/*      $NetBSD: vmem_impl.h,v 1.8 2023/12/03 19:34:08 thorpej Exp $    */

/*-
 * Copyright (c)2006 YAMAMOTO Takashi,
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */

/*
 * Data structures private to vmem.
 */

#ifndef _SYS_VMEM_IMPL_H_
#define _SYS_VMEM_IMPL_H_

#include <sys/types.h>

#if defined(_KERNEL)
#define QCACHE
#include <sys/pool.h>
#include <sys/vmem.h>

#define LOCK_DECL(name)         \
    kmutex_t name; char lockpad[COHERENCY_UNIT - sizeof(kmutex_t)]

#define CONDVAR_DECL(name)      \
    kcondvar_t name

#else /* defined(_KERNEL) */
#include <stdio.h>
#include <errno.h>
#include <assert.h>
#include <stdlib.h>
#include <string.h>

#include "vmem.h"

#define LOCK_DECL(name)         /* nothing */
#define CONDVAR_DECL(name)      /* nothing */
#endif /* defined(_KERNEL) */

#define VMEM_MAXORDER           (sizeof(vmem_size_t) * CHAR_BIT)

typedef struct vmem_btag bt_t;

TAILQ_HEAD(vmem_seglist, vmem_btag);
LIST_HEAD(vmem_freelist, vmem_btag);
LIST_HEAD(vmem_hashlist, vmem_btag);

#if defined(QCACHE)
#define VMEM_QCACHE_IDX_MAX     16

#define QC_NAME_MAX     16

struct qcache {
        pool_cache_t qc_cache;
        vmem_t *qc_vmem;
        char qc_name[QC_NAME_MAX];
};
typedef struct qcache qcache_t;
#define QC_POOL_TO_QCACHE(pool) ((qcache_t *)(pool->pr_qcache))
#endif /* defined(QCACHE) */

#define VMEM_NAME_MAX   16

/* vmem arena */
struct vmem {
        CONDVAR_DECL(vm_cv);
        LOCK_DECL(vm_lock);
        vm_flag_t vm_flags;
        vmem_import_t *vm_importfn;
        vmem_release_t *vm_releasefn;
        size_t vm_nfreetags;
        LIST_HEAD(, vmem_btag) vm_freetags;
        void *vm_arg;
        struct vmem_seglist vm_seglist;
        struct vmem_freelist vm_freelist[VMEM_MAXORDER];
        size_t vm_hashsize;
        size_t vm_hashmask;
        size_t vm_nbusytag;
        size_t vm_maxbusytag;
        struct vmem_hashlist *vm_hashlist;
        struct vmem_hashlist vm_hash0;
        size_t vm_quantum_mask;
        int vm_quantum_shift;
        size_t vm_size;
        size_t vm_inuse;
        char vm_name[VMEM_NAME_MAX+1];
        LIST_ENTRY(vmem) vm_alllist;

#if defined(QCACHE)
        /* quantum cache */
        size_t vm_qcache_max;
        struct pool_allocator vm_qcache_allocator;
        qcache_t vm_qcache_store[VMEM_QCACHE_IDX_MAX];
        qcache_t *vm_qcache[VMEM_QCACHE_IDX_MAX];
#endif /* defined(QCACHE) */
};

/* boundary tag */
struct vmem_btag {
        TAILQ_ENTRY(vmem_btag) bt_seglist;
        union {
                LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */
                LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */
        } bt_u;
#define bt_hashlist     bt_u.u_hashlist
#define bt_freelist     bt_u.u_freelist
        vmem_addr_t bt_start;
        vmem_size_t bt_size;
        short bt_type;
        short bt_flags;
};

#define BT_TYPE_SPAN            1
#define BT_TYPE_SPAN_STATIC     2
#define BT_TYPE_FREE            3
#define BT_TYPE_BUSY            4
#define BT_ISSPAN_P(bt) ((bt)->bt_type <= BT_TYPE_SPAN_STATIC)

#define BT_F_PRIVATE            0x0001

#define BT_END(bt)      ((bt)->bt_start + (bt)->bt_size - 1)

/*
 * Provide an estimated number of boundary tags needed for a given
 * number of allocations from the vmem arena.  This estimate is
 * based on 2 boundary tags per allocation (see vmem_xalloc()) and
 * 2 boundary tags per added span (one to describe the span, one to
 * describe the span's free space; see vmem_add1()).
 */
#define VMEM_EST_BTCOUNT(ns, na)        (((ns) * 2) + ((na) * 2))

vmem_t *        vmem_init(vmem_t *, const char *, vmem_addr_t, vmem_size_t,
                    vmem_size_t, vmem_import_t *, vmem_release_t *, vmem_t *,
                    vmem_size_t, vm_flag_t, int);
void            vmem_add_bts(vmem_t *, struct vmem_btag *, unsigned int);

#endif /* !_SYS_VMEM_IMPL_H_ */