aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/crypto/crct10dif-pclmul_glue.c
blob: 7845d7fd54c0aa56232ae6b17dd433e26c879bd4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
/*
 * Cryptographic API.
 *
 * T10 Data Integrity Field CRC16 Crypto Transform using PCLMULQDQ Instructions
 *
 * Copyright (C) 2013 Intel Corporation
 * Author: Tim Chen <tim.c.chen@linux.intel.com>
 *
 * 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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/crc-t10dif.h>
#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/i387.h>
#include <asm/cpufeature.h>
#include <asm/cpu_device_id.h>

asmlinkage __u16 crc_t10dif_pcl(__u16 crc, const unsigned char *buf,
				size_t len);

struct chksum_desc_ctx {
	__u16 crc;
};

/*
 * Steps through buffer one byte at at time, calculates reflected
 * crc using table.
 */

static int chksum_init(struct shash_desc *desc)
{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	ctx->crc = 0;

	return 0;
}

static int chksum_update(struct shash_desc *desc, const u8 *data,
			 unsigned int length)
{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	if (irq_fpu_usable()) {
		kernel_fpu_begin();
		ctx->crc = crc_t10dif_pcl(ctx->crc, data, length);
		kernel_fpu_end();
	} else
		ctx->crc = crc_t10dif_generic(ctx->crc, data, length);
	return 0;
}

static int chksum_final(struct shash_desc *desc, u8 *out)
{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	*(__u16 *)out = ctx->crc;
	return 0;
}

static int __chksum_finup(__u16 *crcp, const u8 *data, unsigned int len,
			u8 *out)
{
	if (irq_fpu_usable()) {
		kernel_fpu_begin();
		*(__u16 *)out = crc_t10dif_pcl(*crcp, data, len);
		kernel_fpu_end();
	} else
		*(__u16 *)out = crc_t10dif_generic(*crcp, data, len);
	return 0;
}

static int chksum_finup(struct shash_desc *desc, const u8 *data,
			unsigned int len, u8 *out)
{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	return __chksum_finup(&ctx->crc, data, len, out);
}

static int chksum_digest(struct shash_desc *desc, const u8 *data,
			 unsigned int length, u8 *out)
{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	return __chksum_finup(&ctx->crc, data, length, out);
}

static struct shash_alg alg = {
	.digestsize		=	CRC_T10DIF_DIGEST_SIZE,
	.init		=	chksum_init,
	.update		=	chksum_update,
	.final		=	chksum_final,
	.finup		=	chksum_finup,
	.digest		=	chksum_digest,
	.descsize		=	sizeof(struct chksum_desc_ctx),
	.base			=	{
		.cra_name		=	"crct10dif",
		.cra_driver_name	=	"crct10dif-pclmul",
		.cra_priority		=	200,
		.cra_blocksize		=	CRC_T10DIF_BLOCK_SIZE,
		.cra_module		=	THIS_MODULE,
	}
};

static const struct x86_cpu_id crct10dif_cpu_id[] = {
	X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ),
	{}
};
MODULE_DEVICE_TABLE(x86cpu, crct10dif_cpu_id);

static int __init crct10dif_intel_mod_init(void)
{
	if (!x86_match_cpu(crct10dif_cpu_id))
		return -ENODEV;

	return crypto_register_shash(&alg);
}

static void __exit crct10dif_intel_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}

module_init(crct10dif_intel_mod_init);
module_exit(crct10dif_intel_mod_fini);

MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>");
MODULE_DESCRIPTION("T10 DIF CRC calculation accelerated with PCLMULQDQ.");
MODULE_LICENSE("GPL");

MODULE_ALIAS("crct10dif");
MODULE_ALIAS("crct10dif-pclmul");