[CRYPTO] api: Add type-safe spawns

This patch allows spawns of specific types (e.g., cipher) to be allocated.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 5 insertions, 4 deletions

diff --git a/crypto/hmac.c b/crypto/hmac.c
index b521bcd2b2c6..44187c5ee593 100644
--- a/crypto/hmac.c
+++ b/crypto/hmac.c
@@ -172,15 +172,16 @@ static int hmac_digest(struct hash_desc *pdesc, struct scatterlist *sg,
 
 static int hmac_init_tfm(struct crypto_tfm *tfm)
 {
+        struct crypto_hash *hash;
         struct crypto_instance *inst = (void *)tfm->__crt_alg;
         struct crypto_spawn *spawn = crypto_instance_ctx(inst);
         struct hmac_ctx *ctx = hmac_ctx(__crypto_hash_cast(tfm));
 
-        tfm = crypto_spawn_tfm(spawn);
-        if (IS_ERR(tfm))
-                return PTR_ERR(tfm);
+        hash = crypto_spawn_hash(spawn);
+        if (IS_ERR(hash))
+                return PTR_ERR(hash);
 
-        ctx->child = crypto_hash_cast(tfm);
+        ctx->child = hash;
         return 0;
 }