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_NOIO               GFP_NOIO
  24 #define SLAB_ATOMIC             GFP_ATOMIC
  25 #define SLAB_USER               GFP_USER
  26 #define SLAB_KERNEL             GFP_KERNEL
  27 #define SLAB_DMA                GFP_DMA
  28
  29 #define SLAB_LEVEL_MASK         GFP_LEVEL_MASK
  30
  31 #define SLAB_NO_GROW            __GFP_NO_GROW   /* don't grow a cache */
  32
  33 /* flags to pass to kmem_cache_create().
  34  * The first 3 are only valid when the allocator as been build
  35  * SLAB_DEBUG_SUPPORT.
  36  */
  37 #define SLAB_DEBUG_FREE         0x00000100UL    /* Peform (expensive) checks on free */
  38 #define SLAB_DEBUG_INITIAL      0x00000200UL    /* Call constructor (as verifier) */
  39 #define SLAB_RED_ZONE           0x00000400UL    /* Red zone objs in a cache */
  40 #define SLAB_POISON             0x00000800UL    /* Poison objects */
  41 #define SLAB_HWCACHE_ALIGN      0x00002000UL    /* align objs on a h/w cache lines */
  42 #define SLAB_CACHE_DMA          0x00004000UL    /* use GFP_DMA memory */
  43 #define SLAB_MUST_HWCACHE_ALIGN 0x00008000UL    /* force alignment */
  44 #define SLAB_STORE_USER         0x00010000UL    /* store the last owner for bug hunting */
  45 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL    /* track pages allocated to indicate
  46                                                    what is reclaimable later*/
  47 #define SLAB_PANIC              0x00040000UL    /* panic if kmem_cache_create() fails */
  48 #define SLAB_DESTROY_BY_RCU     0x00080000UL    /* defer freeing pages to RCU */
  49 #define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */
  50
  51 /* flags passed to a constructor func */
  52 #define SLAB_CTOR_CONSTRUCTOR   0x001UL         /* if not set, then deconstructor */
  53 #define SLAB_CTOR_ATOMIC        0x002UL         /* tell constructor it can't sleep */
  54 #define SLAB_CTOR_VERIFY        0x004UL         /* tell constructor it's a verify call */
  55
  56 #ifndef CONFIG_SLOB
  57
  58 /* prototypes */
  59 extern void __init kmem_cache_init(void);
  60
  61 extern struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
  62                         unsigned long,
  63                         void (*)(void *, struct kmem_cache *, unsigned long),
  64                         void (*)(void *, struct kmem_cache *, unsigned long));
  65 extern void kmem_cache_destroy(struct kmem_cache *);
  66 extern int kmem_cache_shrink(struct kmem_cache *);
  67 extern void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
  68 extern void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
  69 extern void kmem_cache_free(struct kmem_cache *, void *);
  70 extern unsigned int kmem_cache_size(struct kmem_cache *);
  71 extern const char *kmem_cache_name(struct kmem_cache *);
  72
  73 /* Size description struct for general caches. */
  74 struct cache_sizes {
  75         size_t                  cs_size;
  76         struct kmem_cache       *cs_cachep;
  77         struct kmem_cache       *cs_dmacachep;
  78 };
  79 extern struct cache_sizes malloc_sizes[];
  80
  81 extern void *__kmalloc(size_t, gfp_t);
  82
  83 /**
  84  * kmalloc - allocate memory
  85  * @size: how many bytes of memory are required.
  86  * @flags: the type of memory to allocate.
  87  *
  88  * kmalloc is the normal method of allocating memory
  89  * in the kernel.
  90  *
  91  * The @flags argument may be one of:
  92  *
  93  * %GFP_USER - Allocate memory on behalf of user.  May sleep.
  94  *
  95  * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
  96  *
  97  * %GFP_ATOMIC - Allocation will not sleep.
  98  *   For example, use this inside interrupt handlers.
  99  *
 100  * %GFP_HIGHUSER - Allocate pages from high memory.
 101  *
 102  * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
 103  *
 104  * %GFP_NOFS - Do not make any fs calls while trying to get memory.
 105  *
 106  * Also it is possible to set different flags by OR'ing
 107  * in one or more of the following additional @flags:
 108  *
 109  * %__GFP_COLD - Request cache-cold pages instead of
 110  *   trying to return cache-warm pages.
 111  *
 112  * %__GFP_DMA - Request memory from the DMA-capable zone.
 113  *
 114  * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
 115  *
 116  * %__GFP_HIGHMEM - Allocated memory may be from highmem.
 117  *
 118  * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
 119  *   (think twice before using).
 120  *
 121  * %__GFP_NORETRY - If memory is not immediately available,
 122  *   then give up at once.
 123  *
 124  * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
 125  *
 126  * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
 127  */
 128 static inline void *kmalloc(size_t size, gfp_t flags)
 129 {
 130         if (__builtin_constant_p(size)) {
 131                 int i = 0;
 132 #define CACHE(x) \
 133                 if (size <= x) \
 134                         goto found; \
 135                 else \
 136                         i++;
 137 #include "kmalloc_sizes.h"
 138 #undef CACHE
 139                 {
 140                         extern void __you_cannot_kmalloc_that_much(void);
 141                         __you_cannot_kmalloc_that_much();
 142                 }
 143 found:
 144                 return kmem_cache_alloc((flags & GFP_DMA) ?
 145                         malloc_sizes[i].cs_dmacachep :
 146                         malloc_sizes[i].cs_cachep, flags);
 147         }
 148         return __kmalloc(size, flags);
 149 }
 150
 151 /*
 152  * kmalloc_track_caller is a special version of kmalloc that records the
 153  * calling function of the routine calling it for slab leak tracking instead
 154  * of just the calling function (confusing, eh?).
 155  * It's useful when the call to kmalloc comes from a widely-used standard
 156  * allocator where we care about the real place the memory allocation
 157  * request comes from.
 158  */
 159 #ifndef CONFIG_DEBUG_SLAB
 160 #define kmalloc_track_caller(size, flags) \
 161         __kmalloc(size, flags)
 162 #else
 163 extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
 164 #define kmalloc_track_caller(size, flags) \
 165         __kmalloc_track_caller(size, flags, __builtin_return_address(0))
 166 #endif
 167
 168 extern void *__kzalloc(size_t, gfp_t);
 169
 170 /**
 171  * kzalloc - allocate memory. The memory is set to zero.
 172  * @size: how many bytes of memory are required.
 173  * @flags: the type of memory to allocate (see kmalloc).
 174  */
 175 static inline void *kzalloc(size_t size, gfp_t flags)
 176 {
 177         if (__builtin_constant_p(size)) {
 178                 int i = 0;
 179 #define CACHE(x) \
 180                 if (size <= x) \
 181                         goto found; \
 182                 else \
 183                         i++;
 184 #include "kmalloc_sizes.h"
 185 #undef CACHE
 186                 {
 187                         extern void __you_cannot_kzalloc_that_much(void);
 188                         __you_cannot_kzalloc_that_much();
 189                 }
 190 found:
 191                 return kmem_cache_zalloc((flags & GFP_DMA) ?
 192                         malloc_sizes[i].cs_dmacachep :
 193                         malloc_sizes[i].cs_cachep, flags);
 194         }
 195         return __kzalloc(size, flags);
 196 }
 197
 198 /**
 199  * kcalloc - allocate memory for an array. The memory is set to zero.
 200  * @n: number of elements.
 201  * @size: element size.
 202  * @flags: the type of memory to allocate.
 203  */
 204 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 205 {
 206         if (n != 0 && size > ULONG_MAX / n)
 207                 return NULL;
 208         return kzalloc(n * size, flags);
 209 }
 210
 211 extern void kfree(const void *);
 212 extern unsigned int ksize(const void *);
 213 extern int slab_is_available(void);
 214
 215 #ifdef CONFIG_NUMA
 216 extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
 217 extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
 218
 219 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 220 {
 221         if (__builtin_constant_p(size)) {
 222                 int i = 0;
 223 #define CACHE(x) \
 224                 if (size <= x) \
 225                         goto found; \
 226                 else \
 227                         i++;
 228 #include "kmalloc_sizes.h"
 229 #undef CACHE
 230                 {
 231                         extern void __you_cannot_kmalloc_that_much(void);
 232                         __you_cannot_kmalloc_that_much();
 233                 }
 234 found:
 235                 return kmem_cache_alloc_node((flags & GFP_DMA) ?
 236                         malloc_sizes[i].cs_dmacachep :
 237                         malloc_sizes[i].cs_cachep, flags, node);
 238         }
 239         return __kmalloc_node(size, flags, node);
 240 }
 241
 242 /*
 243  * kmalloc_node_track_caller is a special version of kmalloc_node that
 244  * records the calling function of the routine calling it for slab leak
 245  * tracking instead of just the calling function (confusing, eh?).
 246  * It's useful when the call to kmalloc_node comes from a widely-used
 247  * standard allocator where we care about the real place the memory
 248  * allocation request comes from.
 249  */
 250 #ifndef CONFIG_DEBUG_SLAB
 251 #define kmalloc_node_track_caller(size, flags, node) \
 252         __kmalloc_node(size, flags, node)
 253 #else
 254 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
 255 #define kmalloc_node_track_caller(size, flags, node) \
 256         __kmalloc_node_track_caller(size, flags, node, \
 257                         __builtin_return_address(0))
 258 #endif
 259 #else /* CONFIG_NUMA */
 260 static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
 261                                         gfp_t flags, int node)
 262 {
 263         return kmem_cache_alloc(cachep, flags);
 264 }
 265 static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 266 {
 267         return kmalloc(size, flags);
 268 }
 269
 270 #define kmalloc_node_track_caller(size, flags, node) \
 271         kmalloc_track_caller(size, flags)
 272 #endif
 273
 274 extern int FASTCALL(kmem_cache_reap(int));
 275 extern int FASTCALL(kmem_ptr_validate(struct kmem_cache *cachep, void *ptr));
 276
 277 #else /* CONFIG_SLOB */
 278
 279 /* SLOB allocator routines */
 280
 281 void kmem_cache_init(void);
 282 struct kmem_cache *kmem_cache_create(const char *c, size_t, size_t,
 283         unsigned long,
 284         void (*)(void *, struct kmem_cache *, unsigned long),
 285         void (*)(void *, struct kmem_cache *, unsigned long));
 286 void kmem_cache_destroy(struct kmem_cache *c);
 287 void *kmem_cache_alloc(struct kmem_cache *c, gfp_t flags);
 288 void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
 289 void kmem_cache_free(struct kmem_cache *c, void *b);
 290 const char *kmem_cache_name(struct kmem_cache *);
 291 void *kmalloc(size_t size, gfp_t flags);
 292 void *__kzalloc(size_t size, gfp_t flags);
 293 void kfree(const void *m);
 294 unsigned int ksize(const void *m);
 295 unsigned int kmem_cache_size(struct kmem_cache *c);
 296
 297 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 298 {
 299         return __kzalloc(n * size, flags);
 300 }
 301
 302 #define kmem_cache_shrink(d) (0)
 303 #define kmem_cache_reap(a)
 304 #define kmem_ptr_validate(a, b) (0)
 305 #define kmem_cache_alloc_node(c, f, n) kmem_cache_alloc(c, f)
 306 #define kmalloc_node(s, f, n) kmalloc(s, f)
 307 #define kzalloc(s, f) __kzalloc(s, f)
 308 #define kmalloc_track_caller kmalloc
 309
 310 #define kmalloc_node_track_caller kmalloc_node
 311
 312 #endif /* CONFIG_SLOB */
 313
 314 #endif  /* __KERNEL__ */
 315
 316 #endif  /* _LINUX_SLAB_H */