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1 | /* |
2 | * lib/bitmap.c |
3 | * Helper functions for bitmap.h. |
4 | * |
5 | * This source code is licensed under the GNU General Public License, |
6 | * Version 2. See the file COPYING for more details. |
7 | */ |
8 | #include <linux/module.h> |
9 | #include <linux/ctype.h> |
10 | #include <linux/errno.h> |
11 | #include <linux/bitmap.h> |
12 | #include <linux/bitops.h> |
13 | #include <asm/uaccess.h> |
14 | |
15 | /* |
16 | * bitmaps provide an array of bits, implemented using an an |
17 | * array of unsigned longs. The number of valid bits in a |
18 | * given bitmap does _not_ need to be an exact multiple of |
19 | * BITS_PER_LONG. |
20 | * |
21 | * The possible unused bits in the last, partially used word |
22 | * of a bitmap are 'don't care'. The implementation makes |
23 | * no particular effort to keep them zero. It ensures that |
24 | * their value will not affect the results of any operation. |
25 | * The bitmap operations that return Boolean (bitmap_empty, |
26 | * for example) or scalar (bitmap_weight, for example) results |
27 | * carefully filter out these unused bits from impacting their |
28 | * results. |
29 | * |
30 | * These operations actually hold to a slightly stronger rule: |
31 | * if you don't input any bitmaps to these ops that have some |
32 | * unused bits set, then they won't output any set unused bits |
33 | * in output bitmaps. |
34 | * |
35 | * The byte ordering of bitmaps is more natural on little |
36 | * endian architectures. See the big-endian headers |
37 | * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h |
38 | * for the best explanations of this ordering. |
39 | */ |
40 | |
41 | int __bitmap_empty(const unsigned long *bitmap, int bits) |
42 | { |
43 | int k, lim = bits/BITS_PER_LONG; |
44 | for (k = 0; k < lim; ++k) |
45 | if (bitmap[k]) |
46 | return 0; |
47 | |
48 | if (bits % BITS_PER_LONG) |
49 | if (bitmap[k] & BITMAP_LAST_WORD_MASK(bits)) |
50 | return 0; |
51 | |
52 | return 1; |
53 | } |
54 | EXPORT_SYMBOL(__bitmap_empty); |
55 | |
56 | int __bitmap_full(const unsigned long *bitmap, int bits) |
57 | { |
58 | int k, lim = bits/BITS_PER_LONG; |
59 | for (k = 0; k < lim; ++k) |
60 | if (~bitmap[k]) |
61 | return 0; |
62 | |
63 | if (bits % BITS_PER_LONG) |
64 | if (~bitmap[k] & BITMAP_LAST_WORD_MASK(bits)) |
65 | return 0; |
66 | |
67 | return 1; |
68 | } |
69 | EXPORT_SYMBOL(__bitmap_full); |
70 | |
71 | int __bitmap_equal(const unsigned long *bitmap1, |
72 | const unsigned long *bitmap2, int bits) |
73 | { |
74 | int k, lim = bits/BITS_PER_LONG; |
75 | for (k = 0; k < lim; ++k) |
76 | if (bitmap1[k] != bitmap2[k]) |
77 | return 0; |
78 | |
79 | if (bits % BITS_PER_LONG) |
80 | if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) |
81 | return 0; |
82 | |
83 | return 1; |
84 | } |
85 | EXPORT_SYMBOL(__bitmap_equal); |
86 | |
87 | void __bitmap_complement(unsigned long *dst, const unsigned long *src, int bits) |
88 | { |
89 | int k, lim = bits/BITS_PER_LONG; |
90 | for (k = 0; k < lim; ++k) |
91 | dst[k] = ~src[k]; |
92 | |
93 | if (bits % BITS_PER_LONG) |
94 | dst[k] = ~src[k] & BITMAP_LAST_WORD_MASK(bits); |
95 | } |
96 | EXPORT_SYMBOL(__bitmap_complement); |
97 | |
98 | /** |
99 | * __bitmap_shift_right - logical right shift of the bits in a bitmap |
100 | * @dst : destination bitmap |
101 | * @src : source bitmap |
102 | * @shift : shift by this many bits |
103 | * @bits : bitmap size, in bits |
104 | * |
105 | * Shifting right (dividing) means moving bits in the MS -> LS bit |
106 | * direction. Zeros are fed into the vacated MS positions and the |
107 | * LS bits shifted off the bottom are lost. |
108 | */ |
109 | void __bitmap_shift_right(unsigned long *dst, |
110 | const unsigned long *src, int shift, int bits) |
111 | { |
112 | int k, lim = BITS_TO_LONGS(bits), left = bits % BITS_PER_LONG; |
113 | int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
114 | unsigned long mask = (1UL << left) - 1; |
115 | for (k = 0; off + k < lim; ++k) { |
116 | unsigned long upper, lower; |
117 | |
118 | /* |
119 | * If shift is not word aligned, take lower rem bits of |
120 | * word above and make them the top rem bits of result. |
121 | */ |
122 | if (!rem || off + k + 1 >= lim) |
123 | upper = 0; |
124 | else { |
125 | upper = src[off + k + 1]; |
126 | if (off + k + 1 == lim - 1 && left) |
127 | upper &= mask; |
128 | } |
129 | lower = src[off + k]; |
130 | if (left && off + k == lim - 1) |
131 | lower &= mask; |
132 | dst[k] = upper << (BITS_PER_LONG - rem) | lower >> rem; |
133 | if (left && k == lim - 1) |
134 | dst[k] &= mask; |
135 | } |
136 | if (off) |
137 | memset(&dst[lim - off], 0, off*sizeof(unsigned long)); |
138 | } |
139 | EXPORT_SYMBOL(__bitmap_shift_right); |
140 | |
141 | |
142 | /** |
143 | * __bitmap_shift_left - logical left shift of the bits in a bitmap |
144 | * @dst : destination bitmap |
145 | * @src : source bitmap |
146 | * @shift : shift by this many bits |
147 | * @bits : bitmap size, in bits |
148 | * |
149 | * Shifting left (multiplying) means moving bits in the LS -> MS |
150 | * direction. Zeros are fed into the vacated LS bit positions |
151 | * and those MS bits shifted off the top are lost. |
152 | */ |
153 | |
154 | void __bitmap_shift_left(unsigned long *dst, |
155 | const unsigned long *src, int shift, int bits) |
156 | { |
157 | int k, lim = BITS_TO_LONGS(bits), left = bits % BITS_PER_LONG; |
158 | int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
159 | for (k = lim - off - 1; k >= 0; --k) { |
160 | unsigned long upper, lower; |
161 | |
162 | /* |
163 | * If shift is not word aligned, take upper rem bits of |
164 | * word below and make them the bottom rem bits of result. |
165 | */ |
166 | if (rem && k > 0) |
167 | lower = src[k - 1]; |
168 | else |
169 | lower = 0; |
170 | upper = src[k]; |
171 | if (left && k == lim - 1) |
172 | upper &= (1UL << left) - 1; |
173 | dst[k + off] = lower >> (BITS_PER_LONG - rem) | upper << rem; |
174 | if (left && k + off == lim - 1) |
175 | dst[k + off] &= (1UL << left) - 1; |
176 | } |
177 | if (off) |
178 | memset(dst, 0, off*sizeof(unsigned long)); |
179 | } |
180 | EXPORT_SYMBOL(__bitmap_shift_left); |
181 | |
182 | int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
183 | const unsigned long *bitmap2, int bits) |
184 | { |
185 | int k; |
186 | int nr = BITS_TO_LONGS(bits); |
187 | unsigned long result = 0; |
188 | |
189 | for (k = 0; k < nr; k++) |
190 | result |= (dst[k] = bitmap1[k] & bitmap2[k]); |
191 | return result != 0; |
192 | } |
193 | EXPORT_SYMBOL(__bitmap_and); |
194 | |
195 | void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, |
196 | const unsigned long *bitmap2, int bits) |
197 | { |
198 | int k; |
199 | int nr = BITS_TO_LONGS(bits); |
200 | |
201 | for (k = 0; k < nr; k++) |
202 | dst[k] = bitmap1[k] | bitmap2[k]; |
203 | } |
204 | EXPORT_SYMBOL(__bitmap_or); |
205 | |
206 | void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, |
207 | const unsigned long *bitmap2, int bits) |
208 | { |
209 | int k; |
210 | int nr = BITS_TO_LONGS(bits); |
211 | |
212 | for (k = 0; k < nr; k++) |
213 | dst[k] = bitmap1[k] ^ bitmap2[k]; |
214 | } |
215 | EXPORT_SYMBOL(__bitmap_xor); |
216 | |
217 | int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
218 | const unsigned long *bitmap2, int bits) |
219 | { |
220 | int k; |
221 | int nr = BITS_TO_LONGS(bits); |
222 | unsigned long result = 0; |
223 | |
224 | for (k = 0; k < nr; k++) |
225 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k]); |
226 | return result != 0; |
227 | } |
228 | EXPORT_SYMBOL(__bitmap_andnot); |
229 | |
230 | int __bitmap_intersects(const unsigned long *bitmap1, |
231 | const unsigned long *bitmap2, int bits) |
232 | { |
233 | int k, lim = bits/BITS_PER_LONG; |
234 | for (k = 0; k < lim; ++k) |
235 | if (bitmap1[k] & bitmap2[k]) |
236 | return 1; |
237 | |
238 | if (bits % BITS_PER_LONG) |
239 | if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) |
240 | return 1; |
241 | return 0; |
242 | } |
243 | EXPORT_SYMBOL(__bitmap_intersects); |
244 | |
245 | int __bitmap_subset(const unsigned long *bitmap1, |
246 | const unsigned long *bitmap2, int bits) |
247 | { |
248 | int k, lim = bits/BITS_PER_LONG; |
249 | for (k = 0; k < lim; ++k) |
250 | if (bitmap1[k] & ~bitmap2[k]) |
251 | return 0; |
252 | |
253 | if (bits % BITS_PER_LONG) |
254 | if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) |
255 | return 0; |
256 | return 1; |
257 | } |
258 | EXPORT_SYMBOL(__bitmap_subset); |
259 | |
260 | int __bitmap_weight(const unsigned long *bitmap, int bits) |
261 | { |
262 | int k, w = 0, lim = bits/BITS_PER_LONG; |
263 | |
264 | for (k = 0; k < lim; k++) |
265 | w += hweight_long(bitmap[k]); |
266 | |
267 | if (bits % BITS_PER_LONG) |
268 | w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits)); |
269 | |
270 | return w; |
271 | } |
272 | EXPORT_SYMBOL(__bitmap_weight); |
273 | |
274 | #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG)) |
275 | |
276 | void bitmap_set(unsigned long *map, int start, int nr) |
277 | { |
278 | unsigned long *p = map + BIT_WORD(start); |
279 | const int size = start + nr; |
280 | int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); |
281 | unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); |
282 | |
283 | while (nr - bits_to_set >= 0) { |
284 | *p |= mask_to_set; |
285 | nr -= bits_to_set; |
286 | bits_to_set = BITS_PER_LONG; |
287 | mask_to_set = ~0UL; |
288 | p++; |
289 | } |
290 | if (nr) { |
291 | mask_to_set &= BITMAP_LAST_WORD_MASK(size); |
292 | *p |= mask_to_set; |
293 | } |
294 | } |
295 | EXPORT_SYMBOL(bitmap_set); |
296 | |
297 | void bitmap_clear(unsigned long *map, int start, int nr) |
298 | { |
299 | unsigned long *p = map + BIT_WORD(start); |
300 | const int size = start + nr; |
301 | int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); |
302 | unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); |
303 | |
304 | while (nr - bits_to_clear >= 0) { |
305 | *p &= ~mask_to_clear; |
306 | nr -= bits_to_clear; |
307 | bits_to_clear = BITS_PER_LONG; |
308 | mask_to_clear = ~0UL; |
309 | p++; |
310 | } |
311 | if (nr) { |
312 | mask_to_clear &= BITMAP_LAST_WORD_MASK(size); |
313 | *p &= ~mask_to_clear; |
314 | } |
315 | } |
316 | EXPORT_SYMBOL(bitmap_clear); |
317 | |
318 | /* |
319 | * bitmap_find_next_zero_area - find a contiguous aligned zero area |
320 | * @map: The address to base the search on |
321 | * @size: The bitmap size in bits |
322 | * @start: The bitnumber to start searching at |
323 | * @nr: The number of zeroed bits we're looking for |
324 | * @align_mask: Alignment mask for zero area |
325 | * |
326 | * The @align_mask should be one less than a power of 2; the effect is that |
327 | * the bit offset of all zero areas this function finds is multiples of that |
328 | * power of 2. A @align_mask of 0 means no alignment is required. |
329 | */ |
330 | unsigned long bitmap_find_next_zero_area(unsigned long *map, |
331 | unsigned long size, |
332 | unsigned long start, |
333 | unsigned int nr, |
334 | unsigned long align_mask) |
335 | { |
336 | unsigned long index, end, i; |
337 | again: |
338 | index = find_next_zero_bit(map, size, start); |
339 | |
340 | /* Align allocation */ |
341 | index = __ALIGN_MASK(index, align_mask); |
342 | |
343 | end = index + nr; |
344 | if (end > size) |
345 | return end; |
346 | i = find_next_bit(map, end, index); |
347 | if (i < end) { |
348 | start = i + 1; |
349 | goto again; |
350 | } |
351 | return index; |
352 | } |
353 | EXPORT_SYMBOL(bitmap_find_next_zero_area); |
354 | |
355 | /* |
356 | * Bitmap printing & parsing functions: first version by Bill Irwin, |
357 | * second version by Paul Jackson, third by Joe Korty. |
358 | */ |
359 | |
360 | #define CHUNKSZ 32 |
361 | #define nbits_to_hold_value(val) fls(val) |
362 | #define BASEDEC 10 /* fancier cpuset lists input in decimal */ |
363 | |
364 | /** |
365 | * bitmap_scnprintf - convert bitmap to an ASCII hex string. |
366 | * @buf: byte buffer into which string is placed |
367 | * @buflen: reserved size of @buf, in bytes |
368 | * @maskp: pointer to bitmap to convert |
369 | * @nmaskbits: size of bitmap, in bits |
370 | * |
371 | * Exactly @nmaskbits bits are displayed. Hex digits are grouped into |
372 | * comma-separated sets of eight digits per set. |
373 | */ |
374 | int bitmap_scnprintf(char *buf, unsigned int buflen, |
375 | const unsigned long *maskp, int nmaskbits) |
376 | { |
377 | int i, word, bit, len = 0; |
378 | unsigned long val; |
379 | const char *sep = ""; |
380 | int chunksz; |
381 | u32 chunkmask; |
382 | |
383 | chunksz = nmaskbits & (CHUNKSZ - 1); |
384 | if (chunksz == 0) |
385 | chunksz = CHUNKSZ; |
386 | |
387 | i = ALIGN(nmaskbits, CHUNKSZ) - CHUNKSZ; |
388 | for (; i >= 0; i -= CHUNKSZ) { |
389 | chunkmask = ((1ULL << chunksz) - 1); |
390 | word = i / BITS_PER_LONG; |
391 | bit = i % BITS_PER_LONG; |
392 | val = (maskp[word] >> bit) & chunkmask; |
393 | len += scnprintf(buf+len, buflen-len, "%s%0*lx", sep, |
394 | (chunksz+3)/4, val); |
395 | chunksz = CHUNKSZ; |
396 | sep = ","; |
397 | } |
398 | return len; |
399 | } |
400 | EXPORT_SYMBOL(bitmap_scnprintf); |
401 | |
402 | /** |
403 | * __bitmap_parse - convert an ASCII hex string into a bitmap. |
404 | * @buf: pointer to buffer containing string. |
405 | * @buflen: buffer size in bytes. If string is smaller than this |
406 | * then it must be terminated with a \0. |
407 | * @is_user: location of buffer, 0 indicates kernel space |
408 | * @maskp: pointer to bitmap array that will contain result. |
409 | * @nmaskbits: size of bitmap, in bits. |
410 | * |
411 | * Commas group hex digits into chunks. Each chunk defines exactly 32 |
412 | * bits of the resultant bitmask. No chunk may specify a value larger |
413 | * than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value |
414 | * then leading 0-bits are prepended. %-EINVAL is returned for illegal |
415 | * characters and for grouping errors such as "1,,5", ",44", "," and "". |
416 | * Leading and trailing whitespace accepted, but not embedded whitespace. |
417 | */ |
418 | int __bitmap_parse(const char *buf, unsigned int buflen, |
419 | int is_user, unsigned long *maskp, |
420 | int nmaskbits) |
421 | { |
422 | int c, old_c, totaldigits, ndigits, nchunks, nbits; |
423 | u32 chunk; |
424 | const char __user *ubuf = buf; |
425 | |
426 | bitmap_zero(maskp, nmaskbits); |
427 | |
428 | nchunks = nbits = totaldigits = c = 0; |
429 | do { |
430 | chunk = ndigits = 0; |
431 | |
432 | /* Get the next chunk of the bitmap */ |
433 | while (buflen) { |
434 | old_c = c; |
435 | if (is_user) { |
436 | if (__get_user(c, ubuf++)) |
437 | return -EFAULT; |
438 | } |
439 | else |
440 | c = *buf++; |
441 | buflen--; |
442 | if (isspace(c)) |
443 | continue; |
444 | |
445 | /* |
446 | * If the last character was a space and the current |
447 | * character isn't '\0', we've got embedded whitespace. |
448 | * This is a no-no, so throw an error. |
449 | */ |
450 | if (totaldigits && c && isspace(old_c)) |
451 | return -EINVAL; |
452 | |
453 | /* A '\0' or a ',' signal the end of the chunk */ |
454 | if (c == '\0' || c == ',') |
455 | break; |
456 | |
457 | if (!isxdigit(c)) |
458 | return -EINVAL; |
459 | |
460 | /* |
461 | * Make sure there are at least 4 free bits in 'chunk'. |
462 | * If not, this hexdigit will overflow 'chunk', so |
463 | * throw an error. |
464 | */ |
465 | if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1)) |
466 | return -EOVERFLOW; |
467 | |
468 | chunk = (chunk << 4) | hex_to_bin(c); |
469 | ndigits++; totaldigits++; |
470 | } |
471 | if (ndigits == 0) |
472 | return -EINVAL; |
473 | if (nchunks == 0 && chunk == 0) |
474 | continue; |
475 | |
476 | __bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits); |
477 | *maskp |= chunk; |
478 | nchunks++; |
479 | nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ; |
480 | if (nbits > nmaskbits) |
481 | return -EOVERFLOW; |
482 | } while (buflen && c == ','); |
483 | |
484 | return 0; |
485 | } |
486 | EXPORT_SYMBOL(__bitmap_parse); |
487 | |
488 | /** |
489 | * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap |
490 | * |
491 | * @ubuf: pointer to user buffer containing string. |
492 | * @ulen: buffer size in bytes. If string is smaller than this |
493 | * then it must be terminated with a \0. |
494 | * @maskp: pointer to bitmap array that will contain result. |
495 | * @nmaskbits: size of bitmap, in bits. |
496 | * |
497 | * Wrapper for __bitmap_parse(), providing it with user buffer. |
498 | * |
499 | * We cannot have this as an inline function in bitmap.h because it needs |
500 | * linux/uaccess.h to get the access_ok() declaration and this causes |
501 | * cyclic dependencies. |
502 | */ |
503 | int bitmap_parse_user(const char __user *ubuf, |
504 | unsigned int ulen, unsigned long *maskp, |
505 | int nmaskbits) |
506 | { |
507 | if (!access_ok(VERIFY_READ, ubuf, ulen)) |
508 | return -EFAULT; |
509 | return __bitmap_parse((const char *)ubuf, ulen, 1, maskp, nmaskbits); |
510 | } |
511 | EXPORT_SYMBOL(bitmap_parse_user); |
512 | |
513 | /* |
514 | * bscnl_emit(buf, buflen, rbot, rtop, bp) |
515 | * |
516 | * Helper routine for bitmap_scnlistprintf(). Write decimal number |
517 | * or range to buf, suppressing output past buf+buflen, with optional |
518 | * comma-prefix. Return len of what would be written to buf, if it |
519 | * all fit. |
520 | */ |
521 | static inline int bscnl_emit(char *buf, int buflen, int rbot, int rtop, int len) |
522 | { |
523 | if (len > 0) |
524 | len += scnprintf(buf + len, buflen - len, ","); |
525 | if (rbot == rtop) |
526 | len += scnprintf(buf + len, buflen - len, "%d", rbot); |
527 | else |
528 | len += scnprintf(buf + len, buflen - len, "%d-%d", rbot, rtop); |
529 | return len; |
530 | } |
531 | |
532 | /** |
533 | * bitmap_scnlistprintf - convert bitmap to list format ASCII string |
534 | * @buf: byte buffer into which string is placed |
535 | * @buflen: reserved size of @buf, in bytes |
536 | * @maskp: pointer to bitmap to convert |
537 | * @nmaskbits: size of bitmap, in bits |
538 | * |
539 | * Output format is a comma-separated list of decimal numbers and |
540 | * ranges. Consecutively set bits are shown as two hyphen-separated |
541 | * decimal numbers, the smallest and largest bit numbers set in |
542 | * the range. Output format is compatible with the format |
543 | * accepted as input by bitmap_parselist(). |
544 | * |
545 | * The return value is the number of characters which would be |
546 | * generated for the given input, excluding the trailing '\0', as |
547 | * per ISO C99. |
548 | */ |
549 | int bitmap_scnlistprintf(char *buf, unsigned int buflen, |
550 | const unsigned long *maskp, int nmaskbits) |
551 | { |
552 | int len = 0; |
553 | /* current bit is 'cur', most recently seen range is [rbot, rtop] */ |
554 | int cur, rbot, rtop; |
555 | |
556 | if (buflen == 0) |
557 | return 0; |
558 | buf[0] = 0; |
559 | |
560 | rbot = cur = find_first_bit(maskp, nmaskbits); |
561 | while (cur < nmaskbits) { |
562 | rtop = cur; |
563 | cur = find_next_bit(maskp, nmaskbits, cur+1); |
564 | if (cur >= nmaskbits || cur > rtop + 1) { |
565 | len = bscnl_emit(buf, buflen, rbot, rtop, len); |
566 | rbot = cur; |
567 | } |
568 | } |
569 | return len; |
570 | } |
571 | EXPORT_SYMBOL(bitmap_scnlistprintf); |
572 | |
573 | /** |
574 | * __bitmap_parselist - convert list format ASCII string to bitmap |
575 | * @buf: read nul-terminated user string from this buffer |
576 | * @buflen: buffer size in bytes. If string is smaller than this |
577 | * then it must be terminated with a \0. |
578 | * @is_user: location of buffer, 0 indicates kernel space |
579 | * @maskp: write resulting mask here |
580 | * @nmaskbits: number of bits in mask to be written |
581 | * |
582 | * Input format is a comma-separated list of decimal numbers and |
583 | * ranges. Consecutively set bits are shown as two hyphen-separated |
584 | * decimal numbers, the smallest and largest bit numbers set in |
585 | * the range. |
586 | * |
587 | * Returns 0 on success, -errno on invalid input strings. |
588 | * Error values: |
589 | * %-EINVAL: second number in range smaller than first |
590 | * %-EINVAL: invalid character in string |
591 | * %-ERANGE: bit number specified too large for mask |
592 | */ |
593 | static int __bitmap_parselist(const char *buf, unsigned int buflen, |
594 | int is_user, unsigned long *maskp, |
595 | int nmaskbits) |
596 | { |
597 | unsigned a, b; |
598 | int c, old_c, totaldigits; |
599 | const char __user *ubuf = buf; |
600 | int exp_digit, in_range; |
601 | |
602 | totaldigits = c = 0; |
603 | bitmap_zero(maskp, nmaskbits); |
604 | do { |
605 | exp_digit = 1; |
606 | in_range = 0; |
607 | a = b = 0; |
608 | |
609 | /* Get the next cpu# or a range of cpu#'s */ |
610 | while (buflen) { |
611 | old_c = c; |
612 | if (is_user) { |
613 | if (__get_user(c, ubuf++)) |
614 | return -EFAULT; |
615 | } else |
616 | c = *buf++; |
617 | buflen--; |
618 | if (isspace(c)) |
619 | continue; |
620 | |
621 | /* |
622 | * If the last character was a space and the current |
623 | * character isn't '\0', we've got embedded whitespace. |
624 | * This is a no-no, so throw an error. |
625 | */ |
626 | if (totaldigits && c && isspace(old_c)) |
627 | return -EINVAL; |
628 | |
629 | /* A '\0' or a ',' signal the end of a cpu# or range */ |
630 | if (c == '\0' || c == ',') |
631 | break; |
632 | |
633 | if (c == '-') { |
634 | if (exp_digit || in_range) |
635 | return -EINVAL; |
636 | b = 0; |
637 | in_range = 1; |
638 | exp_digit = 1; |
639 | continue; |
640 | } |
641 | |
642 | if (!isdigit(c)) |
643 | return -EINVAL; |
644 | |
645 | b = b * 10 + (c - '0'); |
646 | if (!in_range) |
647 | a = b; |
648 | exp_digit = 0; |
649 | totaldigits++; |
650 | } |
651 | if (!(a <= b)) |
652 | return -EINVAL; |
653 | if (b >= nmaskbits) |
654 | return -ERANGE; |
655 | while (a <= b) { |
656 | set_bit(a, maskp); |
657 | a++; |
658 | } |
659 | } while (buflen && c == ','); |
660 | return 0; |
661 | } |
662 | |
663 | int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits) |
664 | { |
665 | char *nl = strchr(bp, '\n'); |
666 | int len; |
667 | |
668 | if (nl) |
669 | len = nl - bp; |
670 | else |
671 | len = strlen(bp); |
672 | |
673 | return __bitmap_parselist(bp, len, 0, maskp, nmaskbits); |
674 | } |
675 | EXPORT_SYMBOL(bitmap_parselist); |
676 | |
677 | |
678 | /** |
679 | * bitmap_parselist_user() |
680 | * |
681 | * @ubuf: pointer to user buffer containing string. |
682 | * @ulen: buffer size in bytes. If string is smaller than this |
683 | * then it must be terminated with a \0. |
684 | * @maskp: pointer to bitmap array that will contain result. |
685 | * @nmaskbits: size of bitmap, in bits. |
686 | * |
687 | * Wrapper for bitmap_parselist(), providing it with user buffer. |
688 | * |
689 | * We cannot have this as an inline function in bitmap.h because it needs |
690 | * linux/uaccess.h to get the access_ok() declaration and this causes |
691 | * cyclic dependencies. |
692 | */ |
693 | int bitmap_parselist_user(const char __user *ubuf, |
694 | unsigned int ulen, unsigned long *maskp, |
695 | int nmaskbits) |
696 | { |
697 | if (!access_ok(VERIFY_READ, ubuf, ulen)) |
698 | return -EFAULT; |
699 | return __bitmap_parselist((const char *)ubuf, |
700 | ulen, 1, maskp, nmaskbits); |
701 | } |
702 | EXPORT_SYMBOL(bitmap_parselist_user); |
703 | |
704 | |
705 | /** |
706 | * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap |
707 | * @buf: pointer to a bitmap |
708 | * @pos: a bit position in @buf (0 <= @pos < @bits) |
709 | * @bits: number of valid bit positions in @buf |
710 | * |
711 | * Map the bit at position @pos in @buf (of length @bits) to the |
712 | * ordinal of which set bit it is. If it is not set or if @pos |
713 | * is not a valid bit position, map to -1. |
714 | * |
715 | * If for example, just bits 4 through 7 are set in @buf, then @pos |
716 | * values 4 through 7 will get mapped to 0 through 3, respectively, |
717 | * and other @pos values will get mapped to 0. When @pos value 7 |
718 | * gets mapped to (returns) @ord value 3 in this example, that means |
719 | * that bit 7 is the 3rd (starting with 0th) set bit in @buf. |
720 | * |
721 | * The bit positions 0 through @bits are valid positions in @buf. |
722 | */ |
723 | static int bitmap_pos_to_ord(const unsigned long *buf, int pos, int bits) |
724 | { |
725 | int i, ord; |
726 | |
727 | if (pos < 0 || pos >= bits || !test_bit(pos, buf)) |
728 | return -1; |
729 | |
730 | i = find_first_bit(buf, bits); |
731 | ord = 0; |
732 | while (i < pos) { |
733 | i = find_next_bit(buf, bits, i + 1); |
734 | ord++; |
735 | } |
736 | BUG_ON(i != pos); |
737 | |
738 | return ord; |
739 | } |
740 | |
741 | /** |
742 | * bitmap_ord_to_pos - find position of n-th set bit in bitmap |
743 | * @buf: pointer to bitmap |
744 | * @ord: ordinal bit position (n-th set bit, n >= 0) |
745 | * @bits: number of valid bit positions in @buf |
746 | * |
747 | * Map the ordinal offset of bit @ord in @buf to its position in @buf. |
748 | * Value of @ord should be in range 0 <= @ord < weight(buf), else |
749 | * results are undefined. |
750 | * |
751 | * If for example, just bits 4 through 7 are set in @buf, then @ord |
752 | * values 0 through 3 will get mapped to 4 through 7, respectively, |
753 | * and all other @ord values return undefined values. When @ord value 3 |
754 | * gets mapped to (returns) @pos value 7 in this example, that means |
755 | * that the 3rd set bit (starting with 0th) is at position 7 in @buf. |
756 | * |
757 | * The bit positions 0 through @bits are valid positions in @buf. |
758 | */ |
759 | static int bitmap_ord_to_pos(const unsigned long *buf, int ord, int bits) |
760 | { |
761 | int pos = 0; |
762 | |
763 | if (ord >= 0 && ord < bits) { |
764 | int i; |
765 | |
766 | for (i = find_first_bit(buf, bits); |
767 | i < bits && ord > 0; |
768 | i = find_next_bit(buf, bits, i + 1)) |
769 | ord--; |
770 | if (i < bits && ord == 0) |
771 | pos = i; |
772 | } |
773 | |
774 | return pos; |
775 | } |
776 | |
777 | /** |
778 | * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap |
779 | * @dst: remapped result |
780 | * @src: subset to be remapped |
781 | * @old: defines domain of map |
782 | * @new: defines range of map |
783 | * @bits: number of bits in each of these bitmaps |
784 | * |
785 | * Let @old and @new define a mapping of bit positions, such that |
786 | * whatever position is held by the n-th set bit in @old is mapped |
787 | * to the n-th set bit in @new. In the more general case, allowing |
788 | * for the possibility that the weight 'w' of @new is less than the |
789 | * weight of @old, map the position of the n-th set bit in @old to |
790 | * the position of the m-th set bit in @new, where m == n % w. |
791 | * |
792 | * If either of the @old and @new bitmaps are empty, or if @src and |
793 | * @dst point to the same location, then this routine copies @src |
794 | * to @dst. |
795 | * |
796 | * The positions of unset bits in @old are mapped to themselves |
797 | * (the identify map). |
798 | * |
799 | * Apply the above specified mapping to @src, placing the result in |
800 | * @dst, clearing any bits previously set in @dst. |
801 | * |
802 | * For example, lets say that @old has bits 4 through 7 set, and |
803 | * @new has bits 12 through 15 set. This defines the mapping of bit |
804 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other |
805 | * bit positions unchanged. So if say @src comes into this routine |
806 | * with bits 1, 5 and 7 set, then @dst should leave with bits 1, |
807 | * 13 and 15 set. |
808 | */ |
809 | void bitmap_remap(unsigned long *dst, const unsigned long *src, |
810 | const unsigned long *old, const unsigned long *new, |
811 | int bits) |
812 | { |
813 | int oldbit, w; |
814 | |
815 | if (dst == src) /* following doesn't handle inplace remaps */ |
816 | return; |
817 | bitmap_zero(dst, bits); |
818 | |
819 | w = bitmap_weight(new, bits); |
820 | for_each_set_bit(oldbit, src, bits) { |
821 | int n = bitmap_pos_to_ord(old, oldbit, bits); |
822 | |
823 | if (n < 0 || w == 0) |
824 | set_bit(oldbit, dst); /* identity map */ |
825 | else |
826 | set_bit(bitmap_ord_to_pos(new, n % w, bits), dst); |
827 | } |
828 | } |
829 | EXPORT_SYMBOL(bitmap_remap); |
830 | |
831 | /** |
832 | * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit |
833 | * @oldbit: bit position to be mapped |
834 | * @old: defines domain of map |
835 | * @new: defines range of map |
836 | * @bits: number of bits in each of these bitmaps |
837 | * |
838 | * Let @old and @new define a mapping of bit positions, such that |
839 | * whatever position is held by the n-th set bit in @old is mapped |
840 | * to the n-th set bit in @new. In the more general case, allowing |
841 | * for the possibility that the weight 'w' of @new is less than the |
842 | * weight of @old, map the position of the n-th set bit in @old to |
843 | * the position of the m-th set bit in @new, where m == n % w. |
844 | * |
845 | * The positions of unset bits in @old are mapped to themselves |
846 | * (the identify map). |
847 | * |
848 | * Apply the above specified mapping to bit position @oldbit, returning |
849 | * the new bit position. |
850 | * |
851 | * For example, lets say that @old has bits 4 through 7 set, and |
852 | * @new has bits 12 through 15 set. This defines the mapping of bit |
853 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other |
854 | * bit positions unchanged. So if say @oldbit is 5, then this routine |
855 | * returns 13. |
856 | */ |
857 | int bitmap_bitremap(int oldbit, const unsigned long *old, |
858 | const unsigned long *new, int bits) |
859 | { |
860 | int w = bitmap_weight(new, bits); |
861 | int n = bitmap_pos_to_ord(old, oldbit, bits); |
862 | if (n < 0 || w == 0) |
863 | return oldbit; |
864 | else |
865 | return bitmap_ord_to_pos(new, n % w, bits); |
866 | } |
867 | EXPORT_SYMBOL(bitmap_bitremap); |
868 | |
869 | /** |
870 | * bitmap_onto - translate one bitmap relative to another |
871 | * @dst: resulting translated bitmap |
872 | * @orig: original untranslated bitmap |
873 | * @relmap: bitmap relative to which translated |
874 | * @bits: number of bits in each of these bitmaps |
875 | * |
876 | * Set the n-th bit of @dst iff there exists some m such that the |
877 | * n-th bit of @relmap is set, the m-th bit of @orig is set, and |
878 | * the n-th bit of @relmap is also the m-th _set_ bit of @relmap. |
879 | * (If you understood the previous sentence the first time your |
880 | * read it, you're overqualified for your current job.) |
881 | * |
882 | * In other words, @orig is mapped onto (surjectively) @dst, |
883 | * using the the map { <n, m> | the n-th bit of @relmap is the |
884 | * m-th set bit of @relmap }. |
885 | * |
886 | * Any set bits in @orig above bit number W, where W is the |
887 | * weight of (number of set bits in) @relmap are mapped nowhere. |
888 | * In particular, if for all bits m set in @orig, m >= W, then |
889 | * @dst will end up empty. In situations where the possibility |
890 | * of such an empty result is not desired, one way to avoid it is |
891 | * to use the bitmap_fold() operator, below, to first fold the |
892 | * @orig bitmap over itself so that all its set bits x are in the |
893 | * range 0 <= x < W. The bitmap_fold() operator does this by |
894 | * setting the bit (m % W) in @dst, for each bit (m) set in @orig. |
895 | * |
896 | * Example [1] for bitmap_onto(): |
897 | * Let's say @relmap has bits 30-39 set, and @orig has bits |
898 | * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine, |
899 | * @dst will have bits 31, 33, 35, 37 and 39 set. |
900 | * |
901 | * When bit 0 is set in @orig, it means turn on the bit in |
902 | * @dst corresponding to whatever is the first bit (if any) |
903 | * that is turned on in @relmap. Since bit 0 was off in the |
904 | * above example, we leave off that bit (bit 30) in @dst. |
905 | * |
906 | * When bit 1 is set in @orig (as in the above example), it |
907 | * means turn on the bit in @dst corresponding to whatever |
908 | * is the second bit that is turned on in @relmap. The second |
909 | * bit in @relmap that was turned on in the above example was |
910 | * bit 31, so we turned on bit 31 in @dst. |
911 | * |
912 | * Similarly, we turned on bits 33, 35, 37 and 39 in @dst, |
913 | * because they were the 4th, 6th, 8th and 10th set bits |
914 | * set in @relmap, and the 4th, 6th, 8th and 10th bits of |
915 | * @orig (i.e. bits 3, 5, 7 and 9) were also set. |
916 | * |
917 | * When bit 11 is set in @orig, it means turn on the bit in |
918 | * @dst corresponding to whatever is the twelfth bit that is |
919 | * turned on in @relmap. In the above example, there were |
920 | * only ten bits turned on in @relmap (30..39), so that bit |
921 | * 11 was set in @orig had no affect on @dst. |
922 | * |
923 | * Example [2] for bitmap_fold() + bitmap_onto(): |
924 | * Let's say @relmap has these ten bits set: |
925 | * 40 41 42 43 45 48 53 61 74 95 |
926 | * (for the curious, that's 40 plus the first ten terms of the |
927 | * Fibonacci sequence.) |
928 | * |
929 | * Further lets say we use the following code, invoking |
930 | * bitmap_fold() then bitmap_onto, as suggested above to |
931 | * avoid the possitility of an empty @dst result: |
932 | * |
933 | * unsigned long *tmp; // a temporary bitmap's bits |
934 | * |
935 | * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits); |
936 | * bitmap_onto(dst, tmp, relmap, bits); |
937 | * |
938 | * Then this table shows what various values of @dst would be, for |
939 | * various @orig's. I list the zero-based positions of each set bit. |
940 | * The tmp column shows the intermediate result, as computed by |
941 | * using bitmap_fold() to fold the @orig bitmap modulo ten |
942 | * (the weight of @relmap). |
943 | * |
944 | * @orig tmp @dst |
945 | * 0 0 40 |
946 | * 1 1 41 |
947 | * 9 9 95 |
948 | * 10 0 40 (*) |
949 | * 1 3 5 7 1 3 5 7 41 43 48 61 |
950 | * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45 |
951 | * 0 9 18 27 0 9 8 7 40 61 74 95 |
952 | * 0 10 20 30 0 40 |
953 | * 0 11 22 33 0 1 2 3 40 41 42 43 |
954 | * 0 12 24 36 0 2 4 6 40 42 45 53 |
955 | * 78 102 211 1 2 8 41 42 74 (*) |
956 | * |
957 | * (*) For these marked lines, if we hadn't first done bitmap_fold() |
958 | * into tmp, then the @dst result would have been empty. |
959 | * |
960 | * If either of @orig or @relmap is empty (no set bits), then @dst |
961 | * will be returned empty. |
962 | * |
963 | * If (as explained above) the only set bits in @orig are in positions |
964 | * m where m >= W, (where W is the weight of @relmap) then @dst will |
965 | * once again be returned empty. |
966 | * |
967 | * All bits in @dst not set by the above rule are cleared. |
968 | */ |
969 | void bitmap_onto(unsigned long *dst, const unsigned long *orig, |
970 | const unsigned long *relmap, int bits) |
971 | { |
972 | int n, m; /* same meaning as in above comment */ |
973 | |
974 | if (dst == orig) /* following doesn't handle inplace mappings */ |
975 | return; |
976 | bitmap_zero(dst, bits); |
977 | |
978 | /* |
979 | * The following code is a more efficient, but less |
980 | * obvious, equivalent to the loop: |
981 | * for (m = 0; m < bitmap_weight(relmap, bits); m++) { |
982 | * n = bitmap_ord_to_pos(orig, m, bits); |
983 | * if (test_bit(m, orig)) |
984 | * set_bit(n, dst); |
985 | * } |
986 | */ |
987 | |
988 | m = 0; |
989 | for_each_set_bit(n, relmap, bits) { |
990 | /* m == bitmap_pos_to_ord(relmap, n, bits) */ |
991 | if (test_bit(m, orig)) |
992 | set_bit(n, dst); |
993 | m++; |
994 | } |
995 | } |
996 | EXPORT_SYMBOL(bitmap_onto); |
997 | |
998 | /** |
999 | * bitmap_fold - fold larger bitmap into smaller, modulo specified size |
1000 | * @dst: resulting smaller bitmap |
1001 | * @orig: original larger bitmap |
1002 | * @sz: specified size |
1003 | * @bits: number of bits in each of these bitmaps |
1004 | * |
1005 | * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst. |
1006 | * Clear all other bits in @dst. See further the comment and |
1007 | * Example [2] for bitmap_onto() for why and how to use this. |
1008 | */ |
1009 | void bitmap_fold(unsigned long *dst, const unsigned long *orig, |
1010 | int sz, int bits) |
1011 | { |
1012 | int oldbit; |
1013 | |
1014 | if (dst == orig) /* following doesn't handle inplace mappings */ |
1015 | return; |
1016 | bitmap_zero(dst, bits); |
1017 | |
1018 | for_each_set_bit(oldbit, orig, bits) |
1019 | set_bit(oldbit % sz, dst); |
1020 | } |
1021 | EXPORT_SYMBOL(bitmap_fold); |
1022 | |
1023 | /* |
1024 | * Common code for bitmap_*_region() routines. |
1025 | * bitmap: array of unsigned longs corresponding to the bitmap |
1026 | * pos: the beginning of the region |
1027 | * order: region size (log base 2 of number of bits) |
1028 | * reg_op: operation(s) to perform on that region of bitmap |
1029 | * |
1030 | * Can set, verify and/or release a region of bits in a bitmap, |
1031 | * depending on which combination of REG_OP_* flag bits is set. |
1032 | * |
1033 | * A region of a bitmap is a sequence of bits in the bitmap, of |
1034 | * some size '1 << order' (a power of two), aligned to that same |
1035 | * '1 << order' power of two. |
1036 | * |
1037 | * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits). |
1038 | * Returns 0 in all other cases and reg_ops. |
1039 | */ |
1040 | |
1041 | enum { |
1042 | REG_OP_ISFREE, /* true if region is all zero bits */ |
1043 | REG_OP_ALLOC, /* set all bits in region */ |
1044 | REG_OP_RELEASE, /* clear all bits in region */ |
1045 | }; |
1046 | |
1047 | static int __reg_op(unsigned long *bitmap, int pos, int order, int reg_op) |
1048 | { |
1049 | int nbits_reg; /* number of bits in region */ |
1050 | int index; /* index first long of region in bitmap */ |
1051 | int offset; /* bit offset region in bitmap[index] */ |
1052 | int nlongs_reg; /* num longs spanned by region in bitmap */ |
1053 | int nbitsinlong; /* num bits of region in each spanned long */ |
1054 | unsigned long mask; /* bitmask for one long of region */ |
1055 | int i; /* scans bitmap by longs */ |
1056 | int ret = 0; /* return value */ |
1057 | |
1058 | /* |
1059 | * Either nlongs_reg == 1 (for small orders that fit in one long) |
1060 | * or (offset == 0 && mask == ~0UL) (for larger multiword orders.) |
1061 | */ |
1062 | nbits_reg = 1 << order; |
1063 | index = pos / BITS_PER_LONG; |
1064 | offset = pos - (index * BITS_PER_LONG); |
1065 | nlongs_reg = BITS_TO_LONGS(nbits_reg); |
1066 | nbitsinlong = min(nbits_reg, BITS_PER_LONG); |
1067 | |
1068 | /* |
1069 | * Can't do "mask = (1UL << nbitsinlong) - 1", as that |
1070 | * overflows if nbitsinlong == BITS_PER_LONG. |
1071 | */ |
1072 | mask = (1UL << (nbitsinlong - 1)); |
1073 | mask += mask - 1; |
1074 | mask <<= offset; |
1075 | |
1076 | switch (reg_op) { |
1077 | case REG_OP_ISFREE: |
1078 | for (i = 0; i < nlongs_reg; i++) { |
1079 | if (bitmap[index + i] & mask) |
1080 | goto done; |
1081 | } |
1082 | ret = 1; /* all bits in region free (zero) */ |
1083 | break; |
1084 | |
1085 | case REG_OP_ALLOC: |
1086 | for (i = 0; i < nlongs_reg; i++) |
1087 | bitmap[index + i] |= mask; |
1088 | break; |
1089 | |
1090 | case REG_OP_RELEASE: |
1091 | for (i = 0; i < nlongs_reg; i++) |
1092 | bitmap[index + i] &= ~mask; |
1093 | break; |
1094 | } |
1095 | done: |
1096 | return ret; |
1097 | } |
1098 | |
1099 | /** |
1100 | * bitmap_find_free_region - find a contiguous aligned mem region |
1101 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1102 | * @bits: number of bits in the bitmap |
1103 | * @order: region size (log base 2 of number of bits) to find |
1104 | * |
1105 | * Find a region of free (zero) bits in a @bitmap of @bits bits and |
1106 | * allocate them (set them to one). Only consider regions of length |
1107 | * a power (@order) of two, aligned to that power of two, which |
1108 | * makes the search algorithm much faster. |
1109 | * |
1110 | * Return the bit offset in bitmap of the allocated region, |
1111 | * or -errno on failure. |
1112 | */ |
1113 | int bitmap_find_free_region(unsigned long *bitmap, int bits, int order) |
1114 | { |
1115 | int pos, end; /* scans bitmap by regions of size order */ |
1116 | |
1117 | for (pos = 0 ; (end = pos + (1 << order)) <= bits; pos = end) { |
1118 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
1119 | continue; |
1120 | __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
1121 | return pos; |
1122 | } |
1123 | return -ENOMEM; |
1124 | } |
1125 | EXPORT_SYMBOL(bitmap_find_free_region); |
1126 | |
1127 | /** |
1128 | * bitmap_release_region - release allocated bitmap region |
1129 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1130 | * @pos: beginning of bit region to release |
1131 | * @order: region size (log base 2 of number of bits) to release |
1132 | * |
1133 | * This is the complement to __bitmap_find_free_region() and releases |
1134 | * the found region (by clearing it in the bitmap). |
1135 | * |
1136 | * No return value. |
1137 | */ |
1138 | void bitmap_release_region(unsigned long *bitmap, int pos, int order) |
1139 | { |
1140 | __reg_op(bitmap, pos, order, REG_OP_RELEASE); |
1141 | } |
1142 | EXPORT_SYMBOL(bitmap_release_region); |
1143 | |
1144 | /** |
1145 | * bitmap_allocate_region - allocate bitmap region |
1146 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1147 | * @pos: beginning of bit region to allocate |
1148 | * @order: region size (log base 2 of number of bits) to allocate |
1149 | * |
1150 | * Allocate (set bits in) a specified region of a bitmap. |
1151 | * |
1152 | * Return 0 on success, or %-EBUSY if specified region wasn't |
1153 | * free (not all bits were zero). |
1154 | */ |
1155 | int bitmap_allocate_region(unsigned long *bitmap, int pos, int order) |
1156 | { |
1157 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
1158 | return -EBUSY; |
1159 | __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
1160 | return 0; |
1161 | } |
1162 | EXPORT_SYMBOL(bitmap_allocate_region); |
1163 | |
1164 | /** |
1165 | * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. |
1166 | * @dst: destination buffer |
1167 | * @src: bitmap to copy |
1168 | * @nbits: number of bits in the bitmap |
1169 | * |
1170 | * Require nbits % BITS_PER_LONG == 0. |
1171 | */ |
1172 | void bitmap_copy_le(void *dst, const unsigned long *src, int nbits) |
1173 | { |
1174 | unsigned long *d = dst; |
1175 | int i; |
1176 | |
1177 | for (i = 0; i < nbits/BITS_PER_LONG; i++) { |
1178 | if (BITS_PER_LONG == 64) |
1179 | d[i] = cpu_to_le64(src[i]); |
1180 | else |
1181 | d[i] = cpu_to_le32(src[i]); |
1182 | } |
1183 | } |
1184 | EXPORT_SYMBOL(bitmap_copy_le); |
1185 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
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jz-2.6.39
jz-3.0
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jz-3.11
jz-3.12
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jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9