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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-07-24 13:28:17 +0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2017-08-04 04:27:24 +0300 |
| commit | 3759ee057261a45da0505e79084de8b6ac31c4a5 (patch) | |
| tree | 70af3d5db93464c2e4b18051241225ffdd4d7139 /arch/arm/crypto/ghash-ce-glue.c | |
| parent | 537c1445ab0b1e33ca338b669e347652c45f4e8c (diff) | |
| download | linux-3759ee057261a45da0505e79084de8b6ac31c4a5.tar.xz | |
crypto: arm/ghash - add NEON accelerated fallback for vmull.p64
Implement a NEON fallback for systems that do support NEON but have
no support for the optional 64x64->128 polynomial multiplication
instruction that is part of the ARMv8 Crypto Extensions. It is based
on the paper "Fast Software Polynomial Multiplication on ARM Processors
Using the NEON Engine" by Danilo Camara, Conrado Gouvea, Julio Lopez and
Ricardo Dahab (https://hal.inria.fr/hal-01506572)
On a 32-bit guest executing under KVM on a Cortex-A57, the new code is
not only 4x faster than the generic table based GHASH driver, it is also
time invariant. (Note that the existing vmull.p64 code is 16x faster on
this core).
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'arch/arm/crypto/ghash-ce-glue.c')
| -rw-r--r-- | arch/arm/crypto/ghash-ce-glue.c | 24 |
1 files changed, 21 insertions, 3 deletions
diff --git a/arch/arm/crypto/ghash-ce-glue.c b/arch/arm/crypto/ghash-ce-glue.c index 6bac8bea9f1e..d9bb52cae2ac 100644 --- a/arch/arm/crypto/ghash-ce-glue.c +++ b/arch/arm/crypto/ghash-ce-glue.c @@ -22,6 +22,7 @@ MODULE_DESCRIPTION("GHASH secure hash using ARMv8 Crypto Extensions"); MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_CRYPTO("ghash"); #define GHASH_BLOCK_SIZE 16 #define GHASH_DIGEST_SIZE 16 @@ -41,8 +42,17 @@ struct ghash_async_ctx { struct cryptd_ahash *cryptd_tfm; }; -asmlinkage void pmull_ghash_update(int blocks, u64 dg[], const char *src, - struct ghash_key const *k, const char *head); +asmlinkage void pmull_ghash_update_p64(int blocks, u64 dg[], const char *src, + struct ghash_key const *k, + const char *head); + +asmlinkage void pmull_ghash_update_p8(int blocks, u64 dg[], const char *src, + struct ghash_key const *k, + const char *head); + +static void (*pmull_ghash_update)(int blocks, u64 dg[], const char *src, + struct ghash_key const *k, + const char *head); static int ghash_init(struct shash_desc *desc) { @@ -312,6 +322,14 @@ static int __init ghash_ce_mod_init(void) { int err; + if (!(elf_hwcap & HWCAP_NEON)) + return -ENODEV; + + if (elf_hwcap2 & HWCAP2_PMULL) + pmull_ghash_update = pmull_ghash_update_p64; + else + pmull_ghash_update = pmull_ghash_update_p8; + err = crypto_register_shash(&ghash_alg); if (err) return err; @@ -332,5 +350,5 @@ static void __exit ghash_ce_mod_exit(void) crypto_unregister_shash(&ghash_alg); } -module_cpu_feature_match(PMULL, ghash_ce_mod_init); +module_init(ghash_ce_mod_init); module_exit(ghash_ce_mod_exit); |