Revert "crypto: allwinner - Fix dma_map_sg error check"

This reverts commit 2b02187b.

The original code was correct and arguably more robust than the
patched version.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

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

@@ -208,7 +208,7 @@ static int sun8i_ce_cipher_prepare(struct crypto_engine *engine, void *async_req
 
 	if (areq->src == areq->dst) {
 		nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_BIDIRECTIONAL);
-		if (!nr_sgs || nr_sgs > MAX_SG) {
+		if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
 			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
 			err = -EINVAL;
 			goto theend_iv;
@@ -216,13 +216,13 @@ static int sun8i_ce_cipher_prepare(struct crypto_engine *engine, void *async_req
 		nr_sgd = nr_sgs;
 	} else {
 		nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
-		if (!nr_sgs || nr_sgs > MAX_SG) {
+		if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
 			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
 			err = -EINVAL;
 			goto theend_iv;
 		}
 		nr_sgd = dma_map_sg(ce->dev, areq->dst, nd, DMA_FROM_DEVICE);
-		if (!nr_sgd || nr_sgd > MAX_SG) {
+		if (nr_sgd <= 0 || nr_sgd > MAX_SG) {
 			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgd);
 			err = -EINVAL;
 			goto theend_sgs;

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

@@ -389,7 +389,7 @@ int sun8i_ce_hash_run(struct crypto_engine *engine, void *breq)
 	cet->t_asym_ctl = 0;
 
 	nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
-	if (!nr_sgs || nr_sgs > MAX_SG) {
+	if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
 		dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
 		err = -EINVAL;
 		goto theend;

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

@@ -232,13 +232,13 @@ static int sun8i_ss_cipher(struct skcipher_request *areq)
 		nr_sgd = nr_sgs;
 	} else {
 		nr_sgs = dma_map_sg(ss->dev, areq->src, nsgs, DMA_TO_DEVICE);
-		if (!nr_sgs || nr_sgs > 8) {
+		if (nr_sgs <= 0 || nr_sgs > 8) {
 			dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
 			err = -EINVAL;
 			goto theend_iv;
 		}
 		nr_sgd = dma_map_sg(ss->dev, areq->dst, nsgd, DMA_FROM_DEVICE);
-		if (!nr_sgd || nr_sgd > 8) {
+		if (nr_sgd <= 0 || nr_sgd > 8) {
 			dev_err(ss->dev, "Invalid sg number %d\n", nr_sgd);
 			err = -EINVAL;
 			goto theend_sgs;

drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c

@@ -527,7 +527,7 @@ int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
 	rctx->method = ss->variant->alg_hash[algt->ss_algo_id];
 
 	nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
-	if (!nr_sgs || nr_sgs > MAX_SG) {
+	if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
 		dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
 		err = -EINVAL;
 		goto theend;