crypto: sun8i-ce - split into prepare/run/unprepare

This patch split the do_one_request into three.
Prepare will handle all DMA mapping and initialisation of the task
structure.
Unprepare will clean all DMA mapping.
And the do_one_request will be limited to just executing the task.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c

@@ -75,8 +75,9 @@ static int sun8i_ce_cipher_fallback(struct skcipher_request *areq)
 	return err;
 }
 
-static int sun8i_ce_cipher(struct skcipher_request *areq)
+static int sun8i_ce_cipher_prepare(struct crypto_engine *engine, void *async_req)
 {
+	struct skcipher_request *areq = container_of(async_req, struct skcipher_request, base);
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
 	struct sun8i_ce_dev *ce = op->ce;
@@ -87,7 +88,6 @@ static int sun8i_ce_cipher(struct skcipher_request *areq)
 	struct ce_task *cet;
 	struct scatterlist *sg;
 	unsigned int todo, len, offset, ivsize;
-	dma_addr_t addr_iv = 0, addr_key = 0;
 	u32 common, sym;
 	int flow, i;
 	int nr_sgs = 0;
@@ -140,13 +140,13 @@ static int sun8i_ce_cipher(struct skcipher_request *areq)
 	cet->t_sym_ctl = cpu_to_le32(sym);
 	cet->t_asym_ctl = 0;
 
-	addr_key = dma_map_single(ce->dev, op->key, op->keylen, DMA_TO_DEVICE);
-	cet->t_key = cpu_to_le32(addr_key);
-	if (dma_mapping_error(ce->dev, addr_key)) {
+	rctx->addr_key = dma_map_single(ce->dev, op->key, op->keylen, DMA_TO_DEVICE);
+	if (dma_mapping_error(ce->dev, rctx->addr_key)) {
 		dev_err(ce->dev, "Cannot DMA MAP KEY\n");
 		err = -EFAULT;
 		goto theend;
 	}
+	cet->t_key = cpu_to_le32(rctx->addr_key);
 
 	ivsize = crypto_skcipher_ivsize(tfm);
 	if (areq->iv && crypto_skcipher_ivsize(tfm) > 0) {
@@ -167,14 +167,14 @@ static int sun8i_ce_cipher(struct skcipher_request *areq)
 						 offset, ivsize, 0);
 		}
 		memcpy(rctx->bounce_iv, areq->iv, ivsize);
-		addr_iv = dma_map_single(ce->dev, rctx->bounce_iv, rctx->ivlen,
-					 DMA_TO_DEVICE);
-		cet->t_iv = cpu_to_le32(addr_iv);
-		if (dma_mapping_error(ce->dev, addr_iv)) {
+		rctx->addr_iv = dma_map_single(ce->dev, rctx->bounce_iv, rctx->ivlen,
+					       DMA_TO_DEVICE);
+		if (dma_mapping_error(ce->dev, rctx->addr_iv)) {
 			dev_err(ce->dev, "Cannot DMA MAP IV\n");
 			err = -ENOMEM;
 			goto theend_iv;
 		}
+		cet->t_iv = cpu_to_le32(rctx->addr_iv);
 	}
 
 	if (areq->src == areq->dst) {
@@ -234,7 +234,9 @@ static int sun8i_ce_cipher(struct skcipher_request *areq)
 	}
 
 	chan->timeout = areq->cryptlen;
-	err = sun8i_ce_run_task(ce, flow, crypto_tfm_alg_name(areq->base.tfm));
+	rctx->nr_sgs = nr_sgs;
+	rctx->nr_sgd = nr_sgd;
+	return 0;
 
 theend_sgs:
 	if (areq->src == areq->dst) {
@@ -247,9 +249,8 @@ static int sun8i_ce_cipher(struct skcipher_request *areq)
 
 theend_iv:
 	if (areq->iv && ivsize > 0) {
-		if (addr_iv)
-			dma_unmap_single(ce->dev, addr_iv, rctx->ivlen,
-					 DMA_TO_DEVICE);
+		if (rctx->addr_iv)
+			dma_unmap_single(ce->dev, rctx->addr_iv, rctx->ivlen, DMA_TO_DEVICE);
 		offset = areq->cryptlen - ivsize;
 		if (rctx->op_dir & CE_DECRYPTION) {
 			memcpy(areq->iv, rctx->backup_iv, ivsize);
@@ -262,19 +263,69 @@ static int sun8i_ce_cipher(struct skcipher_request *areq)
 	}
 
 theend_key:
-	dma_unmap_single(ce->dev, addr_key, op->keylen, DMA_TO_DEVICE);
+	dma_unmap_single(ce->dev, rctx->addr_key, op->keylen, DMA_TO_DEVICE);
 
 theend:
 	return err;
 }
 
-static int sun8i_ce_handle_cipher_request(struct crypto_engine *engine, void *areq)
+static int sun8i_ce_cipher_run(struct crypto_engine *engine, void *areq)
 {
-	int err;
 	struct skcipher_request *breq = container_of(areq, struct skcipher_request, base);
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(breq);
+	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct sun8i_ce_dev *ce = op->ce;
+	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(breq);
+	int flow, err;
 
-	err = sun8i_ce_cipher(breq);
+	flow = rctx->flow;
+	err = sun8i_ce_run_task(ce, flow, crypto_tfm_alg_name(breq->base.tfm));
 	crypto_finalize_skcipher_request(engine, breq, err);
+	return 0;
+}
+
+static int sun8i_ce_cipher_unprepare(struct crypto_engine *engine, void *async_req)
+{
+	struct skcipher_request *areq = container_of(async_req, struct skcipher_request, base);
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
+	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
+	struct sun8i_ce_dev *ce = op->ce;
+	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
+	struct sun8i_ce_flow *chan;
+	struct ce_task *cet;
+	unsigned int ivsize, offset;
+	int nr_sgs = rctx->nr_sgs;
+	int nr_sgd = rctx->nr_sgd;
+	int flow;
+
+	flow = rctx->flow;
+	chan = &ce->chanlist[flow];
+	cet = chan->tl;
+	ivsize = crypto_skcipher_ivsize(tfm);
+
+	if (areq->src == areq->dst) {
+		dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
+	} else {
+		if (nr_sgs > 0)
+			dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
+		dma_unmap_sg(ce->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
+	}
+
+	if (areq->iv && ivsize > 0) {
+		if (cet->t_iv)
+			dma_unmap_single(ce->dev, rctx->addr_iv, rctx->ivlen, DMA_TO_DEVICE);
+		offset = areq->cryptlen - ivsize;
+		if (rctx->op_dir & CE_DECRYPTION) {
+			memcpy(areq->iv, rctx->backup_iv, ivsize);
+			kfree_sensitive(rctx->backup_iv);
+		} else {
+			scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
+						 ivsize, 0);
+		}
+		kfree(rctx->bounce_iv);
+	}
+
+	dma_unmap_single(ce->dev, rctx->addr_key, op->keylen, DMA_TO_DEVICE);
 
 	return 0;
 }
@@ -346,9 +397,9 @@ int sun8i_ce_cipher_init(struct crypto_tfm *tfm)
 		 crypto_tfm_alg_driver_name(&sktfm->base),
 		 crypto_tfm_alg_driver_name(crypto_skcipher_tfm(op->fallback_tfm)));
 
-	op->enginectx.op.do_one_request = sun8i_ce_handle_cipher_request;
-	op->enginectx.op.prepare_request = NULL;
-	op->enginectx.op.unprepare_request = NULL;
+	op->enginectx.op.do_one_request = sun8i_ce_cipher_run;
+	op->enginectx.op.prepare_request = sun8i_ce_cipher_prepare;
+	op->enginectx.op.unprepare_request = sun8i_ce_cipher_unprepare;
 
 	err = pm_runtime_get_sync(op->ce->dev);
 	if (err < 0)

drivers/crypto/allwinner/sun8i-ce/sun8i-ce.h

@@ -182,6 +182,10 @@ struct sun8i_ce_dev {
  * @backup_iv:		buffer which contain the next IV to store
  * @bounce_iv:		buffer which contain the IV
  * @ivlen:		size of bounce_iv
+ * @nr_sgs:		The number of source SG (as given by dma_map_sg())
+ * @nr_sgd:		The number of destination SG (as given by dma_map_sg())
+ * @addr_iv:		The IV addr returned by dma_map_single, need to unmap later
+ * @addr_key:		The key addr returned by dma_map_single, need to unmap later
  * @fallback_req:	request struct for invoking the fallback skcipher TFM
  */
 struct sun8i_cipher_req_ctx {
@@ -190,6 +194,10 @@ struct sun8i_cipher_req_ctx {
 	void *backup_iv;
 	void *bounce_iv;
 	unsigned int ivlen;
+	int nr_sgs;
+	int nr_sgd;
+	dma_addr_t addr_iv;
+	dma_addr_t addr_key;
 	struct skcipher_request fallback_req;   // keep at the end
 };