crypto: omap-sham - Verify page zone of scatterlists before starting DMA

In certain platforms like DRA7xx having memory > 2GB with LPAE enabled
has a constraint that DMA can be done with the initial 2GB and marks it
as ZONE_DMA. But openssl when used with cryptodev does not make sure that
input buffer is DMA capable. So, adding a check to verify if the input
buffer is capable of DMA.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Reported-by: Aparna Balasubramanian <aparnab@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/omap-sham.c

@@ -759,6 +759,13 @@ static int omap_sham_align_sgs(struct scatterlist *sg,
 	while (nbytes > 0 && sg_tmp) {
 		n++;
 
+#ifdef CONFIG_ZONE_DMA
+		if (page_zonenum(sg_page(sg_tmp)) != ZONE_DMA) {
+			aligned = false;
+			break;
+		}
+#endif
+
 		if (offset < sg_tmp->length) {
 			if (!IS_ALIGNED(offset + sg_tmp->offset, 4)) {
 				aligned = false;