bitmap.h revision 265740 
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*
28 * Copyright (c) 2014 by Delphix. All rights reserved.
29 */
30
31/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
32/*	  All Rights Reserved  	*/
33
34
35#ifndef _SYS_BITMAP_H
36#define	_SYS_BITMAP_H
37
38#ifdef	__cplusplus
39extern "C" {
40#endif
41
42#include <sys/feature_tests.h>
43#if defined(__GNUC__) && defined(_ASM_INLINES) && \
44	(defined(__i386) || defined(__amd64))
45#include <asm/bitmap.h>
46#endif
47
48/*
49 * Operations on bitmaps of arbitrary size
50 * A bitmap is a vector of 1 or more ulong_t's.
51 * The user of the package is responsible for range checks and keeping
52 * track of sizes.
53 */
54
55#ifdef _LP64
56#define	BT_ULSHIFT	6 /* log base 2 of BT_NBIPUL, to extract word index */
57#define	BT_ULSHIFT32	5 /* log base 2 of BT_NBIPUL, to extract word index */
58#else
59#define	BT_ULSHIFT	5 /* log base 2 of BT_NBIPUL, to extract word index */
60#endif
61
62#define	BT_NBIPUL	(1 << BT_ULSHIFT)	/* n bits per ulong_t */
63#define	BT_ULMASK	(BT_NBIPUL - 1)		/* to extract bit index */
64
65#ifdef _LP64
66#define	BT_NBIPUL32	(1 << BT_ULSHIFT32)	/* n bits per ulong_t */
67#define	BT_ULMASK32	(BT_NBIPUL32 - 1)	/* to extract bit index */
68#define	BT_ULMAXMASK	0xffffffffffffffff	/* used by bt_getlowbit */
69#else
70#define	BT_ULMAXMASK	0xffffffff
71#endif
72
73/*
74 * bitmap is a ulong_t *, bitindex an index_t
75 *
76 * The macros BT_WIM and BT_BIW internal; there is no need
77 * for users of this package to use them.
78 */
79
80/*
81 * word in map
82 */
83#define	BT_WIM(bitmap, bitindex) \
84	((bitmap)[(bitindex) >> BT_ULSHIFT])
85/*
86 * bit in word
87 */
88#define	BT_BIW(bitindex) \
89	(1UL << ((bitindex) & BT_ULMASK))
90
91#ifdef _LP64
92#define	BT_WIM32(bitmap, bitindex) \
93	((bitmap)[(bitindex) >> BT_ULSHIFT32])
94
95#define	BT_BIW32(bitindex) \
96	(1UL << ((bitindex) & BT_ULMASK32))
97#endif
98
99/*
100 * These are public macros
101 *
102 * BT_BITOUL == n bits to n ulong_t's
103 */
104#define	BT_BITOUL(nbits) \
105	(((nbits) + BT_NBIPUL - 1l) / BT_NBIPUL)
106#define	BT_SIZEOFMAP(nbits) \
107	(BT_BITOUL(nbits) * sizeof (ulong_t))
108#define	BT_TEST(bitmap, bitindex) \
109	((BT_WIM((bitmap), (bitindex)) & BT_BIW(bitindex)) ? 1 : 0)
110#define	BT_SET(bitmap, bitindex) \
111	{ BT_WIM((bitmap), (bitindex)) |= BT_BIW(bitindex); }
112#define	BT_CLEAR(bitmap, bitindex) \
113	{ BT_WIM((bitmap), (bitindex)) &= ~BT_BIW(bitindex); }
114
115#ifdef _LP64
116#define	BT_BITOUL32(nbits) \
117	(((nbits) + BT_NBIPUL32 - 1l) / BT_NBIPUL32)
118#define	BT_SIZEOFMAP32(nbits) \
119	(BT_BITOUL32(nbits) * sizeof (uint_t))
120#define	BT_TEST32(bitmap, bitindex) \
121	((BT_WIM32((bitmap), (bitindex)) & BT_BIW32(bitindex)) ? 1 : 0)
122#define	BT_SET32(bitmap, bitindex) \
123	{ BT_WIM32((bitmap), (bitindex)) |= BT_BIW32(bitindex); }
124#define	BT_CLEAR32(bitmap, bitindex) \
125	{ BT_WIM32((bitmap), (bitindex)) &= ~BT_BIW32(bitindex); }
126#endif /* _LP64 */
127
128
129/*
130 * BIT_ONLYONESET is a private macro not designed for bitmaps of
131 * arbitrary size.  u must be an unsigned integer/long.  It returns
132 * true if one and only one bit is set in u.
133 */
134#define	BIT_ONLYONESET(u) \
135	((((u) == 0) ? 0 : ((u) & ((u) - 1)) == 0))
136
137#if defined(_KERNEL) && !defined(_ASM)
138#include <sys/atomic.h>
139
140/*
141 * return next available bit index from map with specified number of bits
142 */
143extern index_t	bt_availbit(ulong_t *bitmap, size_t nbits);
144/*
145 * find the highest order bit that is on, and is within or below
146 * the word specified by wx
147 */
148extern int	bt_gethighbit(ulong_t *mapp, int wx);
149extern int	bt_range(ulong_t *bitmap, size_t *pos1, size_t *pos2,
150			size_t end_pos);
151/*
152 * Find highest and lowest one bit set.
153 *	Returns bit number + 1 of bit that is set, otherwise returns 0.
154 * Low order bit is 0, high order bit is 31.
155 */
156extern int	highbit(ulong_t);
157extern int	highbit64(uint64_t);
158extern int	lowbit(ulong_t);
159extern int	bt_getlowbit(ulong_t *bitmap, size_t start, size_t stop);
160extern void	bt_copy(ulong_t *, ulong_t *, ulong_t);
161
162/*
163 * find the parity
164 */
165extern int	odd_parity(ulong_t);
166
167/*
168 * Atomically set/clear bits
169 * Atomic exclusive operations will set "result" to "-1"
170 * if the bit is already set/cleared. "result" will be set
171 * to 0 otherwise.
172 */
173#define	BT_ATOMIC_SET(bitmap, bitindex) \
174	{ atomic_or_long(&(BT_WIM(bitmap, bitindex)), BT_BIW(bitindex)); }
175#define	BT_ATOMIC_CLEAR(bitmap, bitindex) \
176	{ atomic_and_long(&(BT_WIM(bitmap, bitindex)), ~BT_BIW(bitindex)); }
177
178#define	BT_ATOMIC_SET_EXCL(bitmap, bitindex, result) \
179	{ result = atomic_set_long_excl(&(BT_WIM(bitmap, bitindex)),	\
180	    (bitindex) % BT_NBIPUL); }
181#define	BT_ATOMIC_CLEAR_EXCL(bitmap, bitindex, result) \
182	{ result = atomic_clear_long_excl(&(BT_WIM(bitmap, bitindex)),	\
183	    (bitindex) % BT_NBIPUL); }
184
185/*
186 * Extracts bits between index h (high, inclusive) and l (low, exclusive) from
187 * u, which must be an unsigned integer.
188 */
189#define	BITX(u, h, l)	(((u) >> (l)) & ((1LU << ((h) - (l) + 1LU)) - 1LU))
190
191#endif	/* _KERNEL && !_ASM */
192
193#ifdef	__cplusplus
194}
195#endif
196
197#endif	/* _SYS_BITMAP_H */
198