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git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - include/linux/bitmap.h
1 #ifndef __LINUX_BITMAP_H
2 #define __LINUX_BITMAP_H
6 #include <linux/types.h>
7 #include <linux/bitops.h>
8 #include <linux/string.h>
11 * bitmaps provide bit arrays that consume one or more unsigned
12 * longs. The bitmap interface and available operations are listed
15 * Function implementations generic to all architectures are in
16 * lib/bitmap.c. Functions implementations that are architecture
17 * specific are in various include/asm-<arch>/bitops.h headers
18 * and other arch/<arch> specific files.
20 * See lib/bitmap.c for more details.
24 * The available bitmap operations and their rough meaning in the
25 * case that the bitmap is a single unsigned long are thus:
27 * Note that nbits should be always a compile time evaluable constant.
28 * Otherwise many inlines will generate horrible code.
30 * bitmap_zero(dst, nbits) *dst = 0UL
31 * bitmap_fill(dst, nbits) *dst = ~0UL
32 * bitmap_copy(dst, src, nbits) *dst = *src
33 * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
34 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
35 * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
36 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
37 * bitmap_complement(dst, src, nbits) *dst = ~(*src)
38 * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
39 * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
40 * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
41 * bitmap_empty(src, nbits) Are all bits zero in *src?
42 * bitmap_full(src, nbits) Are all bits set in *src?
43 * bitmap_weight(src, nbits) Hamming Weight: number set bits
44 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
45 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
46 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
47 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
48 * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
49 * bitmap_parse(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
50 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
51 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
52 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
53 * bitmap_release_region(bitmap, pos, order) Free specified bit region
54 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
58 * Also the following operations in asm/bitops.h apply to bitmaps.
60 * set_bit(bit, addr) *addr |= bit
61 * clear_bit(bit, addr) *addr &= ~bit
62 * change_bit(bit, addr) *addr ^= bit
63 * test_bit(bit, addr) Is bit set in *addr?
64 * test_and_set_bit(bit, addr) Set bit and return old value
65 * test_and_clear_bit(bit, addr) Clear bit and return old value
66 * test_and_change_bit(bit, addr) Change bit and return old value
67 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
68 * find_first_bit(addr, nbits) Position first set bit in *addr
69 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
70 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
74 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
75 * to declare an array named 'name' of just enough unsigned longs to
76 * contain all bit positions from 0 to 'bits' - 1.
80 * lib/bitmap.c provides these functions:
83 extern int __bitmap_empty(const unsigned long *bitmap
, int bits
);
84 extern int __bitmap_full(const unsigned long *bitmap
, int bits
);
85 extern int __bitmap_equal(const unsigned long *bitmap1
,
86 const unsigned long *bitmap2
, int bits
);
87 extern void __bitmap_complement(unsigned long *dst
, const unsigned long *src
,
89 extern void __bitmap_shift_right(unsigned long *dst
,
90 const unsigned long *src
, int shift
, int bits
);
91 extern void __bitmap_shift_left(unsigned long *dst
,
92 const unsigned long *src
, int shift
, int bits
);
93 extern void __bitmap_and(unsigned long *dst
, const unsigned long *bitmap1
,
94 const unsigned long *bitmap2
, int bits
);
95 extern void __bitmap_or(unsigned long *dst
, const unsigned long *bitmap1
,
96 const unsigned long *bitmap2
, int bits
);
97 extern void __bitmap_xor(unsigned long *dst
, const unsigned long *bitmap1
,
98 const unsigned long *bitmap2
, int bits
);
99 extern void __bitmap_andnot(unsigned long *dst
, const unsigned long *bitmap1
,
100 const unsigned long *bitmap2
, int bits
);
101 extern int __bitmap_intersects(const unsigned long *bitmap1
,
102 const unsigned long *bitmap2
, int bits
);
103 extern int __bitmap_subset(const unsigned long *bitmap1
,
104 const unsigned long *bitmap2
, int bits
);
105 extern int __bitmap_weight(const unsigned long *bitmap
, int bits
);
107 extern int bitmap_scnprintf(char *buf
, unsigned int len
,
108 const unsigned long *src
, int nbits
);
109 extern int bitmap_parse(const char __user
*ubuf
, unsigned int ulen
,
110 unsigned long *dst
, int nbits
);
111 extern int bitmap_scnlistprintf(char *buf
, unsigned int len
,
112 const unsigned long *src
, int nbits
);
113 extern int bitmap_parselist(const char *buf
, unsigned long *maskp
,
115 extern void bitmap_remap(unsigned long *dst
, const unsigned long *src
,
116 const unsigned long *old
, const unsigned long *new, int bits
);
117 extern int bitmap_bitremap(int oldbit
,
118 const unsigned long *old
, const unsigned long *new, int bits
);
119 extern int bitmap_find_free_region(unsigned long *bitmap
, int bits
, int order
);
120 extern void bitmap_release_region(unsigned long *bitmap
, int pos
, int order
);
121 extern int bitmap_allocate_region(unsigned long *bitmap
, int pos
, int order
);
123 #define BITMAP_LAST_WORD_MASK(nbits) \
125 ((nbits) % BITS_PER_LONG) ? \
126 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
129 static inline void bitmap_zero(unsigned long *dst
, int nbits
)
131 if (nbits
<= BITS_PER_LONG
)
134 int len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
139 static inline void bitmap_fill(unsigned long *dst
, int nbits
)
141 size_t nlongs
= BITS_TO_LONGS(nbits
);
143 int len
= (nlongs
- 1) * sizeof(unsigned long);
144 memset(dst
, 0xff, len
);
146 dst
[nlongs
- 1] = BITMAP_LAST_WORD_MASK(nbits
);
149 static inline void bitmap_copy(unsigned long *dst
, const unsigned long *src
,
152 if (nbits
<= BITS_PER_LONG
)
155 int len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
156 memcpy(dst
, src
, len
);
160 static inline void bitmap_and(unsigned long *dst
, const unsigned long *src1
,
161 const unsigned long *src2
, int nbits
)
163 if (nbits
<= BITS_PER_LONG
)
164 *dst
= *src1
& *src2
;
166 __bitmap_and(dst
, src1
, src2
, nbits
);
169 static inline void bitmap_or(unsigned long *dst
, const unsigned long *src1
,
170 const unsigned long *src2
, int nbits
)
172 if (nbits
<= BITS_PER_LONG
)
173 *dst
= *src1
| *src2
;
175 __bitmap_or(dst
, src1
, src2
, nbits
);
178 static inline void bitmap_xor(unsigned long *dst
, const unsigned long *src1
,
179 const unsigned long *src2
, int nbits
)
181 if (nbits
<= BITS_PER_LONG
)
182 *dst
= *src1
^ *src2
;
184 __bitmap_xor(dst
, src1
, src2
, nbits
);
187 static inline void bitmap_andnot(unsigned long *dst
, const unsigned long *src1
,
188 const unsigned long *src2
, int nbits
)
190 if (nbits
<= BITS_PER_LONG
)
191 *dst
= *src1
& ~(*src2
);
193 __bitmap_andnot(dst
, src1
, src2
, nbits
);
196 static inline void bitmap_complement(unsigned long *dst
, const unsigned long *src
,
199 if (nbits
<= BITS_PER_LONG
)
200 *dst
= ~(*src
) & BITMAP_LAST_WORD_MASK(nbits
);
202 __bitmap_complement(dst
, src
, nbits
);
205 static inline int bitmap_equal(const unsigned long *src1
,
206 const unsigned long *src2
, int nbits
)
208 if (nbits
<= BITS_PER_LONG
)
209 return ! ((*src1
^ *src2
) & BITMAP_LAST_WORD_MASK(nbits
));
211 return __bitmap_equal(src1
, src2
, nbits
);
214 static inline int bitmap_intersects(const unsigned long *src1
,
215 const unsigned long *src2
, int nbits
)
217 if (nbits
<= BITS_PER_LONG
)
218 return ((*src1
& *src2
) & BITMAP_LAST_WORD_MASK(nbits
)) != 0;
220 return __bitmap_intersects(src1
, src2
, nbits
);
223 static inline int bitmap_subset(const unsigned long *src1
,
224 const unsigned long *src2
, int nbits
)
226 if (nbits
<= BITS_PER_LONG
)
227 return ! ((*src1
& ~(*src2
)) & BITMAP_LAST_WORD_MASK(nbits
));
229 return __bitmap_subset(src1
, src2
, nbits
);
232 static inline int bitmap_empty(const unsigned long *src
, int nbits
)
234 if (nbits
<= BITS_PER_LONG
)
235 return ! (*src
& BITMAP_LAST_WORD_MASK(nbits
));
237 return __bitmap_empty(src
, nbits
);
240 static inline int bitmap_full(const unsigned long *src
, int nbits
)
242 if (nbits
<= BITS_PER_LONG
)
243 return ! (~(*src
) & BITMAP_LAST_WORD_MASK(nbits
));
245 return __bitmap_full(src
, nbits
);
248 static inline int bitmap_weight(const unsigned long *src
, int nbits
)
250 if (nbits
<= BITS_PER_LONG
)
251 return hweight_long(*src
& BITMAP_LAST_WORD_MASK(nbits
));
252 return __bitmap_weight(src
, nbits
);
255 static inline void bitmap_shift_right(unsigned long *dst
,
256 const unsigned long *src
, int n
, int nbits
)
258 if (nbits
<= BITS_PER_LONG
)
261 __bitmap_shift_right(dst
, src
, n
, nbits
);
264 static inline void bitmap_shift_left(unsigned long *dst
,
265 const unsigned long *src
, int n
, int nbits
)
267 if (nbits
<= BITS_PER_LONG
)
268 *dst
= (*src
<< n
) & BITMAP_LAST_WORD_MASK(nbits
);
270 __bitmap_shift_left(dst
, src
, n
, nbits
);
273 #endif /* __ASSEMBLY__ */
275 #endif /* __LINUX_BITMAP_H */