rbd: add hardlimt and softlimit flag

added Hardlimit and Softlimit flags for cephcsi
arguments. When the Softlimit is reached cephcsi
will start a background task to flatten the rbd
image and return success and if the hardlimit
is reached it will start a background task
to flatten the rbd image and return ready
to use as false to make sure that the image
will not be used until it is flatten.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

charts/ceph-csi-rbd/templates/provisioner-deployment.yaml

@@ -114,6 +114,8 @@ spec:
             - "--endpoint=$(CSI_ENDPOINT)"
             - "--v=5"
             - "--drivername=$(DRIVER_NAME)"
+            - "--rbdhardmaxclonedepth={{ .Values.provisioner.hardMaxCloneDepth }}"
+            - "--rbdsoftmaxclonedepth={{ .Values.provisioner.softMaxCloneDepth }}"
           env:
             - name: POD_IP
               valueFrom:

charts/ceph-csi-rbd/values.yaml

@@ -107,6 +107,12 @@ provisioner:
   replicaCount: 3
   # Timeout for waiting for creation or deletion of a volume
   timeout: 60s
+  # Hard limit for maximum number of nested volume clones that are taken before
+  # a flatten occurs
+  hardMaxCloneDepth: 8
+  # Soft limit for maximum number of nested volume clones that are taken before
+  # a flatten occurs
+  softMaxCloneDepth: 4
 
   httpMetrics:
     # Metrics only available for cephcsi/cephcsi => 1.2.0