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