1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef __LINUX_BITMAP_H |
3 | #define __LINUX_BITMAP_H |
4 | |
5 | #ifndef __ASSEMBLY__ |
6 | |
7 | #include <linux/align.h> |
8 | #include <linux/bitops.h> |
9 | #include <linux/errno.h> |
10 | #include <linux/find.h> |
11 | #include <linux/limits.h> |
12 | #include <linux/string.h> |
13 | #include <linux/types.h> |
14 | #include <linux/bitmap-str.h> |
15 | |
16 | struct device; |
17 | |
18 | /* |
19 | * bitmaps provide bit arrays that consume one or more unsigned |
20 | * longs. The bitmap interface and available operations are listed |
21 | * here, in bitmap.h |
22 | * |
23 | * Function implementations generic to all architectures are in |
24 | * lib/bitmap.c. Functions implementations that are architecture |
25 | * specific are in various include/asm-<arch>/bitops.h headers |
26 | * and other arch/<arch> specific files. |
27 | * |
28 | * See lib/bitmap.c for more details. |
29 | */ |
30 | |
31 | /** |
32 | * DOC: bitmap overview |
33 | * |
34 | * The available bitmap operations and their rough meaning in the |
35 | * case that the bitmap is a single unsigned long are thus: |
36 | * |
37 | * The generated code is more efficient when nbits is known at |
38 | * compile-time and at most BITS_PER_LONG. |
39 | * |
40 | * :: |
41 | * |
42 | * bitmap_zero(dst, nbits) *dst = 0UL |
43 | * bitmap_fill(dst, nbits) *dst = ~0UL |
44 | * bitmap_copy(dst, src, nbits) *dst = *src |
45 | * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 |
46 | * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 |
47 | * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 |
48 | * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) |
49 | * bitmap_complement(dst, src, nbits) *dst = ~(*src) |
50 | * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal? |
51 | * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap? |
52 | * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2? |
53 | * bitmap_empty(src, nbits) Are all bits zero in *src? |
54 | * bitmap_full(src, nbits) Are all bits set in *src? |
55 | * bitmap_weight(src, nbits) Hamming Weight: number set bits |
56 | * bitmap_weight_and(src1, src2, nbits) Hamming Weight of and'ed bitmap |
57 | * bitmap_set(dst, pos, nbits) Set specified bit area |
58 | * bitmap_clear(dst, pos, nbits) Clear specified bit area |
59 | * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area |
60 | * bitmap_find_next_zero_area_off(buf, len, pos, n, mask, mask_off) as above |
61 | * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n |
62 | * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n |
63 | * bitmap_cut(dst, src, first, n, nbits) Cut n bits from first, copy rest |
64 | * bitmap_replace(dst, old, new, mask, nbits) *dst = (*old & ~(*mask)) | (*new & *mask) |
65 | * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src) |
66 | * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit) |
67 | * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap |
68 | * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz |
69 | * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf |
70 | * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf |
71 | * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf |
72 | * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf |
73 | * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region |
74 | * bitmap_release_region(bitmap, pos, order) Free specified bit region |
75 | * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region |
76 | * bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst |
77 | * bitmap_from_arr64(dst, buf, nbits) Copy nbits from u64[] buf to dst |
78 | * bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst |
79 | * bitmap_to_arr64(buf, src, nbits) Copy nbits from buf to u64[] dst |
80 | * bitmap_get_value8(map, start) Get 8bit value from map at start |
81 | * bitmap_set_value8(map, value, start) Set 8bit value to map at start |
82 | * |
83 | * Note, bitmap_zero() and bitmap_fill() operate over the region of |
84 | * unsigned longs, that is, bits behind bitmap till the unsigned long |
85 | * boundary will be zeroed or filled as well. Consider to use |
86 | * bitmap_clear() or bitmap_set() to make explicit zeroing or filling |
87 | * respectively. |
88 | */ |
89 | |
90 | /** |
91 | * DOC: bitmap bitops |
92 | * |
93 | * Also the following operations in asm/bitops.h apply to bitmaps.:: |
94 | * |
95 | * set_bit(bit, addr) *addr |= bit |
96 | * clear_bit(bit, addr) *addr &= ~bit |
97 | * change_bit(bit, addr) *addr ^= bit |
98 | * test_bit(bit, addr) Is bit set in *addr? |
99 | * test_and_set_bit(bit, addr) Set bit and return old value |
100 | * test_and_clear_bit(bit, addr) Clear bit and return old value |
101 | * test_and_change_bit(bit, addr) Change bit and return old value |
102 | * find_first_zero_bit(addr, nbits) Position first zero bit in *addr |
103 | * find_first_bit(addr, nbits) Position first set bit in *addr |
104 | * find_next_zero_bit(addr, nbits, bit) |
105 | * Position next zero bit in *addr >= bit |
106 | * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit |
107 | * find_next_and_bit(addr1, addr2, nbits, bit) |
108 | * Same as find_next_bit, but in |
109 | * (*addr1 & *addr2) |
110 | * |
111 | */ |
112 | |
113 | /** |
114 | * DOC: declare bitmap |
115 | * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used |
116 | * to declare an array named 'name' of just enough unsigned longs to |
117 | * contain all bit positions from 0 to 'bits' - 1. |
118 | */ |
119 | |
120 | /* |
121 | * Allocation and deallocation of bitmap. |
122 | * Provided in lib/bitmap.c to avoid circular dependency. |
123 | */ |
124 | unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags); |
125 | unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags); |
126 | unsigned long *bitmap_alloc_node(unsigned int nbits, gfp_t flags, int node); |
127 | unsigned long *bitmap_zalloc_node(unsigned int nbits, gfp_t flags, int node); |
128 | void bitmap_free(const unsigned long *bitmap); |
129 | |
130 | /* Managed variants of the above. */ |
131 | unsigned long *devm_bitmap_alloc(struct device *dev, |
132 | unsigned int nbits, gfp_t flags); |
133 | unsigned long *devm_bitmap_zalloc(struct device *dev, |
134 | unsigned int nbits, gfp_t flags); |
135 | |
136 | /* |
137 | * lib/bitmap.c provides these functions: |
138 | */ |
139 | |
140 | bool __bitmap_equal(const unsigned long *bitmap1, |
141 | const unsigned long *bitmap2, unsigned int nbits); |
142 | bool __pure __bitmap_or_equal(const unsigned long *src1, |
143 | const unsigned long *src2, |
144 | const unsigned long *src3, |
145 | unsigned int nbits); |
146 | void __bitmap_complement(unsigned long *dst, const unsigned long *src, |
147 | unsigned int nbits); |
148 | void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
149 | unsigned int shift, unsigned int nbits); |
150 | void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
151 | unsigned int shift, unsigned int nbits); |
152 | void bitmap_cut(unsigned long *dst, const unsigned long *src, |
153 | unsigned int first, unsigned int cut, unsigned int nbits); |
154 | bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
155 | const unsigned long *bitmap2, unsigned int nbits); |
156 | void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, |
157 | const unsigned long *bitmap2, unsigned int nbits); |
158 | void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, |
159 | const unsigned long *bitmap2, unsigned int nbits); |
160 | bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
161 | const unsigned long *bitmap2, unsigned int nbits); |
162 | void __bitmap_replace(unsigned long *dst, |
163 | const unsigned long *old, const unsigned long *new, |
164 | const unsigned long *mask, unsigned int nbits); |
165 | bool __bitmap_intersects(const unsigned long *bitmap1, |
166 | const unsigned long *bitmap2, unsigned int nbits); |
167 | bool __bitmap_subset(const unsigned long *bitmap1, |
168 | const unsigned long *bitmap2, unsigned int nbits); |
169 | unsigned int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); |
170 | unsigned int __bitmap_weight_and(const unsigned long *bitmap1, |
171 | const unsigned long *bitmap2, unsigned int nbits); |
172 | void __bitmap_set(unsigned long *map, unsigned int start, int len); |
173 | void __bitmap_clear(unsigned long *map, unsigned int start, int len); |
174 | |
175 | unsigned long bitmap_find_next_zero_area_off(unsigned long *map, |
176 | unsigned long size, |
177 | unsigned long start, |
178 | unsigned int nr, |
179 | unsigned long align_mask, |
180 | unsigned long align_offset); |
181 | |
182 | /** |
183 | * bitmap_find_next_zero_area - find a contiguous aligned zero area |
184 | * @map: The address to base the search on |
185 | * @size: The bitmap size in bits |
186 | * @start: The bitnumber to start searching at |
187 | * @nr: The number of zeroed bits we're looking for |
188 | * @align_mask: Alignment mask for zero area |
189 | * |
190 | * The @align_mask should be one less than a power of 2; the effect is that |
191 | * the bit offset of all zero areas this function finds is multiples of that |
192 | * power of 2. A @align_mask of 0 means no alignment is required. |
193 | */ |
194 | static inline unsigned long |
195 | bitmap_find_next_zero_area(unsigned long *map, |
196 | unsigned long size, |
197 | unsigned long start, |
198 | unsigned int nr, |
199 | unsigned long align_mask) |
200 | { |
201 | return bitmap_find_next_zero_area_off(map, size, start, nr, |
202 | align_mask, align_offset: 0); |
203 | } |
204 | |
205 | void bitmap_remap(unsigned long *dst, const unsigned long *src, |
206 | const unsigned long *old, const unsigned long *new, unsigned int nbits); |
207 | int bitmap_bitremap(int oldbit, |
208 | const unsigned long *old, const unsigned long *new, int bits); |
209 | void bitmap_onto(unsigned long *dst, const unsigned long *orig, |
210 | const unsigned long *relmap, unsigned int bits); |
211 | void bitmap_fold(unsigned long *dst, const unsigned long *orig, |
212 | unsigned int sz, unsigned int nbits); |
213 | |
214 | #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) |
215 | #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) |
216 | |
217 | static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) |
218 | { |
219 | unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); |
220 | |
221 | if (small_const_nbits(nbits)) |
222 | *dst = 0; |
223 | else |
224 | memset(dst, 0, len); |
225 | } |
226 | |
227 | static inline void bitmap_fill(unsigned long *dst, unsigned int nbits) |
228 | { |
229 | unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); |
230 | |
231 | if (small_const_nbits(nbits)) |
232 | *dst = ~0UL; |
233 | else |
234 | memset(dst, 0xff, len); |
235 | } |
236 | |
237 | static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, |
238 | unsigned int nbits) |
239 | { |
240 | unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); |
241 | |
242 | if (small_const_nbits(nbits)) |
243 | *dst = *src; |
244 | else |
245 | memcpy(dst, src, len); |
246 | } |
247 | |
248 | /* |
249 | * Copy bitmap and clear tail bits in last word. |
250 | */ |
251 | static inline void bitmap_copy_clear_tail(unsigned long *dst, |
252 | const unsigned long *src, unsigned int nbits) |
253 | { |
254 | bitmap_copy(dst, src, nbits); |
255 | if (nbits % BITS_PER_LONG) |
256 | dst[nbits / BITS_PER_LONG] &= BITMAP_LAST_WORD_MASK(nbits); |
257 | } |
258 | |
259 | /* |
260 | * On 32-bit systems bitmaps are represented as u32 arrays internally. On LE64 |
261 | * machines the order of hi and lo parts of numbers match the bitmap structure. |
262 | * In both cases conversion is not needed when copying data from/to arrays of |
263 | * u32. But in LE64 case, typecast in bitmap_copy_clear_tail() may lead |
264 | * to out-of-bound access. To avoid that, both LE and BE variants of 64-bit |
265 | * architectures are not using bitmap_copy_clear_tail(). |
266 | */ |
267 | #if BITS_PER_LONG == 64 |
268 | void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, |
269 | unsigned int nbits); |
270 | void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, |
271 | unsigned int nbits); |
272 | #else |
273 | #define bitmap_from_arr32(bitmap, buf, nbits) \ |
274 | bitmap_copy_clear_tail((unsigned long *) (bitmap), \ |
275 | (const unsigned long *) (buf), (nbits)) |
276 | #define bitmap_to_arr32(buf, bitmap, nbits) \ |
277 | bitmap_copy_clear_tail((unsigned long *) (buf), \ |
278 | (const unsigned long *) (bitmap), (nbits)) |
279 | #endif |
280 | |
281 | /* |
282 | * On 64-bit systems bitmaps are represented as u64 arrays internally. So, |
283 | * the conversion is not needed when copying data from/to arrays of u64. |
284 | */ |
285 | #if BITS_PER_LONG == 32 |
286 | void bitmap_from_arr64(unsigned long *bitmap, const u64 *buf, unsigned int nbits); |
287 | void bitmap_to_arr64(u64 *buf, const unsigned long *bitmap, unsigned int nbits); |
288 | #else |
289 | #define bitmap_from_arr64(bitmap, buf, nbits) \ |
290 | bitmap_copy_clear_tail((unsigned long *)(bitmap), (const unsigned long *)(buf), (nbits)) |
291 | #define bitmap_to_arr64(buf, bitmap, nbits) \ |
292 | bitmap_copy_clear_tail((unsigned long *)(buf), (const unsigned long *)(bitmap), (nbits)) |
293 | #endif |
294 | |
295 | static inline bool bitmap_and(unsigned long *dst, const unsigned long *src1, |
296 | const unsigned long *src2, unsigned int nbits) |
297 | { |
298 | if (small_const_nbits(nbits)) |
299 | return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0; |
300 | return __bitmap_and(dst, bitmap1: src1, bitmap2: src2, nbits); |
301 | } |
302 | |
303 | static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, |
304 | const unsigned long *src2, unsigned int nbits) |
305 | { |
306 | if (small_const_nbits(nbits)) |
307 | *dst = *src1 | *src2; |
308 | else |
309 | __bitmap_or(dst, bitmap1: src1, bitmap2: src2, nbits); |
310 | } |
311 | |
312 | static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, |
313 | const unsigned long *src2, unsigned int nbits) |
314 | { |
315 | if (small_const_nbits(nbits)) |
316 | *dst = *src1 ^ *src2; |
317 | else |
318 | __bitmap_xor(dst, bitmap1: src1, bitmap2: src2, nbits); |
319 | } |
320 | |
321 | static inline bool bitmap_andnot(unsigned long *dst, const unsigned long *src1, |
322 | const unsigned long *src2, unsigned int nbits) |
323 | { |
324 | if (small_const_nbits(nbits)) |
325 | return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; |
326 | return __bitmap_andnot(dst, bitmap1: src1, bitmap2: src2, nbits); |
327 | } |
328 | |
329 | static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, |
330 | unsigned int nbits) |
331 | { |
332 | if (small_const_nbits(nbits)) |
333 | *dst = ~(*src); |
334 | else |
335 | __bitmap_complement(dst, src, nbits); |
336 | } |
337 | |
338 | #ifdef __LITTLE_ENDIAN |
339 | #define BITMAP_MEM_ALIGNMENT 8 |
340 | #else |
341 | #define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long)) |
342 | #endif |
343 | #define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1) |
344 | |
345 | static inline bool bitmap_equal(const unsigned long *src1, |
346 | const unsigned long *src2, unsigned int nbits) |
347 | { |
348 | if (small_const_nbits(nbits)) |
349 | return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); |
350 | if (__builtin_constant_p(nbits & BITMAP_MEM_MASK) && |
351 | IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) |
352 | return !memcmp(p: src1, q: src2, size: nbits / 8); |
353 | return __bitmap_equal(bitmap1: src1, bitmap2: src2, nbits); |
354 | } |
355 | |
356 | /** |
357 | * bitmap_or_equal - Check whether the or of two bitmaps is equal to a third |
358 | * @src1: Pointer to bitmap 1 |
359 | * @src2: Pointer to bitmap 2 will be or'ed with bitmap 1 |
360 | * @src3: Pointer to bitmap 3. Compare to the result of *@src1 | *@src2 |
361 | * @nbits: number of bits in each of these bitmaps |
362 | * |
363 | * Returns: True if (*@src1 | *@src2) == *@src3, false otherwise |
364 | */ |
365 | static inline bool bitmap_or_equal(const unsigned long *src1, |
366 | const unsigned long *src2, |
367 | const unsigned long *src3, |
368 | unsigned int nbits) |
369 | { |
370 | if (!small_const_nbits(nbits)) |
371 | return __bitmap_or_equal(src1, src2, src3, nbits); |
372 | |
373 | return !(((*src1 | *src2) ^ *src3) & BITMAP_LAST_WORD_MASK(nbits)); |
374 | } |
375 | |
376 | static inline bool bitmap_intersects(const unsigned long *src1, |
377 | const unsigned long *src2, |
378 | unsigned int nbits) |
379 | { |
380 | if (small_const_nbits(nbits)) |
381 | return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; |
382 | else |
383 | return __bitmap_intersects(bitmap1: src1, bitmap2: src2, nbits); |
384 | } |
385 | |
386 | static inline bool bitmap_subset(const unsigned long *src1, |
387 | const unsigned long *src2, unsigned int nbits) |
388 | { |
389 | if (small_const_nbits(nbits)) |
390 | return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); |
391 | else |
392 | return __bitmap_subset(bitmap1: src1, bitmap2: src2, nbits); |
393 | } |
394 | |
395 | static inline bool bitmap_empty(const unsigned long *src, unsigned nbits) |
396 | { |
397 | if (small_const_nbits(nbits)) |
398 | return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); |
399 | |
400 | return find_first_bit(addr: src, size: nbits) == nbits; |
401 | } |
402 | |
403 | static inline bool bitmap_full(const unsigned long *src, unsigned int nbits) |
404 | { |
405 | if (small_const_nbits(nbits)) |
406 | return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); |
407 | |
408 | return find_first_zero_bit(addr: src, size: nbits) == nbits; |
409 | } |
410 | |
411 | static __always_inline |
412 | unsigned int bitmap_weight(const unsigned long *src, unsigned int nbits) |
413 | { |
414 | if (small_const_nbits(nbits)) |
415 | return hweight_long(w: *src & BITMAP_LAST_WORD_MASK(nbits)); |
416 | return __bitmap_weight(bitmap: src, nbits); |
417 | } |
418 | |
419 | static __always_inline |
420 | unsigned long bitmap_weight_and(const unsigned long *src1, |
421 | const unsigned long *src2, unsigned int nbits) |
422 | { |
423 | if (small_const_nbits(nbits)) |
424 | return hweight_long(w: *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)); |
425 | return __bitmap_weight_and(bitmap1: src1, bitmap2: src2, nbits); |
426 | } |
427 | |
428 | static __always_inline void bitmap_set(unsigned long *map, unsigned int start, |
429 | unsigned int nbits) |
430 | { |
431 | if (__builtin_constant_p(nbits) && nbits == 1) |
432 | __set_bit(start, map); |
433 | else if (small_const_nbits(start + nbits)) |
434 | *map |= GENMASK(start + nbits - 1, start); |
435 | else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && |
436 | IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && |
437 | __builtin_constant_p(nbits & BITMAP_MEM_MASK) && |
438 | IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) |
439 | memset((char *)map + start / 8, 0xff, nbits / 8); |
440 | else |
441 | __bitmap_set(map, start, len: nbits); |
442 | } |
443 | |
444 | static __always_inline void bitmap_clear(unsigned long *map, unsigned int start, |
445 | unsigned int nbits) |
446 | { |
447 | if (__builtin_constant_p(nbits) && nbits == 1) |
448 | __clear_bit(start, map); |
449 | else if (small_const_nbits(start + nbits)) |
450 | *map &= ~GENMASK(start + nbits - 1, start); |
451 | else if (__builtin_constant_p(start & BITMAP_MEM_MASK) && |
452 | IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) && |
453 | __builtin_constant_p(nbits & BITMAP_MEM_MASK) && |
454 | IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT)) |
455 | memset((char *)map + start / 8, 0, nbits / 8); |
456 | else |
457 | __bitmap_clear(map, start, len: nbits); |
458 | } |
459 | |
460 | static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
461 | unsigned int shift, unsigned int nbits) |
462 | { |
463 | if (small_const_nbits(nbits)) |
464 | *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift; |
465 | else |
466 | __bitmap_shift_right(dst, src, shift, nbits); |
467 | } |
468 | |
469 | static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
470 | unsigned int shift, unsigned int nbits) |
471 | { |
472 | if (small_const_nbits(nbits)) |
473 | *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits); |
474 | else |
475 | __bitmap_shift_left(dst, src, shift, nbits); |
476 | } |
477 | |
478 | static inline void bitmap_replace(unsigned long *dst, |
479 | const unsigned long *old, |
480 | const unsigned long *new, |
481 | const unsigned long *mask, |
482 | unsigned int nbits) |
483 | { |
484 | if (small_const_nbits(nbits)) |
485 | *dst = (*old & ~(*mask)) | (*new & *mask); |
486 | else |
487 | __bitmap_replace(dst, old, new, mask, nbits); |
488 | } |
489 | |
490 | static inline void bitmap_next_set_region(unsigned long *bitmap, |
491 | unsigned int *rs, unsigned int *re, |
492 | unsigned int end) |
493 | { |
494 | *rs = find_next_bit(addr: bitmap, size: end, offset: *rs); |
495 | *re = find_next_zero_bit(addr: bitmap, size: end, offset: *rs + 1); |
496 | } |
497 | |
498 | /** |
499 | * bitmap_release_region - release allocated bitmap region |
500 | * @bitmap: array of unsigned longs corresponding to the bitmap |
501 | * @pos: beginning of bit region to release |
502 | * @order: region size (log base 2 of number of bits) to release |
503 | * |
504 | * This is the complement to __bitmap_find_free_region() and releases |
505 | * the found region (by clearing it in the bitmap). |
506 | */ |
507 | static inline void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) |
508 | { |
509 | bitmap_clear(map: bitmap, start: pos, BIT(order)); |
510 | } |
511 | |
512 | /** |
513 | * bitmap_allocate_region - allocate bitmap region |
514 | * @bitmap: array of unsigned longs corresponding to the bitmap |
515 | * @pos: beginning of bit region to allocate |
516 | * @order: region size (log base 2 of number of bits) to allocate |
517 | * |
518 | * Allocate (set bits in) a specified region of a bitmap. |
519 | * |
520 | * Returns: 0 on success, or %-EBUSY if specified region wasn't |
521 | * free (not all bits were zero). |
522 | */ |
523 | static inline int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) |
524 | { |
525 | unsigned int len = BIT(order); |
526 | |
527 | if (find_next_bit(addr: bitmap, size: pos + len, offset: pos) < pos + len) |
528 | return -EBUSY; |
529 | bitmap_set(map: bitmap, start: pos, nbits: len); |
530 | return 0; |
531 | } |
532 | |
533 | /** |
534 | * bitmap_find_free_region - find a contiguous aligned mem region |
535 | * @bitmap: array of unsigned longs corresponding to the bitmap |
536 | * @bits: number of bits in the bitmap |
537 | * @order: region size (log base 2 of number of bits) to find |
538 | * |
539 | * Find a region of free (zero) bits in a @bitmap of @bits bits and |
540 | * allocate them (set them to one). Only consider regions of length |
541 | * a power (@order) of two, aligned to that power of two, which |
542 | * makes the search algorithm much faster. |
543 | * |
544 | * Returns: the bit offset in bitmap of the allocated region, |
545 | * or -errno on failure. |
546 | */ |
547 | static inline int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) |
548 | { |
549 | unsigned int pos, end; /* scans bitmap by regions of size order */ |
550 | |
551 | for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) { |
552 | if (!bitmap_allocate_region(bitmap, pos, order)) |
553 | return pos; |
554 | } |
555 | return -ENOMEM; |
556 | } |
557 | |
558 | /** |
559 | * BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap. |
560 | * @n: u64 value |
561 | * |
562 | * Linux bitmaps are internally arrays of unsigned longs, i.e. 32-bit |
563 | * integers in 32-bit environment, and 64-bit integers in 64-bit one. |
564 | * |
565 | * There are four combinations of endianness and length of the word in linux |
566 | * ABIs: LE64, BE64, LE32 and BE32. |
567 | * |
568 | * On 64-bit kernels 64-bit LE and BE numbers are naturally ordered in |
569 | * bitmaps and therefore don't require any special handling. |
570 | * |
571 | * On 32-bit kernels 32-bit LE ABI orders lo word of 64-bit number in memory |
572 | * prior to hi, and 32-bit BE orders hi word prior to lo. The bitmap on the |
573 | * other hand is represented as an array of 32-bit words and the position of |
574 | * bit N may therefore be calculated as: word #(N/32) and bit #(N%32) in that |
575 | * word. For example, bit #42 is located at 10th position of 2nd word. |
576 | * It matches 32-bit LE ABI, and we can simply let the compiler store 64-bit |
577 | * values in memory as it usually does. But for BE we need to swap hi and lo |
578 | * words manually. |
579 | * |
580 | * With all that, the macro BITMAP_FROM_U64() does explicit reordering of hi and |
581 | * lo parts of u64. For LE32 it does nothing, and for BE environment it swaps |
582 | * hi and lo words, as is expected by bitmap. |
583 | */ |
584 | #if __BITS_PER_LONG == 64 |
585 | #define BITMAP_FROM_U64(n) (n) |
586 | #else |
587 | #define BITMAP_FROM_U64(n) ((unsigned long) ((u64)(n) & ULONG_MAX)), \ |
588 | ((unsigned long) ((u64)(n) >> 32)) |
589 | #endif |
590 | |
591 | /** |
592 | * bitmap_from_u64 - Check and swap words within u64. |
593 | * @mask: source bitmap |
594 | * @dst: destination bitmap |
595 | * |
596 | * In 32-bit Big Endian kernel, when using ``(u32 *)(&val)[*]`` |
597 | * to read u64 mask, we will get the wrong word. |
598 | * That is ``(u32 *)(&val)[0]`` gets the upper 32 bits, |
599 | * but we expect the lower 32-bits of u64. |
600 | */ |
601 | static inline void bitmap_from_u64(unsigned long *dst, u64 mask) |
602 | { |
603 | bitmap_from_arr64(dst, &mask, 64); |
604 | } |
605 | |
606 | /** |
607 | * bitmap_get_value8 - get an 8-bit value within a memory region |
608 | * @map: address to the bitmap memory region |
609 | * @start: bit offset of the 8-bit value; must be a multiple of 8 |
610 | * |
611 | * Returns the 8-bit value located at the @start bit offset within the @src |
612 | * memory region. |
613 | */ |
614 | static inline unsigned long bitmap_get_value8(const unsigned long *map, |
615 | unsigned long start) |
616 | { |
617 | const size_t index = BIT_WORD(start); |
618 | const unsigned long offset = start % BITS_PER_LONG; |
619 | |
620 | return (map[index] >> offset) & 0xFF; |
621 | } |
622 | |
623 | /** |
624 | * bitmap_set_value8 - set an 8-bit value within a memory region |
625 | * @map: address to the bitmap memory region |
626 | * @value: the 8-bit value; values wider than 8 bits may clobber bitmap |
627 | * @start: bit offset of the 8-bit value; must be a multiple of 8 |
628 | */ |
629 | static inline void bitmap_set_value8(unsigned long *map, unsigned long value, |
630 | unsigned long start) |
631 | { |
632 | const size_t index = BIT_WORD(start); |
633 | const unsigned long offset = start % BITS_PER_LONG; |
634 | |
635 | map[index] &= ~(0xFFUL << offset); |
636 | map[index] |= value << offset; |
637 | } |
638 | |
639 | #endif /* __ASSEMBLY__ */ |
640 | |
641 | #endif /* __LINUX_BITMAP_H */ |
642 | |