloc_sizes[i].cs_cachep, flags, node);
 236         }
 237         return __kmalloc_node(size, flags, node);
 238 }
 239 #else
 240 static inline void *kmem_cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int node)
 241 {
 242         return kmem_cache_alloc(cachep, flags);
 243 }
 244 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 245 {
 246         return kmalloc(size, flags);
 247 }
 248 #endif
 249
 250 extern int FASTCALL(kmem_cache_reap(int));
 251 extern int FASTCALL(kmem_ptr_validate(kmem_cache_t *cachep, void *ptr));
 252
 253 #else /* CONFIG_SLOB */
 254
 255 /* SLOB allocator routines */
 256
 257 void kmem_cache_init(void);
 258 struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
 259         unsigned long,
 260         void (*)(void *, struct kmem_cache *, unsigned long),
 261         void (*)(void *, struct kmem_cache *, unsigned long));
 262 void kmem_cache_destroy(struct kmem_cache *c);
 263 void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
 264 void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
 265 void kmem_cache_free(struct kmem_cache *c, void *b);
 266 const char *kmem_cache_name(struct kmem_cache *);
 267 void *kmalloc(size_t size, gfp_t flags);
 268 void *__kzalloc(size_t size, gfp_t flags);
 269 void kfree(const void *m);
 270 unsigned int ksize(const void *m);
 271 unsigned int kmem_cache_size(struct kmem_cache *c);
 272
 273 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 274 {
 275         return __kzalloc(n * size, flags);
 276 }
 277
 278 #define kmem_cache_shrink(d) (0)
 279 #define kmem_cache_reap(a)
 280 #define kmem_ptr_validate(a, b) (0)
 281 #define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
 282 #define kmalloc_node(s, f, n) kmalloc(s, f)
 283 #define kzalloc(s, f) __kzalloc(s, f)
 284 #define kmalloc_track_caller kmalloc
 285
 286 #endif /* CONFIG_SLOB */
 287
 288 /* System wide caches */
 289 extern kmem_cache_t     *vm_area_cachep;
 290 extern kmem_cache_t     *names_cachep;
 291 extern kmem_cache_t     *files_cachep;
 292 extern kmem_cache_t     *filp_cachep;
 293 extern kmem_cache_t     *fs_cachep;
 294 extern kmem_cache_t     *sighand_cachep;
 295 extern kmem_cache_t     *bio_cachep;
 296
 297 #endif  /* __KERNEL__ */
 298
 299 #endif  /* _LINUX_SLAB_H */