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 struct crypto842_ctx { 27 void *wmem; /* working memory for compress */ 28 }; 29 30 static void *crypto842_alloc_ctx(void) 31 { 32 void *ctx; 33 34 ctx = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL); 35 if (!ctx) 36 return ERR_PTR(-ENOMEM); 37 38 return ctx; 39 } 40 41 static void crypto842_free_ctx(void *ctx) 42 { 43 kfree(ctx); 44 } 45 46 static int crypto842_scompress(struct crypto_scomp *tfm, 47 const u8 *src, unsigned int slen, 48 u8 *dst, unsigned int *dlen, void *ctx) 49 { 50 return sw842_compress(src, slen, dst, dlen, ctx); 51 } 52 53 static int crypto842_sdecompress(struct crypto_scomp *tfm, 54 const u8 *src, unsigned int slen, 55 u8 *dst, unsigned int *dlen, void *ctx) 56 { 57 return sw842_decompress(src, slen, dst, dlen); 58 } 59 60 static struct scomp_alg scomp = { 61 .alloc_ctx = crypto842_alloc_ctx, 62 .free_ctx = crypto842_free_ctx, 63 .compress = crypto842_scompress, 64 .decompress = crypto842_sdecompress, 65 .base = { 66 .cra_name = "842", 67 .cra_driver_name = "842-scomp", 68 .cra_priority = 100, 69 .cra_module = THIS_MODULE, 70 } 71 }; 72 73 static int __init crypto842_mod_init(void) 74 { 75 return crypto_register_scomp(&scomp); 76 } 77 subsys_initcall(crypto842_mod_init); 78 79 static void __exit crypto842_mod_exit(void) 80 { 81 crypto_unregister_scomp(&scomp); 82 } 83 module_exit(crypto842_mod_exit); 84 85 MODULE_LICENSE("GPL"); 86 MODULE_DESCRIPTION("842 Software Compression Algorithm"); 87 MODULE_ALIAS_CRYPTO("842"); 88 MODULE_ALIAS_CRYPTO("842-generic"); 89 MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>"); 90