Commit f6f203fa authored by Yazen Ghannam's avatar Yazen Ghannam Committed by Herbert Xu
Browse files

crypto: crc32 - Add ARM64 CRC32 hw accelerated module 



This module registers a crc32 algorithm and a crc32c algorithm
that use the optional CRC32 and CRC32C instructions in ARMv8.

Tested on AMD Seattle.

Improvement compared to crc32c-generic algorithm:
TCRYPT CRC32C speed test shows ~450% speedup.
Simple dd write tests to btrfs filesystem show ~30% speedup.

Signed-off-by: default avatarYazen Ghannam <yazen.ghannam@linaro.org>
Acked-by: default avatarSteve Capper <steve.capper@linaro.org>
Acked-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent aa408d60

arch/arm64/crypto/Kconfig

+4 −0
Original line number Diff line number Diff line
@@ -50,4 +50,8 @@ config CRYPTO_AES_ARM64_NEON_BLK 
	select CRYPTO_AES

	select CRYPTO_ABLK_HELPER



config CRYPTO_CRC32_ARM64

	tristate "CRC32 and CRC32C using optional ARMv8 instructions"

	depends on ARM64

	select CRYPTO_HASH

endif

arch/arm64/crypto/Makefile

+4 −0
Original line number Diff line number Diff line
@@ -34,5 +34,9 @@ AFLAGS_aes-neon.o := -DINTERLEAVE=4 


CFLAGS_aes-glue-ce.o	:= -DUSE_V8_CRYPTO_EXTENSIONS



obj-$(CONFIG_CRYPTO_CRC32_ARM64) += crc32-arm64.o



CFLAGS_crc32-arm64.o	:= -mcpu=generic+crc



$(obj)/aes-glue-%.o: $(src)/aes-glue.c FORCE

	$(call if_changed_rule,cc_o_c)

arch/arm64/crypto/crc32-arm64.c

0 → 100644
+274 −0
Original line number Diff line number Diff line 
/*

 * crc32-arm64.c - CRC32 and CRC32C using optional ARMv8 instructions

 *

 * Module based on crypto/crc32c_generic.c

 *

 * CRC32 loop taken from Ed Nevill's Hadoop CRC patch

 * http://mail-archives.apache.org/mod_mbox/hadoop-common-dev/201406.mbox/%3C1403687030.3355.19.camel%40localhost.localdomain%3E

 *

 * Using inline assembly instead of intrinsics in order to be backwards

 * compatible with older compilers.

 *

 * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */



#include <linux/unaligned/access_ok.h>

#include <linux/cpufeature.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/string.h>



#include <crypto/internal/hash.h>



MODULE_AUTHOR("Yazen Ghannam <yazen.ghannam@linaro.org>");

MODULE_DESCRIPTION("CRC32 and CRC32C using optional ARMv8 instructions");

MODULE_LICENSE("GPL v2");



#define CRC32X(crc, value) __asm__("crc32x %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32W(crc, value) __asm__("crc32w %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32H(crc, value) __asm__("crc32h %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32B(crc, value) __asm__("crc32b %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32CX(crc, value) __asm__("crc32cx %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32CW(crc, value) __asm__("crc32cw %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32CH(crc, value) __asm__("crc32ch %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

#define CRC32CB(crc, value) __asm__("crc32cb %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))



static u32 crc32_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)

{

	s64 length = len;



	while ((length -= sizeof(u64)) >= 0) {

		CRC32X(crc, get_unaligned_le64(p));

		p += sizeof(u64);

	}



	/* The following is more efficient than the straight loop */

	if (length & sizeof(u32)) {

		CRC32W(crc, get_unaligned_le32(p));

		p += sizeof(u32);

	}

	if (length & sizeof(u16)) {

		CRC32H(crc, get_unaligned_le16(p));

		p += sizeof(u16);

	}

	if (length & sizeof(u8))

		CRC32B(crc, *p);



	return crc;

}



static u32 crc32c_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)

{

	s64 length = len;



	while ((length -= sizeof(u64)) >= 0) {

		CRC32CX(crc, get_unaligned_le64(p));

		p += sizeof(u64);

	}



	/* The following is more efficient than the straight loop */

	if (length & sizeof(u32)) {

		CRC32CW(crc, get_unaligned_le32(p));

		p += sizeof(u32);

	}

	if (length & sizeof(u16)) {

		CRC32CH(crc, get_unaligned_le16(p));

		p += sizeof(u16);

	}

	if (length & sizeof(u8))

		CRC32CB(crc, *p);



	return crc;

}



#define CHKSUM_BLOCK_SIZE	1

#define CHKSUM_DIGEST_SIZE	4



struct chksum_ctx {

	u32 key;

};



struct chksum_desc_ctx {

	u32 crc;

};



static int chksum_init(struct shash_desc *desc)

{

	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);

	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);



	ctx->crc = mctx->key;



	return 0;

}



/*

 * 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 chksum_setkey(struct crypto_shash *tfm, const u8 *key,

			 unsigned int keylen)

{

	struct chksum_ctx *mctx = crypto_shash_ctx(tfm);



	if (keylen != sizeof(mctx->key)) {

		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);

		return -EINVAL;

	}

	mctx->key = get_unaligned_le32(key);

	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);



	ctx->crc = crc32_arm64_le_hw(ctx->crc, data, length);

	return 0;

}



static int chksumc_update(struct shash_desc *desc, const u8 *data,

			 unsigned int length)

{

	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);



	ctx->crc = crc32c_arm64_le_hw(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);



	put_unaligned_le32(~ctx->crc, out);

	return 0;

}



static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)

{

	put_unaligned_le32(~crc32_arm64_le_hw(crc, data, len), out);

	return 0;

}



static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)

{

	put_unaligned_le32(~crc32c_arm64_le_hw(crc, data, len), out);

	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 chksumc_finup(struct shash_desc *desc, const u8 *data,

			unsigned int len, u8 *out)

{

	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);



	return __chksumc_finup(ctx->crc, data, len, out);

}



static int chksum_digest(struct shash_desc *desc, const u8 *data,

			 unsigned int length, u8 *out)

{

	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);



	return __chksum_finup(mctx->key, data, length, out);

}



static int chksumc_digest(struct shash_desc *desc, const u8 *data,

			 unsigned int length, u8 *out)

{

	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);



	return __chksumc_finup(mctx->key, data, length, out);

}



static int crc32_cra_init(struct crypto_tfm *tfm)

{

	struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);



	mctx->key = ~0;

	return 0;

}



static struct shash_alg crc32_alg = {

	.digestsize		=	CHKSUM_DIGEST_SIZE,

	.setkey			=	chksum_setkey,

	.init			=	chksum_init,

	.update			=	chksum_update,

	.final			=	chksum_final,

	.finup			=	chksum_finup,

	.digest			=	chksum_digest,

	.descsize		=	sizeof(struct chksum_desc_ctx),

	.base			=	{

		.cra_name		=	"crc32",

		.cra_driver_name	=	"crc32-arm64-hw",

		.cra_priority		=	300,

		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,

		.cra_alignmask		=	0,

		.cra_ctxsize		=	sizeof(struct chksum_ctx),

		.cra_module		=	THIS_MODULE,

		.cra_init		=	crc32_cra_init,

	}

};



static struct shash_alg crc32c_alg = {

	.digestsize		=	CHKSUM_DIGEST_SIZE,

	.setkey			=	chksum_setkey,

	.init			=	chksum_init,

	.update			=	chksumc_update,

	.final			=	chksum_final,

	.finup			=	chksumc_finup,

	.digest			=	chksumc_digest,

	.descsize		=	sizeof(struct chksum_desc_ctx),

	.base			=	{

		.cra_name		=	"crc32c",

		.cra_driver_name	=	"crc32c-arm64-hw",

		.cra_priority		=	300,

		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,

		.cra_alignmask		=	0,

		.cra_ctxsize		=	sizeof(struct chksum_ctx),

		.cra_module		=	THIS_MODULE,

		.cra_init		=	crc32_cra_init,

	}

};



static int __init crc32_mod_init(void)

{

	int err;



	err = crypto_register_shash(&crc32_alg);



	if (err)

		return err;



	err = crypto_register_shash(&crc32c_alg);



	if (err) {

		crypto_unregister_shash(&crc32_alg);

		return err;

	}



	return 0;

}



static void __exit crc32_mod_exit(void)

{

	crypto_unregister_shash(&crc32_alg);

	crypto_unregister_shash(&crc32c_alg);

}



module_cpu_feature_match(CRC32, crc32_mod_init);

module_exit(crc32_mod_exit);

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