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
92 extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
93 extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
94 extern int __bitmap_equal(const unsigned long *bitmap1,
95 const unsigned long *bitmap2, unsigned int nbits);
96 extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
97 unsigned int nbits);
98 extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
99 unsigned int shift, unsigned int nbits);
100 extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
101 unsigned int shift, unsigned int nbits);
102 extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
103 const unsigned long *bitmap2, unsigned int nbits);
104 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
105 const unsigned long *bitmap2, unsigned int nbits);
106 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
107 const unsigned long *bitmap2, unsigned int nbits);
108 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
109 const unsigned long *bitmap2, unsigned int nbits);
110 extern int __bitmap_intersects(const unsigned long *bitmap1,
111 const unsigned long *bitmap2, unsigned int nbits);
112 extern int __bitmap_subset(const unsigned long *bitmap1,
113 const unsigned long *bitmap2, unsigned int nbits);
114 extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
115
116 extern void bitmap_set(unsigned long *map, unsigned int start, int len);
117 extern void bitmap_clear(unsigned long *map, unsigned int start, int len);
118
119 extern 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 */
138 static inline unsigned long
bitmap_find_next_zero_area(unsigned long * map,unsigned long size,unsigned long start,unsigned int nr,unsigned long align_mask)139 bitmap_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
149 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
150 unsigned long *dst, int nbits);
151 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
152 unsigned long *dst, int nbits);
153 extern int bitmap_parselist(const char *buf, unsigned long *maskp,
154 int nmaskbits);
155 extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
156 unsigned long *dst, int nbits);
157 extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
158 const unsigned long *old, const unsigned long *new, unsigned int nbits);
159 extern int bitmap_bitremap(int oldbit,
160 const unsigned long *old, const unsigned long *new, int bits);
161 extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
162 const unsigned long *relmap, unsigned int bits);
163 extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
164 unsigned int sz, unsigned int nbits);
165 extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
166 extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
167 extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
168 extern unsigned int bitmap_from_u32array(unsigned long *bitmap,
169 unsigned int nbits,
170 const u32 *buf,
171 unsigned int nwords);
172 extern unsigned int bitmap_to_u32array(u32 *buf,
173 unsigned int nwords,
174 const unsigned long *bitmap,
175 unsigned int nbits);
176 #ifdef __BIG_ENDIAN
177 extern 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
181 extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
182 extern 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
bitmap_zero(unsigned long * dst,unsigned int nbits)191 static 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
bitmap_fill(unsigned long * dst,unsigned int nbits)201 static 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
bitmap_copy(unsigned long * dst,const unsigned long * src,unsigned int nbits)211 static 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
bitmap_and(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)222 static 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
bitmap_or(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)230 static 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
bitmap_xor(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)239 static 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
bitmap_andnot(unsigned long * dst,const unsigned long * src1,const unsigned long * src2,unsigned int nbits)248 static 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
bitmap_complement(unsigned long * dst,const unsigned long * src,unsigned int nbits)256 static 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
bitmap_equal(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)265 static 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 #ifdef CONFIG_S390
271 if (__builtin_constant_p(nbits) && (nbits % BITS_PER_LONG) == 0)
272 return !memcmp(src1, src2, nbits / 8);
273 #endif
274 return __bitmap_equal(src1, src2, nbits);
275 }
276
bitmap_intersects(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)277 static inline int bitmap_intersects(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)) != 0;
282 else
283 return __bitmap_intersects(src1, src2, nbits);
284 }
285
bitmap_subset(const unsigned long * src1,const unsigned long * src2,unsigned int nbits)286 static inline int bitmap_subset(const unsigned long *src1,
287 const unsigned long *src2, unsigned int nbits)
288 {
289 if (small_const_nbits(nbits))
290 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
291 else
292 return __bitmap_subset(src1, src2, nbits);
293 }
294
bitmap_empty(const unsigned long * src,unsigned nbits)295 static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
296 {
297 if (small_const_nbits(nbits))
298 return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
299
300 return find_first_bit(src, nbits) == nbits;
301 }
302
bitmap_full(const unsigned long * src,unsigned int nbits)303 static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
304 {
305 if (small_const_nbits(nbits))
306 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
307
308 return find_first_zero_bit(src, nbits) == nbits;
309 }
310
bitmap_weight(const unsigned long * src,unsigned int nbits)311 static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
312 {
313 if (small_const_nbits(nbits))
314 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
315 return __bitmap_weight(src, nbits);
316 }
317
bitmap_shift_right(unsigned long * dst,const unsigned long * src,unsigned int shift,int nbits)318 static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
319 unsigned int shift, int nbits)
320 {
321 if (small_const_nbits(nbits))
322 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
323 else
324 __bitmap_shift_right(dst, src, shift, nbits);
325 }
326
bitmap_shift_left(unsigned long * dst,const unsigned long * src,unsigned int shift,unsigned int nbits)327 static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
328 unsigned int shift, unsigned int nbits)
329 {
330 if (small_const_nbits(nbits))
331 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
332 else
333 __bitmap_shift_left(dst, src, shift, nbits);
334 }
335
bitmap_parse(const char * buf,unsigned int buflen,unsigned long * maskp,int nmaskbits)336 static inline int bitmap_parse(const char *buf, unsigned int buflen,
337 unsigned long *maskp, int nmaskbits)
338 {
339 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
340 }
341
342 /*
343 * bitmap_from_u64 - Check and swap words within u64.
344 * @mask: source bitmap
345 * @dst: destination bitmap
346 *
347 * In 32-bit Big Endian kernel, when using (u32 *)(&val)[*]
348 * to read u64 mask, we will get the wrong word.
349 * That is "(u32 *)(&val)[0]" gets the upper 32 bits,
350 * but we expect the lower 32-bits of u64.
351 */
bitmap_from_u64(unsigned long * dst,u64 mask)352 static inline void bitmap_from_u64(unsigned long *dst, u64 mask)
353 {
354 dst[0] = mask & ULONG_MAX;
355
356 if (sizeof(mask) > sizeof(unsigned long))
357 dst[1] = mask >> 32;
358 }
359
360 #endif /* __ASSEMBLY__ */
361
362 #endif /* __LINUX_BITMAP_H */
363