include/sys/bitmap.h

   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 */