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| author | Eric Biggers <ebiggers@google.com> | 2019-03-12 22:12:47 -0700 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2019-03-22 20:57:27 +0800 |
| commit | b55e1a39543f5e9aadf1149f8ad4bcff5cace8a4 (patch) | |
| tree | 9f50f2eee2a2e57fe689f899ff572f097feab054 /include/crypto | |
| parent | 580e295178402d14bbf598a5702f8e01fc59dbaa (diff) | |
| download | lwn-b55e1a39543f5e9aadf1149f8ad4bcff5cace8a4.tar.gz lwn-b55e1a39543f5e9aadf1149f8ad4bcff5cace8a4.zip | |
crypto: simd,testmgr - introduce crypto_simd_usable()
So that the no-SIMD fallback code can be tested by the crypto
self-tests, add a macro crypto_simd_usable() which wraps may_use_simd(),
but also returns false if the crypto self-tests have set a per-CPU bool
to disable SIMD in crypto code on the current CPU.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'include/crypto')
| -rw-r--r-- | include/crypto/internal/simd.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/crypto/internal/simd.h b/include/crypto/internal/simd.h index a23b18b6ad61..d2316242a988 100644 --- a/include/crypto/internal/simd.h +++ b/include/crypto/internal/simd.h @@ -6,6 +6,9 @@ #ifndef _CRYPTO_INTERNAL_SIMD_H #define _CRYPTO_INTERNAL_SIMD_H +#include <linux/percpu.h> +#include <linux/types.h> + /* skcipher support */ struct simd_skcipher_alg; @@ -42,4 +45,25 @@ int simd_register_aeads_compat(struct aead_alg *algs, int count, void simd_unregister_aeads(struct aead_alg *algs, int count, struct simd_aead_alg **simd_algs); +/* + * crypto_simd_usable() - is it allowed at this time to use SIMD instructions or + * access the SIMD register file? + * + * This delegates to may_use_simd(), except that this also returns false if SIMD + * in crypto code has been temporarily disabled on this CPU by the crypto + * self-tests, in order to test the no-SIMD fallback code. This override is + * currently limited to configurations where the extra self-tests are enabled, + * because it might be a bit too invasive to be part of the regular self-tests. + * + * This is a macro so that <asm/simd.h>, which some architectures don't have, + * doesn't have to be included directly here. + */ +#ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS +DECLARE_PER_CPU(bool, crypto_simd_disabled_for_test); +#define crypto_simd_usable() \ + (may_use_simd() && !this_cpu_read(crypto_simd_disabled_for_test)) +#else +#define crypto_simd_usable() may_use_simd() +#endif + #endif /* _CRYPTO_INTERNAL_SIMD_H */ |