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
7 #include <linux/bitmap.h> 7 #include <linux/bitmap.h>
8 #include <linux/bitops.h> 8 #include <linux/bitops.h>
9 #include <linux/ctype.h> 9 #include <linux/ctype.h>
10 #include <linux/device.h> 10 #include <linux/device.h>
11 #include <linux/export.h> 11 #include <linux/export.h>
12 #include <linux/slab.h> 12 #include <linux/slab.h>
13 13
14 /** 14 /**
15 * DOC: bitmap introduction 15 * DOC: bitmap introduction
16 * 16 *
17 * bitmaps provide an array of bits, implement 17 * bitmaps provide an array of bits, implemented using an
18 * array of unsigned longs. The number of val 18 * array of unsigned longs. The number of valid bits in a
19 * given bitmap does _not_ need to be an exact 19 * given bitmap does _not_ need to be an exact multiple of
20 * BITS_PER_LONG. 20 * BITS_PER_LONG.
21 * 21 *
22 * The possible unused bits in the last, parti 22 * The possible unused bits in the last, partially used word
23 * of a bitmap are 'don't care'. The implemen 23 * of a bitmap are 'don't care'. The implementation makes
24 * no particular effort to keep them zero. It 24 * no particular effort to keep them zero. It ensures that
25 * their value will not affect the results of 25 * their value will not affect the results of any operation.
26 * The bitmap operations that return Boolean ( 26 * The bitmap operations that return Boolean (bitmap_empty,
27 * for example) or scalar (bitmap_weight, for 27 * for example) or scalar (bitmap_weight, for example) results
28 * carefully filter out these unused bits from 28 * carefully filter out these unused bits from impacting their
29 * results. 29 * results.
30 * 30 *
31 * The byte ordering of bitmaps is more natura 31 * The byte ordering of bitmaps is more natural on little
32 * endian architectures. See the big-endian h 32 * endian architectures. See the big-endian headers
33 * include/asm-ppc64/bitops.h and include/asm- 33 * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h
34 * for the best explanations of this ordering. 34 * for the best explanations of this ordering.
35 */ 35 */
36 36
37 bool __bitmap_equal(const unsigned long *bitma 37 bool __bitmap_equal(const unsigned long *bitmap1,
38 const unsigned long *bitma 38 const unsigned long *bitmap2, unsigned int bits)
39 { 39 {
40 unsigned int k, lim = bits/BITS_PER_LO 40 unsigned int k, lim = bits/BITS_PER_LONG;
41 for (k = 0; k < lim; ++k) 41 for (k = 0; k < lim; ++k)
42 if (bitmap1[k] != bitmap2[k]) 42 if (bitmap1[k] != bitmap2[k])
43 return false; 43 return false;
44 44
45 if (bits % BITS_PER_LONG) 45 if (bits % BITS_PER_LONG)
46 if ((bitmap1[k] ^ bitmap2[k]) 46 if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
47 return false; 47 return false;
48 48
49 return true; 49 return true;
50 } 50 }
51 EXPORT_SYMBOL(__bitmap_equal); 51 EXPORT_SYMBOL(__bitmap_equal);
52 52
53 bool __bitmap_or_equal(const unsigned long *bi 53 bool __bitmap_or_equal(const unsigned long *bitmap1,
54 const unsigned long *bi 54 const unsigned long *bitmap2,
55 const unsigned long *bi 55 const unsigned long *bitmap3,
56 unsigned int bits) 56 unsigned int bits)
57 { 57 {
58 unsigned int k, lim = bits / BITS_PER_ 58 unsigned int k, lim = bits / BITS_PER_LONG;
59 unsigned long tmp; 59 unsigned long tmp;
60 60
61 for (k = 0; k < lim; ++k) { 61 for (k = 0; k < lim; ++k) {
62 if ((bitmap1[k] | bitmap2[k]) 62 if ((bitmap1[k] | bitmap2[k]) != bitmap3[k])
63 return false; 63 return false;
64 } 64 }
65 65
66 if (!(bits % BITS_PER_LONG)) 66 if (!(bits % BITS_PER_LONG))
67 return true; 67 return true;
68 68
69 tmp = (bitmap1[k] | bitmap2[k]) ^ bitm 69 tmp = (bitmap1[k] | bitmap2[k]) ^ bitmap3[k];
70 return (tmp & BITMAP_LAST_WORD_MASK(bi 70 return (tmp & BITMAP_LAST_WORD_MASK(bits)) == 0;
71 } 71 }
72 72
73 void __bitmap_complement(unsigned long *dst, c 73 void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits)
74 { 74 {
75 unsigned int k, lim = BITS_TO_LONGS(bi 75 unsigned int k, lim = BITS_TO_LONGS(bits);
76 for (k = 0; k < lim; ++k) 76 for (k = 0; k < lim; ++k)
77 dst[k] = ~src[k]; 77 dst[k] = ~src[k];
78 } 78 }
79 EXPORT_SYMBOL(__bitmap_complement); 79 EXPORT_SYMBOL(__bitmap_complement);
80 80
81 /** 81 /**
82 * __bitmap_shift_right - logical right shift 82 * __bitmap_shift_right - logical right shift of the bits in a bitmap
83 * @dst : destination bitmap 83 * @dst : destination bitmap
84 * @src : source bitmap 84 * @src : source bitmap
85 * @shift : shift by this many bits 85 * @shift : shift by this many bits
86 * @nbits : bitmap size, in bits 86 * @nbits : bitmap size, in bits
87 * 87 *
88 * Shifting right (dividing) means moving bits 88 * Shifting right (dividing) means moving bits in the MS -> LS bit
89 * direction. Zeros are fed into the vacated 89 * direction. Zeros are fed into the vacated MS positions and the
90 * LS bits shifted off the bottom are lost. 90 * LS bits shifted off the bottom are lost.
91 */ 91 */
92 void __bitmap_shift_right(unsigned long *dst, 92 void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
93 unsigned shift, unsign 93 unsigned shift, unsigned nbits)
94 { 94 {
95 unsigned k, lim = BITS_TO_LONGS(nbits) 95 unsigned k, lim = BITS_TO_LONGS(nbits);
96 unsigned off = shift/BITS_PER_LONG, re 96 unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG;
97 unsigned long mask = BITMAP_LAST_WORD_ 97 unsigned long mask = BITMAP_LAST_WORD_MASK(nbits);
98 for (k = 0; off + k < lim; ++k) { 98 for (k = 0; off + k < lim; ++k) {
99 unsigned long upper, lower; 99 unsigned long upper, lower;
100 100
101 /* 101 /*
102 * If shift is not word aligne 102 * If shift is not word aligned, take lower rem bits of
103 * word above and make them th 103 * word above and make them the top rem bits of result.
104 */ 104 */
105 if (!rem || off + k + 1 >= lim 105 if (!rem || off + k + 1 >= lim)
106 upper = 0; 106 upper = 0;
107 else { 107 else {
108 upper = src[off + k + 108 upper = src[off + k + 1];
109 if (off + k + 1 == lim 109 if (off + k + 1 == lim - 1)
110 upper &= mask; 110 upper &= mask;
111 upper <<= (BITS_PER_LO 111 upper <<= (BITS_PER_LONG - rem);
112 } 112 }
113 lower = src[off + k]; 113 lower = src[off + k];
114 if (off + k == lim - 1) 114 if (off + k == lim - 1)
115 lower &= mask; 115 lower &= mask;
116 lower >>= rem; 116 lower >>= rem;
117 dst[k] = lower | upper; 117 dst[k] = lower | upper;
118 } 118 }
119 if (off) 119 if (off)
120 memset(&dst[lim - off], 0, off 120 memset(&dst[lim - off], 0, off*sizeof(unsigned long));
121 } 121 }
122 EXPORT_SYMBOL(__bitmap_shift_right); 122 EXPORT_SYMBOL(__bitmap_shift_right);
123 123
124 124
125 /** 125 /**
126 * __bitmap_shift_left - logical left shift of 126 * __bitmap_shift_left - logical left shift of the bits in a bitmap
127 * @dst : destination bitmap 127 * @dst : destination bitmap
128 * @src : source bitmap 128 * @src : source bitmap
129 * @shift : shift by this many bits 129 * @shift : shift by this many bits
130 * @nbits : bitmap size, in bits 130 * @nbits : bitmap size, in bits
131 * 131 *
132 * Shifting left (multiplying) means moving bi 132 * Shifting left (multiplying) means moving bits in the LS -> MS
133 * direction. Zeros are fed into the vacated 133 * direction. Zeros are fed into the vacated LS bit positions
134 * and those MS bits shifted off the top are l 134 * and those MS bits shifted off the top are lost.
135 */ 135 */
136 136
137 void __bitmap_shift_left(unsigned long *dst, c 137 void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
138 unsigned int shift, un 138 unsigned int shift, unsigned int nbits)
139 { 139 {
140 int k; 140 int k;
141 unsigned int lim = BITS_TO_LONGS(nbits 141 unsigned int lim = BITS_TO_LONGS(nbits);
142 unsigned int off = shift/BITS_PER_LONG 142 unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG;
143 for (k = lim - off - 1; k >= 0; --k) { 143 for (k = lim - off - 1; k >= 0; --k) {
144 unsigned long upper, lower; 144 unsigned long upper, lower;
145 145
146 /* 146 /*
147 * If shift is not word aligne 147 * If shift is not word aligned, take upper rem bits of
148 * word below and make them th 148 * word below and make them the bottom rem bits of result.
149 */ 149 */
150 if (rem && k > 0) 150 if (rem && k > 0)
151 lower = src[k - 1] >> 151 lower = src[k - 1] >> (BITS_PER_LONG - rem);
152 else 152 else
153 lower = 0; 153 lower = 0;
154 upper = src[k] << rem; 154 upper = src[k] << rem;
155 dst[k + off] = lower | upper; 155 dst[k + off] = lower | upper;
156 } 156 }
157 if (off) 157 if (off)
158 memset(dst, 0, off*sizeof(unsi 158 memset(dst, 0, off*sizeof(unsigned long));
159 } 159 }
160 EXPORT_SYMBOL(__bitmap_shift_left); 160 EXPORT_SYMBOL(__bitmap_shift_left);
161 161
162 /** 162 /**
163 * bitmap_cut() - remove bit region from bitma 163 * bitmap_cut() - remove bit region from bitmap and right shift remaining bits
164 * @dst: destination bitmap, might overlap wit 164 * @dst: destination bitmap, might overlap with src
165 * @src: source bitmap 165 * @src: source bitmap
166 * @first: start bit of region to be removed 166 * @first: start bit of region to be removed
167 * @cut: number of bits to remove 167 * @cut: number of bits to remove
168 * @nbits: bitmap size, in bits 168 * @nbits: bitmap size, in bits
169 * 169 *
170 * Set the n-th bit of @dst iff the n-th bit o 170 * Set the n-th bit of @dst iff the n-th bit of @src is set and
171 * n is less than @first, or the m-th bit of @ 171 * n is less than @first, or the m-th bit of @src is set for any
172 * m such that @first <= n < nbits, and m = n 172 * m such that @first <= n < nbits, and m = n + @cut.
173 * 173 *
174 * In pictures, example for a big-endian 32-bi 174 * In pictures, example for a big-endian 32-bit architecture:
175 * 175 *
176 * The @src bitmap is:: 176 * The @src bitmap is::
177 * 177 *
178 * 31 63 178 * 31 63
179 * | | 179 * | |
180 * 10000000 11000001 11110010 00010101 1000 180 * 10000000 11000001 11110010 00010101 10000000 11000001 01110010 00010101
181 * | | | 181 * | | | |
182 * 16 14 0 182 * 16 14 0 32
183 * 183 *
184 * if @cut is 3, and @first is 14, bits 14-16 184 * if @cut is 3, and @first is 14, bits 14-16 in @src are cut and @dst is::
185 * 185 *
186 * 31 63 186 * 31 63
187 * | | 187 * | |
188 * 10110000 00011000 00110010 00010101 0001 188 * 10110000 00011000 00110010 00010101 00010000 00011000 00101110 01000010
189 * | | 189 * | | |
190 * 14 (bit 17 0 190 * 14 (bit 17 0 32
191 * from @src) 191 * from @src)
192 * 192 *
193 * Note that @dst and @src might overlap parti 193 * Note that @dst and @src might overlap partially or entirely.
194 * 194 *
195 * This is implemented in the obvious way, wit 195 * This is implemented in the obvious way, with a shift and carry
196 * step for each moved bit. Optimisation is le 196 * step for each moved bit. Optimisation is left as an exercise
197 * for the compiler. 197 * for the compiler.
198 */ 198 */
199 void bitmap_cut(unsigned long *dst, const unsi 199 void bitmap_cut(unsigned long *dst, const unsigned long *src,
200 unsigned int first, unsigned i 200 unsigned int first, unsigned int cut, unsigned int nbits)
201 { 201 {
202 unsigned int len = BITS_TO_LONGS(nbits 202 unsigned int len = BITS_TO_LONGS(nbits);
203 unsigned long keep = 0, carry; 203 unsigned long keep = 0, carry;
204 int i; 204 int i;
205 205
206 if (first % BITS_PER_LONG) { 206 if (first % BITS_PER_LONG) {
207 keep = src[first / BITS_PER_LO 207 keep = src[first / BITS_PER_LONG] &
208 (~0UL >> (BITS_PER_LONG 208 (~0UL >> (BITS_PER_LONG - first % BITS_PER_LONG));
209 } 209 }
210 210
211 memmove(dst, src, len * sizeof(*dst)); 211 memmove(dst, src, len * sizeof(*dst));
212 212
213 while (cut--) { 213 while (cut--) {
214 for (i = first / BITS_PER_LONG 214 for (i = first / BITS_PER_LONG; i < len; i++) {
215 if (i < len - 1) 215 if (i < len - 1)
216 carry = dst[i 216 carry = dst[i + 1] & 1UL;
217 else 217 else
218 carry = 0; 218 carry = 0;
219 219
220 dst[i] = (dst[i] >> 1) 220 dst[i] = (dst[i] >> 1) | (carry << (BITS_PER_LONG - 1));
221 } 221 }
222 } 222 }
223 223
224 dst[first / BITS_PER_LONG] &= ~0UL << 224 dst[first / BITS_PER_LONG] &= ~0UL << (first % BITS_PER_LONG);
225 dst[first / BITS_PER_LONG] |= keep; 225 dst[first / BITS_PER_LONG] |= keep;
226 } 226 }
227 EXPORT_SYMBOL(bitmap_cut); 227 EXPORT_SYMBOL(bitmap_cut);
228 228
229 bool __bitmap_and(unsigned long *dst, const un 229 bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
230 const unsigned 230 const unsigned long *bitmap2, unsigned int bits)
231 { 231 {
232 unsigned int k; 232 unsigned int k;
233 unsigned int lim = bits/BITS_PER_LONG; 233 unsigned int lim = bits/BITS_PER_LONG;
234 unsigned long result = 0; 234 unsigned long result = 0;
235 235
236 for (k = 0; k < lim; k++) 236 for (k = 0; k < lim; k++)
237 result |= (dst[k] = bitmap1[k] 237 result |= (dst[k] = bitmap1[k] & bitmap2[k]);
238 if (bits % BITS_PER_LONG) 238 if (bits % BITS_PER_LONG)
239 result |= (dst[k] = bitmap1[k] 239 result |= (dst[k] = bitmap1[k] & bitmap2[k] &
240 BITMAP_LAST_WORD_MA 240 BITMAP_LAST_WORD_MASK(bits));
241 return result != 0; 241 return result != 0;
242 } 242 }
243 EXPORT_SYMBOL(__bitmap_and); 243 EXPORT_SYMBOL(__bitmap_and);
244 244
245 void __bitmap_or(unsigned long *dst, const uns 245 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
246 const unsigned 246 const unsigned long *bitmap2, unsigned int bits)
247 { 247 {
248 unsigned int k; 248 unsigned int k;
249 unsigned int nr = BITS_TO_LONGS(bits); 249 unsigned int nr = BITS_TO_LONGS(bits);
250 250
251 for (k = 0; k < nr; k++) 251 for (k = 0; k < nr; k++)
252 dst[k] = bitmap1[k] | bitmap2[ 252 dst[k] = bitmap1[k] | bitmap2[k];
253 } 253 }
254 EXPORT_SYMBOL(__bitmap_or); 254 EXPORT_SYMBOL(__bitmap_or);
255 255
256 void __bitmap_xor(unsigned long *dst, const un 256 void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
257 const unsigned 257 const unsigned long *bitmap2, unsigned int bits)
258 { 258 {
259 unsigned int k; 259 unsigned int k;
260 unsigned int nr = BITS_TO_LONGS(bits); 260 unsigned int nr = BITS_TO_LONGS(bits);
261 261
262 for (k = 0; k < nr; k++) 262 for (k = 0; k < nr; k++)
263 dst[k] = bitmap1[k] ^ bitmap2[ 263 dst[k] = bitmap1[k] ^ bitmap2[k];
264 } 264 }
265 EXPORT_SYMBOL(__bitmap_xor); 265 EXPORT_SYMBOL(__bitmap_xor);
266 266
267 bool __bitmap_andnot(unsigned long *dst, const 267 bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
268 const unsigned 268 const unsigned long *bitmap2, unsigned int bits)
269 { 269 {
270 unsigned int k; 270 unsigned int k;
271 unsigned int lim = bits/BITS_PER_LONG; 271 unsigned int lim = bits/BITS_PER_LONG;
272 unsigned long result = 0; 272 unsigned long result = 0;
273 273
274 for (k = 0; k < lim; k++) 274 for (k = 0; k < lim; k++)
275 result |= (dst[k] = bitmap1[k] 275 result |= (dst[k] = bitmap1[k] & ~bitmap2[k]);
276 if (bits % BITS_PER_LONG) 276 if (bits % BITS_PER_LONG)
277 result |= (dst[k] = bitmap1[k] 277 result |= (dst[k] = bitmap1[k] & ~bitmap2[k] &
278 BITMAP_LAST_WORD_MA 278 BITMAP_LAST_WORD_MASK(bits));
279 return result != 0; 279 return result != 0;
280 } 280 }
281 EXPORT_SYMBOL(__bitmap_andnot); 281 EXPORT_SYMBOL(__bitmap_andnot);
282 282
283 void __bitmap_replace(unsigned long *dst, 283 void __bitmap_replace(unsigned long *dst,
284 const unsigned long *old 284 const unsigned long *old, const unsigned long *new,
285 const unsigned long *mas 285 const unsigned long *mask, unsigned int nbits)
286 { 286 {
287 unsigned int k; 287 unsigned int k;
288 unsigned int nr = BITS_TO_LONGS(nbits) 288 unsigned int nr = BITS_TO_LONGS(nbits);
289 289
290 for (k = 0; k < nr; k++) 290 for (k = 0; k < nr; k++)
291 dst[k] = (old[k] & ~mask[k]) | 291 dst[k] = (old[k] & ~mask[k]) | (new[k] & mask[k]);
292 } 292 }
293 EXPORT_SYMBOL(__bitmap_replace); 293 EXPORT_SYMBOL(__bitmap_replace);
294 294
295 bool __bitmap_intersects(const unsigned long * 295 bool __bitmap_intersects(const unsigned long *bitmap1,
296 const unsigned long * 296 const unsigned long *bitmap2, unsigned int bits)
297 { 297 {
298 unsigned int k, lim = bits/BITS_PER_LO 298 unsigned int k, lim = bits/BITS_PER_LONG;
299 for (k = 0; k < lim; ++k) 299 for (k = 0; k < lim; ++k)
300 if (bitmap1[k] & bitmap2[k]) 300 if (bitmap1[k] & bitmap2[k])
301 return true; 301 return true;
302 302
303 if (bits % BITS_PER_LONG) 303 if (bits % BITS_PER_LONG)
304 if ((bitmap1[k] & bitmap2[k]) 304 if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
305 return true; 305 return true;
306 return false; 306 return false;
307 } 307 }
308 EXPORT_SYMBOL(__bitmap_intersects); 308 EXPORT_SYMBOL(__bitmap_intersects);
309 309
310 bool __bitmap_subset(const unsigned long *bitm 310 bool __bitmap_subset(const unsigned long *bitmap1,
311 const unsigned long *bitm 311 const unsigned long *bitmap2, unsigned int bits)
312 { 312 {
313 unsigned int k, lim = bits/BITS_PER_LO 313 unsigned int k, lim = bits/BITS_PER_LONG;
314 for (k = 0; k < lim; ++k) 314 for (k = 0; k < lim; ++k)
315 if (bitmap1[k] & ~bitmap2[k]) 315 if (bitmap1[k] & ~bitmap2[k])
316 return false; 316 return false;
317 317
318 if (bits % BITS_PER_LONG) 318 if (bits % BITS_PER_LONG)
319 if ((bitmap1[k] & ~bitmap2[k]) 319 if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
320 return false; 320 return false;
321 return true; 321 return true;
322 } 322 }
323 EXPORT_SYMBOL(__bitmap_subset); 323 EXPORT_SYMBOL(__bitmap_subset);
324 324
325 #define BITMAP_WEIGHT(FETCH, bits) \ 325 #define BITMAP_WEIGHT(FETCH, bits) \
326 ({ 326 ({ \
327 unsigned int __bits = (bits), idx, w = 327 unsigned int __bits = (bits), idx, w = 0; \
328 328 \
329 for (idx = 0; idx < __bits / BITS_PER_ 329 for (idx = 0; idx < __bits / BITS_PER_LONG; idx++) \
330 w += hweight_long(FETCH); 330 w += hweight_long(FETCH); \
331 331 \
332 if (__bits % BITS_PER_LONG) 332 if (__bits % BITS_PER_LONG) \
333 w += hweight_long((FETCH) & BI 333 w += hweight_long((FETCH) & BITMAP_LAST_WORD_MASK(__bits)); \
334 334 \
335 w; 335 w; \
336 }) 336 })
337 337
338 unsigned int __bitmap_weight(const unsigned lo 338 unsigned int __bitmap_weight(const unsigned long *bitmap, unsigned int bits)
339 { 339 {
340 return BITMAP_WEIGHT(bitmap[idx], bits 340 return BITMAP_WEIGHT(bitmap[idx], bits);
341 } 341 }
342 EXPORT_SYMBOL(__bitmap_weight); 342 EXPORT_SYMBOL(__bitmap_weight);
343 343
344 unsigned int __bitmap_weight_and(const unsigne 344 unsigned int __bitmap_weight_and(const unsigned long *bitmap1,
345 const unsigned 345 const unsigned long *bitmap2, unsigned int bits)
346 { 346 {
347 return BITMAP_WEIGHT(bitmap1[idx] & bi 347 return BITMAP_WEIGHT(bitmap1[idx] & bitmap2[idx], bits);
348 } 348 }
349 EXPORT_SYMBOL(__bitmap_weight_and); 349 EXPORT_SYMBOL(__bitmap_weight_and);
350 350
351 unsigned int __bitmap_weight_andnot(const unsi <<
352 const unsigned <<
353 { <<
354 return BITMAP_WEIGHT(bitmap1[idx] & ~b <<
355 } <<
356 EXPORT_SYMBOL(__bitmap_weight_andnot); <<
357 <<
358 void __bitmap_set(unsigned long *map, unsigned 351 void __bitmap_set(unsigned long *map, unsigned int start, int len)
359 { 352 {
360 unsigned long *p = map + BIT_WORD(star 353 unsigned long *p = map + BIT_WORD(start);
361 const unsigned int size = start + len; 354 const unsigned int size = start + len;
362 int bits_to_set = BITS_PER_LONG - (sta 355 int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
363 unsigned long mask_to_set = BITMAP_FIR 356 unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
364 357
365 while (len - bits_to_set >= 0) { 358 while (len - bits_to_set >= 0) {
366 *p |= mask_to_set; 359 *p |= mask_to_set;
367 len -= bits_to_set; 360 len -= bits_to_set;
368 bits_to_set = BITS_PER_LONG; 361 bits_to_set = BITS_PER_LONG;
369 mask_to_set = ~0UL; 362 mask_to_set = ~0UL;
370 p++; 363 p++;
371 } 364 }
372 if (len) { 365 if (len) {
373 mask_to_set &= BITMAP_LAST_WOR 366 mask_to_set &= BITMAP_LAST_WORD_MASK(size);
374 *p |= mask_to_set; 367 *p |= mask_to_set;
375 } 368 }
376 } 369 }
377 EXPORT_SYMBOL(__bitmap_set); 370 EXPORT_SYMBOL(__bitmap_set);
378 371
379 void __bitmap_clear(unsigned long *map, unsign 372 void __bitmap_clear(unsigned long *map, unsigned int start, int len)
380 { 373 {
381 unsigned long *p = map + BIT_WORD(star 374 unsigned long *p = map + BIT_WORD(start);
382 const unsigned int size = start + len; 375 const unsigned int size = start + len;
383 int bits_to_clear = BITS_PER_LONG - (s 376 int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
384 unsigned long mask_to_clear = BITMAP_F 377 unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
385 378
386 while (len - bits_to_clear >= 0) { 379 while (len - bits_to_clear >= 0) {
387 *p &= ~mask_to_clear; 380 *p &= ~mask_to_clear;
388 len -= bits_to_clear; 381 len -= bits_to_clear;
389 bits_to_clear = BITS_PER_LONG; 382 bits_to_clear = BITS_PER_LONG;
390 mask_to_clear = ~0UL; 383 mask_to_clear = ~0UL;
391 p++; 384 p++;
392 } 385 }
393 if (len) { 386 if (len) {
394 mask_to_clear &= BITMAP_LAST_W 387 mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
395 *p &= ~mask_to_clear; 388 *p &= ~mask_to_clear;
396 } 389 }
397 } 390 }
398 EXPORT_SYMBOL(__bitmap_clear); 391 EXPORT_SYMBOL(__bitmap_clear);
399 392
400 /** 393 /**
401 * bitmap_find_next_zero_area_off - find a con 394 * bitmap_find_next_zero_area_off - find a contiguous aligned zero area
402 * @map: The address to base the search on 395 * @map: The address to base the search on
403 * @size: The bitmap size in bits 396 * @size: The bitmap size in bits
404 * @start: The bitnumber to start searching at 397 * @start: The bitnumber to start searching at
405 * @nr: The number of zeroed bits we're lookin 398 * @nr: The number of zeroed bits we're looking for
406 * @align_mask: Alignment mask for zero area 399 * @align_mask: Alignment mask for zero area
407 * @align_offset: Alignment offset for zero ar 400 * @align_offset: Alignment offset for zero area.
408 * 401 *
409 * The @align_mask should be one less than a p 402 * 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 403 * the bit offset of all zero areas this function finds plus @align_offset
411 * is multiple of that power of 2. 404 * is multiple of that power of 2.
412 */ 405 */
413 unsigned long bitmap_find_next_zero_area_off(u 406 unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
414 u 407 unsigned long size,
415 u 408 unsigned long start,
416 u 409 unsigned int nr,
417 u 410 unsigned long align_mask,
418 u 411 unsigned long align_offset)
419 { 412 {
420 unsigned long index, end, i; 413 unsigned long index, end, i;
421 again: 414 again:
422 index = find_next_zero_bit(map, size, 415 index = find_next_zero_bit(map, size, start);
423 416
424 /* Align allocation */ 417 /* Align allocation */
425 index = __ALIGN_MASK(index + align_off 418 index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset;
426 419
427 end = index + nr; 420 end = index + nr;
428 if (end > size) 421 if (end > size)
429 return end; 422 return end;
430 i = find_next_bit(map, end, index); 423 i = find_next_bit(map, end, index);
431 if (i < end) { 424 if (i < end) {
432 start = i + 1; 425 start = i + 1;
433 goto again; 426 goto again;
434 } 427 }
435 return index; 428 return index;
436 } 429 }
437 EXPORT_SYMBOL(bitmap_find_next_zero_area_off); 430 EXPORT_SYMBOL(bitmap_find_next_zero_area_off);
438 431
439 /** 432 /**
440 * bitmap_pos_to_ord - find ordinal of set bit 433 * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap
441 * @buf: pointer to a bitmap 434 * @buf: pointer to a bitmap
442 * @pos: a bit position in @buf (0 <= @po 435 * @pos: a bit position in @buf (0 <= @pos < @nbits)
443 * @nbits: number of valid bit positions 436 * @nbits: number of valid bit positions in @buf
444 * 437 *
445 * Map the bit at position @pos in @buf (of le 438 * 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 439 * 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. 440 * is not a valid bit position, map to -1.
448 * 441 *
449 * If for example, just bits 4 through 7 are s 442 * 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 443 * values 4 through 7 will get mapped to 0 through 3, respectively,
451 * and other @pos values will get mapped to -1 444 * and other @pos values will get mapped to -1. When @pos value 7
452 * gets mapped to (returns) @ord value 3 in th 445 * gets mapped to (returns) @ord value 3 in this example, that means
453 * that bit 7 is the 3rd (starting with 0th) s 446 * that bit 7 is the 3rd (starting with 0th) set bit in @buf.
454 * 447 *
455 * The bit positions 0 through @bits are valid 448 * The bit positions 0 through @bits are valid positions in @buf.
456 */ 449 */
457 static int bitmap_pos_to_ord(const unsigned lo 450 static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits)
458 { 451 {
459 if (pos >= nbits || !test_bit(pos, buf 452 if (pos >= nbits || !test_bit(pos, buf))
460 return -1; 453 return -1;
461 454
462 return bitmap_weight(buf, pos); 455 return bitmap_weight(buf, pos);
463 } 456 }
464 457
465 /** 458 /**
466 * bitmap_remap - Apply map defined by a pair 459 * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap
467 * @dst: remapped result 460 * @dst: remapped result
468 * @src: subset to be remapped 461 * @src: subset to be remapped
469 * @old: defines domain of map 462 * @old: defines domain of map
470 * @new: defines range of map 463 * @new: defines range of map
471 * @nbits: number of bits in each of thes 464 * @nbits: number of bits in each of these bitmaps
472 * 465 *
473 * Let @old and @new define a mapping of bit p 466 * Let @old and @new define a mapping of bit positions, such that
474 * whatever position is held by the n-th set b 467 * 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 468 * to the n-th set bit in @new. In the more general case, allowing
476 * for the possibility that the weight 'w' of 469 * for the possibility that the weight 'w' of @new is less than the
477 * weight of @old, map the position of the n-t 470 * 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 471 * the position of the m-th set bit in @new, where m == n % w.
479 * 472 *
480 * If either of the @old and @new bitmaps are 473 * If either of the @old and @new bitmaps are empty, or if @src and
481 * @dst point to the same location, then this 474 * @dst point to the same location, then this routine copies @src
482 * to @dst. 475 * to @dst.
483 * 476 *
484 * The positions of unset bits in @old are map 477 * The positions of unset bits in @old are mapped to themselves
485 * (the identity map). 478 * (the identity map).
486 * 479 *
487 * Apply the above specified mapping to @src, 480 * Apply the above specified mapping to @src, placing the result in
488 * @dst, clearing any bits previously set in @ 481 * @dst, clearing any bits previously set in @dst.
489 * 482 *
490 * For example, lets say that @old has bits 4 483 * For example, lets say that @old has bits 4 through 7 set, and
491 * @new has bits 12 through 15 set. This defi 484 * @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 485 * 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 486 * bit positions unchanged. So if say @src comes into this routine
494 * with bits 1, 5 and 7 set, then @dst should 487 * with bits 1, 5 and 7 set, then @dst should leave with bits 1,
495 * 13 and 15 set. 488 * 13 and 15 set.
496 */ 489 */
497 void bitmap_remap(unsigned long *dst, const un 490 void bitmap_remap(unsigned long *dst, const unsigned long *src,
498 const unsigned long *old, cons 491 const unsigned long *old, const unsigned long *new,
499 unsigned int nbits) 492 unsigned int nbits)
500 { 493 {
501 unsigned int oldbit, w; 494 unsigned int oldbit, w;
502 495
503 if (dst == src) /* following d 496 if (dst == src) /* following doesn't handle inplace remaps */
504 return; 497 return;
505 bitmap_zero(dst, nbits); 498 bitmap_zero(dst, nbits);
506 499
507 w = bitmap_weight(new, nbits); 500 w = bitmap_weight(new, nbits);
508 for_each_set_bit(oldbit, src, nbits) { 501 for_each_set_bit(oldbit, src, nbits) {
509 int n = bitmap_pos_to_ord(old, 502 int n = bitmap_pos_to_ord(old, oldbit, nbits);
510 503
511 if (n < 0 || w == 0) 504 if (n < 0 || w == 0)
512 set_bit(oldbit, dst); 505 set_bit(oldbit, dst); /* identity map */
513 else 506 else
514 set_bit(find_nth_bit(n 507 set_bit(find_nth_bit(new, nbits, n % w), dst);
515 } 508 }
516 } 509 }
517 EXPORT_SYMBOL(bitmap_remap); 510 EXPORT_SYMBOL(bitmap_remap);
518 511
519 /** 512 /**
520 * bitmap_bitremap - Apply map defined by a pa 513 * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit
521 * @oldbit: bit position to be mapped 514 * @oldbit: bit position to be mapped
522 * @old: defines domain of map 515 * @old: defines domain of map
523 * @new: defines range of map 516 * @new: defines range of map
524 * @bits: number of bits in each of these 517 * @bits: number of bits in each of these bitmaps
525 * 518 *
526 * Let @old and @new define a mapping of bit p 519 * Let @old and @new define a mapping of bit positions, such that
527 * whatever position is held by the n-th set b 520 * 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 521 * to the n-th set bit in @new. In the more general case, allowing
529 * for the possibility that the weight 'w' of 522 * for the possibility that the weight 'w' of @new is less than the
530 * weight of @old, map the position of the n-t 523 * 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 524 * the position of the m-th set bit in @new, where m == n % w.
532 * 525 *
533 * The positions of unset bits in @old are map 526 * The positions of unset bits in @old are mapped to themselves
534 * (the identity map). 527 * (the identity map).
535 * 528 *
536 * Apply the above specified mapping to bit po 529 * Apply the above specified mapping to bit position @oldbit, returning
537 * the new bit position. 530 * the new bit position.
538 * 531 *
539 * For example, lets say that @old has bits 4 532 * For example, lets say that @old has bits 4 through 7 set, and
540 * @new has bits 12 through 15 set. This defi 533 * @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 534 * 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 535 * bit positions unchanged. So if say @oldbit is 5, then this routine
543 * returns 13. 536 * returns 13.
544 */ 537 */
545 int bitmap_bitremap(int oldbit, const unsigned 538 int bitmap_bitremap(int oldbit, const unsigned long *old,
546 const unsigned 539 const unsigned long *new, int bits)
547 { 540 {
548 int w = bitmap_weight(new, bits); 541 int w = bitmap_weight(new, bits);
549 int n = bitmap_pos_to_ord(old, oldbit, 542 int n = bitmap_pos_to_ord(old, oldbit, bits);
550 if (n < 0 || w == 0) 543 if (n < 0 || w == 0)
551 return oldbit; 544 return oldbit;
552 else 545 else
553 return find_nth_bit(new, bits, 546 return find_nth_bit(new, bits, n % w);
554 } 547 }
555 EXPORT_SYMBOL(bitmap_bitremap); 548 EXPORT_SYMBOL(bitmap_bitremap);
556 549
557 #ifdef CONFIG_NUMA 550 #ifdef CONFIG_NUMA
558 /** 551 /**
559 * bitmap_onto - translate one bitmap relative 552 * bitmap_onto - translate one bitmap relative to another
560 * @dst: resulting translated bitmap 553 * @dst: resulting translated bitmap
561 * @orig: original untranslated bitmap 554 * @orig: original untranslated bitmap
562 * @relmap: bitmap relative to which tran 555 * @relmap: bitmap relative to which translated
563 * @bits: number of bits in each of these 556 * @bits: number of bits in each of these bitmaps
564 * 557 *
565 * Set the n-th bit of @dst iff there exists s 558 * 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 559 * 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 560 * the n-th bit of @relmap is also the m-th _set_ bit of @relmap.
568 * (If you understood the previous sentence th 561 * (If you understood the previous sentence the first time your
569 * read it, you're overqualified for your curr 562 * read it, you're overqualified for your current job.)
570 * 563 *
571 * In other words, @orig is mapped onto (surje 564 * In other words, @orig is mapped onto (surjectively) @dst,
572 * using the map { <n, m> | the n-th bit of @r 565 * using the map { <n, m> | the n-th bit of @relmap is the
573 * m-th set bit of @relmap }. 566 * m-th set bit of @relmap }.
574 * 567 *
575 * Any set bits in @orig above bit number W, w 568 * Any set bits in @orig above bit number W, where W is the
576 * weight of (number of set bits in) @relmap a 569 * weight of (number of set bits in) @relmap are mapped nowhere.
577 * In particular, if for all bits m set in @or 570 * In particular, if for all bits m set in @orig, m >= W, then
578 * @dst will end up empty. In situations wher 571 * @dst will end up empty. In situations where the possibility
579 * of such an empty result is not desired, one 572 * of such an empty result is not desired, one way to avoid it is
580 * to use the bitmap_fold() operator, below, t 573 * to use the bitmap_fold() operator, below, to first fold the
581 * @orig bitmap over itself so that all its se 574 * @orig bitmap over itself so that all its set bits x are in the
582 * range 0 <= x < W. The bitmap_fold() operat 575 * range 0 <= x < W. The bitmap_fold() operator does this by
583 * setting the bit (m % W) in @dst, for each b 576 * setting the bit (m % W) in @dst, for each bit (m) set in @orig.
584 * 577 *
585 * Example [1] for bitmap_onto(): 578 * Example [1] for bitmap_onto():
586 * Let's say @relmap has bits 30-39 set, and 579 * 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 580 * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine,
588 * @dst will have bits 31, 33, 35, 37 and 39 581 * @dst will have bits 31, 33, 35, 37 and 39 set.
589 * 582 *
590 * When bit 0 is set in @orig, it means turn 583 * When bit 0 is set in @orig, it means turn on the bit in
591 * @dst corresponding to whatever is the firs 584 * @dst corresponding to whatever is the first bit (if any)
592 * that is turned on in @relmap. Since bit 0 585 * that is turned on in @relmap. Since bit 0 was off in the
593 * above example, we leave off that bit (bit 586 * above example, we leave off that bit (bit 30) in @dst.
594 * 587 *
595 * When bit 1 is set in @orig (as in the abov 588 * When bit 1 is set in @orig (as in the above example), it
596 * means turn on the bit in @dst correspondin 589 * means turn on the bit in @dst corresponding to whatever
597 * is the second bit that is turned on in @re 590 * is the second bit that is turned on in @relmap. The second
598 * bit in @relmap that was turned on in the a 591 * bit in @relmap that was turned on in the above example was
599 * bit 31, so we turned on bit 31 in @dst. 592 * bit 31, so we turned on bit 31 in @dst.
600 * 593 *
601 * Similarly, we turned on bits 33, 35, 37 an 594 * Similarly, we turned on bits 33, 35, 37 and 39 in @dst,
602 * because they were the 4th, 6th, 8th and 10 595 * because they were the 4th, 6th, 8th and 10th set bits
603 * set in @relmap, and the 4th, 6th, 8th and 596 * set in @relmap, and the 4th, 6th, 8th and 10th bits of
604 * @orig (i.e. bits 3, 5, 7 and 9) were also 597 * @orig (i.e. bits 3, 5, 7 and 9) were also set.
605 * 598 *
606 * When bit 11 is set in @orig, it means turn 599 * When bit 11 is set in @orig, it means turn on the bit in
607 * @dst corresponding to whatever is the twel 600 * @dst corresponding to whatever is the twelfth bit that is
608 * turned on in @relmap. In the above exampl 601 * turned on in @relmap. In the above example, there were
609 * only ten bits turned on in @relmap (30..39 602 * only ten bits turned on in @relmap (30..39), so that bit
610 * 11 was set in @orig had no affect on @dst. 603 * 11 was set in @orig had no affect on @dst.
611 * 604 *
612 * Example [2] for bitmap_fold() + bitmap_onto 605 * Example [2] for bitmap_fold() + bitmap_onto():
613 * Let's say @relmap has these ten bits set:: 606 * Let's say @relmap has these ten bits set::
614 * 607 *
615 * 40 41 42 43 45 48 53 61 74 95 608 * 40 41 42 43 45 48 53 61 74 95
616 * 609 *
617 * (for the curious, that's 40 plus the first 610 * (for the curious, that's 40 plus the first ten terms of the
618 * Fibonacci sequence.) 611 * Fibonacci sequence.)
619 * 612 *
620 * Further lets say we use the following code 613 * Further lets say we use the following code, invoking
621 * bitmap_fold() then bitmap_onto, as suggest 614 * bitmap_fold() then bitmap_onto, as suggested above to
622 * avoid the possibility of an empty @dst res 615 * avoid the possibility of an empty @dst result::
623 * 616 *
624 * unsigned long *tmp; // a temporary 617 * unsigned long *tmp; // a temporary bitmap's bits
625 * 618 *
626 * bitmap_fold(tmp, orig, bitmap_weight(r 619 * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits);
627 * bitmap_onto(dst, tmp, relmap, bits); 620 * bitmap_onto(dst, tmp, relmap, bits);
628 * 621 *
629 * Then this table shows what various values 622 * Then this table shows what various values of @dst would be, for
630 * various @orig's. I list the zero-based po 623 * various @orig's. I list the zero-based positions of each set bit.
631 * The tmp column shows the intermediate resu 624 * The tmp column shows the intermediate result, as computed by
632 * using bitmap_fold() to fold the @orig bitm 625 * using bitmap_fold() to fold the @orig bitmap modulo ten
633 * (the weight of @relmap): 626 * (the weight of @relmap):
634 * 627 *
635 * =============== ============== ======= 628 * =============== ============== =================
636 * @orig tmp @dst 629 * @orig tmp @dst
637 * 0 0 40 630 * 0 0 40
638 * 1 1 41 631 * 1 1 41
639 * 9 9 95 632 * 9 9 95
640 * 10 0 40 [#f1 633 * 10 0 40 [#f1]_
641 * 1 3 5 7 1 3 5 7 41 43 4 634 * 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 4 635 * 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 7 636 * 0 9 18 27 0 9 8 7 40 61 74 95
644 * 0 10 20 30 0 40 637 * 0 10 20 30 0 40
645 * 0 11 22 33 0 1 2 3 40 41 4 638 * 0 11 22 33 0 1 2 3 40 41 42 43
646 * 0 12 24 36 0 2 4 6 40 42 4 639 * 0 12 24 36 0 2 4 6 40 42 45 53
647 * 78 102 211 1 2 8 41 42 7 640 * 78 102 211 1 2 8 41 42 74 [#f1]_
648 * =============== ============== ======= 641 * =============== ============== =================
649 * 642 *
650 * .. [#f1] 643 * .. [#f1]
651 * 644 *
652 * For these marked lines, if we hadn't fi 645 * For these marked lines, if we hadn't first done bitmap_fold()
653 * into tmp, then the @dst result would ha 646 * into tmp, then the @dst result would have been empty.
654 * 647 *
655 * If either of @orig or @relmap is empty (no 648 * If either of @orig or @relmap is empty (no set bits), then @dst
656 * will be returned empty. 649 * will be returned empty.
657 * 650 *
658 * If (as explained above) the only set bits i 651 * If (as explained above) the only set bits in @orig are in positions
659 * m where m >= W, (where W is the weight of @ 652 * m where m >= W, (where W is the weight of @relmap) then @dst will
660 * once again be returned empty. 653 * once again be returned empty.
661 * 654 *
662 * All bits in @dst not set by the above rule 655 * All bits in @dst not set by the above rule are cleared.
663 */ 656 */
664 void bitmap_onto(unsigned long *dst, const uns 657 void bitmap_onto(unsigned long *dst, const unsigned long *orig,
665 const unsigned long *r 658 const unsigned long *relmap, unsigned int bits)
666 { 659 {
667 unsigned int n, m; /* same meanin 660 unsigned int n, m; /* same meaning as in above comment */
668 661
669 if (dst == orig) /* following d 662 if (dst == orig) /* following doesn't handle inplace mappings */
670 return; 663 return;
671 bitmap_zero(dst, bits); 664 bitmap_zero(dst, bits);
672 665
673 /* 666 /*
674 * The following code is a more effici 667 * The following code is a more efficient, but less
675 * obvious, equivalent to the loop: 668 * obvious, equivalent to the loop:
676 * for (m = 0; m < bitmap_weight( 669 * for (m = 0; m < bitmap_weight(relmap, bits); m++) {
677 * n = find_nth_bit(orig, 670 * n = find_nth_bit(orig, bits, m);
678 * if (test_bit(m, orig)) 671 * if (test_bit(m, orig))
679 * set_bit(n, dst 672 * set_bit(n, dst);
680 * } 673 * }
681 */ 674 */
682 675
683 m = 0; 676 m = 0;
684 for_each_set_bit(n, relmap, bits) { 677 for_each_set_bit(n, relmap, bits) {
685 /* m == bitmap_pos_to_ord(relm 678 /* m == bitmap_pos_to_ord(relmap, n, bits) */
686 if (test_bit(m, orig)) 679 if (test_bit(m, orig))
687 set_bit(n, dst); 680 set_bit(n, dst);
688 m++; 681 m++;
689 } 682 }
690 } 683 }
691 684
692 /** 685 /**
693 * bitmap_fold - fold larger bitmap into small 686 * bitmap_fold - fold larger bitmap into smaller, modulo specified size
694 * @dst: resulting smaller bitmap 687 * @dst: resulting smaller bitmap
695 * @orig: original larger bitmap 688 * @orig: original larger bitmap
696 * @sz: specified size 689 * @sz: specified size
697 * @nbits: number of bits in each of thes 690 * @nbits: number of bits in each of these bitmaps
698 * 691 *
699 * For each bit oldbit in @orig, set bit oldbi 692 * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst.
700 * Clear all other bits in @dst. See further 693 * Clear all other bits in @dst. See further the comment and
701 * Example [2] for bitmap_onto() for why and h 694 * Example [2] for bitmap_onto() for why and how to use this.
702 */ 695 */
703 void bitmap_fold(unsigned long *dst, const uns 696 void bitmap_fold(unsigned long *dst, const unsigned long *orig,
704 unsigned int sz, unsig 697 unsigned int sz, unsigned int nbits)
705 { 698 {
706 unsigned int oldbit; 699 unsigned int oldbit;
707 700
708 if (dst == orig) /* following d 701 if (dst == orig) /* following doesn't handle inplace mappings */
709 return; 702 return;
710 bitmap_zero(dst, nbits); 703 bitmap_zero(dst, nbits);
711 704
712 for_each_set_bit(oldbit, orig, nbits) 705 for_each_set_bit(oldbit, orig, nbits)
713 set_bit(oldbit % sz, dst); 706 set_bit(oldbit % sz, dst);
714 } 707 }
715 #endif /* CONFIG_NUMA */ 708 #endif /* CONFIG_NUMA */
716 709
717 unsigned long *bitmap_alloc(unsigned int nbits 710 unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags)
718 { 711 {
719 return kmalloc_array(BITS_TO_LONGS(nbi 712 return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long),
720 flags); 713 flags);
721 } 714 }
722 EXPORT_SYMBOL(bitmap_alloc); 715 EXPORT_SYMBOL(bitmap_alloc);
723 716
724 unsigned long *bitmap_zalloc(unsigned int nbit 717 unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags)
725 { 718 {
726 return bitmap_alloc(nbits, flags | __G 719 return bitmap_alloc(nbits, flags | __GFP_ZERO);
727 } 720 }
728 EXPORT_SYMBOL(bitmap_zalloc); 721 EXPORT_SYMBOL(bitmap_zalloc);
729 722
730 unsigned long *bitmap_alloc_node(unsigned int 723 unsigned long *bitmap_alloc_node(unsigned int nbits, gfp_t flags, int node)
731 { 724 {
732 return kmalloc_array_node(BITS_TO_LONG 725 return kmalloc_array_node(BITS_TO_LONGS(nbits), sizeof(unsigned long),
733 flags, node) 726 flags, node);
734 } 727 }
735 EXPORT_SYMBOL(bitmap_alloc_node); 728 EXPORT_SYMBOL(bitmap_alloc_node);
736 729
737 unsigned long *bitmap_zalloc_node(unsigned int 730 unsigned long *bitmap_zalloc_node(unsigned int nbits, gfp_t flags, int node)
738 { 731 {
739 return bitmap_alloc_node(nbits, flags 732 return bitmap_alloc_node(nbits, flags | __GFP_ZERO, node);
740 } 733 }
741 EXPORT_SYMBOL(bitmap_zalloc_node); 734 EXPORT_SYMBOL(bitmap_zalloc_node);
742 735
743 void bitmap_free(const unsigned long *bitmap) 736 void bitmap_free(const unsigned long *bitmap)
744 { 737 {
745 kfree(bitmap); 738 kfree(bitmap);
746 } 739 }
747 EXPORT_SYMBOL(bitmap_free); 740 EXPORT_SYMBOL(bitmap_free);
748 741
749 static void devm_bitmap_free(void *data) 742 static void devm_bitmap_free(void *data)
750 { 743 {
751 unsigned long *bitmap = data; 744 unsigned long *bitmap = data;
752 745
753 bitmap_free(bitmap); 746 bitmap_free(bitmap);
754 } 747 }
755 748
756 unsigned long *devm_bitmap_alloc(struct device 749 unsigned long *devm_bitmap_alloc(struct device *dev,
757 unsigned int 750 unsigned int nbits, gfp_t flags)
758 { 751 {
759 unsigned long *bitmap; 752 unsigned long *bitmap;
760 int ret; 753 int ret;
761 754
762 bitmap = bitmap_alloc(nbits, flags); 755 bitmap = bitmap_alloc(nbits, flags);
763 if (!bitmap) 756 if (!bitmap)
764 return NULL; 757 return NULL;
765 758
766 ret = devm_add_action_or_reset(dev, de 759 ret = devm_add_action_or_reset(dev, devm_bitmap_free, bitmap);
767 if (ret) 760 if (ret)
768 return NULL; 761 return NULL;
769 762
770 return bitmap; 763 return bitmap;
771 } 764 }
772 EXPORT_SYMBOL_GPL(devm_bitmap_alloc); 765 EXPORT_SYMBOL_GPL(devm_bitmap_alloc);
773 766
774 unsigned long *devm_bitmap_zalloc(struct devic 767 unsigned long *devm_bitmap_zalloc(struct device *dev,
775 unsigned int 768 unsigned int nbits, gfp_t flags)
776 { 769 {
777 return devm_bitmap_alloc(dev, nbits, f 770 return devm_bitmap_alloc(dev, nbits, flags | __GFP_ZERO);
778 } 771 }
779 EXPORT_SYMBOL_GPL(devm_bitmap_zalloc); 772 EXPORT_SYMBOL_GPL(devm_bitmap_zalloc);
780 773
781 #if BITS_PER_LONG == 64 774 #if BITS_PER_LONG == 64
782 /** 775 /**
783 * bitmap_from_arr32 - copy the contents of u3 776 * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap
784 * @bitmap: array of unsigned longs, the 777 * @bitmap: array of unsigned longs, the destination bitmap
785 * @buf: array of u32 (in host byte order 778 * @buf: array of u32 (in host byte order), the source bitmap
786 * @nbits: number of bits in @bitmap 779 * @nbits: number of bits in @bitmap
787 */ 780 */
788 void bitmap_from_arr32(unsigned long *bitmap, 781 void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits)
789 { 782 {
790 unsigned int i, halfwords; 783 unsigned int i, halfwords;
791 784
792 halfwords = DIV_ROUND_UP(nbits, 32); 785 halfwords = DIV_ROUND_UP(nbits, 32);
793 for (i = 0; i < halfwords; i++) { 786 for (i = 0; i < halfwords; i++) {
794 bitmap[i/2] = (unsigned long) 787 bitmap[i/2] = (unsigned long) buf[i];
795 if (++i < halfwords) 788 if (++i < halfwords)
796 bitmap[i/2] |= ((unsig 789 bitmap[i/2] |= ((unsigned long) buf[i]) << 32;
797 } 790 }
798 791
799 /* Clear tail bits in last word beyond 792 /* Clear tail bits in last word beyond nbits. */
800 if (nbits % BITS_PER_LONG) 793 if (nbits % BITS_PER_LONG)
801 bitmap[(halfwords - 1) / 2] &= 794 bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits);
802 } 795 }
803 EXPORT_SYMBOL(bitmap_from_arr32); 796 EXPORT_SYMBOL(bitmap_from_arr32);
804 797
805 /** 798 /**
806 * bitmap_to_arr32 - copy the contents of bitm 799 * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits
807 * @buf: array of u32 (in host byte order 800 * @buf: array of u32 (in host byte order), the dest bitmap
808 * @bitmap: array of unsigned longs, the 801 * @bitmap: array of unsigned longs, the source bitmap
809 * @nbits: number of bits in @bitmap 802 * @nbits: number of bits in @bitmap
810 */ 803 */
811 void bitmap_to_arr32(u32 *buf, const unsigned 804 void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits)
812 { 805 {
813 unsigned int i, halfwords; 806 unsigned int i, halfwords;
814 807
815 halfwords = DIV_ROUND_UP(nbits, 32); 808 halfwords = DIV_ROUND_UP(nbits, 32);
816 for (i = 0; i < halfwords; i++) { 809 for (i = 0; i < halfwords; i++) {
817 buf[i] = (u32) (bitmap[i/2] & 810 buf[i] = (u32) (bitmap[i/2] & UINT_MAX);
818 if (++i < halfwords) 811 if (++i < halfwords)
819 buf[i] = (u32) (bitmap 812 buf[i] = (u32) (bitmap[i/2] >> 32);
820 } 813 }
821 814
822 /* Clear tail bits in last element of 815 /* Clear tail bits in last element of array beyond nbits. */
823 if (nbits % BITS_PER_LONG) 816 if (nbits % BITS_PER_LONG)
824 buf[halfwords - 1] &= (u32) (U 817 buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31));
825 } 818 }
826 EXPORT_SYMBOL(bitmap_to_arr32); 819 EXPORT_SYMBOL(bitmap_to_arr32);
827 #endif 820 #endif
828 821
829 #if BITS_PER_LONG == 32 822 #if BITS_PER_LONG == 32
830 /** 823 /**
831 * bitmap_from_arr64 - copy the contents of u6 824 * bitmap_from_arr64 - copy the contents of u64 array of bits to bitmap
832 * @bitmap: array of unsigned longs, the 825 * @bitmap: array of unsigned longs, the destination bitmap
833 * @buf: array of u64 (in host byte order 826 * @buf: array of u64 (in host byte order), the source bitmap
834 * @nbits: number of bits in @bitmap 827 * @nbits: number of bits in @bitmap
835 */ 828 */
836 void bitmap_from_arr64(unsigned long *bitmap, 829 void bitmap_from_arr64(unsigned long *bitmap, const u64 *buf, unsigned int nbits)
837 { 830 {
838 int n; 831 int n;
839 832
840 for (n = nbits; n > 0; n -= 64) { 833 for (n = nbits; n > 0; n -= 64) {
841 u64 val = *buf++; 834 u64 val = *buf++;
842 835
843 *bitmap++ = val; 836 *bitmap++ = val;
844 if (n > 32) 837 if (n > 32)
845 *bitmap++ = val >> 32; 838 *bitmap++ = val >> 32;
846 } 839 }
847 840
848 /* 841 /*
849 * Clear tail bits in the last word be 842 * Clear tail bits in the last word beyond nbits.
850 * 843 *
851 * Negative index is OK because here w 844 * Negative index is OK because here we point to the word next
852 * to the last word of the bitmap, exc 845 * to the last word of the bitmap, except for nbits == 0, which
853 * is tested implicitly. 846 * is tested implicitly.
854 */ 847 */
855 if (nbits % BITS_PER_LONG) 848 if (nbits % BITS_PER_LONG)
856 bitmap[-1] &= BITMAP_LAST_WORD 849 bitmap[-1] &= BITMAP_LAST_WORD_MASK(nbits);
857 } 850 }
858 EXPORT_SYMBOL(bitmap_from_arr64); 851 EXPORT_SYMBOL(bitmap_from_arr64);
859 852
860 /** 853 /**
861 * bitmap_to_arr64 - copy the contents of bitm 854 * bitmap_to_arr64 - copy the contents of bitmap to a u64 array of bits
862 * @buf: array of u64 (in host byte order 855 * @buf: array of u64 (in host byte order), the dest bitmap
863 * @bitmap: array of unsigned longs, the 856 * @bitmap: array of unsigned longs, the source bitmap
864 * @nbits: number of bits in @bitmap 857 * @nbits: number of bits in @bitmap
865 */ 858 */
866 void bitmap_to_arr64(u64 *buf, const unsigned 859 void bitmap_to_arr64(u64 *buf, const unsigned long *bitmap, unsigned int nbits)
867 { 860 {
868 const unsigned long *end = bitmap + BI 861 const unsigned long *end = bitmap + BITS_TO_LONGS(nbits);
869 862
870 while (bitmap < end) { 863 while (bitmap < end) {
871 *buf = *bitmap++; 864 *buf = *bitmap++;
872 if (bitmap < end) 865 if (bitmap < end)
873 *buf |= (u64)(*bitmap+ 866 *buf |= (u64)(*bitmap++) << 32;
874 buf++; 867 buf++;
875 } 868 }
876 869
877 /* Clear tail bits in the last element 870 /* Clear tail bits in the last element of array beyond nbits. */
878 if (nbits % 64) 871 if (nbits % 64)
879 buf[-1] &= GENMASK_ULL((nbits 872 buf[-1] &= GENMASK_ULL((nbits - 1) % 64, 0);
880 } 873 }
881 EXPORT_SYMBOL(bitmap_to_arr64); 874 EXPORT_SYMBOL(bitmap_to_arr64);
882 #endif 875 #endif
883 876
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