This source file includes following definitions.
- int_sqrt
- int_sqrt64
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9 #include <linux/kernel.h>
10 #include <linux/export.h>
11 #include <linux/bitops.h>
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19 unsigned long int_sqrt(unsigned long x)
20 {
21 unsigned long b, m, y = 0;
22
23 if (x <= 1)
24 return x;
25
26 m = 1UL << (__fls(x) & ~1UL);
27 while (m != 0) {
28 b = y + m;
29 y >>= 1;
30
31 if (x >= b) {
32 x -= b;
33 y += m;
34 }
35 m >>= 2;
36 }
37
38 return y;
39 }
40 EXPORT_SYMBOL(int_sqrt);
41
42 #if BITS_PER_LONG < 64
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48 u32 int_sqrt64(u64 x)
49 {
50 u64 b, m, y = 0;
51
52 if (x <= ULONG_MAX)
53 return int_sqrt((unsigned long) x);
54
55 m = 1ULL << ((fls64(x) - 1) & ~1ULL);
56 while (m != 0) {
57 b = y + m;
58 y >>= 1;
59
60 if (x >= b) {
61 x -= b;
62 y += m;
63 }
64 m >>= 2;
65 }
66
67 return y;
68 }
69 EXPORT_SYMBOL(int_sqrt64);
70 #endif