mirror of https://gitee.com/openkylin/linux.git
29 lines
563 B
C
29 lines
563 B
C
#include <linux/module.h>
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#include <linux/bitops.h>
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/* Find string of zero bits in a bitmap */
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unsigned long
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find_next_zero_string(unsigned long *bitmap, long start, long nbits, int len)
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{
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unsigned long n, end, i;
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again:
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n = find_next_zero_bit(bitmap, nbits, start);
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if (n == -1)
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return -1;
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/* could test bitsliced, but it's hardly worth it */
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end = n+len;
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if (end > nbits)
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return -1;
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for (i = n+1; i < end; i++) {
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if (test_bit(i, bitmap)) {
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start = i+1;
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goto again;
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}
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}
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return n;
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}
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EXPORT_SYMBOL(find_next_zero_string);
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