1 // SPDX-License-Identifier: GPL-2.0-only 1
2 /*
3 * lib/bitmap.c
4 * Helper functions for bitmap.h.
5 */
6
7 #include <linux/bitmap.h>
8 #include <linux/bitops.h>
9 #include <linux/ctype.h>
10 #include <linux/device.h>
11 #include <linux/export.h>
12 #include <linux/slab.h>
13
14 /**
15 * DOC: bitmap introduction
16 *
17 * bitmaps provide an array of bits, implement
18 * array of unsigned longs. The number of val
19 * given bitmap does _not_ need to be an exact
20 * BITS_PER_LONG.
21 *
22 * The possible unused bits in the last, parti
23 * of a bitmap are 'don't care'. The implemen
24 * no particular effort to keep them zero. It
25 * their value will not affect the results of
26 * The bitmap operations that return Boolean (
27 * for example) or scalar (bitmap_weight, for
28 * carefully filter out these unused bits from
29 * results.
30 *
31 * The byte ordering of bitmaps is more natura
32 * endian architectures. See the big-endian h
33 * include/asm-ppc64/bitops.h and include/asm-
34 * for the best explanations of this ordering.
35 */
36
37 bool __bitmap_equal(const unsigned long *bitma
38 const unsigned long *bitma
39 {
40 unsigned int k, lim = bits/BITS_PER_LO
41 for (k = 0; k < lim; ++k)
42 if (bitmap1[k] != bitmap2[k])
43 return false;
44
45 if (bits % BITS_PER_LONG)
46 if ((bitmap1[k] ^ bitmap2[k])
47 return false;
48
49 return true;
50 }
51 EXPORT_SYMBOL(__bitmap_equal);
52
53 bool __bitmap_or_equal(const unsigned long *bi
54 const unsigned long *bi
55 const unsigned long *bi
56 unsigned int bits)
57 {
58 unsigned int k, lim = bits / BITS_PER_
59 unsigned long tmp;
60
61 for (k = 0; k < lim; ++k) {
62 if ((bitmap1[k] | bitmap2[k])
63 return false;
64 }
65
66 if (!(bits % BITS_PER_LONG))
67 return true;
68
69 tmp = (bitmap1[k] | bitmap2[k]) ^ bitm
70 return (tmp & BITMAP_LAST_WORD_MASK(bi
71 }
72
73 void __bitmap_complement(unsigned long *dst, c
74 {
75 unsigned int k, lim = BITS_TO_LONGS(bi
76 for (k = 0; k < lim; ++k)
77 dst[k] = ~src[k];
78 }
79 EXPORT_SYMBOL(__bitmap_complement);
80
81 /**
82 * __bitmap_shift_right - logical right shift
83 * @dst : destination bitmap
84 * @src : source bitmap
85 * @shift : shift by this many bits
86 * @nbits : bitmap size, in bits
87 *
88 * Shifting right (dividing) means moving bits
89 * direction. Zeros are fed into the vacated
90 * LS bits shifted off the bottom are lost.
91 */
92 void __bitmap_shift_right(unsigned long *dst,
93 unsigned shift, unsign
94 {
95 unsigned k, lim = BITS_TO_LONGS(nbits)
96 unsigned off = shift/BITS_PER_LONG, re
97 unsigned long mask = BITMAP_LAST_WORD_
98 for (k = 0; off + k < lim; ++k) {
99 unsigned long upper, lower;
100
101 /*
102 * If shift is not word aligne
103 * word above and make them th
104 */
105 if (!rem || off + k + 1 >= lim
106 upper = 0;
107 else {
108 upper = src[off + k +
109 if (off + k + 1 == lim
110 upper &= mask;
111 upper <<= (BITS_PER_LO
112 }
113 lower = src[off + k];
114 if (off + k == lim - 1)
115 lower &= mask;
116 lower >>= rem;
117 dst[k] = lower | upper;
118 }
119 if (off)
120 memset(&dst[lim - off], 0, off
121 }
122 EXPORT_SYMBOL(__bitmap_shift_right);
123
124
125 /**
126 * __bitmap_shift_left - logical left shift of
127 * @dst : destination bitmap
128 * @src : source bitmap
129 * @shift : shift by this many bits
130 * @nbits : bitmap size, in bits
131 *
132 * Shifting left (multiplying) means moving bi
133 * direction. Zeros are fed into the vacated
134 * and those MS bits shifted off the top are l
135 */
136
137 void __bitmap_shift_left(unsigned long *dst, c
138 unsigned int shift, un
139 {
140 int k;
141 unsigned int lim = BITS_TO_LONGS(nbits
142 unsigned int off = shift/BITS_PER_LONG
143 for (k = lim - off - 1; k >= 0; --k) {
144 unsigned long upper, lower;
145
146 /*
147 * If shift is not word aligne
148 * word below and make them th
149 */
150 if (rem && k > 0)
151 lower = src[k - 1] >>
152 else
153 lower = 0;
154 upper = src[k] << rem;
155 dst[k + off] = lower | upper;
156 }
157 if (off)
158 memset(dst, 0, off*sizeof(unsi
159 }
160 EXPORT_SYMBOL(__bitmap_shift_left);
161
162 /**
163 * bitmap_cut() - remove bit region from bitma
164 * @dst: destination bitmap, might overlap wit
165 * @src: source bitmap
166 * @first: start bit of region to be removed
167 * @cut: number of bits to remove
168 * @nbits: bitmap size, in bits
169 *
170 * Set the n-th bit of @dst iff the n-th bit o
171 * n is less than @first, or the m-th bit of @
172 * m such that @first <= n < nbits, and m = n
173 *
174 * In pictures, example for a big-endian 32-bi
175 *
176 * The @src bitmap is::
177 *
178 * 31 63
179 * | |
180 * 10000000 11000001 11110010 00010101 1000
181 * | | |
182 * 16 14 0
183 *
184 * if @cut is 3, and @first is 14, bits 14-16
185 *
186 * 31 63
187 * | |
188 * 10110000 00011000 00110010 00010101 0001
189 * | |
190 * 14 (bit 17 0
191 * from @src)
192 *
193 * Note that @dst and @src might overlap parti
194 *
195 * This is implemented in the obvious way, wit
196 * step for each moved bit. Optimisation is le
197 * for the compiler.
198 */
199 void bitmap_cut(unsigned long *dst, const unsi
200 unsigned int first, unsigned i
201 {
202 unsigned int len = BITS_TO_LONGS(nbits
203 unsigned long keep = 0, carry;
204 int i;
205
206 if (first % BITS_PER_LONG) {
207 keep = src[first / BITS_PER_LO
208 (~0UL >> (BITS_PER_LONG
209 }
210
211 memmove(dst, src, len * sizeof(*dst));
212
213 while (cut--) {
214 for (i = first / BITS_PER_LONG
215 if (i < len - 1)
216 carry = dst[i
217 else
218 carry = 0;
219
220 dst[i] = (dst[i] >> 1)
221 }
222 }
223
224 dst[first / BITS_PER_LONG] &= ~0UL <<
225 dst[first / BITS_PER_LONG] |= keep;
226 }
227 EXPORT_SYMBOL(bitmap_cut);
228
229 bool __bitmap_and(unsigned long *dst, const un
230 const unsigned
231 {
232 unsigned int k;
233 unsigned int lim = bits/BITS_PER_LONG;
234 unsigned long result = 0;
235
236 for (k = 0; k < lim; k++)
237 result |= (dst[k] = bitmap1[k]
238 if (bits % BITS_PER_LONG)
239 result |= (dst[k] = bitmap1[k]
240 BITMAP_LAST_WORD_MA
241 return result != 0;
242 }
243 EXPORT_SYMBOL(__bitmap_and);
244
245 void __bitmap_or(unsigned long *dst, const uns
246 const unsigned
247 {
248 unsigned int k;
249 unsigned int nr = BITS_TO_LONGS(bits);
250
251 for (k = 0; k < nr; k++)
252 dst[k] = bitmap1[k] | bitmap2[
253 }
254 EXPORT_SYMBOL(__bitmap_or);
255
256 void __bitmap_xor(unsigned long *dst, const un
257 const unsigned
258 {
259 unsigned int k;
260 unsigned int nr = BITS_TO_LONGS(bits);
261
262 for (k = 0; k < nr; k++)
263 dst[k] = bitmap1[k] ^ bitmap2[
264 }
265 EXPORT_SYMBOL(__bitmap_xor);
266
267 bool __bitmap_andnot(unsigned long *dst, const
268 const unsigned
269 {
270 unsigned int k;
271 unsigned int lim = bits/BITS_PER_LONG;
272 unsigned long result = 0;
273
274 for (k = 0; k < lim; k++)
275 result |= (dst[k] = bitmap1[k]
276 if (bits % BITS_PER_LONG)
277 result |= (dst[k] = bitmap1[k]
278 BITMAP_LAST_WORD_MA
279 return result != 0;
280 }
281 EXPORT_SYMBOL(__bitmap_andnot);
282
283 void __bitmap_replace(unsigned long *dst,
284 const unsigned long *old
285 const unsigned long *mas
286 {
287 unsigned int k;
288 unsigned int nr = BITS_TO_LONGS(nbits)
289
290 for (k = 0; k < nr; k++)
291 dst[k] = (old[k] & ~mask[k]) |
292 }
293 EXPORT_SYMBOL(__bitmap_replace);
294
295 bool __bitmap_intersects(const unsigned long *
296 const unsigned long *
297 {
298 unsigned int k, lim = bits/BITS_PER_LO
299 for (k = 0; k < lim; ++k)
300 if (bitmap1[k] & bitmap2[k])
301 return true;
302
303 if (bits % BITS_PER_LONG)
304 if ((bitmap1[k] & bitmap2[k])
305 return true;
306 return false;
307 }
308 EXPORT_SYMBOL(__bitmap_intersects);
309
310 bool __bitmap_subset(const unsigned long *bitm
311 const unsigned long *bitm
312 {
313 unsigned int k, lim = bits/BITS_PER_LO
314 for (k = 0; k < lim; ++k)
315 if (bitmap1[k] & ~bitmap2[k])
316 return false;
317
318 if (bits % BITS_PER_LONG)
319 if ((bitmap1[k] & ~bitmap2[k])
320 return false;
321 return true;
322 }
323 EXPORT_SYMBOL(__bitmap_subset);
324
325 #define BITMAP_WEIGHT(FETCH, bits) \
326 ({
327 unsigned int __bits = (bits), idx, w =
328
329 for (idx = 0; idx < __bits / BITS_PER_
330 w += hweight_long(FETCH);
331
332 if (__bits % BITS_PER_LONG)
333 w += hweight_long((FETCH) & BI
334
335 w;
336 })
337
338 unsigned int __bitmap_weight(const unsigned lo
339 {
340 return BITMAP_WEIGHT(bitmap[idx], bits
341 }
342 EXPORT_SYMBOL(__bitmap_weight);
343
344 unsigned int __bitmap_weight_and(const unsigne
345 const unsigned
346 {
347 return BITMAP_WEIGHT(bitmap1[idx] & bi
348 }
349 EXPORT_SYMBOL(__bitmap_weight_and);
350
351 unsigned int __bitmap_weight_andnot(const unsi
352 const unsigned
353 {
354 return BITMAP_WEIGHT(bitmap1[idx] & ~b
355 }
356 EXPORT_SYMBOL(__bitmap_weight_andnot);
357
358 void __bitmap_set(unsigned long *map, unsigned
359 {
360 unsigned long *p = map + BIT_WORD(star
361 const unsigned int size = start + len;
362 int bits_to_set = BITS_PER_LONG - (sta
363 unsigned long mask_to_set = BITMAP_FIR
364
365 while (len - bits_to_set >= 0) {
366 *p |= mask_to_set;
367 len -= bits_to_set;
368 bits_to_set = BITS_PER_LONG;
369 mask_to_set = ~0UL;
370 p++;
371 }
372 if (len) {
373 mask_to_set &= BITMAP_LAST_WOR
374 *p |= mask_to_set;
375 }
376 }
377 EXPORT_SYMBOL(__bitmap_set);
378
379 void __bitmap_clear(unsigned long *map, unsign
380 {
381 unsigned long *p = map + BIT_WORD(star
382 const unsigned int size = start + len;
383 int bits_to_clear = BITS_PER_LONG - (s
384 unsigned long mask_to_clear = BITMAP_F
385
386 while (len - bits_to_clear >= 0) {
387 *p &= ~mask_to_clear;
388 len -= bits_to_clear;
389 bits_to_clear = BITS_PER_LONG;
390 mask_to_clear = ~0UL;
391 p++;
392 }
393 if (len) {
394 mask_to_clear &= BITMAP_LAST_W
395 *p &= ~mask_to_clear;
396 }
397 }
398 EXPORT_SYMBOL(__bitmap_clear);
399
400 /**
401 * bitmap_find_next_zero_area_off - find a con
402 * @map: The address to base the search on
403 * @size: The bitmap size in bits
404 * @start: The bitnumber to start searching at
405 * @nr: The number of zeroed bits we're lookin
406 * @align_mask: Alignment mask for zero area
407 * @align_offset: Alignment offset for zero ar
408 *
409 * The @align_mask should be one less than a p
410 * the bit offset of all zero areas this funct
411 * is multiple of that power of 2.
412 */
413 unsigned long bitmap_find_next_zero_area_off(u
414 u
415 u
416 u
417 u
418 u
419 {
420 unsigned long index, end, i;
421 again:
422 index = find_next_zero_bit(map, size,
423
424 /* Align allocation */
425 index = __ALIGN_MASK(index + align_off
426
427 end = index + nr;
428 if (end > size)
429 return end;
430 i = find_next_bit(map, end, index);
431 if (i < end) {
432 start = i + 1;
433 goto again;
434 }
435 return index;
436 }
437 EXPORT_SYMBOL(bitmap_find_next_zero_area_off);
438
439 /**
440 * bitmap_pos_to_ord - find ordinal of set bit
441 * @buf: pointer to a bitmap
442 * @pos: a bit position in @buf (0 <= @po
443 * @nbits: number of valid bit positions
444 *
445 * Map the bit at position @pos in @buf (of le
446 * ordinal of which set bit it is. If it is n
447 * is not a valid bit position, map to -1.
448 *
449 * If for example, just bits 4 through 7 are s
450 * values 4 through 7 will get mapped to 0 thr
451 * and other @pos values will get mapped to -1
452 * gets mapped to (returns) @ord value 3 in th
453 * that bit 7 is the 3rd (starting with 0th) s
454 *
455 * The bit positions 0 through @bits are valid
456 */
457 static int bitmap_pos_to_ord(const unsigned lo
458 {
459 if (pos >= nbits || !test_bit(pos, buf
460 return -1;
461
462 return bitmap_weight(buf, pos);
463 }
464
465 /**
466 * bitmap_remap - Apply map defined by a pair
467 * @dst: remapped result
468 * @src: subset to be remapped
469 * @old: defines domain of map
470 * @new: defines range of map
471 * @nbits: number of bits in each of thes
472 *
473 * Let @old and @new define a mapping of bit p
474 * whatever position is held by the n-th set b
475 * to the n-th set bit in @new. In the more g
476 * for the possibility that the weight 'w' of
477 * weight of @old, map the position of the n-t
478 * the position of the m-th set bit in @new, w
479 *
480 * If either of the @old and @new bitmaps are
481 * @dst point to the same location, then this
482 * to @dst.
483 *
484 * The positions of unset bits in @old are map
485 * (the identity map).
486 *
487 * Apply the above specified mapping to @src,
488 * @dst, clearing any bits previously set in @
489 *
490 * For example, lets say that @old has bits 4
491 * @new has bits 12 through 15 set. This defi
492 * position 4 to 12, 5 to 13, 6 to 14 and 7 to
493 * bit positions unchanged. So if say @src co
494 * with bits 1, 5 and 7 set, then @dst should
495 * 13 and 15 set.
496 */
497 void bitmap_remap(unsigned long *dst, const un
498 const unsigned long *old, cons
499 unsigned int nbits)
500 {
501 unsigned int oldbit, w;
502
503 if (dst == src) /* following d
504 return;
505 bitmap_zero(dst, nbits);
506
507 w = bitmap_weight(new, nbits);
508 for_each_set_bit(oldbit, src, nbits) {
509 int n = bitmap_pos_to_ord(old,
510
511 if (n < 0 || w == 0)
512 set_bit(oldbit, dst);
513 else
514 set_bit(find_nth_bit(n
515 }
516 }
517 EXPORT_SYMBOL(bitmap_remap);
518
519 /**
520 * bitmap_bitremap - Apply map defined by a pa
521 * @oldbit: bit position to be mapped
522 * @old: defines domain of map
523 * @new: defines range of map
524 * @bits: number of bits in each of these
525 *
526 * Let @old and @new define a mapping of bit p
527 * whatever position is held by the n-th set b
528 * to the n-th set bit in @new. In the more g
529 * for the possibility that the weight 'w' of
530 * weight of @old, map the position of the n-t
531 * the position of the m-th set bit in @new, w
532 *
533 * The positions of unset bits in @old are map
534 * (the identity map).
535 *
536 * Apply the above specified mapping to bit po
537 * the new bit position.
538 *
539 * For example, lets say that @old has bits 4
540 * @new has bits 12 through 15 set. This defi
541 * position 4 to 12, 5 to 13, 6 to 14 and 7 to
542 * bit positions unchanged. So if say @oldbit
543 * returns 13.
544 */
545 int bitmap_bitremap(int oldbit, const unsigned
546 const unsigned
547 {
548 int w = bitmap_weight(new, bits);
549 int n = bitmap_pos_to_ord(old, oldbit,
550 if (n < 0 || w == 0)
551 return oldbit;
552 else
553 return find_nth_bit(new, bits,
554 }
555 EXPORT_SYMBOL(bitmap_bitremap);
556
557 #ifdef CONFIG_NUMA
558 /**
559 * bitmap_onto - translate one bitmap relative
560 * @dst: resulting translated bitmap
561 * @orig: original untranslated bitmap
562 * @relmap: bitmap relative to which tran
563 * @bits: number of bits in each of these
564 *
565 * Set the n-th bit of @dst iff there exists s
566 * n-th bit of @relmap is set, the m-th bit of
567 * the n-th bit of @relmap is also the m-th _s
568 * (If you understood the previous sentence th
569 * read it, you're overqualified for your curr
570 *
571 * In other words, @orig is mapped onto (surje
572 * using the map { <n, m> | the n-th bit of @r
573 * m-th set bit of @relmap }.
574 *
575 * Any set bits in @orig above bit number W, w
576 * weight of (number of set bits in) @relmap a
577 * In particular, if for all bits m set in @or
578 * @dst will end up empty. In situations wher
579 * of such an empty result is not desired, one
580 * to use the bitmap_fold() operator, below, t
581 * @orig bitmap over itself so that all its se
582 * range 0 <= x < W. The bitmap_fold() operat
583 * setting the bit (m % W) in @dst, for each b
584 *
585 * Example [1] for bitmap_onto():
586 * Let's say @relmap has bits 30-39 set, and
587 * 1, 3, 5, 7, 9 and 11 set. Then on return
588 * @dst will have bits 31, 33, 35, 37 and 39
589 *
590 * When bit 0 is set in @orig, it means turn
591 * @dst corresponding to whatever is the firs
592 * that is turned on in @relmap. Since bit 0
593 * above example, we leave off that bit (bit
594 *
595 * When bit 1 is set in @orig (as in the abov
596 * means turn on the bit in @dst correspondin
597 * is the second bit that is turned on in @re
598 * bit in @relmap that was turned on in the a
599 * bit 31, so we turned on bit 31 in @dst.
600 *
601 * Similarly, we turned on bits 33, 35, 37 an
602 * because they were the 4th, 6th, 8th and 10
603 * set in @relmap, and the 4th, 6th, 8th and
604 * @orig (i.e. bits 3, 5, 7 and 9) were also
605 *
606 * When bit 11 is set in @orig, it means turn
607 * @dst corresponding to whatever is the twel
608 * turned on in @relmap. In the above exampl
609 * only ten bits turned on in @relmap (30..39
610 * 11 was set in @orig had no affect on @dst.
611 *
612 * Example [2] for bitmap_fold() + bitmap_onto
613 * Let's say @relmap has these ten bits set::
614 *
615 * 40 41 42 43 45 48 53 61 74 95
616 *
617 * (for the curious, that's 40 plus the first
618 * Fibonacci sequence.)
619 *
620 * Further lets say we use the following code
621 * bitmap_fold() then bitmap_onto, as suggest
622 * avoid the possibility of an empty @dst res
623 *
624 * unsigned long *tmp; // a temporary
625 *
626 * bitmap_fold(tmp, orig, bitmap_weight(r
627 * bitmap_onto(dst, tmp, relmap, bits);
628 *
629 * Then this table shows what various values
630 * various @orig's. I list the zero-based po
631 * The tmp column shows the intermediate resu
632 * using bitmap_fold() to fold the @orig bitm
633 * (the weight of @relmap):
634 *
635 * =============== ============== =======
636 * @orig tmp @dst
637 * 0 0 40
638 * 1 1 41
639 * 9 9 95
640 * 10 0 40 [#f1
641 * 1 3 5 7 1 3 5 7 41 43 4
642 * 0 1 2 3 4 0 1 2 3 4 40 41 4
643 * 0 9 18 27 0 9 8 7 40 61 7
644 * 0 10 20 30 0 40
645 * 0 11 22 33 0 1 2 3 40 41 4
646 * 0 12 24 36 0 2 4 6 40 42 4
647 * 78 102 211 1 2 8 41 42 7
648 * =============== ============== =======
649 *
650 * .. [#f1]
651 *
652 * For these marked lines, if we hadn't fi
653 * into tmp, then the @dst result would ha
654 *
655 * If either of @orig or @relmap is empty (no
656 * will be returned empty.
657 *
658 * If (as explained above) the only set bits i
659 * m where m >= W, (where W is the weight of @
660 * once again be returned empty.
661 *
662 * All bits in @dst not set by the above rule
663 */
664 void bitmap_onto(unsigned long *dst, const uns
665 const unsigned long *r
666 {
667 unsigned int n, m; /* same meanin
668
669 if (dst == orig) /* following d
670 return;
671 bitmap_zero(dst, bits);
672
673 /*
674 * The following code is a more effici
675 * obvious, equivalent to the loop:
676 * for (m = 0; m < bitmap_weight(
677 * n = find_nth_bit(orig,
678 * if (test_bit(m, orig))
679 * set_bit(n, dst
680 * }
681 */
682
683 m = 0;
684 for_each_set_bit(n, relmap, bits) {
685 /* m == bitmap_pos_to_ord(relm
686 if (test_bit(m, orig))
687 set_bit(n, dst);
688 m++;
689 }
690 }
691
692 /**
693 * bitmap_fold - fold larger bitmap into small
694 * @dst: resulting smaller bitmap
695 * @orig: original larger bitmap
696 * @sz: specified size
697 * @nbits: number of bits in each of thes
698 *
699 * For each bit oldbit in @orig, set bit oldbi
700 * Clear all other bits in @dst. See further
701 * Example [2] for bitmap_onto() for why and h
702 */
703 void bitmap_fold(unsigned long *dst, const uns
704 unsigned int sz, unsig
705 {
706 unsigned int oldbit;
707
708 if (dst == orig) /* following d
709 return;
710 bitmap_zero(dst, nbits);
711
712 for_each_set_bit(oldbit, orig, nbits)
713 set_bit(oldbit % sz, dst);
714 }
715 #endif /* CONFIG_NUMA */
716
717 unsigned long *bitmap_alloc(unsigned int nbits
718 {
719 return kmalloc_array(BITS_TO_LONGS(nbi
720 flags);
721 }
722 EXPORT_SYMBOL(bitmap_alloc);
723
724 unsigned long *bitmap_zalloc(unsigned int nbit
725 {
726 return bitmap_alloc(nbits, flags | __G
727 }
728 EXPORT_SYMBOL(bitmap_zalloc);
729
730 unsigned long *bitmap_alloc_node(unsigned int
731 {
732 return kmalloc_array_node(BITS_TO_LONG
733 flags, node)
734 }
735 EXPORT_SYMBOL(bitmap_alloc_node);
736
737 unsigned long *bitmap_zalloc_node(unsigned int
738 {
739 return bitmap_alloc_node(nbits, flags
740 }
741 EXPORT_SYMBOL(bitmap_zalloc_node);
742
743 void bitmap_free(const unsigned long *bitmap)
744 {
745 kfree(bitmap);
746 }
747 EXPORT_SYMBOL(bitmap_free);
748
749 static void devm_bitmap_free(void *data)
750 {
751 unsigned long *bitmap = data;
752
753 bitmap_free(bitmap);
754 }
755
756 unsigned long *devm_bitmap_alloc(struct device
757 unsigned int
758 {
759 unsigned long *bitmap;
760 int ret;
761
762 bitmap = bitmap_alloc(nbits, flags);
763 if (!bitmap)
764 return NULL;
765
766 ret = devm_add_action_or_reset(dev, de
767 if (ret)
768 return NULL;
769
770 return bitmap;
771 }
772 EXPORT_SYMBOL_GPL(devm_bitmap_alloc);
773
774 unsigned long *devm_bitmap_zalloc(struct devic
775 unsigned int
776 {
777 return devm_bitmap_alloc(dev, nbits, f
778 }
779 EXPORT_SYMBOL_GPL(devm_bitmap_zalloc);
780
781 #if BITS_PER_LONG == 64
782 /**
783 * bitmap_from_arr32 - copy the contents of u3
784 * @bitmap: array of unsigned longs, the
785 * @buf: array of u32 (in host byte order
786 * @nbits: number of bits in @bitmap
787 */
788 void bitmap_from_arr32(unsigned long *bitmap,
789 {
790 unsigned int i, halfwords;
791
792 halfwords = DIV_ROUND_UP(nbits, 32);
793 for (i = 0; i < halfwords; i++) {
794 bitmap[i/2] = (unsigned long)
795 if (++i < halfwords)
796 bitmap[i/2] |= ((unsig
797 }
798
799 /* Clear tail bits in last word beyond
800 if (nbits % BITS_PER_LONG)
801 bitmap[(halfwords - 1) / 2] &=
802 }
803 EXPORT_SYMBOL(bitmap_from_arr32);
804
805 /**
806 * bitmap_to_arr32 - copy the contents of bitm
807 * @buf: array of u32 (in host byte order
808 * @bitmap: array of unsigned longs, the
809 * @nbits: number of bits in @bitmap
810 */
811 void bitmap_to_arr32(u32 *buf, const unsigned
812 {
813 unsigned int i, halfwords;
814
815 halfwords = DIV_ROUND_UP(nbits, 32);
816 for (i = 0; i < halfwords; i++) {
817 buf[i] = (u32) (bitmap[i/2] &
818 if (++i < halfwords)
819 buf[i] = (u32) (bitmap
820 }
821
822 /* Clear tail bits in last element of
823 if (nbits % BITS_PER_LONG)
824 buf[halfwords - 1] &= (u32) (U
825 }
826 EXPORT_SYMBOL(bitmap_to_arr32);
827 #endif
828
829 #if BITS_PER_LONG == 32
830 /**
831 * bitmap_from_arr64 - copy the contents of u6
832 * @bitmap: array of unsigned longs, the
833 * @buf: array of u64 (in host byte order
834 * @nbits: number of bits in @bitmap
835 */
836 void bitmap_from_arr64(unsigned long *bitmap,
837 {
838 int n;
839
840 for (n = nbits; n > 0; n -= 64) {
841 u64 val = *buf++;
842
843 *bitmap++ = val;
844 if (n > 32)
845 *bitmap++ = val >> 32;
846 }
847
848 /*
849 * Clear tail bits in the last word be
850 *
851 * Negative index is OK because here w
852 * to the last word of the bitmap, exc
853 * is tested implicitly.
854 */
855 if (nbits % BITS_PER_LONG)
856 bitmap[-1] &= BITMAP_LAST_WORD
857 }
858 EXPORT_SYMBOL(bitmap_from_arr64);
859
860 /**
861 * bitmap_to_arr64 - copy the contents of bitm
862 * @buf: array of u64 (in host byte order
863 * @bitmap: array of unsigned longs, the
864 * @nbits: number of bits in @bitmap
865 */
866 void bitmap_to_arr64(u64 *buf, const unsigned
867 {
868 const unsigned long *end = bitmap + BI
869
870 while (bitmap < end) {
871 *buf = *bitmap++;
872 if (bitmap < end)
873 *buf |= (u64)(*bitmap+
874 buf++;
875 }
876
877 /* Clear tail bits in the last element
878 if (nbits % 64)
879 buf[-1] &= GENMASK_ULL((nbits
880 }
881 EXPORT_SYMBOL(bitmap_to_arr64);
882 #endif
883
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