mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-17 01:34:00 +08:00
cbc0a40e17
The NVM Express specification extended data integrity fields to 64 bits
using the Rocksoft parameters. Add the poly to the crc64 table
generation, and provide a generic library routine implementing the
algorithm.
The Rocksoft 64-bit CRC model parameters are as follows:
Poly: 0xAD93D23594C93659
Initial value: 0xFFFFFFFFFFFFFFFF
Reflected Input: True
Reflected Output: True
Xor Final: 0xFFFFFFFFFFFFFFFF
Since this model used reflected bits, the implementation generates the
reflected table so the result is ordered consistently.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220303201312.3255347-6-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
86 lines
2.6 KiB
C
86 lines
2.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Normal 64-bit CRC calculation.
|
|
*
|
|
* This is a basic crc64 implementation following ECMA-182 specification,
|
|
* which can be found from,
|
|
* https://www.ecma-international.org/publications/standards/Ecma-182.htm
|
|
*
|
|
* Dr. Ross N. Williams has a great document to introduce the idea of CRC
|
|
* algorithm, here the CRC64 code is also inspired by the table-driven
|
|
* algorithm and detail example from this paper. This paper can be found
|
|
* from,
|
|
* http://www.ross.net/crc/download/crc_v3.txt
|
|
*
|
|
* crc64table[256] is the lookup table of a table-driven 64-bit CRC
|
|
* calculation, which is generated by gen_crc64table.c in kernel build
|
|
* time. The polynomial of crc64 arithmetic is from ECMA-182 specification
|
|
* as well, which is defined as,
|
|
*
|
|
* x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 +
|
|
* x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 +
|
|
* x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
|
|
* x^7 + x^4 + x + 1
|
|
*
|
|
* crc64rocksoft[256] table is from the Rocksoft specification polynomial
|
|
* defined as,
|
|
*
|
|
* x^64 + x^63 + x^61 + x^59 + x^58 + x^56 + x^55 + x^52 + x^49 + x^48 + x^47 +
|
|
* x^46 + x^44 + x^41 + x^37 + x^36 + x^34 + x^32 + x^31 + x^28 + x^26 + x^23 +
|
|
* x^22 + x^19 + x^16 + x^13 + x^12 + x^10 + x^9 + x^6 + x^4 + x^3 + 1
|
|
*
|
|
* Copyright 2018 SUSE Linux.
|
|
* Author: Coly Li <colyli@suse.de>
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/crc64.h>
|
|
#include "crc64table.h"
|
|
|
|
MODULE_DESCRIPTION("CRC64 calculations");
|
|
MODULE_LICENSE("GPL v2");
|
|
|
|
/**
|
|
* crc64_be - Calculate bitwise big-endian ECMA-182 CRC64
|
|
* @crc: seed value for computation. 0 or (u64)~0 for a new CRC calculation,
|
|
* or the previous crc64 value if computing incrementally.
|
|
* @p: pointer to buffer over which CRC64 is run
|
|
* @len: length of buffer @p
|
|
*/
|
|
u64 __pure crc64_be(u64 crc, const void *p, size_t len)
|
|
{
|
|
size_t i, t;
|
|
|
|
const unsigned char *_p = p;
|
|
|
|
for (i = 0; i < len; i++) {
|
|
t = ((crc >> 56) ^ (*_p++)) & 0xFF;
|
|
crc = crc64table[t] ^ (crc << 8);
|
|
}
|
|
|
|
return crc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(crc64_be);
|
|
|
|
/**
|
|
* crc64_rocksoft_generic - Calculate bitwise Rocksoft CRC64
|
|
* @crc: seed value for computation. 0 for a new CRC calculation, or the
|
|
* previous crc64 value if computing incrementally.
|
|
* @p: pointer to buffer over which CRC64 is run
|
|
* @len: length of buffer @p
|
|
*/
|
|
u64 __pure crc64_rocksoft_generic(u64 crc, const void *p, size_t len)
|
|
{
|
|
const unsigned char *_p = p;
|
|
size_t i;
|
|
|
|
crc = ~crc;
|
|
|
|
for (i = 0; i < len; i++)
|
|
crc = (crc >> 8) ^ crc64rocksofttable[(crc & 0xff) ^ *_p++];
|
|
|
|
return ~crc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(crc64_rocksoft_generic);
|