[PATCH net-next 04/10] net: microchip: sparx5: Use chain ids without offsets when enabling rules

[Steen Hegelund]

This improves the check performed on linked rules when enabling or
disabling them.  The chain id used must be the chain id without the offset
used for linking the rules.

Signed-off-by: Steen Hegelund <steen.hegelund at microchip.com>
---
 .../net/ethernet/microchip/vcap/vcap_api.c    | 21 ++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api.c b/drivers/net/ethernet/microchip/vcap/vcap_api.c
index 68e04d47f6fd..9ca0cb855c3c 100644
--- a/drivers/net/ethernet/microchip/vcap/vcap_api.c
+++ b/drivers/net/ethernet/microchip/vcap/vcap_api.c
@@ -1568,6 +1568,18 @@ static int vcap_write_counter(struct vcap_rule_internal *ri,
 	return 0;
 }
 
+/* Return the chain id rounded down to nearest lookup */
+static int vcap_round_down_chain(int cid)
+{
+	return cid - (cid % VCAP_CID_LOOKUP_SIZE);
+}
+
+/* Return the chain id rounded up to nearest lookup */
+static int vcap_round_up_chain(int cid)
+{
+	return vcap_round_down_chain(cid + VCAP_CID_LOOKUP_SIZE);
+}
+
 /* Convert a chain id to a VCAP lookup index */
 int vcap_chain_id_to_lookup(struct vcap_admin *admin, int cur_cid)
 {
@@ -1650,9 +1662,7 @@ bool vcap_is_next_lookup(struct vcap_control *vctrl, int src_cid, int dst_cid)
 		return false;
 
 	/* The offset must be at least one lookup, round up */
-	next_cid = src_cid + VCAP_CID_LOOKUP_SIZE;
-	next_cid /= VCAP_CID_LOOKUP_SIZE;
-	next_cid *= VCAP_CID_LOOKUP_SIZE;
+	next_cid = vcap_round_up_chain(src_cid);
 
 	if (dst_cid < next_cid)
 		return false;
@@ -2177,12 +2187,13 @@ static int vcap_get_next_chain(struct vcap_control *vctrl,
 static bool vcap_path_exist(struct vcap_control *vctrl, struct net_device *ndev,
 			    int dst_cid)
 {
+	int cid = vcap_round_down_chain(dst_cid);
 	struct vcap_enabled_port *eport = NULL;
 	struct vcap_enabled_port *elem;
 	struct vcap_admin *admin;
 	int tmp;
 
-	if (dst_cid == 0) /* Chain zero is always available */
+	if (cid == 0) /* Chain zero is always available */
 		return true;
 
 	/* Find first entry that starts from chain 0*/
@@ -2201,7 +2212,7 @@ static bool vcap_path_exist(struct vcap_control *vctrl, struct net_device *ndev,
 		return false;
 
 	tmp = eport->dst_cid;
-	while (tmp != dst_cid && tmp != 0)
+	while (tmp != cid && tmp != 0)
 		tmp = vcap_get_next_chain(vctrl, ndev, tmp);
 
 	return !!tmp;
-- 
2.39.1