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#include <linux/kernel.h>

#include <linux/module.h>

/**

 * int_sqrt - rough approximation to sqrt

 * @x: integer of which to calculate the sqrt

 *

 * A very rough approximation to the sqrt() function.

 */

unsigned long int_sqrt(unsigned long x)

{

        unsigned long op, res, one;

        op = x;

        res = 0;

        one = 1UL << (BITS_PER_LONG - 2);

        while (one > op)

                one >>= 2;

        while (one != 0) {

                if (op >= res + one) {

                        op = op - (res + one);

                        res = res +  2 * one;

                }

                res /= 2;

                one /= 4;

        }

        return res;

}

EXPORT_SYMBOL(int_sqrt);