crypto: x86/sha256 - implement ->digest for sha256

Implement a ->digest function for sha256-ssse3, sha256-avx, sha256-avx2,
and sha256-ni.  This improves the performance of crypto_shash_digest()
with these algorithms by reducing the number of indirect calls that are
made.

For now, don't bother with this for sha224, since sha224 is rarely used.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/x86/crypto/sha256_ssse3_glue.c

@@ -107,12 +107,20 @@ static int sha256_ssse3_final(struct shash_desc *desc, u8 *out)
 	return sha256_ssse3_finup(desc, NULL, 0, out);
 }
 
+static int sha256_ssse3_digest(struct shash_desc *desc, const u8 *data,
+	      unsigned int len, u8 *out)
+{
+	return sha256_base_init(desc) ?:
+	       sha256_ssse3_finup(desc, data, len, out);
+}
+
 static struct shash_alg sha256_ssse3_algs[] = { {
 	.digestsize	=	SHA256_DIGEST_SIZE,
 	.init		=	sha256_base_init,
 	.update		=	sha256_ssse3_update,
 	.final		=	sha256_ssse3_final,
 	.finup		=	sha256_ssse3_finup,
+	.digest		=	sha256_ssse3_digest,
 	.descsize	=	sizeof(struct sha256_state),
 	.base		=	{
 		.cra_name	=	"sha256",
@@ -172,12 +180,20 @@ static int sha256_avx_final(struct shash_desc *desc, u8 *out)
 	return sha256_avx_finup(desc, NULL, 0, out);
 }
 
+static int sha256_avx_digest(struct shash_desc *desc, const u8 *data,
+		      unsigned int len, u8 *out)
+{
+	return sha256_base_init(desc) ?:
+	       sha256_avx_finup(desc, data, len, out);
+}
+
 static struct shash_alg sha256_avx_algs[] = { {
 	.digestsize	=	SHA256_DIGEST_SIZE,
 	.init		=	sha256_base_init,
 	.update		=	sha256_avx_update,
 	.final		=	sha256_avx_final,
 	.finup		=	sha256_avx_finup,
+	.digest		=	sha256_avx_digest,
 	.descsize	=	sizeof(struct sha256_state),
 	.base		=	{
 		.cra_name	=	"sha256",
@@ -248,12 +264,20 @@ static int sha256_avx2_final(struct shash_desc *desc, u8 *out)
 	return sha256_avx2_finup(desc, NULL, 0, out);
 }
 
+static int sha256_avx2_digest(struct shash_desc *desc, const u8 *data,
+		      unsigned int len, u8 *out)
+{
+	return sha256_base_init(desc) ?:
+	       sha256_avx2_finup(desc, data, len, out);
+}
+
 static struct shash_alg sha256_avx2_algs[] = { {
 	.digestsize	=	SHA256_DIGEST_SIZE,
 	.init		=	sha256_base_init,
 	.update		=	sha256_avx2_update,
 	.final		=	sha256_avx2_final,
 	.finup		=	sha256_avx2_finup,
+	.digest		=	sha256_avx2_digest,
 	.descsize	=	sizeof(struct sha256_state),
 	.base		=	{
 		.cra_name	=	"sha256",
@@ -323,12 +347,20 @@ static int sha256_ni_final(struct shash_desc *desc, u8 *out)
 	return sha256_ni_finup(desc, NULL, 0, out);
 }
 
+static int sha256_ni_digest(struct shash_desc *desc, const u8 *data,
+		      unsigned int len, u8 *out)
+{
+	return sha256_base_init(desc) ?:
+	       sha256_ni_finup(desc, data, len, out);
+}
+
 static struct shash_alg sha256_ni_algs[] = { {
 	.digestsize	=	SHA256_DIGEST_SIZE,
 	.init		=	sha256_base_init,
 	.update		=	sha256_ni_update,
 	.final		=	sha256_ni_final,
 	.finup		=	sha256_ni_finup,
+	.digest		=	sha256_ni_digest,
 	.descsize	=	sizeof(struct sha256_state),
 	.base		=	{
 		.cra_name	=	"sha256",