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  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
  30  * Copyright 2017 RackTop Systems.
  31  */
  32 
  33 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T     */
  34 /*        All Rights Reserved   */
  35 
  36 
  37 #ifndef _SYS_BITMAP_H
  38 #define _SYS_BITMAP_H
  39 
  40 #ifdef  __cplusplus
  41 extern "C" {
  42 #endif
  43 
  44 #include <sys/feature_tests.h>
  45 #if defined(__GNUC__) && defined(_ASM_INLINES) && \
  46         (defined(__i386) || defined(__amd64))
  47 #include <asm/bitmap.h>
  48 #endif
  49 
  50 /*
  51  * Operations on bitmaps of arbitrary size
  52  * A bitmap is a vector of 1 or more ulong_t's.
  53  * The user of the package is responsible for range checks and keeping
  54  * track of sizes.
  55  */
  56 
  57 #ifdef _LP64
  58 #define BT_ULSHIFT      6 /* log base 2 of BT_NBIPUL, to extract word index */
  59 #define BT_ULSHIFT32    5 /* log base 2 of BT_NBIPUL, to extract word index */
  60 #else
  61 #define BT_ULSHIFT      5 /* log base 2 of BT_NBIPUL, to extract word index */
  62 #endif
  63 
  64 #define BT_NBIPUL       (1 << BT_ULSHIFT) /* n bits per ulong_t */
  65 #define BT_ULMASK       (BT_NBIPUL - 1)         /* to extract bit index */
  66 
  67 #ifdef _LP64
  68 #define BT_NBIPUL32     (1 << BT_ULSHIFT32)       /* n bits per ulong_t */
  69 #define BT_ULMASK32     (BT_NBIPUL32 - 1)       /* to extract bit index */
  70 #define BT_ULMAXMASK    0xffffffffffffffff      /* used by bt_getlowbit */
  71 #else
  72 #define BT_ULMAXMASK    0xffffffff
  73 #endif
  74 
  75 /*
  76  * bitmap is a ulong_t *, bitindex an index_t
  77  *
  78  * The macros BT_WIM and BT_BIW internal; there is no need
  79  * for users of this package to use them.
  80  */
  81 
  82 /*
  83  * word in map
  84  */
  85 #define BT_WIM(bitmap, bitindex) \
  86         ((bitmap)[(bitindex) >> BT_ULSHIFT])
  87 /*
  88  * bit in word
  89  */
  90 #define BT_BIW(bitindex) \
  91         (1UL << ((bitindex) & BT_ULMASK))
  92 
  93 #ifdef _LP64
  94 #define BT_WIM32(bitmap, bitindex) \
  95         ((bitmap)[(bitindex) >> BT_ULSHIFT32])
  96 
  97 #define BT_BIW32(bitindex) \
  98         (1UL << ((bitindex) & BT_ULMASK32))
  99 #endif
 100 
 101 /*
 102  * These are public macros
 103  *
 104  * BT_BITOUL == n bits to n ulong_t's
 105  */
 106 #define BT_BITOUL(nbits) \
 107         (((nbits) + BT_NBIPUL - 1l) / BT_NBIPUL)
 108 #define BT_SIZEOFMAP(nbits) \
 109         (BT_BITOUL(nbits) * sizeof (ulong_t))
 110 #define BT_TEST(bitmap, bitindex) \
 111         ((BT_WIM((bitmap), (bitindex)) & BT_BIW(bitindex)) ? 1 : 0)
 112 #define BT_SET(bitmap, bitindex) \
 113         { BT_WIM((bitmap), (bitindex)) |= BT_BIW(bitindex); }
 114 #define BT_CLEAR(bitmap, bitindex) \
 115         { BT_WIM((bitmap), (bitindex)) &= ~BT_BIW(bitindex); }
 116 
 117 #ifdef _LP64
 118 #define BT_BITOUL32(nbits) \
 119         (((nbits) + BT_NBIPUL32 - 1l) / BT_NBIPUL32)
 120 #define BT_SIZEOFMAP32(nbits) \
 121         (BT_BITOUL32(nbits) * sizeof (uint_t))
 122 #define BT_TEST32(bitmap, bitindex) \
 123         ((BT_WIM32((bitmap), (bitindex)) & BT_BIW32(bitindex)) ? 1 : 0)
 124 #define BT_SET32(bitmap, bitindex) \
 125         { BT_WIM32((bitmap), (bitindex)) |= BT_BIW32(bitindex); }
 126 #define BT_CLEAR32(bitmap, bitindex) \
 127         { BT_WIM32((bitmap), (bitindex)) &= ~BT_BIW32(bitindex); }
 128 #endif /* _LP64 */
 129 
 130 
 131 /*
 132  * BIT_ONLYONESET is a private macro not designed for bitmaps of
 133  * arbitrary size.  u must be an unsigned integer/long.  It returns
 134  * true if one and only one bit is set in u.
 135  */
 136 #define BIT_ONLYONESET(u) \
 137         ((((u) == 0) ? 0 : ((u) & ((u) - 1)) == 0))
 138 
 139 #if (defined(_KERNEL) || defined(_FAKE_KERNEL)) && !defined(_ASM)
 140 #include <sys/atomic.h>
 141 
 142 /*
 143  * return next available bit index from map with specified number of bits
 144  */
 145 extern index_t  bt_availbit(ulong_t *bitmap, size_t nbits);
 146 /*
 147  * find the highest order bit that is on, and is within or below
 148  * the word specified by wx
 149  */
 150 extern int      bt_gethighbit(ulong_t *mapp, int wx);
 151 extern int      bt_range(ulong_t *bitmap, size_t *pos1, size_t *pos2,
 152                         size_t end_pos);
 153 /*
 154  * Find highest and lowest one bit set.
 155  *      Returns bit number + 1 of bit that is set, otherwise returns 0.
 156  * Low order bit is 0, high order bit is 31.
 157  */
 158 extern int      highbit(ulong_t);
 159 extern int      highbit64(uint64_t);
 160 extern int      lowbit(ulong_t);
 161 extern int      bt_getlowbit(ulong_t *bitmap, size_t start, size_t stop);
 162 extern void     bt_copy(ulong_t *, ulong_t *, ulong_t);
 163 
 164 /*
 165  * find the parity
 166  */
 167 extern int      odd_parity(ulong_t);
 168 
 169 /*
 170  * Atomically set/clear bits
 171  * Atomic exclusive operations will set "result" to "-1"
 172  * if the bit is already set/cleared. "result" will be set
 173  * to 0 otherwise.
 174  */
 175 #define BT_ATOMIC_SET(bitmap, bitindex) \
 176         { atomic_or_ulong(&(BT_WIM(bitmap, bitindex)), BT_BIW(bitindex)); }
 177 #define BT_ATOMIC_CLEAR(bitmap, bitindex) \
 178         { atomic_and_ulong(&(BT_WIM(bitmap, bitindex)), ~BT_BIW(bitindex)); }
 179 
 180 #define BT_ATOMIC_SET_EXCL(bitmap, bitindex, result) \
 181         { result = atomic_set_long_excl(&(BT_WIM(bitmap, bitindex)),        \
 182             (bitindex) % BT_NBIPUL); }
 183 #define BT_ATOMIC_CLEAR_EXCL(bitmap, bitindex, result) \
 184         { result = atomic_clear_long_excl(&(BT_WIM(bitmap, bitindex)),      \
 185             (bitindex) % BT_NBIPUL); }
 186 
 187 /*
 188  * Extracts bits between index h (high, inclusive) and l (low, exclusive) from
 189  * u, which must be an unsigned integer.
 190  */
 191 #define BITX(u, h, l)   (((u) >> (l)) & ((1LU << ((h) - (l) + 1LU)) - 1LU))
 192 
 193 #endif  /* (_KERNEL || _FAKE_KERNEL) && !_ASM */
 194 
 195 #ifdef  __cplusplus
 196 }
 197 #endif
 198 
 199 #endif  /* _SYS_BITMAP_H */