| /* |
| * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk). |
| * |
| * (C) SGI 2006, Christoph Lameter |
| * Cleaned up and restructured to ease the addition of alternative |
| * implementations of SLAB allocators. |
| */ |
| |
| #ifndef _LINUX_SLAB_H |
| #define _LINUX_SLAB_H |
| |
| #include <linux/gfp.h> |
| #include <linux/types.h> |
| |
| /* |
| * Flags to pass to kmem_cache_create(). |
| * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set. |
| */ |
| #define SLAB_DEBUG_FREE 0x00000100UL /* DEBUG: Perform (expensive) checks on free */ |
| #define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */ |
| #define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */ |
| #define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */ |
| #define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */ |
| #define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */ |
| #define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */ |
| /* |
| * SLAB_DESTROY_BY_RCU - **WARNING** READ THIS! |
| * |
| * This delays freeing the SLAB page by a grace period, it does _NOT_ |
| * delay object freeing. This means that if you do kmem_cache_free() |
| * that memory location is free to be reused at any time. Thus it may |
| * be possible to see another object there in the same RCU grace period. |
| * |
| * This feature only ensures the memory location backing the object |
| * stays valid, the trick to using this is relying on an independent |
| * object validation pass. Something like: |
| * |
| * rcu_read_lock() |
| * again: |
| * obj = lockless_lookup(key); |
| * if (obj) { |
| * if (!try_get_ref(obj)) // might fail for free objects |
| * goto again; |
| * |
| * if (obj->key != key) { // not the object we expected |
| * put_ref(obj); |
| * goto again; |
| * } |
| * } |
| * rcu_read_unlock(); |
| * |
| * See also the comment on struct slab_rcu in mm/slab.c. |
| */ |
| #define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */ |
| #define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */ |
| #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */ |
| |
| /* Flag to prevent checks on free */ |
| #ifdef CONFIG_DEBUG_OBJECTS |
| # define SLAB_DEBUG_OBJECTS 0x00400000UL |
| #else |
| # define SLAB_DEBUG_OBJECTS 0x00000000UL |
| #endif |
| |
| #define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */ |
| |
| /* Don't track use of uninitialized memory */ |
| #ifdef CONFIG_KMEMCHECK |
| # define SLAB_NOTRACK 0x01000000UL |
| #else |
| # define SLAB_NOTRACK 0x00000000UL |
| #endif |
| #ifdef CONFIG_FAILSLAB |
| # define SLAB_FAILSLAB 0x02000000UL /* Fault injection mark */ |
| #else |
| # define SLAB_FAILSLAB 0x00000000UL |
| #endif |
| |
| /* The following flags affect the page allocator grouping pages by mobility */ |
| #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ |
| #define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ |
| /* |
| * 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) |
| |
| /* |
| * Common fields provided in kmem_cache by all slab allocators |
| * This struct is either used directly by the allocator (SLOB) |
| * or the allocator must include definitions for all fields |
| * provided in kmem_cache_common in their definition of kmem_cache. |
| * |
| * Once we can do anonymous structs (C11 standard) we could put a |
| * anonymous struct definition in these allocators so that the |
| * separate allocations in the kmem_cache structure of SLAB and |
| * SLUB is no longer needed. |
| */ |
| #ifdef CONFIG_SLOB |
| struct kmem_cache { |
| unsigned int object_size;/* The original size of the object */ |
| unsigned int size; /* The aligned/padded/added on size */ |
| unsigned int align; /* Alignment as calculated */ |
| unsigned long flags; /* Active flags on the slab */ |
| const char *name; /* Slab name for sysfs */ |
| int refcount; /* Use counter */ |
| void (*ctor)(void *); /* Called on object slot creation */ |
| struct list_head list; /* List of all slab caches on the system */ |
| }; |
| #endif |
| |
| /* |
| * struct kmem_cache related prototypes |
| */ |
| void __init kmem_cache_init(void); |
| int slab_is_available(void); |
| |
| struct kmem_cache *kmem_cache_create(const char *, size_t, size_t, |
| unsigned long, |
| void (*)(void *)); |
| void kmem_cache_destroy(struct kmem_cache *); |
| int kmem_cache_shrink(struct kmem_cache *); |
| void kmem_cache_free(struct kmem_cache *, void *); |
| |
| /* |
| * Please use this macro to create slab caches. Simply specify the |
| * name of the structure and maybe some flags that are listed above. |
| * |
| * The alignment of the struct determines object alignment. If you |
| * f.e. add ____cacheline_aligned_in_smp to the struct declaration |
| * then the objects will be properly aligned in SMP configurations. |
| */ |
| #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\ |
| sizeof(struct __struct), __alignof__(struct __struct),\ |
| (__flags), NULL) |
| |
| /* |
| * The largest kmalloc size supported by the slab allocators is |
| * 32 megabyte (2^25) or the maximum allocatable page order if that is |
| * less than 32 MB. |
| * |
| * WARNING: Its not easy to increase this value since the allocators have |
| * to do various tricks to work around compiler limitations in order to |
| * ensure proper constant folding. |
| */ |
| #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ |
| (MAX_ORDER + PAGE_SHIFT - 1) : 25) |
| |
| #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH) |
| #define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT) |
| |
| /* |
| * Some archs want to perform DMA into kmalloc caches and need a guaranteed |
| * alignment larger than the alignment of a 64-bit integer. |
| * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that. |
| */ |
| #ifdef ARCH_DMA_MINALIGN |
| #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN |
| #else |
| #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) |
| #endif |
| |
| /* |
| * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment. |
| * Intended for arches that get misalignment faults even for 64 bit integer |
| * aligned buffers. |
| */ |
| #ifndef ARCH_SLAB_MINALIGN |
| #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long) |
| #endif |
| |
| /* |
| * Common kmalloc functions provided by all allocators |
| */ |
| void * __must_check __krealloc(const void *, size_t, gfp_t); |
| void * __must_check krealloc(const void *, size_t, gfp_t); |
| void kfree(const void *); |
| void kzfree(const void *); |
| size_t ksize(const void *); |
| |
| /* |
| * 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. |
| * |
| * 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. |
| */ |
| #ifdef CONFIG_SLUB |
| #include <linux/slub_def.h> |
| #elif defined(CONFIG_SLOB) |
| #include <linux/slob_def.h> |
| #else |
| #include <linux/slab_def.h> |
| #endif |
| |
| /** |
| * kmalloc_array - allocate memory for an array. |
| * @n: number of elements. |
| * @size: element size. |
| * @flags: the type of memory to allocate. |
| * |
| * 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. May use emergency pools. |
| * For example, use this inside interrupt handlers. |
| * |
| * %GFP_HIGHUSER - Allocate pages from high memory. |
| * |
| * %GFP_NOIO - Do not do any I/O at all while trying to get memory. |
| * |
| * %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_HIGH - This allocation has high priority and may use emergency pools. |
| * |
| * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail |
| * (think twice before using). |
| * |
| * %__GFP_NORETRY - If memory is not immediately available, |
| * then give up at once. |
| * |
| * %__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_array(size_t n, size_t size, gfp_t flags) |
| { |
| if (size != 0 && n > SIZE_MAX / size) |
| return NULL; |
| return __kmalloc(n * size, flags); |
| } |
| |
| /** |
| * 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 (see kmalloc). |
| */ |
| static inline void *kcalloc(size_t n, size_t size, gfp_t flags) |
| { |
| return kmalloc_array(n, size, flags | __GFP_ZERO); |
| } |
| |
| #if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB) |
| /** |
| * kmalloc_node - allocate memory from a specific node |
| * @size: how many bytes of memory are required. |
| * @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 *kmalloc_node(size_t size, gfp_t flags, int node) |
| { |
| return kmalloc(size, flags); |
| } |
| |
| static inline void *__kmalloc_node(size_t size, gfp_t flags, int node) |
| { |
| return __kmalloc(size, flags); |
| } |
| |
| 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 |
| * calling function of the routine calling it for slab leak tracking instead |
| * of just the calling function (confusing, eh?). |
| * It's useful when the call to kmalloc comes from a widely-used standard |
| * allocator where we care about the real place the memory allocation |
| * request comes from. |
| */ |
| #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \ |
| (defined(CONFIG_SLAB) && defined(CONFIG_TRACING)) || \ |
| (defined(CONFIG_SLOB) && defined(CONFIG_TRACING)) |
| extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long); |
| #define kmalloc_track_caller(size, flags) \ |
| __kmalloc_track_caller(size, flags, _RET_IP_) |
| #else |
| #define kmalloc_track_caller(size, flags) \ |
| __kmalloc(size, flags) |
| #endif /* DEBUG_SLAB */ |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * kmalloc_node_track_caller is a special version of kmalloc_node that |
| * records the calling function of the routine calling it for slab leak |
| * tracking instead of just the calling function (confusing, eh?). |
| * It's useful when the call to kmalloc_node comes from a widely-used |
| * standard allocator where we care about the real place the memory |
| * allocation request comes from. |
| */ |
| #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \ |
| (defined(CONFIG_SLAB) && defined(CONFIG_TRACING)) || \ |
| (defined(CONFIG_SLOB) && defined(CONFIG_TRACING)) |
| extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long); |
| #define kmalloc_node_track_caller(size, flags, node) \ |
| __kmalloc_node_track_caller(size, flags, node, \ |
| _RET_IP_) |
| #else |
| #define kmalloc_node_track_caller(size, flags, node) \ |
| __kmalloc_node(size, flags, node) |
| #endif |
| |
| #else /* CONFIG_NUMA */ |
| |
| #define kmalloc_node_track_caller(size, flags, node) \ |
| kmalloc_track_caller(size, flags) |
| |
| #endif /* CONFIG_NUMA */ |
| |
| /* |
| * 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); |
| } |
| |
| /** |
| * kzalloc_node - allocate zeroed memory from a particular memory node. |
| * @size: how many bytes of memory are required. |
| * @flags: the type of memory to allocate (see kmalloc). |
| * @node: memory node from which to allocate |
| */ |
| static inline void *kzalloc_node(size_t size, gfp_t flags, int node) |
| { |
| return kmalloc_node(size, flags | __GFP_ZERO, node); |
| } |
| |
| /* |
| * Determine the size of a slab object |
| */ |
| static inline unsigned int kmem_cache_size(struct kmem_cache *s) |
| { |
| return s->object_size; |
| } |
| |
| void __init kmem_cache_init_late(void); |
| |
| #endif /* _LINUX_SLAB_H */ |