Re: [PATCH v2 1/2] shared: move btrfs clone device testcase to the shared group

[Christoph Hellwig <hch@infradead.org>]

On Tue, Mar 19, 2024 at 12:16:33PM +0800, Zorro Lang wrote:
> I didn't suggest to make it a shared case directly, I asked if there's a
> _require_xxxx helper to make this case notrun on "not proper" fs, not
> just use "btrfs ext4" to be whitelist :
> 
> https://lore.kernel.org/fstests/20240312044629.hpaqdkl24nxaa3dv@dell-per750-06-vm-08.rhts.eng.pek2.redhat.com/
> 
> In my personal opinion, the "shared" directory is a place to store the cases
> which are nearly to be generic, but not ready. It's a place to remind us
> there're still some cases use something likes "supported btrfs ext4" as the
> hard condition of _notrun, rather than a flexible _require_xxx helper. These
> cases in shared better to be moved to generic, if we can improve it in one day.
> 
> It more likes a "TODO" list of generic. If we just write it in generic/
> directory, I'm afraid we'll leave it in hundreds of generic cases then forget it.
> 
> What do you think?

I like we're you're going, but I'd like to take it a step further:

I think we should just kill _supported_fs entirely.

tests/$FSTYPE is run for $FSTYP only, period.
tests/generic/ is run for all file systems, and run/notrun deciѕions
should be based on feature checks.  Where they can't happen without
fs-sepcific infrastructure we need a _require/_have check that
switches on $FSTYP like we already have in many places.  shared
should be folded into generic.

And a list of all hte places where we have to or should plug fs
knowledge in would be really nice as well..