Re: [PATCH 2/6] crypto: ccp - Remove unneeded sign-extension support

The reverse-get/set functions can be simplified by
eliminating unused code.


Signed-off-by: Gary R Hook <redacted>
---
 drivers/crypto/ccp/ccp-ops.c |  145 +++++++++++++++++-------------------------
 1 file changed, 59 insertions(+), 86 deletions(-)

diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
index 8fedb14..82cc637 100644
--- a/drivers/crypto/ccp/ccp-ops.c
+++ b/drivers/crypto/ccp/ccp-ops.c

@@ -198,62 +198,46 @@ static void ccp_get_dm_area(struct ccp_dm_workarea *wa, unsigned int wa_offset,
 }
 
 static int ccp_reverse_set_dm_area(struct ccp_dm_workarea *wa,
+				   unsigned int wa_offset,
 				   struct scatterlist *sg,
-				   unsigned int len, unsigned int se_len,
-				   bool sign_extend)
+				   unsigned int sg_offset,
+				   unsigned int len)
 {
-	unsigned int nbytes, sg_offset, dm_offset, sb_len, i;
-	u8 buffer[CCP_REVERSE_BUF_SIZE];
-
-	if (WARN_ON(se_len > sizeof(buffer)))
-		return -EINVAL;
-
-	sg_offset = len;
-	dm_offset = 0;
-	nbytes = len;
-	while (nbytes) {
-		sb_len = min_t(unsigned int, nbytes, se_len);
-		sg_offset -= sb_len;
-
-		scatterwalk_map_and_copy(buffer, sg, sg_offset, sb_len, 0);
-		for (i = 0; i < sb_len; i++)
-			wa->address[dm_offset + i] = buffer[sb_len - i - 1];
-
-		dm_offset += sb_len;
-		nbytes -= sb_len;
-
-		if ((sb_len != se_len) && sign_extend) {
-			/* Must sign-extend to nearest sign-extend length */
-			if (wa->address[dm_offset - 1] & 0x80)
-				memset(wa->address + dm_offset, 0xff,
-				       se_len - sb_len);
-		}
+	u8 *p, *q;
+
+	ccp_set_dm_area(wa, wa_offset, sg, sg_offset, len);
+
+	p = wa->address + wa_offset;
+	q = p + len - 1;
+	while (p < q) {
+		*p = *p ^ *q;
+		*q = *p ^ *q;
+		*p = *p ^ *q;
+		p++;
+		q--;
 	}
-
 	return 0;
 }
 
 static void ccp_reverse_get_dm_area(struct ccp_dm_workarea *wa,
+				    unsigned int wa_offset,
 				    struct scatterlist *sg,
+				    unsigned int sg_offset,
 				    unsigned int len)
 {
-	unsigned int nbytes, sg_offset, dm_offset, sb_len, i;
-	u8 buffer[CCP_REVERSE_BUF_SIZE];
-
-	sg_offset = 0;
-	dm_offset = len;
-	nbytes = len;
-	while (nbytes) {
-		sb_len = min_t(unsigned int, nbytes, sizeof(buffer));
-		dm_offset -= sb_len;
-
-		for (i = 0; i < sb_len; i++)
-			buffer[sb_len - i - 1] = wa->address[dm_offset + i];
-		scatterwalk_map_and_copy(buffer, sg, sg_offset, sb_len, 1);
-
-		sg_offset += sb_len;
-		nbytes -= sb_len;
+	u8 *p, *q;
+
+	p = wa->address + wa_offset;
+	q = p + len - 1;
+	while (p < q) {
+		*p = *p ^ *q;
+		*q = *p ^ *q;
+		*p = *p ^ *q;
+		p++;
+		q--;
 	}
+
+	ccp_get_dm_area(wa, wa_offset, sg, sg_offset, len);
 }
 
 static void ccp_free_data(struct ccp_data *data, struct ccp_cmd_queue *cmd_q)

@@ -1294,7 +1278,9 @@ static int ccp_run_rsa_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 	struct ccp_data dst;
 	struct ccp_op op;
 	unsigned int sb_count, i_len, o_len;
-	int ret;
+	unsigned int dm_offset;
+	int i = 0;