Re: [PATCH 0/3] Improve block device testing coverage

[Eryu Guan <eguan@redhat.com>]

On Fri, Mar 31, 2017 at 10:43:19AM +0300, Dmitry Monakhov wrote:
> Christoph Hellwig <hch@infradead.org> writes:
> 
> > On Thu, Mar 30, 2017 at 05:19:01PM +0400, Dmitry Monakhov wrote:
> >> During LSFMM we have discussed how to test lower-backend of linux IO-stack.
> >> Common opinion was that xfstests is the most obvious solution which cover
> >> most of use cases filesystem care about.
> >> 
> >> I'm working on integration T10-DIF/DIF data integrity features to ext4,
> >> for that reason we need to be shure that linux integrity framework is
> >> in working state, which is currently broken in several places.
> >> 
> >> In fact, it is relatively simple to add basic coverage tests for basic
> >> IO operations over virtual device with integrity support. All we need
> >> is to add lio target support.
> >
> > First:  Thanks for adding block layer testing!
> >
> > Second: even more so than Darrick's blockdev fallocate test this is
> > the wrong place.  If I run xfstests I want to test my file system,
> > not random block device features.  Please start a proper block device
> > testsuite instead, possibly by copy and pasting code from xfstests.
> Fair enough. I also not happy to place blkdev feature  to tests/generic
> namespace. But altearnative to fork xfstests infrastructure to dedicated
> test-framework only for blkdevice seems not very good. Because fork is
> always pain. I already maintain one internal fork of xfstests which
> tests our Vituozzo's speciffic features.
> 
> May be it would be reasonable idea to add didicated namespace
> 'tests/blockdev' in xfstests, and move all blkdev related tests here?
> IMHO this is good idea. Because filesystem relay on some basic
> features from blkdev which should be tested explicitly, because
> implicit testing is too hard to debug/investigation.

I'm not sure if xfstests is the right place for blockdev tests,
especially for the pure blockdev level features (at least Darrick's
blockdev tests are testing fallocate(2) interface).

But yeah, a new tests/blockdev dir would be good if we eventually decide
adding blockdev tests to xfstests, so they're not run by default when
people want to test filesystems.

Thanks,
Eryu