diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2018-09-27 01:49:19 +0200 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2018-10-02 03:41:49 +0200 |
| commit | 60bacab97d60b951347b3f100c17f64b408b8b59 (patch) | |
| tree | c1449a5f5ce8c44abda002d6e7a4ae487a671624 /src/crypto/zinc/chacha20/chacha20-arm-glue.h | |
| parent | 791c515a0da6020820786a63324db9af51896e33 (diff) | |
chacha20: feed fpu functions PAGE_SIZE at a time
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Diffstat (limited to 'src/crypto/zinc/chacha20/chacha20-arm-glue.h')
| -rw-r--r-- | src/crypto/zinc/chacha20/chacha20-arm-glue.h | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/src/crypto/zinc/chacha20/chacha20-arm-glue.h b/src/crypto/zinc/chacha20/chacha20-arm-glue.h index b8d9e12..881e16c 100644 --- a/src/crypto/zinc/chacha20/chacha20-arm-glue.h +++ b/src/crypto/zinc/chacha20/chacha20-arm-glue.h @@ -38,16 +38,33 @@ static void __init chacha20_fpu_init(void) } static inline bool chacha20_arch(struct chacha20_ctx *state, u8 *dst, - const u8 *src, const size_t len, + const u8 *src, size_t len, simd_context_t *simd_context) { - if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && chacha20_use_neon && - len >= CHACHA20_BLOCK_SIZE * 3 && simd_use(simd_context)) - chacha20_neon(dst, src, len, state->key, state->counter); - else - chacha20_arm(dst, src, len, state->key, state->counter); + /* SIMD disables preemption, so relax after processing each page. */ + BUILD_BUG_ON(PAGE_SIZE < CHACHA20_BLOCK_SIZE || + PAGE_SIZE % CHACHA20_BLOCK_SIZE); + + for (;;) { + if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && chacha20_use_neon && + len >= CHACHA20_BLOCK_SIZE * 3 && simd_use(simd_context)) { + const size_t bytes = min_t(size_t, len, PAGE_SIZE); + + chacha20_neon(dst, src, bytes, state->key, state->counter); + state->counter[0] += (bytes + 63) / 64; + len -= bytes; + if (!len) + break; + dst += bytes; + src += bytes; + simd_relax(simd_context); + } else { + chacha20_arm(dst, src, len, state->key, state->counter); + state->counter[0] += (len + 63) / 64; + break; + } + } - state->counter[0] += (len + 63) / 64; return true; } |