crypto: virtio - Drop superfluous ctx->tfm backpointer

struct virtio_crypto_[as]kcipher_ctx contains a backpointer to struct
crypto_[as]kcipher which is superfluous in two ways:

First, it's not used anywhere.  Second, the context is embedded into
struct crypto_tfm, so one could just use container_of() to get from the
context to crypto_tfm and from there to crypto_[as]kcipher.

Drop the superfluous backpointer.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Author: l1k

drivers/crypto/virtio/virtio_crypto_akcipher_algs.c

@@ -26,7 +26,6 @@ struct virtio_crypto_rsa_ctx {
 
 struct virtio_crypto_akcipher_ctx {
 	struct virtio_crypto *vcrypto;
-	struct crypto_akcipher *tfm;
 	bool session_valid;
 	__u64 session_id;
 	union {
@@ -447,10 +446,6 @@ static unsigned int virtio_crypto_rsa_max_size(struct crypto_akcipher *tfm)
 
 static int virtio_crypto_rsa_init_tfm(struct crypto_akcipher *tfm)
 {
-	struct virtio_crypto_akcipher_ctx *ctx = akcipher_tfm_ctx(tfm);
-
-	ctx->tfm = tfm;
-
 	akcipher_set_reqsize(tfm,
 			     sizeof(struct virtio_crypto_akcipher_request));
 

drivers/crypto/virtio/virtio_crypto_skcipher_algs.c

@@ -17,7 +17,6 @@
 
 struct virtio_crypto_skcipher_ctx {
 	struct virtio_crypto *vcrypto;
-	struct crypto_skcipher *tfm;
 
 	struct virtio_crypto_sym_session_info enc_sess_info;
 	struct virtio_crypto_sym_session_info dec_sess_info;
@@ -515,10 +514,7 @@ static int virtio_crypto_skcipher_decrypt(struct skcipher_request *req)
 
 static int virtio_crypto_skcipher_init(struct crypto_skcipher *tfm)
 {
-	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
-
 	crypto_skcipher_set_reqsize(tfm, sizeof(struct virtio_crypto_sym_request));
-	ctx->tfm = tfm;
 
 	return 0;
 }