mirror of https://github.com/torvalds/linux.git
97 lines
3.5 KiB
C
97 lines
3.5 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
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/*
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* SHA-256 optimized for x86_64
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*
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* Copyright 2025 Google LLC
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*/
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#include <asm/fpu/api.h>
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#include <crypto/internal/simd.h>
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#include <linux/static_call.h>
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static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_sha_ni);
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DEFINE_STATIC_CALL(sha256_blocks_x86, sha256_blocks_generic);
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#define DEFINE_X86_SHA256_FN(c_fn, asm_fn) \
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asmlinkage void asm_fn(struct sha256_block_state *state, \
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const u8 *data, size_t nblocks); \
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static void c_fn(struct sha256_block_state *state, const u8 *data, \
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size_t nblocks) \
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{ \
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if (likely(crypto_simd_usable())) { \
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kernel_fpu_begin(); \
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asm_fn(state, data, nblocks); \
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kernel_fpu_end(); \
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} else { \
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sha256_blocks_generic(state, data, nblocks); \
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} \
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}
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DEFINE_X86_SHA256_FN(sha256_blocks_ssse3, sha256_transform_ssse3);
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DEFINE_X86_SHA256_FN(sha256_blocks_avx, sha256_transform_avx);
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DEFINE_X86_SHA256_FN(sha256_blocks_avx2, sha256_transform_rorx);
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DEFINE_X86_SHA256_FN(sha256_blocks_ni, sha256_ni_transform);
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static void sha256_blocks(struct sha256_block_state *state,
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const u8 *data, size_t nblocks)
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{
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static_call(sha256_blocks_x86)(state, data, nblocks);
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}
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static_assert(offsetof(struct __sha256_ctx, state) == 0);
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static_assert(offsetof(struct __sha256_ctx, bytecount) == 32);
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static_assert(offsetof(struct __sha256_ctx, buf) == 40);
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asmlinkage void sha256_ni_finup2x(const struct __sha256_ctx *ctx,
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const u8 *data1, const u8 *data2, int len,
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u8 out1[SHA256_DIGEST_SIZE],
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u8 out2[SHA256_DIGEST_SIZE]);
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#define sha256_finup_2x_arch sha256_finup_2x_arch
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static bool sha256_finup_2x_arch(const struct __sha256_ctx *ctx,
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const u8 *data1, const u8 *data2, size_t len,
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u8 out1[SHA256_DIGEST_SIZE],
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u8 out2[SHA256_DIGEST_SIZE])
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{
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/*
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* The assembly requires len >= SHA256_BLOCK_SIZE && len <= INT_MAX.
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* Further limit len to 65536 to avoid spending too long with preemption
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* disabled. (Of course, in practice len is nearly always 4096 anyway.)
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*/
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if (static_branch_likely(&have_sha_ni) && len >= SHA256_BLOCK_SIZE &&
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len <= 65536 && likely(irq_fpu_usable())) {
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kernel_fpu_begin();
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sha256_ni_finup2x(ctx, data1, data2, len, out1, out2);
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kernel_fpu_end();
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kmsan_unpoison_memory(out1, SHA256_DIGEST_SIZE);
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kmsan_unpoison_memory(out2, SHA256_DIGEST_SIZE);
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return true;
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}
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return false;
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}
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static bool sha256_finup_2x_is_optimized_arch(void)
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{
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return static_key_enabled(&have_sha_ni);
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}
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#define sha256_mod_init_arch sha256_mod_init_arch
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static inline void sha256_mod_init_arch(void)
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{
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if (boot_cpu_has(X86_FEATURE_SHA_NI)) {
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static_call_update(sha256_blocks_x86, sha256_blocks_ni);
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static_branch_enable(&have_sha_ni);
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} else if (cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM,
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NULL) &&
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boot_cpu_has(X86_FEATURE_AVX)) {
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if (boot_cpu_has(X86_FEATURE_AVX2) &&
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boot_cpu_has(X86_FEATURE_BMI2))
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static_call_update(sha256_blocks_x86,
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sha256_blocks_avx2);
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else
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static_call_update(sha256_blocks_x86,
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sha256_blocks_avx);
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} else if (boot_cpu_has(X86_FEATURE_SSSE3)) {
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static_call_update(sha256_blocks_x86, sha256_blocks_ssse3);
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}
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}
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