[PATCH 4/8] crypto: sun8i-ss: do not allocate memory when handling hash requests

[Corentin Labbe]

Instead of allocate memory on each requests, it is easier to
pre-allocate buffers.
This made error path easier.

Signed-off-by: Corentin Labbe <clabbe@xxxxxxxxxxxx>
---
 drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c | 10 ++++++++++
 drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c | 15 +++------------
 drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h      |  4 ++++
 3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c
index 319fe3279a71..084261d7899c 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c
@@ -474,6 +474,16 @@ static int allocate_flows(struct sun8i_ss_dev *ss)
 	for (i = 0; i < MAXFLOW; i++) {
 		init_completion(&ss->flows[i].complete);
 
+		/* the padding could be up to two block. */
+		ss->flows[i].pad = devm_kmalloc(ss->dev, SHA256_BLOCK_SIZE * 2,
+						GFP_KERNEL | GFP_DMA);
+		if (!ss->flows[i].pad)
+			goto error_engine;
+		ss->flows[i].result = devm_kmalloc(ss->dev, SHA256_DIGEST_SIZE,
+						   GFP_KERNEL | GFP_DMA);
+		if (!ss->flows[i].result)
+			goto error_engine;
+
 		ss->flows[i].engine = crypto_engine_alloc_init(ss->dev, true);
 		if (!ss->flows[i].engine) {
 			dev_err(ss->dev, "Cannot allocate engine\n");
diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
index 2557bb3fe7aa..f7a9578e87f7 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
@@ -341,18 +341,11 @@ int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
 	if (digestsize == SHA224_DIGEST_SIZE)
 		digestsize = SHA256_DIGEST_SIZE;
 
-	/* the padding could be up to two block. */
-	pad = kzalloc(algt->alg.hash.halg.base.cra_blocksize * 2, GFP_KERNEL | GFP_DMA);
-	if (!pad)
-		return -ENOMEM;
+	result = ss->flows[rctx->flow].result;
+	pad = ss->flows[rctx->flow].pad;
+	memset(pad, 0, algt->alg.hash.halg.base.cra_blocksize * 2);
 	bf = (__le32 *)pad;
 
-	result = kzalloc(digestsize, GFP_KERNEL | GFP_DMA);
-	if (!result) {
-		kfree(pad);
-		return -ENOMEM;
-	}
-
 	for (i = 0; i < MAX_SG; i++) {
 		rctx->t_dst[i].addr = 0;
 		rctx->t_dst[i].len = 0;
@@ -448,8 +441,6 @@ int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
 
 	memcpy(areq->result, result, algt->alg.hash.halg.digestsize);
 theend:
-	kfree(pad);
-	kfree(result);
 	crypto_finalize_hash_request(engine, breq, err);
 	return 0;
 }
diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h
index 28188685b910..f9f089ede934 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h
@@ -121,11 +121,15 @@ struct sginfo {
  * @complete:	completion for the current task on this flow
  * @status:	set to 1 by interrupt if task is done
  * @stat_req:	number of request done by this flow
+ * @pad:	padding buffer for hash operations
+ * @result:	buffer for storing the result of hash operations
  */
 struct sun8i_ss_flow {
 	struct crypto_engine *engine;
 	struct completion complete;
 	int status;
+	void *pad;
+	void *result;
 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
 	unsigned long stat_req;
 #endif
-- 
2.34.1