1/* 2 * Bitmap Module 3 * 4 * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com> 5 * 6 * Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h 7 * 8 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. 9 * See the COPYING.LIB file in the top-level directory. 10 */ 11 12#ifndef BITMAP_H 13#define BITMAP_H 14 15#include "qemu-common.h" 16#include "qemu/bitops.h" 17 18/* 19 * The available bitmap operations and their rough meaning in the 20 * case that the bitmap is a single unsigned long are thus: 21 * 22 * Note that nbits should be always a compile time evaluable constant. 23 * Otherwise many inlines will generate horrible code. 24 * 25 * bitmap_zero(dst, nbits) *dst = 0UL 26 * bitmap_fill(dst, nbits) *dst = ~0UL 27 * bitmap_copy(dst, src, nbits) *dst = *src 28 * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 29 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 30 * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 31 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) 32 * bitmap_complement(dst, src, nbits) *dst = ~(*src) 33 * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal? 34 * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap? 35 * bitmap_empty(src, nbits) Are all bits zero in *src? 36 * bitmap_full(src, nbits) Are all bits set in *src? 37 * bitmap_set(dst, pos, nbits) Set specified bit area 38 * bitmap_clear(dst, pos, nbits) Clear specified bit area 39 * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area 40 */ 41 42/* 43 * Also the following operations apply to bitmaps. 44 * 45 * set_bit(bit, addr) *addr |= bit 46 * clear_bit(bit, addr) *addr &= ~bit 47 * change_bit(bit, addr) *addr ^= bit 48 * test_bit(bit, addr) Is bit set in *addr? 49 * test_and_set_bit(bit, addr) Set bit and return old value 50 * test_and_clear_bit(bit, addr) Clear bit and return old value 51 * test_and_change_bit(bit, addr) Change bit and return old value 52 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr 53 * find_first_bit(addr, nbits) Position first set bit in *addr 54 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit 55 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit 56 */ 57 58#define BITMAP_LAST_WORD_MASK(nbits) \ 59 ( \ 60 ((nbits) % BITS_PER_LONG) ? \ 61 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \ 62 ) 63 64#define DECLARE_BITMAP(name,bits) \ 65 unsigned long name[BITS_TO_LONGS(bits)] 66 67#define small_nbits(nbits) \ 68 ((nbits) <= BITS_PER_LONG) 69 70int slow_bitmap_empty(const unsigned long *bitmap, int bits); 71int slow_bitmap_full(const unsigned long *bitmap, int bits); 72int slow_bitmap_equal(const unsigned long *bitmap1, 73 const unsigned long *bitmap2, int bits); 74void slow_bitmap_complement(unsigned long *dst, const unsigned long *src, 75 int bits); 76void slow_bitmap_shift_right(unsigned long *dst, 77 const unsigned long *src, int shift, int bits); 78void slow_bitmap_shift_left(unsigned long *dst, 79 const unsigned long *src, int shift, int bits); 80int slow_bitmap_and(unsigned long *dst, const unsigned long *bitmap1, 81 const unsigned long *bitmap2, int bits); 82void slow_bitmap_or(unsigned long *dst, const unsigned long *bitmap1, 83 const unsigned long *bitmap2, int bits); 84void slow_bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, 85 const unsigned long *bitmap2, int bits); 86int slow_bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, 87 const unsigned long *bitmap2, int bits); 88int slow_bitmap_intersects(const unsigned long *bitmap1, 89 const unsigned long *bitmap2, int bits); 90 91static inline unsigned long *bitmap_new(int nbits) 92{ 93 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 94 return g_malloc0(len); 95} 96 97static inline void bitmap_zero(unsigned long *dst, int nbits) 98{ 99 if (small_nbits(nbits)) { 100 *dst = 0UL; 101 } else { 102 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 103 memset(dst, 0, len); 104 } 105} 106 107static inline void bitmap_fill(unsigned long *dst, int nbits) 108{ 109 size_t nlongs = BITS_TO_LONGS(nbits); 110 if (!small_nbits(nbits)) { 111 int len = (nlongs - 1) * sizeof(unsigned long); 112 memset(dst, 0xff, len); 113 } 114 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits); 115} 116 117static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, 118 int nbits) 119{ 120 if (small_nbits(nbits)) { 121 *dst = *src; 122 } else { 123 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 124 memcpy(dst, src, len); 125 } 126} 127 128static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, 129 const unsigned long *src2, int nbits) 130{ 131 if (small_nbits(nbits)) { 132 return (*dst = *src1 & *src2) != 0; 133 } 134 return slow_bitmap_and(dst, src1, src2, nbits); 135} 136 137static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, 138 const unsigned long *src2, int nbits) 139{ 140 if (small_nbits(nbits)) { 141 *dst = *src1 | *src2; 142 } else { 143 slow_bitmap_or(dst, src1, src2, nbits); 144 } 145} 146 147static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, 148 const unsigned long *src2, int nbits) 149{ 150 if (small_nbits(nbits)) { 151 *dst = *src1 ^ *src2; 152 } else { 153 slow_bitmap_xor(dst, src1, src2, nbits); 154 } 155} 156 157static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, 158 const unsigned long *src2, int nbits) 159{ 160 if (small_nbits(nbits)) { 161 return (*dst = *src1 & ~(*src2)) != 0; 162 } 163 return slow_bitmap_andnot(dst, src1, src2, nbits); 164} 165 166static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, 167 int nbits) 168{ 169 if (small_nbits(nbits)) { 170 *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits); 171 } else { 172 slow_bitmap_complement(dst, src, nbits); 173 } 174} 175 176static inline int bitmap_equal(const unsigned long *src1, 177 const unsigned long *src2, int nbits) 178{ 179 if (small_nbits(nbits)) { 180 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); 181 } else { 182 return slow_bitmap_equal(src1, src2, nbits); 183 } 184} 185 186static inline int bitmap_empty(const unsigned long *src, int nbits) 187{ 188 if (small_nbits(nbits)) { 189 return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); 190 } else { 191 return slow_bitmap_empty(src, nbits); 192 } 193} 194 195static inline int bitmap_full(const unsigned long *src, int nbits) 196{ 197 if (small_nbits(nbits)) { 198 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); 199 } else { 200 return slow_bitmap_full(src, nbits); 201 } 202} 203 204static inline int bitmap_intersects(const unsigned long *src1, 205 const unsigned long *src2, int nbits) 206{ 207 if (small_nbits(nbits)) { 208 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; 209 } else { 210 return slow_bitmap_intersects(src1, src2, nbits); 211 } 212} 213 214void bitmap_set(unsigned long *map, int i, int len); 215void bitmap_clear(unsigned long *map, int start, int nr); 216unsigned long bitmap_find_next_zero_area(unsigned long *map, 217 unsigned long size, 218 unsigned long start, 219 unsigned int nr, 220 unsigned long align_mask); 221 222#endif /* BITMAP_H */ 223