/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1999-2001, 2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef _SYS_VMEM_IMPL_H
#define _SYS_VMEM_IMPL_H

#include <sys/vmem.h>
#include <sys/kstat.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/thread.h>
#include <sys/systm.h>

#ifdef  __cplusplus
extern "C" {
#endif

typedef struct vmem_seg vmem_seg_t;

#define VMEM_STACK_DEPTH        20

struct vmem_seg {
        /*
         * The first four fields must match vmem_freelist_t exactly.
         */
        uintptr_t       vs_start;       /* start of segment (inclusive) */
        uintptr_t       vs_end;         /* end of segment (exclusive) */
        vmem_seg_t      *vs_knext;      /* next of kin (alloc, free, span) */
        vmem_seg_t      *vs_kprev;      /* prev of kin */

        vmem_seg_t      *vs_anext;      /* next in arena */
        vmem_seg_t      *vs_aprev;      /* prev in arena */
        uint8_t         vs_type;        /* alloc, free, span */
        uint8_t         vs_import;      /* non-zero if segment was imported */
        uint8_t         vs_depth;       /* stack depth if KMF_AUDIT active */
        /*
         * The following fields are present only when KMF_AUDIT is set.
         */
        kthread_t       *vs_thread;
        hrtime_t        vs_timestamp;
        pc_t            vs_stack[VMEM_STACK_DEPTH];
};

typedef struct vmem_freelist {
        uintptr_t       vs_start;       /* always zero */
        uintptr_t       vs_end;         /* segment size */
        vmem_seg_t      *vs_knext;      /* next of kin */
        vmem_seg_t      *vs_kprev;      /* prev of kin */
} vmem_freelist_t;

#define VS_SIZE(vsp)    ((vsp)->vs_end - (vsp)->vs_start)

/*
 * Segment hashing
 */
#define VMEM_HASH_INDEX(a, s, q, m)                                     \
        ((((a) + ((a) >> (s)) + ((a) >> ((s) << 1))) >> (q)) & (m))

#define VMEM_HASH(vmp, addr)                                            \
        (&(vmp)->vm_hash_table[VMEM_HASH_INDEX(addr,                    \
        (vmp)->vm_hash_shift, (vmp)->vm_qshift, (vmp)->vm_hash_mask)])

#define VMEM_QCACHE_SLABSIZE(max) \
        MAX(1 << highbit(3 * (max)), 64)

#define VMEM_NAMELEN            30
#define VMEM_HASH_INITIAL       16
#define VMEM_NQCACHE_MAX        16
#define VMEM_FREELISTS          (sizeof (void *) * 8)

typedef struct vmem_kstat {
        kstat_named_t   vk_mem_inuse;   /* memory in use */
        kstat_named_t   vk_mem_import;  /* memory imported */
        kstat_named_t   vk_mem_total;   /* total memory in arena */
        kstat_named_t   vk_source_id;   /* vmem id of vmem source */
        kstat_named_t   vk_alloc;       /* number of allocations */
        kstat_named_t   vk_free;        /* number of frees */
        kstat_named_t   vk_wait;        /* number of allocations that waited */
        kstat_named_t   vk_fail;        /* number of allocations that failed */
        kstat_named_t   vk_lookup;      /* hash lookup count */
        kstat_named_t   vk_search;      /* freelist search count */
        kstat_named_t   vk_populate_wait;       /* populates that waited */
        kstat_named_t   vk_populate_fail;       /* populates that failed */
        kstat_named_t   vk_contains;            /* vmem_contains() calls */
        kstat_named_t   vk_contains_search;     /* vmem_contains() search cnt */
} vmem_kstat_t;

struct vmem {
        char            vm_name[VMEM_NAMELEN];  /* arena name */
        kcondvar_t      vm_cv;          /* cv for blocking allocations */
        kmutex_t        vm_lock;        /* arena lock */
        uint32_t        vm_id;          /* vmem id */
        uint32_t        vm_mtbf;        /* induced alloc failure rate */
        int             vm_cflags;      /* arena creation flags */
        int             vm_qshift;      /* log2(vm_quantum) */
        size_t          vm_quantum;     /* vmem quantum */
        size_t          vm_qcache_max;  /* maximum size to front by kmem */
        size_t          vm_min_import;  /* smallest amount to import */
        void            *(*vm_source_alloc)(vmem_t *, size_t, int);
        void            (*vm_source_free)(vmem_t *, void *, size_t);
        vmem_t          *vm_source;     /* vmem source for imported memory */
        vmem_t          *vm_next;       /* next in vmem_list */
        kstat_t         *vm_ksp;        /* kstat */
        ssize_t         vm_nsegfree;    /* number of free vmem_seg_t's */
        vmem_seg_t      *vm_segfree;    /* free vmem_seg_t list */
        vmem_seg_t      **vm_hash_table; /* allocated-segment hash table */
        size_t          vm_hash_mask;   /* hash_size - 1 */
        size_t          vm_hash_shift;  /* log2(vm_hash_mask + 1) */
        ulong_t         vm_freemap;     /* bitmap of non-empty freelists */
        vmem_seg_t      vm_seg0;        /* anchor segment */
        vmem_seg_t      vm_rotor;       /* rotor for VM_NEXTFIT allocations */
        vmem_seg_t      *vm_hash0[VMEM_HASH_INITIAL];   /* initial hash table */
        void            *vm_qcache[VMEM_NQCACHE_MAX];   /* quantum caches */
        vmem_freelist_t vm_freelist[VMEM_FREELISTS + 1]; /* power-of-2 flists */
        vmem_kstat_t    vm_kstat;       /* kstat data */
};

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_VMEM_IMPL_H */