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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_find_next_zero_area_off(buf, len, pos, n, mask) as above
49 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
50 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
51 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
52 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
53 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
54 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
55 * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
56 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
57 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
58 * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
59 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
60 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
61 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
62 * bitmap_release_region(bitmap, pos, order) Free specified bit region
63 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
64 * bitmap_print_to_pagebuf(list, buf, mask, nbits) Print bitmap src as list/hex
65 */
66
67/*
68 * Also the following operations in asm/bitops.h apply to bitmaps.
69 *
70 * set_bit(bit, addr) *addr |= bit
71 * clear_bit(bit, addr) *addr &= ~bit
72 * change_bit(bit, addr) *addr ^= bit
73 * test_bit(bit, addr) Is bit set in *addr?
74 * test_and_set_bit(bit, addr) Set bit and return old value
75 * test_and_clear_bit(bit, addr) Clear bit and return old value
76 * test_and_change_bit(bit, addr) Change bit and return old value
77 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
78 * find_first_bit(addr, nbits) Position first set bit in *addr
79 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
80 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
81 */
82
83/*
84 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
85 * to declare an array named 'name' of just enough unsigned longs to
86 * contain all bit positions from 0 to 'bits' - 1.
87 */
88
89/*
90 * lib/bitmap.c provides these functions:
91 */
92
93extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
94extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
95extern int __bitmap_equal(const unsigned long *bitmap1,
96 const unsigned long *bitmap2, unsigned int nbits);
97extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
98 unsigned int nbits);
99extern void __bitmap_shift_right(unsigned long *dst,
100 const unsigned long *src, int shift, int bits);
101extern void __bitmap_shift_left(unsigned long *dst,
102 const unsigned long *src, int shift, int bits);
103extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
104 const unsigned long *bitmap2, unsigned int nbits);
105extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
106 const unsigned long *bitmap2, unsigned int nbits);
107extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
108 const unsigned long *bitmap2, unsigned int nbits);
109extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
110 const unsigned long *bitmap2, unsigned int nbits);
111extern int __bitmap_intersects(const unsigned long *bitmap1,
112 const unsigned long *bitmap2, unsigned int nbits);
113extern int __bitmap_subset(const unsigned long *bitmap1,
114 const unsigned long *bitmap2, unsigned int nbits);
115extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
116
117extern void bitmap_set(unsigned long *map, unsigned int start, int len);
118extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
119
120extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
121 unsigned long size,
122 unsigned long start,
123 unsigned int nr,
124 unsigned long align_mask,
125 unsigned long align_offset);
126
127/**
128 * bitmap_find_next_zero_area - find a contiguous aligned zero area
129 * @map: The address to base the search on
130 * @size: The bitmap size in bits
131 * @start: The bitnumber to start searching at
132 * @nr: The number of zeroed bits we're looking for
133 * @align_mask: Alignment mask for zero area
134 *
135 * The @align_mask should be one less than a power of 2; the effect is that
136 * the bit offset of all zero areas this function finds is multiples of that
137 * power of 2. A @align_mask of 0 means no alignment is required.
138 */
139static inline unsigned long
140bitmap_find_next_zero_area(unsigned long *map,
141 unsigned long size,
142 unsigned long start,
143 unsigned int nr,
144 unsigned long align_mask)
145{
146 return bitmap_find_next_zero_area_off(map, size, start, nr,
147 align_mask, 0);
148}
149
150extern int bitmap_scnprintf(char *buf, unsigned int len,
151 const unsigned long *src, int nbits);
152extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
153 unsigned long *dst, int nbits);
154extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
155 unsigned long *dst, int nbits);
156extern int bitmap_scnlistprintf(char *buf, unsigned int len,
157 const unsigned long *src, int nbits);
158extern int bitmap_parselist(const char *buf, unsigned long *maskp,
159 int nmaskbits);
160extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
161 unsigned long *dst, int nbits);
162extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
163 const unsigned long *old, const unsigned long *new, int bits);
164extern int bitmap_bitremap(int oldbit,
165 const unsigned long *old, const unsigned long *new, int bits);
166extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
167 const unsigned long *relmap, int bits);
168extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
169 int sz, int bits);
170extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
171extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
172extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
173extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits);
174extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits);
175extern int bitmap_print_to_pagebuf(bool list, char *buf,
176 const unsigned long *maskp, int nmaskbits);
177
178#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))
179#define BITMAP_LAST_WORD_MASK(nbits) \
180( \
181 ((nbits) % BITS_PER_LONG) ? \
182 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
183)
184
185#define small_const_nbits(nbits) \
186 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
187
188static inline void bitmap_zero(unsigned long *dst, int nbits)
189{
190 if (small_const_nbits(nbits))
191 *dst = 0UL;
192 else {
193 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
194 memset(dst, 0, len);
195 }
196}
197
198static inline void bitmap_fill(unsigned long *dst, int nbits)
199{
200 size_t nlongs = BITS_TO_LONGS(nbits);
201 if (!small_const_nbits(nbits)) {
202 int len = (nlongs - 1) * sizeof(unsigned long);
203 memset(dst, 0xff, len);
204 }
205 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
206}
207
208static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
209 int nbits)
210{
211 if (small_const_nbits(nbits))
212 *dst = *src;
213 else {
214 int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
215 memcpy(dst, src, len);
216 }
217}
218
219static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
220 const unsigned long *src2, unsigned int nbits)
221{
222 if (small_const_nbits(nbits))
223 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
224 return __bitmap_and(dst, src1, src2, nbits);
225}
226
227static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
228 const unsigned long *src2, unsigned int nbits)
229{
230 if (small_const_nbits(nbits))
231 *dst = *src1 | *src2;
232 else
233 __bitmap_or(dst, src1, src2, nbits);
234}
235
236static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
237 const unsigned long *src2, unsigned int nbits)
238{
239 if (small_const_nbits(nbits))
240 *dst = *src1 ^ *src2;
241 else
242 __bitmap_xor(dst, src1, src2, nbits);
243}
244
245static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
246 const unsigned long *src2, unsigned int nbits)
247{
248 if (small_const_nbits(nbits))
249 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
250 return __bitmap_andnot(dst, src1, src2, nbits);
251}
252
253static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
254 unsigned int nbits)
255{
256 if (small_const_nbits(nbits))
257 *dst = ~(*src);
258 else
259 __bitmap_complement(dst, src, nbits);
260}
261
262static inline int bitmap_equal(const unsigned long *src1,
263 const unsigned long *src2, unsigned int nbits)
264{
265 if (small_const_nbits(nbits))
266 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
267 else
268 return __bitmap_equal(src1, src2, nbits);
269}
270
271static inline int bitmap_intersects(const unsigned long *src1,
272 const unsigned long *src2, unsigned int nbits)
273{
274 if (small_const_nbits(nbits))
275 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
276 else
277 return __bitmap_intersects(src1, src2, nbits);
278}
279
280static inline int bitmap_subset(const unsigned long *src1,
281 const unsigned long *src2, unsigned int nbits)
282{
283 if (small_const_nbits(nbits))
284 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
285 else
286 return __bitmap_subset(src1, src2, nbits);
287}
288
289static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
290{
291 if (small_const_nbits(nbits))
292 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
293 else
294 return __bitmap_empty(src, nbits);
295}
296
297static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
298{
299 if (small_const_nbits(nbits))
300 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
301 else
302 return __bitmap_full(src, nbits);
303}
304
305static inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
306{
307 if (small_const_nbits(nbits))
308 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
309 return __bitmap_weight(src, nbits);
310}
311
312static inline void bitmap_shift_right(unsigned long *dst,
313 const unsigned long *src, int n, int nbits)
314{
315 if (small_const_nbits(nbits))
316 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> n;
317 else
318 __bitmap_shift_right(dst, src, n, nbits);
319}
320
321static inline void bitmap_shift_left(unsigned long *dst,
322 const unsigned long *src, int n, int nbits)
323{
324 if (small_const_nbits(nbits))
325 *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
326 else
327 __bitmap_shift_left(dst, src, n, nbits);
328}
329
330static inline int bitmap_parse(const char *buf, unsigned int buflen,
331 unsigned long *maskp, int nmaskbits)
332{
333 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
334}
335
336#endif /* __ASSEMBLY__ */
337
338#endif /* __LINUX_BITMAP_H */