From d8fc13791a5c3944ab5f4a1c02e88a12c8f2ed67 Mon Sep 17 00:00:00 2001
From: Jeremy Xu <jeremyxu2010@gmail.com>
Date: Tue, 9 Jul 2019 23:29:02 +0800
Subject: [PATCH] Avoid RbdDiskManager's DetachDisk never execute again

---
 pkg/volume/rbd/attacher.go | 37 +++++++++++++++++++++++++++++--------
 pkg/volume/rbd/rbd_test.go | 31 +++++++++++++++++++++++++++++++
 pkg/volume/rbd/rbd_util.go | 18 ++++++++++++++++++
 3 files changed, 78 insertions(+), 8 deletions(-)

diff --git a/pkg/volume/rbd/attacher.go b/pkg/volume/rbd/attacher.go
index 8a05302a14bb..7dbb24b6685c 100644
--- a/pkg/volume/rbd/attacher.go
+++ b/pkg/volume/rbd/attacher.go
@@ -216,18 +216,39 @@ func (detacher *rbdDetacher) UnmountDevice(deviceMountPath string) error {
 		return err
 	}
 	// Unmount the device from the device mount point.
-	klog.V(4).Infof("rbd: unmouting device mountpoint %s", deviceMountPath)
-	if err = detacher.mounter.Unmount(deviceMountPath); err != nil {
+	notMnt, err := detacher.mounter.IsLikelyNotMountPoint(deviceMountPath)
+	if err != nil {
 		return err
 	}
-	klog.V(3).Infof("rbd: successfully umount device mountpath %s", deviceMountPath)
+	if !notMnt {
+		klog.V(4).Infof("rbd: unmouting device mountpoint %s", deviceMountPath)
+		if err = detacher.mounter.Unmount(deviceMountPath); err != nil {
+			return err
+		}
+		klog.V(3).Infof("rbd: successfully umount device mountpath %s", deviceMountPath)
+	}
 
-	klog.V(4).Infof("rbd: detaching device %s", devicePath)
-	err = detacher.manager.DetachDisk(detacher.plugin, deviceMountPath, devicePath)
-	if err != nil {
-		return err
+	// Get devicePath from deviceMountPath if devicePath is empty
+	if devicePath == "" {
+		rbdImageInfo, err := getRbdImageInfo(deviceMountPath)
+		if err != nil {
+			return err
+		}
+		found := false
+		devicePath, found = getRbdDevFromImageAndPool(rbdImageInfo.pool, rbdImageInfo.name)
+		if !found {
+			klog.Warningf("rbd: can't found devicePath for %v. Device is already unmounted, Image %v, Pool %v", deviceMountPath, rbdImageInfo.pool, rbdImageInfo.name)
+		}
+	}
+
+	if devicePath != "" {
+		klog.V(4).Infof("rbd: detaching device %s", devicePath)
+		err = detacher.manager.DetachDisk(detacher.plugin, deviceMountPath, devicePath)
+		if err != nil {
+			return err
+		}
+		klog.V(3).Infof("rbd: successfully detach device %s", devicePath)
 	}
-	klog.V(3).Infof("rbd: successfully detach device %s", devicePath)
 	err = os.Remove(deviceMountPath)
 	if err != nil {
 		return err
diff --git a/pkg/volume/rbd/rbd_test.go b/pkg/volume/rbd/rbd_test.go
index 4e133d1d551e..e792696def8d 100644
--- a/pkg/volume/rbd/rbd_test.go
+++ b/pkg/volume/rbd/rbd_test.go
@@ -707,3 +707,34 @@ func TestGetRbdImageSize(t *testing.T) {
 		}
 	}
 }
+
+func TestGetRbdImageInfo(t *testing.T) {
+	tmpDir, err := utiltesting.MkTmpdir("rbd_test")
+	if err != nil {
+		t.Fatalf("error creating temp dir: %v", err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	for i, c := range []struct {
+		DeviceMountPath    string
+		TargetRbdImageInfo *rbdImageInfo
+	}{
+		{
+			DeviceMountPath:    fmt.Sprintf("%s/plugins/kubernetes.io/rbd/rbd/pool1-image-image1", tmpDir),
+			TargetRbdImageInfo: &rbdImageInfo{pool: "pool1", name: "image1"},
+		},
+		{
+			DeviceMountPath:    fmt.Sprintf("%s/plugins/kubernetes.io/rbd/mounts/pool2-image-image2", tmpDir),
+			TargetRbdImageInfo: &rbdImageInfo{pool: "pool2", name: "image2"},
+		},
+	} {
+		rbdImageInfo, err := getRbdImageInfo(c.DeviceMountPath)
+		if err != nil {
+			t.Errorf("Case %d: getRbdImageInfo failed: %v", i, err)
+			continue
+		}
+		if !reflect.DeepEqual(rbdImageInfo, c.TargetRbdImageInfo) {
+			t.Errorf("Case %d: unexpected RbdImageInfo, wanted %v, got %v", i, c.TargetRbdImageInfo, rbdImageInfo)
+		}
+	}
+}
diff --git a/pkg/volume/rbd/rbd_util.go b/pkg/volume/rbd/rbd_util.go
index a83a0212fc46..a314821ef9b4 100644
--- a/pkg/volume/rbd/rbd_util.go
+++ b/pkg/volume/rbd/rbd_util.go
@@ -57,6 +57,12 @@ const (
 	rbdImageSizeUnitMiB      = 1024 * 1024
 )
 
+// A struct contains rbd image info.
+type rbdImageInfo struct {
+	pool string
+	name string
+}
+
 func getDevFromImageAndPool(pool, image string) (string, bool) {
 	device, found := getRbdDevFromImageAndPool(pool, image)
 	if found {
@@ -789,3 +795,15 @@ func (util *RBDUtil) rbdStatus(b *rbdMounter) (bool, string, error) {
 		return false, output, nil
 	}
 }
+
+// getRbdImageInfo try to get rbdImageInfo from deviceMountPath.
+func getRbdImageInfo(deviceMountPath string) (*rbdImageInfo, error) {
+	deviceMountedPathSeps := strings.Split(filepath.Base(deviceMountPath), "-image-")
+	if len(deviceMountedPathSeps) != 2 {
+		return nil, fmt.Errorf("Can't found devicePath for %s ", deviceMountPath)
+	}
+	return &rbdImageInfo{
+		pool: deviceMountedPathSeps[0],
+		name: deviceMountedPathSeps[1],
+	}, nil
+}