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diff --git a/lib/crc32.c b/lib/crc32.c
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-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Aug 8, 2011 Bob Pearson with help from Joakim Tjernlund and George Spelvin
- * cleaned up code to current version of sparse and added the slicing-by-8
- * algorithm to the closely similar existing slicing-by-4 algorithm.
- *
- * Oct 15, 2000 Matt Domsch <Matt_Domsch@dell.com>
- * Nicer crc32 functions/docs submitted by linux@horizon.com. Thanks!
- * Code was from the public domain, copyright abandoned. Code was
- * subsequently included in the kernel, thus was re-licensed under the
- * GNU GPL v2.
- *
- * Oct 12, 2000 Matt Domsch <Matt_Domsch@dell.com>
- * Same crc32 function was used in 5 other places in the kernel.
- * I made one version, and deleted the others.
- * There are various incantations of crc32(). Some use a seed of 0 or ~0.
- * Some xor at the end with ~0. The generic crc32() function takes
- * seed as an argument, and doesn't xor at the end. Then individual
- * users can do whatever they need.
- * drivers/net/smc9194.c uses seed ~0, doesn't xor with ~0.
- * fs/jffs2 uses seed 0, doesn't xor with ~0.
- * fs/partitions/efi.c uses seed ~0, xor's with ~0.
- */
-
-/* see: Documentation/staging/crc32.rst for a description of algorithms */
-
-#include <linux/crc32.h>
-#include <linux/crc32poly.h>
-#include <linux/module.h>
-#include <linux/types.h>
-
-#include "crc32table.h"
-
-MODULE_AUTHOR("Matt Domsch <Matt_Domsch@dell.com>");
-MODULE_DESCRIPTION("Various CRC32 calculations");
-MODULE_LICENSE("GPL");
-
-u32 crc32_le_base(u32 crc, const u8 *p, size_t len)
-{
- while (len--)
- crc = (crc >> 8) ^ crc32table_le[(crc & 255) ^ *p++];
- return crc;
-}
-EXPORT_SYMBOL(crc32_le_base);
-
-u32 crc32c_base(u32 crc, const u8 *p, size_t len)
-{
- while (len--)
- crc = (crc >> 8) ^ crc32ctable_le[(crc & 255) ^ *p++];
- return crc;
-}
-EXPORT_SYMBOL(crc32c_base);
-
-/*
- * This multiplies the polynomials x and y modulo the given modulus.
- * This follows the "little-endian" CRC convention that the lsbit
- * represents the highest power of x, and the msbit represents x^0.
- */
-static u32 gf2_multiply(u32 x, u32 y, u32 modulus)
-{
- u32 product = x & 1 ? y : 0;
- int i;
-
- for (i = 0; i < 31; i++) {
- product = (product >> 1) ^ (product & 1 ? modulus : 0);
- x >>= 1;
- product ^= x & 1 ? y : 0;
- }
-
- return product;
-}
-
-/**
- * crc32_generic_shift - Append @len 0 bytes to crc, in logarithmic time
- * @crc: The original little-endian CRC (i.e. lsbit is x^31 coefficient)
- * @len: The number of bytes. @crc is multiplied by x^(8*@len)
- * @polynomial: The modulus used to reduce the result to 32 bits.
- *
- * It's possible to parallelize CRC computations by computing a CRC
- * over separate ranges of a buffer, then summing them.
- * This shifts the given CRC by 8*len bits (i.e. produces the same effect
- * as appending len bytes of zero to the data), in time proportional
- * to log(len).
- */
-static u32 crc32_generic_shift(u32 crc, size_t len, u32 polynomial)
-{
- u32 power = polynomial; /* CRC of x^32 */
- int i;
-
- /* Shift up to 32 bits in the simple linear way */
- for (i = 0; i < 8 * (int)(len & 3); i++)
- crc = (crc >> 1) ^ (crc & 1 ? polynomial : 0);
-
- len >>= 2;
- if (!len)
- return crc;
-
- for (;;) {
- /* "power" is x^(2^i), modulo the polynomial */
- if (len & 1)
- crc = gf2_multiply(crc, power, polynomial);
-
- len >>= 1;
- if (!len)
- break;
-
- /* Square power, advancing to x^(2^(i+1)) */
- power = gf2_multiply(power, power, polynomial);
- }
-
- return crc;
-}
-
-u32 crc32_le_shift(u32 crc, size_t len)
-{
- return crc32_generic_shift(crc, len, CRC32_POLY_LE);
-}
-EXPORT_SYMBOL(crc32_le_shift);
-
-u32 crc32_be_base(u32 crc, const u8 *p, size_t len)
-{
- while (len--)
- crc = (crc << 8) ^ crc32table_be[(crc >> 24) ^ *p++];
- return crc;
-}
-EXPORT_SYMBOL(crc32_be_base);