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