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1#ifndef __LINUX_BITMAP_H
2#define __LINUX_BITMAP_H
3
4#ifndef __ASSEMBLY__
5
6#include <linux/types.h>
7#include <linux/bitops.h>
8#include <linux/string.h>
9#include <linux/kernel.h>
10
11/*
12 * bitmaps provide bit arrays that consume one or more unsigned
13 * longs. The bitmap interface and available operations are listed
14 * here, in bitmap.h
15 *
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.
20 *
21 * See lib/bitmap.c for more details.
22 */
23
24/*
25 * The available bitmap operations and their rough meaning in the
26 * case that the bitmap is a single unsigned long are thus:
27 *
28 * Note that nbits should be always a compile time evaluable constant.
29 * Otherwise many inlines will generate horrible code.
30 *
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_shift_right(dst, src, n, nbits) *dst = *src >> n
46 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
47 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
48 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
49 * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
50 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
51 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
52 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
53 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
54 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
55 * bitmap_release_region(bitmap, pos, order) Free specified bit region
56 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
57 */
58
59/*
60 * Also the following operations in asm/bitops.h apply to bitmaps.
61 *
62 * set_bit(bit, addr) *addr |= bit
63 * clear_bit(bit, addr) *addr &= ~bit
64 * change_bit(bit, addr) *addr ^= bit
65 * test_bit(bit, addr) Is bit set in *addr?
66 * test_and_set_bit(bit, addr) Set bit and return old value
67 * test_and_clear_bit(bit, addr) Clear bit and return old value
68 * test_and_change_bit(bit, addr) Change bit and return old value
69 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
70 * find_first_bit(addr, nbits) Position first set bit in *addr
71 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
72 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
73 */
74
75/*
76 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
77 * to declare an array named 'name' of just enough unsigned longs to
78 * contain all bit positions from 0 to 'bits' - 1.
79 */
80
81/*
82 * lib/bitmap.c provides these functions:
83 */
84
85extern int __bitmap_empty(const unsigned long *bitmap, int bits);
86extern int __bitmap_full(const unsigned long *bitmap, int bits);
87extern int __bitmap_equal(const unsigned long *bitmap1,
88 const unsigned long *bitmap2, int bits);
89extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
90 int bits);
91extern void __bitmap_shift_right(unsigned long *dst,
92 const unsigned long *src, int shift, int bits);
93extern void __bitmap_shift_left(unsigned long *dst,
94 const unsigned long *src, int shift, int bits);
95extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
96 const unsigned long *bitmap2, int bits);
97extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
98 const unsigned long *bitmap2, int bits);
99extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
100 const unsigned long *bitmap2, int bits);
101extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
102 const unsigned long *bitmap2, int bits);
103extern int __bitmap_intersects(const unsigned long *bitmap1,
104 const unsigned long *bitmap2, int bits);
105extern int __bitmap_subset(const unsigned long *bitmap1,
106 const unsigned long *bitmap2, int bits);
107extern int __bitmap_weight(const unsigned long *bitmap, int bits);
108
109extern int bitmap_scnprintf(char *buf, unsigned int len,
110 const unsigned long *src, int nbits);
111extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
112 unsigned long *dst, int nbits);
113extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
114 unsigned long *dst, int nbits);
115extern int bitmap_scnlistprintf(char *buf, unsigned int len,
116 const unsigned long *src, int nbits);
117extern int bitmap_parselist(const char *buf, unsigned long *maskp,
118 int nmaskbits);
119extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
120 const unsigned long *old, const unsigned long *new, int bits);
121extern int bitmap_bitremap(int oldbit,
122 const unsigned long *old, const unsigned long *new, int bits);
123extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
124extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
125extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
126
127#define BITMAP_LAST_WORD_MASK(nbits) \
128( \
129 ((nbits) % BITS_PER_LONG) ? \
130 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
131)
132
133static inline void bitmap_zero(unsigned long *dst, int nbits)
134{
135 if (nbits <= BITS_PER_LONG)
136 *dst = 0UL;
137 else {
138 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
139 memset(dst, 0, len);
140 }
141}
142
143static inline void bitmap_fill(unsigned long *dst, int nbits)
144{
145 size_t nlongs = BITS_TO_LONGS(nbits);
146 if (nlongs > 1) {
147 int len = (nlongs - 1) * sizeof(unsigned long);
148 memset(dst, 0xff, len);
149 }
150 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
151}
152
153static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
154 int nbits)
155{
156 if (nbits <= BITS_PER_LONG)
157 *dst = *src;
158 else {
159 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
160 memcpy(dst, src, len);
161 }
162}
163
164static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
165 const unsigned long *src2, int nbits)
166{
167 if (nbits <= BITS_PER_LONG)
168 *dst = *src1 & *src2;
169 else
170 __bitmap_and(dst, src1, src2, nbits);
171}
172
173static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
174 const unsigned long *src2, int nbits)
175{
176 if (nbits <= BITS_PER_LONG)
177 *dst = *src1 | *src2;
178 else
179 __bitmap_or(dst, src1, src2, nbits);
180}
181
182static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
183 const unsigned long *src2, int nbits)
184{
185 if (nbits <= BITS_PER_LONG)
186 *dst = *src1 ^ *src2;
187 else
188 __bitmap_xor(dst, src1, src2, nbits);
189}
190
191static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
192 const unsigned long *src2, int nbits)
193{
194 if (nbits <= BITS_PER_LONG)
195 *dst = *src1 & ~(*src2);
196 else
197 __bitmap_andnot(dst, src1, src2, nbits);
198}
199
200static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
201 int nbits)
202{
203 if (nbits <= BITS_PER_LONG)
204 *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
205 else
206 __bitmap_complement(dst, src, nbits);
207}
208
209static inline int bitmap_equal(const unsigned long *src1,
210 const unsigned long *src2, int nbits)
211{
212 if (nbits <= BITS_PER_LONG)
213 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
214 else
215 return __bitmap_equal(src1, src2, nbits);
216}
217
218static inline int bitmap_intersects(const unsigned long *src1,
219 const unsigned long *src2, int nbits)
220{
221 if (nbits <= BITS_PER_LONG)
222 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
223 else
224 return __bitmap_intersects(src1, src2, nbits);
225}
226
227static inline int bitmap_subset(const unsigned long *src1,
228 const unsigned long *src2, int nbits)
229{
230 if (nbits <= BITS_PER_LONG)
231 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
232 else
233 return __bitmap_subset(src1, src2, nbits);
234}
235
236static inline int bitmap_empty(const unsigned long *src, int nbits)
237{
238 if (nbits <= BITS_PER_LONG)
239 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
240 else
241 return __bitmap_empty(src, nbits);
242}
243
244static inline int bitmap_full(const unsigned long *src, int nbits)
245{
246 if (nbits <= BITS_PER_LONG)
247 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
248 else
249 return __bitmap_full(src, nbits);
250}
251
252static inline int bitmap_weight(const unsigned long *src, int nbits)
253{
254 if (nbits <= BITS_PER_LONG)
255 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
256 return __bitmap_weight(src, nbits);
257}
258
259static inline void bitmap_shift_right(unsigned long *dst,
260 const unsigned long *src, int n, int nbits)
261{
262 if (nbits <= BITS_PER_LONG)
263 *dst = *src >> n;
264 else
265 __bitmap_shift_right(dst, src, n, nbits);
266}
267
268static inline void bitmap_shift_left(unsigned long *dst,
269 const unsigned long *src, int n, int nbits)
270{
271 if (nbits <= BITS_PER_LONG)
272 *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
273 else
274 __bitmap_shift_left(dst, src, n, nbits);
275}
276
277static inline int bitmap_parse(const char *buf, unsigned int buflen,
278 unsigned long *maskp, int nmaskbits)
279{
280 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
281}
282
283#endif /* __ASSEMBLY__ */
284
285#endif /* __LINUX_BITMAP_H */