crypto: caam - Correct the dma mapping for sg table

At few places in caamhash and caamalg, after allocating a dmable
buffer for sg table , the buffer was being modified.  As per
definition of DMA_FROM_DEVICE ,afer allocation the memory should
be treated as read-only by the driver. This patch shifts the
allocation of dmable buffer for sg table after it is populated
by the  driver, making it read-only as per the DMA API's requirement.

Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c
index c09ce1f..87d9de4 100644
--- a/drivers/crypto/caam/caamalg.c
+++ b/drivers/crypto/caam/caamalg.c
@@ -1345,8 +1345,6 @@
 	edesc->sec4_sg_bytes = sec4_sg_bytes;
 	edesc->sec4_sg = (void *)edesc + sizeof(struct aead_edesc) +
 			 desc_bytes;
-	edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,
-					    sec4_sg_bytes, DMA_TO_DEVICE);
 	*all_contig_ptr = all_contig;
 
 	sec4_sg_index = 0;
@@ -1369,6 +1367,8 @@
 		sg_to_sec4_sg_last(req->dst, dst_nents,
 				   edesc->sec4_sg + sec4_sg_index, 0);
 	}
+	edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,
+					    sec4_sg_bytes, DMA_TO_DEVICE);
 
 	return edesc;
 }
@@ -1534,8 +1534,6 @@
 	edesc->sec4_sg_bytes = sec4_sg_bytes;
 	edesc->sec4_sg = (void *)edesc + sizeof(struct aead_edesc) +
 			 desc_bytes;
-	edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,
-					    sec4_sg_bytes, DMA_TO_DEVICE);
 	*contig_ptr = contig;
 
 	sec4_sg_index = 0;
@@ -1559,6 +1557,8 @@
 		sg_to_sec4_sg_last(req->dst, dst_nents,
 				   edesc->sec4_sg + sec4_sg_index, 0);
 	}
+	edesc->sec4_sg_dma = dma_map_single(jrdev, edesc->sec4_sg,
+					    sec4_sg_bytes, DMA_TO_DEVICE);
 
 	return edesc;
 }