[PATCH net-next 01/12] net/mlx5: E-switch, refactor eswitch mode change

[Tariq Toukan <tariqt@nvidia.com>]

From: Patrisious Haddad <phaddad@nvidia.com>

The E-switch mode was previously updated before removing and re-adding the
IB device, which could cause a temporary mismatch between the E-switch mode
and the IB device configuration.

To prevent this discrepancy, the IB device is now removed first, then
the E-switch mode is updated, and finally, the IB device is re-added.
This sequence ensures consistent alignment between the E-switch mode and
the IB device whenever the mode changes, regardless of the new mode value.

Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 .../net/ethernet/mellanox/mlx5/core/eswitch.c |  1 -
 .../mellanox/mlx5/core/eswitch_offloads.c     | 26 +++++++++++++++----
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index cead41ddbc38..d0dab8f4e1a3 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -1490,7 +1490,6 @@ int mlx5_eswitch_enable_locked(struct mlx5_eswitch *esw, int num_vfs)
 	if (esw->mode == MLX5_ESWITCH_LEGACY) {
 		err = esw_legacy_enable(esw);
 	} else {
-		mlx5_rescan_drivers(esw->dev);
 		err = esw_offloads_enable(esw);
 	}
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index fd34f43d18d5..5f1adebd9669 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -2332,18 +2332,35 @@ static int esw_create_restore_table(struct mlx5_eswitch *esw)
 	return err;
 }
 
+static void esw_mode_change(struct mlx5_eswitch *esw, u16 mode)
+{
+	mlx5_devcom_comp_lock(esw->dev->priv.hca_devcom_comp);
+
+	if (esw->dev->priv.flags & MLX5_PRIV_FLAGS_DISABLE_IB_ADEV) {
+		esw->mode = mode;
+		mlx5_devcom_comp_unlock(esw->dev->priv.hca_devcom_comp);
+		return;
+	}
+
+	esw->dev->priv.flags |= MLX5_PRIV_FLAGS_DISABLE_IB_ADEV;
+	mlx5_rescan_drivers_locked(esw->dev);
+	esw->mode = mode;
+	esw->dev->priv.flags &= ~MLX5_PRIV_FLAGS_DISABLE_IB_ADEV;
+	mlx5_rescan_drivers_locked(esw->dev);
+	mlx5_devcom_comp_unlock(esw->dev->priv.hca_devcom_comp);
+}
+
 static int esw_offloads_start(struct mlx5_eswitch *esw,
 			      struct netlink_ext_ack *extack)
 {
 	int err;
 
-	esw->mode = MLX5_ESWITCH_OFFLOADS;
+	esw_mode_change(esw, MLX5_ESWITCH_OFFLOADS);
 	err = mlx5_eswitch_enable_locked(esw, esw->dev->priv.sriov.num_vfs);
 	if (err) {
 		NL_SET_ERR_MSG_MOD(extack,
 				   "Failed setting eswitch to offloads");
-		esw->mode = MLX5_ESWITCH_LEGACY;
-		mlx5_rescan_drivers(esw->dev);
+		esw_mode_change(esw, MLX5_ESWITCH_LEGACY);
 		return err;
 	}
 	if (esw->offloads.inline_mode == MLX5_INLINE_MODE_NONE) {
@@ -3584,7 +3601,7 @@ static int esw_offloads_stop(struct mlx5_eswitch *esw,
 {
 	int err;
 
-	esw->mode = MLX5_ESWITCH_LEGACY;
+	esw_mode_change(esw, MLX5_ESWITCH_LEGACY);
 
 	/* If changing from switchdev to legacy mode without sriov enabled,
 	 * no need to create legacy fdb.
@@ -3770,7 +3787,6 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 		err = esw_offloads_start(esw, extack);
 	} else if (mode == DEVLINK_ESWITCH_MODE_LEGACY) {
 		err = esw_offloads_stop(esw, extack);
-		mlx5_rescan_drivers(esw->dev);
 	} else {
 		err = -EINVAL;
 	}
-- 
2.44.0