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_NOFS               GFP_NOFS
  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 /* flags to pass to kmem_cache_create().
  29  * The first 3 are only valid when the allocator as been build
  30  * SLAB_DEBUG_SUPPORT.
  31  */
  32 #define SLAB_DEBUG_FREE         0x00000100UL    /* Peform (expensive) checks on free */
  33 #define SLAB_DEBUG_INITIAL      0x00000200UL    /* Call constructor (as verifier) */
  34 #define SLAB_RED_ZONE           0x00000400UL    /* Red zone objs in a cache */
  35 #define SLAB_POISON             0x00000800UL    /* Poison objects */
  36 #define SLAB_HWCACHE_ALIGN      0x00002000UL    /* align objs on a h/w cache lines */
  37 #define SLAB_CACHE_DMA          0x00004000UL    /* use GFP_DMA memory */
  38 #define SLAB_MUST_HWCACHE_ALIGN 0x00008000UL    /* force alignment */
  39 #define SLAB_STORE_USER         0x00010000UL    /* store the last owner for bug hunting */
  40 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL    /* track pages allocated to indicate
  41                                                    what is reclaimable later*/
  42 #define SLAB_PANIC              0x00040000UL    /* panic if kmem_cache_create() fails */
  43 #define SLAB_DESTROY_BY_RCU     0x00080000UL    /* defer freeing pages to RCU */
  44 #define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */
  45
  46 /* flags passed to a constructor func */
  47 #define SLAB_CTOR_CONSTRUCTOR   0x001UL         /* if not set, then deconstructor */
  48 #define SLAB_CTOR_ATOMIC        0x002UL         /* tell constructor it can't sleep */
  49 #define SLAB_CTOR_VERIFY        0x004UL         /* tell constructor it's a verify call */
  50
  51 #ifndef CONFIG_SLOB
  52
  53 /* prototypes */
  54 extern void __init kmem_cache_init(void);
  55
  56 extern struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
  57                         unsigned long,
  58                         void (*)(void *, struct kmem_cache *, unsigned long),
  59                         void (*)(void *, struct kmem_cache *, unsigned long));
  60 extern void kmem_cache_destroy(struct kmem_cache *);
  61 extern int kmem_cache_shrink(struct kmem_cache *);
  62 extern void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
  63 extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
  64 extern void kmem_cache_free(struct kmem_cache *, void *);
  65 extern unsigned int kmem_cache_size(struct kmem_cache *);
  66 extern const char *kmem_cache_name(struct kmem_cache *);
  67
  68 /* Size description struct for general caches. */
  69 struct cache_sizes {
  70         size_t                  cs_size;
  71         struct kmem_cache       *cs_cachep;
  72         struct kmem_cache       *cs_dmacachep;
  73 };
  74 extern struct cache_sizes malloc_sizes[];
  75
  76 extern void *__kmalloc(size_t, gfp_t);
  77
  78 /**
  79  * kmalloc - allocate memory
  80  * @size: how many bytes of memory are required.
  81  * @flags: the type of memory to allocate.
  82  *
  83  * kmalloc is the normal method of allocating memory
  84  * in the kernel.
  85  *
  86  * The @flags argument may be one of:
  87  *
  88  * %GFP_USER - Allocate memory on behalf of user.  May sleep.
  89  *
  90  * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
  91  *
  92  * %GFP_ATOMIC - Allocation will not sleep.
  93  *   For example, use this inside interrupt handlers.
  94  *
  95  * %GFP_HIGHUSER - Allocate pages from high memory.
  96  *
  97  * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
  98  *
  99  * %GFP_NOFS - Do not make any fs calls while trying to get memory.
 100  *
 101  * Also it is possible to set different flags by OR'ing
 102  * in one or more of the following additional @flags:
 103  *
 104  * %__GFP_COLD - Request cache-cold pages instead of
 105  *   trying to return cache-warm pages.
 106  *
 107  * %__GFP_DMA - Request memory from the DMA-capable zone.
 108  *
 109  * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
 110  *
 111  * %__GFP_HIGHMEM - Allocated memory may be from highmem.
 112  *
 113  * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
 114  *   (think twice before using).
 115  *
 116  * %__GFP_NORETRY - If memory is not immediately available,
 117  *   then give up at once.
 118  *
 119  * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
 120  *
 121  * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
 122  */
 123 static inline void *kmalloc(size_t size, gfp_t flags)
 124 {
 125         if (__builtin_constant_p(size)) {
 126                 int i = 0;
 127 #define CACHE(x) \
 128                 if (size <= x) \
 129                         goto found; \
 130                 else \
 131                         i++;
 132 #include "kmalloc_sizes.h"
 133 #undef CACHE
 134                 {
 135                         extern void __you_cannot_kmalloc_that_much(void);
 136                         __you_cannot_kmalloc_that_much();
 137                 }
 138 found:
 139                 return kmem_cache_alloc((flags & GFP_DMA) ?
 140                         malloc_sizes[i].cs_dmacachep :
 141                         malloc_sizes[i].cs_cachep, flags);
 142         }
 143         return __kmalloc(size, flags);
 144 }
 145
 146 /*
 147  * kmalloc_track_caller is a special version of kmalloc that records the
 148  * calling function of the routine calling it for slab leak tracking instead
 149  * of just the calling function (confusing, eh?).
 150  * It's useful when the call to kmalloc comes from a widely-used standard
 151  * allocator where we care about the real place the memory allocation
 152  * request comes from.
 153  */
 154 #ifndef CONFIG_DEBUG_SLAB
 155 #define kmalloc_track_caller(size, flags) \
 156         __kmalloc(size, flags)
 157 #else
 158 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
 159 #define kmalloc_track_caller(size, flags) \
 160         __kmalloc_track_caller(size, flags, __builtin_return_address(0))
 161 #endif
 162
 163 extern void *__kzalloc(size_t, gfp_t);
 164
 165 /**
 166  * kzalloc - allocate memory. The memory is set to zero.
 167  * @size: how many bytes of memory are required.
 168  * @flags: the type of memory to allocate (see kmalloc).
 169  */
 170 static inline void *kzalloc(size_t size, gfp_t flags)
 171 {
 172         if (__builtin_constant_p(size)) {
 173                 int i = 0;
 174 #define CACHE(x) \
 175                 if (size <= x) \
 176                         goto found; \
 177                 else \
 178                         i++;
 179 #include "kmalloc_sizes.h"
 180 #undef CACHE
 181                 {
 182                         extern void __you_cannot_kzalloc_that_much(void);
 183                         __you_cannot_kzalloc_that_much();
 184                 }
 185 found:
 186                 return kmem_cache_zalloc((flags & GFP_DMA) ?
 187                         malloc_sizes[i].cs_dmacachep :
 188                         malloc_sizes[i].cs_cachep, flags);
 189         }
 190         return __kzalloc(size, flags);
 191 }
 192
 193 /**
 194  * kcalloc - allocate memory for an array. The memory is set to zero.
 195  * @n: number of elements.
 196  * @size: element size.
 197  * @flags: the type of memory to allocate.
 198  */
 199 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 200 {
 201         if (n != 0 && size > ULONG_MAX / n)
 202                 return NULL;
 203         return kzalloc(n * size, flags);
 204 }
 205
 206 extern void kfree(const void *);
 207 extern unsigned int ksize(const void *);
 208 extern int slab_is_available(void);
 209
 210 #ifdef CONFIG_NUMA
 211 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
 212 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 213
 214 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 215 {
 216         if (__builtin_constant_p(size)) {
 217                 int i = 0;
 218 #define CACHE(x) \
 219                 if (size <= x) \
 220                         goto found; \
 221                 else \
 222                         i++;
 223 #include "kmalloc_sizes.h"
 224 #undef CACHE
 225                 {
 226                         extern void __you_cannot_kmalloc_that_much(void);
 227                         __you_cannot_kmalloc_that_much();
 228                 }
 229 found:
 230                 return kmem_cache_alloc_node((flags & GFP_DMA) ?
 231                         malloc_sizes[i].cs_dmacachep :
 232                         malloc_sizes[i].cs_cachep, flags, node);
 233         }
 234         return __kmalloc_node(size, flags, node);
 235 }
 236
 237 /*
 238  * kmalloc_node_track_caller is a special version of kmalloc_node that
 239  * records the calling function of the routine calling it for slab leak
 240  * tracking instead of just the calling function (confusing, eh?).
 241  * It's useful when the call to kmalloc_node comes from a widely-used
 242  * standard allocator where we care about the real place the memory
 243  * allocation request comes from.
 244  */
 245 #ifndef CONFIG_DEBUG_SLAB
 246 #define kmalloc_node_track_caller(size, flags, node) \
 247         __kmalloc_node(size, flags, node)
 248 #else
 249 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
 250 #define kmalloc_node_track_caller(size, flags, node) \
 251         __kmalloc_node_track_caller(size, flags, node, \
 252                         __builtin_return_address(0))
 253 #endif
 254 #else /* CONFIG_NUMA */
 255 static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
 256                                         gfp_t flags, int node)
 257 {
 258         return kmem_cache_alloc(cachep, flags);
 259 }
 260 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 261 {
 262         return kmalloc(size, flags);
 263 }
 264
 265 #define kmalloc_node_track_caller(size, flags, node) \
 266         kmalloc_track_caller(size, flags)
 267 #endif
 268
 269 extern int FASTCALL(kmem_cache_reap(int));
 270 extern int FASTCALL(kmem_ptr_validate(struct kmem_cache *cachep, void *ptr));
 271
 272 #else /* CONFIG_SLOB */
 273
 274 /* SLOB allocator routines */
 275
 276 void kmem_cache_init(void);
 277 struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
 278         unsigned long,
 279         void (*)(void *, struct kmem_cache *, unsigned long),
 280         void (*)(void *, struct kmem_cache *, unsigned long));
 281 void kmem_cache_destroy(struct kmem_cache *c);
 282 void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
 283 void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
 284 void kmem_cache_free(struct kmem_cache *c, void *b);
 285 const char *kmem_cache_name(struct kmem_cache *);
 286 void *kmalloc(size_t size, gfp_t flags);
 287 void *__kzalloc(size_t size, gfp_t flags);
 288 void kfree(const void *m);
 289 unsigned int ksize(const void *m);
 290 unsigned int kmem_cache_size(struct kmem_cache *c);
 291
 292 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 293 {
 294         return __kzalloc(n * size, flags);
 295 }
 296
 297 #define kmem_cache_shrink(d) (0)
 298 #define kmem_cache_reap(a)
 299 #define kmem_ptr_validate(a, b) (0)
 300 #define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
 301 #define kmalloc_node(s, f, n) kmalloc(s, f)
 302 #define kzalloc(s, f) __kzalloc(s, f)
 303 #define kmalloc_track_caller kmalloc
 304
 305 #define kmalloc_node_track_caller kmalloc_node
 306
 307 #endif /* CONFIG_SLOB */
 308
 309 #endif  /* __KERNEL__ */
 310
 311 #endif  /* _LINUX_SLAB_H */