121 lines
2.9 KiB
C
121 lines
2.9 KiB
C
/*
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* Slab allocator functions that are independent of the allocator strategy
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*
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* (C) 2012 Christoph Lameter <cl@linux.com>
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*/
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <linux/poison.h>
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#include <linux/interrupt.h>
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#include <linux/memory.h>
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#include <linux/compiler.h>
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#include <linux/module.h>
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#include <linux/cpu.h>
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#include <linux/uaccess.h>
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#include <asm/cacheflush.h>
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#include <asm/tlbflush.h>
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#include <asm/page.h>
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#include "slab.h"
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enum slab_state slab_state;
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LIST_HEAD(slab_caches);
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DEFINE_MUTEX(slab_mutex);
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/*
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* kmem_cache_create - Create a cache.
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* @name: A string which is used in /proc/slabinfo to identify this cache.
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* @size: The size of objects to be created in this cache.
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* @align: The required alignment for the objects.
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* @flags: SLAB flags
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* @ctor: A constructor for the objects.
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*
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* Returns a ptr to the cache on success, NULL on failure.
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* Cannot be called within a interrupt, but can be interrupted.
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* The @ctor is run when new pages are allocated by the cache.
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*
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* The flags are
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*
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* %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
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* to catch references to uninitialised memory.
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*
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* %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
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* for buffer overruns.
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*
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* %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
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* cacheline. This can be beneficial if you're counting cycles as closely
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* as davem.
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*/
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struct kmem_cache *kmem_cache_create(const char *name, size_t size, size_t align,
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unsigned long flags, void (*ctor)(void *))
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{
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struct kmem_cache *s = NULL;
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#ifdef CONFIG_DEBUG_VM
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if (!name || in_interrupt() || size < sizeof(void *) ||
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size > KMALLOC_MAX_SIZE) {
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printk(KERN_ERR "kmem_cache_create(%s) integrity check"
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" failed\n", name);
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goto out;
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}
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#endif
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get_online_cpus();
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mutex_lock(&slab_mutex);
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#ifdef CONFIG_DEBUG_VM
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list_for_each_entry(s, &slab_caches, list) {
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char tmp;
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int res;
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/*
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* This happens when the module gets unloaded and doesn't
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* destroy its slab cache and no-one else reuses the vmalloc
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* area of the module. Print a warning.
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*/
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res = probe_kernel_address(s->name, tmp);
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if (res) {
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printk(KERN_ERR
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"Slab cache with size %d has lost its name\n",
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s->object_size);
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continue;
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}
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if (!strcmp(s->name, name)) {
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printk(KERN_ERR "kmem_cache_create(%s): Cache name"
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" already exists.\n",
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name);
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dump_stack();
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s = NULL;
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goto oops;
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}
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}
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WARN_ON(strchr(name, ' ')); /* It confuses parsers */
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#endif
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s = __kmem_cache_create(name, size, align, flags, ctor);
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#ifdef CONFIG_DEBUG_VM
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oops:
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#endif
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mutex_unlock(&slab_mutex);
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put_online_cpus();
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#ifdef CONFIG_DEBUG_VM
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out:
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#endif
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if (!s && (flags & SLAB_PANIC))
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panic("kmem_cache_create: Failed to create slab '%s'\n", name);
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return s;
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}
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EXPORT_SYMBOL(kmem_cache_create);
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int slab_is_available(void)
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{
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return slab_state >= UP;
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}
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