crypto: inside-secure: back out parts of earlier HMAC update workaround

This patch backs out some changes done with commit 082ec2d -
"add support for HMAC updates" as that update just works around the
issue for the basic tests by providing twice the amount of buffering,
but this does not solve the case of much larger data blocks such as
those performed by the extra tests.
This is in preparation of an actual solution in the next patch(es),
which does not actually require any extra buffering at all.

Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/inside-secure/safexcel_hash.c

@@ -41,11 +41,11 @@ struct safexcel_ahash_req {
 	u64 len[2];
 	u64 processed[2];
 
-	u8 cache[SHA512_BLOCK_SIZE << 1] __aligned(sizeof(u32));
+	u8 cache[SHA512_BLOCK_SIZE] __aligned(sizeof(u32));
 	dma_addr_t cache_dma;
 	unsigned int cache_sz;
 
-	u8 cache_next[SHA512_BLOCK_SIZE << 1] __aligned(sizeof(u32));
+	u8 cache_next[SHA512_BLOCK_SIZE] __aligned(sizeof(u32));
 };
 
 static inline u64 safexcel_queued_len(struct safexcel_ahash_req *req)
@@ -89,9 +89,6 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx,
 	cdesc->control_data.control0 |= ctx->alg;
 	cdesc->control_data.control0 |= req->digest;
 
-	if (!req->finish)
-		cdesc->control_data.control0 |= CONTEXT_CONTROL_NO_FINISH_HASH;
-
 	if (req->digest == CONTEXT_CONTROL_DIGEST_PRECOMPUTED) {
 		if (req->processed[0] || req->processed[1]) {
 			if (ctx->alg == CONTEXT_CONTROL_CRYPTO_ALG_MD5)
@@ -110,6 +107,9 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx,
 			cdesc->control_data.control0 |= CONTEXT_CONTROL_RESTART_HASH;
 		}
 
+		if (!req->finish)
+			cdesc->control_data.control0 |= CONTEXT_CONTROL_NO_FINISH_HASH;
+
 		/*
 		 * Copy the input digest if needed, and setup the context
 		 * fields. Do this now as we need it to setup the first command
@@ -216,8 +216,6 @@ static int safexcel_ahash_send_req(struct crypto_async_request *async, int ring,
 	u64 queued, len, cache_len, cache_max;
 
 	cache_max = crypto_ahash_blocksize(ahash);
-	if (req->digest == CONTEXT_CONTROL_DIGEST_HMAC)
-		cache_max <<= 1;
 
 	queued = len = safexcel_queued_len(req);
 	if (queued <= cache_max)
@@ -229,24 +227,26 @@ static int safexcel_ahash_send_req(struct crypto_async_request *async, int ring,
 		/* If this is not the last request and the queued data does not
 		 * fit into full blocks, cache it for the next send() call.
 		 */
-		extra = queued & (crypto_ahash_blocksize(ahash) - 1);
-
-		if (req->digest == CONTEXT_CONTROL_DIGEST_HMAC &&
-		    extra < crypto_ahash_blocksize(ahash))
-			extra += crypto_ahash_blocksize(ahash);
+		extra = queued & (cache_max - 1);
 
 		/* If this is not the last request and the queued data
 		 * is a multiple of a block, cache the last one for now.
 		 */
 		if (!extra)
-			extra = crypto_ahash_blocksize(ahash);
+			extra = cache_max;
 
 		sg_pcopy_to_buffer(areq->src, sg_nents(areq->src),
 				   req->cache_next, extra,
 				   areq->nbytes - extra);
 
 		queued -= extra;
 		len -= extra;
+
+		if (!queued) {
+			*commands = 0;
+			*results = 0;
+			return 0;
+		}
 	}
 
 	/* Add a command descriptor for the cached data, if any */
@@ -613,8 +613,6 @@ static int safexcel_ahash_update(struct ahash_request *areq)
 		req->len[1]++;
 
 	cache_max = crypto_ahash_blocksize(ahash);
-	if (req->digest == CONTEXT_CONTROL_DIGEST_HMAC)
-		cache_max <<= 1;
 
 	safexcel_ahash_cache(areq, cache_max);
 
@@ -689,8 +687,6 @@ static int safexcel_ahash_export(struct ahash_request *areq, void *out)
 	u32 cache_sz;
 
 	cache_sz = crypto_ahash_blocksize(ahash);
-	if (req->digest == CONTEXT_CONTROL_DIGEST_HMAC)
-		cache_sz <<= 1;
 
 	export->len[0] = req->len[0];
 	export->len[1] = req->len[1];
@@ -718,8 +714,6 @@ static int safexcel_ahash_import(struct ahash_request *areq, const void *in)
 		return ret;
 
 	cache_sz = crypto_ahash_blocksize(ahash);
-	if (req->digest == CONTEXT_CONTROL_DIGEST_HMAC)
-		cache_sz <<= 1;
 
 	req->len[0] = export->len[0];
 	req->len[1] = export->len[1];