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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
10/*
11 * bitmaps provide bit arrays that consume one or more unsigned
12 * longs. The bitmap interface and available operations are listed
13 * here, in bitmap.h
14 *
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.
19 *
20 * See lib/bitmap.c for more details.
21 */
22
23/*
24 * The available bitmap operations and their rough meaning in the
25 * case that the bitmap is a single unsigned long are thus:
26 *
27 * bitmap_zero(dst, nbits) *dst = 0UL
28 * bitmap_fill(dst, nbits) *dst = ~0UL
29 * bitmap_copy(dst, src, nbits) *dst = *src
30 * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
31 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
32 * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
33 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
34 * bitmap_complement(dst, src, nbits) *dst = ~(*src)
35 * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
36 * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
37 * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
38 * bitmap_empty(src, nbits) Are all bits zero in *src?
39 * bitmap_full(src, nbits) Are all bits set in *src?
40 * bitmap_weight(src, nbits) Hamming Weight: number set bits
41 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
42 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
43 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
44 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
45 * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
46 * bitmap_parse(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
47 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
48 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
49 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
50 * bitmap_release_region(bitmap, pos, order) Free specified bit region
51 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
52 */
53
54/*
55 * Also the following operations in asm/bitops.h apply to bitmaps.
56 *
57 * set_bit(bit, addr) *addr |= bit
58 * clear_bit(bit, addr) *addr &= ~bit
59 * change_bit(bit, addr) *addr ^= bit
60 * test_bit(bit, addr) Is bit set in *addr?
61 * test_and_set_bit(bit, addr) Set bit and return old value
62 * test_and_clear_bit(bit, addr) Clear bit and return old value
63 * test_and_change_bit(bit, addr) Change bit and return old value
64 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
65 * find_first_bit(addr, nbits) Position first set bit in *addr
66 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
67 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
68 */
69
70/*
71 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
72 * to declare an array named 'name' of just enough unsigned longs to
73 * contain all bit positions from 0 to 'bits' - 1.
74 */
75
76/*
77 * lib/bitmap.c provides these functions:
78 */
79
80extern int __bitmap_empty(const unsigned long *bitmap, int bits);
81extern int __bitmap_full(const unsigned long *bitmap, int bits);
82extern int __bitmap_equal(const unsigned long *bitmap1,
83 const unsigned long *bitmap2, int bits);
84extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
85 int bits);
86extern void __bitmap_shift_right(unsigned long *dst,
87 const unsigned long *src, int shift, int bits);
88extern void __bitmap_shift_left(unsigned long *dst,
89 const unsigned long *src, int shift, int bits);
90extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
91 const unsigned long *bitmap2, int bits);
92extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
93 const unsigned long *bitmap2, int bits);
94extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
95 const unsigned long *bitmap2, int bits);
96extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
97 const unsigned long *bitmap2, int bits);
98extern int __bitmap_intersects(const unsigned long *bitmap1,
99 const unsigned long *bitmap2, int bits);
100extern int __bitmap_subset(const unsigned long *bitmap1,
101 const unsigned long *bitmap2, int bits);
102extern int __bitmap_weight(const unsigned long *bitmap, int bits);
103
104extern int bitmap_scnprintf(char *buf, unsigned int len,
105 const unsigned long *src, int nbits);
106extern int bitmap_parse(const char __user *ubuf, unsigned int ulen,
107 unsigned long *dst, int nbits);
108extern int bitmap_scnlistprintf(char *buf, unsigned int len,
109 const unsigned long *src, int nbits);
110extern int bitmap_parselist(const char *buf, unsigned long *maskp,
111 int nmaskbits);
112extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
113 const unsigned long *old, const unsigned long *new, int bits);
114extern int bitmap_bitremap(int oldbit,
115 const unsigned long *old, const unsigned long *new, int bits);
116extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
117extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
118extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
119
120#define BITMAP_LAST_WORD_MASK(nbits) \
121( \
122 ((nbits) % BITS_PER_LONG) ? \
123 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
124)
125
126static inline void bitmap_zero(unsigned long *dst, int nbits)
127{
128 if (nbits <= BITS_PER_LONG)
129 *dst = 0UL;
130 else {
131 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
132 memset(dst, 0, len);
133 }
134}
135
136static inline void bitmap_fill(unsigned long *dst, int nbits)
137{
138 size_t nlongs = BITS_TO_LONGS(nbits);
139 if (nlongs > 1) {
140 int len = (nlongs - 1) * sizeof(unsigned long);
141 memset(dst, 0xff, len);
142 }
143 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
144}
145
146static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
147 int nbits)
148{
149 if (nbits <= BITS_PER_LONG)
150 *dst = *src;
151 else {
152 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
153 memcpy(dst, src, len);
154 }
155}
156
157static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
158 const unsigned long *src2, int nbits)
159{
160 if (nbits <= BITS_PER_LONG)
161 *dst = *src1 & *src2;
162 else
163 __bitmap_and(dst, src1, src2, nbits);
164}
165
166static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
167 const unsigned long *src2, int nbits)
168{
169 if (nbits <= BITS_PER_LONG)
170 *dst = *src1 | *src2;
171 else
172 __bitmap_or(dst, src1, src2, nbits);
173}
174
175static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
176 const unsigned long *src2, int nbits)
177{
178 if (nbits <= BITS_PER_LONG)
179 *dst = *src1 ^ *src2;
180 else
181 __bitmap_xor(dst, src1, src2, nbits);
182}
183
184static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
185 const unsigned long *src2, int nbits)
186{
187 if (nbits <= BITS_PER_LONG)
188 *dst = *src1 & ~(*src2);
189 else
190 __bitmap_andnot(dst, src1, src2, nbits);
191}
192
193static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
194 int nbits)
195{
196 if (nbits <= BITS_PER_LONG)
197 *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
198 else
199 __bitmap_complement(dst, src, nbits);
200}
201
202static inline int bitmap_equal(const unsigned long *src1,
203 const unsigned long *src2, int nbits)
204{
205 if (nbits <= BITS_PER_LONG)
206 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
207 else
208 return __bitmap_equal(src1, src2, nbits);
209}
210
211static inline int bitmap_intersects(const unsigned long *src1,
212 const unsigned long *src2, int nbits)
213{
214 if (nbits <= BITS_PER_LONG)
215 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
216 else
217 return __bitmap_intersects(src1, src2, nbits);
218}
219
220static inline int bitmap_subset(const unsigned long *src1,
221 const unsigned long *src2, int nbits)
222{
223 if (nbits <= BITS_PER_LONG)
224 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
225 else
226 return __bitmap_subset(src1, src2, nbits);
227}
228
229static inline int bitmap_empty(const unsigned long *src, int nbits)
230{
231 if (nbits <= BITS_PER_LONG)
232 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
233 else
234 return __bitmap_empty(src, nbits);
235}
236
237static inline int bitmap_full(const unsigned long *src, int nbits)
238{
239 if (nbits <= BITS_PER_LONG)
240 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
241 else
242 return __bitmap_full(src, nbits);
243}
244
245static inline int bitmap_weight(const unsigned long *src, int nbits)
246{
247 return __bitmap_weight(src, nbits);
248}
249
250static inline void bitmap_shift_right(unsigned long *dst,
251 const unsigned long *src, int n, int nbits)
252{
253 if (nbits <= BITS_PER_LONG)
254 *dst = *src >> n;
255 else
256 __bitmap_shift_right(dst, src, n, nbits);
257}
258
259static inline void bitmap_shift_left(unsigned long *dst,
260 const unsigned long *src, int n, int nbits)
261{
262 if (nbits <= BITS_PER_LONG)
263 *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
264 else
265 __bitmap_shift_left(dst, src, n, nbits);
266}
267
268#endif /* __ASSEMBLY__ */
269
270#endif /* __LINUX_BITMAP_H */