Ted Ts'o wrote: > On Sat, Aug 21, 2010 at 07:40:10PM -0500, Eric Sandeen wrote: >> I'll send an xfstest but it'd be really great if could could work >> inside the xfstests framework when devising testcases... > > If you could put together an xfstests, that would be great. I hadn't > because Mike's been trying to remind me that I really need to delegate > to others :-), and we do have someone at Google who can put the > xfstest script together. You can probably do it faster than he can, > though. Hah, I'm also supposed to delegate :D Let's see what your person can come up with, I'd really like to start seeing more people contribute to the test suite. I'm happy to answer any questions. > I didn't use xfs_io because I don't know how to use it, and because > it's not one of those things which is regularly on our production > machines that we use for testing. I probably start exploring all of > the things that can be done with it, though! Sure, I know it's kind of an oddball tool, but it's really a good swiss army knife for creating testcases like this. Probably faster than writing C. :) >> Ted, is just checking for fs corruption is enough or do you think a >> test needs the debugfs stat inspection step? It'd be easy enough >> to special-case a debugfs step for ext4. > > Well, if we end up suppressing the EOFBLOCKS_FL test e2fsck (which is > what we've already done as an emergency workaround) we can't count on > e2fsck detecting the problem, which is why I phrased this the way I > did for Aditya's benefit. Ok. Explicitly exercising blocks-past-EOF on any fallocate-capable fs is probably a good thing for the test to do, but since ext4 in particular had a bug, we can always do a debugfs step under an FSTYP==ext4 case, which is silent on success, and prints out something on failure (which would change the output and make the test fail) -Eric >>> What I normally do is run it something like this: >>> >>> mount /scratch ; pushd /scratch; ~/testcase <opts>; popd ; umount /scratch ; debugfs /dev/sdc1 -R "stat test-file" >>> >>> What to look for is whether the flags field is either 0x480000 or >>> 0x80000. The 0x400000 flag is the EOFBLOCKS_FL flag. If last extent >>> is uninitialized, then the EOFBLOCKS_FL flag should be set. >> only if that last extent is past i_size, though... > > Good point, and I guess I did have at least one test case where that > wasn't true. > > - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
