ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 12:43:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

lib: add rocksoft model crc64

Browse Source 
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>
This commit is contained in:
Keith Busch
2022-03-03 12:13:09 -08:00
committed by Jens Axboe
parent 7ee8809df9
commit cbc0a40e17
3 changed files with 70 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
lib/gen_crc64table.c
View File

@@ -17,10 +17,30 @@
#include <stdio.h>
#define CRC64_ECMA182_POLY 0x42F0E1EBA9EA3693ULL
#define CRC64_ROCKSOFT_POLY 0x9A6C9329AC4BC9B5ULL
static uint64_t crc64_table[256] = {0};
static uint64_t crc64_rocksoft_table[256] = {0};
static void generate_crc64_table(void)
static void generate_reflected_crc64_table(uint64_t table[256], uint64_t poly)
{
uint64_t i, j, c, crc;
for (i = 0; i < 256; i++) {
crc = 0ULL;
c = i;
for (j = 0; j < 8; j++) {
if ((crc ^ (c >> j)) & 1)
crc = (crc >> 1) ^ poly;
else
crc >>= 1;
}
table[i] = crc;
}
}
static void generate_crc64_table(uint64_t table[256], uint64_t poly)
{
uint64_t i, j, c, crc;
@@ -30,26 +50,22 @@ static void generate_crc64_table(void)
for (j = 0; j < 8; j++) {
if ((crc ^ c) & 0x8000000000000000ULL)
crc = (crc << 1) ^ CRC64_ECMA182_POLY;
crc = (crc << 1) ^ poly;
else
crc <<= 1;
c <<= 1;
}
crc64_table[i] = crc;
table[i] = crc;
}
}
static void print_crc64_table(void)
static void output_table(uint64_t table[256])
{
int i;
printf("/* this file is generated - do not edit */\n\n");
printf("#include <linux/types.h>\n");
printf("#include <linux/cache.h>\n\n");
printf("static const u64 ____cacheline_aligned crc64table[256] = {\n");
for (i = 0; i < 256; i++) {
printf("\t0x%016" PRIx64 "ULL", crc64_table[i]);
printf("\t0x%016" PRIx64 "ULL", table[i]);
if (i & 0x1)
printf(",\n");
else
@@ -58,9 +74,22 @@ static void print_crc64_table(void)
printf("};\n");
}
static void print_crc64_tables(void)
{
printf("/* this file is generated - do not edit */\n\n");
printf("#include <linux/types.h>\n");
printf("#include <linux/cache.h>\n\n");
printf("static const u64 ____cacheline_aligned crc64table[256] = {\n");
output_table(crc64_table);
printf("\nstatic const u64 ____cacheline_aligned crc64rocksofttable[256] = {\n");
output_table(crc64_rocksoft_table);
}
int main(int argc, char *argv[])
{
generate_crc64_table();
print_crc64_table();
generate_crc64_table(crc64_table, CRC64_ECMA182_POLY);
generate_reflected_crc64_table(crc64_rocksoft_table, CRC64_ROCKSOFT_POLY);
print_crc64_tables();
return 0;
}