path: root/include/crypto
diff options
authorEric Biggers <ebiggers@google.com>2019-03-12 22:12:47 -0700
committerHerbert Xu <herbert@gondor.apana.org.au>2019-03-22 20:57:27 +0800
commitb55e1a39543f5e9aadf1149f8ad4bcff5cace8a4 (patch)
tree9f50f2eee2a2e57fe689f899ff572f097feab054 /include/crypto
parent580e295178402d14bbf598a5702f8e01fc59dbaa (diff)
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')
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 @@
+#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.
+ */
+DECLARE_PER_CPU(bool, crypto_simd_disabled_for_test);
+#define crypto_simd_usable() \
+ (may_use_simd() && !this_cpu_read(crypto_simd_disabled_for_test))
+#define crypto_simd_usable() may_use_simd()