diff options
Diffstat (limited to 'include/linux/slab.h')
| -rw-r--r-- | include/linux/slab.h | 153 |
1 files changed, 88 insertions, 65 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index cebcd3833c76..d859354b9e51 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -14,8 +14,6 @@ #include <linux/gfp.h> #include <linux/types.h> -typedef struct kmem_cache kmem_cache_t __deprecated; - /* * Flags to pass to kmem_cache_create(). * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set. @@ -33,6 +31,19 @@ typedef struct kmem_cache kmem_cache_t __deprecated; #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */ /* + * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. + * + * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault. + * + * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can. + * Both make kfree a no-op. + */ +#define ZERO_SIZE_PTR ((void *)16) + +#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \ + (unsigned long)ZERO_SIZE_PTR) + +/* * struct kmem_cache related prototypes */ void __init kmem_cache_init(void); @@ -40,12 +51,9 @@ int slab_is_available(void); struct kmem_cache *kmem_cache_create(const char *, size_t, size_t, unsigned long, - void (*)(void *, struct kmem_cache *, unsigned long), void (*)(void *, struct kmem_cache *, unsigned long)); void kmem_cache_destroy(struct kmem_cache *); int kmem_cache_shrink(struct kmem_cache *); -void *kmem_cache_alloc(struct kmem_cache *, gfp_t); -void *kmem_cache_zalloc(struct kmem_cache *, gfp_t); void kmem_cache_free(struct kmem_cache *, void *); unsigned int kmem_cache_size(struct kmem_cache *); const char *kmem_cache_name(struct kmem_cache *); @@ -61,17 +69,7 @@ int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr); */ #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\ sizeof(struct __struct), __alignof__(struct __struct),\ - (__flags), NULL, NULL) - -#ifdef CONFIG_NUMA -extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node); -#else -static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep, - gfp_t flags, int node) -{ - return kmem_cache_alloc(cachep, flags); -} -#endif + (__flags), NULL) /* * The largest kmalloc size supported by the slab allocators is @@ -91,59 +89,50 @@ static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep, /* * Common kmalloc functions provided by all allocators */ -void *__kmalloc(size_t, gfp_t); -void *__kzalloc(size_t, gfp_t); void * __must_check krealloc(const void *, size_t, gfp_t); void kfree(const void *); size_t ksize(const void *); -/** - * kcalloc - allocate memory for an array. The memory is set to zero. - * @n: number of elements. - * @size: element size. - * @flags: the type of memory to allocate. - */ -static inline void *kcalloc(size_t n, size_t size, gfp_t flags) -{ - if (n != 0 && size > ULONG_MAX / n) - return NULL; - return __kzalloc(n * size, flags); -} - /* * Allocator specific definitions. These are mainly used to establish optimized - * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by selecting - * the appropriate general cache at compile time. + * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by + * selecting the appropriate general cache at compile time. + * + * Allocators must define at least: + * + * kmem_cache_alloc() + * __kmalloc() + * kmalloc() + * + * Those wishing to support NUMA must also define: + * + * kmem_cache_alloc_node() + * kmalloc_node() + * + * See each allocator definition file for additional comments and + * implementation notes. */ - -#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB) #ifdef CONFIG_SLUB #include <linux/slub_def.h> +#elif defined(CONFIG_SLOB) +#include <linux/slob_def.h> #else #include <linux/slab_def.h> -#endif /* !CONFIG_SLUB */ -#else - -/* - * Fallback definitions for an allocator not wanting to provide - * its own optimized kmalloc definitions (like SLOB). - */ +#endif /** - * kmalloc - allocate memory - * @size: how many bytes of memory are required. + * kcalloc - allocate memory for an array. The memory is set to zero. + * @n: number of elements. + * @size: element size. * @flags: the type of memory to allocate. * - * kmalloc is the normal method of allocating memory - * in the kernel. - * * The @flags argument may be one of: * * %GFP_USER - Allocate memory on behalf of user. May sleep. * * %GFP_KERNEL - Allocate normal kernel ram. May sleep. * - * %GFP_ATOMIC - Allocation will not sleep. + * %GFP_ATOMIC - Allocation will not sleep. May use emergency pools. * For example, use this inside interrupt handlers. * * %GFP_HIGHUSER - Allocate pages from high memory. @@ -152,18 +141,22 @@ static inline void *kcalloc(size_t n, size_t size, gfp_t flags) * * %GFP_NOFS - Do not make any fs calls while trying to get memory. * + * %GFP_NOWAIT - Allocation will not sleep. + * + * %GFP_THISNODE - Allocate node-local memory only. + * + * %GFP_DMA - Allocation suitable for DMA. + * Should only be used for kmalloc() caches. Otherwise, use a + * slab created with SLAB_DMA. + * * Also it is possible to set different flags by OR'ing * in one or more of the following additional @flags: * * %__GFP_COLD - Request cache-cold pages instead of * trying to return cache-warm pages. * - * %__GFP_DMA - Request memory from the DMA-capable zone. - * * %__GFP_HIGH - This allocation has high priority and may use emergency pools. * - * %__GFP_HIGHMEM - Allocated memory may be from highmem. - * * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail * (think twice before using). * @@ -173,24 +166,29 @@ static inline void *kcalloc(size_t n, size_t size, gfp_t flags) * %__GFP_NOWARN - If allocation fails, don't issue any warnings. * * %__GFP_REPEAT - If allocation fails initially, try once more before failing. + * + * There are other flags available as well, but these are not intended + * for general use, and so are not documented here. For a full list of + * potential flags, always refer to linux/gfp.h. */ -static inline void *kmalloc(size_t size, gfp_t flags) +static inline void *kcalloc(size_t n, size_t size, gfp_t flags) { - return __kmalloc(size, flags); + if (n != 0 && size > ULONG_MAX / n) + return NULL; + return __kmalloc(n * size, flags | __GFP_ZERO); } +#if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB) /** - * kzalloc - allocate memory. The memory is set to zero. + * kmalloc_node - allocate memory from a specific node * @size: how many bytes of memory are required. - * @flags: the type of memory to allocate (see kmalloc). + * @flags: the type of memory to allocate (see kcalloc). + * @node: node to allocate from. + * + * kmalloc() for non-local nodes, used to allocate from a specific node + * if available. Equivalent to kmalloc() in the non-NUMA single-node + * case. */ -static inline void *kzalloc(size_t size, gfp_t flags) -{ - return __kzalloc(size, flags); -} -#endif - -#ifndef CONFIG_NUMA static inline void *kmalloc_node(size_t size, gfp_t flags, int node) { return kmalloc(size, flags); @@ -200,7 +198,15 @@ static inline void *__kmalloc_node(size_t size, gfp_t flags, int node) { return __kmalloc(size, flags); } -#endif /* !CONFIG_NUMA */ + +void *kmem_cache_alloc(struct kmem_cache *, gfp_t); + +static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep, + gfp_t flags, int node) +{ + return kmem_cache_alloc(cachep, flags); +} +#endif /* !CONFIG_NUMA && !CONFIG_SLOB */ /* * kmalloc_track_caller is a special version of kmalloc that records the @@ -245,6 +251,23 @@ extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *); #endif /* DEBUG_SLAB */ +/* + * Shortcuts + */ +static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags) +{ + return kmem_cache_alloc(k, flags | __GFP_ZERO); +} + +/** + * kzalloc - allocate memory. The memory is set to zero. + * @size: how many bytes of memory are required. + * @flags: the type of memory to allocate (see kmalloc). + */ +static inline void *kzalloc(size_t size, gfp_t flags) +{ + return kmalloc(size, flags | __GFP_ZERO); +} + #endif /* __KERNEL__ */ #endif /* _LINUX_SLAB_H */ - |