mlx4_core: Clean up error flow in mlx4_register_mac()

Fix a leak of entry if radix_tree_insert() fails.

Also, reduce the indentation and make the flow easier to read by
sticking to the conventional

    err = do_something();
    if (err)
            return err;

    err = do_another();
    if (err)
            return err;

rather than mixing the direction of the test as

    err = do_something();
    if (!err) {
            err = do_another();
            if (err)
                    return err;
    } else
            return err;

Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 17 insertions, 13 deletions

diff --git a/drivers/net/mlx4/port.c b/drivers/net/mlx4/port.c
index 609e0ec14cee..ef10113da356 100644
--- a/drivers/net/mlx4/port.c
+++ b/drivers/net/mlx4/port.c
@@ -148,22 +148,26 @@ int mlx4_register_mac(struct mlx4_dev *dev, u8 port, u64 mac, int *qpn, u8 wrap)
 
         if (dev->caps.flags & MLX4_DEV_CAP_FLAG_VEP_UC_STEER) {
                 err = mlx4_uc_steer_add(dev, port, mac, qpn, 1);
-                if (!err) {
-                        entry = kmalloc(sizeof *entry, GFP_KERNEL);
-                        if (!entry) {
-                                mlx4_uc_steer_release(dev, port, mac, *qpn, 1);
-                                return -ENOMEM;
-                        }
-                        entry->mac = mac;
-                        err = radix_tree_insert(&info->mac_tree, *qpn, entry);
-                        if (err) {
-                                mlx4_uc_steer_release(dev, port, mac, *qpn, 1);
-                                return err;
-                        }
-                } else
+                if (err)
                         return err;
+
+                entry = kmalloc(sizeof *entry, GFP_KERNEL);
+                if (!entry) {
+                        mlx4_uc_steer_release(dev, port, mac, *qpn, 1);
+                        return -ENOMEM;
+                }
+
+                entry->mac = mac;
+                err = radix_tree_insert(&info->mac_tree, *qpn, entry);
+                if (err) {
+                        kfree(entry);
+                        mlx4_uc_steer_release(dev, port, mac, *qpn, 1);
+                        return err;
+                }
         }
+
         mlx4_dbg(dev, "Registering MAC: 0x%llx\n", (unsigned long long) mac);
+
         mutex_lock(&table->mutex);
         for (i = 0; i < MLX4_MAX_MAC_NUM - 1; i++) {
                 if (free < 0 && !table->refs[i]) {