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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_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_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
58 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
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, unsigned int nbits);
91extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
92extern int __bitmap_equal(const unsigned long *bitmap1,
93 const unsigned long *bitmap2, unsigned int nbits);
94extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
95 unsigned int nbits);
96extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
97 unsigned int shift, unsigned int nbits);
98extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
99 unsigned int shift, unsigned int nbits);
100extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
101 const unsigned long *bitmap2, unsigned int nbits);
102extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
103 const unsigned long *bitmap2, unsigned int nbits);
104extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
105 const unsigned long *bitmap2, unsigned int nbits);
106extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
107 const unsigned long *bitmap2, unsigned int nbits);
108extern int __bitmap_intersects(const unsigned long *bitmap1,
109 const unsigned long *bitmap2, unsigned int nbits);
110extern int __bitmap_subset(const unsigned long *bitmap1,
111 const unsigned long *bitmap2, unsigned int nbits);
112extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
113
114extern void bitmap_set(unsigned long *map, unsigned int start, int len);
115extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
116
117extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
118 unsigned long size,
119 unsigned long start,
120 unsigned int nr,
121 unsigned long align_mask,
122 unsigned long align_offset);
123
124/**
125 * bitmap_find_next_zero_area - find a contiguous aligned zero area
126 * @map: The address to base the search on
127 * @size: The bitmap size in bits
128 * @start: The bitnumber to start searching at
129 * @nr: The number of zeroed bits we're looking for
130 * @align_mask: Alignment mask for zero area
131 *
132 * The @align_mask should be one less than a power of 2; the effect is that
133 * the bit offset of all zero areas this function finds is multiples of that
134 * power of 2. A @align_mask of 0 means no alignment is required.
135 */
136static inline unsigned long
137bitmap_find_next_zero_area(unsigned long *map,
138 unsigned long size,
139 unsigned long start,
140 unsigned int nr,
141 unsigned long align_mask)
142{
143 return bitmap_find_next_zero_area_off(map, size, start, nr,
144 align_mask, 0);
145}
146
147extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
148 unsigned long *dst, int nbits);
149extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
150 unsigned long *dst, int nbits);
151extern int bitmap_parselist(const char *buf, unsigned long *maskp,
152 int nmaskbits);
153extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
154 unsigned long *dst, int nbits);
155extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
156 const unsigned long *old, const unsigned long *new, unsigned int nbits);
157extern int bitmap_bitremap(int oldbit,
158 const unsigned long *old, const unsigned long *new, int bits);
159extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
160 const unsigned long *relmap, unsigned int bits);
161extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
162 unsigned int sz, unsigned int nbits);
163extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
164extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
165extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
166#ifdef __BIG_ENDIAN
167extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
168#else
169#define bitmap_copy_le bitmap_copy
170#endif
171extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
172extern int bitmap_print_to_pagebuf(bool list, char *buf,
173 const unsigned long *maskp, int nmaskbits);
174
175#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))
176#define BITMAP_LAST_WORD_MASK(nbits) \
177( \
178 ((nbits) % BITS_PER_LONG) ? \
179 (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
180)
181
182#define small_const_nbits(nbits) \
183 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
184
185static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
186{
187 if (small_const_nbits(nbits))
188 *dst = 0UL;
189 else {
190 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
191 memset(dst, 0, len);
192 }
193}
194
195static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
196{
197 unsigned int nlongs = BITS_TO_LONGS(nbits);
198 if (!small_const_nbits(nbits)) {
199 unsigned int len = (nlongs - 1) * sizeof(unsigned long);
200 memset(dst, 0xff, len);
201 }
202 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
203}
204
205static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
206 unsigned int nbits)
207{
208 if (small_const_nbits(nbits))
209 *dst = *src;
210 else {
211 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
212 memcpy(dst, src, len);
213 }
214}
215
216static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
217 const unsigned long *src2, unsigned int nbits)
218{
219 if (small_const_nbits(nbits))
220 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
221 return __bitmap_and(dst, src1, src2, nbits);
222}
223
224static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
225 const unsigned long *src2, unsigned int nbits)
226{
227 if (small_const_nbits(nbits))
228 *dst = *src1 | *src2;
229 else
230 __bitmap_or(dst, src1, src2, nbits);
231}
232
233static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
234 const unsigned long *src2, unsigned int nbits)
235{
236 if (small_const_nbits(nbits))
237 *dst = *src1 ^ *src2;
238 else
239 __bitmap_xor(dst, src1, src2, nbits);
240}
241
242static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
243 const unsigned long *src2, unsigned int nbits)
244{
245 if (small_const_nbits(nbits))
246 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
247 return __bitmap_andnot(dst, src1, src2, nbits);
248}
249
250static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
251 unsigned int nbits)
252{
253 if (small_const_nbits(nbits))
254 *dst = ~(*src);
255 else
256 __bitmap_complement(dst, src, nbits);
257}
258
259static inline int bitmap_equal(const unsigned long *src1,
260 const unsigned long *src2, unsigned int nbits)
261{
262 if (small_const_nbits(nbits))
263 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
264 else
265 return __bitmap_equal(src1, src2, nbits);
266}
267
268static inline int bitmap_intersects(const unsigned long *src1,
269 const unsigned long *src2, unsigned int nbits)
270{
271 if (small_const_nbits(nbits))
272 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
273 else
274 return __bitmap_intersects(src1, src2, nbits);
275}
276
277static inline int bitmap_subset(const unsigned long *src1,
278 const unsigned long *src2, unsigned int nbits)
279{
280 if (small_const_nbits(nbits))
281 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
282 else
283 return __bitmap_subset(src1, src2, nbits);
284}
285
286static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
287{
288 if (small_const_nbits(nbits))
289 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
290 else
291 return __bitmap_empty(src, nbits);
292}
293
294static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
295{
296 if (small_const_nbits(nbits))
297 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
298 else
299 return __bitmap_full(src, nbits);
300}
301
302static inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
303{
304 if (small_const_nbits(nbits))
305 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
306 return __bitmap_weight(src, nbits);
307}
308
309static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
310 unsigned int shift, int nbits)
311{
312 if (small_const_nbits(nbits))
313 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
314 else
315 __bitmap_shift_right(dst, src, shift, nbits);
316}
317
318static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
319 unsigned int shift, unsigned int nbits)
320{
321 if (small_const_nbits(nbits))
322 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
323 else
324 __bitmap_shift_left(dst, src, shift, nbits);
325}
326
327static inline int bitmap_parse(const char *buf, unsigned int buflen,
328 unsigned long *maskp, int nmaskbits)
329{
330 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
331}
332
333#endif /* __ASSEMBLY__ */
334
335#endif /* __LINUX_BITMAP_H */