/*
* Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
*
- * (C) SGI 2006, Christoph Lameter <clameter@sgi.com>
+ * (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
-#ifdef __KERNEL__
-
#include <linux/gfp.h>
#include <linux/types.h>
#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_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
#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
+
+/* 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)
+
/*
* struct kmem_cache related prototypes
*/
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 (*)(void *));
void kmem_cache_destroy(struct kmem_cache *);
int kmem_cache_shrink(struct kmem_cache *);
-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 *);
*/
#define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
sizeof(struct __struct), __alignof__(struct __struct),\
- (__flags), NULL, NULL)
+ (__flags), NULL)
/*
* The largest kmalloc size supported by the slab allocators is
/*
* Common kmalloc functions provided by all allocators
*/
-void *__kzalloc(size_t, gfp_t);
+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
+
/**
* kcalloc - allocate memory for an array. The memory is set to zero.
* @n: number of elements.
*/
static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
{
- if (n != 0 && size > ULONG_MAX / n)
+ if (size != 0 && n > ULONG_MAX / size)
return NULL;
- return __kzalloc(n * size, flags);
+ return __kmalloc(n * size, flags | __GFP_ZERO);
}
-/*
- * 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()
- * kzalloc()
- *
- * 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
-
#if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB)
/**
* kmalloc_node - allocate memory from a specific node
* request comes from.
*/
#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
-extern void *__kmalloc_track_caller(size_t, gfp_t, void*);
+extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
#define kmalloc_track_caller(size, flags) \
- __kmalloc_track_caller(size, flags, __builtin_return_address(0))
+ __kmalloc_track_caller(size, flags, _RET_IP_)
#else
#define kmalloc_track_caller(size, flags) \
__kmalloc(size, flags)
* allocation request comes from.
*/
#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
-extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
+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, \
- __builtin_return_address(0))
+ _RET_IP_)
#else
#define kmalloc_node_track_caller(size, flags, node) \
__kmalloc_node(size, flags, node)
#define kmalloc_node_track_caller(size, flags, node) \
kmalloc_track_caller(size, flags)
-#endif /* DEBUG_SLAB */
+#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);
+}
+
+void __init kmem_cache_init_late(void);
-#endif /* __KERNEL__ */
#endif /* _LINUX_SLAB_H */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff