diff options
Diffstat (limited to 'arch/arm64/crypto/crc32-arm64.c')
| -rw-r--r-- | arch/arm64/crypto/crc32-arm64.c | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/arch/arm64/crypto/crc32-arm64.c b/arch/arm64/crypto/crc32-arm64.c new file mode 100644 index 000000000000..9499199924ae --- /dev/null +++ b/arch/arm64/crypto/crc32-arm64.c @@ -0,0 +1,274 @@ +/* + * 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); |