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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 * bitmap_from_u32array(dst, nbits, buf, nwords) *dst = *buf (nwords 32b words)
63 * bitmap_to_u32array(buf, nwords, src, nbits) *buf = *dst (nwords 32b words)
64 */
65
66/*
67 * Also the following operations in asm/bitops.h apply to bitmaps.
68 *
69 * set_bit(bit, addr) *addr |= bit
70 * clear_bit(bit, addr) *addr &= ~bit
71 * change_bit(bit, addr) *addr ^= bit
72 * test_bit(bit, addr) Is bit set in *addr?
73 * test_and_set_bit(bit, addr) Set bit and return old value
74 * test_and_clear_bit(bit, addr) Clear bit and return old value
75 * test_and_change_bit(bit, addr) Change bit and return old value
76 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
77 * find_first_bit(addr, nbits) Position first set bit in *addr
78 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
79 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
80 */
81
82/*
83 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
84 * to declare an array named 'name' of just enough unsigned longs to
85 * contain all bit positions from 0 to 'bits' - 1.
86 */
87
88/*
89 * lib/bitmap.c provides these functions:
90 */
91
92extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
93extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
94extern int __bitmap_equal(const unsigned long *bitmap1,
95 const unsigned long *bitmap2, unsigned int nbits);
96extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
97 unsigned int nbits);
98extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
99 unsigned int shift, unsigned int nbits);
100extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
101 unsigned int shift, unsigned int nbits);
102extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
103 const unsigned long *bitmap2, unsigned int nbits);
104extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
105 const unsigned long *bitmap2, unsigned int nbits);
106extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
107 const unsigned long *bitmap2, unsigned int nbits);
108extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
109 const unsigned long *bitmap2, unsigned int nbits);
110extern int __bitmap_intersects(const unsigned long *bitmap1,
111 const unsigned long *bitmap2, unsigned int nbits);
112extern int __bitmap_subset(const unsigned long *bitmap1,
113 const unsigned long *bitmap2, unsigned int nbits);
114extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
115
116extern void bitmap_set(unsigned long *map, unsigned int start, int len);
117extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
118
119extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
120 unsigned long size,
121 unsigned long start,
122 unsigned int nr,
123 unsigned long align_mask,
124 unsigned long align_offset);
125
126/**
127 * bitmap_find_next_zero_area - find a contiguous aligned zero area
128 * @map: The address to base the search on
129 * @size: The bitmap size in bits
130 * @start: The bitnumber to start searching at
131 * @nr: The number of zeroed bits we're looking for
132 * @align_mask: Alignment mask for zero area
133 *
134 * The @align_mask should be one less than a power of 2; the effect is that
135 * the bit offset of all zero areas this function finds is multiples of that
136 * power of 2. A @align_mask of 0 means no alignment is required.
137 */
138static inline unsigned long
139bitmap_find_next_zero_area(unsigned long *map,
140 unsigned long size,
141 unsigned long start,
142 unsigned int nr,
143 unsigned long align_mask)
144{
145 return bitmap_find_next_zero_area_off(map, size, start, nr,
146 align_mask, 0);
147}
148
149extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
150 unsigned long *dst, int nbits);
151extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
152 unsigned long *dst, int nbits);
153extern int bitmap_parselist(const char *buf, unsigned long *maskp,
154 int nmaskbits);
155extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
156 unsigned long *dst, int nbits);
157extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
158 const unsigned long *old, const unsigned long *new, unsigned int nbits);
159extern int bitmap_bitremap(int oldbit,
160 const unsigned long *old, const unsigned long *new, int bits);
161extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
162 const unsigned long *relmap, unsigned int bits);
163extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
164 unsigned int sz, unsigned int nbits);
165extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
166extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
167extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
168extern unsigned int bitmap_from_u32array(unsigned long *bitmap,
169 unsigned int nbits,
170 const u32 *buf,
171 unsigned int nwords);
172extern unsigned int bitmap_to_u32array(u32 *buf,
173 unsigned int nwords,
174 const unsigned long *bitmap,
175 unsigned int nbits);
176#ifdef __BIG_ENDIAN
177extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
178#else
179#define bitmap_copy_le bitmap_copy
180#endif
181extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
182extern int bitmap_print_to_pagebuf(bool list, char *buf,
183 const unsigned long *maskp, int nmaskbits);
184
185#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
186#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
187
188#define small_const_nbits(nbits) \
189 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
190
191static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
192{
193 if (small_const_nbits(nbits))
194 *dst = 0UL;
195 else {
196 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
197 memset(dst, 0, len);
198 }
199}
200
201static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
202{
203 unsigned int nlongs = BITS_TO_LONGS(nbits);
204 if (!small_const_nbits(nbits)) {
205 unsigned int len = (nlongs - 1) * sizeof(unsigned long);
206 memset(dst, 0xff, len);
207 }
208 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
209}
210
211static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
212 unsigned int nbits)
213{
214 if (small_const_nbits(nbits))
215 *dst = *src;
216 else {
217 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
218 memcpy(dst, src, len);
219 }
220}
221
222static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
223 const unsigned long *src2, unsigned int nbits)
224{
225 if (small_const_nbits(nbits))
226 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
227 return __bitmap_and(dst, src1, src2, nbits);
228}
229
230static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
231 const unsigned long *src2, unsigned int nbits)
232{
233 if (small_const_nbits(nbits))
234 *dst = *src1 | *src2;
235 else
236 __bitmap_or(dst, src1, src2, nbits);
237}
238
239static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
240 const unsigned long *src2, unsigned int nbits)
241{
242 if (small_const_nbits(nbits))
243 *dst = *src1 ^ *src2;
244 else
245 __bitmap_xor(dst, src1, src2, nbits);
246}
247
248static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
249 const unsigned long *src2, unsigned int nbits)
250{
251 if (small_const_nbits(nbits))
252 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
253 return __bitmap_andnot(dst, src1, src2, nbits);
254}
255
256static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
257 unsigned int nbits)
258{
259 if (small_const_nbits(nbits))
260 *dst = ~(*src);
261 else
262 __bitmap_complement(dst, src, nbits);
263}
264
265static inline int bitmap_equal(const unsigned long *src1,
266 const unsigned long *src2, unsigned int nbits)
267{
268 if (small_const_nbits(nbits))
269 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
270 else
271 return __bitmap_equal(src1, src2, nbits);
272}
273
274static inline int bitmap_intersects(const unsigned long *src1,
275 const unsigned long *src2, unsigned int nbits)
276{
277 if (small_const_nbits(nbits))
278 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
279 else
280 return __bitmap_intersects(src1, src2, nbits);
281}
282
283static inline int bitmap_subset(const unsigned long *src1,
284 const unsigned long *src2, unsigned int nbits)
285{
286 if (small_const_nbits(nbits))
287 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
288 else
289 return __bitmap_subset(src1, src2, nbits);
290}
291
292static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
293{
294 if (small_const_nbits(nbits))
295 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
296
297 return find_first_bit(src, nbits) == nbits;
298}
299
300static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
301{
302 if (small_const_nbits(nbits))
303 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
304
305 return find_first_zero_bit(src, nbits) == nbits;
306}
307
308static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
309{
310 if (small_const_nbits(nbits))
311 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
312 return __bitmap_weight(src, nbits);
313}
314
315static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
316 unsigned int shift, int nbits)
317{
318 if (small_const_nbits(nbits))
319 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
320 else
321 __bitmap_shift_right(dst, src, shift, nbits);
322}
323
324static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
325 unsigned int shift, unsigned int nbits)
326{
327 if (small_const_nbits(nbits))
328 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
329 else
330 __bitmap_shift_left(dst, src, shift, nbits);
331}
332
333static inline int bitmap_parse(const char *buf, unsigned int buflen,
334 unsigned long *maskp, int nmaskbits)
335{
336 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
337}
338
339#endif /* __ASSEMBLY__ */
340
341#endif /* __LINUX_BITMAP_H */