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 /* kmem_cache_t exists for legacy reasons and is not used by code in mm */
  13 typedef struct kmem_cache kmem_cache_t;
  14
  15 #include        <linux/gfp.h>
  16 #include        <linux/init.h>
  17 #include        <linux/types.h>
  18 #include        <asm/page.h>            /* kmalloc_sizes.h needs PAGE_SIZE */
  19 #include        <asm/cache.h>           /* kmalloc_sizes.h needs L1_CACHE_BYTES */
  20
  21 /* flags for kmem_cache_alloc() */
  22 #define SLAB_ATOMIC             GFP_ATOMIC
  23 #define SLAB_KERNEL             GFP_KERNEL
  24 #define SLAB_DMA                GFP_DMA
  25
  26 /* flags to pass to kmem_cache_create().
  27  * The first 3 are only valid when the allocator as been build
  28  * SLAB_DEBUG_SUPPORT.
  29  */
  30 #define SLAB_DEBUG_FREE         0x00000100UL    /* Peform (expensive) checks on free */
  31 #define SLAB_DEBUG_INITIAL      0x00000200UL    /* Call constructor (as verifier) */
  32 #define SLAB_RED_ZONE           0x00000400UL    /* Red zone objs in a cache */
  33 #define SLAB_POISON             0x00000800UL    /* Poison objects */
  34 #define SLAB_HWCACHE_ALIGN      0x00002000UL    /* align objs on a h/w cache lines */
  35 #define SLAB_CACHE_DMA          0x00004000UL    /* use GFP_DMA memory */
  36 #define SLAB_MUST_HWCACHE_ALIGN 0x00008000UL    /* force alignment */
  37 #define SLAB_STORE_USER         0x00010000UL    /* store the last owner for bug hunting */
  38 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL    /* track pages allocated to indicate
  39                                                    what is reclaimable later*/
  40 #define SLAB_PANIC              0x00040000UL    /* panic if kmem_cache_create() fails */
  41 #define SLAB_DESTROY_BY_RCU     0x00080000UL    /* defer freeing pages to RCU */
  42 #define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */
  43
  44 /* flags passed to a constructor func */
  45 #define SLAB_CTOR_CONSTRUCTOR   0x001UL         /* if not set, then deconstructor */
  46 #define SLAB_CTOR_ATOMIC        0x002UL         /* tell constructor it can't sleep */
  47 #define SLAB_CTOR_VERIFY        0x004UL         /* tell constructor it's a verify call */
  48
  49 #ifndef CONFIG_SLOB
  50
  51 /* prototypes */
  52 extern void __init kmem_cache_init(void);
  53
  54 extern struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
  55                         unsigned long,
  56                         void (*)(void *, struct kmem_cache *, unsigned long),
  57                         void (*)(void *, struct kmem_cache *, unsigned long));
  58 extern void kmem_cache_destroy(struct kmem_cache *);
  59 extern int kmem_cache_shrink(struct kmem_cache *);
  60 extern void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
  61 extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
  62 extern void kmem_cache_free(struct kmem_cache *, void *);
  63 extern unsigned int kmem_cache_size(struct kmem_cache *);
  64 extern const char *kmem_cache_name(struct kmem_cache *);
  65
  66 /* Size description struct for general caches. */
  67 struct cache_sizes {
  68         size_t                  cs_size;
  69         struct kmem_cache       *cs_cachep;
  70         struct kmem_cache       *cs_dmacachep;
  71 };
  72 extern struct cache_sizes malloc_sizes[];
  73
  74 extern void *__kmalloc(size_t, gfp_t);
  75
  76 /**
  77  * kmalloc - allocate memory
  78  * @size: how many bytes of memory are required.
  79  * @flags: the type of memory to allocate.
  80  *
  81  * kmalloc is the normal method of allocating memory
  82  * in the kernel.
  83  *
  84  * The @flags argument may be one of:
  85  *
  86  * %GFP_USER - Allocate memory on behalf of user.  May sleep.
  87  *
  88  * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
  89  *
  90  * %GFP_ATOMIC - Allocation will not sleep.
  91  *   For example, use this inside interrupt handlers.
  92  *
  93  * %GFP_HIGHUSER - Allocate pages from high memory.
  94  *
  95  * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
  96  *
  97  * %GFP_NOFS - Do not make any fs calls while trying to get memory.
  98  *
  99  * Also it is possible to set different flags by OR'ing
 100  * in one or more of the following additional @flags:
 101  *
 102  * %__GFP_COLD - Request cache-cold pages instead of
 103  *   trying to return cache-warm pages.
 104  *
 105  * %__GFP_DMA - Request memory from the DMA-capable zone.
 106  *
 107  * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
 108  *
 109  * %__GFP_HIGHMEM - Allocated memory may be from highmem.
 110  *
 111  * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
 112  *   (think twice before using).
 113  *
 114  * %__GFP_NORETRY - If memory is not immediately available,
 115  *   then give up at once.
 116  *
 117  * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
 118  *
 119  * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
 120  */
 121 static inline void *kmalloc(size_t size, gfp_t flags)
 122 {
 123         if (__builtin_constant_p(size)) {
 124                 int i = 0;
 125 #define CACHE(x) \
 126                 if (size <= x) \
 127                         goto found; \
 128                 else \
 129                         i++;
 130 #include "kmalloc_sizes.h"
 131 #undef CACHE
 132                 {
 133                         extern void __you_cannot_kmalloc_that_much(void);
 134                         __you_cannot_kmalloc_that_much();
 135                 }
 136 found:
 137                 return kmem_cache_alloc((flags & GFP_DMA) ?
 138                         malloc_sizes[i].cs_dmacachep :
 139                         malloc_sizes[i].cs_cachep, flags);
 140         }
 141         return __kmalloc(size, flags);
 142 }
 143
 144 /*
 145  * kmalloc_track_caller is a special version of kmalloc that records the
 146  * calling function of the routine calling it for slab leak tracking instead
 147  * of just the calling function (confusing, eh?).
 148  * It's useful when the call to kmalloc comes from a widely-used standard
 149  * allocator where we care about the real place the memory allocation
 150  * request comes from.
 151  */
 152 #ifndef CONFIG_DEBUG_SLAB
 153 #define kmalloc_track_caller(size, flags) \
 154         __kmalloc(size, flags)
 155 #else
 156 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
 157 #define kmalloc_track_caller(size, flags) \
 158         __kmalloc_track_caller(size, flags, __builtin_return_address(0))
 159 #endif
 160
 161 extern void *__kzalloc(size_t, gfp_t);
 162
 163 /**
 164  * kzalloc - allocate memory. The memory is set to zero.
 165  * @size: how many bytes of memory are required.
 166  * @flags: the type of memory to allocate (see kmalloc).
 167  */
 168 static inline void *kzalloc(size_t size, gfp_t flags)
 169 {
 170         if (__builtin_constant_p(size)) {
 171                 int i = 0;
 172 #define CACHE(x) \
 173                 if (size <= x) \
 174                         goto found; \
 175                 else \
 176                         i++;
 177 #include "kmalloc_sizes.h"
 178 #undef CACHE
 179                 {
 180                         extern void __you_cannot_kzalloc_that_much(void);
 181                         __you_cannot_kzalloc_that_much();
 182                 }
 183 found:
 184                 return kmem_cache_zalloc((flags & GFP_DMA) ?
 185                         malloc_sizes[i].cs_dmacachep :
 186                         malloc_sizes[i].cs_cachep, flags);
 187         }
 188         return __kzalloc(size, flags);
 189 }
 190
 191 /**
 192  * kcalloc - allocate memory for an array. The memory is set to zero.
 193  * @n: number of elements.
 194  * @size: element size.
 195  * @flags: the type of memory to allocate.
 196  */
 197 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 198 {
 199         if (n != 0 && size > ULONG_MAX / n)
 200                 return NULL;
 201         return kzalloc(n * size, flags);
 202 }
 203
 204 extern void kfree(const void *);
 205 extern unsigned int ksize(const void *);
 206 extern int slab_is_available(void);
 207
 208 #ifdef CONFIG_NUMA
 209 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
 210 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 211
 212 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 213 {
 214         if (__builtin_constant_p(size)) {
 215                 int i = 0;
 216 #define CACHE(x) \
 217                 if (size <= x) \
 218                         goto found; \
 219                 else \
 220                         i++;
 221 #include "kmalloc_sizes.h"
 222 #undef CACHE
 223                 {
 224                         extern void __you_cannot_kmalloc_that_much(void);
 225                         __you_cannot_kmalloc_that_much();
 226                 }
 227 found:
 228                 return kmem_cache_alloc_node((flags & GFP_DMA) ?
 229                         malloc_sizes[i].cs_dmacachep :
 230                         malloc_sizes[i].cs_cachep, flags, node);
 231         }
 232         return __kmalloc_node(size, flags, node);
 233 }
 234
 235 /*
 236  * kmalloc_node_track_caller is a special version of kmalloc_node that
 237  * records the calling function of the routine calling it for slab leak
 238  * tracking instead of just the calling function (confusing, eh?).
 239  * It's useful when the call to kmalloc_node comes from a widely-used
 240  * standard allocator where we care about the real place the memory
 241  * allocation request comes from.
 242  */
 243 #ifndef CONFIG_DEBUG_SLAB
 244 #define kmalloc_node_track_caller(size, flags, node) \
 245         __kmalloc_node(size, flags, node)
 246 #else
 247 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
 248 #define kmalloc_node_track_caller(size, flags, node) \
 249         __kmalloc_node_track_caller(size, flags, node, \
 250                         __builtin_return_address(0))
 251 #endif
 252 #else /* CONFIG_NUMA */
 253 static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
 254                                         gfp_t flags, int node)
 255 {
 256         return kmem_cache_alloc(cachep, flags);
 257 }
 258 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 259 {
 260         return kmalloc(size, flags);
 261 }
 262
 263 #define kmalloc_node_track_caller(size, flags, node) \
 264         kmalloc_track_caller(size, flags)
 265 #endif
 266
 267 extern int FASTCALL(kmem_cache_reap(int));
 268 extern int FASTCALL(kmem_ptr_validate(struct kmem_cache *cachep, void *ptr));
 269
 270 #else /* CONFIG_SLOB */
 271
 272 /* SLOB allocator routines */
 273
 274 void kmem_cache_init(void);
 275 struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
 276         unsigned long,
 277         void (*)(void *, struct kmem_cache *, unsigned long),
 278         void (*)(void *, struct kmem_cache *, unsigned long));
 279 void kmem_cache_destroy(struct kmem_cache *c);
 280 void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
 281 void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
 282 void kmem_cache_free(struct kmem_cache *c, void *b);
 283 const char *kmem_cache_name(struct kmem_cache *);
 284 void *kmalloc(size_t size, gfp_t flags);
 285 void *__kzalloc(size_t size, gfp_t flags);
 286 void kfree(const void *m);
 287 unsigned int ksize(const void *m);
 288 unsigned int kmem_cache_size(struct kmem_cache *c);
 289
 290 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 291 {
 292         return __kzalloc(n * size, flags);
 293 }
 294
 295 #define kmem_cache_shrink(d) (0)
 296 #define kmem_cache_reap(a)
 297 #define kmem_ptr_validate(a, b) (0)
 298 #define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
 299 #define kmalloc_node(s, f, n) kmalloc(s, f)
 300 #define kzalloc(s, f) __kzalloc(s, f)
 301 #define kmalloc_track_caller kmalloc
 302
 303 #define kmalloc_node_track_caller kmalloc_node
 304
 305 #endif /* CONFIG_SLOB */
 306
 307 #endif  /* __KERNEL__ */
 308
 309 #endif  /* _LINUX_SLAB_H */