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>
9 #include <linux/kernel.h>
12 * bitmaps provide bit arrays that consume one or more unsigned
13 * longs. The bitmap interface and available operations are listed
16 * Function implementations generic to all architectures are in
17 * lib/bitmap.c. Functions implementations that are architecture
18 * specific are in various include/asm-<arch>/bitops.h headers
19 * and other arch/<arch> specific files.
21 * See lib/bitmap.c for more details.
25 * The available bitmap operations and their rough meaning in the
26 * case that the bitmap is a single unsigned long are thus:
28 * Note that nbits should be always a compile time evaluable constant.
29 * Otherwise many inlines will generate horrible code.
31 * bitmap_zero(dst, nbits) *dst = 0UL
32 * bitmap_fill(dst, nbits) *dst = ~0UL
33 * bitmap_copy(dst, src, nbits) *dst = *src
34 * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
35 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
36 * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
37 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
38 * bitmap_complement(dst, src, nbits) *dst = ~(*src)
39 * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
40 * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
41 * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
42 * bitmap_empty(src, nbits) Are all bits zero in *src?
43 * bitmap_full(src, nbits) Are all bits set in *src?
44 * bitmap_weight(src, nbits) Hamming Weight: number set bits
45 * bitmap_set(dst, pos, nbits) Set specified bit area
46 * bitmap_clear(dst, pos, nbits) Clear specified bit area
47 * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
48 * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above
49 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
50 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
51 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
52 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
53 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
54 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
55 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
56 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
57 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
58 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
59 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
60 * bitmap_release_region(bitmap, pos, order) Free specified bit region
61 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
62 * bitmap_from_u32array(dst, nbits, buf, nwords) *dst = *buf (nwords 32b words)
63 * bitmap_to_u32array(buf, nwords, src, nbits) *buf = *dst (nwords 32b words)
67 * Also the following operations in asm/bitops.h apply to bitmaps.
69 * set_bit(bit, addr) *addr |= bit
70 * clear_bit(bit, addr) *addr &= ~bit
71 * change_bit(bit, addr) *addr ^= bit
72 * test_bit(bit, addr) Is bit set in *addr?
73 * test_and_set_bit(bit, addr) Set bit and return old value
74 * test_and_clear_bit(bit, addr) Clear bit and return old value
75 * test_and_change_bit(bit, addr) Change bit and return old value
76 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
77 * find_first_bit(addr, nbits) Position first set bit in *addr
78 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
79 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
83 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
84 * to declare an array named 'name' of just enough unsigned longs to
85 * contain all bit positions from 0 to 'bits' - 1.
89 * lib/bitmap.c provides these functions:
92 extern int __bitmap_empty(const unsigned long *bitmap
, unsigned int nbits
);
93 extern int __bitmap_full(const unsigned long *bitmap
, unsigned int nbits
);
94 extern int __bitmap_equal(const unsigned long *bitmap1
,
95 const unsigned long *bitmap2
, unsigned int nbits
);
96 extern void __bitmap_complement(unsigned long *dst
, const unsigned long *src
,
98 extern void __bitmap_shift_right(unsigned long *dst
, const unsigned long *src
,
99 unsigned int shift
, unsigned int nbits
);
100 extern void __bitmap_shift_left(unsigned long *dst
, const unsigned long *src
,
101 unsigned int shift
, unsigned int nbits
);
102 extern int __bitmap_and(unsigned long *dst
, const unsigned long *bitmap1
,
103 const unsigned long *bitmap2
, unsigned int nbits
);
104 extern void __bitmap_or(unsigned long *dst
, const unsigned long *bitmap1
,
105 const unsigned long *bitmap2
, unsigned int nbits
);
106 extern void __bitmap_xor(unsigned long *dst
, const unsigned long *bitmap1
,
107 const unsigned long *bitmap2
, unsigned int nbits
);
108 extern int __bitmap_andnot(unsigned long *dst
, const unsigned long *bitmap1
,
109 const unsigned long *bitmap2
, unsigned int nbits
);
110 extern int __bitmap_intersects(const unsigned long *bitmap1
,
111 const unsigned long *bitmap2
, unsigned int nbits
);
112 extern int __bitmap_subset(const unsigned long *bitmap1
,
113 const unsigned long *bitmap2
, unsigned int nbits
);
114 extern int __bitmap_weight(const unsigned long *bitmap
, unsigned int nbits
);
115 extern void __bitmap_set(unsigned long *map
, unsigned int start
, int len
);
116 extern void __bitmap_clear(unsigned long *map
, unsigned int start
, int len
);
118 extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map
,
122 unsigned long align_mask
,
123 unsigned long align_offset
);
126 * bitmap_find_next_zero_area - find a contiguous aligned zero area
127 * @map: The address to base the search on
128 * @size: The bitmap size in bits
129 * @start: The bitnumber to start searching at
130 * @nr: The number of zeroed bits we're looking for
131 * @align_mask: Alignment mask for zero area
133 * The @align_mask should be one less than a power of 2; the effect is that
134 * the bit offset of all zero areas this function finds is multiples of that
135 * power of 2. A @align_mask of 0 means no alignment is required.
137 static inline unsigned long
138 bitmap_find_next_zero_area(unsigned long *map
,
142 unsigned long align_mask
)
144 return bitmap_find_next_zero_area_off(map
, size
, start
, nr
,
148 extern int __bitmap_parse(const char *buf
, unsigned int buflen
, int is_user
,
149 unsigned long *dst
, int nbits
);
150 extern int bitmap_parse_user(const char __user
*ubuf
, unsigned int ulen
,
151 unsigned long *dst
, int nbits
);
152 extern int bitmap_parselist(const char *buf
, unsigned long *maskp
,
154 extern int bitmap_parselist_user(const char __user
*ubuf
, unsigned int ulen
,
155 unsigned long *dst
, int nbits
);
156 extern void bitmap_remap(unsigned long *dst
, const unsigned long *src
,
157 const unsigned long *old
, const unsigned long *new, unsigned int nbits
);
158 extern int bitmap_bitremap(int oldbit
,
159 const unsigned long *old
, const unsigned long *new, int bits
);
160 extern void bitmap_onto(unsigned long *dst
, const unsigned long *orig
,
161 const unsigned long *relmap
, unsigned int bits
);
162 extern void bitmap_fold(unsigned long *dst
, const unsigned long *orig
,
163 unsigned int sz
, unsigned int nbits
);
164 extern int bitmap_find_free_region(unsigned long *bitmap
, unsigned int bits
, int order
);
165 extern void bitmap_release_region(unsigned long *bitmap
, unsigned int pos
, int order
);
166 extern int bitmap_allocate_region(unsigned long *bitmap
, unsigned int pos
, int order
);
167 extern unsigned int bitmap_from_u32array(unsigned long *bitmap
,
170 unsigned int nwords
);
171 extern unsigned int bitmap_to_u32array(u32
*buf
,
173 const unsigned long *bitmap
,
176 extern void bitmap_copy_le(unsigned long *dst
, const unsigned long *src
, unsigned int nbits
);
178 #define bitmap_copy_le bitmap_copy
180 extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap
, unsigned int ord
, unsigned int nbits
);
181 extern int bitmap_print_to_pagebuf(bool list
, char *buf
,
182 const unsigned long *maskp
, int nmaskbits
);
184 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
185 #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
187 #define small_const_nbits(nbits) \
188 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
190 static inline void bitmap_zero(unsigned long *dst
, unsigned int nbits
)
192 if (small_const_nbits(nbits
))
195 unsigned int len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
200 static inline void bitmap_fill(unsigned long *dst
, unsigned int nbits
)
202 unsigned int nlongs
= BITS_TO_LONGS(nbits
);
203 if (!small_const_nbits(nbits
)) {
204 unsigned int len
= (nlongs
- 1) * sizeof(unsigned long);
205 memset(dst
, 0xff, len
);
207 dst
[nlongs
- 1] = BITMAP_LAST_WORD_MASK(nbits
);
210 static inline void bitmap_copy(unsigned long *dst
, const unsigned long *src
,
213 if (small_const_nbits(nbits
))
216 unsigned int len
= BITS_TO_LONGS(nbits
) * sizeof(unsigned long);
217 memcpy(dst
, src
, len
);
221 static inline int bitmap_and(unsigned long *dst
, const unsigned long *src1
,
222 const unsigned long *src2
, unsigned int nbits
)
224 if (small_const_nbits(nbits
))
225 return (*dst
= *src1
& *src2
& BITMAP_LAST_WORD_MASK(nbits
)) != 0;
226 return __bitmap_and(dst
, src1
, src2
, nbits
);
229 static inline void bitmap_or(unsigned long *dst
, const unsigned long *src1
,
230 const unsigned long *src2
, unsigned int nbits
)
232 if (small_const_nbits(nbits
))
233 *dst
= *src1
| *src2
;
235 __bitmap_or(dst
, src1
, src2
, nbits
);
238 static inline void bitmap_xor(unsigned long *dst
, const unsigned long *src1
,
239 const unsigned long *src2
, unsigned int nbits
)
241 if (small_const_nbits(nbits
))
242 *dst
= *src1
^ *src2
;
244 __bitmap_xor(dst
, src1
, src2
, nbits
);
247 static inline int bitmap_andnot(unsigned long *dst
, const unsigned long *src1
,
248 const unsigned long *src2
, unsigned int nbits
)
250 if (small_const_nbits(nbits
))
251 return (*dst
= *src1
& ~(*src2
) & BITMAP_LAST_WORD_MASK(nbits
)) != 0;
252 return __bitmap_andnot(dst
, src1
, src2
, nbits
);
255 static inline void bitmap_complement(unsigned long *dst
, const unsigned long *src
,
258 if (small_const_nbits(nbits
))
261 __bitmap_complement(dst
, src
, nbits
);
264 static inline int bitmap_equal(const unsigned long *src1
,
265 const unsigned long *src2
, unsigned int nbits
)
267 if (small_const_nbits(nbits
))
268 return !((*src1
^ *src2
) & BITMAP_LAST_WORD_MASK(nbits
));
269 if (__builtin_constant_p(nbits
& 7) && IS_ALIGNED(nbits
, 8))
270 return !memcmp(src1
, src2
, nbits
/ 8);
271 return __bitmap_equal(src1
, src2
, nbits
);
274 static inline int bitmap_intersects(const unsigned long *src1
,
275 const unsigned long *src2
, unsigned int nbits
)
277 if (small_const_nbits(nbits
))
278 return ((*src1
& *src2
) & BITMAP_LAST_WORD_MASK(nbits
)) != 0;
280 return __bitmap_intersects(src1
, src2
, nbits
);
283 static inline int bitmap_subset(const unsigned long *src1
,
284 const unsigned long *src2
, unsigned int nbits
)
286 if (small_const_nbits(nbits
))
287 return ! ((*src1
& ~(*src2
)) & BITMAP_LAST_WORD_MASK(nbits
));
289 return __bitmap_subset(src1
, src2
, nbits
);
292 static inline int bitmap_empty(const unsigned long *src
, unsigned nbits
)
294 if (small_const_nbits(nbits
))
295 return ! (*src
& BITMAP_LAST_WORD_MASK(nbits
));
297 return find_first_bit(src
, nbits
) == nbits
;
300 static inline int bitmap_full(const unsigned long *src
, unsigned int nbits
)
302 if (small_const_nbits(nbits
))
303 return ! (~(*src
) & BITMAP_LAST_WORD_MASK(nbits
));
305 return find_first_zero_bit(src
, nbits
) == nbits
;
308 static __always_inline
int bitmap_weight(const unsigned long *src
, unsigned int nbits
)
310 if (small_const_nbits(nbits
))
311 return hweight_long(*src
& BITMAP_LAST_WORD_MASK(nbits
));
312 return __bitmap_weight(src
, nbits
);
315 static __always_inline
void bitmap_set(unsigned long *map
, unsigned int start
,
318 if (__builtin_constant_p(nbits
) && nbits
== 1)
319 __set_bit(start
, map
);
320 else if (__builtin_constant_p(start
& 7) && IS_ALIGNED(start
, 8) &&
321 __builtin_constant_p(nbits
& 7) && IS_ALIGNED(nbits
, 8))
322 memset((char *)map
+ start
/ 8, 0xff, nbits
/ 8);
324 __bitmap_set(map
, start
, nbits
);
327 static __always_inline
void bitmap_clear(unsigned long *map
, unsigned int start
,
330 if (__builtin_constant_p(nbits
) && nbits
== 1)
331 __clear_bit(start
, map
);
332 else if (__builtin_constant_p(start
& 7) && IS_ALIGNED(start
, 8) &&
333 __builtin_constant_p(nbits
& 7) && IS_ALIGNED(nbits
, 8))
334 memset((char *)map
+ start
/ 8, 0, nbits
/ 8);
336 __bitmap_clear(map
, start
, nbits
);
339 static inline void bitmap_shift_right(unsigned long *dst
, const unsigned long *src
,
340 unsigned int shift
, int nbits
)
342 if (small_const_nbits(nbits
))
343 *dst
= (*src
& BITMAP_LAST_WORD_MASK(nbits
)) >> shift
;
345 __bitmap_shift_right(dst
, src
, shift
, nbits
);
348 static inline void bitmap_shift_left(unsigned long *dst
, const unsigned long *src
,
349 unsigned int shift
, unsigned int nbits
)
351 if (small_const_nbits(nbits
))
352 *dst
= (*src
<< shift
) & BITMAP_LAST_WORD_MASK(nbits
);
354 __bitmap_shift_left(dst
, src
, shift
, nbits
);
357 static inline int bitmap_parse(const char *buf
, unsigned int buflen
,
358 unsigned long *maskp
, int nmaskbits
)
360 return __bitmap_parse(buf
, buflen
, 0, maskp
, nmaskbits
);
364 * bitmap_from_u64 - Check and swap words within u64.
365 * @mask: source bitmap
366 * @dst: destination bitmap
368 * In 32-bit Big Endian kernel, when using (u32 *)(&val)[*]
369 * to read u64 mask, we will get the wrong word.
370 * That is "(u32 *)(&val)[0]" gets the upper 32 bits,
371 * but we expect the lower 32-bits of u64.
373 static inline void bitmap_from_u64(unsigned long *dst
, u64 mask
)
375 dst
[0] = mask
& ULONG_MAX
;
377 if (sizeof(mask
) > sizeof(unsigned long))
381 #endif /* __ASSEMBLY__ */
383 #endif /* __LINUX_BITMAP_H */