Index: kernel/generic/include/lib/ra.h
===================================================================
--- kernel/generic/include/lib/ra.h	(revision 9fe7d6c017059754255cdf56efc55c87ed2e5241)
+++ kernel/generic/include/lib/ra.h	(revision 9fe7d6c017059754255cdf56efc55c87ed2e5241)
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2011 Jakub Jermar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup generic
+ * @{
+ */
+/** @file
+ */
+
+#ifndef KERN_RA_H_
+#define KERN_RA_H_
+
+#include <typedefs.h>
+#include <adt/list.h>
+#include <adt/hash_table.h>
+
+typedef struct {
+	list_t spans;		/**< List of arena's spans. */
+} ra_arena_t;
+
+typedef struct {
+	link_t span_link;	/**< Link for the arena's list of spans. */
+
+	list_t segments;	/**< List of span's segments. */
+
+	size_t max_order;	/**< Base 2 logarithm of span's size. */
+	list_t *free;		/**< max_order segment free lists. */
+
+	hash_table_t used;
+} ra_span_t;
+
+typedef struct {
+	link_t segment_link;	/**< Link for the span's list of segments. */
+	link_t free_link;	/**< Link for the span's free list. */
+	link_t used_link;	/**< Link for the span's used hash table. */
+
+	uintptr_t base;		/**< Segment base. */
+	uintptr_t size;		/**< Segment size. */
+	
+} ra_segment_t;
+
+extern ra_arena_t *ra_arena_create(uintptr_t, size_t);
+extern void ra_span_add(ra_arena_t *, uintptr_t, size_t);
+extern uintptr_t ra_alloc(ra_arena_t *, size_t, size_t);
+extern void ra_free(ra_arena_t *, uintptr_t, size_t);
+
+#endif
+
+/** @}
+ */