1/* $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
39struct 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
49struct 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
60struct 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
98struct extent *extent_create(const char *, u_long, u_long,
99 void *, size_t, int);
100void extent_destroy(struct extent *);
101int extent_alloc_subregion1(struct extent *, u_long, u_long,
102 u_long, u_long, u_long, u_long, int, u_long *);
103int extent_alloc_subregion(struct extent *, u_long, u_long,
104 u_long, u_long, u_long, int, u_long *);
105int extent_alloc_region(struct extent *, u_long, u_long, int);
106int extent_alloc1(struct extent *, u_long, u_long, u_long, u_long, int,
107 u_long *);
108int extent_alloc(struct extent *, u_long, u_long, u_long, int, u_long *);
109int extent_free(struct extent *, u_long, u_long, int);
110void extent_print(struct extent *);
111void extent_init(void);
112
113#endif /* _KERNEL || _EXTENT_TESTING */
114
115#endif /* ! _SYS_EXTENT_H_ */
116