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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_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_shift_right(dst, src, n, nbits) *dst = *src >> n
49 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
50 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
51 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
52 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
53 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
54 * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
55 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
56 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
57 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
58 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
59 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
60 * bitmap_release_region(bitmap, pos, order) Free specified bit region
61 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
62 */
63
64/*
65 * Also the following operations in asm/bitops.h apply to bitmaps.
66 *
67 * set_bit(bit, addr) *addr |= bit
68 * clear_bit(bit, addr) *addr &= ~bit
69 * change_bit(bit, addr) *addr ^= bit
70 * test_bit(bit, addr) Is bit set in *addr?
71 * test_and_set_bit(bit, addr) Set bit and return old value
72 * test_and_clear_bit(bit, addr) Clear bit and return old value
73 * test_and_change_bit(bit, addr) Change bit and return old value
74 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
75 * find_first_bit(addr, nbits) Position first set bit in *addr
76 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
77 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
78 */
79
80/*
81 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
82 * to declare an array named 'name' of just enough unsigned longs to
83 * contain all bit positions from 0 to 'bits' - 1.
84 */
85
86/*
87 * lib/bitmap.c provides these functions:
88 */
89
90extern int __bitmap_empty(const unsigned long *bitmap, int bits);
91extern int __bitmap_full(const unsigned long *bitmap, int bits);
92extern int __bitmap_equal(const unsigned long *bitmap1,
93 const unsigned long *bitmap2, int bits);
94extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
95 int bits);
96extern void __bitmap_shift_right(unsigned long *dst,
97 const unsigned long *src, int shift, int bits);
98extern void __bitmap_shift_left(unsigned long *dst,
99 const unsigned long *src, int shift, int bits);
100extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
101 const unsigned long *bitmap2, int bits);
102extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
103 const unsigned long *bitmap2, int bits);
104extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
105 const unsigned long *bitmap2, int bits);
106extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
107 const unsigned long *bitmap2, int bits);
108extern int __bitmap_intersects(const unsigned long *bitmap1,
109 const unsigned long *bitmap2, int bits);
110extern int __bitmap_subset(const unsigned long *bitmap1,
111 const unsigned long *bitmap2, int bits);
112extern int __bitmap_weight(const unsigned long *bitmap, int bits);
113
114extern void bitmap_set(unsigned long *map, int i, int len);
115extern void bitmap_clear(unsigned long *map, int start, int nr);
116extern unsigned long bitmap_find_next_zero_area(unsigned long *map,
117 unsigned long size,
118 unsigned long start,
119 unsigned int nr,
120 unsigned long align_mask);
121
122extern int bitmap_scnprintf(char *buf, unsigned int len,
123 const unsigned long *src, int nbits);
124extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
125 unsigned long *dst, int nbits);
126extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
127 unsigned long *dst, int nbits);
128extern int bitmap_scnlistprintf(char *buf, unsigned int len,
129 const unsigned long *src, int nbits);
130extern int bitmap_parselist(const char *buf, unsigned long *maskp,
131 int nmaskbits);
132extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
133 const unsigned long *old, const unsigned long *new, int bits);
134extern int bitmap_bitremap(int oldbit,
135 const unsigned long *old, const unsigned long *new, int bits);
136extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
137 const unsigned long *relmap, int bits);
138extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
139 int sz, int bits);
140extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
141extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
142extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
143extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits);
144
145#define BITMAP_LAST_WORD_MASK(nbits) \
146( \
147 ((nbits) % BITS_PER_LONG) ? \
148 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
149)
150
151#define small_const_nbits(nbits) \
152 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
153
154static inline void bitmap_zero(unsigned long *dst, int nbits)
155{
156 if (small_const_nbits(nbits))
157 *dst = 0UL;
158 else {
159 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
160 memset(dst, 0, len);
161 }
162}
163
164static inline void bitmap_fill(unsigned long *dst, int nbits)
165{
166 size_t nlongs = BITS_TO_LONGS(nbits);
167 if (!small_const_nbits(nbits)) {
168 int len = (nlongs - 1) * sizeof(unsigned long);
169 memset(dst, 0xff, len);
170 }
171 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
172}
173
174static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
175 int nbits)
176{
177 if (small_const_nbits(nbits))
178 *dst = *src;
179 else {
180 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
181 memcpy(dst, src, len);
182 }
183}
184
185static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
186 const unsigned long *src2, int nbits)
187{
188 if (small_const_nbits(nbits))
189 return (*dst = *src1 & *src2) != 0;
190 return __bitmap_and(dst, src1, src2, nbits);
191}
192
193static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
194 const unsigned long *src2, int nbits)
195{
196 if (small_const_nbits(nbits))
197 *dst = *src1 | *src2;
198 else
199 __bitmap_or(dst, src1, src2, nbits);
200}
201
202static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
203 const unsigned long *src2, int nbits)
204{
205 if (small_const_nbits(nbits))
206 *dst = *src1 ^ *src2;
207 else
208 __bitmap_xor(dst, src1, src2, nbits);
209}
210
211static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
212 const unsigned long *src2, int nbits)
213{
214 if (small_const_nbits(nbits))
215 return (*dst = *src1 & ~(*src2)) != 0;
216 return __bitmap_andnot(dst, src1, src2, nbits);
217}
218
219static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
220 int nbits)
221{
222 if (small_const_nbits(nbits))
223 *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
224 else
225 __bitmap_complement(dst, src, nbits);
226}
227
228static inline int bitmap_equal(const unsigned long *src1,
229 const unsigned long *src2, int nbits)
230{
231 if (small_const_nbits(nbits))
232 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
233 else
234 return __bitmap_equal(src1, src2, nbits);
235}
236
237static inline int bitmap_intersects(const unsigned long *src1,
238 const unsigned long *src2, int nbits)
239{
240 if (small_const_nbits(nbits))
241 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
242 else
243 return __bitmap_intersects(src1, src2, nbits);
244}
245
246static inline int bitmap_subset(const unsigned long *src1,
247 const unsigned long *src2, int nbits)
248{
249 if (small_const_nbits(nbits))
250 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
251 else
252 return __bitmap_subset(src1, src2, nbits);
253}
254
255static inline int bitmap_empty(const unsigned long *src, int nbits)
256{
257 if (small_const_nbits(nbits))
258 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
259 else
260 return __bitmap_empty(src, nbits);
261}
262
263static inline int bitmap_full(const unsigned long *src, int nbits)
264{
265 if (small_const_nbits(nbits))
266 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
267 else
268 return __bitmap_full(src, nbits);
269}
270
271static inline int bitmap_weight(const unsigned long *src, int nbits)
272{
273 if (small_const_nbits(nbits))
274 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
275 return __bitmap_weight(src, nbits);
276}
277
278static inline void bitmap_shift_right(unsigned long *dst,
279 const unsigned long *src, int n, int nbits)
280{
281 if (small_const_nbits(nbits))
282 *dst = *src >> n;
283 else
284 __bitmap_shift_right(dst, src, n, nbits);
285}
286
287static inline void bitmap_shift_left(unsigned long *dst,
288 const unsigned long *src, int n, int nbits)
289{
290 if (small_const_nbits(nbits))
291 *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
292 else
293 __bitmap_shift_left(dst, src, n, nbits);
294}
295
296static inline int bitmap_parse(const char *buf, unsigned int buflen,
297 unsigned long *maskp, int nmaskbits)
298{
299 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
300}
301
302#endif /* __ASSEMBLY__ */
303
304#endif /* __LINUX_BITMAP_H */