[CRYPTO] api: Added cra_init/cra_exit

This patch adds the hooks cra_init/cra_exit which are called during a tfm's
construction and destruction respectively.  This will be used by the instances
to allocate child tfm's.

For now this lets us get rid of the coa_init/coa_exit functions which are
used for exactly that purpose (unlike the dia_init function which is called
for each transaction).

In fact the coa_exit path is currently buggy as it may get called twice
when an error is encountered during initialisation.

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

crypto/api.c

@@ -188,13 +188,16 @@ struct crypto_tfm *crypto_alloc_tfm(const char *name, u32 flags)
 	if (crypto_init_flags(tfm, flags))
 		goto out_free_tfm;
 		
-	if (crypto_init_ops(tfm)) {
-		crypto_exit_ops(tfm);
+	if (crypto_init_ops(tfm))
 		goto out_free_tfm;
-	}
+
+	if (alg->cra_init && alg->cra_init(tfm))
+		goto cra_init_failed;
 
 	goto out;
 
+cra_init_failed:
+	crypto_exit_ops(tfm);
 out_free_tfm:
 	kfree(tfm);
 	tfm = NULL;
@@ -215,6 +218,8 @@ void crypto_free_tfm(struct crypto_tfm *tfm)
 	alg = tfm->__crt_alg;
 	size = sizeof(*tfm) + alg->cra_ctxsize;
 
+	if (alg->cra_exit)
+		alg->cra_exit(tfm);
 	crypto_exit_ops(tfm);
 	crypto_alg_put(alg);
 	memset(tfm, 0, size);

crypto/compress.c

@@ -41,21 +41,14 @@ int crypto_init_compress_flags(struct crypto_tfm *tfm, u32 flags)
 
 int crypto_init_compress_ops(struct crypto_tfm *tfm)
 {
-	int ret = 0;
 	struct compress_tfm *ops = &tfm->crt_compress;
-	
-	ret = tfm->__crt_alg->cra_compress.coa_init(tfm);
-	if (ret)
-		goto out;
 
 	ops->cot_compress = crypto_compress;
 	ops->cot_decompress = crypto_decompress;
 	
-out:
-	return ret;
+	return 0;
 }
 
 void crypto_exit_compress_ops(struct crypto_tfm *tfm)
 {
-	tfm->__crt_alg->cra_compress.coa_exit(tfm);
 }

crypto/deflate.c

@@ -201,9 +201,9 @@ static struct crypto_alg alg = {
 	.cra_ctxsize		= sizeof(struct deflate_ctx),
 	.cra_module		= THIS_MODULE,
 	.cra_list		= LIST_HEAD_INIT(alg.cra_list),
+	.cra_init		= deflate_init,
+	.cra_exit		= deflate_exit,
 	.cra_u			= { .compress = {
-	.coa_init		= deflate_init,
-	.coa_exit		= deflate_exit,
 	.coa_compress 		= deflate_compress,
 	.coa_decompress  	= deflate_decompress } }
 };

include/linux/crypto.h

@@ -109,8 +109,6 @@ struct digest_alg {
 };
 
 struct compress_alg {
-	int (*coa_init)(struct crypto_tfm *tfm);
-	void (*coa_exit)(struct crypto_tfm *tfm);
 	int (*coa_compress)(struct crypto_tfm *tfm, const u8 *src,
 			    unsigned int slen, u8 *dst, unsigned int *dlen);
 	int (*coa_decompress)(struct crypto_tfm *tfm, const u8 *src,
@@ -138,6 +136,9 @@ struct crypto_alg {
 		struct digest_alg digest;
 		struct compress_alg compress;
 	} cra_u;
+
+	int (*cra_init)(struct crypto_tfm *tfm);
+	void (*cra_exit)(struct crypto_tfm *tfm);
 	
 	struct module *cra_module;
 };