1 // SPDX-License-Identifier: GPL-2.0-only 1 // SPDX-License-Identifier: GPL-2.0-only
2 /* 2 /*
3 * lib/bitmap.c 3 * lib/bitmap.c
4 * Helper functions for bitmap.h. 4 * Helper functions for bitmap.h.
5 */ 5 */
6 !! 6 #include <linux/export.h>
>> 7 #include <linux/thread_info.h>
>> 8 #include <linux/ctype.h>
>> 9 #include <linux/errno.h>
7 #include <linux/bitmap.h> 10 #include <linux/bitmap.h>
8 #include <linux/bitops.h> 11 #include <linux/bitops.h>
9 #include <linux/ctype.h> !! 12 #include <linux/bug.h>
10 #include <linux/device.h> !! 13 #include <linux/kernel.h>
11 #include <linux/export.h> !! 14 #include <linux/mm.h>
12 #include <linux/slab.h> 15 #include <linux/slab.h>
>> 16 #include <linux/string.h>
>> 17 #include <linux/uaccess.h>
>> 18
>> 19 #include <asm/page.h>
>> 20
>> 21 #include "kstrtox.h"
13 22
14 /** 23 /**
15 * DOC: bitmap introduction 24 * DOC: bitmap introduction
16 * 25 *
17 * bitmaps provide an array of bits, implement !! 26 * bitmaps provide an array of bits, implemented using an an
18 * array of unsigned longs. The number of val 27 * array of unsigned longs. The number of valid bits in a
19 * given bitmap does _not_ need to be an exact 28 * given bitmap does _not_ need to be an exact multiple of
20 * BITS_PER_LONG. 29 * BITS_PER_LONG.
21 * 30 *
22 * The possible unused bits in the last, parti 31 * The possible unused bits in the last, partially used word
23 * of a bitmap are 'don't care'. The implemen 32 * of a bitmap are 'don't care'. The implementation makes
24 * no particular effort to keep them zero. It 33 * no particular effort to keep them zero. It ensures that
25 * their value will not affect the results of 34 * their value will not affect the results of any operation.
26 * The bitmap operations that return Boolean ( 35 * The bitmap operations that return Boolean (bitmap_empty,
27 * for example) or scalar (bitmap_weight, for 36 * for example) or scalar (bitmap_weight, for example) results
28 * carefully filter out these unused bits from 37 * carefully filter out these unused bits from impacting their
29 * results. 38 * results.
30 * 39 *
31 * The byte ordering of bitmaps is more natura 40 * The byte ordering of bitmaps is more natural on little
32 * endian architectures. See the big-endian h 41 * endian architectures. See the big-endian headers
33 * include/asm-ppc64/bitops.h and include/asm- 42 * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h
34 * for the best explanations of this ordering. 43 * for the best explanations of this ordering.
35 */ 44 */
36 45
37 bool __bitmap_equal(const unsigned long *bitma !! 46 int __bitmap_equal(const unsigned long *bitmap1,
38 const unsigned long *bitma !! 47 const unsigned long *bitmap2, unsigned int bits)
39 { 48 {
40 unsigned int k, lim = bits/BITS_PER_LO 49 unsigned int k, lim = bits/BITS_PER_LONG;
41 for (k = 0; k < lim; ++k) 50 for (k = 0; k < lim; ++k)
42 if (bitmap1[k] != bitmap2[k]) 51 if (bitmap1[k] != bitmap2[k])
43 return false; !! 52 return 0;
44 53
45 if (bits % BITS_PER_LONG) 54 if (bits % BITS_PER_LONG)
46 if ((bitmap1[k] ^ bitmap2[k]) 55 if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
47 return false; !! 56 return 0;
48 57
49 return true; !! 58 return 1;
50 } 59 }
51 EXPORT_SYMBOL(__bitmap_equal); 60 EXPORT_SYMBOL(__bitmap_equal);
52 61
53 bool __bitmap_or_equal(const unsigned long *bi <<
54 const unsigned long *bi <<
55 const unsigned long *bi <<
56 unsigned int bits) <<
57 { <<
58 unsigned int k, lim = bits / BITS_PER_ <<
59 unsigned long tmp; <<
60 <<
61 for (k = 0; k < lim; ++k) { <<
62 if ((bitmap1[k] | bitmap2[k]) <<
63 return false; <<
64 } <<
65 <<
66 if (!(bits % BITS_PER_LONG)) <<
67 return true; <<
68 <<
69 tmp = (bitmap1[k] | bitmap2[k]) ^ bitm <<
70 return (tmp & BITMAP_LAST_WORD_MASK(bi <<
71 } <<
72 <<
73 void __bitmap_complement(unsigned long *dst, c 62 void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits)
74 { 63 {
75 unsigned int k, lim = BITS_TO_LONGS(bi 64 unsigned int k, lim = BITS_TO_LONGS(bits);
76 for (k = 0; k < lim; ++k) 65 for (k = 0; k < lim; ++k)
77 dst[k] = ~src[k]; 66 dst[k] = ~src[k];
78 } 67 }
79 EXPORT_SYMBOL(__bitmap_complement); 68 EXPORT_SYMBOL(__bitmap_complement);
80 69
81 /** 70 /**
82 * __bitmap_shift_right - logical right shift 71 * __bitmap_shift_right - logical right shift of the bits in a bitmap
83 * @dst : destination bitmap 72 * @dst : destination bitmap
84 * @src : source bitmap 73 * @src : source bitmap
85 * @shift : shift by this many bits 74 * @shift : shift by this many bits
86 * @nbits : bitmap size, in bits 75 * @nbits : bitmap size, in bits
87 * 76 *
88 * Shifting right (dividing) means moving bits 77 * Shifting right (dividing) means moving bits in the MS -> LS bit
89 * direction. Zeros are fed into the vacated 78 * direction. Zeros are fed into the vacated MS positions and the
90 * LS bits shifted off the bottom are lost. 79 * LS bits shifted off the bottom are lost.
91 */ 80 */
92 void __bitmap_shift_right(unsigned long *dst, 81 void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
93 unsigned shift, unsign 82 unsigned shift, unsigned nbits)
94 { 83 {
95 unsigned k, lim = BITS_TO_LONGS(nbits) 84 unsigned k, lim = BITS_TO_LONGS(nbits);
96 unsigned off = shift/BITS_PER_LONG, re 85 unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG;
97 unsigned long mask = BITMAP_LAST_WORD_ 86 unsigned long mask = BITMAP_LAST_WORD_MASK(nbits);
98 for (k = 0; off + k < lim; ++k) { 87 for (k = 0; off + k < lim; ++k) {
99 unsigned long upper, lower; 88 unsigned long upper, lower;
100 89
101 /* 90 /*
102 * If shift is not word aligne 91 * If shift is not word aligned, take lower rem bits of
103 * word above and make them th 92 * word above and make them the top rem bits of result.
104 */ 93 */
105 if (!rem || off + k + 1 >= lim 94 if (!rem || off + k + 1 >= lim)
106 upper = 0; 95 upper = 0;
107 else { 96 else {
108 upper = src[off + k + 97 upper = src[off + k + 1];
109 if (off + k + 1 == lim 98 if (off + k + 1 == lim - 1)
110 upper &= mask; 99 upper &= mask;
111 upper <<= (BITS_PER_LO 100 upper <<= (BITS_PER_LONG - rem);
112 } 101 }
113 lower = src[off + k]; 102 lower = src[off + k];
114 if (off + k == lim - 1) 103 if (off + k == lim - 1)
115 lower &= mask; 104 lower &= mask;
116 lower >>= rem; 105 lower >>= rem;
117 dst[k] = lower | upper; 106 dst[k] = lower | upper;
118 } 107 }
119 if (off) 108 if (off)
120 memset(&dst[lim - off], 0, off 109 memset(&dst[lim - off], 0, off*sizeof(unsigned long));
121 } 110 }
122 EXPORT_SYMBOL(__bitmap_shift_right); 111 EXPORT_SYMBOL(__bitmap_shift_right);
123 112
124 113
125 /** 114 /**
126 * __bitmap_shift_left - logical left shift of 115 * __bitmap_shift_left - logical left shift of the bits in a bitmap
127 * @dst : destination bitmap 116 * @dst : destination bitmap
128 * @src : source bitmap 117 * @src : source bitmap
129 * @shift : shift by this many bits 118 * @shift : shift by this many bits
130 * @nbits : bitmap size, in bits 119 * @nbits : bitmap size, in bits
131 * 120 *
132 * Shifting left (multiplying) means moving bi 121 * Shifting left (multiplying) means moving bits in the LS -> MS
133 * direction. Zeros are fed into the vacated 122 * direction. Zeros are fed into the vacated LS bit positions
134 * and those MS bits shifted off the top are l 123 * and those MS bits shifted off the top are lost.
135 */ 124 */
136 125
137 void __bitmap_shift_left(unsigned long *dst, c 126 void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
138 unsigned int shift, un 127 unsigned int shift, unsigned int nbits)
139 { 128 {
140 int k; 129 int k;
141 unsigned int lim = BITS_TO_LONGS(nbits 130 unsigned int lim = BITS_TO_LONGS(nbits);
142 unsigned int off = shift/BITS_PER_LONG 131 unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG;
143 for (k = lim - off - 1; k >= 0; --k) { 132 for (k = lim - off - 1; k >= 0; --k) {
144 unsigned long upper, lower; 133 unsigned long upper, lower;
145 134
146 /* 135 /*
147 * If shift is not word aligne 136 * If shift is not word aligned, take upper rem bits of
148 * word below and make them th 137 * word below and make them the bottom rem bits of result.
149 */ 138 */
150 if (rem && k > 0) 139 if (rem && k > 0)
151 lower = src[k - 1] >> 140 lower = src[k - 1] >> (BITS_PER_LONG - rem);
152 else 141 else
153 lower = 0; 142 lower = 0;
154 upper = src[k] << rem; 143 upper = src[k] << rem;
155 dst[k + off] = lower | upper; 144 dst[k + off] = lower | upper;
156 } 145 }
157 if (off) 146 if (off)
158 memset(dst, 0, off*sizeof(unsi 147 memset(dst, 0, off*sizeof(unsigned long));
159 } 148 }
160 EXPORT_SYMBOL(__bitmap_shift_left); 149 EXPORT_SYMBOL(__bitmap_shift_left);
161 150
162 /** !! 151 int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
163 * bitmap_cut() - remove bit region from bitma <<
164 * @dst: destination bitmap, might overlap wit <<
165 * @src: source bitmap <<
166 * @first: start bit of region to be removed <<
167 * @cut: number of bits to remove <<
168 * @nbits: bitmap size, in bits <<
169 * <<
170 * Set the n-th bit of @dst iff the n-th bit o <<
171 * n is less than @first, or the m-th bit of @ <<
172 * m such that @first <= n < nbits, and m = n <<
173 * <<
174 * In pictures, example for a big-endian 32-bi <<
175 * <<
176 * The @src bitmap is:: <<
177 * <<
178 * 31 63 <<
179 * | | <<
180 * 10000000 11000001 11110010 00010101 1000 <<
181 * | | | <<
182 * 16 14 0 <<
183 * <<
184 * if @cut is 3, and @first is 14, bits 14-16 <<
185 * <<
186 * 31 63 <<
187 * | | <<
188 * 10110000 00011000 00110010 00010101 0001 <<
189 * | | <<
190 * 14 (bit 17 0 <<
191 * from @src) <<
192 * <<
193 * Note that @dst and @src might overlap parti <<
194 * <<
195 * This is implemented in the obvious way, wit <<
196 * step for each moved bit. Optimisation is le <<
197 * for the compiler. <<
198 */ <<
199 void bitmap_cut(unsigned long *dst, const unsi <<
200 unsigned int first, unsigned i <<
201 { <<
202 unsigned int len = BITS_TO_LONGS(nbits <<
203 unsigned long keep = 0, carry; <<
204 int i; <<
205 <<
206 if (first % BITS_PER_LONG) { <<
207 keep = src[first / BITS_PER_LO <<
208 (~0UL >> (BITS_PER_LONG <<
209 } <<
210 <<
211 memmove(dst, src, len * sizeof(*dst)); <<
212 <<
213 while (cut--) { <<
214 for (i = first / BITS_PER_LONG <<
215 if (i < len - 1) <<
216 carry = dst[i <<
217 else <<
218 carry = 0; <<
219 <<
220 dst[i] = (dst[i] >> 1) <<
221 } <<
222 } <<
223 <<
224 dst[first / BITS_PER_LONG] &= ~0UL << <<
225 dst[first / BITS_PER_LONG] |= keep; <<
226 } <<
227 EXPORT_SYMBOL(bitmap_cut); <<
228 <<
229 bool __bitmap_and(unsigned long *dst, const un <<
230 const unsigned 152 const unsigned long *bitmap2, unsigned int bits)
231 { 153 {
232 unsigned int k; 154 unsigned int k;
233 unsigned int lim = bits/BITS_PER_LONG; 155 unsigned int lim = bits/BITS_PER_LONG;
234 unsigned long result = 0; 156 unsigned long result = 0;
235 157
236 for (k = 0; k < lim; k++) 158 for (k = 0; k < lim; k++)
237 result |= (dst[k] = bitmap1[k] 159 result |= (dst[k] = bitmap1[k] & bitmap2[k]);
238 if (bits % BITS_PER_LONG) 160 if (bits % BITS_PER_LONG)
239 result |= (dst[k] = bitmap1[k] 161 result |= (dst[k] = bitmap1[k] & bitmap2[k] &
240 BITMAP_LAST_WORD_MA 162 BITMAP_LAST_WORD_MASK(bits));
241 return result != 0; 163 return result != 0;
242 } 164 }
243 EXPORT_SYMBOL(__bitmap_and); 165 EXPORT_SYMBOL(__bitmap_and);
244 166
245 void __bitmap_or(unsigned long *dst, const uns 167 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
246 const unsigned 168 const unsigned long *bitmap2, unsigned int bits)
247 { 169 {
248 unsigned int k; 170 unsigned int k;
249 unsigned int nr = BITS_TO_LONGS(bits); 171 unsigned int nr = BITS_TO_LONGS(bits);
250 172
251 for (k = 0; k < nr; k++) 173 for (k = 0; k < nr; k++)
252 dst[k] = bitmap1[k] | bitmap2[ 174 dst[k] = bitmap1[k] | bitmap2[k];
253 } 175 }
254 EXPORT_SYMBOL(__bitmap_or); 176 EXPORT_SYMBOL(__bitmap_or);
255 177
256 void __bitmap_xor(unsigned long *dst, const un 178 void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
257 const unsigned 179 const unsigned long *bitmap2, unsigned int bits)
258 { 180 {
259 unsigned int k; 181 unsigned int k;
260 unsigned int nr = BITS_TO_LONGS(bits); 182 unsigned int nr = BITS_TO_LONGS(bits);
261 183
262 for (k = 0; k < nr; k++) 184 for (k = 0; k < nr; k++)
263 dst[k] = bitmap1[k] ^ bitmap2[ 185 dst[k] = bitmap1[k] ^ bitmap2[k];
264 } 186 }
265 EXPORT_SYMBOL(__bitmap_xor); 187 EXPORT_SYMBOL(__bitmap_xor);
266 188
267 bool __bitmap_andnot(unsigned long *dst, const !! 189 int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
268 const unsigned 190 const unsigned long *bitmap2, unsigned int bits)
269 { 191 {
270 unsigned int k; 192 unsigned int k;
271 unsigned int lim = bits/BITS_PER_LONG; 193 unsigned int lim = bits/BITS_PER_LONG;
272 unsigned long result = 0; 194 unsigned long result = 0;
273 195
274 for (k = 0; k < lim; k++) 196 for (k = 0; k < lim; k++)
275 result |= (dst[k] = bitmap1[k] 197 result |= (dst[k] = bitmap1[k] & ~bitmap2[k]);
276 if (bits % BITS_PER_LONG) 198 if (bits % BITS_PER_LONG)
277 result |= (dst[k] = bitmap1[k] 199 result |= (dst[k] = bitmap1[k] & ~bitmap2[k] &
278 BITMAP_LAST_WORD_MA 200 BITMAP_LAST_WORD_MASK(bits));
279 return result != 0; 201 return result != 0;
280 } 202 }
281 EXPORT_SYMBOL(__bitmap_andnot); 203 EXPORT_SYMBOL(__bitmap_andnot);
282 204
283 void __bitmap_replace(unsigned long *dst, !! 205 int __bitmap_intersects(const unsigned long *bitmap1,
284 const unsigned long *old !! 206 const unsigned long *bitmap2, unsigned int bits)
285 const unsigned long *mas <<
286 { <<
287 unsigned int k; <<
288 unsigned int nr = BITS_TO_LONGS(nbits) <<
289 <<
290 for (k = 0; k < nr; k++) <<
291 dst[k] = (old[k] & ~mask[k]) | <<
292 } <<
293 EXPORT_SYMBOL(__bitmap_replace); <<
294 <<
295 bool __bitmap_intersects(const unsigned long * <<
296 const unsigned long * <<
297 { 207 {
298 unsigned int k, lim = bits/BITS_PER_LO 208 unsigned int k, lim = bits/BITS_PER_LONG;
299 for (k = 0; k < lim; ++k) 209 for (k = 0; k < lim; ++k)
300 if (bitmap1[k] & bitmap2[k]) 210 if (bitmap1[k] & bitmap2[k])
301 return true; !! 211 return 1;
302 212
303 if (bits % BITS_PER_LONG) 213 if (bits % BITS_PER_LONG)
304 if ((bitmap1[k] & bitmap2[k]) 214 if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
305 return true; !! 215 return 1;
306 return false; !! 216 return 0;
307 } 217 }
308 EXPORT_SYMBOL(__bitmap_intersects); 218 EXPORT_SYMBOL(__bitmap_intersects);
309 219
310 bool __bitmap_subset(const unsigned long *bitm !! 220 int __bitmap_subset(const unsigned long *bitmap1,
311 const unsigned long *bitm !! 221 const unsigned long *bitmap2, unsigned int bits)
312 { 222 {
313 unsigned int k, lim = bits/BITS_PER_LO 223 unsigned int k, lim = bits/BITS_PER_LONG;
314 for (k = 0; k < lim; ++k) 224 for (k = 0; k < lim; ++k)
315 if (bitmap1[k] & ~bitmap2[k]) 225 if (bitmap1[k] & ~bitmap2[k])
316 return false; !! 226 return 0;
317 227
318 if (bits % BITS_PER_LONG) 228 if (bits % BITS_PER_LONG)
319 if ((bitmap1[k] & ~bitmap2[k]) 229 if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
320 return false; !! 230 return 0;
321 return true; !! 231 return 1;
322 } 232 }
323 EXPORT_SYMBOL(__bitmap_subset); 233 EXPORT_SYMBOL(__bitmap_subset);
324 234
325 #define BITMAP_WEIGHT(FETCH, bits) \ !! 235 int __bitmap_weight(const unsigned long *bitmap, unsigned int bits)
326 ({ <<
327 unsigned int __bits = (bits), idx, w = <<
328 <<
329 for (idx = 0; idx < __bits / BITS_PER_ <<
330 w += hweight_long(FETCH); <<
331 <<
332 if (__bits % BITS_PER_LONG) <<
333 w += hweight_long((FETCH) & BI <<
334 <<
335 w; <<
336 }) <<
337 <<
338 unsigned int __bitmap_weight(const unsigned lo <<
339 { 236 {
340 return BITMAP_WEIGHT(bitmap[idx], bits !! 237 unsigned int k, lim = bits/BITS_PER_LONG;
341 } !! 238 int w = 0;
342 EXPORT_SYMBOL(__bitmap_weight); <<
343 239
344 unsigned int __bitmap_weight_and(const unsigne !! 240 for (k = 0; k < lim; k++)
345 const unsigned !! 241 w += hweight_long(bitmap[k]);
346 { <<
347 return BITMAP_WEIGHT(bitmap1[idx] & bi <<
348 } <<
349 EXPORT_SYMBOL(__bitmap_weight_and); <<
350 242
351 unsigned int __bitmap_weight_andnot(const unsi !! 243 if (bits % BITS_PER_LONG)
352 const unsigned !! 244 w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
353 { !! 245
354 return BITMAP_WEIGHT(bitmap1[idx] & ~b !! 246 return w;
355 } 247 }
356 EXPORT_SYMBOL(__bitmap_weight_andnot); !! 248 EXPORT_SYMBOL(__bitmap_weight);
357 249
358 void __bitmap_set(unsigned long *map, unsigned 250 void __bitmap_set(unsigned long *map, unsigned int start, int len)
359 { 251 {
360 unsigned long *p = map + BIT_WORD(star 252 unsigned long *p = map + BIT_WORD(start);
361 const unsigned int size = start + len; 253 const unsigned int size = start + len;
362 int bits_to_set = BITS_PER_LONG - (sta 254 int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
363 unsigned long mask_to_set = BITMAP_FIR 255 unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
364 256
365 while (len - bits_to_set >= 0) { 257 while (len - bits_to_set >= 0) {
366 *p |= mask_to_set; 258 *p |= mask_to_set;
367 len -= bits_to_set; 259 len -= bits_to_set;
368 bits_to_set = BITS_PER_LONG; 260 bits_to_set = BITS_PER_LONG;
369 mask_to_set = ~0UL; 261 mask_to_set = ~0UL;
370 p++; 262 p++;
371 } 263 }
372 if (len) { 264 if (len) {
373 mask_to_set &= BITMAP_LAST_WOR 265 mask_to_set &= BITMAP_LAST_WORD_MASK(size);
374 *p |= mask_to_set; 266 *p |= mask_to_set;
375 } 267 }
376 } 268 }
377 EXPORT_SYMBOL(__bitmap_set); 269 EXPORT_SYMBOL(__bitmap_set);
378 270
379 void __bitmap_clear(unsigned long *map, unsign 271 void __bitmap_clear(unsigned long *map, unsigned int start, int len)
380 { 272 {
381 unsigned long *p = map + BIT_WORD(star 273 unsigned long *p = map + BIT_WORD(start);
382 const unsigned int size = start + len; 274 const unsigned int size = start + len;
383 int bits_to_clear = BITS_PER_LONG - (s 275 int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
384 unsigned long mask_to_clear = BITMAP_F 276 unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
385 277
386 while (len - bits_to_clear >= 0) { 278 while (len - bits_to_clear >= 0) {
387 *p &= ~mask_to_clear; 279 *p &= ~mask_to_clear;
388 len -= bits_to_clear; 280 len -= bits_to_clear;
389 bits_to_clear = BITS_PER_LONG; 281 bits_to_clear = BITS_PER_LONG;
390 mask_to_clear = ~0UL; 282 mask_to_clear = ~0UL;
391 p++; 283 p++;
392 } 284 }
393 if (len) { 285 if (len) {
394 mask_to_clear &= BITMAP_LAST_W 286 mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
395 *p &= ~mask_to_clear; 287 *p &= ~mask_to_clear;
396 } 288 }
397 } 289 }
398 EXPORT_SYMBOL(__bitmap_clear); 290 EXPORT_SYMBOL(__bitmap_clear);
399 291
400 /** 292 /**
401 * bitmap_find_next_zero_area_off - find a con 293 * bitmap_find_next_zero_area_off - find a contiguous aligned zero area
402 * @map: The address to base the search on 294 * @map: The address to base the search on
403 * @size: The bitmap size in bits 295 * @size: The bitmap size in bits
404 * @start: The bitnumber to start searching at 296 * @start: The bitnumber to start searching at
405 * @nr: The number of zeroed bits we're lookin 297 * @nr: The number of zeroed bits we're looking for
406 * @align_mask: Alignment mask for zero area 298 * @align_mask: Alignment mask for zero area
407 * @align_offset: Alignment offset for zero ar 299 * @align_offset: Alignment offset for zero area.
408 * 300 *
409 * The @align_mask should be one less than a p 301 * The @align_mask should be one less than a power of 2; the effect is that
410 * the bit offset of all zero areas this funct 302 * the bit offset of all zero areas this function finds plus @align_offset
411 * is multiple of that power of 2. 303 * is multiple of that power of 2.
412 */ 304 */
413 unsigned long bitmap_find_next_zero_area_off(u 305 unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
414 u 306 unsigned long size,
415 u 307 unsigned long start,
416 u 308 unsigned int nr,
417 u 309 unsigned long align_mask,
418 u 310 unsigned long align_offset)
419 { 311 {
420 unsigned long index, end, i; 312 unsigned long index, end, i;
421 again: 313 again:
422 index = find_next_zero_bit(map, size, 314 index = find_next_zero_bit(map, size, start);
423 315
424 /* Align allocation */ 316 /* Align allocation */
425 index = __ALIGN_MASK(index + align_off 317 index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset;
426 318
427 end = index + nr; 319 end = index + nr;
428 if (end > size) 320 if (end > size)
429 return end; 321 return end;
430 i = find_next_bit(map, end, index); 322 i = find_next_bit(map, end, index);
431 if (i < end) { 323 if (i < end) {
432 start = i + 1; 324 start = i + 1;
433 goto again; 325 goto again;
434 } 326 }
435 return index; 327 return index;
436 } 328 }
437 EXPORT_SYMBOL(bitmap_find_next_zero_area_off); 329 EXPORT_SYMBOL(bitmap_find_next_zero_area_off);
438 330
>> 331 /*
>> 332 * Bitmap printing & parsing functions: first version by Nadia Yvette Chambers,
>> 333 * second version by Paul Jackson, third by Joe Korty.
>> 334 */
>> 335
>> 336 #define CHUNKSZ 32
>> 337 #define nbits_to_hold_value(val) fls(val)
>> 338 #define BASEDEC 10 /* fancier cpuset lists input in decimal */
>> 339
>> 340 /**
>> 341 * __bitmap_parse - convert an ASCII hex string into a bitmap.
>> 342 * @buf: pointer to buffer containing string.
>> 343 * @buflen: buffer size in bytes. If string is smaller than this
>> 344 * then it must be terminated with a \0.
>> 345 * @is_user: location of buffer, 0 indicates kernel space
>> 346 * @maskp: pointer to bitmap array that will contain result.
>> 347 * @nmaskbits: size of bitmap, in bits.
>> 348 *
>> 349 * Commas group hex digits into chunks. Each chunk defines exactly 32
>> 350 * bits of the resultant bitmask. No chunk may specify a value larger
>> 351 * than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value
>> 352 * then leading 0-bits are prepended. %-EINVAL is returned for illegal
>> 353 * characters and for grouping errors such as "1,,5", ",44", "," and "".
>> 354 * Leading and trailing whitespace accepted, but not embedded whitespace.
>> 355 */
>> 356 int __bitmap_parse(const char *buf, unsigned int buflen,
>> 357 int is_user, unsigned long *maskp,
>> 358 int nmaskbits)
>> 359 {
>> 360 int c, old_c, totaldigits, ndigits, nchunks, nbits;
>> 361 u32 chunk;
>> 362 const char __user __force *ubuf = (const char __user __force *)buf;
>> 363
>> 364 bitmap_zero(maskp, nmaskbits);
>> 365
>> 366 nchunks = nbits = totaldigits = c = 0;
>> 367 do {
>> 368 chunk = 0;
>> 369 ndigits = totaldigits;
>> 370
>> 371 /* Get the next chunk of the bitmap */
>> 372 while (buflen) {
>> 373 old_c = c;
>> 374 if (is_user) {
>> 375 if (__get_user(c, ubuf++))
>> 376 return -EFAULT;
>> 377 }
>> 378 else
>> 379 c = *buf++;
>> 380 buflen--;
>> 381 if (isspace(c))
>> 382 continue;
>> 383
>> 384 /*
>> 385 * If the last character was a space and the current
>> 386 * character isn't '\0', we've got embedded whitespace.
>> 387 * This is a no-no, so throw an error.
>> 388 */
>> 389 if (totaldigits && c && isspace(old_c))
>> 390 return -EINVAL;
>> 391
>> 392 /* A '\0' or a ',' signal the end of the chunk */
>> 393 if (c == '\0' || c == ',')
>> 394 break;
>> 395
>> 396 if (!isxdigit(c))
>> 397 return -EINVAL;
>> 398
>> 399 /*
>> 400 * Make sure there are at least 4 free bits in 'chunk'.
>> 401 * If not, this hexdigit will overflow 'chunk', so
>> 402 * throw an error.
>> 403 */
>> 404 if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1))
>> 405 return -EOVERFLOW;
>> 406
>> 407 chunk = (chunk << 4) | hex_to_bin(c);
>> 408 totaldigits++;
>> 409 }
>> 410 if (ndigits == totaldigits)
>> 411 return -EINVAL;
>> 412 if (nchunks == 0 && chunk == 0)
>> 413 continue;
>> 414
>> 415 __bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits);
>> 416 *maskp |= chunk;
>> 417 nchunks++;
>> 418 nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ;
>> 419 if (nbits > nmaskbits)
>> 420 return -EOVERFLOW;
>> 421 } while (buflen && c == ',');
>> 422
>> 423 return 0;
>> 424 }
>> 425 EXPORT_SYMBOL(__bitmap_parse);
>> 426
>> 427 /**
>> 428 * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap
>> 429 *
>> 430 * @ubuf: pointer to user buffer containing string.
>> 431 * @ulen: buffer size in bytes. If string is smaller than this
>> 432 * then it must be terminated with a \0.
>> 433 * @maskp: pointer to bitmap array that will contain result.
>> 434 * @nmaskbits: size of bitmap, in bits.
>> 435 *
>> 436 * Wrapper for __bitmap_parse(), providing it with user buffer.
>> 437 *
>> 438 * We cannot have this as an inline function in bitmap.h because it needs
>> 439 * linux/uaccess.h to get the access_ok() declaration and this causes
>> 440 * cyclic dependencies.
>> 441 */
>> 442 int bitmap_parse_user(const char __user *ubuf,
>> 443 unsigned int ulen, unsigned long *maskp,
>> 444 int nmaskbits)
>> 445 {
>> 446 if (!access_ok(ubuf, ulen))
>> 447 return -EFAULT;
>> 448 return __bitmap_parse((const char __force *)ubuf,
>> 449 ulen, 1, maskp, nmaskbits);
>> 450
>> 451 }
>> 452 EXPORT_SYMBOL(bitmap_parse_user);
>> 453
>> 454 /**
>> 455 * bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string
>> 456 * @list: indicates whether the bitmap must be list
>> 457 * @buf: page aligned buffer into which string is placed
>> 458 * @maskp: pointer to bitmap to convert
>> 459 * @nmaskbits: size of bitmap, in bits
>> 460 *
>> 461 * Output format is a comma-separated list of decimal numbers and
>> 462 * ranges if list is specified or hex digits grouped into comma-separated
>> 463 * sets of 8 digits/set. Returns the number of characters written to buf.
>> 464 *
>> 465 * It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned
>> 466 * area and that sufficient storage remains at @buf to accommodate the
>> 467 * bitmap_print_to_pagebuf() output. Returns the number of characters
>> 468 * actually printed to @buf, excluding terminating '\0'.
>> 469 */
>> 470 int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
>> 471 int nmaskbits)
>> 472 {
>> 473 ptrdiff_t len = PAGE_SIZE - offset_in_page(buf);
>> 474
>> 475 return list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) :
>> 476 scnprintf(buf, len, "%*pb\n", nmaskbits, maskp);
>> 477 }
>> 478 EXPORT_SYMBOL(bitmap_print_to_pagebuf);
>> 479
>> 480 /*
>> 481 * Region 9-38:4/10 describes the following bitmap structure:
>> 482 * 0 9 12 18 38
>> 483 * .........****......****......****......
>> 484 * ^ ^ ^ ^
>> 485 * start off group_len end
>> 486 */
>> 487 struct region {
>> 488 unsigned int start;
>> 489 unsigned int off;
>> 490 unsigned int group_len;
>> 491 unsigned int end;
>> 492 };
>> 493
>> 494 static int bitmap_set_region(const struct region *r,
>> 495 unsigned long *bitmap, int nbits)
>> 496 {
>> 497 unsigned int start;
>> 498
>> 499 if (r->end >= nbits)
>> 500 return -ERANGE;
>> 501
>> 502 for (start = r->start; start <= r->end; start += r->group_len)
>> 503 bitmap_set(bitmap, start, min(r->end - start + 1, r->off));
>> 504
>> 505 return 0;
>> 506 }
>> 507
>> 508 static int bitmap_check_region(const struct region *r)
>> 509 {
>> 510 if (r->start > r->end || r->group_len == 0 || r->off > r->group_len)
>> 511 return -EINVAL;
>> 512
>> 513 return 0;
>> 514 }
>> 515
>> 516 static const char *bitmap_getnum(const char *str, unsigned int *num)
>> 517 {
>> 518 unsigned long long n;
>> 519 unsigned int len;
>> 520
>> 521 len = _parse_integer(str, 10, &n);
>> 522 if (!len)
>> 523 return ERR_PTR(-EINVAL);
>> 524 if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n)
>> 525 return ERR_PTR(-EOVERFLOW);
>> 526
>> 527 *num = n;
>> 528 return str + len;
>> 529 }
>> 530
>> 531 static inline bool end_of_str(char c)
>> 532 {
>> 533 return c == '\0' || c == '\n';
>> 534 }
>> 535
>> 536 static inline bool __end_of_region(char c)
>> 537 {
>> 538 return isspace(c) || c == ',';
>> 539 }
>> 540
>> 541 static inline bool end_of_region(char c)
>> 542 {
>> 543 return __end_of_region(c) || end_of_str(c);
>> 544 }
>> 545
>> 546 /*
>> 547 * The format allows commas and whitespases at the beginning
>> 548 * of the region.
>> 549 */
>> 550 static const char *bitmap_find_region(const char *str)
>> 551 {
>> 552 while (__end_of_region(*str))
>> 553 str++;
>> 554
>> 555 return end_of_str(*str) ? NULL : str;
>> 556 }
>> 557
>> 558 static const char *bitmap_parse_region(const char *str, struct region *r)
>> 559 {
>> 560 str = bitmap_getnum(str, &r->start);
>> 561 if (IS_ERR(str))
>> 562 return str;
>> 563
>> 564 if (end_of_region(*str))
>> 565 goto no_end;
>> 566
>> 567 if (*str != '-')
>> 568 return ERR_PTR(-EINVAL);
>> 569
>> 570 str = bitmap_getnum(str + 1, &r->end);
>> 571 if (IS_ERR(str))
>> 572 return str;
>> 573
>> 574 if (end_of_region(*str))
>> 575 goto no_pattern;
>> 576
>> 577 if (*str != ':')
>> 578 return ERR_PTR(-EINVAL);
>> 579
>> 580 str = bitmap_getnum(str + 1, &r->off);
>> 581 if (IS_ERR(str))
>> 582 return str;
>> 583
>> 584 if (*str != '/')
>> 585 return ERR_PTR(-EINVAL);
>> 586
>> 587 return bitmap_getnum(str + 1, &r->group_len);
>> 588
>> 589 no_end:
>> 590 r->end = r->start;
>> 591 no_pattern:
>> 592 r->off = r->end + 1;
>> 593 r->group_len = r->end + 1;
>> 594
>> 595 return end_of_str(*str) ? NULL : str;
>> 596 }
>> 597
>> 598 /**
>> 599 * bitmap_parselist - convert list format ASCII string to bitmap
>> 600 * @buf: read user string from this buffer; must be terminated
>> 601 * with a \0 or \n.
>> 602 * @maskp: write resulting mask here
>> 603 * @nmaskbits: number of bits in mask to be written
>> 604 *
>> 605 * Input format is a comma-separated list of decimal numbers and
>> 606 * ranges. Consecutively set bits are shown as two hyphen-separated
>> 607 * decimal numbers, the smallest and largest bit numbers set in
>> 608 * the range.
>> 609 * Optionally each range can be postfixed to denote that only parts of it
>> 610 * should be set. The range will divided to groups of specific size.
>> 611 * From each group will be used only defined amount of bits.
>> 612 * Syntax: range:used_size/group_size
>> 613 * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769
>> 614 *
>> 615 * Returns: 0 on success, -errno on invalid input strings. Error values:
>> 616 *
>> 617 * - ``-EINVAL``: wrong region format
>> 618 * - ``-EINVAL``: invalid character in string
>> 619 * - ``-ERANGE``: bit number specified too large for mask
>> 620 * - ``-EOVERFLOW``: integer overflow in the input parameters
>> 621 */
>> 622 int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits)
>> 623 {
>> 624 struct region r;
>> 625 long ret;
>> 626
>> 627 bitmap_zero(maskp, nmaskbits);
>> 628
>> 629 while (buf) {
>> 630 buf = bitmap_find_region(buf);
>> 631 if (buf == NULL)
>> 632 return 0;
>> 633
>> 634 buf = bitmap_parse_region(buf, &r);
>> 635 if (IS_ERR(buf))
>> 636 return PTR_ERR(buf);
>> 637
>> 638 ret = bitmap_check_region(&r);
>> 639 if (ret)
>> 640 return ret;
>> 641
>> 642 ret = bitmap_set_region(&r, maskp, nmaskbits);
>> 643 if (ret)
>> 644 return ret;
>> 645 }
>> 646
>> 647 return 0;
>> 648 }
>> 649 EXPORT_SYMBOL(bitmap_parselist);
>> 650
>> 651
>> 652 /**
>> 653 * bitmap_parselist_user()
>> 654 *
>> 655 * @ubuf: pointer to user buffer containing string.
>> 656 * @ulen: buffer size in bytes. If string is smaller than this
>> 657 * then it must be terminated with a \0.
>> 658 * @maskp: pointer to bitmap array that will contain result.
>> 659 * @nmaskbits: size of bitmap, in bits.
>> 660 *
>> 661 * Wrapper for bitmap_parselist(), providing it with user buffer.
>> 662 */
>> 663 int bitmap_parselist_user(const char __user *ubuf,
>> 664 unsigned int ulen, unsigned long *maskp,
>> 665 int nmaskbits)
>> 666 {
>> 667 char *buf;
>> 668 int ret;
>> 669
>> 670 buf = memdup_user_nul(ubuf, ulen);
>> 671 if (IS_ERR(buf))
>> 672 return PTR_ERR(buf);
>> 673
>> 674 ret = bitmap_parselist(buf, maskp, nmaskbits);
>> 675
>> 676 kfree(buf);
>> 677 return ret;
>> 678 }
>> 679 EXPORT_SYMBOL(bitmap_parselist_user);
>> 680
>> 681
>> 682 #ifdef CONFIG_NUMA
439 /** 683 /**
440 * bitmap_pos_to_ord - find ordinal of set bit 684 * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap
441 * @buf: pointer to a bitmap 685 * @buf: pointer to a bitmap
442 * @pos: a bit position in @buf (0 <= @po 686 * @pos: a bit position in @buf (0 <= @pos < @nbits)
443 * @nbits: number of valid bit positions 687 * @nbits: number of valid bit positions in @buf
444 * 688 *
445 * Map the bit at position @pos in @buf (of le 689 * Map the bit at position @pos in @buf (of length @nbits) to the
446 * ordinal of which set bit it is. If it is n 690 * ordinal of which set bit it is. If it is not set or if @pos
447 * is not a valid bit position, map to -1. 691 * is not a valid bit position, map to -1.
448 * 692 *
449 * If for example, just bits 4 through 7 are s 693 * If for example, just bits 4 through 7 are set in @buf, then @pos
450 * values 4 through 7 will get mapped to 0 thr 694 * values 4 through 7 will get mapped to 0 through 3, respectively,
451 * and other @pos values will get mapped to -1 695 * and other @pos values will get mapped to -1. When @pos value 7
452 * gets mapped to (returns) @ord value 3 in th 696 * gets mapped to (returns) @ord value 3 in this example, that means
453 * that bit 7 is the 3rd (starting with 0th) s 697 * that bit 7 is the 3rd (starting with 0th) set bit in @buf.
454 * 698 *
455 * The bit positions 0 through @bits are valid 699 * The bit positions 0 through @bits are valid positions in @buf.
456 */ 700 */
457 static int bitmap_pos_to_ord(const unsigned lo 701 static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits)
458 { 702 {
459 if (pos >= nbits || !test_bit(pos, buf 703 if (pos >= nbits || !test_bit(pos, buf))
460 return -1; 704 return -1;
461 705
462 return bitmap_weight(buf, pos); !! 706 return __bitmap_weight(buf, pos);
>> 707 }
>> 708
>> 709 /**
>> 710 * bitmap_ord_to_pos - find position of n-th set bit in bitmap
>> 711 * @buf: pointer to bitmap
>> 712 * @ord: ordinal bit position (n-th set bit, n >= 0)
>> 713 * @nbits: number of valid bit positions in @buf
>> 714 *
>> 715 * Map the ordinal offset of bit @ord in @buf to its position in @buf.
>> 716 * Value of @ord should be in range 0 <= @ord < weight(buf). If @ord
>> 717 * >= weight(buf), returns @nbits.
>> 718 *
>> 719 * If for example, just bits 4 through 7 are set in @buf, then @ord
>> 720 * values 0 through 3 will get mapped to 4 through 7, respectively,
>> 721 * and all other @ord values returns @nbits. When @ord value 3
>> 722 * gets mapped to (returns) @pos value 7 in this example, that means
>> 723 * that the 3rd set bit (starting with 0th) is at position 7 in @buf.
>> 724 *
>> 725 * The bit positions 0 through @nbits-1 are valid positions in @buf.
>> 726 */
>> 727 unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits)
>> 728 {
>> 729 unsigned int pos;
>> 730
>> 731 for (pos = find_first_bit(buf, nbits);
>> 732 pos < nbits && ord;
>> 733 pos = find_next_bit(buf, nbits, pos + 1))
>> 734 ord--;
>> 735
>> 736 return pos;
463 } 737 }
464 738
465 /** 739 /**
466 * bitmap_remap - Apply map defined by a pair 740 * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap
467 * @dst: remapped result 741 * @dst: remapped result
468 * @src: subset to be remapped 742 * @src: subset to be remapped
469 * @old: defines domain of map 743 * @old: defines domain of map
470 * @new: defines range of map 744 * @new: defines range of map
471 * @nbits: number of bits in each of thes 745 * @nbits: number of bits in each of these bitmaps
472 * 746 *
473 * Let @old and @new define a mapping of bit p 747 * Let @old and @new define a mapping of bit positions, such that
474 * whatever position is held by the n-th set b 748 * whatever position is held by the n-th set bit in @old is mapped
475 * to the n-th set bit in @new. In the more g 749 * to the n-th set bit in @new. In the more general case, allowing
476 * for the possibility that the weight 'w' of 750 * for the possibility that the weight 'w' of @new is less than the
477 * weight of @old, map the position of the n-t 751 * weight of @old, map the position of the n-th set bit in @old to
478 * the position of the m-th set bit in @new, w 752 * the position of the m-th set bit in @new, where m == n % w.
479 * 753 *
480 * If either of the @old and @new bitmaps are 754 * If either of the @old and @new bitmaps are empty, or if @src and
481 * @dst point to the same location, then this 755 * @dst point to the same location, then this routine copies @src
482 * to @dst. 756 * to @dst.
483 * 757 *
484 * The positions of unset bits in @old are map 758 * The positions of unset bits in @old are mapped to themselves
485 * (the identity map). !! 759 * (the identify map).
486 * 760 *
487 * Apply the above specified mapping to @src, 761 * Apply the above specified mapping to @src, placing the result in
488 * @dst, clearing any bits previously set in @ 762 * @dst, clearing any bits previously set in @dst.
489 * 763 *
490 * For example, lets say that @old has bits 4 764 * For example, lets say that @old has bits 4 through 7 set, and
491 * @new has bits 12 through 15 set. This defi 765 * @new has bits 12 through 15 set. This defines the mapping of bit
492 * position 4 to 12, 5 to 13, 6 to 14 and 7 to 766 * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other
493 * bit positions unchanged. So if say @src co 767 * bit positions unchanged. So if say @src comes into this routine
494 * with bits 1, 5 and 7 set, then @dst should 768 * with bits 1, 5 and 7 set, then @dst should leave with bits 1,
495 * 13 and 15 set. 769 * 13 and 15 set.
496 */ 770 */
497 void bitmap_remap(unsigned long *dst, const un 771 void bitmap_remap(unsigned long *dst, const unsigned long *src,
498 const unsigned long *old, cons 772 const unsigned long *old, const unsigned long *new,
499 unsigned int nbits) 773 unsigned int nbits)
500 { 774 {
501 unsigned int oldbit, w; 775 unsigned int oldbit, w;
502 776
503 if (dst == src) /* following d 777 if (dst == src) /* following doesn't handle inplace remaps */
504 return; 778 return;
505 bitmap_zero(dst, nbits); 779 bitmap_zero(dst, nbits);
506 780
507 w = bitmap_weight(new, nbits); 781 w = bitmap_weight(new, nbits);
508 for_each_set_bit(oldbit, src, nbits) { 782 for_each_set_bit(oldbit, src, nbits) {
509 int n = bitmap_pos_to_ord(old, 783 int n = bitmap_pos_to_ord(old, oldbit, nbits);
510 784
511 if (n < 0 || w == 0) 785 if (n < 0 || w == 0)
512 set_bit(oldbit, dst); 786 set_bit(oldbit, dst); /* identity map */
513 else 787 else
514 set_bit(find_nth_bit(n !! 788 set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst);
515 } 789 }
516 } 790 }
517 EXPORT_SYMBOL(bitmap_remap); <<
518 791
519 /** 792 /**
520 * bitmap_bitremap - Apply map defined by a pa 793 * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit
521 * @oldbit: bit position to be mapped 794 * @oldbit: bit position to be mapped
522 * @old: defines domain of map 795 * @old: defines domain of map
523 * @new: defines range of map 796 * @new: defines range of map
524 * @bits: number of bits in each of these 797 * @bits: number of bits in each of these bitmaps
525 * 798 *
526 * Let @old and @new define a mapping of bit p 799 * Let @old and @new define a mapping of bit positions, such that
527 * whatever position is held by the n-th set b 800 * whatever position is held by the n-th set bit in @old is mapped
528 * to the n-th set bit in @new. In the more g 801 * to the n-th set bit in @new. In the more general case, allowing
529 * for the possibility that the weight 'w' of 802 * for the possibility that the weight 'w' of @new is less than the
530 * weight of @old, map the position of the n-t 803 * weight of @old, map the position of the n-th set bit in @old to
531 * the position of the m-th set bit in @new, w 804 * the position of the m-th set bit in @new, where m == n % w.
532 * 805 *
533 * The positions of unset bits in @old are map 806 * The positions of unset bits in @old are mapped to themselves
534 * (the identity map). !! 807 * (the identify map).
535 * 808 *
536 * Apply the above specified mapping to bit po 809 * Apply the above specified mapping to bit position @oldbit, returning
537 * the new bit position. 810 * the new bit position.
538 * 811 *
539 * For example, lets say that @old has bits 4 812 * For example, lets say that @old has bits 4 through 7 set, and
540 * @new has bits 12 through 15 set. This defi 813 * @new has bits 12 through 15 set. This defines the mapping of bit
541 * position 4 to 12, 5 to 13, 6 to 14 and 7 to 814 * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other
542 * bit positions unchanged. So if say @oldbit 815 * bit positions unchanged. So if say @oldbit is 5, then this routine
543 * returns 13. 816 * returns 13.
544 */ 817 */
545 int bitmap_bitremap(int oldbit, const unsigned 818 int bitmap_bitremap(int oldbit, const unsigned long *old,
546 const unsigned 819 const unsigned long *new, int bits)
547 { 820 {
548 int w = bitmap_weight(new, bits); 821 int w = bitmap_weight(new, bits);
549 int n = bitmap_pos_to_ord(old, oldbit, 822 int n = bitmap_pos_to_ord(old, oldbit, bits);
550 if (n < 0 || w == 0) 823 if (n < 0 || w == 0)
551 return oldbit; 824 return oldbit;
552 else 825 else
553 return find_nth_bit(new, bits, !! 826 return bitmap_ord_to_pos(new, n % w, bits);
554 } 827 }
555 EXPORT_SYMBOL(bitmap_bitremap); <<
556 828
557 #ifdef CONFIG_NUMA <<
558 /** 829 /**
559 * bitmap_onto - translate one bitmap relative 830 * bitmap_onto - translate one bitmap relative to another
560 * @dst: resulting translated bitmap 831 * @dst: resulting translated bitmap
561 * @orig: original untranslated bitmap 832 * @orig: original untranslated bitmap
562 * @relmap: bitmap relative to which tran 833 * @relmap: bitmap relative to which translated
563 * @bits: number of bits in each of these 834 * @bits: number of bits in each of these bitmaps
564 * 835 *
565 * Set the n-th bit of @dst iff there exists s 836 * Set the n-th bit of @dst iff there exists some m such that the
566 * n-th bit of @relmap is set, the m-th bit of 837 * n-th bit of @relmap is set, the m-th bit of @orig is set, and
567 * the n-th bit of @relmap is also the m-th _s 838 * the n-th bit of @relmap is also the m-th _set_ bit of @relmap.
568 * (If you understood the previous sentence th 839 * (If you understood the previous sentence the first time your
569 * read it, you're overqualified for your curr 840 * read it, you're overqualified for your current job.)
570 * 841 *
571 * In other words, @orig is mapped onto (surje 842 * In other words, @orig is mapped onto (surjectively) @dst,
572 * using the map { <n, m> | the n-th bit of @r 843 * using the map { <n, m> | the n-th bit of @relmap is the
573 * m-th set bit of @relmap }. 844 * m-th set bit of @relmap }.
574 * 845 *
575 * Any set bits in @orig above bit number W, w 846 * Any set bits in @orig above bit number W, where W is the
576 * weight of (number of set bits in) @relmap a 847 * weight of (number of set bits in) @relmap are mapped nowhere.
577 * In particular, if for all bits m set in @or 848 * In particular, if for all bits m set in @orig, m >= W, then
578 * @dst will end up empty. In situations wher 849 * @dst will end up empty. In situations where the possibility
579 * of such an empty result is not desired, one 850 * of such an empty result is not desired, one way to avoid it is
580 * to use the bitmap_fold() operator, below, t 851 * to use the bitmap_fold() operator, below, to first fold the
581 * @orig bitmap over itself so that all its se 852 * @orig bitmap over itself so that all its set bits x are in the
582 * range 0 <= x < W. The bitmap_fold() operat 853 * range 0 <= x < W. The bitmap_fold() operator does this by
583 * setting the bit (m % W) in @dst, for each b 854 * setting the bit (m % W) in @dst, for each bit (m) set in @orig.
584 * 855 *
585 * Example [1] for bitmap_onto(): 856 * Example [1] for bitmap_onto():
586 * Let's say @relmap has bits 30-39 set, and 857 * Let's say @relmap has bits 30-39 set, and @orig has bits
587 * 1, 3, 5, 7, 9 and 11 set. Then on return 858 * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine,
588 * @dst will have bits 31, 33, 35, 37 and 39 859 * @dst will have bits 31, 33, 35, 37 and 39 set.
589 * 860 *
590 * When bit 0 is set in @orig, it means turn 861 * When bit 0 is set in @orig, it means turn on the bit in
591 * @dst corresponding to whatever is the firs 862 * @dst corresponding to whatever is the first bit (if any)
592 * that is turned on in @relmap. Since bit 0 863 * that is turned on in @relmap. Since bit 0 was off in the
593 * above example, we leave off that bit (bit 864 * above example, we leave off that bit (bit 30) in @dst.
594 * 865 *
595 * When bit 1 is set in @orig (as in the abov 866 * When bit 1 is set in @orig (as in the above example), it
596 * means turn on the bit in @dst correspondin 867 * means turn on the bit in @dst corresponding to whatever
597 * is the second bit that is turned on in @re 868 * is the second bit that is turned on in @relmap. The second
598 * bit in @relmap that was turned on in the a 869 * bit in @relmap that was turned on in the above example was
599 * bit 31, so we turned on bit 31 in @dst. 870 * bit 31, so we turned on bit 31 in @dst.
600 * 871 *
601 * Similarly, we turned on bits 33, 35, 37 an 872 * Similarly, we turned on bits 33, 35, 37 and 39 in @dst,
602 * because they were the 4th, 6th, 8th and 10 873 * because they were the 4th, 6th, 8th and 10th set bits
603 * set in @relmap, and the 4th, 6th, 8th and 874 * set in @relmap, and the 4th, 6th, 8th and 10th bits of
604 * @orig (i.e. bits 3, 5, 7 and 9) were also 875 * @orig (i.e. bits 3, 5, 7 and 9) were also set.
605 * 876 *
606 * When bit 11 is set in @orig, it means turn 877 * When bit 11 is set in @orig, it means turn on the bit in
607 * @dst corresponding to whatever is the twel 878 * @dst corresponding to whatever is the twelfth bit that is
608 * turned on in @relmap. In the above exampl 879 * turned on in @relmap. In the above example, there were
609 * only ten bits turned on in @relmap (30..39 880 * only ten bits turned on in @relmap (30..39), so that bit
610 * 11 was set in @orig had no affect on @dst. 881 * 11 was set in @orig had no affect on @dst.
611 * 882 *
612 * Example [2] for bitmap_fold() + bitmap_onto 883 * Example [2] for bitmap_fold() + bitmap_onto():
613 * Let's say @relmap has these ten bits set:: 884 * Let's say @relmap has these ten bits set::
614 * 885 *
615 * 40 41 42 43 45 48 53 61 74 95 886 * 40 41 42 43 45 48 53 61 74 95
616 * 887 *
617 * (for the curious, that's 40 plus the first 888 * (for the curious, that's 40 plus the first ten terms of the
618 * Fibonacci sequence.) 889 * Fibonacci sequence.)
619 * 890 *
620 * Further lets say we use the following code 891 * Further lets say we use the following code, invoking
621 * bitmap_fold() then bitmap_onto, as suggest 892 * bitmap_fold() then bitmap_onto, as suggested above to
622 * avoid the possibility of an empty @dst res 893 * avoid the possibility of an empty @dst result::
623 * 894 *
624 * unsigned long *tmp; // a temporary 895 * unsigned long *tmp; // a temporary bitmap's bits
625 * 896 *
626 * bitmap_fold(tmp, orig, bitmap_weight(r 897 * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits);
627 * bitmap_onto(dst, tmp, relmap, bits); 898 * bitmap_onto(dst, tmp, relmap, bits);
628 * 899 *
629 * Then this table shows what various values 900 * Then this table shows what various values of @dst would be, for
630 * various @orig's. I list the zero-based po 901 * various @orig's. I list the zero-based positions of each set bit.
631 * The tmp column shows the intermediate resu 902 * The tmp column shows the intermediate result, as computed by
632 * using bitmap_fold() to fold the @orig bitm 903 * using bitmap_fold() to fold the @orig bitmap modulo ten
633 * (the weight of @relmap): 904 * (the weight of @relmap):
634 * 905 *
635 * =============== ============== ======= 906 * =============== ============== =================
636 * @orig tmp @dst 907 * @orig tmp @dst
637 * 0 0 40 908 * 0 0 40
638 * 1 1 41 909 * 1 1 41
639 * 9 9 95 910 * 9 9 95
640 * 10 0 40 [#f1 911 * 10 0 40 [#f1]_
641 * 1 3 5 7 1 3 5 7 41 43 4 912 * 1 3 5 7 1 3 5 7 41 43 48 61
642 * 0 1 2 3 4 0 1 2 3 4 40 41 4 913 * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45
643 * 0 9 18 27 0 9 8 7 40 61 7 914 * 0 9 18 27 0 9 8 7 40 61 74 95
644 * 0 10 20 30 0 40 915 * 0 10 20 30 0 40
645 * 0 11 22 33 0 1 2 3 40 41 4 916 * 0 11 22 33 0 1 2 3 40 41 42 43
646 * 0 12 24 36 0 2 4 6 40 42 4 917 * 0 12 24 36 0 2 4 6 40 42 45 53
647 * 78 102 211 1 2 8 41 42 7 918 * 78 102 211 1 2 8 41 42 74 [#f1]_
648 * =============== ============== ======= 919 * =============== ============== =================
649 * 920 *
650 * .. [#f1] 921 * .. [#f1]
651 * 922 *
652 * For these marked lines, if we hadn't fi 923 * For these marked lines, if we hadn't first done bitmap_fold()
653 * into tmp, then the @dst result would ha 924 * into tmp, then the @dst result would have been empty.
654 * 925 *
655 * If either of @orig or @relmap is empty (no 926 * If either of @orig or @relmap is empty (no set bits), then @dst
656 * will be returned empty. 927 * will be returned empty.
657 * 928 *
658 * If (as explained above) the only set bits i 929 * If (as explained above) the only set bits in @orig are in positions
659 * m where m >= W, (where W is the weight of @ 930 * m where m >= W, (where W is the weight of @relmap) then @dst will
660 * once again be returned empty. 931 * once again be returned empty.
661 * 932 *
662 * All bits in @dst not set by the above rule 933 * All bits in @dst not set by the above rule are cleared.
663 */ 934 */
664 void bitmap_onto(unsigned long *dst, const uns 935 void bitmap_onto(unsigned long *dst, const unsigned long *orig,
665 const unsigned long *r 936 const unsigned long *relmap, unsigned int bits)
666 { 937 {
667 unsigned int n, m; /* same meanin 938 unsigned int n, m; /* same meaning as in above comment */
668 939
669 if (dst == orig) /* following d 940 if (dst == orig) /* following doesn't handle inplace mappings */
670 return; 941 return;
671 bitmap_zero(dst, bits); 942 bitmap_zero(dst, bits);
672 943
673 /* 944 /*
674 * The following code is a more effici 945 * The following code is a more efficient, but less
675 * obvious, equivalent to the loop: 946 * obvious, equivalent to the loop:
676 * for (m = 0; m < bitmap_weight( 947 * for (m = 0; m < bitmap_weight(relmap, bits); m++) {
677 * n = find_nth_bit(orig, !! 948 * n = bitmap_ord_to_pos(orig, m, bits);
678 * if (test_bit(m, orig)) 949 * if (test_bit(m, orig))
679 * set_bit(n, dst 950 * set_bit(n, dst);
680 * } 951 * }
681 */ 952 */
682 953
683 m = 0; 954 m = 0;
684 for_each_set_bit(n, relmap, bits) { 955 for_each_set_bit(n, relmap, bits) {
685 /* m == bitmap_pos_to_ord(relm 956 /* m == bitmap_pos_to_ord(relmap, n, bits) */
686 if (test_bit(m, orig)) 957 if (test_bit(m, orig))
687 set_bit(n, dst); 958 set_bit(n, dst);
688 m++; 959 m++;
689 } 960 }
690 } 961 }
691 962
692 /** 963 /**
693 * bitmap_fold - fold larger bitmap into small 964 * bitmap_fold - fold larger bitmap into smaller, modulo specified size
694 * @dst: resulting smaller bitmap 965 * @dst: resulting smaller bitmap
695 * @orig: original larger bitmap 966 * @orig: original larger bitmap
696 * @sz: specified size 967 * @sz: specified size
697 * @nbits: number of bits in each of thes 968 * @nbits: number of bits in each of these bitmaps
698 * 969 *
699 * For each bit oldbit in @orig, set bit oldbi 970 * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst.
700 * Clear all other bits in @dst. See further 971 * Clear all other bits in @dst. See further the comment and
701 * Example [2] for bitmap_onto() for why and h 972 * Example [2] for bitmap_onto() for why and how to use this.
702 */ 973 */
703 void bitmap_fold(unsigned long *dst, const uns 974 void bitmap_fold(unsigned long *dst, const unsigned long *orig,
704 unsigned int sz, unsig 975 unsigned int sz, unsigned int nbits)
705 { 976 {
706 unsigned int oldbit; 977 unsigned int oldbit;
707 978
708 if (dst == orig) /* following d 979 if (dst == orig) /* following doesn't handle inplace mappings */
709 return; 980 return;
710 bitmap_zero(dst, nbits); 981 bitmap_zero(dst, nbits);
711 982
712 for_each_set_bit(oldbit, orig, nbits) 983 for_each_set_bit(oldbit, orig, nbits)
713 set_bit(oldbit % sz, dst); 984 set_bit(oldbit % sz, dst);
714 } 985 }
715 #endif /* CONFIG_NUMA */ 986 #endif /* CONFIG_NUMA */
716 987
717 unsigned long *bitmap_alloc(unsigned int nbits !! 988 /*
718 { !! 989 * Common code for bitmap_*_region() routines.
719 return kmalloc_array(BITS_TO_LONGS(nbi !! 990 * bitmap: array of unsigned longs corresponding to the bitmap
720 flags); !! 991 * pos: the beginning of the region
721 } !! 992 * order: region size (log base 2 of number of bits)
722 EXPORT_SYMBOL(bitmap_alloc); !! 993 * reg_op: operation(s) to perform on that region of bitmap
>> 994 *
>> 995 * Can set, verify and/or release a region of bits in a bitmap,
>> 996 * depending on which combination of REG_OP_* flag bits is set.
>> 997 *
>> 998 * A region of a bitmap is a sequence of bits in the bitmap, of
>> 999 * some size '1 << order' (a power of two), aligned to that same
>> 1000 * '1 << order' power of two.
>> 1001 *
>> 1002 * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits).
>> 1003 * Returns 0 in all other cases and reg_ops.
>> 1004 */
723 1005
724 unsigned long *bitmap_zalloc(unsigned int nbit !! 1006 enum {
725 { !! 1007 REG_OP_ISFREE, /* true if region is all zero bits */
726 return bitmap_alloc(nbits, flags | __G !! 1008 REG_OP_ALLOC, /* set all bits in region */
>> 1009 REG_OP_RELEASE, /* clear all bits in region */
>> 1010 };
>> 1011
>> 1012 static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op)
>> 1013 {
>> 1014 int nbits_reg; /* number of bits in region */
>> 1015 int index; /* index first long of region in bitmap */
>> 1016 int offset; /* bit offset region in bitmap[index] */
>> 1017 int nlongs_reg; /* num longs spanned by region in bitmap */
>> 1018 int nbitsinlong; /* num bits of region in each spanned long */
>> 1019 unsigned long mask; /* bitmask for one long of region */
>> 1020 int i; /* scans bitmap by longs */
>> 1021 int ret = 0; /* return value */
>> 1022
>> 1023 /*
>> 1024 * Either nlongs_reg == 1 (for small orders that fit in one long)
>> 1025 * or (offset == 0 && mask == ~0UL) (for larger multiword orders.)
>> 1026 */
>> 1027 nbits_reg = 1 << order;
>> 1028 index = pos / BITS_PER_LONG;
>> 1029 offset = pos - (index * BITS_PER_LONG);
>> 1030 nlongs_reg = BITS_TO_LONGS(nbits_reg);
>> 1031 nbitsinlong = min(nbits_reg, BITS_PER_LONG);
>> 1032
>> 1033 /*
>> 1034 * Can't do "mask = (1UL << nbitsinlong) - 1", as that
>> 1035 * overflows if nbitsinlong == BITS_PER_LONG.
>> 1036 */
>> 1037 mask = (1UL << (nbitsinlong - 1));
>> 1038 mask += mask - 1;
>> 1039 mask <<= offset;
>> 1040
>> 1041 switch (reg_op) {
>> 1042 case REG_OP_ISFREE:
>> 1043 for (i = 0; i < nlongs_reg; i++) {
>> 1044 if (bitmap[index + i] & mask)
>> 1045 goto done;
>> 1046 }
>> 1047 ret = 1; /* all bits in region free (zero) */
>> 1048 break;
>> 1049
>> 1050 case REG_OP_ALLOC:
>> 1051 for (i = 0; i < nlongs_reg; i++)
>> 1052 bitmap[index + i] |= mask;
>> 1053 break;
>> 1054
>> 1055 case REG_OP_RELEASE:
>> 1056 for (i = 0; i < nlongs_reg; i++)
>> 1057 bitmap[index + i] &= ~mask;
>> 1058 break;
>> 1059 }
>> 1060 done:
>> 1061 return ret;
727 } 1062 }
728 EXPORT_SYMBOL(bitmap_zalloc); <<
729 1063
730 unsigned long *bitmap_alloc_node(unsigned int !! 1064 /**
>> 1065 * bitmap_find_free_region - find a contiguous aligned mem region
>> 1066 * @bitmap: array of unsigned longs corresponding to the bitmap
>> 1067 * @bits: number of bits in the bitmap
>> 1068 * @order: region size (log base 2 of number of bits) to find
>> 1069 *
>> 1070 * Find a region of free (zero) bits in a @bitmap of @bits bits and
>> 1071 * allocate them (set them to one). Only consider regions of length
>> 1072 * a power (@order) of two, aligned to that power of two, which
>> 1073 * makes the search algorithm much faster.
>> 1074 *
>> 1075 * Return the bit offset in bitmap of the allocated region,
>> 1076 * or -errno on failure.
>> 1077 */
>> 1078 int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order)
731 { 1079 {
732 return kmalloc_array_node(BITS_TO_LONG !! 1080 unsigned int pos, end; /* scans bitmap by regions of size order */
733 flags, node) !! 1081
>> 1082 for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) {
>> 1083 if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
>> 1084 continue;
>> 1085 __reg_op(bitmap, pos, order, REG_OP_ALLOC);
>> 1086 return pos;
>> 1087 }
>> 1088 return -ENOMEM;
734 } 1089 }
735 EXPORT_SYMBOL(bitmap_alloc_node); !! 1090 EXPORT_SYMBOL(bitmap_find_free_region);
736 1091
737 unsigned long *bitmap_zalloc_node(unsigned int !! 1092 /**
>> 1093 * bitmap_release_region - release allocated bitmap region
>> 1094 * @bitmap: array of unsigned longs corresponding to the bitmap
>> 1095 * @pos: beginning of bit region to release
>> 1096 * @order: region size (log base 2 of number of bits) to release
>> 1097 *
>> 1098 * This is the complement to __bitmap_find_free_region() and releases
>> 1099 * the found region (by clearing it in the bitmap).
>> 1100 *
>> 1101 * No return value.
>> 1102 */
>> 1103 void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order)
738 { 1104 {
739 return bitmap_alloc_node(nbits, flags !! 1105 __reg_op(bitmap, pos, order, REG_OP_RELEASE);
740 } 1106 }
741 EXPORT_SYMBOL(bitmap_zalloc_node); !! 1107 EXPORT_SYMBOL(bitmap_release_region);
742 1108
743 void bitmap_free(const unsigned long *bitmap) !! 1109 /**
>> 1110 * bitmap_allocate_region - allocate bitmap region
>> 1111 * @bitmap: array of unsigned longs corresponding to the bitmap
>> 1112 * @pos: beginning of bit region to allocate
>> 1113 * @order: region size (log base 2 of number of bits) to allocate
>> 1114 *
>> 1115 * Allocate (set bits in) a specified region of a bitmap.
>> 1116 *
>> 1117 * Return 0 on success, or %-EBUSY if specified region wasn't
>> 1118 * free (not all bits were zero).
>> 1119 */
>> 1120 int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order)
744 { 1121 {
745 kfree(bitmap); !! 1122 if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
>> 1123 return -EBUSY;
>> 1124 return __reg_op(bitmap, pos, order, REG_OP_ALLOC);
746 } 1125 }
747 EXPORT_SYMBOL(bitmap_free); !! 1126 EXPORT_SYMBOL(bitmap_allocate_region);
748 1127
749 static void devm_bitmap_free(void *data) !! 1128 /**
>> 1129 * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order.
>> 1130 * @dst: destination buffer
>> 1131 * @src: bitmap to copy
>> 1132 * @nbits: number of bits in the bitmap
>> 1133 *
>> 1134 * Require nbits % BITS_PER_LONG == 0.
>> 1135 */
>> 1136 #ifdef __BIG_ENDIAN
>> 1137 void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits)
750 { 1138 {
751 unsigned long *bitmap = data; !! 1139 unsigned int i;
752 1140
753 bitmap_free(bitmap); !! 1141 for (i = 0; i < nbits/BITS_PER_LONG; i++) {
>> 1142 if (BITS_PER_LONG == 64)
>> 1143 dst[i] = cpu_to_le64(src[i]);
>> 1144 else
>> 1145 dst[i] = cpu_to_le32(src[i]);
>> 1146 }
754 } 1147 }
>> 1148 EXPORT_SYMBOL(bitmap_copy_le);
>> 1149 #endif
755 1150
756 unsigned long *devm_bitmap_alloc(struct device !! 1151 unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags)
757 unsigned int <<
758 { 1152 {
759 unsigned long *bitmap; !! 1153 return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long),
760 int ret; !! 1154 flags);
761 !! 1155 }
762 bitmap = bitmap_alloc(nbits, flags); !! 1156 EXPORT_SYMBOL(bitmap_alloc);
763 if (!bitmap) <<
764 return NULL; <<
765 <<
766 ret = devm_add_action_or_reset(dev, de <<
767 if (ret) <<
768 return NULL; <<
769 1157
770 return bitmap; !! 1158 unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags)
>> 1159 {
>> 1160 return bitmap_alloc(nbits, flags | __GFP_ZERO);
771 } 1161 }
772 EXPORT_SYMBOL_GPL(devm_bitmap_alloc); !! 1162 EXPORT_SYMBOL(bitmap_zalloc);
773 1163
774 unsigned long *devm_bitmap_zalloc(struct devic !! 1164 void bitmap_free(const unsigned long *bitmap)
775 unsigned int <<
776 { 1165 {
777 return devm_bitmap_alloc(dev, nbits, f !! 1166 kfree(bitmap);
778 } 1167 }
779 EXPORT_SYMBOL_GPL(devm_bitmap_zalloc); !! 1168 EXPORT_SYMBOL(bitmap_free);
780 1169
781 #if BITS_PER_LONG == 64 1170 #if BITS_PER_LONG == 64
782 /** 1171 /**
783 * bitmap_from_arr32 - copy the contents of u3 1172 * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap
784 * @bitmap: array of unsigned longs, the 1173 * @bitmap: array of unsigned longs, the destination bitmap
785 * @buf: array of u32 (in host byte order 1174 * @buf: array of u32 (in host byte order), the source bitmap
786 * @nbits: number of bits in @bitmap 1175 * @nbits: number of bits in @bitmap
787 */ 1176 */
788 void bitmap_from_arr32(unsigned long *bitmap, 1177 void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits)
789 { 1178 {
790 unsigned int i, halfwords; 1179 unsigned int i, halfwords;
791 1180
792 halfwords = DIV_ROUND_UP(nbits, 32); 1181 halfwords = DIV_ROUND_UP(nbits, 32);
793 for (i = 0; i < halfwords; i++) { 1182 for (i = 0; i < halfwords; i++) {
794 bitmap[i/2] = (unsigned long) 1183 bitmap[i/2] = (unsigned long) buf[i];
795 if (++i < halfwords) 1184 if (++i < halfwords)
796 bitmap[i/2] |= ((unsig 1185 bitmap[i/2] |= ((unsigned long) buf[i]) << 32;
797 } 1186 }
798 1187
799 /* Clear tail bits in last word beyond 1188 /* Clear tail bits in last word beyond nbits. */
800 if (nbits % BITS_PER_LONG) 1189 if (nbits % BITS_PER_LONG)
801 bitmap[(halfwords - 1) / 2] &= 1190 bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits);
802 } 1191 }
803 EXPORT_SYMBOL(bitmap_from_arr32); 1192 EXPORT_SYMBOL(bitmap_from_arr32);
804 1193
805 /** 1194 /**
806 * bitmap_to_arr32 - copy the contents of bitm 1195 * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits
807 * @buf: array of u32 (in host byte order 1196 * @buf: array of u32 (in host byte order), the dest bitmap
808 * @bitmap: array of unsigned longs, the 1197 * @bitmap: array of unsigned longs, the source bitmap
809 * @nbits: number of bits in @bitmap 1198 * @nbits: number of bits in @bitmap
810 */ 1199 */
811 void bitmap_to_arr32(u32 *buf, const unsigned 1200 void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits)
812 { 1201 {
813 unsigned int i, halfwords; 1202 unsigned int i, halfwords;
814 1203
815 halfwords = DIV_ROUND_UP(nbits, 32); 1204 halfwords = DIV_ROUND_UP(nbits, 32);
816 for (i = 0; i < halfwords; i++) { 1205 for (i = 0; i < halfwords; i++) {
817 buf[i] = (u32) (bitmap[i/2] & 1206 buf[i] = (u32) (bitmap[i/2] & UINT_MAX);
818 if (++i < halfwords) 1207 if (++i < halfwords)
819 buf[i] = (u32) (bitmap 1208 buf[i] = (u32) (bitmap[i/2] >> 32);
820 } 1209 }
821 1210
822 /* Clear tail bits in last element of 1211 /* Clear tail bits in last element of array beyond nbits. */
823 if (nbits % BITS_PER_LONG) 1212 if (nbits % BITS_PER_LONG)
824 buf[halfwords - 1] &= (u32) (U 1213 buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31));
825 } 1214 }
826 EXPORT_SYMBOL(bitmap_to_arr32); 1215 EXPORT_SYMBOL(bitmap_to_arr32);
827 #endif <<
828 <<
829 #if BITS_PER_LONG == 32 <<
830 /** <<
831 * bitmap_from_arr64 - copy the contents of u6 <<
832 * @bitmap: array of unsigned longs, the <<
833 * @buf: array of u64 (in host byte order <<
834 * @nbits: number of bits in @bitmap <<
835 */ <<
836 void bitmap_from_arr64(unsigned long *bitmap, <<
837 { <<
838 int n; <<
839 <<
840 for (n = nbits; n > 0; n -= 64) { <<
841 u64 val = *buf++; <<
842 <<
843 *bitmap++ = val; <<
844 if (n > 32) <<
845 *bitmap++ = val >> 32; <<
846 } <<
847 <<
848 /* <<
849 * Clear tail bits in the last word be <<
850 * <<
851 * Negative index is OK because here w <<
852 * to the last word of the bitmap, exc <<
853 * is tested implicitly. <<
854 */ <<
855 if (nbits % BITS_PER_LONG) <<
856 bitmap[-1] &= BITMAP_LAST_WORD <<
857 } <<
858 EXPORT_SYMBOL(bitmap_from_arr64); <<
859 1216
860 /** <<
861 * bitmap_to_arr64 - copy the contents of bitm <<
862 * @buf: array of u64 (in host byte order <<
863 * @bitmap: array of unsigned longs, the <<
864 * @nbits: number of bits in @bitmap <<
865 */ <<
866 void bitmap_to_arr64(u64 *buf, const unsigned <<
867 { <<
868 const unsigned long *end = bitmap + BI <<
869 <<
870 while (bitmap < end) { <<
871 *buf = *bitmap++; <<
872 if (bitmap < end) <<
873 *buf |= (u64)(*bitmap+ <<
874 buf++; <<
875 } <<
876 <<
877 /* Clear tail bits in the last element <<
878 if (nbits % 64) <<
879 buf[-1] &= GENMASK_ULL((nbits <<
880 } <<
881 EXPORT_SYMBOL(bitmap_to_arr64); <<
882 #endif 1217 #endif
883 1218
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