[PATCH net] net: ti: am65-cpsw-switchdev: flush dynamic FDB entries by port on delete

[MD Danish Anwar <danishanwar@ti.com>]

On an FDB flush, dynamic ALE entries don't get deleted. They stay stale
until the ALE ages them out on its own ~30 seconds later. Two issues in the
DEL_TO_DEVICE handling cause this.

First, the delete was gated on the same "added_by_user" check used for
ADD, so every dynamic delete was dropped before reaching
cpsw_ale_del_ucast() at all. Drop that gate. Dynamic deletes are the only
way to remove a hardware-learned entry early; the ALE never reports upward
when it ages one out.

Second, dropping the gate alone isn't enough: ALE_VLAN_AWARE is always
on in switch mode, so a dynamic entry is stored under a real, nonzero
vid (possibly several, if the same MAC was learned on more than one
vid on a trunk port). With the bridge's vlan_filtering off, the bridge
core never learns the real vid and reports vid=0 on delete, so
cpsw_ale_del_ucast()'s exact (addr, vid) match never finds the row it
returns -ENOENT and the entry is left in place. For this vid=0-ambiguous
case, use a new cpsw_ale_del_ucast_dynamic_by_port() that matches by (addr,
port) instead of guessing one vid, clearing every dynamic row for that MAC
on that port regardless of vid.

Fixes: 86e8b070b25e ("net: ti: am65-cpsw-nuss: Add switchdev support")
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
---
 drivers/net/ethernet/ti/am65-cpsw-switchdev.c | 16 +++++++--
 drivers/net/ethernet/ti/cpsw_ale.c            | 36 ++++++++++++++++++-
 drivers/net/ethernet/ti/cpsw_ale.h            |  2 ++
 3 files changed, 50 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-switchdev.c b/drivers/net/ethernet/ti/am65-cpsw-switchdev.c
index 53cdac272b583..8b4640809cf5b 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-switchdev.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-switchdev.c
@@ -397,13 +397,23 @@ static void am65_cpsw_switchdev_event_work(struct work_struct *work)
 			   fdb->addr, fdb->vid, fdb->added_by_user,
 			   fdb->offloaded, port_id);
 
-		if (!fdb->added_by_user || fdb->is_local)
+		if (fdb->is_local)
 			break;
 		if (memcmp(port->slave.mac_addr, (u8 *)fdb->addr, ETH_ALEN) == 0)
 			port_id = HOST_PORT_NUM;
 
-		cpsw_ale_del_ucast(cpsw->ale, (u8 *)fdb->addr, port_id,
-				   fdb->vid ? ALE_VLAN : 0, fdb->vid);
+		if (!fdb->added_by_user && !fdb->vid)
+			/* vid=0 here just means "bridge doesn't know the
+			 * real vid" (vlan_filtering=0) -- the dynamic entry
+			 * may be stored under any nonzero vid, or several.
+			 * Delete by (addr, port) instead of guessing a vid.
+			 */
+			cpsw_ale_del_ucast_dynamic_by_port(cpsw->ale,
+							   (u8 *)fdb->addr,
+							   port_id);
+		else
+			cpsw_ale_del_ucast(cpsw->ale, (u8 *)fdb->addr, port_id,
+					   fdb->vid ? ALE_VLAN : 0, fdb->vid);
 		break;
 	default:
 		break;
diff --git a/drivers/net/ethernet/ti/cpsw_ale.c b/drivers/net/ethernet/ti/cpsw_ale.c
index e202bba494807..1a2aceda3dbe3 100644
--- a/drivers/net/ethernet/ti/cpsw_ale.c
+++ b/drivers/net/ethernet/ti/cpsw_ale.c
@@ -249,7 +249,7 @@ DEFINE_ALE_FIELD_SET(mcast_state,	62,	2)
 DEFINE_ALE_FIELD1(port_mask,		66)
 DEFINE_ALE_FIELD(super,			65,	1)
 DEFINE_ALE_FIELD(ucast_type,		62,     2)
-DEFINE_ALE_FIELD1_SET(port_num,		66)
+DEFINE_ALE_FIELD1(port_num,		66)
 DEFINE_ALE_FIELD_SET(blocked,		65,     1)
 DEFINE_ALE_FIELD_SET(secure,		64,     1)
 DEFINE_ALE_FIELD_GET(mcast,		40,	1)
@@ -441,6 +441,40 @@ static int cpsw_ale_find_ageable(struct cpsw_ale *ale)
 	return -ENOENT;
 }
 
+int cpsw_ale_del_ucast_dynamic_by_port(struct cpsw_ale *ale, const u8 *addr,
+				       int port)
+{
+	u32 ale_entry[ALE_ENTRY_WORDS];
+	int type, ucast_type, idx;
+	u8 entry_addr[6];
+	int deleted = 0;
+
+	for (idx = 0; idx < ale->params.ale_entries; idx++) {
+		cpsw_ale_read(ale, idx, ale_entry);
+		type = cpsw_ale_get_entry_type(ale_entry);
+		if (type != ALE_TYPE_ADDR && type != ALE_TYPE_VLAN_ADDR)
+			continue;
+		if (cpsw_ale_get_mcast(ale_entry))
+			continue;
+		ucast_type = cpsw_ale_get_ucast_type(ale_entry);
+		if (ucast_type == ALE_UCAST_PERSISTANT ||
+		    ucast_type == ALE_UCAST_OUI)
+			continue;
+		if (cpsw_ale_get_port_num(ale_entry, ale->port_num_bits) != port)
+			continue;
+		cpsw_ale_get_addr(ale_entry, entry_addr);
+		if (!ether_addr_equal(entry_addr, addr))
+			continue;
+
+		memset(ale_entry, 0, sizeof(ale_entry));
+		cpsw_ale_set_entry_type(ale_entry, ALE_TYPE_FREE);
+		cpsw_ale_write(ale, idx, ale_entry);
+		deleted++;
+	}
+
+	return deleted ? 0 : -ENOENT;
+}
+
 static void cpsw_ale_flush_mcast(struct cpsw_ale *ale, u32 *ale_entry,
 				 int port_mask)
 {
diff --git a/drivers/net/ethernet/ti/cpsw_ale.h b/drivers/net/ethernet/ti/cpsw_ale.h
index 87b7d1b3a34a9..69b004cbb1c76 100644
--- a/drivers/net/ethernet/ti/cpsw_ale.h
+++ b/drivers/net/ethernet/ti/cpsw_ale.h
@@ -166,6 +166,8 @@ int cpsw_ale_add_ucast(struct cpsw_ale *ale, const u8 *addr, int port,
 		       int flags, u16 vid);
 int cpsw_ale_del_ucast(struct cpsw_ale *ale, const u8 *addr, int port,
 		       int flags, u16 vid);
+int cpsw_ale_del_ucast_dynamic_by_port(struct cpsw_ale *ale, const u8 *addr,
+				       int port);
 int cpsw_ale_add_mcast(struct cpsw_ale *ale, const u8 *addr, int port_mask,
 		       int flags, u16 vid, int mcast_state);
 int cpsw_ale_del_mcast(struct cpsw_ale *ale, const u8 *addr, int port_mask,

base-commit: c9151088f1674fd29ff26a20f5fc687acf53a2f0
-- 
2.34.1