From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 2 Apr 2015 10:41:34 -0400 (EDT) From: Jan Tulak Message-ID: <35967469.6829911.1427985694256.JavaMail.zimbra@redhat.com> In-Reply-To: <550C6DAD.4060602@sandeen.net> References: <550C46B2.8060407@sandeen.net> <550C4951.1030804@sandeen.net> <550C6DAD.4060602@sandeen.net> Subject: Re: [PATCH 2/2] fstests: Add overlayfs support MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit To: Eric Sandeen Cc: fstests@vger.kernel.org List-ID: ----- Original Message ----- > From: "Eric Sandeen" > To: fstests@vger.kernel.org > Sent: Friday, 20 March, 2015 7:57:49 PM > Subject: Re: [PATCH 2/2] fstests: Add overlayfs support > > On 3/20/15 11:22 AM, Eric Sandeen wrote: > > If OVERLAYFS=1 is set, then every time we mount the scratch or > > test device, set up overlayfs directories under it, and switch > > the directory under test to the upper directory. > > > > This doesn't specifically or directly test overlayfs, it simply > > runs the existing tests over it. As such, a few tests fail, > > and may be expected to fail due to overlayfs limitations and > > caveats. I haven't sorted through the results yet. > > > > Signed-off-by: Eric Sandeen > > Zach has almost convinced me that this is the wrong approach and/or > not worth doing, or at least not merging. > > Many of the failures are as a result of this being tacked on, and > several tests wouldn't be expected to work at all. > > So I dunno. What do people think; it's at least interesting on the > side, to see what falls off. > > Good news is, no oopses yet! :) > Well, I agree with Zach. It would be good to have overlayfs, but I think it should be a standalone FS. Overlayfs has some specific things, though. As it needs more directories for work, we can suppose lowerdir is going to be TEST_DIR/SCRATCH_DIR, but what about upperdir? And o we need to be able to explicitly set what filesystem they should be on? Your patch put it all into a single directory, but I think we should be able to test it on different devices. So I would say we need have both, something like _require_test_overlay # basically what your patch do, a single step to make $TEST_DIR in overlay and OVERLAY_UPPER_FS="tmpfs" OVERLAY_LOWER_FS="xfs" _require_scratch_overlay I think we should be able to manipulate with underlying directories directly - though this can be the case only for some specific tests that will do all the work around overlayfs manually. I don't feel to answer this question myself. I'm afraid I'm bringing more question than answers, though. :-) -- Jan Tulak jtulak@redhat.com