/*-
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 *
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 *       notice, this list of conditions and the following disclaimer.
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 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
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 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
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 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#include "spdk/crc16.h"

uint16_t
spdk_crc16_t10dif(const void *buf, size_t len)
{
	uint32_t j, rem = 0;
	const uint8_t *data = (const uint8_t *)buf;
	size_t i;

	uint16_t poly = SPDK_T10DIF_CRC16_POLYNOMIAL;

	for (i = 0; i < len; i++) {
		rem = rem ^ (data[i] << 8);
		for (j = 0; j < 8; j++) {
			rem = rem << 1;
			rem = (rem & 0x10000) ? rem ^ poly : rem;
		}
	}
	return (uint16_t)rem;
}