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40b0b3f8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * lib/bitmap.c | |
4 | * Helper functions for bitmap.h. | |
1da177e4 | 5 | */ |
c13656b9 | 6 | |
1da177e4 LT |
7 | #include <linux/bitmap.h> |
8 | #include <linux/bitops.h> | |
50af5ead | 9 | #include <linux/bug.h> |
c13656b9 | 10 | #include <linux/ctype.h> |
e829c2e4 | 11 | #include <linux/device.h> |
c13656b9 BG |
12 | #include <linux/errno.h> |
13 | #include <linux/export.h> | |
e52bc7c2 | 14 | #include <linux/kernel.h> |
ce1091d4 | 15 | #include <linux/mm.h> |
c42b65e3 | 16 | #include <linux/slab.h> |
e52bc7c2 | 17 | #include <linux/string.h> |
c13656b9 | 18 | #include <linux/thread_info.h> |
13d4ea09 | 19 | #include <linux/uaccess.h> |
5aaba363 SH |
20 | |
21 | #include <asm/page.h> | |
1da177e4 | 22 | |
e371c481 YN |
23 | #include "kstrtox.h" |
24 | ||
7d7363e4 RD |
25 | /** |
26 | * DOC: bitmap introduction | |
27 | * | |
197d6c1d | 28 | * bitmaps provide an array of bits, implemented using an |
1da177e4 LT |
29 | * array of unsigned longs. The number of valid bits in a |
30 | * given bitmap does _not_ need to be an exact multiple of | |
31 | * BITS_PER_LONG. | |
32 | * | |
33 | * The possible unused bits in the last, partially used word | |
34 | * of a bitmap are 'don't care'. The implementation makes | |
35 | * no particular effort to keep them zero. It ensures that | |
36 | * their value will not affect the results of any operation. | |
37 | * The bitmap operations that return Boolean (bitmap_empty, | |
38 | * for example) or scalar (bitmap_weight, for example) results | |
39 | * carefully filter out these unused bits from impacting their | |
40 | * results. | |
41 | * | |
1da177e4 LT |
42 | * The byte ordering of bitmaps is more natural on little |
43 | * endian architectures. See the big-endian headers | |
44 | * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h | |
45 | * for the best explanations of this ordering. | |
46 | */ | |
47 | ||
1da177e4 | 48 | int __bitmap_equal(const unsigned long *bitmap1, |
5e068069 | 49 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 50 | { |
5e068069 | 51 | unsigned int k, lim = bits/BITS_PER_LONG; |
1da177e4 LT |
52 | for (k = 0; k < lim; ++k) |
53 | if (bitmap1[k] != bitmap2[k]) | |
54 | return 0; | |
55 | ||
56 | if (bits % BITS_PER_LONG) | |
57 | if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) | |
58 | return 0; | |
59 | ||
60 | return 1; | |
61 | } | |
62 | EXPORT_SYMBOL(__bitmap_equal); | |
63 | ||
b9fa6442 TG |
64 | bool __bitmap_or_equal(const unsigned long *bitmap1, |
65 | const unsigned long *bitmap2, | |
66 | const unsigned long *bitmap3, | |
67 | unsigned int bits) | |
68 | { | |
69 | unsigned int k, lim = bits / BITS_PER_LONG; | |
70 | unsigned long tmp; | |
71 | ||
72 | for (k = 0; k < lim; ++k) { | |
73 | if ((bitmap1[k] | bitmap2[k]) != bitmap3[k]) | |
74 | return false; | |
75 | } | |
76 | ||
77 | if (!(bits % BITS_PER_LONG)) | |
78 | return true; | |
79 | ||
80 | tmp = (bitmap1[k] | bitmap2[k]) ^ bitmap3[k]; | |
81 | return (tmp & BITMAP_LAST_WORD_MASK(bits)) == 0; | |
82 | } | |
83 | ||
3d6684f4 | 84 | void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits) |
1da177e4 | 85 | { |
ca1250bb | 86 | unsigned int k, lim = BITS_TO_LONGS(bits); |
1da177e4 LT |
87 | for (k = 0; k < lim; ++k) |
88 | dst[k] = ~src[k]; | |
1da177e4 LT |
89 | } |
90 | EXPORT_SYMBOL(__bitmap_complement); | |
91 | ||
72fd4a35 | 92 | /** |
1da177e4 | 93 | * __bitmap_shift_right - logical right shift of the bits in a bitmap |
05fb6bf0 RD |
94 | * @dst : destination bitmap |
95 | * @src : source bitmap | |
96 | * @shift : shift by this many bits | |
2fbad299 | 97 | * @nbits : bitmap size, in bits |
1da177e4 LT |
98 | * |
99 | * Shifting right (dividing) means moving bits in the MS -> LS bit | |
100 | * direction. Zeros are fed into the vacated MS positions and the | |
101 | * LS bits shifted off the bottom are lost. | |
102 | */ | |
2fbad299 RV |
103 | void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
104 | unsigned shift, unsigned nbits) | |
1da177e4 | 105 | { |
cfac1d08 | 106 | unsigned k, lim = BITS_TO_LONGS(nbits); |
2fbad299 | 107 | unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
cfac1d08 | 108 | unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); |
1da177e4 LT |
109 | for (k = 0; off + k < lim; ++k) { |
110 | unsigned long upper, lower; | |
111 | ||
112 | /* | |
113 | * If shift is not word aligned, take lower rem bits of | |
114 | * word above and make them the top rem bits of result. | |
115 | */ | |
116 | if (!rem || off + k + 1 >= lim) | |
117 | upper = 0; | |
118 | else { | |
119 | upper = src[off + k + 1]; | |
cfac1d08 | 120 | if (off + k + 1 == lim - 1) |
1da177e4 | 121 | upper &= mask; |
9d8a6b2a | 122 | upper <<= (BITS_PER_LONG - rem); |
1da177e4 LT |
123 | } |
124 | lower = src[off + k]; | |
cfac1d08 | 125 | if (off + k == lim - 1) |
1da177e4 | 126 | lower &= mask; |
9d8a6b2a RV |
127 | lower >>= rem; |
128 | dst[k] = lower | upper; | |
1da177e4 LT |
129 | } |
130 | if (off) | |
131 | memset(&dst[lim - off], 0, off*sizeof(unsigned long)); | |
132 | } | |
133 | EXPORT_SYMBOL(__bitmap_shift_right); | |
134 | ||
135 | ||
72fd4a35 | 136 | /** |
1da177e4 | 137 | * __bitmap_shift_left - logical left shift of the bits in a bitmap |
05fb6bf0 RD |
138 | * @dst : destination bitmap |
139 | * @src : source bitmap | |
140 | * @shift : shift by this many bits | |
dba94c25 | 141 | * @nbits : bitmap size, in bits |
1da177e4 LT |
142 | * |
143 | * Shifting left (multiplying) means moving bits in the LS -> MS | |
144 | * direction. Zeros are fed into the vacated LS bit positions | |
145 | * and those MS bits shifted off the top are lost. | |
146 | */ | |
147 | ||
dba94c25 RV |
148 | void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
149 | unsigned int shift, unsigned int nbits) | |
1da177e4 | 150 | { |
dba94c25 | 151 | int k; |
7f590657 | 152 | unsigned int lim = BITS_TO_LONGS(nbits); |
dba94c25 | 153 | unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
1da177e4 LT |
154 | for (k = lim - off - 1; k >= 0; --k) { |
155 | unsigned long upper, lower; | |
156 | ||
157 | /* | |
158 | * If shift is not word aligned, take upper rem bits of | |
159 | * word below and make them the bottom rem bits of result. | |
160 | */ | |
161 | if (rem && k > 0) | |
6d874eca | 162 | lower = src[k - 1] >> (BITS_PER_LONG - rem); |
1da177e4 LT |
163 | else |
164 | lower = 0; | |
7f590657 | 165 | upper = src[k] << rem; |
6d874eca | 166 | dst[k + off] = lower | upper; |
1da177e4 LT |
167 | } |
168 | if (off) | |
169 | memset(dst, 0, off*sizeof(unsigned long)); | |
170 | } | |
171 | EXPORT_SYMBOL(__bitmap_shift_left); | |
172 | ||
20927671 SB |
173 | /** |
174 | * bitmap_cut() - remove bit region from bitmap and right shift remaining bits | |
175 | * @dst: destination bitmap, might overlap with src | |
176 | * @src: source bitmap | |
177 | * @first: start bit of region to be removed | |
178 | * @cut: number of bits to remove | |
179 | * @nbits: bitmap size, in bits | |
180 | * | |
181 | * Set the n-th bit of @dst iff the n-th bit of @src is set and | |
182 | * n is less than @first, or the m-th bit of @src is set for any | |
183 | * m such that @first <= n < nbits, and m = n + @cut. | |
184 | * | |
185 | * In pictures, example for a big-endian 32-bit architecture: | |
186 | * | |
4642289b | 187 | * The @src bitmap is:: |
20927671 | 188 | * |
4642289b MCC |
189 | * 31 63 |
190 | * | | | |
191 | * 10000000 11000001 11110010 00010101 10000000 11000001 01110010 00010101 | |
192 | * | | | | | |
193 | * 16 14 0 32 | |
20927671 | 194 | * |
4642289b MCC |
195 | * if @cut is 3, and @first is 14, bits 14-16 in @src are cut and @dst is:: |
196 | * | |
197 | * 31 63 | |
198 | * | | | |
199 | * 10110000 00011000 00110010 00010101 00010000 00011000 00101110 01000010 | |
200 | * | | | | |
201 | * 14 (bit 17 0 32 | |
202 | * from @src) | |
20927671 SB |
203 | * |
204 | * Note that @dst and @src might overlap partially or entirely. | |
205 | * | |
206 | * This is implemented in the obvious way, with a shift and carry | |
207 | * step for each moved bit. Optimisation is left as an exercise | |
208 | * for the compiler. | |
209 | */ | |
210 | void bitmap_cut(unsigned long *dst, const unsigned long *src, | |
211 | unsigned int first, unsigned int cut, unsigned int nbits) | |
212 | { | |
213 | unsigned int len = BITS_TO_LONGS(nbits); | |
214 | unsigned long keep = 0, carry; | |
215 | int i; | |
216 | ||
20927671 SB |
217 | if (first % BITS_PER_LONG) { |
218 | keep = src[first / BITS_PER_LONG] & | |
219 | (~0UL >> (BITS_PER_LONG - first % BITS_PER_LONG)); | |
220 | } | |
221 | ||
5959f829 SB |
222 | memmove(dst, src, len * sizeof(*dst)); |
223 | ||
20927671 SB |
224 | while (cut--) { |
225 | for (i = first / BITS_PER_LONG; i < len; i++) { | |
226 | if (i < len - 1) | |
227 | carry = dst[i + 1] & 1UL; | |
228 | else | |
229 | carry = 0; | |
230 | ||
231 | dst[i] = (dst[i] >> 1) | (carry << (BITS_PER_LONG - 1)); | |
232 | } | |
233 | } | |
234 | ||
235 | dst[first / BITS_PER_LONG] &= ~0UL << (first % BITS_PER_LONG); | |
236 | dst[first / BITS_PER_LONG] |= keep; | |
237 | } | |
238 | EXPORT_SYMBOL(bitmap_cut); | |
239 | ||
f4b0373b | 240 | int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 241 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 242 | { |
2f9305eb | 243 | unsigned int k; |
7e5f97d1 | 244 | unsigned int lim = bits/BITS_PER_LONG; |
f4b0373b | 245 | unsigned long result = 0; |
1da177e4 | 246 | |
7e5f97d1 | 247 | for (k = 0; k < lim; k++) |
f4b0373b | 248 | result |= (dst[k] = bitmap1[k] & bitmap2[k]); |
7e5f97d1 RV |
249 | if (bits % BITS_PER_LONG) |
250 | result |= (dst[k] = bitmap1[k] & bitmap2[k] & | |
251 | BITMAP_LAST_WORD_MASK(bits)); | |
f4b0373b | 252 | return result != 0; |
1da177e4 LT |
253 | } |
254 | EXPORT_SYMBOL(__bitmap_and); | |
255 | ||
256 | void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, | |
2f9305eb | 257 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 258 | { |
2f9305eb RV |
259 | unsigned int k; |
260 | unsigned int nr = BITS_TO_LONGS(bits); | |
1da177e4 LT |
261 | |
262 | for (k = 0; k < nr; k++) | |
263 | dst[k] = bitmap1[k] | bitmap2[k]; | |
264 | } | |
265 | EXPORT_SYMBOL(__bitmap_or); | |
266 | ||
267 | void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, | |
2f9305eb | 268 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 269 | { |
2f9305eb RV |
270 | unsigned int k; |
271 | unsigned int nr = BITS_TO_LONGS(bits); | |
1da177e4 LT |
272 | |
273 | for (k = 0; k < nr; k++) | |
274 | dst[k] = bitmap1[k] ^ bitmap2[k]; | |
275 | } | |
276 | EXPORT_SYMBOL(__bitmap_xor); | |
277 | ||
f4b0373b | 278 | int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 279 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 280 | { |
2f9305eb | 281 | unsigned int k; |
74e76531 | 282 | unsigned int lim = bits/BITS_PER_LONG; |
f4b0373b | 283 | unsigned long result = 0; |
1da177e4 | 284 | |
74e76531 | 285 | for (k = 0; k < lim; k++) |
f4b0373b | 286 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k]); |
74e76531 RV |
287 | if (bits % BITS_PER_LONG) |
288 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k] & | |
289 | BITMAP_LAST_WORD_MASK(bits)); | |
f4b0373b | 290 | return result != 0; |
1da177e4 LT |
291 | } |
292 | EXPORT_SYMBOL(__bitmap_andnot); | |
293 | ||
30544ed5 AS |
294 | void __bitmap_replace(unsigned long *dst, |
295 | const unsigned long *old, const unsigned long *new, | |
296 | const unsigned long *mask, unsigned int nbits) | |
297 | { | |
298 | unsigned int k; | |
299 | unsigned int nr = BITS_TO_LONGS(nbits); | |
300 | ||
301 | for (k = 0; k < nr; k++) | |
302 | dst[k] = (old[k] & ~mask[k]) | (new[k] & mask[k]); | |
303 | } | |
304 | EXPORT_SYMBOL(__bitmap_replace); | |
305 | ||
1da177e4 | 306 | int __bitmap_intersects(const unsigned long *bitmap1, |
6dfe9799 | 307 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 308 | { |
6dfe9799 | 309 | unsigned int k, lim = bits/BITS_PER_LONG; |
1da177e4 LT |
310 | for (k = 0; k < lim; ++k) |
311 | if (bitmap1[k] & bitmap2[k]) | |
312 | return 1; | |
313 | ||
314 | if (bits % BITS_PER_LONG) | |
315 | if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) | |
316 | return 1; | |
317 | return 0; | |
318 | } | |
319 | EXPORT_SYMBOL(__bitmap_intersects); | |
320 | ||
321 | int __bitmap_subset(const unsigned long *bitmap1, | |
5be20213 | 322 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 323 | { |
5be20213 | 324 | unsigned int k, lim = bits/BITS_PER_LONG; |
1da177e4 LT |
325 | for (k = 0; k < lim; ++k) |
326 | if (bitmap1[k] & ~bitmap2[k]) | |
327 | return 0; | |
328 | ||
329 | if (bits % BITS_PER_LONG) | |
330 | if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) | |
331 | return 0; | |
332 | return 1; | |
333 | } | |
334 | EXPORT_SYMBOL(__bitmap_subset); | |
335 | ||
877d9f3b | 336 | int __bitmap_weight(const unsigned long *bitmap, unsigned int bits) |
1da177e4 | 337 | { |
877d9f3b RV |
338 | unsigned int k, lim = bits/BITS_PER_LONG; |
339 | int w = 0; | |
1da177e4 LT |
340 | |
341 | for (k = 0; k < lim; k++) | |
37d54111 | 342 | w += hweight_long(bitmap[k]); |
1da177e4 LT |
343 | |
344 | if (bits % BITS_PER_LONG) | |
37d54111 | 345 | w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits)); |
1da177e4 LT |
346 | |
347 | return w; | |
348 | } | |
1da177e4 LT |
349 | EXPORT_SYMBOL(__bitmap_weight); |
350 | ||
e5af323c | 351 | void __bitmap_set(unsigned long *map, unsigned int start, int len) |
c1a2a962 AM |
352 | { |
353 | unsigned long *p = map + BIT_WORD(start); | |
fb5ac542 | 354 | const unsigned int size = start + len; |
c1a2a962 AM |
355 | int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); |
356 | unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); | |
357 | ||
fb5ac542 | 358 | while (len - bits_to_set >= 0) { |
c1a2a962 | 359 | *p |= mask_to_set; |
fb5ac542 | 360 | len -= bits_to_set; |
c1a2a962 AM |
361 | bits_to_set = BITS_PER_LONG; |
362 | mask_to_set = ~0UL; | |
363 | p++; | |
364 | } | |
fb5ac542 | 365 | if (len) { |
c1a2a962 AM |
366 | mask_to_set &= BITMAP_LAST_WORD_MASK(size); |
367 | *p |= mask_to_set; | |
368 | } | |
369 | } | |
e5af323c | 370 | EXPORT_SYMBOL(__bitmap_set); |
c1a2a962 | 371 | |
e5af323c | 372 | void __bitmap_clear(unsigned long *map, unsigned int start, int len) |
c1a2a962 AM |
373 | { |
374 | unsigned long *p = map + BIT_WORD(start); | |
154f5e38 | 375 | const unsigned int size = start + len; |
c1a2a962 AM |
376 | int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); |
377 | unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); | |
378 | ||
154f5e38 | 379 | while (len - bits_to_clear >= 0) { |
c1a2a962 | 380 | *p &= ~mask_to_clear; |
154f5e38 | 381 | len -= bits_to_clear; |
c1a2a962 AM |
382 | bits_to_clear = BITS_PER_LONG; |
383 | mask_to_clear = ~0UL; | |
384 | p++; | |
385 | } | |
154f5e38 | 386 | if (len) { |
c1a2a962 AM |
387 | mask_to_clear &= BITMAP_LAST_WORD_MASK(size); |
388 | *p &= ~mask_to_clear; | |
389 | } | |
390 | } | |
e5af323c | 391 | EXPORT_SYMBOL(__bitmap_clear); |
c1a2a962 | 392 | |
5e19b013 MN |
393 | /** |
394 | * bitmap_find_next_zero_area_off - find a contiguous aligned zero area | |
c1a2a962 AM |
395 | * @map: The address to base the search on |
396 | * @size: The bitmap size in bits | |
397 | * @start: The bitnumber to start searching at | |
398 | * @nr: The number of zeroed bits we're looking for | |
399 | * @align_mask: Alignment mask for zero area | |
5e19b013 | 400 | * @align_offset: Alignment offset for zero area. |
c1a2a962 AM |
401 | * |
402 | * The @align_mask should be one less than a power of 2; the effect is that | |
5e19b013 MN |
403 | * the bit offset of all zero areas this function finds plus @align_offset |
404 | * is multiple of that power of 2. | |
c1a2a962 | 405 | */ |
5e19b013 MN |
406 | unsigned long bitmap_find_next_zero_area_off(unsigned long *map, |
407 | unsigned long size, | |
408 | unsigned long start, | |
409 | unsigned int nr, | |
410 | unsigned long align_mask, | |
411 | unsigned long align_offset) | |
c1a2a962 AM |
412 | { |
413 | unsigned long index, end, i; | |
414 | again: | |
415 | index = find_next_zero_bit(map, size, start); | |
416 | ||
417 | /* Align allocation */ | |
5e19b013 | 418 | index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset; |
c1a2a962 AM |
419 | |
420 | end = index + nr; | |
421 | if (end > size) | |
422 | return end; | |
423 | i = find_next_bit(map, end, index); | |
424 | if (i < end) { | |
425 | start = i + 1; | |
426 | goto again; | |
427 | } | |
428 | return index; | |
429 | } | |
5e19b013 | 430 | EXPORT_SYMBOL(bitmap_find_next_zero_area_off); |
c1a2a962 | 431 | |
1da177e4 | 432 | /* |
6d49e352 | 433 | * Bitmap printing & parsing functions: first version by Nadia Yvette Chambers, |
1da177e4 LT |
434 | * second version by Paul Jackson, third by Joe Korty. |
435 | */ | |
436 | ||
01a3ee2b | 437 | /** |
9a86e2ba | 438 | * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap |
01a3ee2b RC |
439 | * |
440 | * @ubuf: pointer to user buffer containing string. | |
441 | * @ulen: buffer size in bytes. If string is smaller than this | |
442 | * then it must be terminated with a \0. | |
443 | * @maskp: pointer to bitmap array that will contain result. | |
444 | * @nmaskbits: size of bitmap, in bits. | |
01a3ee2b RC |
445 | */ |
446 | int bitmap_parse_user(const char __user *ubuf, | |
447 | unsigned int ulen, unsigned long *maskp, | |
448 | int nmaskbits) | |
449 | { | |
e66eda06 YN |
450 | char *buf; |
451 | int ret; | |
452 | ||
453 | buf = memdup_user_nul(ubuf, ulen); | |
454 | if (IS_ERR(buf)) | |
455 | return PTR_ERR(buf); | |
456 | ||
2d626158 | 457 | ret = bitmap_parse(buf, UINT_MAX, maskp, nmaskbits); |
b9c321fd | 458 | |
e66eda06 YN |
459 | kfree(buf); |
460 | return ret; | |
01a3ee2b RC |
461 | } |
462 | EXPORT_SYMBOL(bitmap_parse_user); | |
1da177e4 | 463 | |
5aaba363 SH |
464 | /** |
465 | * bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string | |
466 | * @list: indicates whether the bitmap must be list | |
467 | * @buf: page aligned buffer into which string is placed | |
468 | * @maskp: pointer to bitmap to convert | |
469 | * @nmaskbits: size of bitmap, in bits | |
470 | * | |
471 | * Output format is a comma-separated list of decimal numbers and | |
472 | * ranges if list is specified or hex digits grouped into comma-separated | |
473 | * sets of 8 digits/set. Returns the number of characters written to buf. | |
9cf79d11 | 474 | * |
ce1091d4 RV |
475 | * It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned |
476 | * area and that sufficient storage remains at @buf to accommodate the | |
477 | * bitmap_print_to_pagebuf() output. Returns the number of characters | |
478 | * actually printed to @buf, excluding terminating '\0'. | |
5aaba363 SH |
479 | */ |
480 | int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, | |
481 | int nmaskbits) | |
482 | { | |
ce1091d4 | 483 | ptrdiff_t len = PAGE_SIZE - offset_in_page(buf); |
5aaba363 | 484 | |
8ec3d768 RV |
485 | return list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) : |
486 | scnprintf(buf, len, "%*pb\n", nmaskbits, maskp); | |
5aaba363 SH |
487 | } |
488 | EXPORT_SYMBOL(bitmap_print_to_pagebuf); | |
489 | ||
1fae5629 TT |
490 | /** |
491 | * bitmap_print_to_buf - convert bitmap to list or hex format ASCII string | |
492 | * @list: indicates whether the bitmap must be list | |
493 | * true: print in decimal list format | |
494 | * false: print in hexadecimal bitmask format | |
495 | */ | |
496 | static int bitmap_print_to_buf(bool list, char *buf, const unsigned long *maskp, | |
497 | int nmaskbits, loff_t off, size_t count) | |
498 | { | |
499 | const char *fmt = list ? "%*pbl\n" : "%*pb\n"; | |
500 | ssize_t size; | |
501 | void *data; | |
502 | ||
503 | data = kasprintf(GFP_KERNEL, fmt, nmaskbits, maskp); | |
504 | if (!data) | |
505 | return -ENOMEM; | |
506 | ||
507 | size = memory_read_from_buffer(buf, count, &off, data, strlen(data) + 1); | |
508 | kfree(data); | |
509 | ||
510 | return size; | |
511 | } | |
512 | ||
513 | /** | |
514 | * bitmap_print_bitmask_to_buf - convert bitmap to hex bitmask format ASCII string | |
515 | * | |
516 | * The bitmap_print_to_pagebuf() is used indirectly via its cpumap wrapper | |
517 | * cpumap_print_to_pagebuf() or directly by drivers to export hexadecimal | |
518 | * bitmask and decimal list to userspace by sysfs ABI. | |
519 | * Drivers might be using a normal attribute for this kind of ABIs. A | |
520 | * normal attribute typically has show entry as below: | |
521 | * static ssize_t example_attribute_show(struct device *dev, | |
522 | * struct device_attribute *attr, char *buf) | |
523 | * { | |
524 | * ... | |
525 | * return bitmap_print_to_pagebuf(true, buf, &mask, nr_trig_max); | |
526 | * } | |
527 | * show entry of attribute has no offset and count parameters and this | |
528 | * means the file is limited to one page only. | |
529 | * bitmap_print_to_pagebuf() API works terribly well for this kind of | |
530 | * normal attribute with buf parameter and without offset, count: | |
531 | * bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, | |
532 | * int nmaskbits) | |
533 | * { | |
534 | * } | |
535 | * The problem is once we have a large bitmap, we have a chance to get a | |
536 | * bitmask or list more than one page. Especially for list, it could be | |
537 | * as complex as 0,3,5,7,9,... We have no simple way to know it exact size. | |
538 | * It turns out bin_attribute is a way to break this limit. bin_attribute | |
539 | * has show entry as below: | |
540 | * static ssize_t | |
541 | * example_bin_attribute_show(struct file *filp, struct kobject *kobj, | |
542 | * struct bin_attribute *attr, char *buf, | |
543 | * loff_t offset, size_t count) | |
544 | * { | |
545 | * ... | |
546 | * } | |
547 | * With the new offset and count parameters, this makes sysfs ABI be able | |
548 | * to support file size more than one page. For example, offset could be | |
549 | * >= 4096. | |
550 | * bitmap_print_bitmask_to_buf(), bitmap_print_list_to_buf() wit their | |
551 | * cpumap wrapper cpumap_print_bitmask_to_buf(), cpumap_print_list_to_buf() | |
552 | * make those drivers be able to support large bitmask and list after they | |
553 | * move to use bin_attribute. In result, we have to pass the corresponding | |
554 | * parameters such as off, count from bin_attribute show entry to this API. | |
555 | * | |
556 | * @buf: buffer into which string is placed | |
557 | * @maskp: pointer to bitmap to convert | |
558 | * @nmaskbits: size of bitmap, in bits | |
559 | * @off: in the string from which we are copying, We copy to @buf | |
560 | * @count: the maximum number of bytes to print | |
561 | * | |
562 | * The role of cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf() | |
563 | * is similar with cpumap_print_to_pagebuf(), the difference is that | |
564 | * bitmap_print_to_pagebuf() mainly serves sysfs attribute with the assumption | |
565 | * the destination buffer is exactly one page and won't be more than one page. | |
566 | * cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf(), on the other | |
567 | * hand, mainly serves bin_attribute which doesn't work with exact one page, | |
568 | * and it can break the size limit of converted decimal list and hexadecimal | |
569 | * bitmask. | |
570 | * | |
3b35f2a6 YN |
571 | * WARNING! |
572 | * | |
573 | * This function is not a replacement for sprintf() or bitmap_print_to_pagebuf(). | |
574 | * It is intended to workaround sysfs limitations discussed above and should be | |
575 | * used carefully in general case for the following reasons: | |
576 | * - Time complexity is O(nbits^2/count), comparing to O(nbits) for snprintf(). | |
577 | * - Memory complexity is O(nbits), comparing to O(1) for snprintf(). | |
578 | * - @off and @count are NOT offset and number of bits to print. | |
579 | * - If printing part of bitmap as list, the resulting string is not a correct | |
580 | * list representation of bitmap. Particularly, some bits within or out of | |
581 | * related interval may be erroneously set or unset. The format of the string | |
582 | * may be broken, so bitmap_parselist-like parser may fail parsing it. | |
583 | * - If printing the whole bitmap as list by parts, user must ensure the order | |
584 | * of calls of the function such that the offset is incremented linearly. | |
585 | * - If printing the whole bitmap as list by parts, user must keep bitmap | |
586 | * unchanged between the very first and very last call. Otherwise concatenated | |
587 | * result may be incorrect, and format may be broken. | |
588 | * | |
1fae5629 TT |
589 | * Returns the number of characters actually printed to @buf |
590 | */ | |
591 | int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp, | |
592 | int nmaskbits, loff_t off, size_t count) | |
593 | { | |
594 | return bitmap_print_to_buf(false, buf, maskp, nmaskbits, off, count); | |
595 | } | |
596 | EXPORT_SYMBOL(bitmap_print_bitmask_to_buf); | |
597 | ||
598 | /** | |
599 | * bitmap_print_list_to_buf - convert bitmap to decimal list format ASCII string | |
600 | * | |
601 | * Everything is same with the above bitmap_print_bitmask_to_buf() except | |
602 | * the print format. | |
603 | */ | |
604 | int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp, | |
605 | int nmaskbits, loff_t off, size_t count) | |
606 | { | |
607 | return bitmap_print_to_buf(true, buf, maskp, nmaskbits, off, count); | |
608 | } | |
609 | EXPORT_SYMBOL(bitmap_print_list_to_buf); | |
610 | ||
e371c481 YN |
611 | /* |
612 | * Region 9-38:4/10 describes the following bitmap structure: | |
9d7a3366 PG |
613 | * 0 9 12 18 38 N |
614 | * .........****......****......****.................. | |
615 | * ^ ^ ^ ^ ^ | |
616 | * start off group_len end nbits | |
e371c481 YN |
617 | */ |
618 | struct region { | |
619 | unsigned int start; | |
620 | unsigned int off; | |
621 | unsigned int group_len; | |
622 | unsigned int end; | |
9d7a3366 | 623 | unsigned int nbits; |
e371c481 YN |
624 | }; |
625 | ||
f3c869ca | 626 | static void bitmap_set_region(const struct region *r, unsigned long *bitmap) |
e371c481 YN |
627 | { |
628 | unsigned int start; | |
629 | ||
e371c481 YN |
630 | for (start = r->start; start <= r->end; start += r->group_len) |
631 | bitmap_set(bitmap, start, min(r->end - start + 1, r->off)); | |
e371c481 YN |
632 | } |
633 | ||
634 | static int bitmap_check_region(const struct region *r) | |
635 | { | |
636 | if (r->start > r->end || r->group_len == 0 || r->off > r->group_len) | |
637 | return -EINVAL; | |
638 | ||
f3c869ca PG |
639 | if (r->end >= r->nbits) |
640 | return -ERANGE; | |
641 | ||
e371c481 YN |
642 | return 0; |
643 | } | |
644 | ||
2c4885d2 PG |
645 | static const char *bitmap_getnum(const char *str, unsigned int *num, |
646 | unsigned int lastbit) | |
e371c481 YN |
647 | { |
648 | unsigned long long n; | |
649 | unsigned int len; | |
650 | ||
2c4885d2 PG |
651 | if (str[0] == 'N') { |
652 | *num = lastbit; | |
653 | return str + 1; | |
654 | } | |
655 | ||
e371c481 YN |
656 | len = _parse_integer(str, 10, &n); |
657 | if (!len) | |
658 | return ERR_PTR(-EINVAL); | |
659 | if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n) | |
660 | return ERR_PTR(-EOVERFLOW); | |
661 | ||
662 | *num = n; | |
663 | return str + len; | |
664 | } | |
665 | ||
666 | static inline bool end_of_str(char c) | |
667 | { | |
668 | return c == '\0' || c == '\n'; | |
669 | } | |
670 | ||
671 | static inline bool __end_of_region(char c) | |
672 | { | |
673 | return isspace(c) || c == ','; | |
674 | } | |
675 | ||
676 | static inline bool end_of_region(char c) | |
677 | { | |
678 | return __end_of_region(c) || end_of_str(c); | |
679 | } | |
680 | ||
681 | /* | |
20607434 | 682 | * The format allows commas and whitespaces at the beginning |
e371c481 YN |
683 | * of the region. |
684 | */ | |
685 | static const char *bitmap_find_region(const char *str) | |
686 | { | |
687 | while (__end_of_region(*str)) | |
688 | str++; | |
689 | ||
690 | return end_of_str(*str) ? NULL : str; | |
691 | } | |
692 | ||
2d626158 YN |
693 | static const char *bitmap_find_region_reverse(const char *start, const char *end) |
694 | { | |
695 | while (start <= end && __end_of_region(*end)) | |
696 | end--; | |
697 | ||
698 | return end; | |
699 | } | |
700 | ||
e371c481 YN |
701 | static const char *bitmap_parse_region(const char *str, struct region *r) |
702 | { | |
2c4885d2 PG |
703 | unsigned int lastbit = r->nbits - 1; |
704 | ||
b18def12 YN |
705 | if (!strncasecmp(str, "all", 3)) { |
706 | r->start = 0; | |
707 | r->end = lastbit; | |
708 | str += 3; | |
709 | ||
710 | goto check_pattern; | |
711 | } | |
712 | ||
2c4885d2 | 713 | str = bitmap_getnum(str, &r->start, lastbit); |
e371c481 YN |
714 | if (IS_ERR(str)) |
715 | return str; | |
716 | ||
717 | if (end_of_region(*str)) | |
718 | goto no_end; | |
719 | ||
720 | if (*str != '-') | |
721 | return ERR_PTR(-EINVAL); | |
722 | ||
2c4885d2 | 723 | str = bitmap_getnum(str + 1, &r->end, lastbit); |
e371c481 YN |
724 | if (IS_ERR(str)) |
725 | return str; | |
726 | ||
b18def12 | 727 | check_pattern: |
e371c481 YN |
728 | if (end_of_region(*str)) |
729 | goto no_pattern; | |
730 | ||
731 | if (*str != ':') | |
732 | return ERR_PTR(-EINVAL); | |
733 | ||
2c4885d2 | 734 | str = bitmap_getnum(str + 1, &r->off, lastbit); |
e371c481 YN |
735 | if (IS_ERR(str)) |
736 | return str; | |
737 | ||
738 | if (*str != '/') | |
739 | return ERR_PTR(-EINVAL); | |
740 | ||
2c4885d2 | 741 | return bitmap_getnum(str + 1, &r->group_len, lastbit); |
e371c481 YN |
742 | |
743 | no_end: | |
744 | r->end = r->start; | |
745 | no_pattern: | |
746 | r->off = r->end + 1; | |
747 | r->group_len = r->end + 1; | |
748 | ||
749 | return end_of_str(*str) ? NULL : str; | |
750 | } | |
751 | ||
1da177e4 | 752 | /** |
e371c481 YN |
753 | * bitmap_parselist - convert list format ASCII string to bitmap |
754 | * @buf: read user string from this buffer; must be terminated | |
755 | * with a \0 or \n. | |
6e1907ff | 756 | * @maskp: write resulting mask here |
1da177e4 LT |
757 | * @nmaskbits: number of bits in mask to be written |
758 | * | |
759 | * Input format is a comma-separated list of decimal numbers and | |
760 | * ranges. Consecutively set bits are shown as two hyphen-separated | |
761 | * decimal numbers, the smallest and largest bit numbers set in | |
762 | * the range. | |
2d13e6ca NC |
763 | * Optionally each range can be postfixed to denote that only parts of it |
764 | * should be set. The range will divided to groups of specific size. | |
765 | * From each group will be used only defined amount of bits. | |
766 | * Syntax: range:used_size/group_size | |
767 | * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 | |
2c4885d2 PG |
768 | * The value 'N' can be used as a dynamically substituted token for the |
769 | * maximum allowed value; i.e (nmaskbits - 1). Keep in mind that it is | |
770 | * dynamic, so if system changes cause the bitmap width to change, such | |
771 | * as more cores in a CPU list, then any ranges using N will also change. | |
1da177e4 | 772 | * |
40bf19a8 | 773 | * Returns: 0 on success, -errno on invalid input strings. Error values: |
774 | * | |
e371c481 | 775 | * - ``-EINVAL``: wrong region format |
40bf19a8 | 776 | * - ``-EINVAL``: invalid character in string |
777 | * - ``-ERANGE``: bit number specified too large for mask | |
e371c481 | 778 | * - ``-EOVERFLOW``: integer overflow in the input parameters |
1da177e4 | 779 | */ |
e371c481 | 780 | int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) |
1da177e4 | 781 | { |
e371c481 YN |
782 | struct region r; |
783 | long ret; | |
1da177e4 | 784 | |
9d7a3366 PG |
785 | r.nbits = nmaskbits; |
786 | bitmap_zero(maskp, r.nbits); | |
4b060420 | 787 | |
e371c481 YN |
788 | while (buf) { |
789 | buf = bitmap_find_region(buf); | |
790 | if (buf == NULL) | |
791 | return 0; | |
2d13e6ca | 792 | |
e371c481 YN |
793 | buf = bitmap_parse_region(buf, &r); |
794 | if (IS_ERR(buf)) | |
795 | return PTR_ERR(buf); | |
2d13e6ca | 796 | |
e371c481 YN |
797 | ret = bitmap_check_region(&r); |
798 | if (ret) | |
799 | return ret; | |
4b060420 | 800 | |
f3c869ca | 801 | bitmap_set_region(&r, maskp); |
e371c481 | 802 | } |
4b060420 | 803 | |
1da177e4 LT |
804 | return 0; |
805 | } | |
806 | EXPORT_SYMBOL(bitmap_parselist); | |
807 | ||
4b060420 MT |
808 | |
809 | /** | |
810 | * bitmap_parselist_user() | |
811 | * | |
812 | * @ubuf: pointer to user buffer containing string. | |
813 | * @ulen: buffer size in bytes. If string is smaller than this | |
814 | * then it must be terminated with a \0. | |
815 | * @maskp: pointer to bitmap array that will contain result. | |
816 | * @nmaskbits: size of bitmap, in bits. | |
817 | * | |
818 | * Wrapper for bitmap_parselist(), providing it with user buffer. | |
4b060420 MT |
819 | */ |
820 | int bitmap_parselist_user(const char __user *ubuf, | |
821 | unsigned int ulen, unsigned long *maskp, | |
822 | int nmaskbits) | |
823 | { | |
281327c9 YN |
824 | char *buf; |
825 | int ret; | |
826 | ||
827 | buf = memdup_user_nul(ubuf, ulen); | |
828 | if (IS_ERR(buf)) | |
829 | return PTR_ERR(buf); | |
830 | ||
831 | ret = bitmap_parselist(buf, maskp, nmaskbits); | |
832 | ||
833 | kfree(buf); | |
834 | return ret; | |
4b060420 MT |
835 | } |
836 | EXPORT_SYMBOL(bitmap_parselist_user); | |
837 | ||
2d626158 YN |
838 | static const char *bitmap_get_x32_reverse(const char *start, |
839 | const char *end, u32 *num) | |
840 | { | |
841 | u32 ret = 0; | |
842 | int c, i; | |
843 | ||
844 | for (i = 0; i < 32; i += 4) { | |
845 | c = hex_to_bin(*end--); | |
846 | if (c < 0) | |
847 | return ERR_PTR(-EINVAL); | |
848 | ||
849 | ret |= c << i; | |
850 | ||
851 | if (start > end || __end_of_region(*end)) | |
852 | goto out; | |
853 | } | |
854 | ||
855 | if (hex_to_bin(*end--) >= 0) | |
856 | return ERR_PTR(-EOVERFLOW); | |
857 | out: | |
858 | *num = ret; | |
859 | return end; | |
860 | } | |
861 | ||
862 | /** | |
863 | * bitmap_parse - convert an ASCII hex string into a bitmap. | |
864 | * @start: pointer to buffer containing string. | |
865 | * @buflen: buffer size in bytes. If string is smaller than this | |
866 | * then it must be terminated with a \0 or \n. In that case, | |
867 | * UINT_MAX may be provided instead of string length. | |
868 | * @maskp: pointer to bitmap array that will contain result. | |
869 | * @nmaskbits: size of bitmap, in bits. | |
870 | * | |
871 | * Commas group hex digits into chunks. Each chunk defines exactly 32 | |
872 | * bits of the resultant bitmask. No chunk may specify a value larger | |
873 | * than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value | |
874 | * then leading 0-bits are prepended. %-EINVAL is returned for illegal | |
875 | * characters. Grouping such as "1,,5", ",44", "," or "" is allowed. | |
876 | * Leading, embedded and trailing whitespace accepted. | |
877 | */ | |
878 | int bitmap_parse(const char *start, unsigned int buflen, | |
879 | unsigned long *maskp, int nmaskbits) | |
880 | { | |
881 | const char *end = strnchrnul(start, buflen, '\n') - 1; | |
882 | int chunks = BITS_TO_U32(nmaskbits); | |
883 | u32 *bitmap = (u32 *)maskp; | |
884 | int unset_bit; | |
81c4f4d9 | 885 | int chunk; |
2d626158 | 886 | |
81c4f4d9 | 887 | for (chunk = 0; ; chunk++) { |
2d626158 YN |
888 | end = bitmap_find_region_reverse(start, end); |
889 | if (start > end) | |
890 | break; | |
891 | ||
892 | if (!chunks--) | |
893 | return -EOVERFLOW; | |
894 | ||
81c4f4d9 AG |
895 | #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) |
896 | end = bitmap_get_x32_reverse(start, end, &bitmap[chunk ^ 1]); | |
897 | #else | |
898 | end = bitmap_get_x32_reverse(start, end, &bitmap[chunk]); | |
899 | #endif | |
2d626158 YN |
900 | if (IS_ERR(end)) |
901 | return PTR_ERR(end); | |
902 | } | |
903 | ||
904 | unset_bit = (BITS_TO_U32(nmaskbits) - chunks) * 32; | |
905 | if (unset_bit < nmaskbits) { | |
906 | bitmap_clear(maskp, unset_bit, nmaskbits - unset_bit); | |
907 | return 0; | |
908 | } | |
909 | ||
910 | if (find_next_bit(maskp, unset_bit, nmaskbits) != unset_bit) | |
911 | return -EOVERFLOW; | |
912 | ||
913 | return 0; | |
914 | } | |
915 | EXPORT_SYMBOL(bitmap_parse); | |
916 | ||
72fd4a35 | 917 | /** |
9a86e2ba | 918 | * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap |
fb5eeeee | 919 | * @buf: pointer to a bitmap |
df1d80a9 RV |
920 | * @pos: a bit position in @buf (0 <= @pos < @nbits) |
921 | * @nbits: number of valid bit positions in @buf | |
fb5eeeee | 922 | * |
df1d80a9 | 923 | * Map the bit at position @pos in @buf (of length @nbits) to the |
fb5eeeee | 924 | * ordinal of which set bit it is. If it is not set or if @pos |
96b7f341 | 925 | * is not a valid bit position, map to -1. |
fb5eeeee PJ |
926 | * |
927 | * If for example, just bits 4 through 7 are set in @buf, then @pos | |
928 | * values 4 through 7 will get mapped to 0 through 3, respectively, | |
a8551748 | 929 | * and other @pos values will get mapped to -1. When @pos value 7 |
fb5eeeee PJ |
930 | * gets mapped to (returns) @ord value 3 in this example, that means |
931 | * that bit 7 is the 3rd (starting with 0th) set bit in @buf. | |
932 | * | |
933 | * The bit positions 0 through @bits are valid positions in @buf. | |
934 | */ | |
df1d80a9 | 935 | static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits) |
fb5eeeee | 936 | { |
df1d80a9 | 937 | if (pos >= nbits || !test_bit(pos, buf)) |
96b7f341 | 938 | return -1; |
fb5eeeee | 939 | |
df1d80a9 | 940 | return __bitmap_weight(buf, pos); |
fb5eeeee PJ |
941 | } |
942 | ||
943 | /** | |
9a86e2ba | 944 | * bitmap_ord_to_pos - find position of n-th set bit in bitmap |
fb5eeeee PJ |
945 | * @buf: pointer to bitmap |
946 | * @ord: ordinal bit position (n-th set bit, n >= 0) | |
f6a1f5db | 947 | * @nbits: number of valid bit positions in @buf |
fb5eeeee PJ |
948 | * |
949 | * Map the ordinal offset of bit @ord in @buf to its position in @buf. | |
f6a1f5db RV |
950 | * Value of @ord should be in range 0 <= @ord < weight(buf). If @ord |
951 | * >= weight(buf), returns @nbits. | |
fb5eeeee PJ |
952 | * |
953 | * If for example, just bits 4 through 7 are set in @buf, then @ord | |
954 | * values 0 through 3 will get mapped to 4 through 7, respectively, | |
f6a1f5db | 955 | * and all other @ord values returns @nbits. When @ord value 3 |
fb5eeeee PJ |
956 | * gets mapped to (returns) @pos value 7 in this example, that means |
957 | * that the 3rd set bit (starting with 0th) is at position 7 in @buf. | |
958 | * | |
f6a1f5db | 959 | * The bit positions 0 through @nbits-1 are valid positions in @buf. |
fb5eeeee | 960 | */ |
f6a1f5db | 961 | unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits) |
fb5eeeee | 962 | { |
f6a1f5db | 963 | unsigned int pos; |
fb5eeeee | 964 | |
f6a1f5db RV |
965 | for (pos = find_first_bit(buf, nbits); |
966 | pos < nbits && ord; | |
967 | pos = find_next_bit(buf, nbits, pos + 1)) | |
968 | ord--; | |
fb5eeeee PJ |
969 | |
970 | return pos; | |
971 | } | |
972 | ||
973 | /** | |
974 | * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap | |
fb5eeeee | 975 | * @dst: remapped result |
96b7f341 | 976 | * @src: subset to be remapped |
fb5eeeee PJ |
977 | * @old: defines domain of map |
978 | * @new: defines range of map | |
9814ec13 | 979 | * @nbits: number of bits in each of these bitmaps |
fb5eeeee PJ |
980 | * |
981 | * Let @old and @new define a mapping of bit positions, such that | |
982 | * whatever position is held by the n-th set bit in @old is mapped | |
983 | * to the n-th set bit in @new. In the more general case, allowing | |
984 | * for the possibility that the weight 'w' of @new is less than the | |
985 | * weight of @old, map the position of the n-th set bit in @old to | |
986 | * the position of the m-th set bit in @new, where m == n % w. | |
987 | * | |
96b7f341 PJ |
988 | * If either of the @old and @new bitmaps are empty, or if @src and |
989 | * @dst point to the same location, then this routine copies @src | |
990 | * to @dst. | |
fb5eeeee | 991 | * |
96b7f341 PJ |
992 | * The positions of unset bits in @old are mapped to themselves |
993 | * (the identify map). | |
fb5eeeee PJ |
994 | * |
995 | * Apply the above specified mapping to @src, placing the result in | |
996 | * @dst, clearing any bits previously set in @dst. | |
997 | * | |
fb5eeeee PJ |
998 | * For example, lets say that @old has bits 4 through 7 set, and |
999 | * @new has bits 12 through 15 set. This defines the mapping of bit | |
1000 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other | |
96b7f341 PJ |
1001 | * bit positions unchanged. So if say @src comes into this routine |
1002 | * with bits 1, 5 and 7 set, then @dst should leave with bits 1, | |
1003 | * 13 and 15 set. | |
fb5eeeee PJ |
1004 | */ |
1005 | void bitmap_remap(unsigned long *dst, const unsigned long *src, | |
1006 | const unsigned long *old, const unsigned long *new, | |
9814ec13 | 1007 | unsigned int nbits) |
fb5eeeee | 1008 | { |
9814ec13 | 1009 | unsigned int oldbit, w; |
fb5eeeee | 1010 | |
fb5eeeee PJ |
1011 | if (dst == src) /* following doesn't handle inplace remaps */ |
1012 | return; | |
9814ec13 | 1013 | bitmap_zero(dst, nbits); |
96b7f341 | 1014 | |
9814ec13 RV |
1015 | w = bitmap_weight(new, nbits); |
1016 | for_each_set_bit(oldbit, src, nbits) { | |
1017 | int n = bitmap_pos_to_ord(old, oldbit, nbits); | |
08564fb7 | 1018 | |
96b7f341 PJ |
1019 | if (n < 0 || w == 0) |
1020 | set_bit(oldbit, dst); /* identity map */ | |
1021 | else | |
9814ec13 | 1022 | set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst); |
fb5eeeee PJ |
1023 | } |
1024 | } | |
cde3d0f8 | 1025 | EXPORT_SYMBOL(bitmap_remap); |
fb5eeeee PJ |
1026 | |
1027 | /** | |
1028 | * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit | |
6e1907ff RD |
1029 | * @oldbit: bit position to be mapped |
1030 | * @old: defines domain of map | |
1031 | * @new: defines range of map | |
1032 | * @bits: number of bits in each of these bitmaps | |
fb5eeeee PJ |
1033 | * |
1034 | * Let @old and @new define a mapping of bit positions, such that | |
1035 | * whatever position is held by the n-th set bit in @old is mapped | |
1036 | * to the n-th set bit in @new. In the more general case, allowing | |
1037 | * for the possibility that the weight 'w' of @new is less than the | |
1038 | * weight of @old, map the position of the n-th set bit in @old to | |
1039 | * the position of the m-th set bit in @new, where m == n % w. | |
1040 | * | |
96b7f341 PJ |
1041 | * The positions of unset bits in @old are mapped to themselves |
1042 | * (the identify map). | |
fb5eeeee PJ |
1043 | * |
1044 | * Apply the above specified mapping to bit position @oldbit, returning | |
1045 | * the new bit position. | |
1046 | * | |
1047 | * For example, lets say that @old has bits 4 through 7 set, and | |
1048 | * @new has bits 12 through 15 set. This defines the mapping of bit | |
1049 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other | |
96b7f341 PJ |
1050 | * bit positions unchanged. So if say @oldbit is 5, then this routine |
1051 | * returns 13. | |
fb5eeeee PJ |
1052 | */ |
1053 | int bitmap_bitremap(int oldbit, const unsigned long *old, | |
1054 | const unsigned long *new, int bits) | |
1055 | { | |
96b7f341 PJ |
1056 | int w = bitmap_weight(new, bits); |
1057 | int n = bitmap_pos_to_ord(old, oldbit, bits); | |
1058 | if (n < 0 || w == 0) | |
1059 | return oldbit; | |
1060 | else | |
1061 | return bitmap_ord_to_pos(new, n % w, bits); | |
fb5eeeee | 1062 | } |
cde3d0f8 | 1063 | EXPORT_SYMBOL(bitmap_bitremap); |
fb5eeeee | 1064 | |
cde3d0f8 | 1065 | #ifdef CONFIG_NUMA |
7ea931c9 PJ |
1066 | /** |
1067 | * bitmap_onto - translate one bitmap relative to another | |
1068 | * @dst: resulting translated bitmap | |
1069 | * @orig: original untranslated bitmap | |
1070 | * @relmap: bitmap relative to which translated | |
1071 | * @bits: number of bits in each of these bitmaps | |
1072 | * | |
1073 | * Set the n-th bit of @dst iff there exists some m such that the | |
1074 | * n-th bit of @relmap is set, the m-th bit of @orig is set, and | |
1075 | * the n-th bit of @relmap is also the m-th _set_ bit of @relmap. | |
1076 | * (If you understood the previous sentence the first time your | |
1077 | * read it, you're overqualified for your current job.) | |
1078 | * | |
1079 | * In other words, @orig is mapped onto (surjectively) @dst, | |
da3dae54 | 1080 | * using the map { <n, m> | the n-th bit of @relmap is the |
7ea931c9 PJ |
1081 | * m-th set bit of @relmap }. |
1082 | * | |
1083 | * Any set bits in @orig above bit number W, where W is the | |
1084 | * weight of (number of set bits in) @relmap are mapped nowhere. | |
1085 | * In particular, if for all bits m set in @orig, m >= W, then | |
1086 | * @dst will end up empty. In situations where the possibility | |
1087 | * of such an empty result is not desired, one way to avoid it is | |
1088 | * to use the bitmap_fold() operator, below, to first fold the | |
1089 | * @orig bitmap over itself so that all its set bits x are in the | |
1090 | * range 0 <= x < W. The bitmap_fold() operator does this by | |
1091 | * setting the bit (m % W) in @dst, for each bit (m) set in @orig. | |
1092 | * | |
1093 | * Example [1] for bitmap_onto(): | |
1094 | * Let's say @relmap has bits 30-39 set, and @orig has bits | |
1095 | * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine, | |
1096 | * @dst will have bits 31, 33, 35, 37 and 39 set. | |
1097 | * | |
1098 | * When bit 0 is set in @orig, it means turn on the bit in | |
1099 | * @dst corresponding to whatever is the first bit (if any) | |
1100 | * that is turned on in @relmap. Since bit 0 was off in the | |
1101 | * above example, we leave off that bit (bit 30) in @dst. | |
1102 | * | |
1103 | * When bit 1 is set in @orig (as in the above example), it | |
1104 | * means turn on the bit in @dst corresponding to whatever | |
1105 | * is the second bit that is turned on in @relmap. The second | |
1106 | * bit in @relmap that was turned on in the above example was | |
1107 | * bit 31, so we turned on bit 31 in @dst. | |
1108 | * | |
1109 | * Similarly, we turned on bits 33, 35, 37 and 39 in @dst, | |
1110 | * because they were the 4th, 6th, 8th and 10th set bits | |
1111 | * set in @relmap, and the 4th, 6th, 8th and 10th bits of | |
1112 | * @orig (i.e. bits 3, 5, 7 and 9) were also set. | |
1113 | * | |
1114 | * When bit 11 is set in @orig, it means turn on the bit in | |
25985edc | 1115 | * @dst corresponding to whatever is the twelfth bit that is |
7ea931c9 PJ |
1116 | * turned on in @relmap. In the above example, there were |
1117 | * only ten bits turned on in @relmap (30..39), so that bit | |
1118 | * 11 was set in @orig had no affect on @dst. | |
1119 | * | |
1120 | * Example [2] for bitmap_fold() + bitmap_onto(): | |
40bf19a8 | 1121 | * Let's say @relmap has these ten bits set:: |
1122 | * | |
7ea931c9 | 1123 | * 40 41 42 43 45 48 53 61 74 95 |
40bf19a8 | 1124 | * |
7ea931c9 PJ |
1125 | * (for the curious, that's 40 plus the first ten terms of the |
1126 | * Fibonacci sequence.) | |
1127 | * | |
1128 | * Further lets say we use the following code, invoking | |
1129 | * bitmap_fold() then bitmap_onto, as suggested above to | |
40bf19a8 | 1130 | * avoid the possibility of an empty @dst result:: |
7ea931c9 PJ |
1131 | * |
1132 | * unsigned long *tmp; // a temporary bitmap's bits | |
1133 | * | |
1134 | * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits); | |
1135 | * bitmap_onto(dst, tmp, relmap, bits); | |
1136 | * | |
1137 | * Then this table shows what various values of @dst would be, for | |
1138 | * various @orig's. I list the zero-based positions of each set bit. | |
1139 | * The tmp column shows the intermediate result, as computed by | |
1140 | * using bitmap_fold() to fold the @orig bitmap modulo ten | |
40bf19a8 | 1141 | * (the weight of @relmap): |
7ea931c9 | 1142 | * |
40bf19a8 | 1143 | * =============== ============== ================= |
7ea931c9 PJ |
1144 | * @orig tmp @dst |
1145 | * 0 0 40 | |
1146 | * 1 1 41 | |
1147 | * 9 9 95 | |
40bf19a8 | 1148 | * 10 0 40 [#f1]_ |
7ea931c9 PJ |
1149 | * 1 3 5 7 1 3 5 7 41 43 48 61 |
1150 | * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45 | |
1151 | * 0 9 18 27 0 9 8 7 40 61 74 95 | |
1152 | * 0 10 20 30 0 40 | |
1153 | * 0 11 22 33 0 1 2 3 40 41 42 43 | |
1154 | * 0 12 24 36 0 2 4 6 40 42 45 53 | |
40bf19a8 | 1155 | * 78 102 211 1 2 8 41 42 74 [#f1]_ |
1156 | * =============== ============== ================= | |
1157 | * | |
1158 | * .. [#f1] | |
7ea931c9 | 1159 | * |
40bf19a8 | 1160 | * For these marked lines, if we hadn't first done bitmap_fold() |
7ea931c9 PJ |
1161 | * into tmp, then the @dst result would have been empty. |
1162 | * | |
1163 | * If either of @orig or @relmap is empty (no set bits), then @dst | |
1164 | * will be returned empty. | |
1165 | * | |
1166 | * If (as explained above) the only set bits in @orig are in positions | |
1167 | * m where m >= W, (where W is the weight of @relmap) then @dst will | |
1168 | * once again be returned empty. | |
1169 | * | |
1170 | * All bits in @dst not set by the above rule are cleared. | |
1171 | */ | |
1172 | void bitmap_onto(unsigned long *dst, const unsigned long *orig, | |
eb569883 | 1173 | const unsigned long *relmap, unsigned int bits) |
7ea931c9 | 1174 | { |
eb569883 | 1175 | unsigned int n, m; /* same meaning as in above comment */ |
7ea931c9 PJ |
1176 | |
1177 | if (dst == orig) /* following doesn't handle inplace mappings */ | |
1178 | return; | |
1179 | bitmap_zero(dst, bits); | |
1180 | ||
1181 | /* | |
1182 | * The following code is a more efficient, but less | |
1183 | * obvious, equivalent to the loop: | |
1184 | * for (m = 0; m < bitmap_weight(relmap, bits); m++) { | |
1185 | * n = bitmap_ord_to_pos(orig, m, bits); | |
1186 | * if (test_bit(m, orig)) | |
1187 | * set_bit(n, dst); | |
1188 | * } | |
1189 | */ | |
1190 | ||
1191 | m = 0; | |
08564fb7 | 1192 | for_each_set_bit(n, relmap, bits) { |
7ea931c9 PJ |
1193 | /* m == bitmap_pos_to_ord(relmap, n, bits) */ |
1194 | if (test_bit(m, orig)) | |
1195 | set_bit(n, dst); | |
1196 | m++; | |
1197 | } | |
1198 | } | |
7ea931c9 PJ |
1199 | |
1200 | /** | |
1201 | * bitmap_fold - fold larger bitmap into smaller, modulo specified size | |
1202 | * @dst: resulting smaller bitmap | |
1203 | * @orig: original larger bitmap | |
1204 | * @sz: specified size | |
b26ad583 | 1205 | * @nbits: number of bits in each of these bitmaps |
7ea931c9 PJ |
1206 | * |
1207 | * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst. | |
1208 | * Clear all other bits in @dst. See further the comment and | |
1209 | * Example [2] for bitmap_onto() for why and how to use this. | |
1210 | */ | |
1211 | void bitmap_fold(unsigned long *dst, const unsigned long *orig, | |
b26ad583 | 1212 | unsigned int sz, unsigned int nbits) |
7ea931c9 | 1213 | { |
b26ad583 | 1214 | unsigned int oldbit; |
7ea931c9 PJ |
1215 | |
1216 | if (dst == orig) /* following doesn't handle inplace mappings */ | |
1217 | return; | |
b26ad583 | 1218 | bitmap_zero(dst, nbits); |
7ea931c9 | 1219 | |
b26ad583 | 1220 | for_each_set_bit(oldbit, orig, nbits) |
7ea931c9 PJ |
1221 | set_bit(oldbit % sz, dst); |
1222 | } | |
cdc90a18 | 1223 | #endif /* CONFIG_NUMA */ |
7ea931c9 | 1224 | |
3cf64b93 PJ |
1225 | /* |
1226 | * Common code for bitmap_*_region() routines. | |
1227 | * bitmap: array of unsigned longs corresponding to the bitmap | |
1228 | * pos: the beginning of the region | |
1229 | * order: region size (log base 2 of number of bits) | |
1230 | * reg_op: operation(s) to perform on that region of bitmap | |
1da177e4 | 1231 | * |
3cf64b93 PJ |
1232 | * Can set, verify and/or release a region of bits in a bitmap, |
1233 | * depending on which combination of REG_OP_* flag bits is set. | |
1da177e4 | 1234 | * |
3cf64b93 PJ |
1235 | * A region of a bitmap is a sequence of bits in the bitmap, of |
1236 | * some size '1 << order' (a power of two), aligned to that same | |
1237 | * '1 << order' power of two. | |
1238 | * | |
1239 | * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits). | |
1240 | * Returns 0 in all other cases and reg_ops. | |
1da177e4 | 1241 | */ |
3cf64b93 PJ |
1242 | |
1243 | enum { | |
1244 | REG_OP_ISFREE, /* true if region is all zero bits */ | |
1245 | REG_OP_ALLOC, /* set all bits in region */ | |
1246 | REG_OP_RELEASE, /* clear all bits in region */ | |
1247 | }; | |
1248 | ||
9279d328 | 1249 | static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op) |
1da177e4 | 1250 | { |
3cf64b93 PJ |
1251 | int nbits_reg; /* number of bits in region */ |
1252 | int index; /* index first long of region in bitmap */ | |
1253 | int offset; /* bit offset region in bitmap[index] */ | |
1254 | int nlongs_reg; /* num longs spanned by region in bitmap */ | |
74373c6a | 1255 | int nbitsinlong; /* num bits of region in each spanned long */ |
3cf64b93 | 1256 | unsigned long mask; /* bitmask for one long of region */ |
74373c6a | 1257 | int i; /* scans bitmap by longs */ |
3cf64b93 | 1258 | int ret = 0; /* return value */ |
74373c6a | 1259 | |
3cf64b93 PJ |
1260 | /* |
1261 | * Either nlongs_reg == 1 (for small orders that fit in one long) | |
1262 | * or (offset == 0 && mask == ~0UL) (for larger multiword orders.) | |
1263 | */ | |
1264 | nbits_reg = 1 << order; | |
1265 | index = pos / BITS_PER_LONG; | |
1266 | offset = pos - (index * BITS_PER_LONG); | |
1267 | nlongs_reg = BITS_TO_LONGS(nbits_reg); | |
1268 | nbitsinlong = min(nbits_reg, BITS_PER_LONG); | |
1da177e4 | 1269 | |
3cf64b93 PJ |
1270 | /* |
1271 | * Can't do "mask = (1UL << nbitsinlong) - 1", as that | |
1272 | * overflows if nbitsinlong == BITS_PER_LONG. | |
1273 | */ | |
74373c6a | 1274 | mask = (1UL << (nbitsinlong - 1)); |
1da177e4 | 1275 | mask += mask - 1; |
3cf64b93 | 1276 | mask <<= offset; |
1da177e4 | 1277 | |
3cf64b93 PJ |
1278 | switch (reg_op) { |
1279 | case REG_OP_ISFREE: | |
1280 | for (i = 0; i < nlongs_reg; i++) { | |
1281 | if (bitmap[index + i] & mask) | |
1282 | goto done; | |
1283 | } | |
1284 | ret = 1; /* all bits in region free (zero) */ | |
1285 | break; | |
1286 | ||
1287 | case REG_OP_ALLOC: | |
1288 | for (i = 0; i < nlongs_reg; i++) | |
1289 | bitmap[index + i] |= mask; | |
1290 | break; | |
1291 | ||
1292 | case REG_OP_RELEASE: | |
1293 | for (i = 0; i < nlongs_reg; i++) | |
1294 | bitmap[index + i] &= ~mask; | |
1295 | break; | |
1da177e4 | 1296 | } |
3cf64b93 PJ |
1297 | done: |
1298 | return ret; | |
1299 | } | |
1300 | ||
1301 | /** | |
1302 | * bitmap_find_free_region - find a contiguous aligned mem region | |
1303 | * @bitmap: array of unsigned longs corresponding to the bitmap | |
1304 | * @bits: number of bits in the bitmap | |
1305 | * @order: region size (log base 2 of number of bits) to find | |
1306 | * | |
1307 | * Find a region of free (zero) bits in a @bitmap of @bits bits and | |
1308 | * allocate them (set them to one). Only consider regions of length | |
1309 | * a power (@order) of two, aligned to that power of two, which | |
1310 | * makes the search algorithm much faster. | |
1311 | * | |
1312 | * Return the bit offset in bitmap of the allocated region, | |
1313 | * or -errno on failure. | |
1314 | */ | |
9279d328 | 1315 | int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) |
3cf64b93 | 1316 | { |
9279d328 | 1317 | unsigned int pos, end; /* scans bitmap by regions of size order */ |
aa8e4fc6 | 1318 | |
9279d328 | 1319 | for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) { |
aa8e4fc6 LT |
1320 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
1321 | continue; | |
1322 | __reg_op(bitmap, pos, order, REG_OP_ALLOC); | |
1323 | return pos; | |
1324 | } | |
1325 | return -ENOMEM; | |
1da177e4 LT |
1326 | } |
1327 | EXPORT_SYMBOL(bitmap_find_free_region); | |
1328 | ||
1329 | /** | |
87e24802 | 1330 | * bitmap_release_region - release allocated bitmap region |
3cf64b93 PJ |
1331 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1332 | * @pos: beginning of bit region to release | |
1333 | * @order: region size (log base 2 of number of bits) to release | |
1da177e4 | 1334 | * |
72fd4a35 | 1335 | * This is the complement to __bitmap_find_free_region() and releases |
1da177e4 | 1336 | * the found region (by clearing it in the bitmap). |
3cf64b93 PJ |
1337 | * |
1338 | * No return value. | |
1da177e4 | 1339 | */ |
9279d328 | 1340 | void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4 | 1341 | { |
3cf64b93 | 1342 | __reg_op(bitmap, pos, order, REG_OP_RELEASE); |
1da177e4 LT |
1343 | } |
1344 | EXPORT_SYMBOL(bitmap_release_region); | |
1345 | ||
87e24802 PJ |
1346 | /** |
1347 | * bitmap_allocate_region - allocate bitmap region | |
3cf64b93 PJ |
1348 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1349 | * @pos: beginning of bit region to allocate | |
1350 | * @order: region size (log base 2 of number of bits) to allocate | |
87e24802 PJ |
1351 | * |
1352 | * Allocate (set bits in) a specified region of a bitmap. | |
3cf64b93 | 1353 | * |
6e1907ff | 1354 | * Return 0 on success, or %-EBUSY if specified region wasn't |
87e24802 PJ |
1355 | * free (not all bits were zero). |
1356 | */ | |
9279d328 | 1357 | int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4 | 1358 | { |
3cf64b93 PJ |
1359 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
1360 | return -EBUSY; | |
2ac521d3 | 1361 | return __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
1da177e4 LT |
1362 | } |
1363 | EXPORT_SYMBOL(bitmap_allocate_region); | |
ccbe329b DV |
1364 | |
1365 | /** | |
1366 | * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. | |
1367 | * @dst: destination buffer | |
1368 | * @src: bitmap to copy | |
1369 | * @nbits: number of bits in the bitmap | |
1370 | * | |
1371 | * Require nbits % BITS_PER_LONG == 0. | |
1372 | */ | |
e8f24278 | 1373 | #ifdef __BIG_ENDIAN |
9b6c2d2e | 1374 | void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) |
ccbe329b | 1375 | { |
9b6c2d2e | 1376 | unsigned int i; |
ccbe329b DV |
1377 | |
1378 | for (i = 0; i < nbits/BITS_PER_LONG; i++) { | |
1379 | if (BITS_PER_LONG == 64) | |
9b6c2d2e | 1380 | dst[i] = cpu_to_le64(src[i]); |
ccbe329b | 1381 | else |
9b6c2d2e | 1382 | dst[i] = cpu_to_le32(src[i]); |
ccbe329b DV |
1383 | } |
1384 | } | |
1385 | EXPORT_SYMBOL(bitmap_copy_le); | |
e8f24278 | 1386 | #endif |
c724f193 | 1387 | |
c42b65e3 AS |
1388 | unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) |
1389 | { | |
1390 | return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long), | |
1391 | flags); | |
1392 | } | |
1393 | EXPORT_SYMBOL(bitmap_alloc); | |
1394 | ||
1395 | unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags) | |
1396 | { | |
1397 | return bitmap_alloc(nbits, flags | __GFP_ZERO); | |
1398 | } | |
1399 | EXPORT_SYMBOL(bitmap_zalloc); | |
1400 | ||
7529cc7f TT |
1401 | unsigned long *bitmap_alloc_node(unsigned int nbits, gfp_t flags, int node) |
1402 | { | |
1403 | return kmalloc_array_node(BITS_TO_LONGS(nbits), sizeof(unsigned long), | |
1404 | flags, node); | |
1405 | } | |
1406 | EXPORT_SYMBOL(bitmap_alloc_node); | |
1407 | ||
1408 | unsigned long *bitmap_zalloc_node(unsigned int nbits, gfp_t flags, int node) | |
1409 | { | |
1410 | return bitmap_alloc_node(nbits, flags | __GFP_ZERO, node); | |
1411 | } | |
1412 | EXPORT_SYMBOL(bitmap_zalloc_node); | |
1413 | ||
c42b65e3 AS |
1414 | void bitmap_free(const unsigned long *bitmap) |
1415 | { | |
1416 | kfree(bitmap); | |
1417 | } | |
1418 | EXPORT_SYMBOL(bitmap_free); | |
1419 | ||
e829c2e4 BG |
1420 | static void devm_bitmap_free(void *data) |
1421 | { | |
1422 | unsigned long *bitmap = data; | |
1423 | ||
1424 | bitmap_free(bitmap); | |
1425 | } | |
1426 | ||
1427 | unsigned long *devm_bitmap_alloc(struct device *dev, | |
1428 | unsigned int nbits, gfp_t flags) | |
1429 | { | |
1430 | unsigned long *bitmap; | |
1431 | int ret; | |
1432 | ||
1433 | bitmap = bitmap_alloc(nbits, flags); | |
1434 | if (!bitmap) | |
1435 | return NULL; | |
1436 | ||
1437 | ret = devm_add_action_or_reset(dev, devm_bitmap_free, bitmap); | |
1438 | if (ret) | |
1439 | return NULL; | |
1440 | ||
1441 | return bitmap; | |
1442 | } | |
1443 | EXPORT_SYMBOL_GPL(devm_bitmap_alloc); | |
1444 | ||
1445 | unsigned long *devm_bitmap_zalloc(struct device *dev, | |
1446 | unsigned int nbits, gfp_t flags) | |
1447 | { | |
1448 | return devm_bitmap_alloc(dev, nbits, flags | __GFP_ZERO); | |
1449 | } | |
1450 | EXPORT_SYMBOL_GPL(devm_bitmap_zalloc); | |
1451 | ||
c724f193 YN |
1452 | #if BITS_PER_LONG == 64 |
1453 | /** | |
1454 | * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap | |
1455 | * @bitmap: array of unsigned longs, the destination bitmap | |
1456 | * @buf: array of u32 (in host byte order), the source bitmap | |
1457 | * @nbits: number of bits in @bitmap | |
1458 | */ | |
ccf7a6d4 | 1459 | void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits) |
c724f193 YN |
1460 | { |
1461 | unsigned int i, halfwords; | |
1462 | ||
c724f193 YN |
1463 | halfwords = DIV_ROUND_UP(nbits, 32); |
1464 | for (i = 0; i < halfwords; i++) { | |
1465 | bitmap[i/2] = (unsigned long) buf[i]; | |
1466 | if (++i < halfwords) | |
1467 | bitmap[i/2] |= ((unsigned long) buf[i]) << 32; | |
1468 | } | |
1469 | ||
1470 | /* Clear tail bits in last word beyond nbits. */ | |
1471 | if (nbits % BITS_PER_LONG) | |
1472 | bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits); | |
1473 | } | |
1474 | EXPORT_SYMBOL(bitmap_from_arr32); | |
1475 | ||
1476 | /** | |
1477 | * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits | |
1478 | * @buf: array of u32 (in host byte order), the dest bitmap | |
1479 | * @bitmap: array of unsigned longs, the source bitmap | |
1480 | * @nbits: number of bits in @bitmap | |
1481 | */ | |
1482 | void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits) | |
1483 | { | |
1484 | unsigned int i, halfwords; | |
1485 | ||
c724f193 YN |
1486 | halfwords = DIV_ROUND_UP(nbits, 32); |
1487 | for (i = 0; i < halfwords; i++) { | |
1488 | buf[i] = (u32) (bitmap[i/2] & UINT_MAX); | |
1489 | if (++i < halfwords) | |
1490 | buf[i] = (u32) (bitmap[i/2] >> 32); | |
1491 | } | |
1492 | ||
1493 | /* Clear tail bits in last element of array beyond nbits. */ | |
1494 | if (nbits % BITS_PER_LONG) | |
1495 | buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31)); | |
1496 | } | |
1497 | EXPORT_SYMBOL(bitmap_to_arr32); | |
1498 | ||
1499 | #endif |