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lib/bitmap.c
38.1 KB
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// SPDX-License-Identifier: GPL-2.0-only |
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/* * lib/bitmap.c * Helper functions for bitmap.h. |
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*/ |
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#include <linux/export.h> #include <linux/thread_info.h> |
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#include <linux/ctype.h> #include <linux/errno.h> #include <linux/bitmap.h> #include <linux/bitops.h> |
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#include <linux/bug.h> |
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#include <linux/kernel.h> |
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#include <linux/mm.h> |
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#include <linux/slab.h> |
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#include <linux/string.h> |
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#include <linux/uaccess.h> |
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#include <asm/page.h> |
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|
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#include "kstrtox.h" |
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/** * DOC: bitmap introduction * |
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* bitmaps provide an array of bits, implemented using an |
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* array of unsigned longs. The number of valid bits in a * given bitmap does _not_ need to be an exact multiple of * BITS_PER_LONG. * * The possible unused bits in the last, partially used word * of a bitmap are 'don't care'. The implementation makes * no particular effort to keep them zero. It ensures that * their value will not affect the results of any operation. * The bitmap operations that return Boolean (bitmap_empty, * for example) or scalar (bitmap_weight, for example) results * carefully filter out these unused bits from impacting their * results. * |
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* The byte ordering of bitmaps is more natural on little * endian architectures. See the big-endian headers * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h * for the best explanations of this ordering. */ |
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int __bitmap_equal(const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k, lim = bits/BITS_PER_LONG; |
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for (k = 0; k < lim; ++k) if (bitmap1[k] != bitmap2[k]) return 0; if (bits % BITS_PER_LONG) if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) return 0; return 1; } EXPORT_SYMBOL(__bitmap_equal); |
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bool __bitmap_or_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, const unsigned long *bitmap3, unsigned int bits) { unsigned int k, lim = bits / BITS_PER_LONG; unsigned long tmp; for (k = 0; k < lim; ++k) { if ((bitmap1[k] | bitmap2[k]) != bitmap3[k]) return false; } if (!(bits % BITS_PER_LONG)) return true; tmp = (bitmap1[k] | bitmap2[k]) ^ bitmap3[k]; return (tmp & BITMAP_LAST_WORD_MASK(bits)) == 0; } |
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void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits) |
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{ |
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unsigned int k, lim = BITS_TO_LONGS(bits); |
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for (k = 0; k < lim; ++k) dst[k] = ~src[k]; |
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} EXPORT_SYMBOL(__bitmap_complement); |
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/** |
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* __bitmap_shift_right - logical right shift of the bits in a bitmap |
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* @dst : destination bitmap * @src : source bitmap * @shift : shift by this many bits |
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* @nbits : bitmap size, in bits |
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* * Shifting right (dividing) means moving bits in the MS -> LS bit * direction. Zeros are fed into the vacated MS positions and the * LS bits shifted off the bottom are lost. */ |
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void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, unsigned shift, unsigned nbits) |
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{ |
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unsigned k, lim = BITS_TO_LONGS(nbits); |
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unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
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unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); |
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for (k = 0; off + k < lim; ++k) { unsigned long upper, lower; /* * If shift is not word aligned, take lower rem bits of * word above and make them the top rem bits of result. */ if (!rem || off + k + 1 >= lim) upper = 0; else { upper = src[off + k + 1]; |
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if (off + k + 1 == lim - 1) |
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upper &= mask; |
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upper <<= (BITS_PER_LONG - rem); |
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} lower = src[off + k]; |
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if (off + k == lim - 1) |
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lower &= mask; |
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lower >>= rem; dst[k] = lower | upper; |
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} if (off) memset(&dst[lim - off], 0, off*sizeof(unsigned long)); } EXPORT_SYMBOL(__bitmap_shift_right); |
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/** |
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* __bitmap_shift_left - logical left shift of the bits in a bitmap |
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* @dst : destination bitmap * @src : source bitmap * @shift : shift by this many bits |
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* @nbits : bitmap size, in bits |
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* * Shifting left (multiplying) means moving bits in the LS -> MS * direction. Zeros are fed into the vacated LS bit positions * and those MS bits shifted off the top are lost. */ |
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void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, unsigned int shift, unsigned int nbits) |
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{ |
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int k; |
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unsigned int lim = BITS_TO_LONGS(nbits); |
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unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
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for (k = lim - off - 1; k >= 0; --k) { unsigned long upper, lower; /* * If shift is not word aligned, take upper rem bits of * word below and make them the bottom rem bits of result. */ if (rem && k > 0) |
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lower = src[k - 1] >> (BITS_PER_LONG - rem); |
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else lower = 0; |
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upper = src[k] << rem; |
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dst[k + off] = lower | upper; |
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} if (off) memset(dst, 0, off*sizeof(unsigned long)); } EXPORT_SYMBOL(__bitmap_shift_left); |
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/** * bitmap_cut() - remove bit region from bitmap and right shift remaining bits * @dst: destination bitmap, might overlap with src * @src: source bitmap * @first: start bit of region to be removed * @cut: number of bits to remove * @nbits: bitmap size, in bits * * Set the n-th bit of @dst iff the n-th bit of @src is set and * n is less than @first, or the m-th bit of @src is set for any * m such that @first <= n < nbits, and m = n + @cut. * * In pictures, example for a big-endian 32-bit architecture: * |
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* The @src bitmap is:: |
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* |
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* 31 63 * | | * 10000000 11000001 11110010 00010101 10000000 11000001 01110010 00010101 * | | | | * 16 14 0 32 |
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* |
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* if @cut is 3, and @first is 14, bits 14-16 in @src are cut and @dst is:: * * 31 63 * | | * 10110000 00011000 00110010 00010101 00010000 00011000 00101110 01000010 * | | | * 14 (bit 17 0 32 * from @src) |
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* * Note that @dst and @src might overlap partially or entirely. * * This is implemented in the obvious way, with a shift and carry * step for each moved bit. Optimisation is left as an exercise * for the compiler. */ void bitmap_cut(unsigned long *dst, const unsigned long *src, unsigned int first, unsigned int cut, unsigned int nbits) { unsigned int len = BITS_TO_LONGS(nbits); unsigned long keep = 0, carry; int i; |
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if (first % BITS_PER_LONG) { keep = src[first / BITS_PER_LONG] & (~0UL >> (BITS_PER_LONG - first % BITS_PER_LONG)); } |
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memmove(dst, src, len * sizeof(*dst)); |
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while (cut--) { for (i = first / BITS_PER_LONG; i < len; i++) { if (i < len - 1) carry = dst[i + 1] & 1UL; else carry = 0; dst[i] = (dst[i] >> 1) | (carry << (BITS_PER_LONG - 1)); } } dst[first / BITS_PER_LONG] &= ~0UL << (first % BITS_PER_LONG); dst[first / BITS_PER_LONG] |= keep; } EXPORT_SYMBOL(bitmap_cut); |
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int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k; |
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unsigned int lim = bits/BITS_PER_LONG; |
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unsigned long result = 0; |
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|
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for (k = 0; k < lim; k++) |
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result |= (dst[k] = bitmap1[k] & bitmap2[k]); |
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if (bits % BITS_PER_LONG) result |= (dst[k] = bitmap1[k] & bitmap2[k] & BITMAP_LAST_WORD_MASK(bits)); |
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return result != 0; |
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} EXPORT_SYMBOL(__bitmap_and); void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k; unsigned int nr = BITS_TO_LONGS(bits); |
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for (k = 0; k < nr; k++) dst[k] = bitmap1[k] | bitmap2[k]; } EXPORT_SYMBOL(__bitmap_or); void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k; unsigned int nr = BITS_TO_LONGS(bits); |
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for (k = 0; k < nr; k++) dst[k] = bitmap1[k] ^ bitmap2[k]; } EXPORT_SYMBOL(__bitmap_xor); |
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int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k; |
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unsigned int lim = bits/BITS_PER_LONG; |
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unsigned long result = 0; |
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|
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for (k = 0; k < lim; k++) |
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result |= (dst[k] = bitmap1[k] & ~bitmap2[k]); |
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if (bits % BITS_PER_LONG) result |= (dst[k] = bitmap1[k] & ~bitmap2[k] & BITMAP_LAST_WORD_MASK(bits)); |
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return result != 0; |
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} EXPORT_SYMBOL(__bitmap_andnot); |
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void __bitmap_replace(unsigned long *dst, const unsigned long *old, const unsigned long *new, const unsigned long *mask, unsigned int nbits) { unsigned int k; unsigned int nr = BITS_TO_LONGS(nbits); for (k = 0; k < nr; k++) dst[k] = (old[k] & ~mask[k]) | (new[k] & mask[k]); } EXPORT_SYMBOL(__bitmap_replace); |
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int __bitmap_intersects(const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k, lim = bits/BITS_PER_LONG; |
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for (k = 0; k < lim; ++k) if (bitmap1[k] & bitmap2[k]) return 1; if (bits % BITS_PER_LONG) if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) return 1; return 0; } EXPORT_SYMBOL(__bitmap_intersects); int __bitmap_subset(const unsigned long *bitmap1, |
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const unsigned long *bitmap2, unsigned int bits) |
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{ |
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unsigned int k, lim = bits/BITS_PER_LONG; |
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for (k = 0; k < lim; ++k) if (bitmap1[k] & ~bitmap2[k]) return 0; if (bits % BITS_PER_LONG) if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) return 0; return 1; } EXPORT_SYMBOL(__bitmap_subset); |
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int __bitmap_weight(const unsigned long *bitmap, unsigned int bits) |
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{ |
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unsigned int k, lim = bits/BITS_PER_LONG; int w = 0; |
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for (k = 0; k < lim; k++) |
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w += hweight_long(bitmap[k]); |
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if (bits % BITS_PER_LONG) |
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w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits)); |
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return w; } |
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EXPORT_SYMBOL(__bitmap_weight); |
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void __bitmap_set(unsigned long *map, unsigned int start, int len) |
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{ unsigned long *p = map + BIT_WORD(start); |
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const unsigned int size = start + len; |
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int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); |
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while (len - bits_to_set >= 0) { |
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*p |= mask_to_set; |
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len -= bits_to_set; |
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bits_to_set = BITS_PER_LONG; mask_to_set = ~0UL; p++; } |
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if (len) { |
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mask_to_set &= BITMAP_LAST_WORD_MASK(size); *p |= mask_to_set; } } |
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EXPORT_SYMBOL(__bitmap_set); |
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|
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void __bitmap_clear(unsigned long *map, unsigned int start, int len) |
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{ unsigned long *p = map + BIT_WORD(start); |
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const unsigned int size = start + len; |
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int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); |
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while (len - bits_to_clear >= 0) { |
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*p &= ~mask_to_clear; |
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len -= bits_to_clear; |
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bits_to_clear = BITS_PER_LONG; mask_to_clear = ~0UL; p++; } |
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if (len) { |
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mask_to_clear &= BITMAP_LAST_WORD_MASK(size); *p &= ~mask_to_clear; } } |
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EXPORT_SYMBOL(__bitmap_clear); |
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|
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/** * bitmap_find_next_zero_area_off - find a contiguous aligned zero area |
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* @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @align_mask: Alignment mask for zero area |
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* @align_offset: Alignment offset for zero area. |
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* * The @align_mask should be one less than a power of 2; the effect is that |
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* the bit offset of all zero areas this function finds plus @align_offset * is multiple of that power of 2. |
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*/ |
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unsigned long bitmap_find_next_zero_area_off(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, unsigned long align_mask, unsigned long align_offset) |
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{ unsigned long index, end, i; again: index = find_next_zero_bit(map, size, start); /* Align allocation */ |
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index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset; |
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end = index + nr; if (end > size) return end; i = find_next_bit(map, end, index); if (i < end) { start = i + 1; goto again; } return index; } |
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EXPORT_SYMBOL(bitmap_find_next_zero_area_off); |
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|
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/* |
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* Bitmap printing & parsing functions: first version by Nadia Yvette Chambers, |
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* second version by Paul Jackson, third by Joe Korty. */ |
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/** |
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* bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap |
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* * @ubuf: pointer to user buffer containing string. * @ulen: buffer size in bytes. If string is smaller than this * then it must be terminated with a \0. * @maskp: pointer to bitmap array that will contain result. * @nmaskbits: size of bitmap, in bits. |
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*/ int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { |
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char *buf; int ret; buf = memdup_user_nul(ubuf, ulen); if (IS_ERR(buf)) return PTR_ERR(buf); |
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ret = bitmap_parse(buf, UINT_MAX, maskp, nmaskbits); |
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kfree(buf); return ret; |
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} EXPORT_SYMBOL(bitmap_parse_user); |
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/** |
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* bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string * @list: indicates whether the bitmap must be list * @buf: page aligned buffer into which string is placed * @maskp: pointer to bitmap to convert * @nmaskbits: size of bitmap, in bits * * Output format is a comma-separated list of decimal numbers and * ranges if list is specified or hex digits grouped into comma-separated * sets of 8 digits/set. Returns the number of characters written to buf. |
9cf79d115 bitmap: remove ex... |
450 |
* |
ce1091d47 lib/bitmap.c: fix... |
451 452 453 454 |
* It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned * area and that sufficient storage remains at @buf to accommodate the * bitmap_print_to_pagebuf() output. Returns the number of characters * actually printed to @buf, excluding terminating '\0'. |
5aaba3631 cpumask: factor o... |
455 456 457 458 |
*/ int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, int nmaskbits) { |
ce1091d47 lib/bitmap.c: fix... |
459 |
ptrdiff_t len = PAGE_SIZE - offset_in_page(buf); |
5aaba3631 cpumask: factor o... |
460 |
|
8ec3d7686 lib/bitmap.c: sim... |
461 462 463 464 |
return list ? scnprintf(buf, len, "%*pbl ", nmaskbits, maskp) : scnprintf(buf, len, "%*pb ", nmaskbits, maskp); |
5aaba3631 cpumask: factor o... |
465 466 |
} EXPORT_SYMBOL(bitmap_print_to_pagebuf); |
e371c481d lib: rework bitma... |
467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 |
/* * Region 9-38:4/10 describes the following bitmap structure: * 0 9 12 18 38 * .........****......****......****...... * ^ ^ ^ ^ * start off group_len end */ struct region { unsigned int start; unsigned int off; unsigned int group_len; unsigned int end; }; static int bitmap_set_region(const struct region *r, unsigned long *bitmap, int nbits) { unsigned int start; if (r->end >= nbits) return -ERANGE; for (start = r->start; start <= r->end; start += r->group_len) bitmap_set(bitmap, start, min(r->end - start + 1, r->off)); return 0; } static int bitmap_check_region(const struct region *r) { if (r->start > r->end || r->group_len == 0 || r->off > r->group_len) return -EINVAL; return 0; } static const char *bitmap_getnum(const char *str, unsigned int *num) { unsigned long long n; unsigned int len; len = _parse_integer(str, 10, &n); if (!len) return ERR_PTR(-EINVAL); if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n) return ERR_PTR(-EOVERFLOW); *num = n; return str + len; } static inline bool end_of_str(char c) { return c == '\0' || c == ' '; } static inline bool __end_of_region(char c) { return isspace(c) || c == ','; } static inline bool end_of_region(char c) { return __end_of_region(c) || end_of_str(c); } /* |
206074341 lib/bitmap.c: fix... |
535 |
* The format allows commas and whitespaces at the beginning |
e371c481d lib: rework bitma... |
536 537 538 539 540 541 542 543 544 |
* of the region. */ static const char *bitmap_find_region(const char *str) { while (__end_of_region(*str)) str++; return end_of_str(*str) ? NULL : str; } |
2d6261583 lib: rework bitma... |
545 546 547 548 549 550 551 |
static const char *bitmap_find_region_reverse(const char *start, const char *end) { while (start <= end && __end_of_region(*end)) end--; return end; } |
e371c481d lib: rework bitma... |
552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 |
static const char *bitmap_parse_region(const char *str, struct region *r) { str = bitmap_getnum(str, &r->start); if (IS_ERR(str)) return str; if (end_of_region(*str)) goto no_end; if (*str != '-') return ERR_PTR(-EINVAL); str = bitmap_getnum(str + 1, &r->end); if (IS_ERR(str)) return str; if (end_of_region(*str)) goto no_pattern; if (*str != ':') return ERR_PTR(-EINVAL); str = bitmap_getnum(str + 1, &r->off); if (IS_ERR(str)) return str; if (*str != '/') return ERR_PTR(-EINVAL); return bitmap_getnum(str + 1, &r->group_len); no_end: r->end = r->start; no_pattern: r->off = r->end + 1; r->group_len = r->end + 1; return end_of_str(*str) ? NULL : str; } |
5aaba3631 cpumask: factor o... |
591 |
/** |
e371c481d lib: rework bitma... |
592 593 594 595 |
* bitmap_parselist - convert list format ASCII string to bitmap * @buf: read user string from this buffer; must be terminated * with a \0 or . |
6e1907ffd [PATCH] kernel-do... |
596 |
* @maskp: write resulting mask here |
1da177e4c Linux-2.6.12-rc2 |
597 598 599 600 601 602 |
* @nmaskbits: number of bits in mask to be written * * Input format is a comma-separated list of decimal numbers and * ranges. Consecutively set bits are shown as two hyphen-separated * decimal numbers, the smallest and largest bit numbers set in * the range. |
2d13e6ca4 lib/bitmap.c: enh... |
603 604 605 606 607 |
* Optionally each range can be postfixed to denote that only parts of it * should be set. The range will divided to groups of specific size. * From each group will be used only defined amount of bits. * Syntax: range:used_size/group_size * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 |
1da177e4c Linux-2.6.12-rc2 |
608 |
* |
40bf19a8d kernel-api.rst: f... |
609 610 |
* Returns: 0 on success, -errno on invalid input strings. Error values: * |
e371c481d lib: rework bitma... |
611 |
* - ``-EINVAL``: wrong region format |
40bf19a8d kernel-api.rst: f... |
612 613 |
* - ``-EINVAL``: invalid character in string * - ``-ERANGE``: bit number specified too large for mask |
e371c481d lib: rework bitma... |
614 |
* - ``-EOVERFLOW``: integer overflow in the input parameters |
1da177e4c Linux-2.6.12-rc2 |
615 |
*/ |
e371c481d lib: rework bitma... |
616 |
int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) |
1da177e4c Linux-2.6.12-rc2 |
617 |
{ |
e371c481d lib: rework bitma... |
618 619 |
struct region r; long ret; |
1da177e4c Linux-2.6.12-rc2 |
620 621 |
bitmap_zero(maskp, nmaskbits); |
4b060420a bitmap, irq: add ... |
622 |
|
e371c481d lib: rework bitma... |
623 624 625 626 |
while (buf) { buf = bitmap_find_region(buf); if (buf == NULL) return 0; |
2d13e6ca4 lib/bitmap.c: enh... |
627 |
|
e371c481d lib: rework bitma... |
628 629 630 |
buf = bitmap_parse_region(buf, &r); if (IS_ERR(buf)) return PTR_ERR(buf); |
2d13e6ca4 lib/bitmap.c: enh... |
631 |
|
e371c481d lib: rework bitma... |
632 633 634 |
ret = bitmap_check_region(&r); if (ret) return ret; |
4b060420a bitmap, irq: add ... |
635 |
|
e371c481d lib: rework bitma... |
636 637 638 639 |
ret = bitmap_set_region(&r, maskp, nmaskbits); if (ret) return ret; } |
4b060420a bitmap, irq: add ... |
640 |
|
1da177e4c Linux-2.6.12-rc2 |
641 642 643 |
return 0; } EXPORT_SYMBOL(bitmap_parselist); |
4b060420a bitmap, irq: add ... |
644 645 646 647 648 649 650 651 652 653 654 |
/** * bitmap_parselist_user() * * @ubuf: pointer to user buffer containing string. * @ulen: buffer size in bytes. If string is smaller than this * then it must be terminated with a \0. * @maskp: pointer to bitmap array that will contain result. * @nmaskbits: size of bitmap, in bits. * * Wrapper for bitmap_parselist(), providing it with user buffer. |
4b060420a bitmap, irq: add ... |
655 656 657 658 659 |
*/ int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { |
281327c99 lib: make bitmap_... |
660 661 662 663 664 665 666 667 668 669 670 |
char *buf; int ret; buf = memdup_user_nul(ubuf, ulen); if (IS_ERR(buf)) return PTR_ERR(buf); ret = bitmap_parselist(buf, maskp, nmaskbits); kfree(buf); return ret; |
4b060420a bitmap, irq: add ... |
671 672 |
} EXPORT_SYMBOL(bitmap_parselist_user); |
2d6261583 lib: rework bitma... |
673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 |
static const char *bitmap_get_x32_reverse(const char *start, const char *end, u32 *num) { u32 ret = 0; int c, i; for (i = 0; i < 32; i += 4) { c = hex_to_bin(*end--); if (c < 0) return ERR_PTR(-EINVAL); ret |= c << i; if (start > end || __end_of_region(*end)) goto out; } if (hex_to_bin(*end--) >= 0) return ERR_PTR(-EOVERFLOW); out: *num = ret; return end; } /** * bitmap_parse - convert an ASCII hex string into a bitmap. * @start: pointer to buffer containing string. * @buflen: buffer size in bytes. If string is smaller than this * then it must be terminated with a \0 or . In that case, * UINT_MAX may be provided instead of string length. * @maskp: pointer to bitmap array that will contain result. * @nmaskbits: size of bitmap, in bits. * * Commas group hex digits into chunks. Each chunk defines exactly 32 * bits of the resultant bitmask. No chunk may specify a value larger * than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value * then leading 0-bits are prepended. %-EINVAL is returned for illegal * characters. Grouping such as "1,,5", ",44", "," or "" is allowed. * Leading, embedded and trailing whitespace accepted. */ int bitmap_parse(const char *start, unsigned int buflen, unsigned long *maskp, int nmaskbits) { const char *end = strnchrnul(start, buflen, ' ') - 1; int chunks = BITS_TO_U32(nmaskbits); u32 *bitmap = (u32 *)maskp; int unset_bit; |
81c4f4d92 lib: fix bitmap_p... |
722 |
int chunk; |
2d6261583 lib: rework bitma... |
723 |
|
81c4f4d92 lib: fix bitmap_p... |
724 |
for (chunk = 0; ; chunk++) { |
2d6261583 lib: rework bitma... |
725 726 727 728 729 730 |
end = bitmap_find_region_reverse(start, end); if (start > end) break; if (!chunks--) return -EOVERFLOW; |
81c4f4d92 lib: fix bitmap_p... |
731 732 733 734 735 |
#if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) end = bitmap_get_x32_reverse(start, end, &bitmap[chunk ^ 1]); #else end = bitmap_get_x32_reverse(start, end, &bitmap[chunk]); #endif |
2d6261583 lib: rework bitma... |
736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 |
if (IS_ERR(end)) return PTR_ERR(end); } unset_bit = (BITS_TO_U32(nmaskbits) - chunks) * 32; if (unset_bit < nmaskbits) { bitmap_clear(maskp, unset_bit, nmaskbits - unset_bit); return 0; } if (find_next_bit(maskp, unset_bit, nmaskbits) != unset_bit) return -EOVERFLOW; return 0; } EXPORT_SYMBOL(bitmap_parse); |
4b060420a bitmap, irq: add ... |
752 |
|
cdc90a187 lib/bitmap.c: gua... |
753 |
#ifdef CONFIG_NUMA |
72fd4a35a [PATCH] Numerous ... |
754 |
/** |
9a86e2bad lib: fix first li... |
755 |
* bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap |
fb5eeeee4 [PATCH] cpusets: ... |
756 |
* @buf: pointer to a bitmap |
df1d80a9e lib/bitmap.c: sim... |
757 758 |
* @pos: a bit position in @buf (0 <= @pos < @nbits) * @nbits: number of valid bit positions in @buf |
fb5eeeee4 [PATCH] cpusets: ... |
759 |
* |
df1d80a9e lib/bitmap.c: sim... |
760 |
* Map the bit at position @pos in @buf (of length @nbits) to the |
fb5eeeee4 [PATCH] cpusets: ... |
761 |
* ordinal of which set bit it is. If it is not set or if @pos |
96b7f3414 [PATCH] cpuset: b... |
762 |
* is not a valid bit position, map to -1. |
fb5eeeee4 [PATCH] cpusets: ... |
763 764 765 |
* * If for example, just bits 4 through 7 are set in @buf, then @pos * values 4 through 7 will get mapped to 0 through 3, respectively, |
a85517487 lib: bitmap: fix ... |
766 |
* and other @pos values will get mapped to -1. When @pos value 7 |
fb5eeeee4 [PATCH] cpusets: ... |
767 768 769 770 771 |
* gets mapped to (returns) @ord value 3 in this example, that means * that bit 7 is the 3rd (starting with 0th) set bit in @buf. * * The bit positions 0 through @bits are valid positions in @buf. */ |
df1d80a9e lib/bitmap.c: sim... |
772 |
static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits) |
fb5eeeee4 [PATCH] cpusets: ... |
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{ |
df1d80a9e lib/bitmap.c: sim... |
774 |
if (pos >= nbits || !test_bit(pos, buf)) |
96b7f3414 [PATCH] cpuset: b... |
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return -1; |
fb5eeeee4 [PATCH] cpusets: ... |
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|
df1d80a9e lib/bitmap.c: sim... |
777 |
return __bitmap_weight(buf, pos); |
fb5eeeee4 [PATCH] cpusets: ... |
778 779 780 |
} /** |
9a86e2bad lib: fix first li... |
781 |
* bitmap_ord_to_pos - find position of n-th set bit in bitmap |
fb5eeeee4 [PATCH] cpusets: ... |
782 783 |
* @buf: pointer to bitmap * @ord: ordinal bit position (n-th set bit, n >= 0) |
f6a1f5db8 lib/bitmap.c: sim... |
784 |
* @nbits: number of valid bit positions in @buf |
fb5eeeee4 [PATCH] cpusets: ... |
785 786 |
* * Map the ordinal offset of bit @ord in @buf to its position in @buf. |
f6a1f5db8 lib/bitmap.c: sim... |
787 788 |
* Value of @ord should be in range 0 <= @ord < weight(buf). If @ord * >= weight(buf), returns @nbits. |
fb5eeeee4 [PATCH] cpusets: ... |
789 790 791 |
* * If for example, just bits 4 through 7 are set in @buf, then @ord * values 0 through 3 will get mapped to 4 through 7, respectively, |
f6a1f5db8 lib/bitmap.c: sim... |
792 |
* and all other @ord values returns @nbits. When @ord value 3 |
fb5eeeee4 [PATCH] cpusets: ... |
793 794 795 |
* gets mapped to (returns) @pos value 7 in this example, that means * that the 3rd set bit (starting with 0th) is at position 7 in @buf. * |
f6a1f5db8 lib/bitmap.c: sim... |
796 |
* The bit positions 0 through @nbits-1 are valid positions in @buf. |
fb5eeeee4 [PATCH] cpusets: ... |
797 |
*/ |
f6a1f5db8 lib/bitmap.c: sim... |
798 |
unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits) |
fb5eeeee4 [PATCH] cpusets: ... |
799 |
{ |
f6a1f5db8 lib/bitmap.c: sim... |
800 |
unsigned int pos; |
fb5eeeee4 [PATCH] cpusets: ... |
801 |
|
f6a1f5db8 lib/bitmap.c: sim... |
802 803 804 805 |
for (pos = find_first_bit(buf, nbits); pos < nbits && ord; pos = find_next_bit(buf, nbits, pos + 1)) ord--; |
fb5eeeee4 [PATCH] cpusets: ... |
806 807 808 809 810 811 |
return pos; } /** * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap |
fb5eeeee4 [PATCH] cpusets: ... |
812 |
* @dst: remapped result |
96b7f3414 [PATCH] cpuset: b... |
813 |
* @src: subset to be remapped |
fb5eeeee4 [PATCH] cpusets: ... |
814 815 |
* @old: defines domain of map * @new: defines range of map |
9814ec135 lib/bitmap.c: mak... |
816 |
* @nbits: number of bits in each of these bitmaps |
fb5eeeee4 [PATCH] cpusets: ... |
817 818 819 820 821 822 823 824 |
* * Let @old and @new define a mapping of bit positions, such that * whatever position is held by the n-th set bit in @old is mapped * to the n-th set bit in @new. In the more general case, allowing * for the possibility that the weight 'w' of @new is less than the * weight of @old, map the position of the n-th set bit in @old to * the position of the m-th set bit in @new, where m == n % w. * |
96b7f3414 [PATCH] cpuset: b... |
825 826 827 |
* If either of the @old and @new bitmaps are empty, or if @src and * @dst point to the same location, then this routine copies @src * to @dst. |
fb5eeeee4 [PATCH] cpusets: ... |
828 |
* |
96b7f3414 [PATCH] cpuset: b... |
829 830 |
* The positions of unset bits in @old are mapped to themselves * (the identify map). |
fb5eeeee4 [PATCH] cpusets: ... |
831 832 833 834 |
* * Apply the above specified mapping to @src, placing the result in * @dst, clearing any bits previously set in @dst. * |
fb5eeeee4 [PATCH] cpusets: ... |
835 836 837 |
* For example, lets say that @old has bits 4 through 7 set, and * @new has bits 12 through 15 set. This defines the mapping of bit * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other |
96b7f3414 [PATCH] cpuset: b... |
838 839 840 |
* bit positions unchanged. So if say @src comes into this routine * with bits 1, 5 and 7 set, then @dst should leave with bits 1, * 13 and 15 set. |
fb5eeeee4 [PATCH] cpusets: ... |
841 842 843 |
*/ void bitmap_remap(unsigned long *dst, const unsigned long *src, const unsigned long *old, const unsigned long *new, |
9814ec135 lib/bitmap.c: mak... |
844 |
unsigned int nbits) |
fb5eeeee4 [PATCH] cpusets: ... |
845 |
{ |
9814ec135 lib/bitmap.c: mak... |
846 |
unsigned int oldbit, w; |
fb5eeeee4 [PATCH] cpusets: ... |
847 |
|
fb5eeeee4 [PATCH] cpusets: ... |
848 849 |
if (dst == src) /* following doesn't handle inplace remaps */ return; |
9814ec135 lib/bitmap.c: mak... |
850 |
bitmap_zero(dst, nbits); |
96b7f3414 [PATCH] cpuset: b... |
851 |
|
9814ec135 lib/bitmap.c: mak... |
852 853 854 |
w = bitmap_weight(new, nbits); for_each_set_bit(oldbit, src, nbits) { int n = bitmap_pos_to_ord(old, oldbit, nbits); |
08564fb7a bitmap: use for_e... |
855 |
|
96b7f3414 [PATCH] cpuset: b... |
856 857 858 |
if (n < 0 || w == 0) set_bit(oldbit, dst); /* identity map */ else |
9814ec135 lib/bitmap.c: mak... |
859 |
set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst); |
fb5eeeee4 [PATCH] cpusets: ... |
860 861 |
} } |
fb5eeeee4 [PATCH] cpusets: ... |
862 863 864 |
/** * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit |
6e1907ffd [PATCH] kernel-do... |
865 866 867 868 |
* @oldbit: bit position to be mapped * @old: defines domain of map * @new: defines range of map * @bits: number of bits in each of these bitmaps |
fb5eeeee4 [PATCH] cpusets: ... |
869 870 871 872 873 874 875 876 |
* * Let @old and @new define a mapping of bit positions, such that * whatever position is held by the n-th set bit in @old is mapped * to the n-th set bit in @new. In the more general case, allowing * for the possibility that the weight 'w' of @new is less than the * weight of @old, map the position of the n-th set bit in @old to * the position of the m-th set bit in @new, where m == n % w. * |
96b7f3414 [PATCH] cpuset: b... |
877 878 |
* The positions of unset bits in @old are mapped to themselves * (the identify map). |
fb5eeeee4 [PATCH] cpusets: ... |
879 880 881 882 883 884 885 |
* * Apply the above specified mapping to bit position @oldbit, returning * the new bit position. * * For example, lets say that @old has bits 4 through 7 set, and * @new has bits 12 through 15 set. This defines the mapping of bit * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other |
96b7f3414 [PATCH] cpuset: b... |
886 887 |
* bit positions unchanged. So if say @oldbit is 5, then this routine * returns 13. |
fb5eeeee4 [PATCH] cpusets: ... |
888 889 890 891 |
*/ int bitmap_bitremap(int oldbit, const unsigned long *old, const unsigned long *new, int bits) { |
96b7f3414 [PATCH] cpuset: b... |
892 893 894 895 896 897 |
int w = bitmap_weight(new, bits); int n = bitmap_pos_to_ord(old, oldbit, bits); if (n < 0 || w == 0) return oldbit; else return bitmap_ord_to_pos(new, n % w, bits); |
fb5eeeee4 [PATCH] cpusets: ... |
898 |
} |
fb5eeeee4 [PATCH] cpusets: ... |
899 |
|
7ea931c9f mempolicy: add bi... |
900 901 902 903 904 905 906 907 908 909 910 911 912 913 |
/** * bitmap_onto - translate one bitmap relative to another * @dst: resulting translated bitmap * @orig: original untranslated bitmap * @relmap: bitmap relative to which translated * @bits: number of bits in each of these bitmaps * * Set the n-th bit of @dst iff there exists some m such that the * n-th bit of @relmap is set, the m-th bit of @orig is set, and * the n-th bit of @relmap is also the m-th _set_ bit of @relmap. * (If you understood the previous sentence the first time your * read it, you're overqualified for your current job.) * * In other words, @orig is mapped onto (surjectively) @dst, |
da3dae54e Documentation: Do... |
914 |
* using the map { <n, m> | the n-th bit of @relmap is the |
7ea931c9f mempolicy: add bi... |
915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 |
* m-th set bit of @relmap }. * * Any set bits in @orig above bit number W, where W is the * weight of (number of set bits in) @relmap are mapped nowhere. * In particular, if for all bits m set in @orig, m >= W, then * @dst will end up empty. In situations where the possibility * of such an empty result is not desired, one way to avoid it is * to use the bitmap_fold() operator, below, to first fold the * @orig bitmap over itself so that all its set bits x are in the * range 0 <= x < W. The bitmap_fold() operator does this by * setting the bit (m % W) in @dst, for each bit (m) set in @orig. * * Example [1] for bitmap_onto(): * Let's say @relmap has bits 30-39 set, and @orig has bits * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine, * @dst will have bits 31, 33, 35, 37 and 39 set. * * When bit 0 is set in @orig, it means turn on the bit in * @dst corresponding to whatever is the first bit (if any) * that is turned on in @relmap. Since bit 0 was off in the * above example, we leave off that bit (bit 30) in @dst. * * When bit 1 is set in @orig (as in the above example), it * means turn on the bit in @dst corresponding to whatever * is the second bit that is turned on in @relmap. The second * bit in @relmap that was turned on in the above example was * bit 31, so we turned on bit 31 in @dst. * * Similarly, we turned on bits 33, 35, 37 and 39 in @dst, * because they were the 4th, 6th, 8th and 10th set bits * set in @relmap, and the 4th, 6th, 8th and 10th bits of * @orig (i.e. bits 3, 5, 7 and 9) were also set. * * When bit 11 is set in @orig, it means turn on the bit in |
25985edce Fix common misspe... |
949 |
* @dst corresponding to whatever is the twelfth bit that is |
7ea931c9f mempolicy: add bi... |
950 951 952 953 954 |
* turned on in @relmap. In the above example, there were * only ten bits turned on in @relmap (30..39), so that bit * 11 was set in @orig had no affect on @dst. * * Example [2] for bitmap_fold() + bitmap_onto(): |
40bf19a8d kernel-api.rst: f... |
955 956 |
* Let's say @relmap has these ten bits set:: * |
7ea931c9f mempolicy: add bi... |
957 |
* 40 41 42 43 45 48 53 61 74 95 |
40bf19a8d kernel-api.rst: f... |
958 |
* |
7ea931c9f mempolicy: add bi... |
959 960 961 962 963 |
* (for the curious, that's 40 plus the first ten terms of the * Fibonacci sequence.) * * Further lets say we use the following code, invoking * bitmap_fold() then bitmap_onto, as suggested above to |
40bf19a8d kernel-api.rst: f... |
964 |
* avoid the possibility of an empty @dst result:: |
7ea931c9f mempolicy: add bi... |
965 966 967 968 969 970 971 972 973 974 |
* * unsigned long *tmp; // a temporary bitmap's bits * * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits); * bitmap_onto(dst, tmp, relmap, bits); * * Then this table shows what various values of @dst would be, for * various @orig's. I list the zero-based positions of each set bit. * The tmp column shows the intermediate result, as computed by * using bitmap_fold() to fold the @orig bitmap modulo ten |
40bf19a8d kernel-api.rst: f... |
975 |
* (the weight of @relmap): |
7ea931c9f mempolicy: add bi... |
976 |
* |
40bf19a8d kernel-api.rst: f... |
977 |
* =============== ============== ================= |
7ea931c9f mempolicy: add bi... |
978 979 980 981 |
* @orig tmp @dst * 0 0 40 * 1 1 41 * 9 9 95 |
40bf19a8d kernel-api.rst: f... |
982 |
* 10 0 40 [#f1]_ |
7ea931c9f mempolicy: add bi... |
983 984 985 986 987 988 |
* 1 3 5 7 1 3 5 7 41 43 48 61 * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45 * 0 9 18 27 0 9 8 7 40 61 74 95 * 0 10 20 30 0 40 * 0 11 22 33 0 1 2 3 40 41 42 43 * 0 12 24 36 0 2 4 6 40 42 45 53 |
40bf19a8d kernel-api.rst: f... |
989 990 991 992 |
* 78 102 211 1 2 8 41 42 74 [#f1]_ * =============== ============== ================= * * .. [#f1] |
7ea931c9f mempolicy: add bi... |
993 |
* |
40bf19a8d kernel-api.rst: f... |
994 |
* For these marked lines, if we hadn't first done bitmap_fold() |
7ea931c9f mempolicy: add bi... |
995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 |
* into tmp, then the @dst result would have been empty. * * If either of @orig or @relmap is empty (no set bits), then @dst * will be returned empty. * * If (as explained above) the only set bits in @orig are in positions * m where m >= W, (where W is the weight of @relmap) then @dst will * once again be returned empty. * * All bits in @dst not set by the above rule are cleared. */ void bitmap_onto(unsigned long *dst, const unsigned long *orig, |
eb5698837 lib/bitmap.c: upd... |
1007 |
const unsigned long *relmap, unsigned int bits) |
7ea931c9f mempolicy: add bi... |
1008 |
{ |
eb5698837 lib/bitmap.c: upd... |
1009 |
unsigned int n, m; /* same meaning as in above comment */ |
7ea931c9f mempolicy: add bi... |
1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 |
if (dst == orig) /* following doesn't handle inplace mappings */ return; bitmap_zero(dst, bits); /* * The following code is a more efficient, but less * obvious, equivalent to the loop: * for (m = 0; m < bitmap_weight(relmap, bits); m++) { * n = bitmap_ord_to_pos(orig, m, bits); * if (test_bit(m, orig)) * set_bit(n, dst); * } */ m = 0; |
08564fb7a bitmap: use for_e... |
1026 |
for_each_set_bit(n, relmap, bits) { |
7ea931c9f mempolicy: add bi... |
1027 1028 1029 1030 1031 1032 |
/* m == bitmap_pos_to_ord(relmap, n, bits) */ if (test_bit(m, orig)) set_bit(n, dst); m++; } } |
7ea931c9f mempolicy: add bi... |
1033 1034 1035 1036 1037 1038 |
/** * bitmap_fold - fold larger bitmap into smaller, modulo specified size * @dst: resulting smaller bitmap * @orig: original larger bitmap * @sz: specified size |
b26ad5836 lib/bitmap.c: cha... |
1039 |
* @nbits: number of bits in each of these bitmaps |
7ea931c9f mempolicy: add bi... |
1040 1041 1042 1043 1044 1045 |
* * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst. * Clear all other bits in @dst. See further the comment and * Example [2] for bitmap_onto() for why and how to use this. */ void bitmap_fold(unsigned long *dst, const unsigned long *orig, |
b26ad5836 lib/bitmap.c: cha... |
1046 |
unsigned int sz, unsigned int nbits) |
7ea931c9f mempolicy: add bi... |
1047 |
{ |
b26ad5836 lib/bitmap.c: cha... |
1048 |
unsigned int oldbit; |
7ea931c9f mempolicy: add bi... |
1049 1050 1051 |
if (dst == orig) /* following doesn't handle inplace mappings */ return; |
b26ad5836 lib/bitmap.c: cha... |
1052 |
bitmap_zero(dst, nbits); |
7ea931c9f mempolicy: add bi... |
1053 |
|
b26ad5836 lib/bitmap.c: cha... |
1054 |
for_each_set_bit(oldbit, orig, nbits) |
7ea931c9f mempolicy: add bi... |
1055 1056 |
set_bit(oldbit % sz, dst); } |
cdc90a187 lib/bitmap.c: gua... |
1057 |
#endif /* CONFIG_NUMA */ |
7ea931c9f mempolicy: add bi... |
1058 |
|
3cf64b933 [PATCH] bitmap: r... |
1059 1060 1061 1062 1063 1064 |
/* * Common code for bitmap_*_region() routines. * bitmap: array of unsigned longs corresponding to the bitmap * pos: the beginning of the region * order: region size (log base 2 of number of bits) * reg_op: operation(s) to perform on that region of bitmap |
1da177e4c Linux-2.6.12-rc2 |
1065 |
* |
3cf64b933 [PATCH] bitmap: r... |
1066 1067 |
* Can set, verify and/or release a region of bits in a bitmap, * depending on which combination of REG_OP_* flag bits is set. |
1da177e4c Linux-2.6.12-rc2 |
1068 |
* |
3cf64b933 [PATCH] bitmap: r... |
1069 1070 1071 1072 1073 1074 |
* A region of a bitmap is a sequence of bits in the bitmap, of * some size '1 << order' (a power of two), aligned to that same * '1 << order' power of two. * * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits). * Returns 0 in all other cases and reg_ops. |
1da177e4c Linux-2.6.12-rc2 |
1075 |
*/ |
3cf64b933 [PATCH] bitmap: r... |
1076 1077 1078 1079 1080 1081 |
enum { REG_OP_ISFREE, /* true if region is all zero bits */ REG_OP_ALLOC, /* set all bits in region */ REG_OP_RELEASE, /* clear all bits in region */ }; |
9279d3286 lib: bitmap: chan... |
1082 |
static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op) |
1da177e4c Linux-2.6.12-rc2 |
1083 |
{ |
3cf64b933 [PATCH] bitmap: r... |
1084 1085 1086 1087 |
int nbits_reg; /* number of bits in region */ int index; /* index first long of region in bitmap */ int offset; /* bit offset region in bitmap[index] */ int nlongs_reg; /* num longs spanned by region in bitmap */ |
74373c6ac [PATCH] bitmap: r... |
1088 |
int nbitsinlong; /* num bits of region in each spanned long */ |
3cf64b933 [PATCH] bitmap: r... |
1089 |
unsigned long mask; /* bitmask for one long of region */ |
74373c6ac [PATCH] bitmap: r... |
1090 |
int i; /* scans bitmap by longs */ |
3cf64b933 [PATCH] bitmap: r... |
1091 |
int ret = 0; /* return value */ |
74373c6ac [PATCH] bitmap: r... |
1092 |
|
3cf64b933 [PATCH] bitmap: r... |
1093 1094 1095 1096 1097 1098 1099 1100 1101 |
/* * Either nlongs_reg == 1 (for small orders that fit in one long) * or (offset == 0 && mask == ~0UL) (for larger multiword orders.) */ nbits_reg = 1 << order; index = pos / BITS_PER_LONG; offset = pos - (index * BITS_PER_LONG); nlongs_reg = BITS_TO_LONGS(nbits_reg); nbitsinlong = min(nbits_reg, BITS_PER_LONG); |
1da177e4c Linux-2.6.12-rc2 |
1102 |
|
3cf64b933 [PATCH] bitmap: r... |
1103 1104 1105 1106 |
/* * Can't do "mask = (1UL << nbitsinlong) - 1", as that * overflows if nbitsinlong == BITS_PER_LONG. */ |
74373c6ac [PATCH] bitmap: r... |
1107 |
mask = (1UL << (nbitsinlong - 1)); |
1da177e4c Linux-2.6.12-rc2 |
1108 |
mask += mask - 1; |
3cf64b933 [PATCH] bitmap: r... |
1109 |
mask <<= offset; |
1da177e4c Linux-2.6.12-rc2 |
1110 |
|
3cf64b933 [PATCH] bitmap: r... |
1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 |
switch (reg_op) { case REG_OP_ISFREE: for (i = 0; i < nlongs_reg; i++) { if (bitmap[index + i] & mask) goto done; } ret = 1; /* all bits in region free (zero) */ break; case REG_OP_ALLOC: for (i = 0; i < nlongs_reg; i++) bitmap[index + i] |= mask; break; case REG_OP_RELEASE: for (i = 0; i < nlongs_reg; i++) bitmap[index + i] &= ~mask; break; |
1da177e4c Linux-2.6.12-rc2 |
1129 |
} |
3cf64b933 [PATCH] bitmap: r... |
1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 |
done: return ret; } /** * bitmap_find_free_region - find a contiguous aligned mem region * @bitmap: array of unsigned longs corresponding to the bitmap * @bits: number of bits in the bitmap * @order: region size (log base 2 of number of bits) to find * * Find a region of free (zero) bits in a @bitmap of @bits bits and * allocate them (set them to one). Only consider regions of length * a power (@order) of two, aligned to that power of two, which * makes the search algorithm much faster. * * Return the bit offset in bitmap of the allocated region, * or -errno on failure. */ |
9279d3286 lib: bitmap: chan... |
1148 |
int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) |
3cf64b933 [PATCH] bitmap: r... |
1149 |
{ |
9279d3286 lib: bitmap: chan... |
1150 |
unsigned int pos, end; /* scans bitmap by regions of size order */ |
aa8e4fc68 bitmap: fix end c... |
1151 |
|
9279d3286 lib: bitmap: chan... |
1152 |
for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) { |
aa8e4fc68 bitmap: fix end c... |
1153 1154 1155 1156 1157 1158 |
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) continue; __reg_op(bitmap, pos, order, REG_OP_ALLOC); return pos; } return -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
1159 1160 1161 1162 |
} EXPORT_SYMBOL(bitmap_find_free_region); /** |
87e248025 [PATCH] bitmap: r... |
1163 |
* bitmap_release_region - release allocated bitmap region |
3cf64b933 [PATCH] bitmap: r... |
1164 1165 1166 |
* @bitmap: array of unsigned longs corresponding to the bitmap * @pos: beginning of bit region to release * @order: region size (log base 2 of number of bits) to release |
1da177e4c Linux-2.6.12-rc2 |
1167 |
* |
72fd4a35a [PATCH] Numerous ... |
1168 |
* This is the complement to __bitmap_find_free_region() and releases |
1da177e4c Linux-2.6.12-rc2 |
1169 |
* the found region (by clearing it in the bitmap). |
3cf64b933 [PATCH] bitmap: r... |
1170 1171 |
* * No return value. |
1da177e4c Linux-2.6.12-rc2 |
1172 |
*/ |
9279d3286 lib: bitmap: chan... |
1173 |
void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4c Linux-2.6.12-rc2 |
1174 |
{ |
3cf64b933 [PATCH] bitmap: r... |
1175 |
__reg_op(bitmap, pos, order, REG_OP_RELEASE); |
1da177e4c Linux-2.6.12-rc2 |
1176 1177 |
} EXPORT_SYMBOL(bitmap_release_region); |
87e248025 [PATCH] bitmap: r... |
1178 1179 |
/** * bitmap_allocate_region - allocate bitmap region |
3cf64b933 [PATCH] bitmap: r... |
1180 1181 1182 |
* @bitmap: array of unsigned longs corresponding to the bitmap * @pos: beginning of bit region to allocate * @order: region size (log base 2 of number of bits) to allocate |
87e248025 [PATCH] bitmap: r... |
1183 1184 |
* * Allocate (set bits in) a specified region of a bitmap. |
3cf64b933 [PATCH] bitmap: r... |
1185 |
* |
6e1907ffd [PATCH] kernel-do... |
1186 |
* Return 0 on success, or %-EBUSY if specified region wasn't |
87e248025 [PATCH] bitmap: r... |
1187 1188 |
* free (not all bits were zero). */ |
9279d3286 lib: bitmap: chan... |
1189 |
int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4c Linux-2.6.12-rc2 |
1190 |
{ |
3cf64b933 [PATCH] bitmap: r... |
1191 1192 |
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) return -EBUSY; |
2ac521d33 lib: bitmap: micr... |
1193 |
return __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
1da177e4c Linux-2.6.12-rc2 |
1194 1195 |
} EXPORT_SYMBOL(bitmap_allocate_region); |
ccbe329bc bitmap: add bitma... |
1196 1197 1198 1199 1200 1201 1202 1203 1204 |
/** * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. * @dst: destination buffer * @src: bitmap to copy * @nbits: number of bits in the bitmap * * Require nbits % BITS_PER_LONG == 0. */ |
e8f242783 lib/bitmap.c: eli... |
1205 |
#ifdef __BIG_ENDIAN |
9b6c2d2e2 lib/bitmap.c: cha... |
1206 |
void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) |
ccbe329bc bitmap: add bitma... |
1207 |
{ |
9b6c2d2e2 lib/bitmap.c: cha... |
1208 |
unsigned int i; |
ccbe329bc bitmap: add bitma... |
1209 1210 1211 |
for (i = 0; i < nbits/BITS_PER_LONG; i++) { if (BITS_PER_LONG == 64) |
9b6c2d2e2 lib/bitmap.c: cha... |
1212 |
dst[i] = cpu_to_le64(src[i]); |
ccbe329bc bitmap: add bitma... |
1213 |
else |
9b6c2d2e2 lib/bitmap.c: cha... |
1214 |
dst[i] = cpu_to_le32(src[i]); |
ccbe329bc bitmap: add bitma... |
1215 1216 1217 |
} } EXPORT_SYMBOL(bitmap_copy_le); |
e8f242783 lib/bitmap.c: eli... |
1218 |
#endif |
c724f1936 bitmap: new bitma... |
1219 |
|
c42b65e36 bitmap: Add bitma... |
1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 |
unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) { return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long), flags); } EXPORT_SYMBOL(bitmap_alloc); unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags) { return bitmap_alloc(nbits, flags | __GFP_ZERO); } EXPORT_SYMBOL(bitmap_zalloc); void bitmap_free(const unsigned long *bitmap) { kfree(bitmap); } EXPORT_SYMBOL(bitmap_free); |
c724f1936 bitmap: new bitma... |
1238 1239 1240 1241 1242 1243 1244 |
#if BITS_PER_LONG == 64 /** * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap * @bitmap: array of unsigned longs, the destination bitmap * @buf: array of u32 (in host byte order), the source bitmap * @nbits: number of bits in @bitmap */ |
ccf7a6d45 lib/bitmap.c: dro... |
1245 |
void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits) |
c724f1936 bitmap: new bitma... |
1246 1247 |
{ unsigned int i, halfwords; |
c724f1936 bitmap: new bitma... |
1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 |
halfwords = DIV_ROUND_UP(nbits, 32); for (i = 0; i < halfwords; i++) { bitmap[i/2] = (unsigned long) buf[i]; if (++i < halfwords) bitmap[i/2] |= ((unsigned long) buf[i]) << 32; } /* Clear tail bits in last word beyond nbits. */ if (nbits % BITS_PER_LONG) bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits); } EXPORT_SYMBOL(bitmap_from_arr32); /** * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits * @buf: array of u32 (in host byte order), the dest bitmap * @bitmap: array of unsigned longs, the source bitmap * @nbits: number of bits in @bitmap */ void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits) { unsigned int i, halfwords; |
c724f1936 bitmap: new bitma... |
1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 |
halfwords = DIV_ROUND_UP(nbits, 32); for (i = 0; i < halfwords; i++) { buf[i] = (u32) (bitmap[i/2] & UINT_MAX); if (++i < halfwords) buf[i] = (u32) (bitmap[i/2] >> 32); } /* Clear tail bits in last element of array beyond nbits. */ if (nbits % BITS_PER_LONG) buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31)); } EXPORT_SYMBOL(bitmap_to_arr32); #endif |