forked from mirrors/linux
692a68ee9c
In tools/ directory, function bitmap_clear() is currently only used in object file tools/testing/radix-tree/xarray.o. But instead of keeping a bitmap.c with only bitmap_clear() definition in radix-tree's own directory, it would be more proper to put it in common directory lib/. Sync the kernel definition and link some related libs, no functional change is expected. Signed-off-by: Wei Yang <richard.weiyang@gmail.com> CC: Matthew Wilcox <willy@infradead.org> CC: Yury Norov <yury.norov@gmail.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
122 lines
2.9 KiB
C
122 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* From lib/bitmap.c
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* Helper functions for bitmap.h.
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*/
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#include <linux/bitmap.h>
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unsigned int __bitmap_weight(const unsigned long *bitmap, int bits)
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{
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unsigned int k, w = 0, lim = bits/BITS_PER_LONG;
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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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}
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void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
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const unsigned long *bitmap2, int bits)
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{
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int k;
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int nr = BITS_TO_LONGS(bits);
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for (k = 0; k < nr; k++)
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dst[k] = bitmap1[k] | bitmap2[k];
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}
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size_t bitmap_scnprintf(unsigned long *bitmap, unsigned int nbits,
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char *buf, size_t size)
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{
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/* current bit is 'cur', most recently seen range is [rbot, rtop] */
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unsigned int cur, rbot, rtop;
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bool first = true;
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size_t ret = 0;
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rbot = cur = find_first_bit(bitmap, nbits);
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while (cur < nbits) {
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rtop = cur;
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cur = find_next_bit(bitmap, nbits, cur + 1);
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if (cur < nbits && cur <= rtop + 1)
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continue;
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if (!first)
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ret += scnprintf(buf + ret, size - ret, ",");
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first = false;
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ret += scnprintf(buf + ret, size - ret, "%d", rbot);
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if (rbot < rtop)
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ret += scnprintf(buf + ret, size - ret, "-%d", rtop);
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rbot = cur;
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}
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return ret;
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}
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bool __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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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)
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result |= (dst[k] = bitmap1[k] & bitmap2[k] &
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BITMAP_LAST_WORD_MASK(bits));
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return result != 0;
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}
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bool __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)
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if (bitmap1[k] != bitmap2[k])
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return false;
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if (bits % BITS_PER_LONG)
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if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
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return false;
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return true;
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}
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bool __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)
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if (bitmap1[k] & bitmap2[k])
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return true;
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if (bits % BITS_PER_LONG)
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if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
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return true;
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return false;
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}
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void __bitmap_clear(unsigned long *map, unsigned int start, int len)
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{
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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);
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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;
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mask_to_clear = ~0UL;
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p++;
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}
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if (len) {
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mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
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*p &= ~mask_to_clear;
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}
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}
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