Merge pull request #63270 from andyzhangx/volume-partition-azure-fix

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fix data loss issue if using existing azure disk with partitions in disk mount 

**What this PR does / why we need it**:
When use an existing azure disk(also called [static provisioning](https://github.com/andyzhangx/demo/tree/master/linux/azuredisk#static-provisioning-for-azure-disk)) in pod, if that disk has multiple partitions, the disk will be formatted in the pod mounting.

This PR removes `formatIfNotFormatted` func in `WaitForAttach` which uses `lsblk` command to check whether disk is formatted or not
b87a392b1a/pkg/volume/azure_dd/azure_common_linux.go (L213-L215)

And finally the format disk operation will happen in `MountDevice` in which it uses common k8s code(`SafeFormatAndMount.GetDiskFormat`) using `blkid` to detect disk format, `blkid` could detect multiple partitions
b87a392b1a/pkg/util/mount/mount_linux.go (L541-L543)

 - so if we use common k8s code(`SafeFormatAndMount.GetDiskFormat`), following error will be returned for mulitple partition disks, which is expected:

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #63235

**Special notes for your reviewer**:
This PR depends on https://github.com/kubernetes/kubernetes/pull/63248

**Release note**:

```
fix data loss issue if using existing azure disk with partitions in disk mount 
```

/sig azure
/assign @khenidak

pkg/volume/azure_dd/attacher.go

@@ -185,10 +185,6 @@ func (a *azureDiskAttacher) WaitForAttach(spec *volume.Spec, devicePath string,
 
 		// did we find it?
 		if newDevicePath != "" {
-			// the current sequence k8s uses for unformated disk (check-disk, mount, fail, mkfs.extX) hangs on
-			// Azure Managed disk scsi interface. this is a hack and will be replaced once we identify and solve
-			// the root case on Azure.
-			formatIfNotFormatted(newDevicePath, *volumeSource.FSType, exec)
 			return true, nil
 		}
 

pkg/volume/azure_dd/azure_common_linux.go

@@ -178,45 +178,3 @@ func findDiskByLunWithConstraint(lun int, io ioHandler, azureDisks []string) (st
 	}
 	return "", err
 }
-
-func formatIfNotFormatted(disk string, fstype string, exec mount.Exec) {
-	notFormatted, err := diskLooksUnformatted(disk, exec)
-	if err == nil && notFormatted {
-		args := []string{disk}
-		// Disk is unformatted so format it.
-		// Use 'ext4' as the default
-		if len(fstype) == 0 {
-			fstype = "ext4"
-		}
-		if fstype == "ext4" || fstype == "ext3" {
-			args = []string{"-E", "lazy_itable_init=0,lazy_journal_init=0", "-F", disk}
-		}
-		glog.Infof("azureDisk - Disk %q appears to be unformatted, attempting to format as type: %q with options: %v", disk, fstype, args)
-
-		_, err := exec.Run("mkfs."+fstype, args...)
-		if err == nil {
-			// the disk has been formatted successfully try to mount it again.
-			glog.Infof("azureDisk - Disk successfully formatted with 'mkfs.%s %v'", fstype, args)
-		} else {
-			glog.Warningf("azureDisk - Error formatting volume with 'mkfs.%s %v': %v", fstype, args, err)
-		}
-	} else {
-		if err != nil {
-			glog.Warningf("azureDisk - Failed to check if the disk %s formatted with error %s, will attach anyway", disk, err)
-		} else {
-			glog.Infof("azureDisk - Disk %s already formatted, will not format", disk)
-		}
-	}
-}
-
-func diskLooksUnformatted(disk string, exec mount.Exec) (bool, error) {
-	args := []string{"-nd", "-o", "FSTYPE", disk}
-	glog.V(4).Infof("Attempting to determine if disk %q is formatted using lsblk with args: (%v)", disk, args)
-	dataOut, err := exec.Run("lsblk", args...)
-	if err != nil {
-		glog.Errorf("Could not determine if disk %q is formatted (%v)", disk, err)
-		return false, err
-	}
-	output := libstrings.TrimSpace(string(dataOut))
-	return output == "", nil
-}

pkg/volume/azure_dd/azure_common_unsupported.go

@@ -26,6 +26,3 @@ func scsiHostRescan(io ioHandler, exec mount.Exec) {
 func findDiskByLun(lun int, io ioHandler, exec mount.Exec) (string, error) {
 	return "", nil
 }
-
-func formatIfNotFormatted(disk string, fstype string, exec mount.Exec) {
-}