[PATCH] introduce and use kzalloc

[linux-2.6] / mm / slab.c

diff --git a/mm/slab.c b/mm/slab.c
index 75127a6f1fd9d604cc8c0bc2ddf2db3bac887735..d7c4443991fe8e29e16dfaffa30a1711c6844c30 100644 (file)
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2558,24 +2558,18 @@ void kmem_cache_free(kmem_cache_t *cachep, void *objp)
 EXPORT_SYMBOL(kmem_cache_free);
 
 /**
- * kcalloc - allocate memory for an array. The memory is set to zero.
- * @n: number of elements.
- * @size: element size.
+ * kzalloc - allocate memory. The memory is set to zero.
+ * @size: how many bytes of memory are required.
  * @flags: the type of memory to allocate.
  */
-void *kcalloc(size_t n, size_t size, unsigned int __nocast flags)
+void *kzalloc(size_t size, unsigned int __nocast flags)
 {
-       void *ret = NULL;
-
-       if (n != 0 && size > INT_MAX / n)
-               return ret;
-
-       ret = kmalloc(n * size, flags);
+       void *ret = kmalloc(size, flags);
        if (ret)
-               memset(ret, 0, n * size);
+               memset(ret, 0, size);
        return ret;
 }
-EXPORT_SYMBOL(kcalloc);
+EXPORT_SYMBOL(kzalloc);
 
 /**
  * kfree - free previously allocated memory
@@ -3076,20 +3070,24 @@ ssize_t slabinfo_write(struct file *file, const char __user *buffer,
 }
 #endif
 
+/**
+ * ksize - get the actual amount of memory allocated for a given object
+ * @objp: Pointer to the object
+ *
+ * kmalloc may internally round up allocations and return more memory
+ * than requested. ksize() can be used to determine the actual amount of
+ * memory allocated. The caller may use this additional memory, even though
+ * a smaller amount of memory was initially specified with the kmalloc call.
+ * The caller must guarantee that objp points to a valid object previously
+ * allocated with either kmalloc() or kmem_cache_alloc(). The object
+ * must not be freed during the duration of the call.
+ */
 unsigned int ksize(const void *objp)
 {
-       kmem_cache_t *c;
-       unsigned long flags;
-       unsigned int size = 0;
-
-       if (likely(objp != NULL)) {
-               local_irq_save(flags);
-               c = GET_PAGE_CACHE(virt_to_page(objp));
-               size = kmem_cache_size(c);
-               local_irq_restore(flags);
-       }
+       if (unlikely(objp == NULL))
+               return 0;
 
-       return size;
+       return obj_reallen(GET_PAGE_CACHE(virt_to_page(objp)));
 }