Project

General

Profile

Statistics
| Revision:

root / lab4 / .minix-src / include / sys / extent.h @ 13

History | View | Annotate | Download (4.46 KB)

1 13 up20180614
/*        $NetBSD: extent.h,v 1.19 2012/01/27 18:53:10 para Exp $        */
2
3
/*-
4
 * Copyright (c) 1996, 1998 The NetBSD Foundation, Inc.
5
 * All rights reserved.
6
 *
7
 * This code is derived from software contributed to The NetBSD Foundation
8
 * by Jason R. Thorpe.
9
 *
10
 * Redistribution and use in source and binary forms, with or without
11
 * modification, are permitted provided that the following conditions
12
 * are met:
13
 * 1. Redistributions of source code must retain the above copyright
14
 *    notice, this list of conditions and the following disclaimer.
15
 * 2. Redistributions in binary form must reproduce the above copyright
16
 *    notice, this list of conditions and the following disclaimer in the
17
 *    documentation and/or other materials provided with the distribution.
18
 *
19
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29
 * POSSIBILITY OF SUCH DAMAGE.
30
 */
31
32
#ifndef _SYS_EXTENT_H_
33
#define _SYS_EXTENT_H_
34
35
#include <sys/queue.h>
36
#include <sys/mutex.h>
37
#include <sys/condvar.h>
38
39
struct extent_region {
40
        LIST_ENTRY(extent_region) er_link;        /* link in region list */
41
        u_long         er_start;                /* start of region */
42
        u_long        er_end;                        /* end of region */
43
        int        er_flags;                /* misc. flags */
44
};
45
46
/* er_flags */
47
#define ER_ALLOC        0x01        /* region descriptor dynamically allocated */
48
49
struct extent {
50
        const char *ex_name;                /* name of extent */
51
        kmutex_t ex_lock;                /* lock on this extent */
52
        kcondvar_t ex_cv;                /* synchronization */
53
                                        /* allocated regions in extent */
54
        LIST_HEAD(, extent_region) ex_regions;
55
        u_long        ex_start;                /* start of extent */
56
        u_long        ex_end;                        /* end of extent */
57
        int        ex_flags;                /* misc. information */
58
};
59
60
struct extent_fixed {
61
        struct extent        fex_extent;        /* MUST BE FIRST */
62
                                        /* freelist of region descriptors */
63
        LIST_HEAD(, extent_region) fex_freelist;
64
        void *                fex_storage;        /* storage space for descriptors */
65
        size_t                fex_storagesize; /* size of storage space */
66
};
67
68
/* ex_flags; for internal use only */
69
#define EXF_FIXED        0x01                /* extent uses fixed storage */
70
#define EXF_NOCOALESCE        0x02                /* coalescing of regions not allowed */
71
#define EXF_FLWANTED        0x08                /* someone asleep on freelist */
72
73
#define EXF_BITS        "\20\4FLWANTED\2NOCOALESCE\1FIXED"
74
75
/* misc. flags passed to extent functions */
76
#define EX_NOWAIT        0x00                /* not safe to sleep */
77
#define EX_WAITOK        0x01                /* safe to sleep */
78
#define EX_FAST                0x02                /* take first fit in extent_alloc() */
79
#define EX_CATCH        0x04                /* catch signals while sleeping */
80
#define EX_NOCOALESCE        0x08                /* create a non-coalescing extent */
81
#define EX_MALLOCOK        0x10                /* safe to call kmem_alloc() */
82
#define EX_WAITSPACE        0x20                /* wait for space to become free */
83
#define EX_BOUNDZERO        0x40                /* boundary lines start at 0 */
84
85
/*
86
 * Special place holders for "alignment" and "boundary" arguments,
87
 * in the event the caller doesn't wish to use those features.
88
 */
89
#define EX_NOALIGN        1                /* don't do alignment */
90
#define EX_NOBOUNDARY        0                /* don't do boundary checking */
91
92
#if defined(_KERNEL) || defined(_EXTENT_TESTING)
93
#define EXTENT_FIXED_STORAGE_SIZE(_nregions)                \
94
        (ALIGN(sizeof(struct extent_fixed)) +                \
95
        ((ALIGN(sizeof(struct extent_region))) *        \
96
         (_nregions)))
97
98
struct        extent *extent_create(const char *, u_long, u_long,
99
            void *, size_t, int);
100
void        extent_destroy(struct extent *);
101
int        extent_alloc_subregion1(struct extent *, u_long, u_long,
102
            u_long, u_long, u_long, u_long, int, u_long *);
103
int        extent_alloc_subregion(struct extent *, u_long, u_long,
104
            u_long, u_long, u_long, int, u_long *);
105
int        extent_alloc_region(struct extent *, u_long, u_long, int);
106
int        extent_alloc1(struct extent *, u_long, u_long, u_long, u_long, int,
107
            u_long *);
108
int        extent_alloc(struct extent *, u_long, u_long, u_long, int, u_long *);
109
int        extent_free(struct extent *, u_long, u_long, int);
110
void        extent_print(struct extent *);
111
void        extent_init(void);
112
113
#endif /* _KERNEL || _EXTENT_TESTING */
114
115
#endif /* ! _SYS_EXTENT_H_ */