4 * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com>
6 * Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h
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.
15 #include "qemu-common.h"
16 #include "qemu/bitops.h"
19 * The available bitmap operations and their rough meaning in the
20 * case that the bitmap is a single unsigned long are thus:
22 * Note that nbits should be always a compile time evaluable constant.
23 * Otherwise many inlines will generate horrible code.
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
43 * Also the following operations apply to bitmaps.
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
58 #define BITMAP_LAST_WORD_MASK(nbits) \
60 ((nbits) % BITS_PER_LONG) ? \
61 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
64 #define DECLARE_BITMAP(name,bits) \
65 unsigned long name[BITS_TO_LONGS(bits)]
67 #define small_nbits(nbits) \
68 ((nbits) <= BITS_PER_LONG)
70 int slow_bitmap_empty(const unsigned long *bitmap
, long bits
);
71 int slow_bitmap_full(const unsigned long *bitmap
, long bits
);
72 int slow_bitmap_equal(const unsigned long *bitmap1
,
73 const unsigned long *bitmap2
, long bits
);
74 void slow_bitmap_complement(unsigned long *dst
, const unsigned long *src
,
76 void slow_bitmap_shift_right(unsigned long *dst
,
77 const unsigned long *src
, int shift
, long bits
);
78 void slow_bitmap_shift_left(unsigned long *dst
,
79 const unsigned long *src
, int shift
, long bits
);
80 int slow_bitmap_and(unsigned long *dst
, const unsigned long *bitmap1
,
81 const unsigned long *bitmap2
, long bits
);
82 void slow_bitmap_or(unsigned long *dst
, const unsigned long *bitmap1
,
83 const unsigned long *bitmap2
, long bits
);
84 void slow_bitmap_xor(unsigned long *dst
, const unsigned long *bitmap1
,
85 const unsigned long *bitmap2
, long bits
);
86 int slow_bitmap_andnot(unsigned long *dst
, const unsigned long *bitmap1
,
87 const unsigned long *bitmap2
, long bits
);
88 int slow_bitmap_intersects(const unsigned long *bitmap1
,
89 const unsigned long *bitmap2
, long bits
);
91 static inline unsigned long *bitmap_try_new(long nbits
)
93 long len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
94 return g_try_malloc0(len
);
97 static inline unsigned long *bitmap_new(long nbits
)
99 unsigned long *ptr
= bitmap_try_new(nbits
);
106 static inline void bitmap_zero(unsigned long *dst
, long nbits
)
108 if (small_nbits(nbits
)) {
111 long len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
116 static inline void bitmap_fill(unsigned long *dst
, long nbits
)
118 size_t nlongs
= BITS_TO_LONGS(nbits
);
119 if (!small_nbits(nbits
)) {
120 long len
= (nlongs
- 1) * sizeof(unsigned long);
121 memset(dst
, 0xff, len
);
123 dst
[nlongs
- 1] = BITMAP_LAST_WORD_MASK(nbits
);
126 static inline void bitmap_copy(unsigned long *dst
, const unsigned long *src
,
129 if (small_nbits(nbits
)) {
132 long len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
133 memcpy(dst
, src
, len
);
137 static inline int bitmap_and(unsigned long *dst
, const unsigned long *src1
,
138 const unsigned long *src2
, long nbits
)
140 if (small_nbits(nbits
)) {
141 return (*dst
= *src1
& *src2
) != 0;
143 return slow_bitmap_and(dst
, src1
, src2
, nbits
);
146 static inline void bitmap_or(unsigned long *dst
, const unsigned long *src1
,
147 const unsigned long *src2
, long nbits
)
149 if (small_nbits(nbits
)) {
150 *dst
= *src1
| *src2
;
152 slow_bitmap_or(dst
, src1
, src2
, nbits
);
156 static inline void bitmap_xor(unsigned long *dst
, const unsigned long *src1
,
157 const unsigned long *src2
, long nbits
)
159 if (small_nbits(nbits
)) {
160 *dst
= *src1
^ *src2
;
162 slow_bitmap_xor(dst
, src1
, src2
, nbits
);
166 static inline int bitmap_andnot(unsigned long *dst
, const unsigned long *src1
,
167 const unsigned long *src2
, long nbits
)
169 if (small_nbits(nbits
)) {
170 return (*dst
= *src1
& ~(*src2
)) != 0;
172 return slow_bitmap_andnot(dst
, src1
, src2
, nbits
);
175 static inline void bitmap_complement(unsigned long *dst
,
176 const unsigned long *src
,
179 if (small_nbits(nbits
)) {
180 *dst
= ~(*src
) & BITMAP_LAST_WORD_MASK(nbits
);
182 slow_bitmap_complement(dst
, src
, nbits
);
186 static inline int bitmap_equal(const unsigned long *src1
,
187 const unsigned long *src2
, long nbits
)
189 if (small_nbits(nbits
)) {
190 return ! ((*src1
^ *src2
) & BITMAP_LAST_WORD_MASK(nbits
));
192 return slow_bitmap_equal(src1
, src2
, nbits
);
196 static inline int bitmap_empty(const unsigned long *src
, long nbits
)
198 if (small_nbits(nbits
)) {
199 return ! (*src
& BITMAP_LAST_WORD_MASK(nbits
));
201 return slow_bitmap_empty(src
, nbits
);
205 static inline int bitmap_full(const unsigned long *src
, long nbits
)
207 if (small_nbits(nbits
)) {
208 return ! (~(*src
) & BITMAP_LAST_WORD_MASK(nbits
));
210 return slow_bitmap_full(src
, nbits
);
214 static inline int bitmap_intersects(const unsigned long *src1
,
215 const unsigned long *src2
, long nbits
)
217 if (small_nbits(nbits
)) {
218 return ((*src1
& *src2
) & BITMAP_LAST_WORD_MASK(nbits
)) != 0;
220 return slow_bitmap_intersects(src1
, src2
, nbits
);
224 void bitmap_set(unsigned long *map
, long i
, long len
);
225 void bitmap_clear(unsigned long *map
, long start
, long nr
);
226 unsigned long bitmap_find_next_zero_area(unsigned long *map
,
230 unsigned long align_mask
);
232 static inline unsigned long *bitmap_zero_extend(unsigned long *old
,
233 long old_nbits
, long new_nbits
)
235 long new_len
= BITS_TO_LONGS(new_nbits
) * sizeof(unsigned long);
236 unsigned long *new = g_realloc(old
, new_len
);
237 bitmap_clear(new, old_nbits
, new_nbits
- old_nbits
);
241 #endif /* BITMAP_H */