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#ifndef mul_u64_u64_shr

static inline u64 mul_u64_u64_shr(u64 a, u64 mul, unsigned int shift)

{

	return (u64)(((unsigned __int128)a * mul) >> shift);

}

#endif /* mul_u64_u64_shr */

#endif /* mul_u64_u32_shr */

#ifndef mul_u64_u64_shr

static inline u64 mul_u64_u64_shr(u64 a, u64 b, unsigned int shift)

{

	union {

		u64 ll;

		struct {

#ifdef __BIG_ENDIAN

			u32 high, low;

#else

			u32 low, high;

#endif

		} l;

	} rl, rm, rn, rh, a0, b0;

	u64 c;

	a0.ll = a;

	b0.ll = b;

	rl.ll = (u64)a0.l.low * b0.l.low;

	rm.ll = (u64)a0.l.low * b0.l.high;

	rn.ll = (u64)a0.l.high * b0.l.low;

	rh.ll = (u64)a0.l.high * b0.l.high;

	/*

	 * Each of these lines computes a 64-bit intermediate result into "c",

	 * starting at bits 32-95.  The low 32-bits go into the result of the

	 * multiplication, the high 32-bits are carried into the next step.

	 */

	rl.l.high = c = (u64)rl.l.high + rm.l.low + rn.l.low;

	rh.l.low = c = (c >> 32) + rm.l.high + rn.l.high + rh.l.low;

	rh.l.high = (c >> 32) + rh.l.high;

	/*

	 * The 128-bit result of the multiplication is in rl.ll and rh.ll,

	 * shift it right and throw away the high part of the result.

	 */

	if (shift == 0)

		return rl.ll;

	if (shift < 64)

		return (rl.ll >> shift) | (rh.ll << (64 - shift));

	return rh.ll >> (shift & 63);

}

#endif

#ifndef mul_u64_u32_div

static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 divisor)

{

	union {

		u64 ll;

		struct {

#ifdef __BIG_ENDIAN

			u32 high, low;

#else

			u32 low, high;

#endif

		} l;

	} u, rl, rh;

	u.ll = a;

	rl.ll = (u64)u.l.low * mul;

	rh.ll = (u64)u.l.high * mul + rl.l.high;

	/* Bits 32-63 of the result will be in rh.l.low. */

	rl.l.high = do_div(rh.ll, divisor);

	/* Bits 0-31 of the result will be in rl.l.low.	*/

	do_div(rl.ll, divisor);

	rl.l.high = rh.l.low;

	return rl.ll;