[deliverable/linux.git] / arch / x86 / crypto / crc32c-intel_glue.c

/*
 * Using hardware provided CRC32 instruction to accelerate the CRC32 disposal.
 * CRC32C polynomial:0x1EDC6F41(BE)/0x82F63B78(LE)
 * CRC32 is a new instruction in Intel SSE4.2, the reference can be found at:
 * http://www.intel.com/products/processor/manuals/
 * Intel(R) 64 and IA-32 Architectures Software Developer's Manual
 * Volume 2A: Instruction Set Reference, A-M
 *
 * Copyright (C) 2008 Intel Corporation
 * Authors: Austin Zhang <austin_zhang@linux.intel.com>
 *          Kent Liu <kent.liu@intel.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <crypto/internal/hash.h>

#include <asm/cpufeature.h>
#include <asm/cpu_device_id.h>

#define CHKSUM_BLOCK_SIZE	1
#define CHKSUM_DIGEST_SIZE	4

#define SCALE_F	sizeof(unsigned long)

#ifdef CONFIG_X86_64
#define REX_PRE "0x48, "
#else
#define REX_PRE
#endif

static u32 crc32c_intel_le_hw_byte(u32 crc, unsigned char const *data, size_t length)
{
	while (length--) {
		__asm__ __volatile__(
			".byte 0xf2, 0xf, 0x38, 0xf0, 0xf1"
			:"=S"(crc)
			:"0"(crc), "c"(*data)
		);
		data++;
	}

	return crc;
}

static u32 __pure crc32c_intel_le_hw(u32 crc, unsigned char const *p, size_t len)
{
	unsigned int iquotient = len / SCALE_F;
	unsigned int iremainder = len % SCALE_F;
	unsigned long *ptmp = (unsigned long *)p;

	while (iquotient--) {
		__asm__ __volatile__(
			".byte 0xf2, " REX_PRE "0xf, 0x38, 0xf1, 0xf1;"
			:"=S"(crc)
			:"0"(crc), "c"(*ptmp)
		);
		ptmp++;
	}

	if (iremainder)
		crc = crc32c_intel_le_hw_byte(crc, (unsigned char *)ptmp,
				 iremainder);

	return crc;
}

/*
 * Setting the seed allows arbitrary accumulators and flexible XOR policy
 * If your algorithm starts with ~0, then XOR with ~0 before you set
 * the seed.
 */
static int crc32c_intel_setkey(struct crypto_shash *hash, const u8 *key,
			unsigned int keylen)
{
	u32 *mctx = crypto_shash_ctx(hash);

	if (keylen != sizeof(u32)) {
		crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
		return -EINVAL;
	}
	*mctx = le32_to_cpup((__le32 *)key);
	return 0;
}

static int crc32c_intel_init(struct shash_desc *desc)
{
	u32 *mctx = crypto_shash_ctx(desc->tfm);
	u32 *crcp = shash_desc_ctx(desc);

	*crcp = *mctx;

	return 0;
}

static int crc32c_intel_update(struct shash_desc *desc, const u8 *data,
			       unsigned int len)
{
	u32 *crcp = shash_desc_ctx(desc);

	*crcp = crc32c_intel_le_hw(*crcp, data, len);
	return 0;
}

static int __crc32c_intel_finup(u32 *crcp, const u8 *data, unsigned int len,
				u8 *out)
{
	*(__le32 *)out = ~cpu_to_le32(crc32c_intel_le_hw(*crcp, data, len));
	return 0;
}

static int crc32c_intel_finup(struct shash_desc *desc, const u8 *data,
			      unsigned int len, u8 *out)
{
	return __crc32c_intel_finup(shash_desc_ctx(desc), data, len, out);
}

static int crc32c_intel_final(struct shash_desc *desc, u8 *out)
{
	u32 *crcp = shash_desc_ctx(desc);

	*(__le32 *)out = ~cpu_to_le32p(crcp);
	return 0;
}

static int crc32c_intel_digest(struct shash_desc *desc, const u8 *data,
			       unsigned int len, u8 *out)
{
	return __crc32c_intel_finup(crypto_shash_ctx(desc->tfm), data, len,
				    out);
}

static int crc32c_intel_cra_init(struct crypto_tfm *tfm)
{
	u32 *key = crypto_tfm_ctx(tfm);

	*key = ~0;

	return 0;
}

static struct shash_alg alg = {
	.setkey			=	crc32c_intel_setkey,
	.init			=	crc32c_intel_init,
	.update			=	crc32c_intel_update,
	.final			=	crc32c_intel_final,
	.finup			=	crc32c_intel_finup,
	.digest			=	crc32c_intel_digest,
	.descsize		=	sizeof(u32),
	.digestsize		=	CHKSUM_DIGEST_SIZE,
	.base			=	{
		.cra_name		=	"crc32c",
		.cra_driver_name	=	"crc32c-intel",
		.cra_priority		=	200,
		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
		.cra_ctxsize		=	sizeof(u32),
		.cra_module		=	THIS_MODULE,
		.cra_init		=	crc32c_intel_cra_init,
	}
};

static const struct x86_cpu_id crc32c_cpu_id[] = {
	X86_FEATURE_MATCH(X86_FEATURE_XMM4_2),
	{}
};
MODULE_DEVICE_TABLE(x86cpu, crc32c_cpu_id);

static int __init crc32c_intel_mod_init(void)
{
	if (!x86_match_cpu(crc32c_cpu_id))
		return -ENODEV;
	return crypto_register_shash(&alg);
}

static void __exit crc32c_intel_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}

module_init(crc32c_intel_mod_init);
module_exit(crc32c_intel_mod_fini);

MODULE_AUTHOR("Austin Zhang <austin.zhang@intel.com>, Kent Liu <kent.liu@intel.com>");
MODULE_DESCRIPTION("CRC32c (Castagnoli) optimization using Intel Hardware.");
MODULE_LICENSE("GPL");

MODULE_ALIAS("crc32c");
MODULE_ALIAS("crc32c-intel");
Commit	Line	Data
8cb51ba8 AZ	1	/*
	2	* Using hardware provided CRC32 instruction to accelerate the CRC32 disposal.
	3	* CRC32C polynomial:0x1EDC6F41(BE)/0x82F63B78(LE)
	4	* CRC32 is a new instruction in Intel SSE4.2, the reference can be found at:
	5	* http://www.intel.com/products/processor/manuals/
	6	* Intel(R) 64 and IA-32 Architectures Software Developer's Manual
	7	* Volume 2A: Instruction Set Reference, A-M
	8	*
1c06da81 KL	9	* Copyright (C) 2008 Intel Corporation
	10	* Authors: Austin Zhang <austin_zhang@linux.intel.com>
	11	* Kent Liu <kent.liu@intel.com>
8cb51ba8 AZ	12	*
8cb51ba8 AZ	13	* This program is free software; you can redistribute it and/or modify it
1c06da81 KL	14	* under the terms and conditions of the GNU General Public License,
	15	* version 2, as published by the Free Software Foundation.
	16	*
	17	* This program is distributed in the hope it will be useful, but WITHOUT
	18	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	19	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	20	* more details.
	21	*
	22	* You should have received a copy of the GNU General Public License along with
	23	* this program; if not, write to the Free Software Foundation, Inc.,
	24	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
8cb51ba8 AZ	25	*
	26	*/
	27	#include <linux/init.h>
	28	#include <linux/module.h>
	29	#include <linux/string.h>
	30	#include <linux/kernel.h>
	31	#include <crypto/internal/hash.h>
	32
	33	#include <asm/cpufeature.h>
3bd391f0	34	#include <asm/cpu_device_id.h>
8cb51ba8 AZ	35
	36	#define CHKSUM_BLOCK_SIZE 1
	37	#define CHKSUM_DIGEST_SIZE 4
	38
	39	#define SCALE_F sizeof(unsigned long)
	40
	41	#ifdef CONFIG_X86_64
	42	#define REX_PRE "0x48, "
	43	#else
	44	#define REX_PRE
	45	#endif
	46
	47	static u32 crc32c_intel_le_hw_byte(u32 crc, unsigned char const *data, size_t length)
	48	{
	49	while (length--) {
	50	__asm__ __volatile__(
	51	".byte 0xf2, 0xf, 0x38, 0xf0, 0xf1"
	52	:"=S"(crc)
	53	:"0"(crc), "c"(*data)
	54	);
	55	data++;
	56	}
	57
	58	return crc;
	59	}
	60
	61	static u32 __pure crc32c_intel_le_hw(u32 crc, unsigned char const *p, size_t len)
	62	{
	63	unsigned int iquotient = len / SCALE_F;
	64	unsigned int iremainder = len % SCALE_F;
	65	unsigned long ptmp = (unsigned long )p;
	66
	67	while (iquotient--) {
	68	__asm__ __volatile__(
	69	".byte 0xf2, " REX_PRE "0xf, 0x38, 0xf1, 0xf1;"
	70	:"=S"(crc)
	71	:"0"(crc), "c"(*ptmp)
	72	);
	73	ptmp++;
	74	}
	75
	76	if (iremainder)
	77	crc = crc32c_intel_le_hw_byte(crc, (unsigned char *)ptmp,
	78	iremainder);
	79
	80	return crc;
	81	}
	82
	83	/*
	84	* Setting the seed allows arbitrary accumulators and flexible XOR policy
	85	* If your algorithm starts with ~0, then XOR with ~0 before you set
	86	* the seed.
	87	*/
b7e8bdad	88	static int crc32c_intel_setkey(struct crypto_shash hash, const u8 key,
8cb51ba8 AZ	89	unsigned int keylen)
8cb51ba8 AZ	90	{
b7e8bdad	91	u32 *mctx = crypto_shash_ctx(hash);
8cb51ba8 AZ	92
8cb51ba8 AZ	93	if (keylen != sizeof(u32)) {
b7e8bdad	94	crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
8cb51ba8 AZ	95	return -EINVAL;
	96	}
	97	mctx = le32_to_cpup((__le32 )key);
	98	return 0;
	99	}
	100
b7e8bdad	101	static int crc32c_intel_init(struct shash_desc *desc)
8cb51ba8	102	{
b7e8bdad HX	103	u32 *mctx = crypto_shash_ctx(desc->tfm);
b7e8bdad HX	104	u32 *crcp = shash_desc_ctx(desc);
8cb51ba8 AZ	105
	106	crcp = mctx;
	107
	108	return 0;
	109	}
	110
b7e8bdad HX	111	static int crc32c_intel_update(struct shash_desc desc, const u8 data,
b7e8bdad HX	112	unsigned int len)
8cb51ba8	113	{
b7e8bdad	114	u32 *crcp = shash_desc_ctx(desc);
8cb51ba8	115
b7e8bdad	116	crcp = crc32c_intel_le_hw(crcp, data, len);
8cb51ba8 AZ	117	return 0;
	118	}
	119
b7e8bdad HX	120	static int __crc32c_intel_finup(u32 crcp, const u8 data, unsigned int len,
b7e8bdad HX	121	u8 *out)
8cb51ba8	122	{
b7e8bdad	123	(__le32 )out = ~cpu_to_le32(crc32c_intel_le_hw(*crcp, data, len));
8cb51ba8 AZ	124	return 0;
	125	}
	126
b7e8bdad HX	127	static int crc32c_intel_finup(struct shash_desc desc, const u8 data,
b7e8bdad HX	128	unsigned int len, u8 *out)
8cb51ba8	129	{
b7e8bdad HX	130	return __crc32c_intel_finup(shash_desc_ctx(desc), data, len, out);
b7e8bdad HX	131	}
8cb51ba8	132
b7e8bdad HX	133	static int crc32c_intel_final(struct shash_desc desc, u8 out)
	134	{
	135	u32 *crcp = shash_desc_ctx(desc);
8cb51ba8	136
b7e8bdad	137	(__le32 )out = ~cpu_to_le32p(crcp);
8cb51ba8 AZ	138	return 0;
	139	}
	140
b7e8bdad HX	141	static int crc32c_intel_digest(struct shash_desc desc, const u8 data,
	142	unsigned int len, u8 *out)
	143	{
	144	return __crc32c_intel_finup(crypto_shash_ctx(desc->tfm), data, len,
	145	out);
	146	}
	147
8cb51ba8 AZ	148	static int crc32c_intel_cra_init(struct crypto_tfm *tfm)
	149	{
	150	u32 *key = crypto_tfm_ctx(tfm);
	151
	152	*key = ~0;
	153
8cb51ba8 AZ	154	return 0;
	155	}
	156
b7e8bdad HX	157	static struct shash_alg alg = {
	158	.setkey = crc32c_intel_setkey,
	159	.init = crc32c_intel_init,
	160	.update = crc32c_intel_update,
	161	.final = crc32c_intel_final,
	162	.finup = crc32c_intel_finup,
	163	.digest = crc32c_intel_digest,
	164	.descsize = sizeof(u32),
	165	.digestsize = CHKSUM_DIGEST_SIZE,
	166	.base = {
	167	.cra_name = "crc32c",
	168	.cra_driver_name = "crc32c-intel",
	169	.cra_priority = 200,
	170	.cra_blocksize = CHKSUM_BLOCK_SIZE,
	171	.cra_ctxsize = sizeof(u32),
	172	.cra_module = THIS_MODULE,
	173	.cra_init = crc32c_intel_cra_init,
8cb51ba8 AZ	174	}
	175	};
	176
3bd391f0 AK	177	static const struct x86_cpu_id crc32c_cpu_id[] = {
	178	X86_FEATURE_MATCH(X86_FEATURE_XMM4_2),
	179	{}
	180	};
	181	MODULE_DEVICE_TABLE(x86cpu, crc32c_cpu_id);
8cb51ba8 AZ	182
	183	static int __init crc32c_intel_mod_init(void)
	184	{
3bd391f0	185	if (!x86_match_cpu(crc32c_cpu_id))
8cb51ba8	186	return -ENODEV;
3bd391f0	187	return crypto_register_shash(&alg);
8cb51ba8 AZ	188	}
	189
	190	static void __exit crc32c_intel_mod_fini(void)
	191	{
b7e8bdad	192	crypto_unregister_shash(&alg);
8cb51ba8 AZ	193	}
	194
	195	module_init(crc32c_intel_mod_init);
	196	module_exit(crc32c_intel_mod_fini);
	197
	198	MODULE_AUTHOR("Austin Zhang <austin.zhang@intel.com>, Kent Liu <kent.liu@intel.com>");
	199	MODULE_DESCRIPTION("CRC32c (Castagnoli) optimization using Intel Hardware.");
	200	MODULE_LICENSE("GPL");
	201
	202	MODULE_ALIAS("crc32c");
	203	MODULE_ALIAS("crc32c-intel");