From patchwork Mon Dec 2 01:08:33 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 846742 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 656A914A0B8; Mon, 2 Dec 2024 01:09:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733101774; cv=none; b=fm3tXJLgdWc5KDirvbTtFO/RkyAwR9x0K2yM2Sl7q6SYrZUA99oSdFV+WVAowtXnnJVWAUzKWIS39CW4WxaJp3fLcn2rQm2C+iAhc0hkZnY9lmoWn/Vfa1RW5HFtAinSeyjlvGwKw/Z6iSfDDnCBcSYvQx6fvivn4chcOCJGSj8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733101774; c=relaxed/simple; bh=gTqOZxWuUMOtML33jITsoShS2PUWS/j+YXsuv+977g8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=X1E0A5tGFYCWWAR31Jwk5fgS+F/yyJiXPmrCdMtCwJQazyutrnO0N7JHzDGgXUdSL96SRVvV7zpaQDbjsP6DJkinF2R1St2v7KtNz7btaIB4sL/uQbIFoBG0jjOhttd7KrM2w0xxv+COygHDF1UNmbYmM31wL1+8bV2krsgF05E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=uZZ5KLDg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="uZZ5KLDg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E272C4CEE2; Mon, 2 Dec 2024 01:09:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733101773; bh=gTqOZxWuUMOtML33jITsoShS2PUWS/j+YXsuv+977g8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uZZ5KLDgQPO5MWhGcyygO7Y0QcFRy/j/0ePunZH4zrZWOuvBW7F81kR/WA779z8Fv qtyfH2yrGNA4ctW8YF/5ZfSJSviOY5Qj7toT4UV+iKqbpQA0rNg5FzTK/if55hpbx6 hXgtksF68aMDCyc9ZWtzVGb91HaBr21jk2BJGZ1sq8NAVqf3ug1WGQs9rWpfRMXJkw 7942zxQ47h8rtpmkcmfzx8uimpjAW5sBpNDJoEiQlTSwGjKkZjqRwgpX++CiZCiI+A 39CZdot87QUfzp+QigjWfwNNK4U0lzm7b9IHpScFMCfZo5bXhP4KVpGvkdcmo2TtGh 3BFfQ75hXMPwQ== From: Eric Biggers To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mips@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, sparclinux@vger.kernel.org, x86@kernel.org, Ard Biesheuvel , Michael Ellerman Subject: [PATCH v4 08/19] powerpc/crc32: expose CRC32 functions through lib Date: Sun, 1 Dec 2024 17:08:33 -0800 Message-ID: <20241202010844.144356-9-ebiggers@kernel.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241202010844.144356-1-ebiggers@kernel.org> References: <20241202010844.144356-1-ebiggers@kernel.org> Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Eric Biggers Move the powerpc CRC32C 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/powerpc/crypto/crc32c-vpmsum_glue.c to arch/powerpc/lib/crc32-glue.c, view this commit with 'git show -M10'. Reviewed-by: Ard Biesheuvel Acked-by: Michael Ellerman (powerpc) Signed-off-by: Eric Biggers --- arch/powerpc/Kconfig | 1 + arch/powerpc/configs/powernv_defconfig | 1 - arch/powerpc/configs/ppc64_defconfig | 1 - arch/powerpc/crypto/Kconfig | 15 +- arch/powerpc/crypto/Makefile | 2 - arch/powerpc/crypto/crc32c-vpmsum_glue.c | 173 ------------------ arch/powerpc/crypto/crct10dif-vpmsum_asm.S | 2 +- arch/powerpc/lib/Makefile | 3 + arch/powerpc/lib/crc32-glue.c | 92 ++++++++++ .../{crypto => lib}/crc32-vpmsum_core.S | 0 .../{crypto => lib}/crc32c-vpmsum_asm.S | 0 11 files changed, 98 insertions(+), 192 deletions(-) delete mode 100644 arch/powerpc/crypto/crc32c-vpmsum_glue.c create mode 100644 arch/powerpc/lib/crc32-glue.c rename arch/powerpc/{crypto => lib}/crc32-vpmsum_core.S (100%) rename arch/powerpc/{crypto => lib}/crc32c-vpmsum_asm.S (100%) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index a0ce777f9706..b5050a09a27f 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -125,10 +125,11 @@ config PPC select ARCH_DISABLE_KASAN_INLINE if PPC_RADIX_MMU select ARCH_DMA_DEFAULT_COHERENT if !NOT_COHERENT_CACHE select ARCH_ENABLE_MEMORY_HOTPLUG select ARCH_ENABLE_MEMORY_HOTREMOVE select ARCH_HAS_COPY_MC if PPC64 + select ARCH_HAS_CRC32 if PPC64 && ALTIVEC select ARCH_HAS_CURRENT_STACK_POINTER select ARCH_HAS_DEBUG_VIRTUAL select ARCH_HAS_DEBUG_VM_PGTABLE select ARCH_HAS_DEBUG_WX if STRICT_KERNEL_RWX select ARCH_HAS_DEVMEM_IS_ALLOWED diff --git a/arch/powerpc/configs/powernv_defconfig b/arch/powerpc/configs/powernv_defconfig index ee84ade7a033..4a7ddea05b4d 100644 --- a/arch/powerpc/configs/powernv_defconfig +++ b/arch/powerpc/configs/powernv_defconfig @@ -318,11 +318,10 @@ CONFIG_FTR_FIXUP_SELFTEST=y CONFIG_MSI_BITMAP_SELFTEST=y CONFIG_XMON=y CONFIG_CRYPTO_TEST=m CONFIG_CRYPTO_PCBC=m CONFIG_CRYPTO_HMAC=y -CONFIG_CRYPTO_CRC32C_VPMSUM=m CONFIG_CRYPTO_CRCT10DIF_VPMSUM=m CONFIG_CRYPTO_MD5_PPC=m CONFIG_CRYPTO_MICHAEL_MIC=m CONFIG_CRYPTO_SHA1_PPC=m CONFIG_CRYPTO_SHA256=y diff --git a/arch/powerpc/configs/ppc64_defconfig b/arch/powerpc/configs/ppc64_defconfig index f39c0d000c43..58e5f4488da4 100644 --- a/arch/powerpc/configs/ppc64_defconfig +++ b/arch/powerpc/configs/ppc64_defconfig @@ -387,11 +387,10 @@ CONFIG_CRYPTO_TWOFISH=m CONFIG_CRYPTO_PCBC=m CONFIG_CRYPTO_MICHAEL_MIC=m CONFIG_CRYPTO_SHA256=y CONFIG_CRYPTO_WP512=m CONFIG_CRYPTO_LZO=m -CONFIG_CRYPTO_CRC32C_VPMSUM=m CONFIG_CRYPTO_CRCT10DIF_VPMSUM=m CONFIG_CRYPTO_VPMSUM_TESTER=m CONFIG_CRYPTO_MD5_PPC=m CONFIG_CRYPTO_SHA1_PPC=m CONFIG_CRYPTO_AES_GCM_P10=m diff --git a/arch/powerpc/crypto/Kconfig b/arch/powerpc/crypto/Kconfig index 951a43726461..2d89e35b3cdd 100644 --- a/arch/powerpc/crypto/Kconfig +++ b/arch/powerpc/crypto/Kconfig @@ -11,23 +11,10 @@ config CRYPTO_CURVE25519_PPC64 Curve25519 algorithm Architecture: PowerPC64 - Little-endian -config CRYPTO_CRC32C_VPMSUM - tristate "CRC32c" - depends on PPC64 && ALTIVEC - select CRYPTO_HASH - select CRC32 - help - CRC32c CRC algorithm with the iSCSI polynomial (RFC 3385 and RFC 3720) - - Architecture: powerpc64 using - - AltiVec extensions - - Enable on POWER8 and newer processors for improved performance. - config CRYPTO_CRCT10DIF_VPMSUM tristate "CRC32T10DIF" depends on PPC64 && ALTIVEC && CRC_T10DIF select CRYPTO_HASH help @@ -38,11 +25,11 @@ config CRYPTO_CRCT10DIF_VPMSUM Enable on POWER8 and newer processors for improved performance. config CRYPTO_VPMSUM_TESTER tristate "CRC32c and CRC32T10DIF hardware acceleration tester" - depends on CRYPTO_CRCT10DIF_VPMSUM && CRYPTO_CRC32C_VPMSUM + depends on CRYPTO_CRCT10DIF_VPMSUM && CRYPTO_CRC32C && CRC32_ARCH help Stress test for CRC32c and CRCT10DIF algorithms implemented with powerpc64 AltiVec extensions (POWER8 vpmsum instructions). Unless you are testing these algorithms, you don't need this. diff --git a/arch/powerpc/crypto/Makefile b/arch/powerpc/crypto/Makefile index 59808592f0a1..54486192273c 100644 --- a/arch/powerpc/crypto/Makefile +++ b/arch/powerpc/crypto/Makefile @@ -8,11 +8,10 @@ obj-$(CONFIG_CRYPTO_AES_PPC_SPE) += aes-ppc-spe.o obj-$(CONFIG_CRYPTO_MD5_PPC) += md5-ppc.o obj-$(CONFIG_CRYPTO_SHA1_PPC) += sha1-powerpc.o obj-$(CONFIG_CRYPTO_SHA1_PPC_SPE) += sha1-ppc-spe.o obj-$(CONFIG_CRYPTO_SHA256_PPC_SPE) += sha256-ppc-spe.o -obj-$(CONFIG_CRYPTO_CRC32C_VPMSUM) += crc32c-vpmsum.o obj-$(CONFIG_CRYPTO_CRCT10DIF_VPMSUM) += crct10dif-vpmsum.o obj-$(CONFIG_CRYPTO_VPMSUM_TESTER) += crc-vpmsum_test.o obj-$(CONFIG_CRYPTO_AES_GCM_P10) += aes-gcm-p10-crypto.o obj-$(CONFIG_CRYPTO_CHACHA20_P10) += chacha-p10-crypto.o obj-$(CONFIG_CRYPTO_POLY1305_P10) += poly1305-p10-crypto.o @@ -22,11 +21,10 @@ obj-$(CONFIG_CRYPTO_CURVE25519_PPC64) += curve25519-ppc64le.o aes-ppc-spe-y := aes-spe-core.o aes-spe-keys.o aes-tab-4k.o aes-spe-modes.o aes-spe-glue.o md5-ppc-y := md5-asm.o md5-glue.o sha1-powerpc-y := sha1-powerpc-asm.o sha1.o sha1-ppc-spe-y := sha1-spe-asm.o sha1-spe-glue.o sha256-ppc-spe-y := sha256-spe-asm.o sha256-spe-glue.o -crc32c-vpmsum-y := crc32c-vpmsum_asm.o crc32c-vpmsum_glue.o crct10dif-vpmsum-y := crct10dif-vpmsum_asm.o crct10dif-vpmsum_glue.o aes-gcm-p10-crypto-y := aes-gcm-p10-glue.o aes-gcm-p10.o ghashp10-ppc.o aesp10-ppc.o chacha-p10-crypto-y := chacha-p10-glue.o chacha-p10le-8x.o poly1305-p10-crypto-y := poly1305-p10-glue.o poly1305-p10le_64.o vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o aes_cbc.o aes_ctr.o aes_xts.o ghash.o diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c b/arch/powerpc/crypto/crc32c-vpmsum_glue.c deleted file mode 100644 index 63760b7dbb76..000000000000 --- a/arch/powerpc/crypto/crc32c-vpmsum_glue.c +++ /dev/null @@ -1,173 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#define CHKSUM_BLOCK_SIZE 1 -#define CHKSUM_DIGEST_SIZE 4 - -#define VMX_ALIGN 16 -#define VMX_ALIGN_MASK (VMX_ALIGN-1) - -#define VECTOR_BREAKPOINT 512 - -u32 __crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len); - -static u32 crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len) -{ - unsigned int prealign; - unsigned int tail; - - if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || !crypto_simd_usable()) - return __crc32c_le(crc, p, len); - - if ((unsigned long)p & VMX_ALIGN_MASK) { - prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK); - crc = __crc32c_le(crc, p, prealign); - len -= prealign; - p += prealign; - } - - if (len & ~VMX_ALIGN_MASK) { - preempt_disable(); - pagefault_disable(); - enable_kernel_altivec(); - crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK); - disable_kernel_altivec(); - pagefault_enable(); - preempt_enable(); - } - - tail = len & VMX_ALIGN_MASK; - if (tail) { - p += len & ~VMX_ALIGN_MASK; - crc = __crc32c_le(crc, p, tail); - } - - return crc; -} - -static int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm) -{ - u32 *key = crypto_tfm_ctx(tfm); - - *key = ~0; - - 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 crc32c_vpmsum_setkey(struct crypto_shash *hash, const u8 *key, - unsigned int keylen) -{ - u32 *mctx = crypto_shash_ctx(hash); - - if (keylen != sizeof(u32)) - return -EINVAL; - *mctx = le32_to_cpup((__le32 *)key); - return 0; -} - -static int crc32c_vpmsum_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_vpmsum_update(struct shash_desc *desc, const u8 *data, - unsigned int len) -{ - u32 *crcp = shash_desc_ctx(desc); - - *crcp = crc32c_vpmsum(*crcp, data, len); - - return 0; -} - -static int __crc32c_vpmsum_finup(u32 *crcp, const u8 *data, unsigned int len, - u8 *out) -{ - *(__le32 *)out = ~cpu_to_le32(crc32c_vpmsum(*crcp, data, len)); - - return 0; -} - -static int crc32c_vpmsum_finup(struct shash_desc *desc, const u8 *data, - unsigned int len, u8 *out) -{ - return __crc32c_vpmsum_finup(shash_desc_ctx(desc), data, len, out); -} - -static int crc32c_vpmsum_final(struct shash_desc *desc, u8 *out) -{ - u32 *crcp = shash_desc_ctx(desc); - - *(__le32 *)out = ~cpu_to_le32p(crcp); - - return 0; -} - -static int crc32c_vpmsum_digest(struct shash_desc *desc, const u8 *data, - unsigned int len, u8 *out) -{ - return __crc32c_vpmsum_finup(crypto_shash_ctx(desc->tfm), data, len, - out); -} - -static struct shash_alg alg = { - .setkey = crc32c_vpmsum_setkey, - .init = crc32c_vpmsum_init, - .update = crc32c_vpmsum_update, - .final = crc32c_vpmsum_final, - .finup = crc32c_vpmsum_finup, - .digest = crc32c_vpmsum_digest, - .descsize = sizeof(u32), - .digestsize = CHKSUM_DIGEST_SIZE, - .base = { - .cra_name = "crc32c", - .cra_driver_name = "crc32c-vpmsum", - .cra_priority = 200, - .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .cra_blocksize = CHKSUM_BLOCK_SIZE, - .cra_ctxsize = sizeof(u32), - .cra_module = THIS_MODULE, - .cra_init = crc32c_vpmsum_cra_init, - } -}; - -static int __init crc32c_vpmsum_mod_init(void) -{ - if (!cpu_has_feature(CPU_FTR_ARCH_207S)) - return -ENODEV; - - return crypto_register_shash(&alg); -} - -static void __exit crc32c_vpmsum_mod_fini(void) -{ - crypto_unregister_shash(&alg); -} - -module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crc32c_vpmsum_mod_init); -module_exit(crc32c_vpmsum_mod_fini); - -MODULE_AUTHOR("Anton Blanchard "); -MODULE_DESCRIPTION("CRC32C using vector polynomial multiply-sum instructions"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_CRYPTO("crc32c"); -MODULE_ALIAS_CRYPTO("crc32c-vpmsum"); diff --git a/arch/powerpc/crypto/crct10dif-vpmsum_asm.S b/arch/powerpc/crypto/crct10dif-vpmsum_asm.S index f0b93a0fe168..0a52261bf859 100644 --- a/arch/powerpc/crypto/crct10dif-vpmsum_asm.S +++ b/arch/powerpc/crypto/crct10dif-vpmsum_asm.S @@ -840,6 +840,6 @@ .octa 0x000000000000000000000001f65a57f8 /* x^64 div p(x) */ /* Barrett constant n */ .octa 0x0000000000000000000000018bb70000 #define CRC_FUNCTION_NAME __crct10dif_vpmsum -#include "crc32-vpmsum_core.S" +#include "../lib/crc32-vpmsum_core.S" diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index f14ecab674a3..da9381a1c95b 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -76,6 +76,9 @@ obj-$(CONFIG_FTR_FIXUP_SELFTEST) += feature-fixups-test.o obj-$(CONFIG_ALTIVEC) += xor_vmx.o xor_vmx_glue.o CFLAGS_xor_vmx.o += -mhard-float -maltivec $(call cc-option,-mabi=altivec) # Enable CFLAGS_xor_vmx.o += -isystem $(shell $(CC) -print-file-name=include) +obj-$(CONFIG_CRC32_ARCH) += crc32-powerpc.o +crc32-powerpc-y := crc32-glue.o crc32c-vpmsum_asm.o + obj-$(CONFIG_PPC64) += $(obj64-y) diff --git a/arch/powerpc/lib/crc32-glue.c b/arch/powerpc/lib/crc32-glue.c new file mode 100644 index 000000000000..79cc954f499f --- /dev/null +++ b/arch/powerpc/lib/crc32-glue.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include +#include +#include +#include + +#define VMX_ALIGN 16 +#define VMX_ALIGN_MASK (VMX_ALIGN-1) + +#define VECTOR_BREAKPOINT 512 + +static DEFINE_STATIC_KEY_FALSE(have_vec_crypto); + +u32 __crc32c_vpmsum(u32 crc, const u8 *p, size_t len); + +u32 crc32_le_arch(u32 crc, const u8 *p, size_t len) +{ + return crc32_le_base(crc, p, len); +} +EXPORT_SYMBOL(crc32_le_arch); + +u32 crc32c_le_arch(u32 crc, const u8 *p, size_t len) +{ + unsigned int prealign; + unsigned int tail; + + if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || + !static_branch_likely(&have_vec_crypto) || !crypto_simd_usable()) + return crc32c_le_base(crc, p, len); + + if ((unsigned long)p & VMX_ALIGN_MASK) { + prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK); + crc = crc32c_le_base(crc, p, prealign); + len -= prealign; + p += prealign; + } + + if (len & ~VMX_ALIGN_MASK) { + preempt_disable(); + pagefault_disable(); + enable_kernel_altivec(); + crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK); + disable_kernel_altivec(); + pagefault_enable(); + preempt_enable(); + } + + tail = len & VMX_ALIGN_MASK; + if (tail) { + p += len & ~VMX_ALIGN_MASK; + crc = crc32c_le_base(crc, p, tail); + } + + return crc; +} +EXPORT_SYMBOL(crc32c_le_arch); + +u32 crc32_be_arch(u32 crc, const u8 *p, size_t len) +{ + return crc32_be_base(crc, p, len); +} +EXPORT_SYMBOL(crc32_be_arch); + +static int __init crc32_powerpc_init(void) +{ + if (cpu_has_feature(CPU_FTR_ARCH_207S) && + (cur_cpu_spec->cpu_user_features2 & PPC_FEATURE2_VEC_CRYPTO)) + static_branch_enable(&have_vec_crypto); + return 0; +} +arch_initcall(crc32_powerpc_init); + +static void __exit crc32_powerpc_exit(void) +{ +} +module_exit(crc32_powerpc_exit); + +u32 crc32_optimizations(void) +{ + if (static_key_enabled(&have_vec_crypto)) + return CRC32C_OPTIMIZATION; + return 0; +} +EXPORT_SYMBOL(crc32_optimizations); + +MODULE_AUTHOR("Anton Blanchard "); +MODULE_DESCRIPTION("CRC32C using vector polynomial multiply-sum instructions"); +MODULE_LICENSE("GPL"); diff --git a/arch/powerpc/crypto/crc32-vpmsum_core.S b/arch/powerpc/lib/crc32-vpmsum_core.S similarity index 100% rename from arch/powerpc/crypto/crc32-vpmsum_core.S rename to arch/powerpc/lib/crc32-vpmsum_core.S diff --git a/arch/powerpc/crypto/crc32c-vpmsum_asm.S b/arch/powerpc/lib/crc32c-vpmsum_asm.S similarity index 100% rename from arch/powerpc/crypto/crc32c-vpmsum_asm.S rename to arch/powerpc/lib/crc32c-vpmsum_asm.S