crypto: aspeed/hash - Iterate on large hashes in dma_prepare

Rather than failing a hash larger than ASPEED_CRYPTO_SRC_DMA_BUF_LEN,
just hash them over and over again until it's done.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/aspeed/aspeed-hace-hash.c b/drivers/crypto/aspeed/aspeed-hace-hash.c
index 3bfb7db96c40edd8935967b5bcca18de83cea797..fc2154947ec838dfda9f8e18f28e01b2f5e85104 100644 (file)
--- a/drivers/crypto/aspeed/aspeed-hace-hash.c
+++ b/drivers/crypto/aspeed/aspeed-hace-hash.c
@@ -155,26 +155,30 @@ static int aspeed_ahash_dma_prepare(struct aspeed_hace_dev *hace_dev)
        struct aspeed_engine_hash *hash_engine = &hace_dev->hash_engine;
        struct ahash_request *req = hash_engine->req;
        struct aspeed_sham_reqctx *rctx = ahash_request_ctx(req);
-       bool final = rctx->flags & SHA_FLAGS_FINUP;
        unsigned int length, remain;
+       bool final = false;
 
-       length = rctx->total;
-       remain = final ? 0 : length % rctx->block_size;
+       length = rctx->total - rctx->offset;
+       remain = length - round_down(length, rctx->block_size);
 
        AHASH_DBG(hace_dev, "length:0x%x, remain:0x%x\n", length, remain);
 
-       if ((final ? round_up(length, rctx->block_size) + rctx->block_size :
-                    length) > ASPEED_CRYPTO_SRC_DMA_BUF_LEN) {
-               dev_warn(hace_dev->dev, "Hash data length is too large\n");
-               return -EINVAL;
-       }
-
+       if (length > ASPEED_HASH_SRC_DMA_BUF_LEN)
+               length = ASPEED_HASH_SRC_DMA_BUF_LEN;
+       else if (rctx->flags & SHA_FLAGS_FINUP) {
+               if (round_up(length, rctx->block_size) + rctx->block_size >
+                   ASPEED_CRYPTO_SRC_DMA_BUF_LEN)
+                       length = round_down(length - 1, rctx->block_size);
+               else
+                       final = true;
+       } else
+               length -= remain;
        scatterwalk_map_and_copy(hash_engine->ahash_src_addr, rctx->src_sg,
-                                rctx->offset, rctx->total - remain, 0);
-       rctx->offset += rctx->total - remain;
+                                rctx->offset, length, 0);
+       rctx->offset += length;
 
-       rctx->digcnt[0] += rctx->total - remain;
-       if (rctx->digcnt[0] < rctx->total - remain)
+       rctx->digcnt[0] += length;
+       if (rctx->digcnt[0] < length)
                rctx->digcnt[1]++;
 
        if (final)
@@ -189,7 +193,7 @@ static int aspeed_ahash_dma_prepare(struct aspeed_hace_dev *hace_dev)
                return -ENOMEM;
        }
 
-       hash_engine->src_length = length - remain;
+       hash_engine->src_length = length;
        hash_engine->src_dma = hash_engine->ahash_src_dma_addr;
        hash_engine->digest_dma = rctx->digest_dma_addr;
 
@@ -385,6 +389,10 @@ static int aspeed_ahash_update_resume(struct aspeed_hace_dev *hace_dev)
        dma_unmap_single(hace_dev->dev, rctx->digest_dma_addr,
                         SHA512_DIGEST_SIZE, DMA_BIDIRECTIONAL);
 
+       if (rctx->total - rctx->offset >= rctx->block_size ||
+           (rctx->total != rctx->offset && rctx->flags & SHA_FLAGS_FINUP))
+               return aspeed_ahash_req_update(hace_dev);
+
        return aspeed_ahash_complete(hace_dev);
 }