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1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * Cryptographic API for the 842 software compression algorithm. 4 * 5 * Copyright (C) IBM Corporation, 2011-2015 6 * 7 * Original Authors: Robert Jennings <rcj@linux.vnet.ibm.com> 8 * Seth Jennings <sjenning@linux.vnet.ibm.com> 9 * 10 * Rewrite: Dan Streetman <ddstreet@ieee.org> 11 * 12 * This is the software implementation of compression and decompression using 13 * the 842 format. This uses the software 842 library at lib/842/ which is 14 * only a reference implementation, and is very, very slow as compared to other 15 * software compressors. You probably do not want to use this software 16 * compression. If you have access to the PowerPC 842 compression hardware, you 17 * want to use the 842 hardware compression interface, which is at: 18 * drivers/crypto/nx/nx-842-crypto.c 19 */ 20 21#include <crypto/internal/scompress.h> 22#include <linux/init.h> 23#include <linux/module.h> 24#include <linux/sw842.h> 25 26static void *crypto842_alloc_ctx(void) 27{ 28 void *ctx; 29 30 ctx = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL); 31 if (!ctx) 32 return ERR_PTR(-ENOMEM); 33 34 return ctx; 35} 36 37static void crypto842_free_ctx(void *ctx) 38{ 39 kfree(ctx); 40} 41 42static int crypto842_scompress(struct crypto_scomp *tfm, 43 const u8 *src, unsigned int slen, 44 u8 *dst, unsigned int *dlen, void *ctx) 45{ 46 return sw842_compress(src, slen, dst, dlen, ctx); 47} 48 49static int crypto842_sdecompress(struct crypto_scomp *tfm, 50 const u8 *src, unsigned int slen, 51 u8 *dst, unsigned int *dlen, void *ctx) 52{ 53 return sw842_decompress(src, slen, dst, dlen); 54} 55 56static struct scomp_alg scomp = { 57 .alloc_ctx = crypto842_alloc_ctx, 58 .free_ctx = crypto842_free_ctx, 59 .compress = crypto842_scompress, 60 .decompress = crypto842_sdecompress, 61 .base = { 62 .cra_name = "842", 63 .cra_driver_name = "842-scomp", 64 .cra_priority = 100, 65 .cra_module = THIS_MODULE, 66 } 67}; 68 69static int __init crypto842_mod_init(void) 70{ 71 return crypto_register_scomp(&scomp); 72} 73module_init(crypto842_mod_init); 74 75static void __exit crypto842_mod_exit(void) 76{ 77 crypto_unregister_scomp(&scomp); 78} 79module_exit(crypto842_mod_exit); 80 81MODULE_LICENSE("GPL"); 82MODULE_DESCRIPTION("842 Software Compression Algorithm"); 83MODULE_ALIAS_CRYPTO("842"); 84MODULE_ALIAS_CRYPTO("842-generic"); 85MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");