crypto: shash - Add spawn support

This patch adds the functions needed to create and use shash
spawns, i.e., to use shash algorithms in a template.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/shash.c

@@ -509,5 +509,14 @@ void shash_free_instance(struct crypto_instance *inst)
 }
 EXPORT_SYMBOL_GPL(shash_free_instance);
 
+int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
+			    struct shash_alg *alg,
+			    struct crypto_instance *inst)
+{
+	return crypto_init_spawn2(&spawn->base, &alg->base, inst,
+				  &crypto_shash_type);
+}
+EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Synchronous cryptographic hash type");

include/crypto/internal/hash.h

@@ -38,6 +38,10 @@ struct shash_instance {
 	struct shash_alg alg;
 };
 
+struct crypto_shash_spawn {
+	struct crypto_spawn base;
+};
+
 extern const struct crypto_type crypto_ahash_type;
 
 int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err);
@@ -52,6 +56,10 @@ int crypto_unregister_shash(struct shash_alg *alg);
 
 void shash_free_instance(struct crypto_instance *inst);
 
+int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
+			    struct shash_alg *alg,
+			    struct crypto_instance *inst);
+
 static inline void *crypto_ahash_ctx(struct crypto_ahash *tfm)
 {
 	return crypto_tfm_ctx(&tfm->base);
@@ -106,5 +114,11 @@ static inline struct shash_instance *shash_alloc_instance(
 				      sizeof(struct shash_alg) - sizeof(*alg));
 }
 
+static inline struct crypto_shash *crypto_spawn_shash(
+	struct crypto_shash_spawn *spawn)
+{
+	return crypto_spawn_tfm2(&spawn->base);
+}
+
 #endif	/* _CRYPTO_INTERNAL_HASH_H */