/* Copyright (c) 2007, Sandia National Laboratories */

#ifndef _LWK_BUDDY_H
#define _LWK_BUDDY_H

#include <lwk/list.h>

/**
 * This structure stores the state of a buddy system memory allocator object.
 */
struct buddy_mempool {
	unsigned long    base_addr;    /* base address of the memory pool */
	unsigned long    pool_order;   /* size of memory pool = 2^pool_order */
	unsigned long    min_order;    /* minimum allocatable block size */

	unsigned long    num_blocks;   /* number of bits in tag_bits */
	unsigned long    *tag_bits;    /* one bit for each 2^min_order block
	                                *   0 = block is allocated
	                                *   1 = block is available
	                                */

	struct list_head *avail;       /* one free list for each block size,
	                                * indexed by block order:
	                                *   avail[i] = free list of 2^i blocks
	                                */
};

struct buddy_mempool *
buddy_init(
	unsigned long base_addr,
	unsigned long pool_order,
	unsigned long min_order
);

void *buddy_alloc(struct buddy_mempool *mp, unsigned long order);
void buddy_free(struct buddy_mempool *mp, void *addr, unsigned long order);

void buddy_dump_mempool(struct buddy_mempool *mp);

#endif