https://github.com/torvalds/linux
Tip revision: 1a695a905c18548062509178b98bc91e67510864 authored by Linus Torvalds on 29 May 2016, 16:29:24 UTC
Linux 4.7-rc1
Linux 4.7-rc1
Tip revision: 1a695a9
842.c
/*
* Cryptographic API for the 842 software compression algorithm.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Copyright (C) IBM Corporation, 2011-2015
*
* Original Authors: Robert Jennings <rcj@linux.vnet.ibm.com>
* Seth Jennings <sjenning@linux.vnet.ibm.com>
*
* Rewrite: Dan Streetman <ddstreet@ieee.org>
*
* This is the software implementation of compression and decompression using
* the 842 format. This uses the software 842 library at lib/842/ which is
* only a reference implementation, and is very, very slow as compared to other
* software compressors. You probably do not want to use this software
* compression. If you have access to the PowerPC 842 compression hardware, you
* want to use the 842 hardware compression interface, which is at:
* drivers/crypto/nx/nx-842-crypto.c
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/crypto.h>
#include <linux/sw842.h>
struct crypto842_ctx {
char wmem[SW842_MEM_COMPRESS]; /* working memory for compress */
};
static int crypto842_compress(struct crypto_tfm *tfm,
const u8 *src, unsigned int slen,
u8 *dst, unsigned int *dlen)
{
struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm);
return sw842_compress(src, slen, dst, dlen, ctx->wmem);
}
static int crypto842_decompress(struct crypto_tfm *tfm,
const u8 *src, unsigned int slen,
u8 *dst, unsigned int *dlen)
{
return sw842_decompress(src, slen, dst, dlen);
}
static struct crypto_alg alg = {
.cra_name = "842",
.cra_driver_name = "842-generic",
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
.cra_ctxsize = sizeof(struct crypto842_ctx),
.cra_module = THIS_MODULE,
.cra_u = { .compress = {
.coa_compress = crypto842_compress,
.coa_decompress = crypto842_decompress } }
};
static int __init crypto842_mod_init(void)
{
return crypto_register_alg(&alg);
}
module_init(crypto842_mod_init);
static void __exit crypto842_mod_exit(void)
{
crypto_unregister_alg(&alg);
}
module_exit(crypto842_mod_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("842 Software Compression Algorithm");
MODULE_ALIAS_CRYPTO("842");
MODULE_ALIAS_CRYPTO("842-generic");
MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");