struct mv_cesa_tdma_chain chain;
        struct mv_cesa_ahash_dma_iter iter;
        struct mv_cesa_op_ctx *op = NULL;
+       unsigned int frag_len;
        int ret;
 
        dreq->chain.first = NULL;
                /*
                 * Add all the new data, inserting an operation block and
                 * launch command between each full SRAM block-worth of
-                * data.
+                * data. We intentionally do not add the final op block.
                 */
-               do {
+               while (true) {
                        ret = mv_cesa_dma_add_op_transfers(&chain, &iter.base,
                                                           &iter.src, flags);
                        if (ret)
                                goto err_free_tdma;
 
+                       frag_len = iter.base.op_len;
+
+                       if (!mv_cesa_ahash_req_iter_next_op(&iter))
+                               break;
+
                        op = mv_cesa_dma_add_frag(&chain, &creq->op_tmpl,
-                                                 iter.base.op_len, flags);
+                                                 frag_len, flags);
                        if (IS_ERR(op)) {
                                ret = PTR_ERR(op);
                                goto err_free_tdma;
                        }
-               } while (mv_cesa_ahash_req_iter_next_op(&iter));
-       } else if (iter.base.op_len) {
+               }
+       } else {
                /* Account for the data that was in the cache. */
-               op = mv_cesa_dma_add_frag(&chain, &creq->op_tmpl,
-                                         iter.base.op_len, flags);
+               frag_len = iter.base.op_len;
+       }
+
+       if (frag_len) {
+               op = mv_cesa_dma_add_frag(&chain, &creq->op_tmpl, frag_len,
+                                         flags);
                if (IS_ERR(op)) {
                        ret = PTR_ERR(op);
                        goto err_free_tdma;