Commit 1684e829 authored by Eric Biggers's avatar Eric Biggers
Browse files

arm/crc-t10dif: expose CRC-T10DIF function through lib 



Move the arm CRC-T10DIF assembly code into the lib directory and wire it
up to the library interface.  This allows it to be used without going
through the crypto API.  It remains usable via the crypto API too via
the shash algorithms that use the library interface.  Thus all the
arch-specific "shash" code becomes unnecessary and is removed.

Note: to see the diff from arch/arm/crypto/crct10dif-ce-glue.c to
arch/arm/lib/crc-t10dif-glue.c, view this commit with 'git show -M10'.

Reviewed-by: default avatarArd Biesheuvel <ardb@kernel.org>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20241202012056.209768-6-ebiggers@kernel.org


Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
parent ed4bc981

arch/arm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ config ARM 
	select ARCH_HAS_CPU_CACHE_ALIASING

	select ARCH_HAS_CPU_FINALIZE_INIT if MMU

	select ARCH_HAS_CRC32 if KERNEL_MODE_NEON

	select ARCH_HAS_CRC_T10DIF if KERNEL_MODE_NEON

	select ARCH_HAS_CURRENT_STACK_POINTER

	select ARCH_HAS_DEBUG_VIRTUAL if MMU

	select ARCH_HAS_DMA_ALLOC if MMU

arch/arm/crypto/Kconfig

+0 −11
Original line number Diff line number Diff line
@@ -222,16 +222,5 @@ config CRYPTO_CHACHA20_NEON 
	  Architecture: arm using:

	  - NEON (Advanced SIMD) extensions



config CRYPTO_CRCT10DIF_ARM_CE

	tristate "CRCT10DIF"

	depends on KERNEL_MODE_NEON

	depends on CRC_T10DIF

	select CRYPTO_HASH

	help

	  CRC16 CRC algorithm used for the T10 (SCSI) Data Integrity Field (DIF)



	  Architecture: arm using:

	  - PMULL (Polynomial Multiply Long) instructions



endmenu

arch/arm/crypto/Makefile

+0 −2
Original line number Diff line number Diff line
@@ -20,7 +20,6 @@ obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o 
obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o

obj-$(CONFIG_CRYPTO_SHA2_ARM_CE) += sha2-arm-ce.o

obj-$(CONFIG_CRYPTO_GHASH_ARM_CE) += ghash-arm-ce.o

obj-$(CONFIG_CRYPTO_CRCT10DIF_ARM_CE) += crct10dif-arm-ce.o



aes-arm-y	:= aes-cipher-core.o aes-cipher-glue.o

aes-arm-bs-y	:= aes-neonbs-core.o aes-neonbs-glue.o
@@ -36,7 +35,6 @@ sha1-arm-ce-y := sha1-ce-core.o sha1-ce-glue.o 
sha2-arm-ce-y	:= sha2-ce-core.o sha2-ce-glue.o

aes-arm-ce-y	:= aes-ce-core.o aes-ce-glue.o

ghash-arm-ce-y	:= ghash-ce-core.o ghash-ce-glue.o

crct10dif-arm-ce-y	:= crct10dif-ce-core.o crct10dif-ce-glue.o

chacha-neon-y := chacha-scalar-core.o chacha-glue.o

chacha-neon-$(CONFIG_KERNEL_MODE_NEON) += chacha-neon-core.o

poly1305-arm-y := poly1305-core.o poly1305-glue.o

arch/arm/crypto/crct10dif-ce-glue.c

deleted100644 → 0
+0 −124
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Accelerated CRC-T10DIF using ARM NEON and Crypto Extensions instructions

 *

 * Copyright (C) 2016 Linaro Ltd <ard.biesheuvel@linaro.org>

 */



#include <linux/crc-t10dif.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/string.h>



#include <crypto/internal/hash.h>

#include <crypto/internal/simd.h>



#include <asm/neon.h>

#include <asm/simd.h>



#define CRC_T10DIF_PMULL_CHUNK_SIZE	16U



asmlinkage u16 crc_t10dif_pmull64(u16 init_crc, const u8 *buf, size_t len);

asmlinkage void crc_t10dif_pmull8(u16 init_crc, const u8 *buf, size_t len,

				  u8 out[16]);



static int crct10dif_init(struct shash_desc *desc)

{

	u16 *crc = shash_desc_ctx(desc);



	*crc = 0;

	return 0;

}



static int crct10dif_update_ce(struct shash_desc *desc, const u8 *data,

			       unsigned int length)

{

	u16 *crc = shash_desc_ctx(desc);



	if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && crypto_simd_usable()) {

		kernel_neon_begin();

		*crc = crc_t10dif_pmull64(*crc, data, length);

		kernel_neon_end();

	} else {

		*crc = crc_t10dif_generic(*crc, data, length);

	}



	return 0;

}



static int crct10dif_update_neon(struct shash_desc *desc, const u8 *data,

			         unsigned int length)

{

	u16 *crcp = shash_desc_ctx(desc);

	u8 buf[16] __aligned(16);

	u16 crc = *crcp;



	if (length > CRC_T10DIF_PMULL_CHUNK_SIZE && crypto_simd_usable()) {

		kernel_neon_begin();

		crc_t10dif_pmull8(crc, data, length, buf);

		kernel_neon_end();



		crc = 0;

		data = buf;

		length = sizeof(buf);

	}



	*crcp = crc_t10dif_generic(crc, data, length);

	return 0;

}



static int crct10dif_final(struct shash_desc *desc, u8 *out)

{

	u16 *crc = shash_desc_ctx(desc);



	*(u16 *)out = *crc;

	return 0;

}



static struct shash_alg algs[] = {{

	.digestsize		= CRC_T10DIF_DIGEST_SIZE,

	.init			= crct10dif_init,

	.update			= crct10dif_update_neon,

	.final			= crct10dif_final,

	.descsize		= CRC_T10DIF_DIGEST_SIZE,



	.base.cra_name		= "crct10dif",

	.base.cra_driver_name	= "crct10dif-arm-neon",

	.base.cra_priority	= 150,

	.base.cra_blocksize	= CRC_T10DIF_BLOCK_SIZE,

	.base.cra_module	= THIS_MODULE,

}, {

	.digestsize		= CRC_T10DIF_DIGEST_SIZE,

	.init			= crct10dif_init,

	.update			= crct10dif_update_ce,

	.final			= crct10dif_final,

	.descsize		= CRC_T10DIF_DIGEST_SIZE,



	.base.cra_name		= "crct10dif",

	.base.cra_driver_name	= "crct10dif-arm-ce",

	.base.cra_priority	= 200,

	.base.cra_blocksize	= CRC_T10DIF_BLOCK_SIZE,

	.base.cra_module	= THIS_MODULE,

}};



static int __init crc_t10dif_mod_init(void)

{

	if (!(elf_hwcap & HWCAP_NEON))

		return -ENODEV;



	return crypto_register_shashes(algs, 1 + !!(elf_hwcap2 & HWCAP2_PMULL));

}



static void __exit crc_t10dif_mod_exit(void)

{

	crypto_unregister_shashes(algs, 1 + !!(elf_hwcap2 & HWCAP2_PMULL));

}



module_init(crc_t10dif_mod_init);

module_exit(crc_t10dif_mod_exit);



MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");

MODULE_DESCRIPTION("Accelerated CRC-T10DIF using ARM NEON and Crypto Extensions");

MODULE_LICENSE("GPL v2");

MODULE_ALIAS_CRYPTO("crct10dif");

arch/arm/lib/Makefile

+3 −0
Original line number Diff line number Diff line
@@ -48,3 +48,6 @@ obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o 


obj-$(CONFIG_CRC32_ARCH) += crc32-arm.o

crc32-arm-y := crc32-glue.o crc32-core.o



obj-$(CONFIG_CRC_T10DIF_ARCH) += crc-t10dif-arm.o

crc-t10dif-arm-y := crc-t10dif-glue.o crc-t10dif-core.o