/*
* Copyright (C) 2005 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.
*/
#ifndef __BUDDY_H__
#define __BUDDY_H__
#include <arch/types.h>
#include <typedefs.h>
#define BUDDY_SYSTEM_INNER_BLOCK 0xff
/** Buddy system operations to be implemented by each implementations. */
struct buddy_system_operations {
link_t *(* find_buddy)(buddy_system_t *, link_t *); /**< Return pointer to left-side or right-side buddy for block passed as argument. */
link_t *(* bisect)(buddy_system_t *, link_t *); /**< Bisect the block passed as argument and return pointer to the new right-side buddy. */
link_t *(* coalesce)(buddy_system_t *, link_t *, link_t *); /**< Coalesce two buddies into a bigger block. */
void (*set_order)(buddy_system_t *, link_t *, __u8); /**< Set order of block passed as argument. */
__u8 (*get_order)(buddy_system_t *, link_t *); /**< Return order of block passed as argument. */
void (*mark_busy)(buddy_system_t *, link_t *); /**< Mark block as busy */
};
struct buddy_system {
__u8 max_order;
link_t *order;
buddy_system_operations_t *op;
void *data; /**< Pointer to be used by the implementation. */
};
extern buddy_system_t *buddy_system_create(__u8 max_order, buddy_system_operations_t *op, void *data);
extern link_t *buddy_system_alloc(buddy_system_t *b, __u8 i);
extern bool buddy_system_can_alloc(buddy_system_t *b, __u8 order);
extern void buddy_system_free(buddy_system_t *b, link_t *block);
#endif