ice: Prevent ADQ, DCB coexistence with Custom Tx scheduler

ADQ, DCB might interfere with Custom Tx Scheduler changes that user
might introduce using devlink-rate API.

Check if ADQ, DCB is active, when user tries to change any setting
in exported Tx scheduler tree. If any of those are active block the user
from doing so, and log an appropriate message.

Remove the exported hierarchy if user enable ADQ or DCB.
Prevent ADQ or DCB from getting configured if user already made some
changes using devlink-rate API.

Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/intel/ice/ice_dcb_lib.c

@@ -3,6 +3,7 @@
 
 #include "ice_dcb_lib.h"
 #include "ice_dcb_nl.h"
+#include "ice_devlink.h"
 
 /**
  * ice_dcb_get_ena_tc - return bitmap of enabled TCs
@@ -364,6 +365,12 @@ int ice_pf_dcb_cfg(struct ice_pf *pf, struct ice_dcbx_cfg *new_cfg, bool locked)
 	/* Enable DCB tagging only when more than one TC */
 	if (ice_dcb_get_num_tc(new_cfg) > 1) {
 		dev_dbg(dev, "DCB tagging enabled (num TC > 1)\n");
+		if (pf->hw.port_info->is_custom_tx_enabled) {
+			dev_err(dev, "Custom Tx scheduler feature enabled, can't configure DCB\n");
+			return -EBUSY;
+		}
+		ice_tear_down_devlink_rate_tree(pf);
+
 		set_bit(ICE_FLAG_DCB_ENA, pf->flags);
 	} else {
 		dev_dbg(dev, "DCB tagging disabled (num TC = 1)\n");

drivers/net/ethernet/intel/ice/ice_devlink.c

@@ -8,6 +8,7 @@
 #include "ice_devlink.h"
 #include "ice_eswitch.h"
 #include "ice_fw_update.h"
+#include "ice_dcb_lib.h"
 
 static int ice_active_port_option = -1;
 
@@ -713,6 +714,63 @@ ice_devlink_port_unsplit(struct devlink *devlink, struct devlink_port *port,
 	return ice_devlink_port_split(devlink, port, 1, extack);
 }
 
+/**
+ * ice_tear_down_devlink_rate_tree - removes devlink-rate exported tree
+ * @pf: pf struct
+ *
+ * This function tears down tree exported during VF's creation.
+ */
+void ice_tear_down_devlink_rate_tree(struct ice_pf *pf)
+{
+	struct devlink *devlink;
+	struct ice_vf *vf;
+	unsigned int bkt;
+
+	devlink = priv_to_devlink(pf);
+
+	devl_lock(devlink);
+	mutex_lock(&pf->vfs.table_lock);
+	ice_for_each_vf(pf, bkt, vf) {
+		if (vf->devlink_port.devlink_rate)
+			devl_rate_leaf_destroy(&vf->devlink_port);
+	}
+	mutex_unlock(&pf->vfs.table_lock);
+
+	devl_rate_nodes_destroy(devlink);
+	devl_unlock(devlink);
+}
+
+/**
+ * ice_enable_custom_tx - try to enable custom Tx feature
+ * @pf: pf struct
+ *
+ * This function tries to enable custom Tx feature,
+ * it's not possible to enable it, if DCB or ADQ is active.
+ */
+static bool ice_enable_custom_tx(struct ice_pf *pf)
+{
+	struct ice_port_info *pi = ice_get_main_vsi(pf)->port_info;
+	struct device *dev = ice_pf_to_dev(pf);
+
+	if (pi->is_custom_tx_enabled)
+		/* already enabled, return true */
+		return true;
+
+	if (ice_is_adq_active(pf)) {
+		dev_err(dev, "ADQ active, can't modify Tx scheduler tree\n");
+		return false;
+	}
+
+	if (ice_is_dcb_active(pf)) {
+		dev_err(dev, "DCB active, can't modify Tx scheduler tree\n");
+		return false;
+	}
+
+	pi->is_custom_tx_enabled = true;
+
+	return true;
+}
+
 /**
  * ice_traverse_tx_tree - traverse Tx scheduler tree
  * @devlink: devlink struct
@@ -914,6 +972,9 @@ static int ice_devlink_rate_node_new(struct devlink_rate *rate_node, void **priv
 
 	pi = ice_get_pi_from_dev_rate(rate_node);
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_node->devlink)))
+		return -EBUSY;
+
 	/* preallocate memory for ice_sched_node */
 	node = devm_kzalloc(ice_hw_to_dev(pi->hw), sizeof(*node), GFP_KERNEL);
 	*priv = node;
@@ -934,6 +995,9 @@ static int ice_devlink_rate_node_del(struct devlink_rate *rate_node, void *priv,
 	if (!rate_node->parent || !node || tc_node == node || !extack)
 		return 0;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_node->devlink)))
+		return -EBUSY;
+
 	/* can't allow to delete a node with children */
 	if (node->num_children)
 		return -EINVAL;
@@ -950,6 +1014,9 @@ static int ice_devlink_rate_leaf_tx_max_set(struct devlink_rate *rate_leaf, void
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_leaf->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -962,6 +1029,9 @@ static int ice_devlink_rate_leaf_tx_share_set(struct devlink_rate *rate_leaf, vo
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_leaf->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -974,6 +1044,9 @@ static int ice_devlink_rate_leaf_tx_priority_set(struct devlink_rate *rate_leaf,
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_leaf->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -986,6 +1059,9 @@ static int ice_devlink_rate_leaf_tx_weight_set(struct devlink_rate *rate_leaf, v
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_leaf->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -998,6 +1074,9 @@ static int ice_devlink_rate_node_tx_max_set(struct devlink_rate *rate_node, void
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_node->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -1010,6 +1089,9 @@ static int ice_devlink_rate_node_tx_share_set(struct devlink_rate *rate_node, vo
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_node->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -1022,6 +1104,9 @@ static int ice_devlink_rate_node_tx_priority_set(struct devlink_rate *rate_node,
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_node->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -1034,6 +1119,9 @@ static int ice_devlink_rate_node_tx_weight_set(struct devlink_rate *rate_node, v
 {
 	struct ice_sched_node *node = priv;
 
+	if (!ice_enable_custom_tx(devlink_priv(rate_node->devlink)))
+		return -EBUSY;
+
 	if (!node)
 		return 0;
 
@@ -1059,6 +1147,9 @@ static int ice_devlink_set_parent(struct devlink_rate *devlink_rate,
 	if (!extack)
 		return 0;
 
+	if (!ice_enable_custom_tx(devlink_priv(devlink_rate->devlink)))
+		return -EBUSY;
+
 	if (!parent) {
 		if (!node || tc_node == node || node->num_children)
 			return -EINVAL;

drivers/net/ethernet/intel/ice/ice_devlink.h

@@ -19,5 +19,6 @@ void ice_devlink_init_regions(struct ice_pf *pf);
 void ice_devlink_destroy_regions(struct ice_pf *pf);
 
 int ice_devlink_rate_init_tx_topology(struct devlink *devlink, struct ice_vsi *vsi);
+void ice_tear_down_devlink_rate_tree(struct ice_pf *pf);
 
 #endif /* _ICE_DEVLINK_H_ */

drivers/net/ethernet/intel/ice/ice_main.c

@@ -8580,6 +8580,12 @@ static int ice_setup_tc_mqprio_qdisc(struct net_device *netdev, void *type_data)
 	switch (mode) {
 	case TC_MQPRIO_MODE_CHANNEL:
 
+		if (pf->hw.port_info->is_custom_tx_enabled) {
+			dev_err(dev, "Custom Tx scheduler feature enabled, can't configure ADQ\n");
+			return -EBUSY;
+		}
+		ice_tear_down_devlink_rate_tree(pf);
+
 		ret = ice_validate_mqprio_qopt(vsi, mqprio_qopt);
 		if (ret) {
 			netdev_err(netdev, "failed to validate_mqprio_qopt(), ret %d\n",

drivers/net/ethernet/intel/ice/ice_repr.c

@@ -6,6 +6,7 @@
 #include "ice_devlink.h"
 #include "ice_sriov.h"
 #include "ice_tc_lib.h"
+#include "ice_dcb_lib.h"
 
 /**
  * ice_repr_get_sw_port_id - get port ID associated with representor
@@ -426,6 +427,10 @@ int ice_repr_add_for_all_vfs(struct ice_pf *pf)
 			goto err;
 	}
 
+	/* only export if ADQ and DCB disabled */
+	if (ice_is_adq_active(pf) || ice_is_dcb_active(pf))
+		return 0;
+
 	devlink = priv_to_devlink(pf);
 	ice_devlink_rate_init_tx_topology(devlink, ice_get_main_vsi(pf));
 

drivers/net/ethernet/intel/ice/ice_type.h

@@ -715,6 +715,7 @@ struct ice_port_info {
 	struct ice_qos_cfg qos_cfg;
 	struct xarray sched_node_ids;
 	u8 is_vf:1;
+	u8 is_custom_tx_enabled:1;
 };
 
 struct ice_switch_info {