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_scnprintf(buf, len, src, nbits) Print bitmap src to buf
56 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
57 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
58 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
59 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
60 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
61 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
62 * bitmap_release_region(bitmap, pos, order) Free specified bit region
63 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
64 * bitmap_print_to_pagebuf(list, buf, mask, nbits) Print bitmap src as list/hex
68 * Also the following operations in asm/bitops.h apply to bitmaps.
70 * set_bit(bit, addr) *addr |= bit
71 * clear_bit(bit, addr) *addr &= ~bit
72 * change_bit(bit, addr) *addr ^= bit
73 * test_bit(bit, addr) Is bit set in *addr?
74 * test_and_set_bit(bit, addr) Set bit and return old value
75 * test_and_clear_bit(bit, addr) Clear bit and return old value
76 * test_and_change_bit(bit, addr) Change bit and return old value
77 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
78 * find_first_bit(addr, nbits) Position first set bit in *addr
79 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
80 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
84 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
85 * to declare an array named 'name' of just enough unsigned longs to
86 * contain all bit positions from 0 to 'bits' - 1.
90 * lib/bitmap.c provides these functions:
93 extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
94 extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
95 extern int __bitmap_equal(const unsigned long *bitmap1,
96 const unsigned long *bitmap2, unsigned int nbits);
97 extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
99 extern void __bitmap_shift_right(unsigned long *dst,
100 const unsigned long *src, int shift, int bits);
101 extern void __bitmap_shift_left(unsigned long *dst,
102 const unsigned long *src, int shift, int bits);
103 extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
104 const unsigned long *bitmap2, unsigned int nbits);
105 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
106 const unsigned long *bitmap2, unsigned int nbits);
107 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
108 const unsigned long *bitmap2, unsigned int nbits);
109 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
110 const unsigned long *bitmap2, unsigned int nbits);
111 extern int __bitmap_intersects(const unsigned long *bitmap1,
112 const unsigned long *bitmap2, unsigned int nbits);
113 extern int __bitmap_subset(const unsigned long *bitmap1,
114 const unsigned long *bitmap2, unsigned int nbits);
115 extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
117 extern void bitmap_set(unsigned long *map, unsigned int start, int len);
118 extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
120 extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
124 unsigned long align_mask,
125 unsigned long align_offset);
128 * bitmap_find_next_zero_area - find a contiguous aligned zero area
129 * @map: The address to base the search on
130 * @size: The bitmap size in bits
131 * @start: The bitnumber to start searching at
132 * @nr: The number of zeroed bits we're looking for
133 * @align_mask: Alignment mask for zero area
135 * The @align_mask should be one less than a power of 2; the effect is that
136 * the bit offset of all zero areas this function finds is multiples of that
137 * power of 2. A @align_mask of 0 means no alignment is required.
139 static inline unsigned long
140 bitmap_find_next_zero_area(unsigned long *map,
144 unsigned long align_mask)
146 return bitmap_find_next_zero_area_off(map, size, start, nr,
150 extern int bitmap_scnprintf(char *buf, unsigned int len,
151 const unsigned long *src, int nbits);
152 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
153 unsigned long *dst, int nbits);
154 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
155 unsigned long *dst, int nbits);
156 extern int bitmap_scnlistprintf(char *buf, unsigned int len,
157 const unsigned long *src, int nbits);
158 extern int bitmap_parselist(const char *buf, unsigned long *maskp,
160 extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
161 unsigned long *dst, int nbits);
162 extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
163 const unsigned long *old, const unsigned long *new, unsigned int nbits);
164 extern int bitmap_bitremap(int oldbit,
165 const unsigned long *old, const unsigned long *new, int bits);
166 extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
167 const unsigned long *relmap, unsigned int bits);
168 extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
169 unsigned int sz, unsigned int nbits);
170 extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
171 extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
172 extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
174 extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
176 #define bitmap_copy_le bitmap_copy
178 extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
179 extern int bitmap_print_to_pagebuf(bool list, char *buf,
180 const unsigned long *maskp, int nmaskbits);
182 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))
183 #define BITMAP_LAST_WORD_MASK(nbits) \
185 ((nbits) % BITS_PER_LONG) ? \
186 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
189 #define small_const_nbits(nbits) \
190 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
192 static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
194 if (small_const_nbits(nbits))
197 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
202 static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
204 unsigned int nlongs = BITS_TO_LONGS(nbits);
205 if (!small_const_nbits(nbits)) {
206 unsigned int len = (nlongs - 1) * sizeof(unsigned long);
207 memset(dst, 0xff, len);
209 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
212 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
215 if (small_const_nbits(nbits))
218 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
219 memcpy(dst, src, len);
223 static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
224 const unsigned long *src2, unsigned int nbits)
226 if (small_const_nbits(nbits))
227 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
228 return __bitmap_and(dst, src1, src2, nbits);
231 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
232 const unsigned long *src2, unsigned int nbits)
234 if (small_const_nbits(nbits))
235 *dst = *src1 | *src2;
237 __bitmap_or(dst, src1, src2, nbits);
240 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
241 const unsigned long *src2, unsigned int nbits)
243 if (small_const_nbits(nbits))
244 *dst = *src1 ^ *src2;
246 __bitmap_xor(dst, src1, src2, nbits);
249 static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
250 const unsigned long *src2, unsigned int nbits)
252 if (small_const_nbits(nbits))
253 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
254 return __bitmap_andnot(dst, src1, src2, nbits);
257 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
260 if (small_const_nbits(nbits))
263 __bitmap_complement(dst, src, nbits);
266 static inline int bitmap_equal(const unsigned long *src1,
267 const unsigned long *src2, unsigned int nbits)
269 if (small_const_nbits(nbits))
270 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
272 return __bitmap_equal(src1, src2, nbits);
275 static inline int bitmap_intersects(const unsigned long *src1,
276 const unsigned long *src2, unsigned int nbits)
278 if (small_const_nbits(nbits))
279 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
281 return __bitmap_intersects(src1, src2, nbits);
284 static inline int bitmap_subset(const unsigned long *src1,
285 const unsigned long *src2, unsigned int nbits)
287 if (small_const_nbits(nbits))
288 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
290 return __bitmap_subset(src1, src2, nbits);
293 static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
295 if (small_const_nbits(nbits))
296 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
298 return __bitmap_empty(src, nbits);
301 static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
303 if (small_const_nbits(nbits))
304 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
306 return __bitmap_full(src, nbits);
309 static inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
311 if (small_const_nbits(nbits))
312 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
313 return __bitmap_weight(src, nbits);
316 static inline void bitmap_shift_right(unsigned long *dst,
317 const unsigned long *src, int n, int nbits)
319 if (small_const_nbits(nbits))
320 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> n;
322 __bitmap_shift_right(dst, src, n, nbits);
325 static inline void bitmap_shift_left(unsigned long *dst,
326 const unsigned long *src, int n, int nbits)
328 if (small_const_nbits(nbits))
329 *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
331 __bitmap_shift_left(dst, src, n, nbits);
334 static inline int bitmap_parse(const char *buf, unsigned int buflen,
335 unsigned long *maskp, int nmaskbits)
337 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
340 #endif /* __ASSEMBLY__ */
342 #endif /* __LINUX_BITMAP_H */