2017-06-23 14:15:39

by Harsh Jain

Subject: [PATCH] crypto: chcr: Avoid algo allocation in softirq.

Thsi patch fixes calling "crypto_alloc_cipher" call in bottom halves.
Pre allocate aes cipher required to update Tweak value for XTS.

Signed-off-by: Harsh Jain <[email protected]>
---
drivers/crypto/chelsio/chcr_algo.c | 23 +++++++++++++++--------
drivers/crypto/chelsio/chcr_crypto.h | 1 +
2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/crypto/chelsio/chcr_algo.c b/drivers/crypto/chelsio/chcr_algo.c
index aa4e5b8..508cbc7 100644
--- a/drivers/crypto/chelsio/chcr_algo.c
+++ b/drivers/crypto/chelsio/chcr_algo.c
@@ -899,26 +899,20 @@ static int chcr_update_tweak(struct ablkcipher_request *req, u8 *iv)
u8 *key;
unsigned int keylen;

- cipher = crypto_alloc_cipher("aes-generic", 0, 0);
+ cipher = ablkctx->aes_generic;
memcpy(iv, req->info, AES_BLOCK_SIZE);

- if (IS_ERR(cipher)) {
- ret = -ENOMEM;
- goto out;
- }
keylen = ablkctx->enckey_len / 2;
key = ablkctx->key + keylen;
ret = crypto_cipher_setkey(cipher, key, keylen);
if (ret)
- goto out1;
+ goto out;

crypto_cipher_encrypt_one(cipher, iv, iv);
for (i = 0; i < (reqctx->processed / AES_BLOCK_SIZE); i++)
gf128mul_x_ble((le128 *)iv, (le128 *)iv);

crypto_cipher_decrypt_one(cipher, iv, iv);
-out1:
- crypto_free_cipher(cipher);
out:
return ret;
}
@@ -1262,6 +1256,17 @@ static int chcr_cra_init(struct crypto_tfm *tfm)
pr_err("failed to allocate fallback for %s\n", alg->cra_name);
return PTR_ERR(ablkctx->sw_cipher);
}
+
+ if (get_cryptoalg_subtype(tfm) == CRYPTO_ALG_SUB_TYPE_XTS) {
+ /* To update tweak*/
+ ablkctx->aes_generic = crypto_alloc_cipher("aes-generic", 0, 0);
+ if (IS_ERR(ablkctx->aes_generic)) {
+ pr_err("failed to allocate aes cipher for tweak\n");
+ return PTR_ERR(ablkctx->aes_generic);
+ }
+ } else
+ ablkctx->aes_generic = NULL;
+
tfm->crt_ablkcipher.reqsize = sizeof(struct chcr_blkcipher_req_ctx);
return chcr_device_init(crypto_tfm_ctx(tfm));
}
@@ -1292,6 +1297,8 @@ static void chcr_cra_exit(struct crypto_tfm *tfm)
struct ablk_ctx *ablkctx = ABLK_CTX(ctx);

crypto_free_skcipher(ablkctx->sw_cipher);
+ if (ablkctx->aes_generic)
+ crypto_free_cipher(ablkctx->aes_generic);
}

static int get_alg_config(struct algo_param *params,
diff --git a/drivers/crypto/chelsio/chcr_crypto.h b/drivers/crypto/chelsio/chcr_crypto.h
index a4f95b0..30af1ee 100644
--- a/drivers/crypto/chelsio/chcr_crypto.h
+++ b/drivers/crypto/chelsio/chcr_crypto.h
@@ -155,6 +155,7 @@

struct ablk_ctx {
struct crypto_skcipher *sw_cipher;
+ struct crypto_cipher *aes_generic;
__be32 key_ctx_hdr;
unsigned int enckey_len;
unsigned char ciph_mode;
--
2.1.4

2017-07-12 10:52:36

by Herbert Xu

Subject: Re: [PATCH] crypto: chcr: Avoid algo allocation in softirq.

On Fri, Jun 23, 2017 at 07:45:11PM +0530, Harsh Jain wrote:
> Thsi patch fixes calling "crypto_alloc_cipher" call in bottom halves.
> Pre allocate aes cipher required to update Tweak value for XTS.
>
> Signed-off-by: Harsh Jain <[email protected]>

Patch applied. Thanks.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt