cephfs: add read affinity mount option

This commit makes use of crush location labels from node
labels to supply `crush_location` and `read_from_replica=localize`
options during mount. Using these options, cephfs
will be able to redirect reads to the closest OSD,
improving performance.

Signed-off-by: Praveen M <m.praveen@ibm.com>

internal/csi-common/nodeserver-default.go

@@ -31,6 +31,10 @@ type DefaultNodeServer struct {
 	Driver  *CSIDriver
 	Type    string
 	Mounter mount.Interface
+	// NodeLabels stores the node labels
+	NodeLabels map[string]string
+	// CLIReadAffinityOptions contains map options passed through command line to enable read affinity.
+	CLIReadAffinityOptions string
 }
 
 // NodeGetInfo returns node ID.

internal/csi-common/utils.go

@@ -55,13 +55,18 @@ func NewVolumeCapabilityAccessMode(mode csi.VolumeCapability_AccessMode_Mode) *c
 }
 
 // NewDefaultNodeServer initializes default node server.
-func NewDefaultNodeServer(d *CSIDriver, t string, topology map[string]string) *DefaultNodeServer {
+func NewDefaultNodeServer(
+	d *CSIDriver, t, cliReadAffinityMapOptions string,
+	topology, nodeLabels map[string]string,
+) *DefaultNodeServer {
 	d.topology = topology
 
 	return &DefaultNodeServer{
-		Driver:  d,
-		Type:    t,
-		Mounter: mount.NewWithoutSystemd(""),
+		Driver:                 d,
+		Type:                   t,
+		Mounter:                mount.NewWithoutSystemd(""),
+		NodeLabels:             nodeLabels,
+		CLIReadAffinityOptions: cliReadAffinityMapOptions,
 	}
 }