2cda2728aa
lcm() was defined to take integer-sized arguments. The supplied arguments are multiplied, however, causing us to overflow given sufficiently large input. That in turn led to incorrect optimal I/O size reporting in some cases (RAID over RAID). Switch lcm() over to unsigned long similar to gcd() and move the function from blk-settings.c to lib. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
16 lines
265 B
C
16 lines
265 B
C
#include <linux/kernel.h>
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#include <linux/gcd.h>
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#include <linux/module.h>
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/* Lowest common multiple */
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unsigned long lcm(unsigned long a, unsigned long b)
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{
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if (a && b)
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return (a * b) / gcd(a, b);
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else if (b)
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return b;
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return a;
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}
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EXPORT_SYMBOL_GPL(lcm);
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