mlx4: decreasing ref count when removing mac

For older FW versions, when a Mac address removed from Mac table,
we should set 0 for reference count for the corresponding Mac index.
Fixes a bug where removing Mac from the table still left that entry as
invalid.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Tested-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/net/mlx4/port.c b/drivers/net/mlx4/port.c
index 1f95afda6841..609e0ec14cee 100644
--- a/drivers/net/mlx4/port.c
+++ b/drivers/net/mlx4/port.c
@@ -258,9 +258,12 @@ void mlx4_unregister_mac(struct mlx4_dev *dev, u8 port, int qpn)
         if (validate_index(dev, table, index))
                 goto out;
 
-        table->entries[index] = 0;
-        mlx4_set_port_mac_table(dev, port, table->entries);
-        --table->total;
+        /* Check whether this address has reference count */
+        if (!(--table->refs[index])) {
+                table->entries[index] = 0;
+                mlx4_set_port_mac_table(dev, port, table->entries);
+                --table->total;
+        }
 out:
         mutex_unlock(&table->mutex);
 }