1) Fix FakeMounter.IsLikelyNotMountPoint to return ErrNotExist if the
directory does not exist. Mounter.IsLikelyNotMountPoint interface
requires this, and RBD plugin depends on it.
lsblk reports FSTYPE of devices with partition tables as empty string "",
which is indistinguishable from empty devices. We must look for dependent
devices (i.e. partitions) to see that the device is really empty and report
error otherwise.
I checked that LVM, LUKS and MD RAID have their own FSTYPE in lsblk output,
so it should be only a partition table that has empty FSTYPE.
The main point of this patch is to run lsblk without "-n", i.e. print all
dependent devices and check if they're there.
The `file` command used here to check whether a device is formatted is not
available for CoreOS. The effect is that the mounter tries to mount an
unformatted volume which fails. This makes it quite tedious to use persistent
volumes in CoreOS.
This patch replaces the `file` command with `lsblk` which is available in
CoreOS. I checked that it's also available on RHEL, Debian, Ubuntu and SLES.
The GCE PD plugin uses safe_format_and_mount found on standard GCE images:
https://github.com/GoogleCloudPlatform/compute-image-packages/blob/master/google-startup-scripts/usr/share/google/safe_format_and_mount
On custom images where this is not available pods fail to format and
mount GCE PDs. This patch uses linux utilities in a similar way to the
safe_format_and_mount script to format and mount the GCE PD and AWS EBC
devices. That is first attempt a mount. If mount fails try to use file to
investigate the device. If 'file' fails to get any information about
the device and simply returns "data" then assume the device is not
formatted and format it and attempt to mount it again.
Signed-off-by: Sami Wagiaalla <swagiaal@redhat.com>
Yecheng Fu