crypto: omap-crypto - Verify page zone 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>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/omap-crypto.c b/drivers/crypto/omap-crypto.c
index 23e3777..2c42e4b 100644
--- a/drivers/crypto/omap-crypto.c
+++ b/drivers/crypto/omap-crypto.c
@@ -104,6 +104,10 @@
 			return OMAP_CRYPTO_NOT_ALIGNED;
 		if (!IS_ALIGNED(sg->length, bs))
 			return OMAP_CRYPTO_NOT_ALIGNED;
+#ifdef CONFIG_ZONE_DMA
+		if (page_zonenum(sg_page(sg)) != ZONE_DMA)
+			return OMAP_CRYPTO_NOT_ALIGNED;
+#endif
 
 		len += sg->length;
 		sg = sg_next(sg);