cephfs: upgrading mount syntax

The old syntax is almost deprecated,and there are reasons to upgrade it
 - old syntax is lack of fsid(critical for debugging and observability)
 - mds_namespace is deprecated, it might be inappropriate to continue using it
 - kernel will try new syntax first and then the old one, it's a waste

Signed-off-by: mageekchiu <[email protected]>

Author: MageekChiu

internal/cephfs/mounter/kernel.go

@@ -74,16 +74,13 @@ func (m *kernelMounter) mountKernel(
 
 	args := []string{
 		"-t", "ceph",
-		fmt.Sprintf("%s:%s", volOptions.Monitors, volOptions.RootPath),
+		fmt.Sprintf("%s@%s.%s=%s", cr.ID, volOptions.ClusterID, volOptions.FsName, volOptions.RootPath),
 		mountPoint,
 	}
 
-	optionsStr := fmt.Sprintf("name=%s,secretfile=%s", cr.ID, cr.KeyFile)
-	mdsNamespace := ""
-	if volOptions.FsName != "" {
-		mdsNamespace = "mds_namespace=" + volOptions.FsName
-	}
-	optionsStr = util.MountOptionsAdd(optionsStr, mdsNamespace, volOptions.KernelMountOptions, netDev)
+	optionsStr := fmt.Sprintf("mon_addr=%s,secretfile=%s", strings.ReplaceAll(volOptions.Monitors, ",", "/"), cr.KeyFile)
+
+	optionsStr = util.MountOptionsAdd(optionsStr, volOptions.KernelMountOptions, netDev)
 
 	args = append(args, "-o", optionsStr)