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