crypto: nx - add offset to nx_build_sg_lists()

This patch includes one more parameter to nx_build_sg_lists() to skip
the given number of bytes from beginning of each sg list.

This is needed in order to implement the fixes for the AES modes to make
them able to process larger chunks of data.

Reviewed-by: Joy Latten <jmlatten@linux.vnet.ibm.com>
Signed-off-by: Marcelo Cerri <mhcerri@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/nx/nx.c b/drivers/crypto/nx/nx.c
index bdf4990..5533fe3 100644
--- a/drivers/crypto/nx/nx.c
+++ b/drivers/crypto/nx/nx.c
@@ -211,6 +211,8 @@
  * @dst: destination scatterlist
  * @src: source scatterlist
  * @nbytes: length of data described in the scatterlists
+ * @offset: number of bytes to fast-forward past at the beginning of
+ *          scatterlists.
  * @iv: destination for the iv data, if the algorithm requires it
  *
  * This is common code shared by all the AES algorithms. It uses the block
@@ -222,6 +224,7 @@
 		      struct scatterlist    *dst,
 		      struct scatterlist    *src,
 		      unsigned int           nbytes,
+		      unsigned int           offset,
 		      u8                    *iv)
 {
 	struct nx_sg *nx_insg = nx_ctx->in_sg;
@@ -230,8 +233,10 @@
 	if (iv)
 		memcpy(iv, desc->info, AES_BLOCK_SIZE);
 
-	nx_insg = nx_walk_and_build(nx_insg, nx_ctx->ap->sglen, src, 0, nbytes);
-	nx_outsg = nx_walk_and_build(nx_outsg, nx_ctx->ap->sglen, dst, 0, nbytes);
+	nx_insg = nx_walk_and_build(nx_insg, nx_ctx->ap->sglen, src,
+				    offset, nbytes);
+	nx_outsg = nx_walk_and_build(nx_outsg, nx_ctx->ap->sglen, dst,
+				    offset, nbytes);
 
 	/* these lengths should be negative, which will indicate to phyp that
 	 * the input and output parameters are scatterlists, not linear