Commit | Line | Data |
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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | #ifndef __LINUX_BITMAP_H |
3 | #define __LINUX_BITMAP_H | |
4 | ||
5 | #ifndef __ASSEMBLY__ | |
6 | ||
7 | #include <linux/types.h> | |
8 | #include <linux/bitops.h> | |
9 | #include <linux/string.h> | |
14ed9d23 | 10 | #include <linux/kernel.h> |
1da177e4 LT |
11 | |
12 | /* | |
13 | * bitmaps provide bit arrays that consume one or more unsigned | |
14 | * longs. The bitmap interface and available operations are listed | |
15 | * here, in bitmap.h | |
16 | * | |
17 | * Function implementations generic to all architectures are in | |
18 | * lib/bitmap.c. Functions implementations that are architecture | |
19 | * specific are in various include/asm-<arch>/bitops.h headers | |
20 | * and other arch/<arch> specific files. | |
21 | * | |
22 | * See lib/bitmap.c for more details. | |
23 | */ | |
24 | ||
7d7363e4 RD |
25 | /** |
26 | * DOC: bitmap overview | |
27 | * | |
1da177e4 LT |
28 | * The available bitmap operations and their rough meaning in the |
29 | * case that the bitmap is a single unsigned long are thus: | |
30 | * | |
41e7b166 RV |
31 | * The generated code is more efficient when nbits is known at |
32 | * compile-time and at most BITS_PER_LONG. | |
08cd3657 | 33 | * |
7d7363e4 RD |
34 | * :: |
35 | * | |
36 | * bitmap_zero(dst, nbits) *dst = 0UL | |
37 | * bitmap_fill(dst, nbits) *dst = ~0UL | |
38 | * bitmap_copy(dst, src, nbits) *dst = *src | |
39 | * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 | |
40 | * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 | |
41 | * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 | |
42 | * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) | |
43 | * bitmap_complement(dst, src, nbits) *dst = ~(*src) | |
44 | * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal? | |
45 | * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap? | |
46 | * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2? | |
47 | * bitmap_empty(src, nbits) Are all bits zero in *src? | |
48 | * bitmap_full(src, nbits) Are all bits set in *src? | |
49 | * bitmap_weight(src, nbits) Hamming Weight: number set bits | |
50 | * bitmap_set(dst, pos, nbits) Set specified bit area | |
51 | * bitmap_clear(dst, pos, nbits) Clear specified bit area | |
52 | * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area | |
53 | * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above | |
54 | * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n | |
55 | * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n | |
56 | * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src) | |
57 | * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit) | |
58 | * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap | |
59 | * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz | |
60 | * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf | |
61 | * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf | |
62 | * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf | |
63 | * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf | |
64 | * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region | |
65 | * bitmap_release_region(bitmap, pos, order) Free specified bit region | |
66 | * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region | |
c724f193 YN |
67 | * bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst |
68 | * bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst | |
7d7363e4 | 69 | * |
334cfa48 AS |
70 | * Note, bitmap_zero() and bitmap_fill() operate over the region of |
71 | * unsigned longs, that is, bits behind bitmap till the unsigned long | |
72 | * boundary will be zeroed or filled as well. Consider to use | |
73 | * bitmap_clear() or bitmap_set() to make explicit zeroing or filling | |
74 | * respectively. | |
1da177e4 LT |
75 | */ |
76 | ||
7d7363e4 RD |
77 | /** |
78 | * DOC: bitmap bitops | |
79 | * | |
80 | * Also the following operations in asm/bitops.h apply to bitmaps.:: | |
81 | * | |
82 | * set_bit(bit, addr) *addr |= bit | |
83 | * clear_bit(bit, addr) *addr &= ~bit | |
84 | * change_bit(bit, addr) *addr ^= bit | |
85 | * test_bit(bit, addr) Is bit set in *addr? | |
86 | * test_and_set_bit(bit, addr) Set bit and return old value | |
87 | * test_and_clear_bit(bit, addr) Clear bit and return old value | |
88 | * test_and_change_bit(bit, addr) Change bit and return old value | |
89 | * find_first_zero_bit(addr, nbits) Position first zero bit in *addr | |
90 | * find_first_bit(addr, nbits) Position first set bit in *addr | |
0ade34c3 CC |
91 | * find_next_zero_bit(addr, nbits, bit) |
92 | * Position next zero bit in *addr >= bit | |
7d7363e4 | 93 | * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit |
0ade34c3 CC |
94 | * find_next_and_bit(addr1, addr2, nbits, bit) |
95 | * Same as find_next_bit, but in | |
96 | * (*addr1 & *addr2) | |
1da177e4 | 97 | * |
1da177e4 LT |
98 | */ |
99 | ||
7d7363e4 RD |
100 | /** |
101 | * DOC: declare bitmap | |
1da177e4 LT |
102 | * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used |
103 | * to declare an array named 'name' of just enough unsigned longs to | |
104 | * contain all bit positions from 0 to 'bits' - 1. | |
105 | */ | |
106 | ||
c42b65e3 AS |
107 | /* |
108 | * Allocation and deallocation of bitmap. | |
109 | * Provided in lib/bitmap.c to avoid circular dependency. | |
110 | */ | |
111 | extern unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags); | |
112 | extern unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags); | |
113 | extern void bitmap_free(const unsigned long *bitmap); | |
114 | ||
1da177e4 LT |
115 | /* |
116 | * lib/bitmap.c provides these functions: | |
117 | */ | |
118 | ||
0679cc48 | 119 | extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits); |
8397927c | 120 | extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits); |
1da177e4 | 121 | extern int __bitmap_equal(const unsigned long *bitmap1, |
5e068069 | 122 | const unsigned long *bitmap2, unsigned int nbits); |
1da177e4 | 123 | extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, |
3d6684f4 | 124 | unsigned int nbits); |
2fbad299 RV |
125 | extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
126 | unsigned int shift, unsigned int nbits); | |
dba94c25 RV |
127 | extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
128 | unsigned int shift, unsigned int nbits); | |
f4b0373b | 129 | extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 130 | const unsigned long *bitmap2, unsigned int nbits); |
1da177e4 | 131 | extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 132 | const unsigned long *bitmap2, unsigned int nbits); |
1da177e4 | 133 | extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 134 | const unsigned long *bitmap2, unsigned int nbits); |
f4b0373b | 135 | extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 136 | const unsigned long *bitmap2, unsigned int nbits); |
1da177e4 | 137 | extern int __bitmap_intersects(const unsigned long *bitmap1, |
6dfe9799 | 138 | const unsigned long *bitmap2, unsigned int nbits); |
1da177e4 | 139 | extern int __bitmap_subset(const unsigned long *bitmap1, |
5be20213 | 140 | const unsigned long *bitmap2, unsigned int nbits); |
877d9f3b | 141 | extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); |
e5af323c MW |
142 | extern void __bitmap_set(unsigned long *map, unsigned int start, int len); |
143 | extern void __bitmap_clear(unsigned long *map, unsigned int start, int len); | |
5e19b013 MN |
144 | |
145 | extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map, | |
146 | unsigned long size, | |
147 | unsigned long start, | |
148 | unsigned int nr, | |
149 | unsigned long align_mask, | |
150 | unsigned long align_offset); | |
151 | ||
152 | /** | |
153 | * bitmap_find_next_zero_area - find a contiguous aligned zero area | |
154 | * @map: The address to base the search on | |
155 | * @size: The bitmap size in bits | |
156 | * @start: The bitnumber to start searching at | |
157 | * @nr: The number of zeroed bits we're looking for | |
158 | * @align_mask: Alignment mask for zero area | |
159 | * | |
160 | * The @align_mask should be one less than a power of 2; the effect is that | |
161 | * the bit offset of all zero areas this function finds is multiples of that | |
162 | * power of 2. A @align_mask of 0 means no alignment is required. | |
163 | */ | |
164 | static inline unsigned long | |
165 | bitmap_find_next_zero_area(unsigned long *map, | |
166 | unsigned long size, | |
167 | unsigned long start, | |
168 | unsigned int nr, | |
169 | unsigned long align_mask) | |
170 | { | |
171 | return bitmap_find_next_zero_area_off(map, size, start, nr, | |
172 | align_mask, 0); | |
173 | } | |
c1a2a962 | 174 | |
01a3ee2b RC |
175 | extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user, |
176 | unsigned long *dst, int nbits); | |
177 | extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, | |
1da177e4 | 178 | unsigned long *dst, int nbits); |
1da177e4 LT |
179 | extern int bitmap_parselist(const char *buf, unsigned long *maskp, |
180 | int nmaskbits); | |
4b060420 MT |
181 | extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, |
182 | unsigned long *dst, int nbits); | |
fb5eeeee | 183 | extern void bitmap_remap(unsigned long *dst, const unsigned long *src, |
9814ec13 | 184 | const unsigned long *old, const unsigned long *new, unsigned int nbits); |
fb5eeeee PJ |
185 | extern int bitmap_bitremap(int oldbit, |
186 | const unsigned long *old, const unsigned long *new, int bits); | |
7ea931c9 | 187 | extern void bitmap_onto(unsigned long *dst, const unsigned long *orig, |
eb569883 | 188 | const unsigned long *relmap, unsigned int bits); |
7ea931c9 | 189 | extern void bitmap_fold(unsigned long *dst, const unsigned long *orig, |
b26ad583 | 190 | unsigned int sz, unsigned int nbits); |
9279d328 RV |
191 | extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order); |
192 | extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order); | |
193 | extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order); | |
3aa56885 | 194 | |
e8f24278 | 195 | #ifdef __BIG_ENDIAN |
9b6c2d2e | 196 | extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits); |
e8f24278 RV |
197 | #else |
198 | #define bitmap_copy_le bitmap_copy | |
199 | #endif | |
f6a1f5db | 200 | extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits); |
5aaba363 SH |
201 | extern int bitmap_print_to_pagebuf(bool list, char *buf, |
202 | const unsigned long *maskp, int nmaskbits); | |
1da177e4 | 203 | |
89c1e79e RV |
204 | #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) |
205 | #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) | |
1da177e4 | 206 | |
7275b097 RV |
207 | /* |
208 | * The static inlines below do not handle constant nbits==0 correctly, | |
209 | * so make such users (should any ever turn up) call the out-of-line | |
210 | * versions. | |
211 | */ | |
4b0bc0bc | 212 | #define small_const_nbits(nbits) \ |
7275b097 | 213 | (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG && (nbits) > 0) |
4b0bc0bc | 214 | |
8b4daad5 | 215 | static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) |
1da177e4 | 216 | { |
c8cebc55 RV |
217 | unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); |
218 | memset(dst, 0, len); | |
1da177e4 LT |
219 | } |
220 | ||
8b4daad5 | 221 | static inline void bitmap_fill(unsigned long *dst, unsigned int nbits) |
1da177e4 | 222 | { |
c8cebc55 RV |
223 | unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); |
224 | memset(dst, 0xff, len); | |
1da177e4 LT |
225 | } |
226 | ||
227 | static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, | |
8b4daad5 | 228 | unsigned int nbits) |
1da177e4 | 229 | { |
c8cebc55 RV |
230 | unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); |
231 | memcpy(dst, src, len); | |
1da177e4 LT |
232 | } |
233 | ||
c724f193 YN |
234 | /* |
235 | * Copy bitmap and clear tail bits in last word. | |
236 | */ | |
237 | static inline void bitmap_copy_clear_tail(unsigned long *dst, | |
238 | const unsigned long *src, unsigned int nbits) | |
239 | { | |
240 | bitmap_copy(dst, src, nbits); | |
241 | if (nbits % BITS_PER_LONG) | |
242 | dst[nbits / BITS_PER_LONG] &= BITMAP_LAST_WORD_MASK(nbits); | |
243 | } | |
244 | ||
245 | /* | |
246 | * On 32-bit systems bitmaps are represented as u32 arrays internally, and | |
247 | * therefore conversion is not needed when copying data from/to arrays of u32. | |
248 | */ | |
249 | #if BITS_PER_LONG == 64 | |
250 | extern void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, | |
251 | unsigned int nbits); | |
252 | extern void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, | |
253 | unsigned int nbits); | |
254 | #else | |
255 | #define bitmap_from_arr32(bitmap, buf, nbits) \ | |
256 | bitmap_copy_clear_tail((unsigned long *) (bitmap), \ | |
257 | (const unsigned long *) (buf), (nbits)) | |
258 | #define bitmap_to_arr32(buf, bitmap, nbits) \ | |
259 | bitmap_copy_clear_tail((unsigned long *) (buf), \ | |
260 | (const unsigned long *) (bitmap), (nbits)) | |
261 | #endif | |
262 | ||
f4b0373b | 263 | static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, |
2f9305eb | 264 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 265 | { |
4b0bc0bc | 266 | if (small_const_nbits(nbits)) |
7e5f97d1 | 267 | return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0; |
f4b0373b | 268 | return __bitmap_and(dst, src1, src2, nbits); |
1da177e4 LT |
269 | } |
270 | ||
271 | static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, | |
2f9305eb | 272 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 273 | { |
4b0bc0bc | 274 | if (small_const_nbits(nbits)) |
1da177e4 LT |
275 | *dst = *src1 | *src2; |
276 | else | |
277 | __bitmap_or(dst, src1, src2, nbits); | |
278 | } | |
279 | ||
280 | static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, | |
2f9305eb | 281 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 282 | { |
4b0bc0bc | 283 | if (small_const_nbits(nbits)) |
1da177e4 LT |
284 | *dst = *src1 ^ *src2; |
285 | else | |
286 | __bitmap_xor(dst, src1, src2, nbits); | |
287 | } | |
288 | ||
f4b0373b | 289 | static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, |
2f9305eb | 290 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 291 | { |
4b0bc0bc | 292 | if (small_const_nbits(nbits)) |
74e76531 | 293 | return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; |
f4b0373b | 294 | return __bitmap_andnot(dst, src1, src2, nbits); |
1da177e4 LT |
295 | } |
296 | ||
297 | static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, | |
3d6684f4 | 298 | unsigned int nbits) |
1da177e4 | 299 | { |
4b0bc0bc | 300 | if (small_const_nbits(nbits)) |
65b4ee62 | 301 | *dst = ~(*src); |
1da177e4 LT |
302 | else |
303 | __bitmap_complement(dst, src, nbits); | |
304 | } | |
305 | ||
21035965 OS |
306 | #ifdef __LITTLE_ENDIAN |
307 | #define BITMAP_MEM_ALIGNMENT 8 | |
308 | #else | |
309 | #define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long)) | |
310 | #endif | |
311 | #define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1) | |
312 | ||
1da177e4 | 313 | static inline int bitmap_equal(const unsigned long *src1, |
3d6684f4 | 314 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 315 | { |
4b0bc0bc | 316 | if (small_const_nbits(nbits)) |
4b9d314c | 317 | return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); |
21035965 OS |
318 | if (__builtin_constant_p(nbits & BITMAP_MEM_MASK) && |
319 | IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) | |
7dd96816 | 320 | return !memcmp(src1, src2, nbits / 8); |
4b9d314c | 321 | return __bitmap_equal(src1, src2, nbits); |
1da177e4 LT |
322 | } |
323 | ||
324 | static inline int bitmap_intersects(const unsigned long *src1, | |
6dfe9799 | 325 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 326 | { |
4b0bc0bc | 327 | if (small_const_nbits(nbits)) |
1da177e4 LT |
328 | return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; |
329 | else | |
330 | return __bitmap_intersects(src1, src2, nbits); | |
331 | } | |
332 | ||
333 | static inline int bitmap_subset(const unsigned long *src1, | |
5be20213 | 334 | const unsigned long *src2, unsigned int nbits) |
1da177e4 | 335 | { |
4b0bc0bc | 336 | if (small_const_nbits(nbits)) |
1da177e4 LT |
337 | return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); |
338 | else | |
339 | return __bitmap_subset(src1, src2, nbits); | |
340 | } | |
341 | ||
0679cc48 | 342 | static inline int bitmap_empty(const unsigned long *src, unsigned nbits) |
1da177e4 | 343 | { |
4b0bc0bc | 344 | if (small_const_nbits(nbits)) |
1da177e4 | 345 | return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); |
2afe27c7 YN |
346 | |
347 | return find_first_bit(src, nbits) == nbits; | |
1da177e4 LT |
348 | } |
349 | ||
8397927c | 350 | static inline int bitmap_full(const unsigned long *src, unsigned int nbits) |
1da177e4 | 351 | { |
4b0bc0bc | 352 | if (small_const_nbits(nbits)) |
1da177e4 | 353 | return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); |
2afe27c7 YN |
354 | |
355 | return find_first_zero_bit(src, nbits) == nbits; | |
1da177e4 LT |
356 | } |
357 | ||
1a1d48a4 | 358 | static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits) |
1da177e4 | 359 | { |
4b0bc0bc | 360 | if (small_const_nbits(nbits)) |
08cd3657 | 361 | return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits)); |
1da177e4 LT |
362 | return __bitmap_weight(src, nbits); |
363 | } | |
364 | ||
e5af323c MW |
365 | static __always_inline void bitmap_set(unsigned long *map, unsigned int start, |
366 | unsigned int nbits) | |
367 | { | |
368 | if (__builtin_constant_p(nbits) && nbits == 1) | |
369 | __set_bit(start, map); | |
21035965 OS |
370 | else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && |
371 | IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && | |
372 | __builtin_constant_p(nbits & BITMAP_MEM_MASK) && | |
373 | IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) | |
2a98dc02 | 374 | memset((char *)map + start / 8, 0xff, nbits / 8); |
e5af323c MW |
375 | else |
376 | __bitmap_set(map, start, nbits); | |
377 | } | |
378 | ||
379 | static __always_inline void bitmap_clear(unsigned long *map, unsigned int start, | |
380 | unsigned int nbits) | |
381 | { | |
382 | if (__builtin_constant_p(nbits) && nbits == 1) | |
383 | __clear_bit(start, map); | |
21035965 OS |
384 | else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && |
385 | IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && | |
386 | __builtin_constant_p(nbits & BITMAP_MEM_MASK) && | |
387 | IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) | |
2a98dc02 | 388 | memset((char *)map + start / 8, 0, nbits / 8); |
e5af323c MW |
389 | else |
390 | __bitmap_clear(map, start, nbits); | |
391 | } | |
392 | ||
2fbad299 | 393 | static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
d9873969 | 394 | unsigned int shift, unsigned int nbits) |
1da177e4 | 395 | { |
4b0bc0bc | 396 | if (small_const_nbits(nbits)) |
2fbad299 | 397 | *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift; |
1da177e4 | 398 | else |
2fbad299 | 399 | __bitmap_shift_right(dst, src, shift, nbits); |
1da177e4 LT |
400 | } |
401 | ||
dba94c25 RV |
402 | static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
403 | unsigned int shift, unsigned int nbits) | |
1da177e4 | 404 | { |
4b0bc0bc | 405 | if (small_const_nbits(nbits)) |
dba94c25 | 406 | *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits); |
1da177e4 | 407 | else |
dba94c25 | 408 | __bitmap_shift_left(dst, src, shift, nbits); |
1da177e4 LT |
409 | } |
410 | ||
01a3ee2b RC |
411 | static inline int bitmap_parse(const char *buf, unsigned int buflen, |
412 | unsigned long *maskp, int nmaskbits) | |
413 | { | |
414 | return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits); | |
415 | } | |
416 | ||
404376af | 417 | /** |
60ef6900 | 418 | * BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap. |
404376af | 419 | * @n: u64 value |
60ef6900 YN |
420 | * |
421 | * Linux bitmaps are internally arrays of unsigned longs, i.e. 32-bit | |
422 | * integers in 32-bit environment, and 64-bit integers in 64-bit one. | |
423 | * | |
424 | * There are four combinations of endianness and length of the word in linux | |
425 | * ABIs: LE64, BE64, LE32 and BE32. | |
426 | * | |
427 | * On 64-bit kernels 64-bit LE and BE numbers are naturally ordered in | |
428 | * bitmaps and therefore don't require any special handling. | |
429 | * | |
430 | * On 32-bit kernels 32-bit LE ABI orders lo word of 64-bit number in memory | |
431 | * prior to hi, and 32-bit BE orders hi word prior to lo. The bitmap on the | |
432 | * other hand is represented as an array of 32-bit words and the position of | |
433 | * bit N may therefore be calculated as: word #(N/32) and bit #(N%32) in that | |
434 | * word. For example, bit #42 is located at 10th position of 2nd word. | |
435 | * It matches 32-bit LE ABI, and we can simply let the compiler store 64-bit | |
436 | * values in memory as it usually does. But for BE we need to swap hi and lo | |
437 | * words manually. | |
438 | * | |
439 | * With all that, the macro BITMAP_FROM_U64() does explicit reordering of hi and | |
440 | * lo parts of u64. For LE32 it does nothing, and for BE environment it swaps | |
441 | * hi and lo words, as is expected by bitmap. | |
442 | */ | |
443 | #if __BITS_PER_LONG == 64 | |
444 | #define BITMAP_FROM_U64(n) (n) | |
445 | #else | |
446 | #define BITMAP_FROM_U64(n) ((unsigned long) ((u64)(n) & ULONG_MAX)), \ | |
447 | ((unsigned long) ((u64)(n) >> 32)) | |
448 | #endif | |
449 | ||
404376af | 450 | /** |
29dd3288 MS |
451 | * bitmap_from_u64 - Check and swap words within u64. |
452 | * @mask: source bitmap | |
453 | * @dst: destination bitmap | |
454 | * | |
404376af | 455 | * In 32-bit Big Endian kernel, when using ``(u32 *)(&val)[*]`` |
29dd3288 | 456 | * to read u64 mask, we will get the wrong word. |
404376af | 457 | * That is ``(u32 *)(&val)[0]`` gets the upper 32 bits, |
29dd3288 MS |
458 | * but we expect the lower 32-bits of u64. |
459 | */ | |
460 | static inline void bitmap_from_u64(unsigned long *dst, u64 mask) | |
461 | { | |
462 | dst[0] = mask & ULONG_MAX; | |
463 | ||
464 | if (sizeof(mask) > sizeof(unsigned long)) | |
465 | dst[1] = mask >> 32; | |
466 | } | |
467 | ||
1da177e4 LT |
468 | #endif /* __ASSEMBLY__ */ |
469 | ||
470 | #endif /* __LINUX_BITMAP_H */ |