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
crypto842_alloc_ctx(void)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
crypto842_free_ctx(void * ctx)37 static void crypto842_free_ctx(void *ctx)
38 {
39 kfree(ctx);
40 }
41
crypto842_scompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)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
crypto842_sdecompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)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
crypto842_mod_init(void)69 static int __init crypto842_mod_init(void)
70 {
71 return crypto_register_scomp(&scomp);
72 }
73 module_init(crypto842_mod_init);
74
crypto842_mod_exit(void)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