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 #ifdef __KERNEL__
  11
  12 #include <linux/gfp.h>
  13 #include <linux/init.h>
  14 #include <linux/types.h>
  15 #include <asm/page.h>           /* kmalloc_sizes.h needs PAGE_SIZE */
  16 #include <asm/cache.h>          /* kmalloc_sizes.h needs L1_CACHE_BYTES */
  17 #include <linux/compiler.h>
  18
  19 /* kmem_cache_t exists for legacy reasons and is not used by code in mm */
  20 typedef struct kmem_cache kmem_cache_t __deprecated;
  21
  22 /* flags to pass to kmem_cache_create().
  23  * The first 3 are only valid when the allocator as been build
  24  * SLAB_DEBUG_SUPPORT.
  25  */
  26 #define SLAB_DEBUG_FREE         0x00000100UL    /* Peform (expensive) checks on free */
  27 #define SLAB_DEBUG_INITIAL      0x00000200UL    /* Call constructor (as verifier) */
  28 #define SLAB_RED_ZONE           0x00000400UL    /* Red zone objs in a cache */
  29 #define SLAB_POISON             0x00000800UL    /* Poison objects */
  30 #define SLAB_HWCACHE_ALIGN      0x00002000UL    /* align objs on a h/w cache lines */
  31 #define SLAB_CACHE_DMA          0x00004000UL    /* use GFP_DMA memory */
  32 #define SLAB_MUST_HWCACHE_ALIGN 0x00008000UL    /* force alignment */
  33 #define SLAB_STORE_USER         0x00010000UL    /* store the last owner for bug hunting */
  34 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL    /* track pages allocated to indicate
  35                                                    what is reclaimable later*/
  36 #define SLAB_PANIC              0x00040000UL    /* panic if kmem_cache_create() fails */
  37 #define SLAB_DESTROY_BY_RCU     0x00080000UL    /* defer freeing pages to RCU */
  38 #define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */
  39
  40 /* flags passed to a constructor func */
  41 #define SLAB_CTOR_CONSTRUCTOR   0x001UL         /* if not set, then deconstructor */
  42 #define SLAB_CTOR_ATOMIC        0x002UL         /* tell constructor it can't sleep */
  43 #define SLAB_CTOR_VERIFY        0x004UL         /* tell constructor it's a verify call */
  44
  45 #ifndef CONFIG_SLOB
  46
  47 /* prototypes */
  48 extern void __init kmem_cache_init(void);
  49
  50 extern struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
  51                         unsigned long,
  52                         void (*)(void *, struct kmem_cache *, unsigned long),
  53                         void (*)(void *, struct kmem_cache *, unsigned long));
  54 extern void kmem_cache_destroy(struct kmem_cache *);
  55 extern int kmem_cache_shrink(struct kmem_cache *);
  56 extern void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
  57 extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
  58 extern void kmem_cache_free(struct kmem_cache *, void *);
  59 extern unsigned int kmem_cache_size(struct kmem_cache *);
  60 extern const char *kmem_cache_name(struct kmem_cache *);
  61
  62 /* Size description struct for general caches. */
  63 struct cache_sizes {
  64         size_t                  cs_size;
  65         struct kmem_cache       *cs_cachep;
  66         struct kmem_cache       *cs_dmacachep;
  67 };
  68 extern struct cache_sizes malloc_sizes[];
  69
  70 extern void *__kmalloc(size_t, gfp_t);
  71
  72 /**
  73  * kmalloc - allocate memory
  74  * @size: how many bytes of memory are required.
  75  * @flags: the type of memory to allocate.
  76  *
  77  * kmalloc is the normal method of allocating memory
  78  * in the kernel.
  79  *
  80  * The @flags argument may be one of:
  81  *
  82  * %GFP_USER - Allocate memory on behalf of user.  May sleep.
  83  *
  84  * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
  85  *
  86  * %GFP_ATOMIC - Allocation will not sleep.
  87  *   For example, use this inside interrupt handlers.
  88  *
  89  * %GFP_HIGHUSER - Allocate pages from high memory.
  90  *
  91  * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
  92  *
  93  * %GFP_NOFS - Do not make any fs calls while trying to get memory.
  94  *
  95  * Also it is possible to set different flags by OR'ing
  96  * in one or more of the following additional @flags:
  97  *
  98  * %__GFP_COLD - Request cache-cold pages instead of
  99  *   trying to return cache-warm pages.
 100  *
 101  * %__GFP_DMA - Request memory from the DMA-capable zone.
 102  *
 103  * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
 104  *
 105  * %__GFP_HIGHMEM - Allocated memory may be from highmem.
 106  *
 107  * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
 108  *   (think twice before using).
 109  *
 110  * %__GFP_NORETRY - If memory is not immediately available,
 111  *   then give up at once.
 112  *
 113  * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
 114  *
 115  * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
 116  */
 117 static inline void *kmalloc(size_t size, gfp_t flags)
 118 {
 119         if (__builtin_constant_p(size)) {
 120                 int i = 0;
 121 #define CACHE(x) \
 122                 if (size <= x) \
 123                         goto found; \
 124                 else \
 125                         i++;
 126 #include "kmalloc_sizes.h"
 127 #undef CACHE
 128                 {
 129                         extern void __you_cannot_kmalloc_that_much(void);
 130                         __you_cannot_kmalloc_that_much();
 131                 }
 132 found:
 133                 return kmem_cache_alloc((flags & GFP_DMA) ?
 134                         malloc_sizes[i].cs_dmacachep :
 135                         malloc_sizes[i].cs_cachep, flags);
 136         }
 137         return __kmalloc(size, flags);
 138 }
 139
 140 /*
 141  * kmalloc_track_caller is a special version of kmalloc that records the
 142  * calling function of the routine calling it for slab leak tracking instead
 143  * of just the calling function (confusing, eh?).
 144  * It's useful when the call to kmalloc comes from a widely-used standard
 145  * allocator where we care about the real place the memory allocation
 146  * request comes from.
 147  */
 148 #ifndef CONFIG_DEBUG_SLAB
 149 #define kmalloc_track_caller(size, flags) \
 150         __kmalloc(size, flags)
 151 #else
 152 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
 153 #define kmalloc_track_caller(size, flags) \
 154         __kmalloc_track_caller(size, flags, __builtin_return_address(0))
 155 #endif
 156
 157 extern void *__kzalloc(size_t, gfp_t);
 158
 159 /**
 160  * kzalloc - allocate memory. The memory is set to zero.
 161  * @size: how many bytes of memory are required.
 162  * @flags: the type of memory to allocate (see kmalloc).
 163  */
 164 static inline void *kzalloc(size_t size, gfp_t flags)
 165 {
 166         if (__builtin_constant_p(size)) {
 167                 int i = 0;
 168 #define CACHE(x) \
 169                 if (size <= x) \
 170                         goto found; \
 171                 else \
 172                         i++;
 173 #include "kmalloc_sizes.h"
 174 #undef CACHE
 175                 {
 176                         extern void __you_cannot_kzalloc_that_much(void);
 177                         __you_cannot_kzalloc_that_much();
 178                 }
 179 found:
 180                 return kmem_cache_zalloc((flags & GFP_DMA) ?
 181                         malloc_sizes[i].cs_dmacachep :
 182                         malloc_sizes[i].cs_cachep, flags);
 183         }
 184         return __kzalloc(size, flags);
 185 }
 186
 187 /**
 188  * kcalloc - allocate memory for an array. The memory is set to zero.
 189  * @n: number of elements.
 190  * @size: element size.
 191  * @flags: the type of memory to allocate.
 192  */
 193 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 194 {
 195         if (n != 0 && size > ULONG_MAX / n)
 196                 return NULL;
 197         return kzalloc(n * size, flags);
 198 }
 199
 200 extern void kfree(const void *);
 201 extern unsigned int ksize(const void *);
 202 extern int slab_is_available(void);
 203
 204 #ifdef CONFIG_NUMA
 205 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
 206 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 207
 208 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 209 {
 210         if (__builtin_constant_p(size)) {
 211                 int i = 0;
 212 #define CACHE(x) \
 213                 if (size <= x) \
 214                         goto found; \
 215                 else \
 216                         i++;
 217 #include "kmalloc_sizes.h"
 218 #undef CACHE
 219                 {
 220                         extern void __you_cannot_kmalloc_that_much(void);
 221                         __you_cannot_kmalloc_that_much();
 222                 }
 223 found:
 224                 return kmem_cache_alloc_node((flags & GFP_DMA) ?
 225                         malloc_sizes[i].cs_dmacachep :
 226                         malloc_sizes[i].cs_cachep, flags, node);
 227         }
 228         return __kmalloc_node(size, flags, node);
 229 }
 230
 231 /*
 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.
 238  */
 239 #ifndef CONFIG_DEBUG_SLAB
 240 #define kmalloc_node_track_caller(size, flags, node) \
 241         __kmalloc_node(size, flags, node)
 242 #else
 243 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
 244 #define kmalloc_node_track_caller(size, flags, node) \
 245         __kmalloc_node_track_caller(size, flags, node, \
 246                         __builtin_return_address(0))
 247 #endif
 248 #else /* CONFIG_NUMA */
 249 static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
 250                                         gfp_t flags, int node)
 251 {
 252         return kmem_cache_alloc(cachep, flags);
 253 }
 254 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 255 {
 256         return kmalloc(size, flags);
 257 }
 258
 259 #define kmalloc_node_track_caller(size, flags, node) \
 260         kmalloc_track_caller(size, flags)
 261 #endif
 262
 263 extern int FASTCALL(kmem_cache_reap(int));
 264 extern int FASTCALL(kmem_ptr_validate(struct kmem_cache *cachep, void *ptr));
 265
 266 #else /* CONFIG_SLOB */
 267
 268 /* SLOB allocator routines */
 269
 270 void kmem_cache_init(void);
 271 struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
 272         unsigned long,
 273         void (*)(void *, struct kmem_cache *, unsigned long),
 274         void (*)(void *, struct kmem_cache *, unsigned long));
 275 void kmem_cache_destroy(struct kmem_cache *c);
 276 void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
 277 void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
 278 void kmem_cache_free(struct kmem_cache *c, void *b);
 279 const char *kmem_cache_name(struct kmem_cache *);
 280 void *kmalloc(size_t size, gfp_t flags);
 281 void *__kzalloc(size_t size, gfp_t flags);
 282 void kfree(const void *m);
 283 unsigned int ksize(const void *m);
 284 unsigned int kmem_cache_size(struct kmem_cache *c);
 285
 286 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 287 {
 288         return __kzalloc(n * size, flags);
 289 }
 290
 291 #define kmem_cache_shrink(d) (0)
 292 #define kmem_cache_reap(a)
 293 #define kmem_ptr_validate(a, b) (0)
 294 #define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
 295 #define kmalloc_node(s, f, n) kmalloc(s, f)
 296 #define kzalloc(s, f) __kzalloc(s, f)
 297 #define kmalloc_track_caller kmalloc
 298
 299 #define kmalloc_node_track_caller kmalloc_node
 300
 301 #endif /* CONFIG_SLOB */
 302
 303 #endif  /* __KERNEL__ */
 304
 305 #endif  /* _LINUX_SLAB_H */