[PATCH v2] crypto/ahash: Require export/import in ahash

[Kamil Konieczny <k.konieczny@partner.samsung.com>]

Export and import were optional in async hash. As most drivers were
rewritten, they become mandatory now, so correct init of ahash
transformation.

Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
---
This is resend of previous patch. As Bartlomiej Zolnierkiewicz pointed out,
there are still three crypto drivers that didn't have export/import implemented:

drivers/crypto/mxs-dcp.c
drivers/crypto/n2_core.c
drivers/crypto/ux500/hash/hash_core.c

I have no documentation for them, so I sended patches with the behaviour taken
from crypto framework, but maybe that hardware is capable of import/export,
so proper implementation is possible. Unfortunatly, there is no maintainer
for any of these files.

Please take this patch after these remainig drivers will be patched.

 crypto/ahash.c | 18 ++----------------
 1 file changed, 2 insertions(+), 16 deletions(-)

diff --git a/crypto/ahash.c b/crypto/ahash.c
index 3a35d67de7d9..7a8906d5af53 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -434,16 +434,6 @@ static int ahash_def_finup(struct ahash_request *req)
 	return ahash_def_finup_finish1(req, err);
 }
 
-static int ahash_no_export(struct ahash_request *req, void *out)
-{
-	return -ENOSYS;
-}
-
-static int ahash_no_import(struct ahash_request *req, const void *in)
-{
-	return -ENOSYS;
-}
-
 static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 {
 	struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
@@ -451,8 +441,8 @@ static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 
 	hash->setkey = ahash_nosetkey;
 	hash->has_setkey = false;
-	hash->export = ahash_no_export;
-	hash->import = ahash_no_import;
+	hash->export = alg->export;
+	hash->import = alg->import;
 
 	if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
 		return crypto_init_shash_ops_async(tfm);
@@ -467,10 +457,6 @@ static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 		hash->setkey = alg->setkey;
 		hash->has_setkey = true;
 	}
-	if (alg->export)
-		hash->export = alg->export;
-	if (alg->import)
-		hash->import = alg->import;
 
 	return 0;
 }
-- 
2.15.0