dracut: 90zfs: respect zfs_force=1 on systemd systems

[nabijaczleweli]

Motivation and Context

Poetterung again! Also #11403

Description

Currently on top of (old version of) #12108

How Has This Been Tested?

Excruciatingly in #11403

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Library ABI change (libzfs, libzfs_core, libnvpair, libuutil and libzfsbootenv)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the OpenZFS code style requirements.
• I have updated the documentation accordingly.
• I have read the contributing document.
• I have added tests to cover my changes. – none apply
• I have run the ZFS Test Suite with this change applied. – likewise
• All commit messages are properly formatted and contain Signed-off-by.

[nabijaczleweli]

Rebased, g2g

[mattvperry]

I believe the addition of ${ZFS_IMPORT_OPTS} in the zfs-import-cache.service file is causing the following regression when that environment variable is empty:

Jun 11 17:23:09 carbon zpool[28085]: too many arguments
Jun 11 17:23:09 carbon zpool[28085]: usage:
Jun 11 17:23:09 carbon zpool[28085]:         import [-d dir] [-D]
Jun 11 17:23:09 carbon zpool[28085]:         import [-o mntopts] [-o property=value] ...
Jun 11 17:23:09 carbon zpool[28085]:             [-d dir | -c cachefile] [-D] [-l] [-f] [-m] [-N] [-R root] [-F [-n]] -a
Jun 11 17:23:09 carbon zpool[28085]:         import [-o mntopts] [-o property=value] ...
Jun 11 17:23:09 carbon zpool[28085]:             [-d dir | -c cachefile] [-D] [-l] [-f] [-m] [-N] [-R root] [-F [-n]]
Jun 11 17:23:09 carbon zpool[28085]:             [--rewind-to-checkpoint] <pool | id> [newpool]
Jun 11 17:23:09 carbon systemd[1]: zfs-import-cache.service: Main process exited, code=exited, status=2/INVALIDARGUMENT

I am able to workaround this by removing ${ZFS_IMPORT_OPTS} from my unit file manually

[nabijaczleweli]

Blergh, you're right. How about if you replace ${ZFS_IMPORT_OPTS} with just $ZFS_IMPORT_OPTS? I tested with the latter and mindlessly expanded to the former, but, retesting now, the former does

'import'
'-aN'
'-o'
'cachefile=none'

while the latter does

'import'
'-aN'
'-o'
'cachefile=none'
''

which is why you see it failing.

[Evernow]

This seems to have also broken zfs-import-cache for some on Fedora. Changing that alone did not help @nabijaczleweli