/*
 * Copyright (c) 2026, Chloe M.
 * Provided under the BSD-3 clause.
 *
 * Description: Pool allocator
 * Author:      Chloe M.
 */

#ifndef _EX_POOL_H_
#define _EX_POOL_H_ 1

#include <ptdef.h>

/* Maximum levels per region */
#define POOL_LEVEL_MAX 8

/* Minimum log2 granularity */
#define POOL_MIN_LOG2  3

/* Compute the granularity at a specific level */
#define POOL_LEVEL_GRAN(X) \
    (1 << ((X) + POOL_MIN_LOG2))

/*
 * A pool page represents a single allocatable
 * unit within a pool segment.
 *
 * @Bitmap: Bitmap within pool page
 * @Next:   Next page within list
 */
typedef struct _POOL_PAGE {
    UQUAD Bitmap;
    struct _POOL_PAGE *Next;
} POOL_PAGE;

/*
 * A pool segment represents a list of pages at a specific
 * granularity.
 *
 * @LastPage:  Last page in segment
 * @PageCount: Number of pages in this segment
 */
typedef struct {
    POOL_PAGE *LastPage;
    USIZE PageCount;
} POOL_SEGMENT;

/*
 * A pool region represents a whole area in which several
 * pool levels can reside.
 *
 * @Level: Segment levels
 */
typedef struct {
    POOL_SEGMENT Level[POOL_LEVEL_MAX];
} POOL_REGION;

#endif  /* !_EX_POOL_H_ */