forked from mirrors/linux
		
	gen_crc64table requires linux include files to be installed in
/usr/include/linux.  This is a new requrement so hosts that could
previously build the kernel, now cannot.
gen_crc64table makes this requirement by including <linux/swab.h>, but
nothing from that header is actaully used.
So remove the #include, so that the linux headers no longer need to be
installed.
Fixes: feba04fd2c ("lib: add crc64 calculation routines")
Signed-off-by: NeilBrown <neil@brown.name>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
	
			
		
			
				
	
	
		
			66 lines
		
	
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
 | 
						|
/*
 | 
						|
 * Generate lookup table for the table-driven CRC64 calculation.
 | 
						|
 *
 | 
						|
 * gen_crc64table is executed in kernel build time and generates
 | 
						|
 * lib/crc64table.h. This header is included by lib/crc64.c for
 | 
						|
 * the table-driven CRC64 calculation.
 | 
						|
 *
 | 
						|
 * See lib/crc64.c for more information about which specification
 | 
						|
 * and polynomial arithmetic that gen_crc64table.c follows to
 | 
						|
 * generate the lookup table.
 | 
						|
 *
 | 
						|
 * Copyright 2018 SUSE Linux.
 | 
						|
 *   Author: Coly Li <colyli@suse.de>
 | 
						|
 */
 | 
						|
#include <inttypes.h>
 | 
						|
#include <stdio.h>
 | 
						|
 | 
						|
#define CRC64_ECMA182_POLY 0x42F0E1EBA9EA3693ULL
 | 
						|
 | 
						|
static uint64_t crc64_table[256] = {0};
 | 
						|
 | 
						|
static void generate_crc64_table(void)
 | 
						|
{
 | 
						|
	uint64_t i, j, c, crc;
 | 
						|
 | 
						|
	for (i = 0; i < 256; i++) {
 | 
						|
		crc = 0;
 | 
						|
		c = i << 56;
 | 
						|
 | 
						|
		for (j = 0; j < 8; j++) {
 | 
						|
			if ((crc ^ c) & 0x8000000000000000ULL)
 | 
						|
				crc = (crc << 1) ^ CRC64_ECMA182_POLY;
 | 
						|
			else
 | 
						|
				crc <<= 1;
 | 
						|
			c <<= 1;
 | 
						|
		}
 | 
						|
 | 
						|
		crc64_table[i] = crc;
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
static void print_crc64_table(void)
 | 
						|
{
 | 
						|
	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]);
 | 
						|
		if (i & 0x1)
 | 
						|
			printf(",\n");
 | 
						|
		else
 | 
						|
			printf(", ");
 | 
						|
	}
 | 
						|
	printf("};\n");
 | 
						|
}
 | 
						|
 | 
						|
int main(int argc, char *argv[])
 | 
						|
{
 | 
						|
	generate_crc64_table();
 | 
						|
	print_crc64_table();
 | 
						|
	return 0;
 | 
						|
}
 |