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 * Allocation and deallocation of bitmap.
90 * Provided in lib/bitmap.c to avoid circular dependency.
92 extern unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags);
93 extern unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
94 extern void bitmap_free(const unsigned long *bitmap);
97 * lib/bitmap.c provides these functions:
100 extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
101 extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
102 extern int __bitmap_equal(const unsigned long *bitmap1,
103 const unsigned long *bitmap2, unsigned int nbits);
104 extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
106 extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
107 unsigned int shift, unsigned int nbits);
108 extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
109 unsigned int shift, unsigned int nbits);
110 extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
111 const unsigned long *bitmap2, unsigned int nbits);
112 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
113 const unsigned long *bitmap2, unsigned int nbits);
114 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
115 const unsigned long *bitmap2, unsigned int nbits);
116 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
117 const unsigned long *bitmap2, unsigned int nbits);
118 extern int __bitmap_intersects(const unsigned long *bitmap1,
119 const unsigned long *bitmap2, unsigned int nbits);
120 extern int __bitmap_subset(const unsigned long *bitmap1,
121 const unsigned long *bitmap2, unsigned int nbits);
122 extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
124 extern void bitmap_set(unsigned long *map, unsigned int start, int len);
125 extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
127 extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
131 unsigned long align_mask,
132 unsigned long align_offset);
135 * bitmap_find_next_zero_area - find a contiguous aligned zero area
136 * @map: The address to base the search on
137 * @size: The bitmap size in bits
138 * @start: The bitnumber to start searching at
139 * @nr: The number of zeroed bits we're looking for
140 * @align_mask: Alignment mask for zero area
142 * The @align_mask should be one less than a power of 2; the effect is that
143 * the bit offset of all zero areas this function finds is multiples of that
144 * power of 2. A @align_mask of 0 means no alignment is required.
146 static inline unsigned long
147 bitmap_find_next_zero_area(unsigned long *map,
151 unsigned long align_mask)
153 return bitmap_find_next_zero_area_off(map, size, start, nr,
157 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
158 unsigned long *dst, int nbits);
159 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
160 unsigned long *dst, int nbits);
161 extern int bitmap_parselist(const char *buf, unsigned long *maskp,
163 extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
164 unsigned long *dst, int nbits);
165 extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
166 const unsigned long *old, const unsigned long *new, unsigned int nbits);
167 extern int bitmap_bitremap(int oldbit,
168 const unsigned long *old, const unsigned long *new, int bits);
169 extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
170 const unsigned long *relmap, unsigned int bits);
171 extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
172 unsigned int sz, unsigned int nbits);
173 extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
174 extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
175 extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
176 extern unsigned int bitmap_from_u32array(unsigned long *bitmap,
179 unsigned int nwords);
180 extern unsigned int bitmap_to_u32array(u32 *buf,
182 const unsigned long *bitmap,
185 extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
187 #define bitmap_copy_le bitmap_copy
189 extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
190 extern int bitmap_print_to_pagebuf(bool list, char *buf,
191 const unsigned long *maskp, int nmaskbits);
193 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
194 #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
197 * The static inlines below do not handle constant nbits==0 correctly,
198 * so make such users (should any ever turn up) call the out-of-line
201 #define small_const_nbits(nbits) \
202 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG && (nbits) > 0)
204 static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
206 if (small_const_nbits(nbits))
209 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
214 static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
216 unsigned int nlongs = BITS_TO_LONGS(nbits);
217 if (!small_const_nbits(nbits)) {
218 unsigned int len = (nlongs - 1) * sizeof(unsigned long);
219 memset(dst, 0xff, len);
221 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
224 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
227 if (small_const_nbits(nbits))
230 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
231 memcpy(dst, src, len);
235 static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
236 const unsigned long *src2, unsigned int nbits)
238 if (small_const_nbits(nbits))
239 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
240 return __bitmap_and(dst, src1, src2, nbits);
243 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
244 const unsigned long *src2, unsigned int nbits)
246 if (small_const_nbits(nbits))
247 *dst = *src1 | *src2;
249 __bitmap_or(dst, src1, src2, nbits);
252 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
253 const unsigned long *src2, unsigned int nbits)
255 if (small_const_nbits(nbits))
256 *dst = *src1 ^ *src2;
258 __bitmap_xor(dst, src1, src2, nbits);
261 static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
262 const unsigned long *src2, unsigned int nbits)
264 if (small_const_nbits(nbits))
265 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
266 return __bitmap_andnot(dst, src1, src2, nbits);
269 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
272 if (small_const_nbits(nbits))
275 __bitmap_complement(dst, src, nbits);
278 static inline int bitmap_equal(const unsigned long *src1,
279 const unsigned long *src2, unsigned int nbits)
281 if (small_const_nbits(nbits))
282 return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
284 if (__builtin_constant_p(nbits) && (nbits % BITS_PER_LONG) == 0)
285 return !memcmp(src1, src2, nbits / 8);
287 return __bitmap_equal(src1, src2, nbits);
290 static inline int bitmap_intersects(const unsigned long *src1,
291 const unsigned long *src2, unsigned int nbits)
293 if (small_const_nbits(nbits))
294 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
296 return __bitmap_intersects(src1, src2, nbits);
299 static inline int bitmap_subset(const unsigned long *src1,
300 const unsigned long *src2, unsigned int nbits)
302 if (small_const_nbits(nbits))
303 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
305 return __bitmap_subset(src1, src2, nbits);
308 static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
310 if (small_const_nbits(nbits))
311 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
313 return find_first_bit(src, nbits) == nbits;
316 static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
318 if (small_const_nbits(nbits))
319 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
321 return find_first_zero_bit(src, nbits) == nbits;
324 static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
326 if (small_const_nbits(nbits))
327 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
328 return __bitmap_weight(src, nbits);
331 static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
332 unsigned int shift, unsigned int nbits)
334 if (small_const_nbits(nbits))
335 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
337 __bitmap_shift_right(dst, src, shift, nbits);
340 static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
341 unsigned int shift, unsigned int nbits)
343 if (small_const_nbits(nbits))
344 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
346 __bitmap_shift_left(dst, src, shift, nbits);
349 static inline int bitmap_parse(const char *buf, unsigned int buflen,
350 unsigned long *maskp, int nmaskbits)
352 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
356 * bitmap_from_u64 - Check and swap words within u64.
357 * @mask: source bitmap
358 * @dst: destination bitmap
360 * In 32-bit Big Endian kernel, when using (u32 *)(&val)[*]
361 * to read u64 mask, we will get the wrong word.
362 * That is "(u32 *)(&val)[0]" gets the upper 32 bits,
363 * but we expect the lower 32-bits of u64.
365 static inline void bitmap_from_u64(unsigned long *dst, u64 mask)
367 dst[0] = mask & ULONG_MAX;
369 if (sizeof(mask) > sizeof(unsigned long))
373 #endif /* __ASSEMBLY__ */
375 #endif /* __LINUX_BITMAP_H */