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lib/bitmap.c
36.3 KB
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/* * lib/bitmap.c * Helper functions for bitmap.h. * * This source code is licensed under the GNU General Public License, * Version 2. See the file COPYING for more details. */ |
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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> #include <linux/string.h> |
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#include <linux/uaccess.h> |
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#include <asm/page.h> |
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/* * bitmaps provide an array of bits, implemented using an an * 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. * * These operations actually hold to a slightly stronger rule: * if you don't input any bitmaps to these ops that have some * unused bits set, then they won't output any set unused bits * in output bitmaps. * * 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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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/BITS_PER_LONG; |
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for (k = 0; k < lim; ++k) dst[k] = ~src[k]; if (bits % BITS_PER_LONG) |
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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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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); 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; } } EXPORT_SYMBOL(bitmap_set); |
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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; } } EXPORT_SYMBOL(bitmap_clear); |
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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. */ #define CHUNKSZ 32 #define nbits_to_hold_value(val) fls(val) |
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#define BASEDEC 10 /* fancier cpuset lists input in decimal */ /** |
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* __bitmap_parse - convert an ASCII hex string into a bitmap. * @buf: pointer to buffer containing string. * @buflen: buffer size in bytes. If string is smaller than this |
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* then it must be terminated with a \0. |
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* @is_user: location of buffer, 0 indicates kernel space |
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* @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 |
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* than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value * then leading 0-bits are prepended. %-EINVAL is returned for illegal |
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* characters and for grouping errors such as "1,,5", ",44", "," and "". * Leading and trailing whitespace accepted, but not embedded whitespace. */ |
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int __bitmap_parse(const char *buf, unsigned int buflen, int is_user, unsigned long *maskp, int nmaskbits) |
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{ int c, old_c, totaldigits, ndigits, nchunks, nbits; u32 chunk; |
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const char __user __force *ubuf = (const char __user __force *)buf; |
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bitmap_zero(maskp, nmaskbits); nchunks = nbits = totaldigits = c = 0; do { |
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chunk = 0; ndigits = totaldigits; |
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/* Get the next chunk of the bitmap */ |
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while (buflen) { |
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old_c = c; |
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if (is_user) { if (__get_user(c, ubuf++)) return -EFAULT; } else c = *buf++; buflen--; |
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if (isspace(c)) continue; /* * If the last character was a space and the current * character isn't '\0', we've got embedded whitespace. * This is a no-no, so throw an error. */ if (totaldigits && c && isspace(old_c)) return -EINVAL; /* A '\0' or a ',' signal the end of the chunk */ if (c == '\0' || c == ',') break; if (!isxdigit(c)) return -EINVAL; /* * Make sure there are at least 4 free bits in 'chunk'. * If not, this hexdigit will overflow 'chunk', so * throw an error. */ if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1)) return -EOVERFLOW; |
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chunk = (chunk << 4) | hex_to_bin(c); |
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totaldigits++; |
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} |
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if (ndigits == totaldigits) |
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return -EINVAL; if (nchunks == 0 && chunk == 0) continue; __bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits); *maskp |= chunk; nchunks++; nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ; if (nbits > nmaskbits) return -EOVERFLOW; |
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} while (buflen && c == ','); |
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return 0; } |
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EXPORT_SYMBOL(__bitmap_parse); /** |
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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. * * Wrapper for __bitmap_parse(), providing it with user buffer. * * We cannot have this as an inline function in bitmap.h because it needs * linux/uaccess.h to get the access_ok() declaration and this causes * cyclic dependencies. */ int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { if (!access_ok(VERIFY_READ, ubuf, ulen)) return -EFAULT; |
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return __bitmap_parse((const char __force *)ubuf, ulen, 1, maskp, nmaskbits); |
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} EXPORT_SYMBOL(bitmap_parse_user); |
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|
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/** |
5aaba3631 cpumask: factor o... |
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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... |
452 453 454 455 |
* * It is assumed that @buf is a pointer into a PAGE_SIZE area and that * sufficient storage remains at @buf to accommodate the * bitmap_print_to_pagebuf() output. |
5aaba3631 cpumask: factor o... |
456 457 458 459 |
*/ int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, int nmaskbits) { |
9cf79d115 bitmap: remove ex... |
460 |
ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf; |
5aaba3631 cpumask: factor o... |
461 |
int n = 0; |
9cf79d115 bitmap: remove ex... |
462 463 464 465 466 |
if (len > 1) n = list ? scnprintf(buf, len, "%*pbl ", nmaskbits, maskp) : scnprintf(buf, len, "%*pb ", nmaskbits, maskp); |
5aaba3631 cpumask: factor o... |
467 468 469 470 471 |
return n; } EXPORT_SYMBOL(bitmap_print_to_pagebuf); /** |
4b060420a bitmap, irq: add ... |
472 |
* __bitmap_parselist - convert list format ASCII string to bitmap |
b0825ee3a lib/bitmap.c: fix... |
473 |
* @buf: read nul-terminated user string from this buffer |
4b060420a bitmap, irq: add ... |
474 475 476 |
* @buflen: buffer size in bytes. If string is smaller than this * then it must be terminated with a \0. * @is_user: location of buffer, 0 indicates kernel space |
6e1907ffd [PATCH] kernel-do... |
477 |
* @maskp: write resulting mask here |
1da177e4c Linux-2.6.12-rc2 |
478 479 480 481 482 483 |
* @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... |
484 485 486 487 488 |
* 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 |
489 |
* |
6e1907ffd [PATCH] kernel-do... |
490 491 492 493 494 |
* Returns 0 on success, -errno on invalid input strings. * Error values: * %-EINVAL: second number in range smaller than first * %-EINVAL: invalid character in string * %-ERANGE: bit number specified too large for mask |
1da177e4c Linux-2.6.12-rc2 |
495 |
*/ |
4b060420a bitmap, irq: add ... |
496 497 498 |
static int __bitmap_parselist(const char *buf, unsigned int buflen, int is_user, unsigned long *maskp, int nmaskbits) |
1da177e4c Linux-2.6.12-rc2 |
499 |
{ |
2d13e6ca4 lib/bitmap.c: enh... |
500 501 |
unsigned int a, b, old_a, old_b; unsigned int group_size, used_size; |
9bf98f168 lib/bitmap.c: bit... |
502 |
int c, old_c, totaldigits, ndigits; |
b9c321fd8 lib/bitmap.c: qui... |
503 |
const char __user __force *ubuf = (const char __user __force *)buf; |
2d13e6ca4 lib/bitmap.c: enh... |
504 |
int at_start, in_range, in_partial_range; |
1da177e4c Linux-2.6.12-rc2 |
505 |
|
4b060420a bitmap, irq: add ... |
506 |
totaldigits = c = 0; |
2d13e6ca4 lib/bitmap.c: enh... |
507 508 |
old_a = old_b = 0; group_size = used_size = 0; |
1da177e4c Linux-2.6.12-rc2 |
509 510 |
bitmap_zero(maskp, nmaskbits); do { |
2528a8b8f __bitmap_parselis... |
511 |
at_start = 1; |
4b060420a bitmap, irq: add ... |
512 |
in_range = 0; |
2d13e6ca4 lib/bitmap.c: enh... |
513 |
in_partial_range = 0; |
4b060420a bitmap, irq: add ... |
514 |
a = b = 0; |
9bf98f168 lib/bitmap.c: bit... |
515 |
ndigits = totaldigits; |
4b060420a bitmap, irq: add ... |
516 517 518 519 520 521 522 523 524 525 526 527 |
/* Get the next cpu# or a range of cpu#'s */ while (buflen) { old_c = c; if (is_user) { if (__get_user(c, ubuf++)) return -EFAULT; } else c = *buf++; buflen--; if (isspace(c)) continue; |
4b060420a bitmap, irq: add ... |
528 529 530 |
/* A '\0' or a ',' signal the end of a cpu# or range */ if (c == '\0' || c == ',') break; |
9bf98f168 lib/bitmap.c: bit... |
531 532 533 534 535 536 537 538 539 540 541 |
/* * whitespaces between digits are not allowed, * but it's ok if whitespaces are on head or tail. * when old_c is whilespace, * if totaldigits == ndigits, whitespace is on head. * if whitespace is on tail, it should not run here. * as c was ',' or '\0', * the last code line has broken the current loop. */ if ((totaldigits != ndigits) && isspace(old_c)) return -EINVAL; |
4b060420a bitmap, irq: add ... |
542 |
|
2d13e6ca4 lib/bitmap.c: enh... |
543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 |
if (c == '/') { used_size = a; at_start = 1; in_range = 0; a = b = 0; continue; } if (c == ':') { old_a = a; old_b = b; at_start = 1; in_range = 0; in_partial_range = 1; a = b = 0; continue; } |
4b060420a bitmap, irq: add ... |
560 |
if (c == '-') { |
2528a8b8f __bitmap_parselis... |
561 |
if (at_start || in_range) |
4b060420a bitmap, irq: add ... |
562 563 564 |
return -EINVAL; b = 0; in_range = 1; |
d9282cb66 lib/bitmap.c: fix... |
565 |
at_start = 1; |
4b060420a bitmap, irq: add ... |
566 567 568 569 |
continue; } if (!isdigit(c)) |
1da177e4c Linux-2.6.12-rc2 |
570 |
return -EINVAL; |
4b060420a bitmap, irq: add ... |
571 572 573 574 |
b = b * 10 + (c - '0'); if (!in_range) a = b; |
2528a8b8f __bitmap_parselis... |
575 |
at_start = 0; |
4b060420a bitmap, irq: add ... |
576 |
totaldigits++; |
1da177e4c Linux-2.6.12-rc2 |
577 |
} |
9bf98f168 lib/bitmap.c: bit... |
578 579 |
if (ndigits == totaldigits) continue; |
2d13e6ca4 lib/bitmap.c: enh... |
580 581 582 583 584 585 |
if (in_partial_range) { group_size = a; a = old_a; b = old_b; old_a = old_b = 0; } |
d9282cb66 lib/bitmap.c: fix... |
586 587 588 |
/* if no digit is after '-', it's wrong*/ if (at_start && in_range) return -EINVAL; |
2d13e6ca4 lib/bitmap.c: enh... |
589 |
if (!(a <= b) || !(used_size <= group_size)) |
1da177e4c Linux-2.6.12-rc2 |
590 591 592 |
return -EINVAL; if (b >= nmaskbits) return -ERANGE; |
9bf98f168 lib/bitmap.c: bit... |
593 |
while (a <= b) { |
2d13e6ca4 lib/bitmap.c: enh... |
594 595 596 597 598 599 600 601 602 603 |
if (in_partial_range) { static int pos_in_group = 1; if (pos_in_group <= used_size) set_bit(a, maskp); if (a == b || ++pos_in_group > group_size) pos_in_group = 1; } else set_bit(a, maskp); |
9bf98f168 lib/bitmap.c: bit... |
604 |
a++; |
1da177e4c Linux-2.6.12-rc2 |
605 |
} |
4b060420a bitmap, irq: add ... |
606 |
} while (buflen && c == ','); |
1da177e4c Linux-2.6.12-rc2 |
607 608 |
return 0; } |
4b060420a bitmap, irq: add ... |
609 610 611 |
int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits) { |
bc5be1828 lib: bitmap: simp... |
612 613 614 |
char *nl = strchrnul(bp, ' '); int len = nl - bp; |
4b060420a bitmap, irq: add ... |
615 616 617 |
return __bitmap_parselist(bp, len, 0, maskp, nmaskbits); } |
1da177e4c Linux-2.6.12-rc2 |
618 |
EXPORT_SYMBOL(bitmap_parselist); |
4b060420a bitmap, irq: add ... |
619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 |
/** * 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. * * We cannot have this as an inline function in bitmap.h because it needs * linux/uaccess.h to get the access_ok() declaration and this causes * cyclic dependencies. */ int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { if (!access_ok(VERIFY_READ, ubuf, ulen)) return -EFAULT; |
b9c321fd8 lib/bitmap.c: qui... |
641 |
return __bitmap_parselist((const char __force *)ubuf, |
4b060420a bitmap, irq: add ... |
642 643 644 |
ulen, 1, maskp, nmaskbits); } EXPORT_SYMBOL(bitmap_parselist_user); |
72fd4a35a [PATCH] Numerous ... |
645 |
/** |
9a86e2bad lib: fix first li... |
646 |
* bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap |
fb5eeeee4 [PATCH] cpusets: ... |
647 |
* @buf: pointer to a bitmap |
df1d80a9e lib/bitmap.c: sim... |
648 649 |
* @pos: a bit position in @buf (0 <= @pos < @nbits) * @nbits: number of valid bit positions in @buf |
fb5eeeee4 [PATCH] cpusets: ... |
650 |
* |
df1d80a9e lib/bitmap.c: sim... |
651 |
* Map the bit at position @pos in @buf (of length @nbits) to the |
fb5eeeee4 [PATCH] cpusets: ... |
652 |
* ordinal of which set bit it is. If it is not set or if @pos |
96b7f3414 [PATCH] cpuset: b... |
653 |
* is not a valid bit position, map to -1. |
fb5eeeee4 [PATCH] cpusets: ... |
654 655 656 |
* * 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 ... |
657 |
* and other @pos values will get mapped to -1. When @pos value 7 |
fb5eeeee4 [PATCH] cpusets: ... |
658 659 660 661 662 |
* 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... |
663 |
static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits) |
fb5eeeee4 [PATCH] cpusets: ... |
664 |
{ |
df1d80a9e lib/bitmap.c: sim... |
665 |
if (pos >= nbits || !test_bit(pos, buf)) |
96b7f3414 [PATCH] cpuset: b... |
666 |
return -1; |
fb5eeeee4 [PATCH] cpusets: ... |
667 |
|
df1d80a9e lib/bitmap.c: sim... |
668 |
return __bitmap_weight(buf, pos); |
fb5eeeee4 [PATCH] cpusets: ... |
669 670 671 |
} /** |
9a86e2bad lib: fix first li... |
672 |
* bitmap_ord_to_pos - find position of n-th set bit in bitmap |
fb5eeeee4 [PATCH] cpusets: ... |
673 674 |
* @buf: pointer to bitmap * @ord: ordinal bit position (n-th set bit, n >= 0) |
f6a1f5db8 lib/bitmap.c: sim... |
675 |
* @nbits: number of valid bit positions in @buf |
fb5eeeee4 [PATCH] cpusets: ... |
676 677 |
* * Map the ordinal offset of bit @ord in @buf to its position in @buf. |
f6a1f5db8 lib/bitmap.c: sim... |
678 679 |
* Value of @ord should be in range 0 <= @ord < weight(buf). If @ord * >= weight(buf), returns @nbits. |
fb5eeeee4 [PATCH] cpusets: ... |
680 681 682 |
* * 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... |
683 |
* and all other @ord values returns @nbits. When @ord value 3 |
fb5eeeee4 [PATCH] cpusets: ... |
684 685 686 |
* 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... |
687 |
* The bit positions 0 through @nbits-1 are valid positions in @buf. |
fb5eeeee4 [PATCH] cpusets: ... |
688 |
*/ |
f6a1f5db8 lib/bitmap.c: sim... |
689 |
unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits) |
fb5eeeee4 [PATCH] cpusets: ... |
690 |
{ |
f6a1f5db8 lib/bitmap.c: sim... |
691 |
unsigned int pos; |
fb5eeeee4 [PATCH] cpusets: ... |
692 |
|
f6a1f5db8 lib/bitmap.c: sim... |
693 694 695 696 |
for (pos = find_first_bit(buf, nbits); pos < nbits && ord; pos = find_next_bit(buf, nbits, pos + 1)) ord--; |
fb5eeeee4 [PATCH] cpusets: ... |
697 698 699 700 701 702 |
return pos; } /** * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap |
fb5eeeee4 [PATCH] cpusets: ... |
703 |
* @dst: remapped result |
96b7f3414 [PATCH] cpuset: b... |
704 |
* @src: subset to be remapped |
fb5eeeee4 [PATCH] cpusets: ... |
705 706 |
* @old: defines domain of map * @new: defines range of map |
9814ec135 lib/bitmap.c: mak... |
707 |
* @nbits: number of bits in each of these bitmaps |
fb5eeeee4 [PATCH] cpusets: ... |
708 709 710 711 712 713 714 715 |
* * 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... |
716 717 718 |
* 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: ... |
719 |
* |
96b7f3414 [PATCH] cpuset: b... |
720 721 |
* The positions of unset bits in @old are mapped to themselves * (the identify map). |
fb5eeeee4 [PATCH] cpusets: ... |
722 723 724 725 |
* * Apply the above specified mapping to @src, placing the result in * @dst, clearing any bits previously set in @dst. * |
fb5eeeee4 [PATCH] cpusets: ... |
726 727 728 |
* 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... |
729 730 731 |
* 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: ... |
732 733 734 |
*/ void bitmap_remap(unsigned long *dst, const unsigned long *src, const unsigned long *old, const unsigned long *new, |
9814ec135 lib/bitmap.c: mak... |
735 |
unsigned int nbits) |
fb5eeeee4 [PATCH] cpusets: ... |
736 |
{ |
9814ec135 lib/bitmap.c: mak... |
737 |
unsigned int oldbit, w; |
fb5eeeee4 [PATCH] cpusets: ... |
738 |
|
fb5eeeee4 [PATCH] cpusets: ... |
739 740 |
if (dst == src) /* following doesn't handle inplace remaps */ return; |
9814ec135 lib/bitmap.c: mak... |
741 |
bitmap_zero(dst, nbits); |
96b7f3414 [PATCH] cpuset: b... |
742 |
|
9814ec135 lib/bitmap.c: mak... |
743 744 745 |
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... |
746 |
|
96b7f3414 [PATCH] cpuset: b... |
747 748 749 |
if (n < 0 || w == 0) set_bit(oldbit, dst); /* identity map */ else |
9814ec135 lib/bitmap.c: mak... |
750 |
set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst); |
fb5eeeee4 [PATCH] cpusets: ... |
751 752 753 754 755 756 |
} } EXPORT_SYMBOL(bitmap_remap); /** * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit |
6e1907ffd [PATCH] kernel-do... |
757 758 759 760 |
* @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: ... |
761 762 763 764 765 766 767 768 |
* * 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... |
769 770 |
* The positions of unset bits in @old are mapped to themselves * (the identify map). |
fb5eeeee4 [PATCH] cpusets: ... |
771 772 773 774 775 776 777 |
* * 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... |
778 779 |
* bit positions unchanged. So if say @oldbit is 5, then this routine * returns 13. |
fb5eeeee4 [PATCH] cpusets: ... |
780 781 782 783 |
*/ int bitmap_bitremap(int oldbit, const unsigned long *old, const unsigned long *new, int bits) { |
96b7f3414 [PATCH] cpuset: b... |
784 785 786 787 788 789 |
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: ... |
790 791 |
} EXPORT_SYMBOL(bitmap_bitremap); |
7ea931c9f mempolicy: add bi... |
792 793 794 795 796 797 798 799 800 801 802 803 804 805 |
/** * 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... |
806 |
* using the map { <n, m> | the n-th bit of @relmap is the |
7ea931c9f mempolicy: add bi... |
807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 |
* 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... |
841 |
* @dst corresponding to whatever is the twelfth bit that is |
7ea931c9f mempolicy: add bi... |
842 843 844 845 846 847 848 849 850 851 852 853 |
* 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(): * Let's say @relmap has these ten bits set: * 40 41 42 43 45 48 53 61 74 95 * (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 |
da3dae54e Documentation: Do... |
854 |
* avoid the possibility of an empty @dst result: |
7ea931c9f mempolicy: add bi... |
855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 |
* * 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 * (the weight of @relmap). * * @orig tmp @dst * 0 0 40 * 1 1 41 * 9 9 95 * 10 0 40 (*) * 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 * 78 102 211 1 2 8 41 42 74 (*) * * (*) For these marked lines, if we hadn't first done bitmap_fold() * 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... |
893 |
const unsigned long *relmap, unsigned int bits) |
7ea931c9f mempolicy: add bi... |
894 |
{ |
eb5698837 lib/bitmap.c: upd... |
895 |
unsigned int n, m; /* same meaning as in above comment */ |
7ea931c9f mempolicy: add bi... |
896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 |
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... |
912 |
for_each_set_bit(n, relmap, bits) { |
7ea931c9f mempolicy: add bi... |
913 914 915 916 917 918 919 920 921 922 923 924 925 |
/* m == bitmap_pos_to_ord(relmap, n, bits) */ if (test_bit(m, orig)) set_bit(n, dst); m++; } } EXPORT_SYMBOL(bitmap_onto); /** * 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... |
926 |
* @nbits: number of bits in each of these bitmaps |
7ea931c9f mempolicy: add bi... |
927 928 929 930 931 932 |
* * 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... |
933 |
unsigned int sz, unsigned int nbits) |
7ea931c9f mempolicy: add bi... |
934 |
{ |
b26ad5836 lib/bitmap.c: cha... |
935 |
unsigned int oldbit; |
7ea931c9f mempolicy: add bi... |
936 937 938 |
if (dst == orig) /* following doesn't handle inplace mappings */ return; |
b26ad5836 lib/bitmap.c: cha... |
939 |
bitmap_zero(dst, nbits); |
7ea931c9f mempolicy: add bi... |
940 |
|
b26ad5836 lib/bitmap.c: cha... |
941 |
for_each_set_bit(oldbit, orig, nbits) |
7ea931c9f mempolicy: add bi... |
942 943 944 |
set_bit(oldbit % sz, dst); } EXPORT_SYMBOL(bitmap_fold); |
3cf64b933 [PATCH] bitmap: r... |
945 946 947 948 949 950 |
/* * 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 |
951 |
* |
3cf64b933 [PATCH] bitmap: r... |
952 953 |
* 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 |
954 |
* |
3cf64b933 [PATCH] bitmap: r... |
955 956 957 958 959 960 |
* 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 |
961 |
*/ |
3cf64b933 [PATCH] bitmap: r... |
962 963 964 965 966 967 |
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... |
968 |
static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op) |
1da177e4c Linux-2.6.12-rc2 |
969 |
{ |
3cf64b933 [PATCH] bitmap: r... |
970 971 972 973 |
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... |
974 |
int nbitsinlong; /* num bits of region in each spanned long */ |
3cf64b933 [PATCH] bitmap: r... |
975 |
unsigned long mask; /* bitmask for one long of region */ |
74373c6ac [PATCH] bitmap: r... |
976 |
int i; /* scans bitmap by longs */ |
3cf64b933 [PATCH] bitmap: r... |
977 |
int ret = 0; /* return value */ |
74373c6ac [PATCH] bitmap: r... |
978 |
|
3cf64b933 [PATCH] bitmap: r... |
979 980 981 982 983 984 985 986 987 |
/* * 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 |
988 |
|
3cf64b933 [PATCH] bitmap: r... |
989 990 991 992 |
/* * Can't do "mask = (1UL << nbitsinlong) - 1", as that * overflows if nbitsinlong == BITS_PER_LONG. */ |
74373c6ac [PATCH] bitmap: r... |
993 |
mask = (1UL << (nbitsinlong - 1)); |
1da177e4c Linux-2.6.12-rc2 |
994 |
mask += mask - 1; |
3cf64b933 [PATCH] bitmap: r... |
995 |
mask <<= offset; |
1da177e4c Linux-2.6.12-rc2 |
996 |
|
3cf64b933 [PATCH] bitmap: r... |
997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 |
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 |
1015 |
} |
3cf64b933 [PATCH] bitmap: r... |
1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 |
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... |
1034 |
int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) |
3cf64b933 [PATCH] bitmap: r... |
1035 |
{ |
9279d3286 lib: bitmap: chan... |
1036 |
unsigned int pos, end; /* scans bitmap by regions of size order */ |
aa8e4fc68 bitmap: fix end c... |
1037 |
|
9279d3286 lib: bitmap: chan... |
1038 |
for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) { |
aa8e4fc68 bitmap: fix end c... |
1039 1040 1041 1042 1043 1044 |
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 |
1045 1046 1047 1048 |
} EXPORT_SYMBOL(bitmap_find_free_region); /** |
87e248025 [PATCH] bitmap: r... |
1049 |
* bitmap_release_region - release allocated bitmap region |
3cf64b933 [PATCH] bitmap: r... |
1050 1051 1052 |
* @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 |
1053 |
* |
72fd4a35a [PATCH] Numerous ... |
1054 |
* This is the complement to __bitmap_find_free_region() and releases |
1da177e4c Linux-2.6.12-rc2 |
1055 |
* the found region (by clearing it in the bitmap). |
3cf64b933 [PATCH] bitmap: r... |
1056 1057 |
* * No return value. |
1da177e4c Linux-2.6.12-rc2 |
1058 |
*/ |
9279d3286 lib: bitmap: chan... |
1059 |
void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4c Linux-2.6.12-rc2 |
1060 |
{ |
3cf64b933 [PATCH] bitmap: r... |
1061 |
__reg_op(bitmap, pos, order, REG_OP_RELEASE); |
1da177e4c Linux-2.6.12-rc2 |
1062 1063 |
} EXPORT_SYMBOL(bitmap_release_region); |
87e248025 [PATCH] bitmap: r... |
1064 1065 |
/** * bitmap_allocate_region - allocate bitmap region |
3cf64b933 [PATCH] bitmap: r... |
1066 1067 1068 |
* @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... |
1069 1070 |
* * Allocate (set bits in) a specified region of a bitmap. |
3cf64b933 [PATCH] bitmap: r... |
1071 |
* |
6e1907ffd [PATCH] kernel-do... |
1072 |
* Return 0 on success, or %-EBUSY if specified region wasn't |
87e248025 [PATCH] bitmap: r... |
1073 1074 |
* free (not all bits were zero). */ |
9279d3286 lib: bitmap: chan... |
1075 |
int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4c Linux-2.6.12-rc2 |
1076 |
{ |
3cf64b933 [PATCH] bitmap: r... |
1077 1078 |
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) return -EBUSY; |
2ac521d33 lib: bitmap: micr... |
1079 |
return __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
1da177e4c Linux-2.6.12-rc2 |
1080 1081 |
} EXPORT_SYMBOL(bitmap_allocate_region); |
ccbe329bc bitmap: add bitma... |
1082 1083 |
/** |
e52bc7c28 lib/bitmap.c: con... |
1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 |
* bitmap_from_u32array - copy the contents of a u32 array of bits to bitmap * @bitmap: array of unsigned longs, the destination bitmap, non NULL * @nbits: number of bits in @bitmap * @buf: array of u32 (in host byte order), the source bitmap, non NULL * @nwords: number of u32 words in @buf * * copy min(nbits, 32*nwords) bits from @buf to @bitmap, remaining * bits between nword and nbits in @bitmap (if any) are cleared. In * last word of @bitmap, the bits beyond nbits (if any) are kept * unchanged. * * Return the number of bits effectively copied. */ unsigned int bitmap_from_u32array(unsigned long *bitmap, unsigned int nbits, const u32 *buf, unsigned int nwords) { unsigned int dst_idx, src_idx; for (src_idx = dst_idx = 0; dst_idx < BITS_TO_LONGS(nbits); ++dst_idx) { unsigned long part = 0; if (src_idx < nwords) part = buf[src_idx++]; #if BITS_PER_LONG == 64 if (src_idx < nwords) part |= ((unsigned long) buf[src_idx++]) << 32; #endif if (dst_idx < nbits/BITS_PER_LONG) bitmap[dst_idx] = part; else { unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); bitmap[dst_idx] = (bitmap[dst_idx] & ~mask) | (part & mask); } } return min_t(unsigned int, nbits, 32*nwords); } EXPORT_SYMBOL(bitmap_from_u32array); /** * bitmap_to_u32array - copy the contents of bitmap to a u32 array of bits * @buf: array of u32 (in host byte order), the dest bitmap, non NULL * @nwords: number of u32 words in @buf * @bitmap: array of unsigned longs, the source bitmap, non NULL * @nbits: number of bits in @bitmap * * copy min(nbits, 32*nwords) bits from @bitmap to @buf. Remaining * bits after nbits in @buf (if any) are cleared. * * Return the number of bits effectively copied. */ unsigned int bitmap_to_u32array(u32 *buf, unsigned int nwords, const unsigned long *bitmap, unsigned int nbits) { unsigned int dst_idx = 0, src_idx = 0; while (dst_idx < nwords) { unsigned long part = 0; if (src_idx < BITS_TO_LONGS(nbits)) { part = bitmap[src_idx]; if (src_idx >= nbits/BITS_PER_LONG) part &= BITMAP_LAST_WORD_MASK(nbits); src_idx++; } buf[dst_idx++] = part & 0xffffffffUL; #if BITS_PER_LONG == 64 if (dst_idx < nwords) { part >>= 32; buf[dst_idx++] = part & 0xffffffffUL; } #endif } return min_t(unsigned int, nbits, 32*nwords); } EXPORT_SYMBOL(bitmap_to_u32array); /** |
ccbe329bc bitmap: add bitma... |
1171 1172 1173 1174 1175 1176 1177 |
* 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... |
1178 |
#ifdef __BIG_ENDIAN |
9b6c2d2e2 lib/bitmap.c: cha... |
1179 |
void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) |
ccbe329bc bitmap: add bitma... |
1180 |
{ |
9b6c2d2e2 lib/bitmap.c: cha... |
1181 |
unsigned int i; |
ccbe329bc bitmap: add bitma... |
1182 1183 1184 |
for (i = 0; i < nbits/BITS_PER_LONG; i++) { if (BITS_PER_LONG == 64) |
9b6c2d2e2 lib/bitmap.c: cha... |
1185 |
dst[i] = cpu_to_le64(src[i]); |
ccbe329bc bitmap: add bitma... |
1186 |
else |
9b6c2d2e2 lib/bitmap.c: cha... |
1187 |
dst[i] = cpu_to_le32(src[i]); |
ccbe329bc bitmap: add bitma... |
1188 1189 1190 |
} } EXPORT_SYMBOL(bitmap_copy_le); |
e8f242783 lib/bitmap.c: eli... |
1191 |
#endif |