Re: [RFT PATCH 1/3] crypto: s390/aes - convert to skcipher API

[Harald Freudenberger <freude@linux.ibm.com>]

On 12.10.19 22:18, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@google.com>
>
> Convert the glue code for the S390 CPACF implementations of AES-ECB,
> AES-CBC, AES-XTS, and AES-CTR from the deprecated "blkcipher" API to the
> "skcipher" API.  This is needed in order for the blkcipher API to be
> removed.
>
> Note: I made CTR use the same function for encryption and decryption,
> since CTR encryption and decryption are identical.
>
> Signed-off-by: Eric Biggers <ebiggers@google.com>
> ---
>  arch/s390/crypto/aes_s390.c | 609 ++++++++++++++----------------------
>  1 file changed, 234 insertions(+), 375 deletions(-)
>
> diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
> index 9803e96d2924..ead0b2c9881d 100644
> --- a/arch/s390/crypto/aes_s390.c
> +++ b/arch/s390/crypto/aes_s390.c
> @@ -44,7 +44,7 @@ struct s390_aes_ctx {
>  	int key_len;
>  	unsigned long fc;
>  	union {
> -		struct crypto_sync_skcipher *blk;
> +		struct crypto_skcipher *skcipher;
>  		struct crypto_cipher *cip;
>  	} fallback;
>  };
> @@ -54,7 +54,7 @@ struct s390_xts_ctx {
>  	u8 pcc_key[32];
>  	int key_len;
>  	unsigned long fc;
> -	struct crypto_sync_skcipher *fallback;
> +	struct crypto_skcipher *fallback;
>  };
>  
>  struct gcm_sg_walk {
> @@ -178,66 +178,41 @@ static struct crypto_alg aes_alg = {
>  	}
>  };
>  
> -static int setkey_fallback_blk(struct crypto_tfm *tfm, const u8 *key,
> -		unsigned int len)
> +static int setkey_fallback_skcipher(struct crypto_skcipher *tfm, const u8 *key,
> +				    unsigned int len)
>  {
> -	struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
> -	unsigned int ret;
> -
> -	crypto_sync_skcipher_clear_flags(sctx->fallback.blk,
> -					 CRYPTO_TFM_REQ_MASK);
> -	crypto_sync_skcipher_set_flags(sctx->fallback.blk, tfm->crt_flags &
> -						      CRYPTO_TFM_REQ_MASK);
> -
> -	ret = crypto_sync_skcipher_setkey(sctx->fallback.blk, key, len);
> -
> -	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
> -	tfm->crt_flags |= crypto_sync_skcipher_get_flags(sctx->fallback.blk) &
> -			  CRYPTO_TFM_RES_MASK;
> -
> -	return ret;
> -}
> -
> -static int fallback_blk_dec(struct blkcipher_desc *desc,
> -		struct scatterlist *dst, struct scatterlist *src,
> -		unsigned int nbytes)
> -{
> -	unsigned int ret;
> -	struct crypto_blkcipher *tfm = desc->tfm;
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(tfm);
> -	SYNC_SKCIPHER_REQUEST_ON_STACK(req, sctx->fallback.blk);
> -
> -	skcipher_request_set_sync_tfm(req, sctx->fallback.blk);
> -	skcipher_request_set_callback(req, desc->flags, NULL, NULL);
> -	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
> -
> -	ret = crypto_skcipher_decrypt(req);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
> +	int ret;
>  
> -	skcipher_request_zero(req);
> +	crypto_skcipher_clear_flags(sctx->fallback.skcipher,
> +				    CRYPTO_TFM_REQ_MASK);
> +	crypto_skcipher_set_flags(sctx->fallback.skcipher,
> +				  crypto_skcipher_get_flags(tfm) &
> +				  CRYPTO_TFM_REQ_MASK);
> +	ret = crypto_skcipher_setkey(sctx->fallback.skcipher, key, len);
> +	crypto_skcipher_set_flags(tfm,
> +				  crypto_skcipher_get_flags(sctx->fallback.skcipher) &
> +				  CRYPTO_TFM_RES_MASK);
>  	return ret;
>  }
>  
> -static int fallback_blk_enc(struct blkcipher_desc *desc,
> -		struct scatterlist *dst, struct scatterlist *src,
> -		unsigned int nbytes)
> +static int fallback_skcipher_crypt(struct s390_aes_ctx *sctx,
> +				   struct skcipher_request *req,
> +				   unsigned long modifier)
>  {
> -	unsigned int ret;
> -	struct crypto_blkcipher *tfm = desc->tfm;
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(tfm);
> -	SYNC_SKCIPHER_REQUEST_ON_STACK(req, sctx->fallback.blk);
> -
> -	skcipher_request_set_sync_tfm(req, sctx->fallback.blk);
> -	skcipher_request_set_callback(req, desc->flags, NULL, NULL);
> -	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
> +	struct skcipher_request *subreq = skcipher_request_ctx(req);
>  
> -	ret = crypto_skcipher_encrypt(req);
> -	return ret;
> +	*subreq = *req;
> +	skcipher_request_set_tfm(subreq, sctx->fallback.skcipher);
> +	return (modifier & CPACF_DECRYPT) ?
> +		crypto_skcipher_decrypt(subreq) :
> +		crypto_skcipher_encrypt(subreq);
>  }
>  
> -static int ecb_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
> +static int ecb_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
>  			   unsigned int key_len)
>  {
> -	struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
>  	unsigned long fc;
>  
>  	/* Pick the correct function code based on the key length */
> @@ -248,111 +223,92 @@ static int ecb_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
>  	/* Check if the function code is available */
>  	sctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0;
>  	if (!sctx->fc)
> -		return setkey_fallback_blk(tfm, in_key, key_len);
> +		return setkey_fallback_skcipher(tfm, in_key, key_len);
>  
>  	sctx->key_len = key_len;
>  	memcpy(sctx->key, in_key, key_len);
>  	return 0;
>  }
>  
> -static int ecb_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
> -			 struct blkcipher_walk *walk)
> +static int ecb_aes_crypt(struct skcipher_request *req, unsigned long modifier)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> +	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
> +	struct skcipher_walk walk;
>  	unsigned int nbytes, n;
>  	int ret;
>  
> -	ret = blkcipher_walk_virt(desc, walk);
> -	while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
> +	if (unlikely(!sctx->fc))
> +		return fallback_skcipher_crypt(sctx, req, modifier);
> +
> +	ret = skcipher_walk_virt(&walk, req, false);
> +	while ((nbytes = walk.nbytes) != 0) {
>  		/* only use complete blocks */
>  		n = nbytes & ~(AES_BLOCK_SIZE - 1);
>  		cpacf_km(sctx->fc | modifier, sctx->key,
> -			 walk->dst.virt.addr, walk->src.virt.addr, n);
> -		ret = blkcipher_walk_done(desc, walk, nbytes - n);
> +			 walk.dst.virt.addr, walk.src.virt.addr, n);
> +		ret = skcipher_walk_done(&walk, nbytes - n);
>  	}
> -
>  	return ret;
>  }
>  
> -static int ecb_aes_encrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> +static int ecb_aes_encrypt(struct skcipher_request *req)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (unlikely(!sctx->fc))
> -		return fallback_blk_enc(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return ecb_aes_crypt(desc, 0, &walk);
> +	return ecb_aes_crypt(req, 0);
>  }
>  
> -static int ecb_aes_decrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> +static int ecb_aes_decrypt(struct skcipher_request *req)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (unlikely(!sctx->fc))
> -		return fallback_blk_dec(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return ecb_aes_crypt(desc, CPACF_DECRYPT, &walk);
> +	return ecb_aes_crypt(req, CPACF_DECRYPT);
>  }
>  
> -static int fallback_init_blk(struct crypto_tfm *tfm)
> +static int fallback_init_skcipher(struct crypto_skcipher *tfm)
>  {
> -	const char *name = tfm->__crt_alg->cra_name;
> -	struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
> +	const char *name = crypto_tfm_alg_name(&tfm->base);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
>  
> -	sctx->fallback.blk = crypto_alloc_sync_skcipher(name, 0,
> -						   CRYPTO_ALG_NEED_FALLBACK);
> +	sctx->fallback.skcipher = crypto_alloc_skcipher(name, 0,
> +				CRYPTO_ALG_NEED_FALLBACK | CRYPTO_ALG_ASYNC);
>  
> -	if (IS_ERR(sctx->fallback.blk)) {
> +	if (IS_ERR(sctx->fallback.skcipher)) {
>  		pr_err("Allocating AES fallback algorithm %s failed\n",
>  		       name);
> -		return PTR_ERR(sctx->fallback.blk);
> +		return PTR_ERR(sctx->fallback.skcipher);
>  	}
>  
> +	crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
> +				    crypto_skcipher_reqsize(sctx->fallback.skcipher));
>  	return 0;
>  }
>  
> -static void fallback_exit_blk(struct crypto_tfm *tfm)
> +static void fallback_exit_skcipher(struct crypto_skcipher *tfm)
>  {
> -	struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
>  
> -	crypto_free_sync_skcipher(sctx->fallback.blk);
> +	crypto_free_skcipher(sctx->fallback.skcipher);
>  }
>  
> -static struct crypto_alg ecb_aes_alg = {
> -	.cra_name		=	"ecb(aes)",
> -	.cra_driver_name	=	"ecb-aes-s390",
> -	.cra_priority		=	401,	/* combo: aes + ecb + 1 */
> -	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER |
> -					CRYPTO_ALG_NEED_FALLBACK,
> -	.cra_blocksize		=	AES_BLOCK_SIZE,
> -	.cra_ctxsize		=	sizeof(struct s390_aes_ctx),
> -	.cra_type		=	&crypto_blkcipher_type,
> -	.cra_module		=	THIS_MODULE,
> -	.cra_init		=	fallback_init_blk,
> -	.cra_exit		=	fallback_exit_blk,
> -	.cra_u			=	{
> -		.blkcipher = {
> -			.min_keysize		=	AES_MIN_KEY_SIZE,
> -			.max_keysize		=	AES_MAX_KEY_SIZE,
> -			.setkey			=	ecb_aes_set_key,
> -			.encrypt		=	ecb_aes_encrypt,
> -			.decrypt		=	ecb_aes_decrypt,
> -		}
> -	}
> +static struct skcipher_alg ecb_aes_alg = {
> +	.base.cra_name		=	"ecb(aes)",
> +	.base.cra_driver_name	=	"ecb-aes-s390",
> +	.base.cra_priority	=	401,	/* combo: aes + ecb + 1 */
> +	.base.cra_flags		=	CRYPTO_ALG_NEED_FALLBACK,
> +	.base.cra_blocksize	=	AES_BLOCK_SIZE,
> +	.base.cra_ctxsize	=	sizeof(struct s390_aes_ctx),
> +	.base.cra_module	=	THIS_MODULE,
> +	.init			=	fallback_init_skcipher,
> +	.exit			=	fallback_exit_skcipher,
> +	.min_keysize		=	AES_MIN_KEY_SIZE,
> +	.max_keysize		=	AES_MAX_KEY_SIZE,
> +	.setkey			=	ecb_aes_set_key,
> +	.encrypt		=	ecb_aes_encrypt,
> +	.decrypt		=	ecb_aes_decrypt,
>  };
>  
> -static int cbc_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
> +static int cbc_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
>  			   unsigned int key_len)
>  {
> -	struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
>  	unsigned long fc;
>  
>  	/* Pick the correct function code based on the key length */
> @@ -363,17 +319,18 @@ static int cbc_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
>  	/* Check if the function code is available */
>  	sctx->fc = (fc && cpacf_test_func(&kmc_functions, fc)) ? fc : 0;
>  	if (!sctx->fc)
> -		return setkey_fallback_blk(tfm, in_key, key_len);
> +		return setkey_fallback_skcipher(tfm, in_key, key_len);
>  
>  	sctx->key_len = key_len;
>  	memcpy(sctx->key, in_key, key_len);
>  	return 0;
>  }
>  
> -static int cbc_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
> -			 struct blkcipher_walk *walk)
> +static int cbc_aes_crypt(struct skcipher_request *req, unsigned long modifier)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> +	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
> +	struct skcipher_walk walk;
>  	unsigned int nbytes, n;
>  	int ret;
>  	struct {
> @@ -381,134 +338,74 @@ static int cbc_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
>  		u8 key[AES_MAX_KEY_SIZE];
>  	} param;
>  
> -	ret = blkcipher_walk_virt(desc, walk);
> -	memcpy(param.iv, walk->iv, AES_BLOCK_SIZE);
> +	if (unlikely(!sctx->fc))
> +		return fallback_skcipher_crypt(sctx, req, modifier);
> +
> +	ret = skcipher_walk_virt(&walk, req, false);
> +	if (ret)
> +		return ret;
> +	memcpy(param.iv, walk.iv, AES_BLOCK_SIZE);
>  	memcpy(param.key, sctx->key, sctx->key_len);
> -	while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
> +	while ((nbytes = walk.nbytes) != 0) {
>  		/* only use complete blocks */
>  		n = nbytes & ~(AES_BLOCK_SIZE - 1);
>  		cpacf_kmc(sctx->fc | modifier, &param,
> -			  walk->dst.virt.addr, walk->src.virt.addr, n);
> -		ret = blkcipher_walk_done(desc, walk, nbytes - n);
> +			  walk.dst.virt.addr, walk.src.virt.addr, n);
> +		memcpy(walk.iv, param.iv, AES_BLOCK_SIZE);
> +		ret = skcipher_walk_done(&walk, nbytes - n);
>  	}
> -	memcpy(walk->iv, param.iv, AES_BLOCK_SIZE);
>  	return ret;
>  }
>  
> -static int cbc_aes_encrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> +static int cbc_aes_encrypt(struct skcipher_request *req)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (unlikely(!sctx->fc))
> -		return fallback_blk_enc(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return cbc_aes_crypt(desc, 0, &walk);
> +	return cbc_aes_crypt(req, 0);
>  }
>  
> -static int cbc_aes_decrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> +static int cbc_aes_decrypt(struct skcipher_request *req)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (unlikely(!sctx->fc))
> -		return fallback_blk_dec(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return cbc_aes_crypt(desc, CPACF_DECRYPT, &walk);
> +	return cbc_aes_crypt(req, CPACF_DECRYPT);
>  }
>  
> -static struct crypto_alg cbc_aes_alg = {
> -	.cra_name		=	"cbc(aes)",
> -	.cra_driver_name	=	"cbc-aes-s390",
> -	.cra_priority		=	402,	/* ecb-aes-s390 + 1 */
> -	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER |
> -					CRYPTO_ALG_NEED_FALLBACK,
> -	.cra_blocksize		=	AES_BLOCK_SIZE,
> -	.cra_ctxsize		=	sizeof(struct s390_aes_ctx),
> -	.cra_type		=	&crypto_blkcipher_type,
> -	.cra_module		=	THIS_MODULE,
> -	.cra_init		=	fallback_init_blk,
> -	.cra_exit		=	fallback_exit_blk,
> -	.cra_u			=	{
> -		.blkcipher = {
> -			.min_keysize		=	AES_MIN_KEY_SIZE,
> -			.max_keysize		=	AES_MAX_KEY_SIZE,
> -			.ivsize			=	AES_BLOCK_SIZE,
> -			.setkey			=	cbc_aes_set_key,
> -			.encrypt		=	cbc_aes_encrypt,
> -			.decrypt		=	cbc_aes_decrypt,
> -		}
> -	}
> +static struct skcipher_alg cbc_aes_alg = {
> +	.base.cra_name		=	"cbc(aes)",
> +	.base.cra_driver_name	=	"cbc-aes-s390",
> +	.base.cra_priority	=	402,	/* ecb-aes-s390 + 1 */
> +	.base.cra_flags		=	CRYPTO_ALG_NEED_FALLBACK,
> +	.base.cra_blocksize	=	AES_BLOCK_SIZE,
> +	.base.cra_ctxsize	=	sizeof(struct s390_aes_ctx),
> +	.base.cra_module	=	THIS_MODULE,
> +	.init			=	fallback_init_skcipher,
> +	.exit			=	fallback_exit_skcipher,
> +	.min_keysize		=	AES_MIN_KEY_SIZE,
> +	.max_keysize		=	AES_MAX_KEY_SIZE,
> +	.ivsize			=	AES_BLOCK_SIZE,
> +	.setkey			=	cbc_aes_set_key,
> +	.encrypt		=	cbc_aes_encrypt,
> +	.decrypt		=	cbc_aes_decrypt,
>  };
>  
> -static int xts_fallback_setkey(struct crypto_tfm *tfm, const u8 *key,
> -				   unsigned int len)
> -{
> -	struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
> -	unsigned int ret;
> -
> -	crypto_sync_skcipher_clear_flags(xts_ctx->fallback,
> -					 CRYPTO_TFM_REQ_MASK);
> -	crypto_sync_skcipher_set_flags(xts_ctx->fallback, tfm->crt_flags &
> -						     CRYPTO_TFM_REQ_MASK);
> -
> -	ret = crypto_sync_skcipher_setkey(xts_ctx->fallback, key, len);
> -
> -	tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
> -	tfm->crt_flags |= crypto_sync_skcipher_get_flags(xts_ctx->fallback) &
> -			  CRYPTO_TFM_RES_MASK;
> -
> -	return ret;
> -}
> -
> -static int xts_fallback_decrypt(struct blkcipher_desc *desc,
> -		struct scatterlist *dst, struct scatterlist *src,
> -		unsigned int nbytes)
> -{
> -	struct crypto_blkcipher *tfm = desc->tfm;
> -	struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(tfm);
> -	SYNC_SKCIPHER_REQUEST_ON_STACK(req, xts_ctx->fallback);
> -	unsigned int ret;
> -
> -	skcipher_request_set_sync_tfm(req, xts_ctx->fallback);
> -	skcipher_request_set_callback(req, desc->flags, NULL, NULL);
> -	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
> -
> -	ret = crypto_skcipher_decrypt(req);
> -
> -	skcipher_request_zero(req);
> -	return ret;
> -}
> -
> -static int xts_fallback_encrypt(struct blkcipher_desc *desc,
> -		struct scatterlist *dst, struct scatterlist *src,
> -		unsigned int nbytes)
> +static int xts_fallback_setkey(struct crypto_skcipher *tfm, const u8 *key,
> +			       unsigned int len)
>  {
> -	struct crypto_blkcipher *tfm = desc->tfm;
> -	struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(tfm);
> -	SYNC_SKCIPHER_REQUEST_ON_STACK(req, xts_ctx->fallback);
> -	unsigned int ret;
> -
> -	skcipher_request_set_sync_tfm(req, xts_ctx->fallback);
> -	skcipher_request_set_callback(req, desc->flags, NULL, NULL);
> -	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
> -
> -	ret = crypto_skcipher_encrypt(req);
> +	struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
> +	int ret;
>  
> -	skcipher_request_zero(req);
> +	crypto_skcipher_clear_flags(xts_ctx->fallback, CRYPTO_TFM_REQ_MASK);
> +	crypto_skcipher_set_flags(xts_ctx->fallback,
> +				  crypto_skcipher_get_flags(tfm) &
> +				  CRYPTO_TFM_REQ_MASK);
> +	ret = crypto_skcipher_setkey(xts_ctx->fallback, key, len);
> +	crypto_skcipher_set_flags(tfm,
> +				  crypto_skcipher_get_flags(xts_ctx->fallback) &
> +				  CRYPTO_TFM_RES_MASK);
>  	return ret;
>  }
>  
> -static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
> +static int xts_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
>  			   unsigned int key_len)
>  {
> -	struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
> +	struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
>  	unsigned long fc;
>  	int err;
>  
> @@ -518,7 +415,7 @@ static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
>  
>  	/* In fips mode only 128 bit or 256 bit keys are valid */
>  	if (fips_enabled && key_len != 32 && key_len != 64) {
> -		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
> +		crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
>  		return -EINVAL;
>  	}
>  
> @@ -539,10 +436,11 @@ static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
>  	return 0;
>  }
>  
> -static int xts_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
> -			 struct blkcipher_walk *walk)
> +static int xts_aes_crypt(struct skcipher_request *req, unsigned long modifier)
>  {
> -	struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm);
> +	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> +	struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
> +	struct skcipher_walk walk;
>  	unsigned int offset, nbytes, n;
>  	int ret;
>  	struct {
> @@ -557,113 +455,100 @@ static int xts_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
>  		u8 init[16];
>  	} xts_param;
>  
> -	ret = blkcipher_walk_virt(desc, walk);
> +	if (req->cryptlen < AES_BLOCK_SIZE)
> +		return -EINVAL;
> +
> +	if (unlikely(!xts_ctx->fc || (req->cryptlen % AES_BLOCK_SIZE) != 0)) {
> +		struct skcipher_request *subreq = skcipher_request_ctx(req);
> +
> +		*subreq = *req;
> +		skcipher_request_set_tfm(subreq, xts_ctx->fallback);
> +		return (modifier & CPACF_DECRYPT) ?
> +			crypto_skcipher_decrypt(subreq) :
> +			crypto_skcipher_encrypt(subreq);
> +	}
> +
> +	ret = skcipher_walk_virt(&walk, req, false);
> +	if (ret)
> +		return ret;
>  	offset = xts_ctx->key_len & 0x10;
>  	memset(pcc_param.block, 0, sizeof(pcc_param.block));
>  	memset(pcc_param.bit, 0, sizeof(pcc_param.bit));
>  	memset(pcc_param.xts, 0, sizeof(pcc_param.xts));
> -	memcpy(pcc_param.tweak, walk->iv, sizeof(pcc_param.tweak));
> +	memcpy(pcc_param.tweak, walk.iv, sizeof(pcc_param.tweak));
>  	memcpy(pcc_param.key + offset, xts_ctx->pcc_key, xts_ctx->key_len);
>  	cpacf_pcc(xts_ctx->fc, pcc_param.key + offset);
>  
>  	memcpy(xts_param.key + offset, xts_ctx->key, xts_ctx->key_len);
>  	memcpy(xts_param.init, pcc_param.xts, 16);
>  
> -	while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
> +	while ((nbytes = walk.nbytes) != 0) {
>  		/* only use complete blocks */
>  		n = nbytes & ~(AES_BLOCK_SIZE - 1);
>  		cpacf_km(xts_ctx->fc | modifier, xts_param.key + offset,
> -			 walk->dst.virt.addr, walk->src.virt.addr, n);
> -		ret = blkcipher_walk_done(desc, walk, nbytes - n);
> +			 walk.dst.virt.addr, walk.src.virt.addr, n);
> +		ret = skcipher_walk_done(&walk, nbytes - n);
>  	}
>  	return ret;
>  }
>  
> -static int xts_aes_encrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> +static int xts_aes_encrypt(struct skcipher_request *req)
>  {
> -	struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (!nbytes)
> -		return -EINVAL;
> -
> -	if (unlikely(!xts_ctx->fc || (nbytes % XTS_BLOCK_SIZE) != 0))
> -		return xts_fallback_encrypt(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return xts_aes_crypt(desc, 0, &walk);
> +	return xts_aes_crypt(req, 0);
>  }
>  
> -static int xts_aes_decrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> +static int xts_aes_decrypt(struct skcipher_request *req)
>  {
> -	struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (!nbytes)
> -		return -EINVAL;
> -
> -	if (unlikely(!xts_ctx->fc || (nbytes % XTS_BLOCK_SIZE) != 0))
> -		return xts_fallback_decrypt(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return xts_aes_crypt(desc, CPACF_DECRYPT, &walk);
> +	return xts_aes_crypt(req, CPACF_DECRYPT);
>  }
>  
> -static int xts_fallback_init(struct crypto_tfm *tfm)
> +static int xts_fallback_init(struct crypto_skcipher *tfm)
>  {
> -	const char *name = tfm->__crt_alg->cra_name;
> -	struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
> +	const char *name = crypto_tfm_alg_name(&tfm->base);
> +	struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
>  
> -	xts_ctx->fallback = crypto_alloc_sync_skcipher(name, 0,
> -						  CRYPTO_ALG_NEED_FALLBACK);
> +	xts_ctx->fallback = crypto_alloc_skcipher(name, 0,
> +				CRYPTO_ALG_NEED_FALLBACK | CRYPTO_ALG_ASYNC);
>  
>  	if (IS_ERR(xts_ctx->fallback)) {
>  		pr_err("Allocating XTS fallback algorithm %s failed\n",
>  		       name);
>  		return PTR_ERR(xts_ctx->fallback);
>  	}
> +	crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
> +				    crypto_skcipher_reqsize(xts_ctx->fallback));
>  	return 0;
>  }
>  
> -static void xts_fallback_exit(struct crypto_tfm *tfm)
> +static void xts_fallback_exit(struct crypto_skcipher *tfm)
>  {
> -	struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
> +	struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
>  
> -	crypto_free_sync_skcipher(xts_ctx->fallback);
> +	crypto_free_skcipher(xts_ctx->fallback);
>  }
>  
> -static struct crypto_alg xts_aes_alg = {
> -	.cra_name		=	"xts(aes)",
> -	.cra_driver_name	=	"xts-aes-s390",
> -	.cra_priority		=	402,	/* ecb-aes-s390 + 1 */
> -	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER |
> -					CRYPTO_ALG_NEED_FALLBACK,
> -	.cra_blocksize		=	AES_BLOCK_SIZE,
> -	.cra_ctxsize		=	sizeof(struct s390_xts_ctx),
> -	.cra_type		=	&crypto_blkcipher_type,
> -	.cra_module		=	THIS_MODULE,
> -	.cra_init		=	xts_fallback_init,
> -	.cra_exit		=	xts_fallback_exit,
> -	.cra_u			=	{
> -		.blkcipher = {
> -			.min_keysize		=	2 * AES_MIN_KEY_SIZE,
> -			.max_keysize		=	2 * AES_MAX_KEY_SIZE,
> -			.ivsize			=	AES_BLOCK_SIZE,
> -			.setkey			=	xts_aes_set_key,
> -			.encrypt		=	xts_aes_encrypt,
> -			.decrypt		=	xts_aes_decrypt,
> -		}
> -	}
> +static struct skcipher_alg xts_aes_alg = {
> +	.base.cra_name		=	"xts(aes)",
> +	.base.cra_driver_name	=	"xts-aes-s390",
> +	.base.cra_priority	=	402,	/* ecb-aes-s390 + 1 */
> +	.base.cra_flags		=	CRYPTO_ALG_NEED_FALLBACK,
> +	.base.cra_blocksize	=	AES_BLOCK_SIZE,
> +	.base.cra_ctxsize	=	sizeof(struct s390_xts_ctx),
> +	.base.cra_module	=	THIS_MODULE,
> +	.init			=	xts_fallback_init,
> +	.exit			=	xts_fallback_exit,
> +	.min_keysize		=	2 * AES_MIN_KEY_SIZE,
> +	.max_keysize		=	2 * AES_MAX_KEY_SIZE,
> +	.ivsize			=	AES_BLOCK_SIZE,
> +	.setkey			=	xts_aes_set_key,
> +	.encrypt		=	xts_aes_encrypt,
> +	.decrypt		=	xts_aes_decrypt,
>  };
>  
> -static int ctr_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
> +static int ctr_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
>  			   unsigned int key_len)
>  {
> -	struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
>  	unsigned long fc;
>  
>  	/* Pick the correct function code based on the key length */
> @@ -674,7 +559,7 @@ static int ctr_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
>  	/* Check if the function code is available */
>  	sctx->fc = (fc && cpacf_test_func(&kmctr_functions, fc)) ? fc : 0;
>  	if (!sctx->fc)
> -		return setkey_fallback_blk(tfm, in_key, key_len);
> +		return setkey_fallback_skcipher(tfm, in_key, key_len);
>  
>  	sctx->key_len = key_len;
>  	memcpy(sctx->key, in_key, key_len);
> @@ -696,30 +581,34 @@ static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes)
>  	return n;
>  }
>  
> -static int ctr_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
> -			 struct blkcipher_walk *walk)
> +static int ctr_aes_crypt(struct skcipher_request *req)
>  {
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> +	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> +	struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
>  	u8 buf[AES_BLOCK_SIZE], *ctrptr;
> +	struct skcipher_walk walk;
>  	unsigned int n, nbytes;
>  	int ret, locked;
>  
> +	if (unlikely(!sctx->fc))
> +		return fallback_skcipher_crypt(sctx, req, 0);
> +
>  	locked = mutex_trylock(&ctrblk_lock);
>  
> -	ret = blkcipher_walk_virt_block(desc, walk, AES_BLOCK_SIZE);
> -	while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
> +	ret = skcipher_walk_virt(&walk, req, false);
> +	while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
>  		n = AES_BLOCK_SIZE;
> +
>  		if (nbytes >= 2*AES_BLOCK_SIZE && locked)
> -			n = __ctrblk_init(ctrblk, walk->iv, nbytes);
> -		ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk->iv;
> -		cpacf_kmctr(sctx->fc | modifier, sctx->key,
> -			    walk->dst.virt.addr, walk->src.virt.addr,
> -			    n, ctrptr);
> +			n = __ctrblk_init(ctrblk, walk.iv, nbytes);
> +		ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk.iv;
> +		cpacf_kmctr(sctx->fc, sctx->key, walk.dst.virt.addr,
> +			    walk.src.virt.addr, n, ctrptr);
>  		if (ctrptr == ctrblk)
> -			memcpy(walk->iv, ctrptr + n - AES_BLOCK_SIZE,
> +			memcpy(walk.iv, ctrptr + n - AES_BLOCK_SIZE,
>  			       AES_BLOCK_SIZE);
> -		crypto_inc(walk->iv, AES_BLOCK_SIZE);
> -		ret = blkcipher_walk_done(desc, walk, nbytes - n);
> +		crypto_inc(walk.iv, AES_BLOCK_SIZE);
> +		ret = skcipher_walk_done(&walk, nbytes - n);
>  	}
>  	if (locked)
>  		mutex_unlock(&ctrblk_lock);
> @@ -727,67 +616,33 @@ static int ctr_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
>  	 * final block may be < AES_BLOCK_SIZE, copy only nbytes
>  	 */
>  	if (nbytes) {
> -		cpacf_kmctr(sctx->fc | modifier, sctx->key,
> -			    buf, walk->src.virt.addr,
> -			    AES_BLOCK_SIZE, walk->iv);
> -		memcpy(walk->dst.virt.addr, buf, nbytes);
> -		crypto_inc(walk->iv, AES_BLOCK_SIZE);
> -		ret = blkcipher_walk_done(desc, walk, 0);
> +		cpacf_kmctr(sctx->fc, sctx->key, buf, walk.src.virt.addr,
> +			    AES_BLOCK_SIZE, walk.iv);
> +		memcpy(walk.dst.virt.addr, buf, nbytes);
> +		crypto_inc(walk.iv, AES_BLOCK_SIZE);
> +		ret = skcipher_walk_done(&walk, 0);
>  	}
>  
>  	return ret;
>  }
>  
> -static int ctr_aes_encrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> -{
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (unlikely(!sctx->fc))
> -		return fallback_blk_enc(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return ctr_aes_crypt(desc, 0, &walk);
> -}
> -
> -static int ctr_aes_decrypt(struct blkcipher_desc *desc,
> -			   struct scatterlist *dst, struct scatterlist *src,
> -			   unsigned int nbytes)
> -{
> -	struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
> -	struct blkcipher_walk walk;
> -
> -	if (unlikely(!sctx->fc))
> -		return fallback_blk_dec(desc, dst, src, nbytes);
> -
> -	blkcipher_walk_init(&walk, dst, src, nbytes);
> -	return ctr_aes_crypt(desc, CPACF_DECRYPT, &walk);
> -}
> -
> -static struct crypto_alg ctr_aes_alg = {
> -	.cra_name		=	"ctr(aes)",
> -	.cra_driver_name	=	"ctr-aes-s390",
> -	.cra_priority		=	402,	/* ecb-aes-s390 + 1 */
> -	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER |
> -					CRYPTO_ALG_NEED_FALLBACK,
> -	.cra_blocksize		=	1,
> -	.cra_ctxsize		=	sizeof(struct s390_aes_ctx),
> -	.cra_type		=	&crypto_blkcipher_type,
> -	.cra_module		=	THIS_MODULE,
> -	.cra_init		=	fallback_init_blk,
> -	.cra_exit		=	fallback_exit_blk,
> -	.cra_u			=	{
> -		.blkcipher = {
> -			.min_keysize		=	AES_MIN_KEY_SIZE,
> -			.max_keysize		=	AES_MAX_KEY_SIZE,
> -			.ivsize			=	AES_BLOCK_SIZE,
> -			.setkey			=	ctr_aes_set_key,
> -			.encrypt		=	ctr_aes_encrypt,
> -			.decrypt		=	ctr_aes_decrypt,
> -		}
> -	}
> +static struct skcipher_alg ctr_aes_alg = {
> +	.base.cra_name		=	"ctr(aes)",
> +	.base.cra_driver_name	=	"ctr-aes-s390",
> +	.base.cra_priority	=	402,	/* ecb-aes-s390 + 1 */
> +	.base.cra_flags		=	CRYPTO_ALG_NEED_FALLBACK,
> +	.base.cra_blocksize	=	1,
> +	.base.cra_ctxsize	=	sizeof(struct s390_aes_ctx),
> +	.base.cra_module	=	THIS_MODULE,
> +	.init			=	fallback_init_skcipher,
> +	.exit			=	fallback_exit_skcipher,
> +	.min_keysize		=	AES_MIN_KEY_SIZE,
> +	.max_keysize		=	AES_MAX_KEY_SIZE,
> +	.ivsize			=	AES_BLOCK_SIZE,
> +	.setkey			=	ctr_aes_set_key,
> +	.encrypt		=	ctr_aes_crypt,
> +	.decrypt		=	ctr_aes_crypt,
> +	.chunksize		=	AES_BLOCK_SIZE,
>  };
>  
>  static int gcm_aes_setkey(struct crypto_aead *tfm, const u8 *key,
> @@ -1116,24 +971,27 @@ static struct aead_alg gcm_aes_aead = {
>  	},
>  };
>  
> -static struct crypto_alg *aes_s390_algs_ptr[5];
> -static int aes_s390_algs_num;
> +static struct crypto_alg *aes_s390_alg;
> +static struct skcipher_alg *aes_s390_skcipher_algs[4];
> +static int aes_s390_skciphers_num;
>  static struct aead_alg *aes_s390_aead_alg;
>  
> -static int aes_s390_register_alg(struct crypto_alg *alg)
> +static int aes_s390_register_skcipher(struct skcipher_alg *alg)
>  {
>  	int ret;
>  
> -	ret = crypto_register_alg(alg);
> +	ret = crypto_register_skcipher(alg);
>  	if (!ret)
> -		aes_s390_algs_ptr[aes_s390_algs_num++] = alg;
> +		aes_s390_skcipher_algs[aes_s390_skciphers_num++] = alg;
>  	return ret;
>  }
>  
>  static void aes_s390_fini(void)
>  {
> -	while (aes_s390_algs_num--)
> -		crypto_unregister_alg(aes_s390_algs_ptr[aes_s390_algs_num]);
> +	if (aes_s390_alg)
> +		crypto_unregister_alg(aes_s390_alg);
> +	while (aes_s390_skciphers_num--)
> +		crypto_unregister_skcipher(aes_s390_skcipher_algs[aes_s390_skciphers_num]);
>  	if (ctrblk)
>  		free_page((unsigned long) ctrblk);
>  
> @@ -1154,10 +1012,11 @@ static int __init aes_s390_init(void)
>  	if (cpacf_test_func(&km_functions, CPACF_KM_AES_128) ||
>  	    cpacf_test_func(&km_functions, CPACF_KM_AES_192) ||
>  	    cpacf_test_func(&km_functions, CPACF_KM_AES_256)) {
> -		ret = aes_s390_register_alg(&aes_alg);
> +		ret = crypto_register_alg(&aes_alg);
>  		if (ret)
>  			goto out_err;
> -		ret = aes_s390_register_alg(&ecb_aes_alg);
> +		aes_s390_alg = &aes_alg;
> +		ret = aes_s390_register_skcipher(&ecb_aes_alg);
>  		if (ret)
>  			goto out_err;
>  	}
> @@ -1165,14 +1024,14 @@ static int __init aes_s390_init(void)
>  	if (cpacf_test_func(&kmc_functions, CPACF_KMC_AES_128) ||
>  	    cpacf_test_func(&kmc_functions, CPACF_KMC_AES_192) ||
>  	    cpacf_test_func(&kmc_functions, CPACF_KMC_AES_256)) {
> -		ret = aes_s390_register_alg(&cbc_aes_alg);
> +		ret = aes_s390_register_skcipher(&cbc_aes_alg);
>  		if (ret)
>  			goto out_err;
>  	}
>  
>  	if (cpacf_test_func(&km_functions, CPACF_KM_XTS_128) ||
>  	    cpacf_test_func(&km_functions, CPACF_KM_XTS_256)) {
> -		ret = aes_s390_register_alg(&xts_aes_alg);
> +		ret = aes_s390_register_skcipher(&xts_aes_alg);
>  		if (ret)
>  			goto out_err;
>  	}
> @@ -1185,7 +1044,7 @@ static int __init aes_s390_init(void)
>  			ret = -ENOMEM;
>  			goto out_err;
>  		}
> -		ret = aes_s390_register_alg(&ctr_aes_alg);
> +		ret = aes_s390_register_skcipher(&ctr_aes_alg);
>  		if (ret)
>  			goto out_err;
>  	}

Tested with extended selftests and own tests via AF_ALG interface, works.
Thanks for this great work.
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>