From 579dd378f74f85e3e9ff3fb8c36e0c744e27c3ef Mon Sep 17 00:00:00 2001
From: Benjamin Isinger <Benjamin.Isinger@ibm.com>
Date: Fri, 9 May 2025 17:10:14 +0200
Subject: [PATCH] Add support to configure MaxVolumesPerNode for of csi node

Add support to configure MaxVolumesPerNode setting of csi node via the cos-csi-driver-configmap.
The configmap value will be synced to the CR
The node syncer will then update the MAX_VOLUMES_PER_NODE env var on the daemonset

Depends on https://github.com/IBM/ibm-object-csi-driver/pull/173

Signed-off-by: Benjamin Isinger <Benjamin.Isinger@ibm.com>
---
 api/v1alpha1/ibmobjectcsi_types.go     |  3 +++
 controllers/ibmobjectcsi_controller.go | 14 ++++++++++----
 controllers/syncer/csi_node.go         | 11 ++++++++++-
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/api/v1alpha1/ibmobjectcsi_types.go b/api/v1alpha1/ibmobjectcsi_types.go
index 33ef1d5..190622a 100644
--- a/api/v1alpha1/ibmobjectcsi_types.go
+++ b/api/v1alpha1/ibmobjectcsi_types.go
@@ -69,6 +69,9 @@ type IBMObjectCSINodeSpec struct {
 	Tolerations []corev1.Toleration `json:"tolerations,omitempty"`
 
 	Resources ResourcesSpec `json:"resources,omitempty"`
+
+	// +kubebuilder:validation:Optional
+	MaxVolumesPerNode string `json:"maxVolumesPerNode,omitempty"`
 }
 
 // IBMObjectCSIControllerSpec defines the desired state of IBMObjectCSIController
diff --git a/controllers/ibmobjectcsi_controller.go b/controllers/ibmobjectcsi_controller.go
index d7ce78d..a25f485 100644
--- a/controllers/ibmobjectcsi_controller.go
+++ b/controllers/ibmobjectcsi_controller.go
@@ -222,10 +222,15 @@ func (r *IBMObjectCSIReconciler) handleConfigMapReconcile(ctx context.Context, r
 	CSINodeMemoryRequest := configMap.Data["CSINodeMemoryRequest"]
 	CSINodeCPULimit := configMap.Data["CSINodeCPULimit"]
 	CSINodeMemoryLimit := configMap.Data["CSINodeMemoryLimit"]
+	CSINodeMaxVolumesPerNode := configMap.Data["CSINodeMaxVolumesPerNode"]
 
-	reqLogger.Info("The resource requests and limits fetched from configmap",
-		"CSINodeCPURequest", CSINodeCPURequest, "CSINodeMemoryRequest", CSINodeMemoryRequest,
-		"CSINodeCPULimit", CSINodeCPULimit, "CSINodeMemoryLimit", CSINodeMemoryLimit)
+	reqLogger.Info("Configruration fetched from configmap",
+		"CSINodeCPURequest", CSINodeCPURequest,
+		"CSINodeMemoryRequest", CSINodeMemoryRequest,
+		"CSINodeCPULimit", CSINodeCPULimit,
+		"CSINodeMemoryLimit", CSINodeMemoryLimit,
+		"CSINodeMaxVolumesPerNode", CSINodeMaxVolumesPerNode,
+	)
 
 	// Fetch the IBMObjectCSI instance
 	instance := &objectdriverv1alpha1.IBMObjectCSI{}
@@ -245,9 +250,10 @@ func (r *IBMObjectCSIReconciler) handleConfigMapReconcile(ctx context.Context, r
 	instance.Spec.Node.Resources.Requests.Memory = CSINodeMemoryRequest
 	instance.Spec.Node.Resources.Limits.CPU = CSINodeCPULimit
 	instance.Spec.Node.Resources.Limits.Memory = CSINodeMemoryLimit
+	instance.Spec.Node.MaxVolumesPerNode = CSINodeMaxVolumesPerNode
 
 	// Update the instance in the Kubernetes API server
-	reqLogger.Info("Updating IBMObjectCSI CR with resource requests and limits for Node pods")
+	reqLogger.Info("Updating IBMObjectCSI CR with ConfigMap values")
 	err = r.Update(ctx, instance)
 	if err != nil {
 		reqLogger.Error(err, "Failed to update IBMObjectCSI instance with ConfigMap values")
diff --git a/controllers/syncer/csi_node.go b/controllers/syncer/csi_node.go
index 21c96cb..6b66c99 100644
--- a/controllers/syncer/csi_node.go
+++ b/controllers/syncer/csi_node.go
@@ -212,7 +212,7 @@ func envVarFromField(name, fieldPath string) corev1.EnvVar {
 func (s *csiNodeSyncer) getEnvFor(name string) []corev1.EnvVar {
 	switch name {
 	case constants.NodeContainerName:
-		return []corev1.EnvVar{
+		envVars := []corev1.EnvVar{
 			{
 				Name:  "CSI_ENDPOINT",
 				Value: constants.CSINodeEndpoint,
@@ -220,6 +220,15 @@ func (s *csiNodeSyncer) getEnvFor(name string) []corev1.EnvVar {
 			envVarFromField("KUBE_NODE_NAME", "spec.nodeName"),
 		}
 
+		if s.driver.Spec.Node.MaxVolumesPerNode != "" {
+			envVars = append(envVars, corev1.EnvVar{
+				Name:  "MAX_VOLUMES_PER_NODE",
+				Value: s.driver.Spec.Node.MaxVolumesPerNode,
+			})
+		}
+
+		return envVars
+
 	case constants.CSINodeDriverRegistrar:
 		return []corev1.EnvVar{
 			{