xref: /titanic_41/usr/src/uts/common/sys/bitmap.h (revision 8b6220d73c6a079b62251e38103a523c41ee541a)
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
39 extern "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  */
143 extern 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  */
148 extern int	bt_gethighbit(ulong_t *mapp, int wx);
149 extern 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  */
156 extern int	highbit(ulong_t);
157 extern int	highbit64(uint64_t);
158 extern int	lowbit(ulong_t);
159 extern int	bt_getlowbit(ulong_t *bitmap, size_t start, size_t stop);
160 extern void	bt_copy(ulong_t *, ulong_t *, ulong_t);
161 
162 /*
163  * find the parity
164  */
165 extern 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_ulong(&(BT_WIM(bitmap, bitindex)), BT_BIW(bitindex)); }
175 #define	BT_ATOMIC_CLEAR(bitmap, bitindex) \
176 	{ atomic_and_ulong(&(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