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 26 static 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 37 static void crypto842_free_ctx(void *ctx) 38 { 39 kfree(ctx); 40 } 41 42 static 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 49 static 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 56 static 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 69 static int __init crypto842_mod_init(void) 70 { 71 return crypto_register_scomp(&scomp); 72 } 73 module_init(crypto842_mod_init); 74 75 static void __exit crypto842_mod_exit(void) 76 { 77 crypto_unregister_scomp(&scomp); 78 } 79 module_exit(crypto842_mod_exit); 80 81 MODULE_LICENSE("GPL"); 82 MODULE_DESCRIPTION("842 Software Compression Algorithm"); 83 MODULE_ALIAS_CRYPTO("842"); 84 MODULE_ALIAS_CRYPTO("842-generic"); 85 MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>"); 86