crypto: marvell/cesa - use presence of scatterlist to determine data load
authorRussell King <rmk+kernel@arm.linux.org.uk>
Sun, 18 Oct 2015 16:24:21 +0000 (17:24 +0100)
committerHerbert Xu <herbert@gondor.apana.org.au>
Tue, 20 Oct 2015 14:11:06 +0000 (22:11 +0800)
Use the presence of the scatterlist to determine whether we should load
any new user data to the engine.  The following shall always be true at
this point:

iter.base.op_len == 0 === iter.src.sg

In doing so, we can:

1. eliminate the test for iter.base.op_len inside the loop, which
   makes the loop operation more obvious and understandable.

2. move the operation generation for the cache-only case.

This prepares the code for the next step in its transformation, and also
uncovers a bug that will be fixed in the next patch.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
drivers/crypto/marvell/hash.c

index d2a947ec1aebff51c8203e20b68a178c74238bdf..3497d7015ca7f0c2cabc1be1cf55ecd70ccfbd33 100644 (file)
@@ -627,7 +627,27 @@ static int mv_cesa_ahash_dma_req_init(struct ahash_request *req)
        if (ret)
                goto err_free_tdma;
 
-       if (creq->cache_ptr && !iter.base.op_len) {
+       if (iter.src.sg) {
+               /*
+                * Add all the new data, inserting an operation block and
+                * launch command between each full SRAM block-worth of
+                * data.
+                */
+               do {
+                       ret = mv_cesa_dma_add_op_transfers(&chain, &iter.base,
+                                                          &iter.src, flags);
+                       if (ret)
+                               goto err_free_tdma;
+
+                       op = mv_cesa_dma_add_frag(&chain, &creq->op_tmpl,
+                                                 iter.base.op_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 (creq->cache_ptr) {
+               /* Account for the data that was in the cache. */
                op = mv_cesa_dma_add_frag(&chain, &creq->op_tmpl,
                                          creq->cache_ptr, flags);
                if (IS_ERR(op)) {
@@ -636,23 +656,6 @@ static int mv_cesa_ahash_dma_req_init(struct ahash_request *req)
                }
        }
 
-       do {
-               if (!iter.base.op_len)
-                       break;
-
-               ret = mv_cesa_dma_add_op_transfers(&chain, &iter.base,
-                                                  &iter.src, flags);
-               if (ret)
-                       goto err_free_tdma;
-
-               op = mv_cesa_dma_add_frag(&chain, &creq->op_tmpl,
-                                         iter.base.op_len, flags);
-               if (IS_ERR(op)) {
-                       ret = PTR_ERR(op);
-                       goto err_free_tdma;
-               }
-       } while (mv_cesa_ahash_req_iter_next_op(&iter));
-
        op = mv_cesa_ahash_dma_last_req(&chain, &iter, creq, op, flags);
        if (IS_ERR(op)) {
                ret = PTR_ERR(op);