Slab allocators: consolidate code for krealloc in mm/util.c
The size of a kmalloc object is readily available via ksize(). ksize is
provided by all allocators and thus we can implement krealloc in a generic
way.
Implement krealloc in mm/util.c and drop slab specific implementations of
krealloc.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/util.c b/mm/util.c
index ace2aea..18396ea 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -58,6 +58,40 @@
}
EXPORT_SYMBOL(kmemdup);
+/**
+ * krealloc - reallocate memory. The contents will remain unchanged.
+ * @p: object to reallocate memory for.
+ * @new_size: how many bytes of memory are required.
+ * @flags: the type of memory to allocate.
+ *
+ * The contents of the object pointed to are preserved up to the
+ * lesser of the new and old sizes. If @p is %NULL, krealloc()
+ * behaves exactly like kmalloc(). If @size is 0 and @p is not a
+ * %NULL pointer, the object pointed to is freed.
+ */
+void *krealloc(const void *p, size_t new_size, gfp_t flags)
+{
+ void *ret;
+ size_t ks;
+
+ if (unlikely(!new_size)) {
+ kfree(p);
+ return NULL;
+ }
+
+ ks = ksize(p);
+ if (ks >= new_size)
+ return (void *)p;
+
+ ret = kmalloc_track_caller(new_size, flags);
+ if (ret) {
+ memcpy(ret, p, min(new_size, ks));
+ kfree(p);
+ }
+ return ret;
+}
+EXPORT_SYMBOL(krealloc);
+
/*
* strndup_user - duplicate an existing string from user space
*