Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * lib/bitmap.c |
| 3 | * Helper functions for bitmap.h. |
| 4 | * |
| 5 | * This source code is licensed under the GNU General Public License, |
| 6 | * Version 2. See the file COPYING for more details. |
| 7 | */ |
Paul Gortmaker | 8bc3bcc | 2011-11-16 21:29:17 -0500 | [diff] [blame] | 8 | #include <linux/export.h> |
| 9 | #include <linux/thread_info.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/ctype.h> |
| 11 | #include <linux/errno.h> |
| 12 | #include <linux/bitmap.h> |
| 13 | #include <linux/bitops.h> |
Paul Gortmaker | 50af5ea | 2012-01-20 18:35:53 -0500 | [diff] [blame] | 14 | #include <linux/bug.h> |
Sudeep Holla | 5aaba36 | 2014-09-30 14:48:22 +0100 | [diff] [blame] | 15 | |
| 16 | #include <asm/page.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <asm/uaccess.h> |
| 18 | |
| 19 | /* |
| 20 | * bitmaps provide an array of bits, implemented using an an |
| 21 | * array of unsigned longs. The number of valid bits in a |
| 22 | * given bitmap does _not_ need to be an exact multiple of |
| 23 | * BITS_PER_LONG. |
| 24 | * |
| 25 | * The possible unused bits in the last, partially used word |
| 26 | * of a bitmap are 'don't care'. The implementation makes |
| 27 | * no particular effort to keep them zero. It ensures that |
| 28 | * their value will not affect the results of any operation. |
| 29 | * The bitmap operations that return Boolean (bitmap_empty, |
| 30 | * for example) or scalar (bitmap_weight, for example) results |
| 31 | * carefully filter out these unused bits from impacting their |
| 32 | * results. |
| 33 | * |
| 34 | * These operations actually hold to a slightly stronger rule: |
| 35 | * if you don't input any bitmaps to these ops that have some |
| 36 | * unused bits set, then they won't output any set unused bits |
| 37 | * in output bitmaps. |
| 38 | * |
| 39 | * The byte ordering of bitmaps is more natural on little |
| 40 | * endian architectures. See the big-endian headers |
| 41 | * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h |
| 42 | * for the best explanations of this ordering. |
| 43 | */ |
| 44 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | int __bitmap_equal(const unsigned long *bitmap1, |
Rasmus Villemoes | 5e068069 | 2014-08-06 16:09:53 -0700 | [diff] [blame] | 46 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | { |
Rasmus Villemoes | 5e068069 | 2014-08-06 16:09:53 -0700 | [diff] [blame] | 48 | unsigned int k, lim = bits/BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | for (k = 0; k < lim; ++k) |
| 50 | if (bitmap1[k] != bitmap2[k]) |
| 51 | return 0; |
| 52 | |
| 53 | if (bits % BITS_PER_LONG) |
| 54 | if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) |
| 55 | return 0; |
| 56 | |
| 57 | return 1; |
| 58 | } |
| 59 | EXPORT_SYMBOL(__bitmap_equal); |
| 60 | |
Rasmus Villemoes | 3d6684f | 2014-08-06 16:09:55 -0700 | [diff] [blame] | 61 | void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | { |
Rasmus Villemoes | 3d6684f | 2014-08-06 16:09:55 -0700 | [diff] [blame] | 63 | unsigned int k, lim = bits/BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | for (k = 0; k < lim; ++k) |
| 65 | dst[k] = ~src[k]; |
| 66 | |
| 67 | if (bits % BITS_PER_LONG) |
Rasmus Villemoes | 65b4ee6 | 2014-08-06 16:09:57 -0700 | [diff] [blame] | 68 | dst[k] = ~src[k]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | } |
| 70 | EXPORT_SYMBOL(__bitmap_complement); |
| 71 | |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 72 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | * __bitmap_shift_right - logical right shift of the bits in a bitmap |
Randy Dunlap | 05fb6bf | 2007-02-28 20:12:13 -0800 | [diff] [blame] | 74 | * @dst : destination bitmap |
| 75 | * @src : source bitmap |
| 76 | * @shift : shift by this many bits |
Rasmus Villemoes | 2fbad29 | 2015-02-13 14:36:02 -0800 | [diff] [blame] | 77 | * @nbits : bitmap size, in bits |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | * |
| 79 | * Shifting right (dividing) means moving bits in the MS -> LS bit |
| 80 | * direction. Zeros are fed into the vacated MS positions and the |
| 81 | * LS bits shifted off the bottom are lost. |
| 82 | */ |
Rasmus Villemoes | 2fbad29 | 2015-02-13 14:36:02 -0800 | [diff] [blame] | 83 | void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
| 84 | unsigned shift, unsigned nbits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | { |
Rasmus Villemoes | cfac1d0 | 2015-02-13 14:36:10 -0800 | [diff] [blame] | 86 | unsigned k, lim = BITS_TO_LONGS(nbits); |
Rasmus Villemoes | 2fbad29 | 2015-02-13 14:36:02 -0800 | [diff] [blame] | 87 | unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
Rasmus Villemoes | cfac1d0 | 2015-02-13 14:36:10 -0800 | [diff] [blame] | 88 | unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | for (k = 0; off + k < lim; ++k) { |
| 90 | unsigned long upper, lower; |
| 91 | |
| 92 | /* |
| 93 | * If shift is not word aligned, take lower rem bits of |
| 94 | * word above and make them the top rem bits of result. |
| 95 | */ |
| 96 | if (!rem || off + k + 1 >= lim) |
| 97 | upper = 0; |
| 98 | else { |
| 99 | upper = src[off + k + 1]; |
Rasmus Villemoes | cfac1d0 | 2015-02-13 14:36:10 -0800 | [diff] [blame] | 100 | if (off + k + 1 == lim - 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | upper &= mask; |
Rasmus Villemoes | 9d8a6b2 | 2015-02-13 14:36:05 -0800 | [diff] [blame] | 102 | upper <<= (BITS_PER_LONG - rem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | } |
| 104 | lower = src[off + k]; |
Rasmus Villemoes | cfac1d0 | 2015-02-13 14:36:10 -0800 | [diff] [blame] | 105 | if (off + k == lim - 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | lower &= mask; |
Rasmus Villemoes | 9d8a6b2 | 2015-02-13 14:36:05 -0800 | [diff] [blame] | 107 | lower >>= rem; |
| 108 | dst[k] = lower | upper; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | } |
| 110 | if (off) |
| 111 | memset(&dst[lim - off], 0, off*sizeof(unsigned long)); |
| 112 | } |
| 113 | EXPORT_SYMBOL(__bitmap_shift_right); |
| 114 | |
| 115 | |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 116 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | * __bitmap_shift_left - logical left shift of the bits in a bitmap |
Randy Dunlap | 05fb6bf | 2007-02-28 20:12:13 -0800 | [diff] [blame] | 118 | * @dst : destination bitmap |
| 119 | * @src : source bitmap |
| 120 | * @shift : shift by this many bits |
Rasmus Villemoes | dba94c2 | 2015-02-13 14:36:13 -0800 | [diff] [blame] | 121 | * @nbits : bitmap size, in bits |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | * |
| 123 | * Shifting left (multiplying) means moving bits in the LS -> MS |
| 124 | * direction. Zeros are fed into the vacated LS bit positions |
| 125 | * and those MS bits shifted off the top are lost. |
| 126 | */ |
| 127 | |
Rasmus Villemoes | dba94c2 | 2015-02-13 14:36:13 -0800 | [diff] [blame] | 128 | void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
| 129 | unsigned int shift, unsigned int nbits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | { |
Rasmus Villemoes | dba94c2 | 2015-02-13 14:36:13 -0800 | [diff] [blame] | 131 | int k; |
Rasmus Villemoes | 7f59065 | 2015-02-13 14:36:19 -0800 | [diff] [blame] | 132 | unsigned int lim = BITS_TO_LONGS(nbits); |
Rasmus Villemoes | dba94c2 | 2015-02-13 14:36:13 -0800 | [diff] [blame] | 133 | unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | for (k = lim - off - 1; k >= 0; --k) { |
| 135 | unsigned long upper, lower; |
| 136 | |
| 137 | /* |
| 138 | * If shift is not word aligned, take upper rem bits of |
| 139 | * word below and make them the bottom rem bits of result. |
| 140 | */ |
| 141 | if (rem && k > 0) |
Rasmus Villemoes | 6d874ec | 2015-02-13 14:36:16 -0800 | [diff] [blame] | 142 | lower = src[k - 1] >> (BITS_PER_LONG - rem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | else |
| 144 | lower = 0; |
Rasmus Villemoes | 7f59065 | 2015-02-13 14:36:19 -0800 | [diff] [blame] | 145 | upper = src[k] << rem; |
Rasmus Villemoes | 6d874ec | 2015-02-13 14:36:16 -0800 | [diff] [blame] | 146 | dst[k + off] = lower | upper; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | } |
| 148 | if (off) |
| 149 | memset(dst, 0, off*sizeof(unsigned long)); |
| 150 | } |
| 151 | EXPORT_SYMBOL(__bitmap_shift_left); |
| 152 | |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 153 | int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 154 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | { |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 156 | unsigned int k; |
Rasmus Villemoes | 7e5f97d | 2014-08-06 16:10:22 -0700 | [diff] [blame] | 157 | unsigned int lim = bits/BITS_PER_LONG; |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 158 | unsigned long result = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | |
Rasmus Villemoes | 7e5f97d | 2014-08-06 16:10:22 -0700 | [diff] [blame] | 160 | for (k = 0; k < lim; k++) |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 161 | result |= (dst[k] = bitmap1[k] & bitmap2[k]); |
Rasmus Villemoes | 7e5f97d | 2014-08-06 16:10:22 -0700 | [diff] [blame] | 162 | if (bits % BITS_PER_LONG) |
| 163 | result |= (dst[k] = bitmap1[k] & bitmap2[k] & |
| 164 | BITMAP_LAST_WORD_MASK(bits)); |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 165 | return result != 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | } |
| 167 | EXPORT_SYMBOL(__bitmap_and); |
| 168 | |
| 169 | void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 170 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | { |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 172 | unsigned int k; |
| 173 | unsigned int nr = BITS_TO_LONGS(bits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | |
| 175 | for (k = 0; k < nr; k++) |
| 176 | dst[k] = bitmap1[k] | bitmap2[k]; |
| 177 | } |
| 178 | EXPORT_SYMBOL(__bitmap_or); |
| 179 | |
| 180 | void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 181 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | { |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 183 | unsigned int k; |
| 184 | unsigned int nr = BITS_TO_LONGS(bits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | |
| 186 | for (k = 0; k < nr; k++) |
| 187 | dst[k] = bitmap1[k] ^ bitmap2[k]; |
| 188 | } |
| 189 | EXPORT_SYMBOL(__bitmap_xor); |
| 190 | |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 191 | int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 192 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | { |
Rasmus Villemoes | 2f9305e | 2014-08-06 16:09:59 -0700 | [diff] [blame] | 194 | unsigned int k; |
Rasmus Villemoes | 74e7653 | 2014-08-06 16:10:24 -0700 | [diff] [blame] | 195 | unsigned int lim = bits/BITS_PER_LONG; |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 196 | unsigned long result = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | |
Rasmus Villemoes | 74e7653 | 2014-08-06 16:10:24 -0700 | [diff] [blame] | 198 | for (k = 0; k < lim; k++) |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 199 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k]); |
Rasmus Villemoes | 74e7653 | 2014-08-06 16:10:24 -0700 | [diff] [blame] | 200 | if (bits % BITS_PER_LONG) |
| 201 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k] & |
| 202 | BITMAP_LAST_WORD_MASK(bits)); |
Linus Torvalds | f4b0373 | 2009-08-21 09:26:15 -0700 | [diff] [blame] | 203 | return result != 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 204 | } |
| 205 | EXPORT_SYMBOL(__bitmap_andnot); |
| 206 | |
| 207 | int __bitmap_intersects(const unsigned long *bitmap1, |
Rasmus Villemoes | 6dfe979 | 2014-08-06 16:10:01 -0700 | [diff] [blame] | 208 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | { |
Rasmus Villemoes | 6dfe979 | 2014-08-06 16:10:01 -0700 | [diff] [blame] | 210 | unsigned int k, lim = bits/BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | for (k = 0; k < lim; ++k) |
| 212 | if (bitmap1[k] & bitmap2[k]) |
| 213 | return 1; |
| 214 | |
| 215 | if (bits % BITS_PER_LONG) |
| 216 | if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) |
| 217 | return 1; |
| 218 | return 0; |
| 219 | } |
| 220 | EXPORT_SYMBOL(__bitmap_intersects); |
| 221 | |
| 222 | int __bitmap_subset(const unsigned long *bitmap1, |
Rasmus Villemoes | 5be2021 | 2014-08-06 16:10:03 -0700 | [diff] [blame] | 223 | const unsigned long *bitmap2, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | { |
Rasmus Villemoes | 5be2021 | 2014-08-06 16:10:03 -0700 | [diff] [blame] | 225 | unsigned int k, lim = bits/BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | for (k = 0; k < lim; ++k) |
| 227 | if (bitmap1[k] & ~bitmap2[k]) |
| 228 | return 0; |
| 229 | |
| 230 | if (bits % BITS_PER_LONG) |
| 231 | if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) |
| 232 | return 0; |
| 233 | return 1; |
| 234 | } |
| 235 | EXPORT_SYMBOL(__bitmap_subset); |
| 236 | |
Rasmus Villemoes | 877d9f3 | 2014-08-06 16:10:05 -0700 | [diff] [blame] | 237 | int __bitmap_weight(const unsigned long *bitmap, unsigned int bits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | { |
Rasmus Villemoes | 877d9f3 | 2014-08-06 16:10:05 -0700 | [diff] [blame] | 239 | unsigned int k, lim = bits/BITS_PER_LONG; |
| 240 | int w = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | |
| 242 | for (k = 0; k < lim; k++) |
Akinobu Mita | 37d5411 | 2006-03-26 01:39:56 -0800 | [diff] [blame] | 243 | w += hweight_long(bitmap[k]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | |
| 245 | if (bits % BITS_PER_LONG) |
Akinobu Mita | 37d5411 | 2006-03-26 01:39:56 -0800 | [diff] [blame] | 246 | w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | |
| 248 | return w; |
| 249 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | EXPORT_SYMBOL(__bitmap_weight); |
| 251 | |
Rasmus Villemoes | fb5ac54 | 2014-08-06 16:10:07 -0700 | [diff] [blame] | 252 | void bitmap_set(unsigned long *map, unsigned int start, int len) |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 253 | { |
| 254 | unsigned long *p = map + BIT_WORD(start); |
Rasmus Villemoes | fb5ac54 | 2014-08-06 16:10:07 -0700 | [diff] [blame] | 255 | const unsigned int size = start + len; |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 256 | int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); |
| 257 | unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); |
| 258 | |
Rasmus Villemoes | fb5ac54 | 2014-08-06 16:10:07 -0700 | [diff] [blame] | 259 | while (len - bits_to_set >= 0) { |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 260 | *p |= mask_to_set; |
Rasmus Villemoes | fb5ac54 | 2014-08-06 16:10:07 -0700 | [diff] [blame] | 261 | len -= bits_to_set; |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 262 | bits_to_set = BITS_PER_LONG; |
| 263 | mask_to_set = ~0UL; |
| 264 | p++; |
| 265 | } |
Rasmus Villemoes | fb5ac54 | 2014-08-06 16:10:07 -0700 | [diff] [blame] | 266 | if (len) { |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 267 | mask_to_set &= BITMAP_LAST_WORD_MASK(size); |
| 268 | *p |= mask_to_set; |
| 269 | } |
| 270 | } |
| 271 | EXPORT_SYMBOL(bitmap_set); |
| 272 | |
Rasmus Villemoes | 154f5e3 | 2014-08-06 16:10:10 -0700 | [diff] [blame] | 273 | void bitmap_clear(unsigned long *map, unsigned int start, int len) |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 274 | { |
| 275 | unsigned long *p = map + BIT_WORD(start); |
Rasmus Villemoes | 154f5e3 | 2014-08-06 16:10:10 -0700 | [diff] [blame] | 276 | const unsigned int size = start + len; |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 277 | int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); |
| 278 | unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); |
| 279 | |
Rasmus Villemoes | 154f5e3 | 2014-08-06 16:10:10 -0700 | [diff] [blame] | 280 | while (len - bits_to_clear >= 0) { |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 281 | *p &= ~mask_to_clear; |
Rasmus Villemoes | 154f5e3 | 2014-08-06 16:10:10 -0700 | [diff] [blame] | 282 | len -= bits_to_clear; |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 283 | bits_to_clear = BITS_PER_LONG; |
| 284 | mask_to_clear = ~0UL; |
| 285 | p++; |
| 286 | } |
Rasmus Villemoes | 154f5e3 | 2014-08-06 16:10:10 -0700 | [diff] [blame] | 287 | if (len) { |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 288 | mask_to_clear &= BITMAP_LAST_WORD_MASK(size); |
| 289 | *p &= ~mask_to_clear; |
| 290 | } |
| 291 | } |
| 292 | EXPORT_SYMBOL(bitmap_clear); |
| 293 | |
Michal Nazarewicz | 5e19b01 | 2014-12-12 16:54:45 -0800 | [diff] [blame] | 294 | /** |
| 295 | * bitmap_find_next_zero_area_off - find a contiguous aligned zero area |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 296 | * @map: The address to base the search on |
| 297 | * @size: The bitmap size in bits |
| 298 | * @start: The bitnumber to start searching at |
| 299 | * @nr: The number of zeroed bits we're looking for |
| 300 | * @align_mask: Alignment mask for zero area |
Michal Nazarewicz | 5e19b01 | 2014-12-12 16:54:45 -0800 | [diff] [blame] | 301 | * @align_offset: Alignment offset for zero area. |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 302 | * |
| 303 | * The @align_mask should be one less than a power of 2; the effect is that |
Michal Nazarewicz | 5e19b01 | 2014-12-12 16:54:45 -0800 | [diff] [blame] | 304 | * the bit offset of all zero areas this function finds plus @align_offset |
| 305 | * is multiple of that power of 2. |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 306 | */ |
Michal Nazarewicz | 5e19b01 | 2014-12-12 16:54:45 -0800 | [diff] [blame] | 307 | unsigned long bitmap_find_next_zero_area_off(unsigned long *map, |
| 308 | unsigned long size, |
| 309 | unsigned long start, |
| 310 | unsigned int nr, |
| 311 | unsigned long align_mask, |
| 312 | unsigned long align_offset) |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 313 | { |
| 314 | unsigned long index, end, i; |
| 315 | again: |
| 316 | index = find_next_zero_bit(map, size, start); |
| 317 | |
| 318 | /* Align allocation */ |
Michal Nazarewicz | 5e19b01 | 2014-12-12 16:54:45 -0800 | [diff] [blame] | 319 | index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset; |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 320 | |
| 321 | end = index + nr; |
| 322 | if (end > size) |
| 323 | return end; |
| 324 | i = find_next_bit(map, end, index); |
| 325 | if (i < end) { |
| 326 | start = i + 1; |
| 327 | goto again; |
| 328 | } |
| 329 | return index; |
| 330 | } |
Michal Nazarewicz | 5e19b01 | 2014-12-12 16:54:45 -0800 | [diff] [blame] | 331 | EXPORT_SYMBOL(bitmap_find_next_zero_area_off); |
Akinobu Mita | c1a2a96 | 2009-12-15 16:48:25 -0800 | [diff] [blame] | 332 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | /* |
Nadia Yvette Chambers | 6d49e35 | 2012-12-06 10:39:54 +0100 | [diff] [blame] | 334 | * Bitmap printing & parsing functions: first version by Nadia Yvette Chambers, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | * second version by Paul Jackson, third by Joe Korty. |
| 336 | */ |
| 337 | |
| 338 | #define CHUNKSZ 32 |
| 339 | #define nbits_to_hold_value(val) fls(val) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | #define BASEDEC 10 /* fancier cpuset lists input in decimal */ |
| 341 | |
| 342 | /** |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 343 | * __bitmap_parse - convert an ASCII hex string into a bitmap. |
| 344 | * @buf: pointer to buffer containing string. |
| 345 | * @buflen: buffer size in bytes. If string is smaller than this |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | * then it must be terminated with a \0. |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 347 | * @is_user: location of buffer, 0 indicates kernel space |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | * @maskp: pointer to bitmap array that will contain result. |
| 349 | * @nmaskbits: size of bitmap, in bits. |
| 350 | * |
| 351 | * Commas group hex digits into chunks. Each chunk defines exactly 32 |
| 352 | * bits of the resultant bitmask. No chunk may specify a value larger |
Randy Dunlap | 6e1907ff | 2006-06-25 05:48:57 -0700 | [diff] [blame] | 353 | * than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value |
| 354 | * then leading 0-bits are prepended. %-EINVAL is returned for illegal |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | * characters and for grouping errors such as "1,,5", ",44", "," and "". |
| 356 | * Leading and trailing whitespace accepted, but not embedded whitespace. |
| 357 | */ |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 358 | int __bitmap_parse(const char *buf, unsigned int buflen, |
| 359 | int is_user, unsigned long *maskp, |
| 360 | int nmaskbits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | { |
| 362 | int c, old_c, totaldigits, ndigits, nchunks, nbits; |
| 363 | u32 chunk; |
H Hartley Sweeten | b9c321f | 2011-10-31 17:12:32 -0700 | [diff] [blame] | 364 | const char __user __force *ubuf = (const char __user __force *)buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | |
| 366 | bitmap_zero(maskp, nmaskbits); |
| 367 | |
| 368 | nchunks = nbits = totaldigits = c = 0; |
| 369 | do { |
| 370 | chunk = ndigits = 0; |
| 371 | |
| 372 | /* Get the next chunk of the bitmap */ |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 373 | while (buflen) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | old_c = c; |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 375 | if (is_user) { |
| 376 | if (__get_user(c, ubuf++)) |
| 377 | return -EFAULT; |
| 378 | } |
| 379 | else |
| 380 | c = *buf++; |
| 381 | buflen--; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | if (isspace(c)) |
| 383 | continue; |
| 384 | |
| 385 | /* |
| 386 | * If the last character was a space and the current |
| 387 | * character isn't '\0', we've got embedded whitespace. |
| 388 | * This is a no-no, so throw an error. |
| 389 | */ |
| 390 | if (totaldigits && c && isspace(old_c)) |
| 391 | return -EINVAL; |
| 392 | |
| 393 | /* A '\0' or a ',' signal the end of the chunk */ |
| 394 | if (c == '\0' || c == ',') |
| 395 | break; |
| 396 | |
| 397 | if (!isxdigit(c)) |
| 398 | return -EINVAL; |
| 399 | |
| 400 | /* |
| 401 | * Make sure there are at least 4 free bits in 'chunk'. |
| 402 | * If not, this hexdigit will overflow 'chunk', so |
| 403 | * throw an error. |
| 404 | */ |
| 405 | if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1)) |
| 406 | return -EOVERFLOW; |
| 407 | |
Andy Shevchenko | 66f1991 | 2010-10-26 14:23:03 -0700 | [diff] [blame] | 408 | chunk = (chunk << 4) | hex_to_bin(c); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | ndigits++; totaldigits++; |
| 410 | } |
| 411 | if (ndigits == 0) |
| 412 | return -EINVAL; |
| 413 | if (nchunks == 0 && chunk == 0) |
| 414 | continue; |
| 415 | |
| 416 | __bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits); |
| 417 | *maskp |= chunk; |
| 418 | nchunks++; |
| 419 | nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ; |
| 420 | if (nbits > nmaskbits) |
| 421 | return -EOVERFLOW; |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 422 | } while (buflen && c == ','); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | |
| 424 | return 0; |
| 425 | } |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 426 | EXPORT_SYMBOL(__bitmap_parse); |
| 427 | |
| 428 | /** |
Ben Hutchings | 9a86e2b | 2010-03-05 13:43:17 -0800 | [diff] [blame] | 429 | * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 430 | * |
| 431 | * @ubuf: pointer to user buffer containing string. |
| 432 | * @ulen: buffer size in bytes. If string is smaller than this |
| 433 | * then it must be terminated with a \0. |
| 434 | * @maskp: pointer to bitmap array that will contain result. |
| 435 | * @nmaskbits: size of bitmap, in bits. |
| 436 | * |
| 437 | * Wrapper for __bitmap_parse(), providing it with user buffer. |
| 438 | * |
| 439 | * We cannot have this as an inline function in bitmap.h because it needs |
| 440 | * linux/uaccess.h to get the access_ok() declaration and this causes |
| 441 | * cyclic dependencies. |
| 442 | */ |
| 443 | int bitmap_parse_user(const char __user *ubuf, |
| 444 | unsigned int ulen, unsigned long *maskp, |
| 445 | int nmaskbits) |
| 446 | { |
| 447 | if (!access_ok(VERIFY_READ, ubuf, ulen)) |
| 448 | return -EFAULT; |
H Hartley Sweeten | b9c321f | 2011-10-31 17:12:32 -0700 | [diff] [blame] | 449 | return __bitmap_parse((const char __force *)ubuf, |
| 450 | ulen, 1, maskp, nmaskbits); |
| 451 | |
Reinette Chatre | 01a3ee2 | 2006-10-11 01:21:55 -0700 | [diff] [blame] | 452 | } |
| 453 | EXPORT_SYMBOL(bitmap_parse_user); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | /** |
Sudeep Holla | 5aaba36 | 2014-09-30 14:48:22 +0100 | [diff] [blame] | 456 | * bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string |
| 457 | * @list: indicates whether the bitmap must be list |
| 458 | * @buf: page aligned buffer into which string is placed |
| 459 | * @maskp: pointer to bitmap to convert |
| 460 | * @nmaskbits: size of bitmap, in bits |
| 461 | * |
| 462 | * Output format is a comma-separated list of decimal numbers and |
| 463 | * ranges if list is specified or hex digits grouped into comma-separated |
| 464 | * sets of 8 digits/set. Returns the number of characters written to buf. |
Sudeep Holla | 9cf79d1 | 2015-06-25 15:02:17 -0700 | [diff] [blame] | 465 | * |
| 466 | * It is assumed that @buf is a pointer into a PAGE_SIZE area and that |
| 467 | * sufficient storage remains at @buf to accommodate the |
| 468 | * bitmap_print_to_pagebuf() output. |
Sudeep Holla | 5aaba36 | 2014-09-30 14:48:22 +0100 | [diff] [blame] | 469 | */ |
| 470 | int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, |
| 471 | int nmaskbits) |
| 472 | { |
Sudeep Holla | 9cf79d1 | 2015-06-25 15:02:17 -0700 | [diff] [blame] | 473 | ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf; |
Sudeep Holla | 5aaba36 | 2014-09-30 14:48:22 +0100 | [diff] [blame] | 474 | int n = 0; |
| 475 | |
Sudeep Holla | 9cf79d1 | 2015-06-25 15:02:17 -0700 | [diff] [blame] | 476 | if (len > 1) |
| 477 | n = list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) : |
| 478 | scnprintf(buf, len, "%*pb\n", nmaskbits, maskp); |
Sudeep Holla | 5aaba36 | 2014-09-30 14:48:22 +0100 | [diff] [blame] | 479 | return n; |
| 480 | } |
| 481 | EXPORT_SYMBOL(bitmap_print_to_pagebuf); |
| 482 | |
| 483 | /** |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 484 | * __bitmap_parselist - convert list format ASCII string to bitmap |
Randy Dunlap | b0825ee | 2011-06-15 15:08:10 -0700 | [diff] [blame] | 485 | * @buf: read nul-terminated user string from this buffer |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 486 | * @buflen: buffer size in bytes. If string is smaller than this |
| 487 | * then it must be terminated with a \0. |
| 488 | * @is_user: location of buffer, 0 indicates kernel space |
Randy Dunlap | 6e1907ff | 2006-06-25 05:48:57 -0700 | [diff] [blame] | 489 | * @maskp: write resulting mask here |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 490 | * @nmaskbits: number of bits in mask to be written |
| 491 | * |
| 492 | * Input format is a comma-separated list of decimal numbers and |
| 493 | * ranges. Consecutively set bits are shown as two hyphen-separated |
| 494 | * decimal numbers, the smallest and largest bit numbers set in |
| 495 | * the range. |
| 496 | * |
Randy Dunlap | 6e1907ff | 2006-06-25 05:48:57 -0700 | [diff] [blame] | 497 | * Returns 0 on success, -errno on invalid input strings. |
| 498 | * Error values: |
| 499 | * %-EINVAL: second number in range smaller than first |
| 500 | * %-EINVAL: invalid character in string |
| 501 | * %-ERANGE: bit number specified too large for mask |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | */ |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 503 | static int __bitmap_parselist(const char *buf, unsigned int buflen, |
| 504 | int is_user, unsigned long *maskp, |
| 505 | int nmaskbits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | { |
| 507 | unsigned a, b; |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 508 | int c, old_c, totaldigits; |
H Hartley Sweeten | b9c321f | 2011-10-31 17:12:32 -0700 | [diff] [blame] | 509 | const char __user __force *ubuf = (const char __user __force *)buf; |
Chris Metcalf | 2528a8b | 2015-06-25 15:02:08 -0700 | [diff] [blame] | 510 | int at_start, in_range; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 512 | totaldigits = c = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | bitmap_zero(maskp, nmaskbits); |
| 514 | do { |
Chris Metcalf | 2528a8b | 2015-06-25 15:02:08 -0700 | [diff] [blame] | 515 | at_start = 1; |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 516 | in_range = 0; |
| 517 | a = b = 0; |
| 518 | |
| 519 | /* Get the next cpu# or a range of cpu#'s */ |
| 520 | while (buflen) { |
| 521 | old_c = c; |
| 522 | if (is_user) { |
| 523 | if (__get_user(c, ubuf++)) |
| 524 | return -EFAULT; |
| 525 | } else |
| 526 | c = *buf++; |
| 527 | buflen--; |
| 528 | if (isspace(c)) |
| 529 | continue; |
| 530 | |
| 531 | /* |
| 532 | * If the last character was a space and the current |
| 533 | * character isn't '\0', we've got embedded whitespace. |
| 534 | * This is a no-no, so throw an error. |
| 535 | */ |
| 536 | if (totaldigits && c && isspace(old_c)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | return -EINVAL; |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 538 | |
| 539 | /* A '\0' or a ',' signal the end of a cpu# or range */ |
| 540 | if (c == '\0' || c == ',') |
| 541 | break; |
| 542 | |
| 543 | if (c == '-') { |
Chris Metcalf | 2528a8b | 2015-06-25 15:02:08 -0700 | [diff] [blame] | 544 | if (at_start || in_range) |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 545 | return -EINVAL; |
| 546 | b = 0; |
| 547 | in_range = 1; |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 548 | continue; |
| 549 | } |
| 550 | |
| 551 | if (!isdigit(c)) |
| 552 | return -EINVAL; |
| 553 | |
| 554 | b = b * 10 + (c - '0'); |
| 555 | if (!in_range) |
| 556 | a = b; |
Chris Metcalf | 2528a8b | 2015-06-25 15:02:08 -0700 | [diff] [blame] | 557 | at_start = 0; |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 558 | totaldigits++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | } |
| 560 | if (!(a <= b)) |
| 561 | return -EINVAL; |
| 562 | if (b >= nmaskbits) |
| 563 | return -ERANGE; |
Chris Metcalf | 2528a8b | 2015-06-25 15:02:08 -0700 | [diff] [blame] | 564 | if (!at_start) { |
| 565 | while (a <= b) { |
| 566 | set_bit(a, maskp); |
| 567 | a++; |
| 568 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 569 | } |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 570 | } while (buflen && c == ','); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | return 0; |
| 572 | } |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 573 | |
| 574 | int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits) |
| 575 | { |
Rasmus Villemoes | bc5be18 | 2014-08-06 16:10:12 -0700 | [diff] [blame] | 576 | char *nl = strchrnul(bp, '\n'); |
| 577 | int len = nl - bp; |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 578 | |
| 579 | return __bitmap_parselist(bp, len, 0, maskp, nmaskbits); |
| 580 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | EXPORT_SYMBOL(bitmap_parselist); |
| 582 | |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 583 | |
| 584 | /** |
| 585 | * bitmap_parselist_user() |
| 586 | * |
| 587 | * @ubuf: pointer to user buffer containing string. |
| 588 | * @ulen: buffer size in bytes. If string is smaller than this |
| 589 | * then it must be terminated with a \0. |
| 590 | * @maskp: pointer to bitmap array that will contain result. |
| 591 | * @nmaskbits: size of bitmap, in bits. |
| 592 | * |
| 593 | * Wrapper for bitmap_parselist(), providing it with user buffer. |
| 594 | * |
| 595 | * We cannot have this as an inline function in bitmap.h because it needs |
| 596 | * linux/uaccess.h to get the access_ok() declaration and this causes |
| 597 | * cyclic dependencies. |
| 598 | */ |
| 599 | int bitmap_parselist_user(const char __user *ubuf, |
| 600 | unsigned int ulen, unsigned long *maskp, |
| 601 | int nmaskbits) |
| 602 | { |
| 603 | if (!access_ok(VERIFY_READ, ubuf, ulen)) |
| 604 | return -EFAULT; |
H Hartley Sweeten | b9c321f | 2011-10-31 17:12:32 -0700 | [diff] [blame] | 605 | return __bitmap_parselist((const char __force *)ubuf, |
Mike Travis | 4b06042 | 2011-05-24 17:13:12 -0700 | [diff] [blame] | 606 | ulen, 1, maskp, nmaskbits); |
| 607 | } |
| 608 | EXPORT_SYMBOL(bitmap_parselist_user); |
| 609 | |
| 610 | |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 611 | /** |
Ben Hutchings | 9a86e2b | 2010-03-05 13:43:17 -0800 | [diff] [blame] | 612 | * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 613 | * @buf: pointer to a bitmap |
Rasmus Villemoes | df1d80a | 2015-02-12 15:02:07 -0800 | [diff] [blame] | 614 | * @pos: a bit position in @buf (0 <= @pos < @nbits) |
| 615 | * @nbits: number of valid bit positions in @buf |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 616 | * |
Rasmus Villemoes | df1d80a | 2015-02-12 15:02:07 -0800 | [diff] [blame] | 617 | * Map the bit at position @pos in @buf (of length @nbits) to the |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 618 | * ordinal of which set bit it is. If it is not set or if @pos |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 619 | * is not a valid bit position, map to -1. |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 620 | * |
| 621 | * If for example, just bits 4 through 7 are set in @buf, then @pos |
| 622 | * values 4 through 7 will get mapped to 0 through 3, respectively, |
Rasmus Villemoes | a855174 | 2014-08-06 16:10:14 -0700 | [diff] [blame] | 623 | * and other @pos values will get mapped to -1. When @pos value 7 |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 624 | * gets mapped to (returns) @ord value 3 in this example, that means |
| 625 | * that bit 7 is the 3rd (starting with 0th) set bit in @buf. |
| 626 | * |
| 627 | * The bit positions 0 through @bits are valid positions in @buf. |
| 628 | */ |
Rasmus Villemoes | df1d80a | 2015-02-12 15:02:07 -0800 | [diff] [blame] | 629 | static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits) |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 630 | { |
Rasmus Villemoes | df1d80a | 2015-02-12 15:02:07 -0800 | [diff] [blame] | 631 | if (pos >= nbits || !test_bit(pos, buf)) |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 632 | return -1; |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 633 | |
Rasmus Villemoes | df1d80a | 2015-02-12 15:02:07 -0800 | [diff] [blame] | 634 | return __bitmap_weight(buf, pos); |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 635 | } |
| 636 | |
| 637 | /** |
Ben Hutchings | 9a86e2b | 2010-03-05 13:43:17 -0800 | [diff] [blame] | 638 | * bitmap_ord_to_pos - find position of n-th set bit in bitmap |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 639 | * @buf: pointer to bitmap |
| 640 | * @ord: ordinal bit position (n-th set bit, n >= 0) |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 641 | * @nbits: number of valid bit positions in @buf |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 642 | * |
| 643 | * Map the ordinal offset of bit @ord in @buf to its position in @buf. |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 644 | * Value of @ord should be in range 0 <= @ord < weight(buf). If @ord |
| 645 | * >= weight(buf), returns @nbits. |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 646 | * |
| 647 | * If for example, just bits 4 through 7 are set in @buf, then @ord |
| 648 | * values 0 through 3 will get mapped to 4 through 7, respectively, |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 649 | * and all other @ord values returns @nbits. When @ord value 3 |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 650 | * gets mapped to (returns) @pos value 7 in this example, that means |
| 651 | * that the 3rd set bit (starting with 0th) is at position 7 in @buf. |
| 652 | * |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 653 | * The bit positions 0 through @nbits-1 are valid positions in @buf. |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 654 | */ |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 655 | unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits) |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 656 | { |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 657 | unsigned int pos; |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 658 | |
Rasmus Villemoes | f6a1f5d | 2015-02-12 15:02:10 -0800 | [diff] [blame] | 659 | for (pos = find_first_bit(buf, nbits); |
| 660 | pos < nbits && ord; |
| 661 | pos = find_next_bit(buf, nbits, pos + 1)) |
| 662 | ord--; |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 663 | |
| 664 | return pos; |
| 665 | } |
| 666 | |
| 667 | /** |
| 668 | * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 669 | * @dst: remapped result |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 670 | * @src: subset to be remapped |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 671 | * @old: defines domain of map |
| 672 | * @new: defines range of map |
Rasmus Villemoes | 9814ec1 | 2015-02-12 15:02:13 -0800 | [diff] [blame] | 673 | * @nbits: number of bits in each of these bitmaps |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 674 | * |
| 675 | * Let @old and @new define a mapping of bit positions, such that |
| 676 | * whatever position is held by the n-th set bit in @old is mapped |
| 677 | * to the n-th set bit in @new. In the more general case, allowing |
| 678 | * for the possibility that the weight 'w' of @new is less than the |
| 679 | * weight of @old, map the position of the n-th set bit in @old to |
| 680 | * the position of the m-th set bit in @new, where m == n % w. |
| 681 | * |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 682 | * If either of the @old and @new bitmaps are empty, or if @src and |
| 683 | * @dst point to the same location, then this routine copies @src |
| 684 | * to @dst. |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 685 | * |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 686 | * The positions of unset bits in @old are mapped to themselves |
| 687 | * (the identify map). |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 688 | * |
| 689 | * Apply the above specified mapping to @src, placing the result in |
| 690 | * @dst, clearing any bits previously set in @dst. |
| 691 | * |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 692 | * For example, lets say that @old has bits 4 through 7 set, and |
| 693 | * @new has bits 12 through 15 set. This defines the mapping of bit |
| 694 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 695 | * bit positions unchanged. So if say @src comes into this routine |
| 696 | * with bits 1, 5 and 7 set, then @dst should leave with bits 1, |
| 697 | * 13 and 15 set. |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 698 | */ |
| 699 | void bitmap_remap(unsigned long *dst, const unsigned long *src, |
| 700 | const unsigned long *old, const unsigned long *new, |
Rasmus Villemoes | 9814ec1 | 2015-02-12 15:02:13 -0800 | [diff] [blame] | 701 | unsigned int nbits) |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 702 | { |
Rasmus Villemoes | 9814ec1 | 2015-02-12 15:02:13 -0800 | [diff] [blame] | 703 | unsigned int oldbit, w; |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 704 | |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 705 | if (dst == src) /* following doesn't handle inplace remaps */ |
| 706 | return; |
Rasmus Villemoes | 9814ec1 | 2015-02-12 15:02:13 -0800 | [diff] [blame] | 707 | bitmap_zero(dst, nbits); |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 708 | |
Rasmus Villemoes | 9814ec1 | 2015-02-12 15:02:13 -0800 | [diff] [blame] | 709 | w = bitmap_weight(new, nbits); |
| 710 | for_each_set_bit(oldbit, src, nbits) { |
| 711 | int n = bitmap_pos_to_ord(old, oldbit, nbits); |
Akinobu Mita | 08564fb | 2010-03-05 13:43:18 -0800 | [diff] [blame] | 712 | |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 713 | if (n < 0 || w == 0) |
| 714 | set_bit(oldbit, dst); /* identity map */ |
| 715 | else |
Rasmus Villemoes | 9814ec1 | 2015-02-12 15:02:13 -0800 | [diff] [blame] | 716 | set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst); |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 717 | } |
| 718 | } |
| 719 | EXPORT_SYMBOL(bitmap_remap); |
| 720 | |
| 721 | /** |
| 722 | * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit |
Randy Dunlap | 6e1907ff | 2006-06-25 05:48:57 -0700 | [diff] [blame] | 723 | * @oldbit: bit position to be mapped |
| 724 | * @old: defines domain of map |
| 725 | * @new: defines range of map |
| 726 | * @bits: number of bits in each of these bitmaps |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 727 | * |
| 728 | * Let @old and @new define a mapping of bit positions, such that |
| 729 | * whatever position is held by the n-th set bit in @old is mapped |
| 730 | * to the n-th set bit in @new. In the more general case, allowing |
| 731 | * for the possibility that the weight 'w' of @new is less than the |
| 732 | * weight of @old, map the position of the n-th set bit in @old to |
| 733 | * the position of the m-th set bit in @new, where m == n % w. |
| 734 | * |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 735 | * The positions of unset bits in @old are mapped to themselves |
| 736 | * (the identify map). |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 737 | * |
| 738 | * Apply the above specified mapping to bit position @oldbit, returning |
| 739 | * the new bit position. |
| 740 | * |
| 741 | * For example, lets say that @old has bits 4 through 7 set, and |
| 742 | * @new has bits 12 through 15 set. This defines the mapping of bit |
| 743 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 744 | * bit positions unchanged. So if say @oldbit is 5, then this routine |
| 745 | * returns 13. |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 746 | */ |
| 747 | int bitmap_bitremap(int oldbit, const unsigned long *old, |
| 748 | const unsigned long *new, int bits) |
| 749 | { |
Paul Jackson | 96b7f34 | 2006-01-08 01:01:46 -0800 | [diff] [blame] | 750 | int w = bitmap_weight(new, bits); |
| 751 | int n = bitmap_pos_to_ord(old, oldbit, bits); |
| 752 | if (n < 0 || w == 0) |
| 753 | return oldbit; |
| 754 | else |
| 755 | return bitmap_ord_to_pos(new, n % w, bits); |
Paul Jackson | fb5eeee | 2005-10-30 15:02:33 -0800 | [diff] [blame] | 756 | } |
| 757 | EXPORT_SYMBOL(bitmap_bitremap); |
| 758 | |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 759 | /** |
| 760 | * bitmap_onto - translate one bitmap relative to another |
| 761 | * @dst: resulting translated bitmap |
| 762 | * @orig: original untranslated bitmap |
| 763 | * @relmap: bitmap relative to which translated |
| 764 | * @bits: number of bits in each of these bitmaps |
| 765 | * |
| 766 | * Set the n-th bit of @dst iff there exists some m such that the |
| 767 | * n-th bit of @relmap is set, the m-th bit of @orig is set, and |
| 768 | * the n-th bit of @relmap is also the m-th _set_ bit of @relmap. |
| 769 | * (If you understood the previous sentence the first time your |
| 770 | * read it, you're overqualified for your current job.) |
| 771 | * |
| 772 | * In other words, @orig is mapped onto (surjectively) @dst, |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 773 | * using the map { <n, m> | the n-th bit of @relmap is the |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 774 | * m-th set bit of @relmap }. |
| 775 | * |
| 776 | * Any set bits in @orig above bit number W, where W is the |
| 777 | * weight of (number of set bits in) @relmap are mapped nowhere. |
| 778 | * In particular, if for all bits m set in @orig, m >= W, then |
| 779 | * @dst will end up empty. In situations where the possibility |
| 780 | * of such an empty result is not desired, one way to avoid it is |
| 781 | * to use the bitmap_fold() operator, below, to first fold the |
| 782 | * @orig bitmap over itself so that all its set bits x are in the |
| 783 | * range 0 <= x < W. The bitmap_fold() operator does this by |
| 784 | * setting the bit (m % W) in @dst, for each bit (m) set in @orig. |
| 785 | * |
| 786 | * Example [1] for bitmap_onto(): |
| 787 | * Let's say @relmap has bits 30-39 set, and @orig has bits |
| 788 | * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine, |
| 789 | * @dst will have bits 31, 33, 35, 37 and 39 set. |
| 790 | * |
| 791 | * When bit 0 is set in @orig, it means turn on the bit in |
| 792 | * @dst corresponding to whatever is the first bit (if any) |
| 793 | * that is turned on in @relmap. Since bit 0 was off in the |
| 794 | * above example, we leave off that bit (bit 30) in @dst. |
| 795 | * |
| 796 | * When bit 1 is set in @orig (as in the above example), it |
| 797 | * means turn on the bit in @dst corresponding to whatever |
| 798 | * is the second bit that is turned on in @relmap. The second |
| 799 | * bit in @relmap that was turned on in the above example was |
| 800 | * bit 31, so we turned on bit 31 in @dst. |
| 801 | * |
| 802 | * Similarly, we turned on bits 33, 35, 37 and 39 in @dst, |
| 803 | * because they were the 4th, 6th, 8th and 10th set bits |
| 804 | * set in @relmap, and the 4th, 6th, 8th and 10th bits of |
| 805 | * @orig (i.e. bits 3, 5, 7 and 9) were also set. |
| 806 | * |
| 807 | * When bit 11 is set in @orig, it means turn on the bit in |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 808 | * @dst corresponding to whatever is the twelfth bit that is |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 809 | * turned on in @relmap. In the above example, there were |
| 810 | * only ten bits turned on in @relmap (30..39), so that bit |
| 811 | * 11 was set in @orig had no affect on @dst. |
| 812 | * |
| 813 | * Example [2] for bitmap_fold() + bitmap_onto(): |
| 814 | * Let's say @relmap has these ten bits set: |
| 815 | * 40 41 42 43 45 48 53 61 74 95 |
| 816 | * (for the curious, that's 40 plus the first ten terms of the |
| 817 | * Fibonacci sequence.) |
| 818 | * |
| 819 | * Further lets say we use the following code, invoking |
| 820 | * bitmap_fold() then bitmap_onto, as suggested above to |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 821 | * avoid the possibility of an empty @dst result: |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 822 | * |
| 823 | * unsigned long *tmp; // a temporary bitmap's bits |
| 824 | * |
| 825 | * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits); |
| 826 | * bitmap_onto(dst, tmp, relmap, bits); |
| 827 | * |
| 828 | * Then this table shows what various values of @dst would be, for |
| 829 | * various @orig's. I list the zero-based positions of each set bit. |
| 830 | * The tmp column shows the intermediate result, as computed by |
| 831 | * using bitmap_fold() to fold the @orig bitmap modulo ten |
| 832 | * (the weight of @relmap). |
| 833 | * |
| 834 | * @orig tmp @dst |
| 835 | * 0 0 40 |
| 836 | * 1 1 41 |
| 837 | * 9 9 95 |
| 838 | * 10 0 40 (*) |
| 839 | * 1 3 5 7 1 3 5 7 41 43 48 61 |
| 840 | * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45 |
| 841 | * 0 9 18 27 0 9 8 7 40 61 74 95 |
| 842 | * 0 10 20 30 0 40 |
| 843 | * 0 11 22 33 0 1 2 3 40 41 42 43 |
| 844 | * 0 12 24 36 0 2 4 6 40 42 45 53 |
| 845 | * 78 102 211 1 2 8 41 42 74 (*) |
| 846 | * |
| 847 | * (*) For these marked lines, if we hadn't first done bitmap_fold() |
| 848 | * into tmp, then the @dst result would have been empty. |
| 849 | * |
| 850 | * If either of @orig or @relmap is empty (no set bits), then @dst |
| 851 | * will be returned empty. |
| 852 | * |
| 853 | * If (as explained above) the only set bits in @orig are in positions |
| 854 | * m where m >= W, (where W is the weight of @relmap) then @dst will |
| 855 | * once again be returned empty. |
| 856 | * |
| 857 | * All bits in @dst not set by the above rule are cleared. |
| 858 | */ |
| 859 | void bitmap_onto(unsigned long *dst, const unsigned long *orig, |
Rasmus Villemoes | eb56988 | 2015-02-12 15:02:01 -0800 | [diff] [blame] | 860 | const unsigned long *relmap, unsigned int bits) |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 861 | { |
Rasmus Villemoes | eb56988 | 2015-02-12 15:02:01 -0800 | [diff] [blame] | 862 | unsigned int n, m; /* same meaning as in above comment */ |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 863 | |
| 864 | if (dst == orig) /* following doesn't handle inplace mappings */ |
| 865 | return; |
| 866 | bitmap_zero(dst, bits); |
| 867 | |
| 868 | /* |
| 869 | * The following code is a more efficient, but less |
| 870 | * obvious, equivalent to the loop: |
| 871 | * for (m = 0; m < bitmap_weight(relmap, bits); m++) { |
| 872 | * n = bitmap_ord_to_pos(orig, m, bits); |
| 873 | * if (test_bit(m, orig)) |
| 874 | * set_bit(n, dst); |
| 875 | * } |
| 876 | */ |
| 877 | |
| 878 | m = 0; |
Akinobu Mita | 08564fb | 2010-03-05 13:43:18 -0800 | [diff] [blame] | 879 | for_each_set_bit(n, relmap, bits) { |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 880 | /* m == bitmap_pos_to_ord(relmap, n, bits) */ |
| 881 | if (test_bit(m, orig)) |
| 882 | set_bit(n, dst); |
| 883 | m++; |
| 884 | } |
| 885 | } |
| 886 | EXPORT_SYMBOL(bitmap_onto); |
| 887 | |
| 888 | /** |
| 889 | * bitmap_fold - fold larger bitmap into smaller, modulo specified size |
| 890 | * @dst: resulting smaller bitmap |
| 891 | * @orig: original larger bitmap |
| 892 | * @sz: specified size |
Rasmus Villemoes | b26ad58 | 2015-02-12 15:02:04 -0800 | [diff] [blame] | 893 | * @nbits: number of bits in each of these bitmaps |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 894 | * |
| 895 | * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst. |
| 896 | * Clear all other bits in @dst. See further the comment and |
| 897 | * Example [2] for bitmap_onto() for why and how to use this. |
| 898 | */ |
| 899 | void bitmap_fold(unsigned long *dst, const unsigned long *orig, |
Rasmus Villemoes | b26ad58 | 2015-02-12 15:02:04 -0800 | [diff] [blame] | 900 | unsigned int sz, unsigned int nbits) |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 901 | { |
Rasmus Villemoes | b26ad58 | 2015-02-12 15:02:04 -0800 | [diff] [blame] | 902 | unsigned int oldbit; |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 903 | |
| 904 | if (dst == orig) /* following doesn't handle inplace mappings */ |
| 905 | return; |
Rasmus Villemoes | b26ad58 | 2015-02-12 15:02:04 -0800 | [diff] [blame] | 906 | bitmap_zero(dst, nbits); |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 907 | |
Rasmus Villemoes | b26ad58 | 2015-02-12 15:02:04 -0800 | [diff] [blame] | 908 | for_each_set_bit(oldbit, orig, nbits) |
Paul Jackson | 7ea931c | 2008-04-28 02:12:29 -0700 | [diff] [blame] | 909 | set_bit(oldbit % sz, dst); |
| 910 | } |
| 911 | EXPORT_SYMBOL(bitmap_fold); |
| 912 | |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 913 | /* |
| 914 | * Common code for bitmap_*_region() routines. |
| 915 | * bitmap: array of unsigned longs corresponding to the bitmap |
| 916 | * pos: the beginning of the region |
| 917 | * order: region size (log base 2 of number of bits) |
| 918 | * reg_op: operation(s) to perform on that region of bitmap |
| 919 | * |
| 920 | * Can set, verify and/or release a region of bits in a bitmap, |
| 921 | * depending on which combination of REG_OP_* flag bits is set. |
| 922 | * |
| 923 | * A region of a bitmap is a sequence of bits in the bitmap, of |
| 924 | * some size '1 << order' (a power of two), aligned to that same |
| 925 | * '1 << order' power of two. |
| 926 | * |
| 927 | * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits). |
| 928 | * Returns 0 in all other cases and reg_ops. |
| 929 | */ |
| 930 | |
| 931 | enum { |
| 932 | REG_OP_ISFREE, /* true if region is all zero bits */ |
| 933 | REG_OP_ALLOC, /* set all bits in region */ |
| 934 | REG_OP_RELEASE, /* clear all bits in region */ |
| 935 | }; |
| 936 | |
Rasmus Villemoes | 9279d32 | 2014-08-06 16:10:16 -0700 | [diff] [blame] | 937 | static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op) |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 938 | { |
| 939 | int nbits_reg; /* number of bits in region */ |
| 940 | int index; /* index first long of region in bitmap */ |
| 941 | int offset; /* bit offset region in bitmap[index] */ |
| 942 | int nlongs_reg; /* num longs spanned by region in bitmap */ |
| 943 | int nbitsinlong; /* num bits of region in each spanned long */ |
| 944 | unsigned long mask; /* bitmask for one long of region */ |
| 945 | int i; /* scans bitmap by longs */ |
| 946 | int ret = 0; /* return value */ |
| 947 | |
| 948 | /* |
| 949 | * Either nlongs_reg == 1 (for small orders that fit in one long) |
| 950 | * or (offset == 0 && mask == ~0UL) (for larger multiword orders.) |
| 951 | */ |
| 952 | nbits_reg = 1 << order; |
| 953 | index = pos / BITS_PER_LONG; |
| 954 | offset = pos - (index * BITS_PER_LONG); |
| 955 | nlongs_reg = BITS_TO_LONGS(nbits_reg); |
| 956 | nbitsinlong = min(nbits_reg, BITS_PER_LONG); |
| 957 | |
| 958 | /* |
| 959 | * Can't do "mask = (1UL << nbitsinlong) - 1", as that |
| 960 | * overflows if nbitsinlong == BITS_PER_LONG. |
| 961 | */ |
| 962 | mask = (1UL << (nbitsinlong - 1)); |
| 963 | mask += mask - 1; |
| 964 | mask <<= offset; |
| 965 | |
| 966 | switch (reg_op) { |
| 967 | case REG_OP_ISFREE: |
| 968 | for (i = 0; i < nlongs_reg; i++) { |
| 969 | if (bitmap[index + i] & mask) |
| 970 | goto done; |
| 971 | } |
| 972 | ret = 1; /* all bits in region free (zero) */ |
| 973 | break; |
| 974 | |
| 975 | case REG_OP_ALLOC: |
| 976 | for (i = 0; i < nlongs_reg; i++) |
| 977 | bitmap[index + i] |= mask; |
| 978 | break; |
| 979 | |
| 980 | case REG_OP_RELEASE: |
| 981 | for (i = 0; i < nlongs_reg; i++) |
| 982 | bitmap[index + i] &= ~mask; |
| 983 | break; |
| 984 | } |
| 985 | done: |
| 986 | return ret; |
| 987 | } |
| 988 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | /** |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 990 | * bitmap_find_free_region - find a contiguous aligned mem region |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 991 | * @bitmap: array of unsigned longs corresponding to the bitmap |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 992 | * @bits: number of bits in the bitmap |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 993 | * @order: region size (log base 2 of number of bits) to find |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 994 | * |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 995 | * Find a region of free (zero) bits in a @bitmap of @bits bits and |
| 996 | * allocate them (set them to one). Only consider regions of length |
| 997 | * a power (@order) of two, aligned to that power of two, which |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 998 | * makes the search algorithm much faster. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 999 | * |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1000 | * Return the bit offset in bitmap of the allocated region, |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 1001 | * or -errno on failure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1002 | */ |
Rasmus Villemoes | 9279d32 | 2014-08-06 16:10:16 -0700 | [diff] [blame] | 1003 | int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1004 | { |
Rasmus Villemoes | 9279d32 | 2014-08-06 16:10:16 -0700 | [diff] [blame] | 1005 | unsigned int pos, end; /* scans bitmap by regions of size order */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1006 | |
Rasmus Villemoes | 9279d32 | 2014-08-06 16:10:16 -0700 | [diff] [blame] | 1007 | for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) { |
Linus Torvalds | aa8e4fc | 2009-03-12 19:32:51 -0700 | [diff] [blame] | 1008 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
| 1009 | continue; |
| 1010 | __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
| 1011 | return pos; |
| 1012 | } |
| 1013 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1014 | } |
| 1015 | EXPORT_SYMBOL(bitmap_find_free_region); |
| 1016 | |
| 1017 | /** |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 1018 | * bitmap_release_region - release allocated bitmap region |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1019 | * @bitmap: array of unsigned longs corresponding to the bitmap |
| 1020 | * @pos: beginning of bit region to release |
| 1021 | * @order: region size (log base 2 of number of bits) to release |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1022 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 1023 | * This is the complement to __bitmap_find_free_region() and releases |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1024 | * the found region (by clearing it in the bitmap). |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1025 | * |
| 1026 | * No return value. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | */ |
Rasmus Villemoes | 9279d32 | 2014-08-06 16:10:16 -0700 | [diff] [blame] | 1028 | void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1029 | { |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1030 | __reg_op(bitmap, pos, order, REG_OP_RELEASE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1031 | } |
| 1032 | EXPORT_SYMBOL(bitmap_release_region); |
| 1033 | |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 1034 | /** |
| 1035 | * bitmap_allocate_region - allocate bitmap region |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1036 | * @bitmap: array of unsigned longs corresponding to the bitmap |
| 1037 | * @pos: beginning of bit region to allocate |
| 1038 | * @order: region size (log base 2 of number of bits) to allocate |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 1039 | * |
| 1040 | * Allocate (set bits in) a specified region of a bitmap. |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1041 | * |
Randy Dunlap | 6e1907ff | 2006-06-25 05:48:57 -0700 | [diff] [blame] | 1042 | * Return 0 on success, or %-EBUSY if specified region wasn't |
Paul Jackson | 87e2480 | 2006-03-24 03:15:44 -0800 | [diff] [blame] | 1043 | * free (not all bits were zero). |
| 1044 | */ |
Rasmus Villemoes | 9279d32 | 2014-08-06 16:10:16 -0700 | [diff] [blame] | 1045 | int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1046 | { |
Paul Jackson | 3cf64b9 | 2006-03-24 03:15:46 -0800 | [diff] [blame] | 1047 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
| 1048 | return -EBUSY; |
Rasmus Villemoes | 2ac521d | 2014-08-06 16:10:18 -0700 | [diff] [blame] | 1049 | return __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1050 | } |
| 1051 | EXPORT_SYMBOL(bitmap_allocate_region); |
David Vrabel | ccbe329 | 2008-09-17 16:34:03 +0100 | [diff] [blame] | 1052 | |
| 1053 | /** |
| 1054 | * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. |
| 1055 | * @dst: destination buffer |
| 1056 | * @src: bitmap to copy |
| 1057 | * @nbits: number of bits in the bitmap |
| 1058 | * |
| 1059 | * Require nbits % BITS_PER_LONG == 0. |
| 1060 | */ |
Rasmus Villemoes | e8f2427 | 2015-02-13 14:36:00 -0800 | [diff] [blame] | 1061 | #ifdef __BIG_ENDIAN |
Rasmus Villemoes | 9b6c2d2 | 2015-02-13 14:35:57 -0800 | [diff] [blame] | 1062 | void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) |
David Vrabel | ccbe329 | 2008-09-17 16:34:03 +0100 | [diff] [blame] | 1063 | { |
Rasmus Villemoes | 9b6c2d2 | 2015-02-13 14:35:57 -0800 | [diff] [blame] | 1064 | unsigned int i; |
David Vrabel | ccbe329 | 2008-09-17 16:34:03 +0100 | [diff] [blame] | 1065 | |
| 1066 | for (i = 0; i < nbits/BITS_PER_LONG; i++) { |
| 1067 | if (BITS_PER_LONG == 64) |
Rasmus Villemoes | 9b6c2d2 | 2015-02-13 14:35:57 -0800 | [diff] [blame] | 1068 | dst[i] = cpu_to_le64(src[i]); |
David Vrabel | ccbe329 | 2008-09-17 16:34:03 +0100 | [diff] [blame] | 1069 | else |
Rasmus Villemoes | 9b6c2d2 | 2015-02-13 14:35:57 -0800 | [diff] [blame] | 1070 | dst[i] = cpu_to_le32(src[i]); |
David Vrabel | ccbe329 | 2008-09-17 16:34:03 +0100 | [diff] [blame] | 1071 | } |
| 1072 | } |
| 1073 | EXPORT_SYMBOL(bitmap_copy_le); |
Rasmus Villemoes | e8f2427 | 2015-02-13 14:36:00 -0800 | [diff] [blame] | 1074 | #endif |