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/*        $NetBSD: extent.h,v 1.19 2012/01/27 18:53:10 para Exp $        */
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/*-
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 * Copyright (c) 1996, 1998 The NetBSD Foundation, Inc.
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 * All rights reserved.
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 *
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 * This code is derived from software contributed to The NetBSD Foundation
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 * by Jason R. Thorpe.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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 * POSSIBILITY OF SUCH DAMAGE.
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 */
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#ifndef _SYS_EXTENT_H_
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#define _SYS_EXTENT_H_
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#include <sys/queue.h>
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#include <sys/mutex.h>
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#include <sys/condvar.h>
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struct extent_region {
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        LIST_ENTRY(extent_region) er_link;        /* link in region list */
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        u_long         er_start;                /* start of region */
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        u_long        er_end;                        /* end of region */
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        int        er_flags;                /* misc. flags */
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};
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/* er_flags */
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#define ER_ALLOC        0x01        /* region descriptor dynamically allocated */
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struct extent {
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        const char *ex_name;                /* name of extent */
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        kmutex_t ex_lock;                /* lock on this extent */
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        kcondvar_t ex_cv;                /* synchronization */
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                                        /* allocated regions in extent */
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        LIST_HEAD(, extent_region) ex_regions;
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        u_long        ex_start;                /* start of extent */
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        u_long        ex_end;                        /* end of extent */
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        int        ex_flags;                /* misc. information */
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};
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struct extent_fixed {
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        struct extent        fex_extent;        /* MUST BE FIRST */
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                                        /* freelist of region descriptors */
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        LIST_HEAD(, extent_region) fex_freelist;
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        void *                fex_storage;        /* storage space for descriptors */
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        size_t                fex_storagesize; /* size of storage space */
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};
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/* ex_flags; for internal use only */
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#define EXF_FIXED        0x01                /* extent uses fixed storage */
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#define EXF_NOCOALESCE        0x02                /* coalescing of regions not allowed */
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#define EXF_FLWANTED        0x08                /* someone asleep on freelist */
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#define EXF_BITS        "\20\4FLWANTED\2NOCOALESCE\1FIXED"
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/* misc. flags passed to extent functions */
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#define EX_NOWAIT        0x00                /* not safe to sleep */
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#define EX_WAITOK        0x01                /* safe to sleep */
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#define EX_FAST                0x02                /* take first fit in extent_alloc() */
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#define EX_CATCH        0x04                /* catch signals while sleeping */
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#define EX_NOCOALESCE        0x08                /* create a non-coalescing extent */
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#define EX_MALLOCOK        0x10                /* safe to call kmem_alloc() */
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#define EX_WAITSPACE        0x20                /* wait for space to become free */
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#define EX_BOUNDZERO        0x40                /* boundary lines start at 0 */
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/*
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 * Special place holders for "alignment" and "boundary" arguments,
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 * in the event the caller doesn't wish to use those features.
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 */
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#define EX_NOALIGN        1                /* don't do alignment */
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#define EX_NOBOUNDARY        0                /* don't do boundary checking */
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#if defined(_KERNEL) || defined(_EXTENT_TESTING)
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#define EXTENT_FIXED_STORAGE_SIZE(_nregions)                \
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        (ALIGN(sizeof(struct extent_fixed)) +                \
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        ((ALIGN(sizeof(struct extent_region))) *        \
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         (_nregions)))
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struct        extent *extent_create(const char *, u_long, u_long,
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            void *, size_t, int);
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void        extent_destroy(struct extent *);
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int        extent_alloc_subregion1(struct extent *, u_long, u_long,
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            u_long, u_long, u_long, u_long, int, u_long *);
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int        extent_alloc_subregion(struct extent *, u_long, u_long,
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            u_long, u_long, u_long, int, u_long *);
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int        extent_alloc_region(struct extent *, u_long, u_long, int);
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int        extent_alloc1(struct extent *, u_long, u_long, u_long, u_long, int,
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            u_long *);
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int        extent_alloc(struct extent *, u_long, u_long, u_long, int, u_long *);
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int        extent_free(struct extent *, u_long, u_long, int);
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void        extent_print(struct extent *);
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void        extent_init(void);
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#endif /* _KERNEL || _EXTENT_TESTING */
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#endif /* ! _SYS_EXTENT_H_ */