mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	Drop the repeated word "the". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200823040430.25807-1-rdunlap@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			80 lines
		
	
	
	
		
			2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
	
		
			2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-or-later
 | 
						|
/* 
 | 
						|
 * CRC32C
 | 
						|
 *@Article{castagnoli-crc,
 | 
						|
 * author =       { Guy Castagnoli and Stefan Braeuer and Martin Herrman},
 | 
						|
 * title =        {{Optimization of Cyclic Redundancy-Check Codes with 24
 | 
						|
 *                 and 32 Parity Bits}},
 | 
						|
 * journal =      IEEE Transactions on Communication,
 | 
						|
 * year =         {1993},
 | 
						|
 * volume =       {41},
 | 
						|
 * number =       {6},
 | 
						|
 * pages =        {},
 | 
						|
 * month =        {June},
 | 
						|
 *}
 | 
						|
 * Used by the iSCSI driver, possibly others, and derived from
 | 
						|
 * the iscsi-crc.c module of the linux-iscsi driver at
 | 
						|
 * http://linux-iscsi.sourceforge.net.
 | 
						|
 *
 | 
						|
 * Following the example of lib/crc32, this function is intended to be
 | 
						|
 * flexible and useful for all users.  Modules that currently have their
 | 
						|
 * own crc32c, but hopefully may be able to use this one are:
 | 
						|
 *  net/sctp (please add all your doco to here if you change to
 | 
						|
 *            use this one!)
 | 
						|
 *  <endoflist>
 | 
						|
 *
 | 
						|
 * Copyright (c) 2004 Cisco Systems, Inc.
 | 
						|
 */
 | 
						|
 | 
						|
#include <crypto/hash.h>
 | 
						|
#include <linux/err.h>
 | 
						|
#include <linux/init.h>
 | 
						|
#include <linux/kernel.h>
 | 
						|
#include <linux/module.h>
 | 
						|
#include <linux/crc32c.h>
 | 
						|
 | 
						|
static struct crypto_shash *tfm;
 | 
						|
 | 
						|
u32 crc32c(u32 crc, const void *address, unsigned int length)
 | 
						|
{
 | 
						|
	SHASH_DESC_ON_STACK(shash, tfm);
 | 
						|
	u32 ret, *ctx = (u32 *)shash_desc_ctx(shash);
 | 
						|
	int err;
 | 
						|
 | 
						|
	shash->tfm = tfm;
 | 
						|
	*ctx = crc;
 | 
						|
 | 
						|
	err = crypto_shash_update(shash, address, length);
 | 
						|
	BUG_ON(err);
 | 
						|
 | 
						|
	ret = *ctx;
 | 
						|
	barrier_data(ctx);
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
EXPORT_SYMBOL(crc32c);
 | 
						|
 | 
						|
static int __init libcrc32c_mod_init(void)
 | 
						|
{
 | 
						|
	tfm = crypto_alloc_shash("crc32c", 0, 0);
 | 
						|
	return PTR_ERR_OR_ZERO(tfm);
 | 
						|
}
 | 
						|
 | 
						|
static void __exit libcrc32c_mod_fini(void)
 | 
						|
{
 | 
						|
	crypto_free_shash(tfm);
 | 
						|
}
 | 
						|
 | 
						|
const char *crc32c_impl(void)
 | 
						|
{
 | 
						|
	return crypto_shash_driver_name(tfm);
 | 
						|
}
 | 
						|
EXPORT_SYMBOL(crc32c_impl);
 | 
						|
 | 
						|
module_init(libcrc32c_mod_init);
 | 
						|
module_exit(libcrc32c_mod_fini);
 | 
						|
 | 
						|
MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
 | 
						|
MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations");
 | 
						|
MODULE_LICENSE("GPL");
 | 
						|
MODULE_SOFTDEP("pre: crc32c");
 |