[systemd-devel] Block device shutdown "hook"

[Ian Pilcher]

Does systemd provide any sort of "hook" mechanism to call a script
program when a block device is unmounted (or otherwise no longer being
used) on shutdown?

I'm toying with the idea of creating an alternative way of managing
dm-cache devices -- something that will operate a bit more like bcache,
rather than LVM cache.  It seems to be pretty straightforward, except
for the need to properly shutdown the dm-cache once any filesystems,
VGs, etc., on it are no longer in use.

Is there a way to tell systemd how to "shut down" a block device?

Thanks!
-- 
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Ian Pilcher                                         arequipeno at gmail.com
-------- "I grew up before Mark Zuckerberg invented friendship" --------
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