Re: [PATCH v2] xfs: test xfs_info on block device and mountpoint

[Zorro Lang <zlang@redhat.com>]

On Tue, Jun 25, 2019 at 07:36:16AM -0700, Darrick J. Wong wrote:
> On Tue, Jun 25, 2019 at 03:16:39PM +0800, Zorro Lang wrote:
> > On Tue, Jun 25, 2019 at 10:45:46AM +0800, Eryu Guan wrote:
> > > On Mon, Jun 24, 2019 at 09:21:03AM +0800, Zorro Lang wrote:
> > > > On Sun, Jun 23, 2019 at 02:49:19PM -0700, Darrick J. Wong wrote:
> > > > > On Sat, Jun 22, 2019 at 11:38:27PM +0800, Zorro Lang wrote:
> > > > > > There was a bug, xfs_info fails on a mounted block device:
> > > > > > 
> > > > > >   # xfs_info /dev/mapper/testdev
> > > > > >   xfs_info: /dev/mapper/testdev contains a mounted filesystem
> > > > > > 
> > > > > >   fatal error -- couldn't initialize XFS library
> > > > > > 
> > > > > > xfsprogs has fixed it by:
> > > > > > 
> > > > > >   bbb43745 xfs_info: use findmnt to handle mounted block devices
> > > > > > 
> > > > > > Signed-off-by: Zorro Lang <zlang@redhat.com>
> > > > > 
> > > > > Aha!  I remembered something -- xfs/449 already checks for consistency
> > > > > in the various xfs geometry reports that each command provides, so why
> > > > > not just add the $XFS_INFO_PROG $SCRATCH_DEV case at the end?
> > 
> > Hmm... But I hope the case can keep running xfs_info test even there're not
> > xfs_spaceman -c "info" or xfs_db -c "info", just skip these two steps. Due
> > to RHEL-7 has old xfsprogs, we'd like to cover bug on RHEL-7.
> > 
> > What do you think?
> 
> If there isn't an xfs_db -c info command then xfs_info <blockev> won't
> work because that's what it does internally.
> 
> Sooo unless you're backporting the new xfs_db info command to rhel7
> xfsprogs as well as the new xfs_info wrapper, the test ought to just
> _notrun on rhel7.

No, I'm not trying to test an unmount <blockdev>. I'm trying to run
xfs_info on a mounted <blockdev>.

There was a bug. RHEL-7 xfsprogs can get a mounted device info:

# xfs_growfs -p xfs_info -n /dev/mapper/home 
meta-data=/dev/mapper/home isize=512    agcount=4, agsize=47341056 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=189364224, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=92463, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0


But RHEL-8.0 xfsprogs can't do that:

# xfs_info /dev/mapper/xfshome
xfs_info: /dev/mapper/xfshome contains a mounted filesystem

fatal error -- couldn't initialize XFS library

Thanks,
Zorro

> 
> --D
> 
> > > > 
> > > > Wow, there're so many cases, can't sure what we've covered now:)
> > > > 
> > > > Sure, I can do this change on xfs/449, if Eryu thinks it's fine to increase
> > > > the test coverage of a known case.
> > > 
> > > Given that we're having more and more tests and the test time grows
> > > quickly, I'm fine now with adding such small & similar test to existing
> > > test case to reuse the test setups, especially when XFS maintainer
> > > agrees to do so :)
> > > 
> > > Thanks,
> > > Eryu