xref: /linux/lib/crypto/x86/sha256.h (revision a1848f6e382145e0200843549f24f5af4b5c8136)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * SHA-256 optimized for x86_64
4  *
5  * Copyright 2025 Google LLC
6  */
7 #include <asm/fpu/api.h>
8 #include <linux/static_call.h>
9 
10 DEFINE_STATIC_CALL(sha256_blocks_x86, sha256_blocks_generic);
11 
12 #define DEFINE_X86_SHA256_FN(c_fn, asm_fn)                                 \
13 	asmlinkage void asm_fn(struct sha256_block_state *state,           \
14 			       const u8 *data, size_t nblocks);            \
15 	static void c_fn(struct sha256_block_state *state, const u8 *data, \
16 			 size_t nblocks)                                   \
17 	{                                                                  \
18 		if (likely(irq_fpu_usable())) {                            \
19 			kernel_fpu_begin();                                \
20 			asm_fn(state, data, nblocks);                      \
21 			kernel_fpu_end();                                  \
22 		} else {                                                   \
23 			sha256_blocks_generic(state, data, nblocks);       \
24 		}                                                          \
25 	}
26 
27 DEFINE_X86_SHA256_FN(sha256_blocks_ssse3, sha256_transform_ssse3);
28 DEFINE_X86_SHA256_FN(sha256_blocks_avx, sha256_transform_avx);
29 DEFINE_X86_SHA256_FN(sha256_blocks_avx2, sha256_transform_rorx);
30 DEFINE_X86_SHA256_FN(sha256_blocks_ni, sha256_ni_transform);
31 
32 static void sha256_blocks(struct sha256_block_state *state,
33 			  const u8 *data, size_t nblocks)
34 {
35 	static_call(sha256_blocks_x86)(state, data, nblocks);
36 }
37 
38 #define sha256_mod_init_arch sha256_mod_init_arch
39 static inline void sha256_mod_init_arch(void)
40 {
41 	if (boot_cpu_has(X86_FEATURE_SHA_NI)) {
42 		static_call_update(sha256_blocks_x86, sha256_blocks_ni);
43 	} else if (cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM,
44 				     NULL) &&
45 		   boot_cpu_has(X86_FEATURE_AVX)) {
46 		if (boot_cpu_has(X86_FEATURE_AVX2) &&
47 		    boot_cpu_has(X86_FEATURE_BMI2))
48 			static_call_update(sha256_blocks_x86,
49 					   sha256_blocks_avx2);
50 		else
51 			static_call_update(sha256_blocks_x86,
52 					   sha256_blocks_avx);
53 	} else if (boot_cpu_has(X86_FEATURE_SSSE3)) {
54 		static_call_update(sha256_blocks_x86, sha256_blocks_ssse3);
55 	}
56 }
57