usr/src/uts/common/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 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30
  31 #ifndef _SYS_BITMAP_H
  32 #define _SYS_BITMAP_H
  33
  34 #pragma ident   "%Z%%M% %I%     %E% SMI"
  35
  36 #ifdef  __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 #include <sys/feature_tests.h>
  41 #if defined(__GNUC__) && defined(_ASM_INLINES) && \
  42         (defined(__i386) || defined(__amd64))
  43 #include <asm/bitmap.h>
  44 #endif
  45
  46 /*
  47  * Operations on bitmaps of arbitrary size
  48  * A bitmap is a vector of 1 or more ulong_t's.
  49  * The user of the package is responsible for range checks and keeping
  50  * track of sizes.
  51  */
  52
  53 #ifdef _LP64
  54 #define BT_ULSHIFT      6 /* log base 2 of BT_NBIPUL, to extract word index */
  55 #define BT_ULSHIFT32    5 /* log base 2 of BT_NBIPUL, to extract word index */
  56 #else
  57 #define BT_ULSHIFT      5 /* log base 2 of BT_NBIPUL, to extract word index */
  58 #endif
  59
  60 #define BT_NBIPUL       (1 << BT_ULSHIFT)       /* n bits per ulong_t */
  61 #define BT_ULMASK       (BT_NBIPUL - 1)         /* to extract bit index */
  62
  63 #ifdef _LP64
  64 #define BT_NBIPUL32     (1 << BT_ULSHIFT32)     /* n bits per ulong_t */
  65 #define BT_ULMASK32     (BT_NBIPUL32 - 1)       /* to extract bit index */
  66 #define BT_ULMAXMASK    0xffffffffffffffff      /* used by bt_getlowbit */
  67 #else
  68 #define BT_ULMAXMASK    0xffffffff
  69 #endif
  70
  71 /*
  72  * bitmap is a ulong_t *, bitindex an index_t
  73  *
  74  * The macros BT_WIM and BT_BIW internal; there is no need
  75  * for users of this package to use them.
  76  */
  77
  78 /*
  79  * word in map
  80  */
  81 #define BT_WIM(bitmap, bitindex) \
  82         ((bitmap)[(bitindex) >> BT_ULSHIFT])
  83 /*
  84  * bit in word
  85  */
  86 #define BT_BIW(bitindex) \
  87         (1UL << ((bitindex) & BT_ULMASK))
  88
  89 #ifdef _LP64
  90 #define BT_WIM32(bitmap, bitindex) \
  91         ((bitmap)[(bitindex) >> BT_ULSHIFT32])
  92
  93 #define BT_BIW32(bitindex) \
  94         (1UL << ((bitindex) & BT_ULMASK32))
  95 #endif
  96
  97 /*
  98  * These are public macros
  99  *
 100  * BT_BITOUL == n bits to n ulong_t's
 101  */
 102 #define BT_BITOUL(nbits) \
 103         (((nbits) + BT_NBIPUL - 1l) / BT_NBIPUL)
 104 #define BT_SIZEOFMAP(nbits) \
 105         (BT_BITOUL(nbits) * sizeof (ulong_t))
 106 #define BT_TEST(bitmap, bitindex) \
 107         ((BT_WIM((bitmap), (bitindex)) & BT_BIW(bitindex)) ? 1 : 0)
 108 #define BT_SET(bitmap, bitindex) \
 109         { BT_WIM((bitmap), (bitindex)) |= BT_BIW(bitindex); }
 110 #define BT_CLEAR(bitmap, bitindex) \
 111         { BT_WIM((bitmap), (bitindex)) &= ~BT_BIW(bitindex); }
 112
 113 #ifdef _LP64
 114 #define BT_BITOUL32(nbits) \
 115         (((nbits) + BT_NBIPUL32 - 1l) / BT_NBIPUL32)
 116 #define BT_SIZEOFMAP32(nbits) \
 117         (BT_BITOUL32(nbits) * sizeof (uint_t))
 118 #define BT_TEST32(bitmap, bitindex) \
 119         ((BT_WIM32((bitmap), (bitindex)) & BT_BIW32(bitindex)) ? 1 : 0)
 120 #define BT_SET32(bitmap, bitindex) \
 121         { BT_WIM32((bitmap), (bitindex)) |= BT_BIW32(bitindex); }
 122 #define BT_CLEAR32(bitmap, bitindex) \
 123         { BT_WIM32((bitmap), (bitindex)) &= ~BT_BIW32(bitindex); }
 124 #endif /* _LP64 */
 125
 126
 127 /*
 128  * BIT_ONLYONESET is a private macro not designed for bitmaps of
 129  * arbitrary size.  u must be an unsigned integer/long.  It returns
 130  * true if one and only one bit is set in u.
 131  */
 132 #define BIT_ONLYONESET(u) \
 133         ((((u) == 0) ? 0 : ((u) & ((u) - 1)) == 0))
 134
 135 #if defined(_KERNEL) && !defined(_ASM)
 136 #include <sys/atomic.h>
 137
 138 /*
 139  * return next available bit index from map with specified number of bits
 140  */
 141 extern index_t  bt_availbit(ulong_t *bitmap, size_t nbits);
 142 /*
 143  * find the highest order bit that is on, and is within or below
 144  * the word specified by wx
 145  */
 146 extern int      bt_gethighbit(ulong_t *mapp, int wx);
 147 extern int      bt_range(ulong_t *bitmap, size_t *pos1, size_t *pos2,
 148                         size_t end_pos);
 149 /*
 150  * Find highest and lowest one bit set.
 151  *      Returns bit number + 1 of bit that is set, otherwise returns 0.
 152  * Low order bit is 0, high order bit is 31.
 153  */
 154 extern int      highbit(ulong_t);
 155 extern int      lowbit(ulong_t);
 156 extern int      bt_getlowbit(ulong_t *bitmap, size_t start, size_t stop);
 157 extern void     bt_copy(ulong_t *, ulong_t *, ulong_t);
 158
 159 /*
 160  * find the parity
 161  */
 162 extern int      odd_parity(ulong_t);
 163
 164 /*
 165  * Atomically set/clear bits
 166  * Atomic exclusive operations will set "result" to "-1"
 167  * if the bit is already set/cleared. "result" will be set
 168  * to 0 otherwise.
 169  */
 170 #define BT_ATOMIC_SET(bitmap, bitindex) \
 171         { atomic_or_long(&(BT_WIM(bitmap, bitindex)), BT_BIW(bitindex)); }
 172 #define BT_ATOMIC_CLEAR(bitmap, bitindex) \
 173         { atomic_and_long(&(BT_WIM(bitmap, bitindex)), ~BT_BIW(bitindex)); }
 174
 175 #define BT_ATOMIC_SET_EXCL(bitmap, bitindex, result) \
 176         { result = atomic_set_long_excl(&(BT_WIM(bitmap, bitindex)),    \
 177             (bitindex) % BT_NBIPUL); }
 178 #define BT_ATOMIC_CLEAR_EXCL(bitmap, bitindex, result) \
 179         { result = atomic_clear_long_excl(&(BT_WIM(bitmap, bitindex)),  \
 180             (bitindex) % BT_NBIPUL); }
 181
 182 /*
 183  * Extracts bits between index h (high, inclusive) and l (low, exclusive) from
 184  * u, which must be an unsigned integer.
 185  */
 186 #define BITX(u, h, l)   (((u) >> (l)) & ((1LU << ((h) - (l) + 1LU)) - 1LU))
 187
 188 #endif  /* _KERNEL && !_ASM */
 189
 190 #ifdef  __cplusplus
 191 }
 192 #endif
 193
 194 #endif  /* _SYS_BITMAP_H */