xref: /openbsd/sys/sys/extent.h (revision baaa8a4a)
1 /*	$OpenBSD: extent.h,v 1.15 2024/01/19 22:12:24 kettenis Exp $	*/
2 /*	$NetBSD: extent.h,v 1.6 1997/10/09 07:43:05 jtc Exp $	*/
3 
4 /*-
5  * Copyright (c) 1996 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jason R. Thorpe.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifndef _SYS_EXTENT_H_
34 #define _SYS_EXTENT_H_
35 
36 #include <sys/queue.h>
37 
38 struct extent_region {
39 	LIST_ENTRY(extent_region) er_link;	/* link in region list */
40 	u_long 	er_start;		/* start of region */
41 	u_long	er_end;			/* end of region */
42 	int	er_flags;		/* misc. flags */
43 };
44 
45 /* er_flags */
46 #define ER_ALLOC	0x01	/* region descriptor dynamically allocated */
47 #define ER_DISCARD	0x02	/* discard region descriptor after use */
48 
49 struct extent {
50 	char	*ex_name;		/* name of extent */
51 					/* allocated regions in extent */
52 	LIST_HEAD(, extent_region) ex_regions;
53 	u_long	ex_start;		/* start of extent */
54 	u_long	ex_end;			/* end of extent */
55 	int	ex_mtype;		/* memory type */
56 	int	ex_flags;		/* misc. information */
57 
58 	LIST_ENTRY(extent) ex_link;
59 };
60 
61 struct extent_fixed {
62 	struct extent	fex_extent;	/* MUST BE FIRST */
63 					/* freelist of region descriptors */
64 	LIST_HEAD(, extent_region) fex_freelist;
65 	caddr_t		fex_storage;	/* storage space for descriptors */
66 	size_t		fex_storagesize; /* size of storage space */
67 };
68 
69 /* ex_flags; for internal use only */
70 #define EXF_FIXED	0x01		/* extent uses fixed storage */
71 #define EXF_NOCOALESCE	0x02		/* coalescing of regions not allowed */
72 #define EXF_WANTED	0x04		/* someone asleep on extent */
73 #define EXF_FLWANTED	0x08		/* someone asleep on freelist */
74 
75 #define EXF_BITS	"\20\4FLWANTED\3WANTED\2NOCOALESCE\1FIXED"
76 
77 /* misc. flags passed to extent functions */
78 #define EX_NOWAIT	0x0000		/* not safe to sleep */
79 #define EX_WAITOK	0x0001		/* safe to sleep */
80 #define EX_FAST		0x0002		/* take first fit in extent_alloc() */
81 #define EX_CATCH	0x0004		/* catch signals while sleeping */
82 #define EX_NOCOALESCE	0x0008		/* create a non-coalescing extent */
83 #define EX_MALLOCOK	0x0010		/* safe to call malloc() */
84 #define EX_WAITSPACE	0x0020		/* wait for space to become free */
85 #define EX_BOUNDZERO	0x0040		/* boundary lines start at 0 */
86 #define EX_CONFLICTOK	0x0080		/* allow conflicts */
87 #define EX_FILLED	0x0100		/* create a filled extent */
88 
89 /*
90  * Special place holders for "alignment" and "boundary" arguments,
91  * in the event the caller doesn't wish to use those features.
92  */
93 #define EX_NOALIGN	1		/* don't do alignment */
94 #define EX_NOBOUNDARY	0		/* don't do boundary checking */
95 
96 #if defined(_KERNEL) || defined(_EXTENT_TESTING)
97 #define EXTENT_FIXED_STORAGE_SIZE(_nregions)		\
98 	(ALIGN(sizeof(struct extent_fixed)) +		\
99 	((ALIGN(sizeof(struct extent_region))) *	\
100 	 (_nregions)))
101 
102 void extent_print_all(void);
103 
104 struct	extent *extent_create(char *, u_long, u_long, int,
105 	    caddr_t, size_t, int);
106 void	extent_destroy(struct extent *);
107 int	extent_alloc_subregion(struct extent *, u_long, u_long,
108 	    u_long, u_long, u_long, u_long, int, u_long *);
109 int	extent_alloc_subregion_with_descr(struct extent *, u_long, u_long,
110 	    u_long, u_long, u_long, u_long, int, struct extent_region *,
111 	    u_long *);
112 int	extent_alloc_region(struct extent *, u_long, u_long, int);
113 int	extent_alloc_region_with_descr(struct extent *, u_long, u_long,
114 	    int, struct extent_region *);
115 int	extent_free(struct extent *, u_long, u_long, int);
116 void	extent_print(struct extent *);
117 
118 /* Simple case of extent_alloc_subregion() */
119 #define extent_alloc(_ex, _size, _alignment, _skew, _boundary, \
120 		_flags, _result) \
121 	extent_alloc_subregion((_ex), (_ex)->ex_start, (_ex)->ex_end,  \
122 	(_size), (_alignment), (_skew), (_boundary), (_flags), (_result))
123 
124 /* Simple case of extent_alloc_subregion_with_descr() */
125 #define extent_alloc_with_descr(_ex, _size, _alignment, _skew, _boundary, \
126 		_flags, _region, _result) \
127 	extent_alloc_subregion_with_descr((_ex), (_ex)->ex_start, \
128 	(_ex)->ex_end, (_size), (_alignment), (_skew), (_boundary), \
129 	(_flags), (_region), (_result))
130 #endif /* _KERNEL || _EXTENT_TESTING */
131 
132 #endif /* ! _SYS_EXTENT_H_ */
133