crypto: ahash - make hash walk functions from ahash.c public

Make the hash walk functions
  crypto_hash_walk_done()
  crypto_hash_walk_first()
  crypto_hash_walk_last()
public again.
These functions had been removed from the header file
include/crypto/internal/hash.h with commit 7fa4817
("crypto: ahash - make hash walk functions private to ahash.c")
as there was no crypto algorithm code using them.

With the upcoming crypto implementation for s390 phmac
these functions will be exploited and thus need to be
public within the kernel again.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Author: hfreude

crypto/ahash.c

@@ -29,19 +29,6 @@
 
 #define CRYPTO_ALG_TYPE_AHASH_MASK	0x0000000e
 
-struct crypto_hash_walk {
-	const char *data;
-
-	unsigned int offset;
-	unsigned int flags;
-
-	struct page *pg;
-	unsigned int entrylen;
-
-	unsigned int total;
-	struct scatterlist *sg;
-};
-
 static int ahash_def_finup(struct ahash_request *req);
 
 static inline bool crypto_ahash_block_only(struct crypto_ahash *tfm)
@@ -112,8 +99,8 @@ static int hash_walk_new_entry(struct crypto_hash_walk *walk)
 	return hash_walk_next(walk);
 }
 
-static int crypto_hash_walk_first(struct ahash_request *req,
-				  struct crypto_hash_walk *walk)
+int crypto_hash_walk_first(struct ahash_request *req,
+			   struct crypto_hash_walk *walk)
 {
 	walk->total = req->nbytes;
 	walk->entrylen = 0;
@@ -133,8 +120,9 @@ static int crypto_hash_walk_first(struct ahash_request *req,
 
 	return hash_walk_new_entry(walk);
 }
+EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
 
-static int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
+int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
 {
 	if ((walk->flags & CRYPTO_AHASH_REQ_VIRT))
 		return err;
@@ -160,11 +148,7 @@ static int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
 
 	return hash_walk_new_entry(walk);
 }
-
-static inline int crypto_hash_walk_last(struct crypto_hash_walk *walk)
-{
-	return !(walk->entrylen | walk->total);
-}
+EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
 
 /*
  * For an ahash tfm that is using an shash algorithm (instead of an ahash

include/crypto/internal/hash.h

@@ -30,6 +30,20 @@
                 __##name##_req, (req))
 
 struct ahash_request;
+struct scatterlist;
+
+struct crypto_hash_walk {
+	const char *data;
+
+	unsigned int offset;
+	unsigned int flags;
+
+	struct page *pg;
+	unsigned int entrylen;
+
+	unsigned int total;
+	struct scatterlist *sg;
+};
 
 struct ahash_instance {
 	void (*free)(struct ahash_instance *inst);
@@ -61,6 +75,15 @@ struct crypto_shash_spawn {
 	struct crypto_spawn base;
 };
 
+int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err);
+int crypto_hash_walk_first(struct ahash_request *req,
+			   struct crypto_hash_walk *walk);
+
+static inline int crypto_hash_walk_last(struct crypto_hash_walk *walk)
+{
+	return !(walk->entrylen | walk->total);
+}
+
 int crypto_register_ahash(struct ahash_alg *alg);
 void crypto_unregister_ahash(struct ahash_alg *alg);
 int crypto_register_ahashes(struct ahash_alg *algs, int count);