[PATCH] xfs: in _attrlist_by_handle, copy the cursor back to userspace

[Dave Chinner]

On Tue, Aug 02, 2016 at 08:40:35AM -0700, Darrick J. Wong wrote:
> On Tue, Aug 02, 2016 at 05:25:17AM -0700, Christoph Hellwig wrote:
> > On Mon, Aug 01, 2016 at 08:56:51PM -0700, Darrick J. Wong wrote:
> > > When we're iterating inode xattrs by handle, we have to copy the
> > > cursor back to userspace so that a subsequent invocation actually
> > > retrieves subsequent contents.
> > 
> > Testcase?
> 
> Found it while continuing development of xfs_scrub.  I'll send along the
> xfstest patch when I've finished polishing it.  (It was harder than usual since
> xfs_io doesn't /use/ the attr-by-handle interface... nothing does.)

It was (and probably still is) used by SGI's HSM. I thought there
was some coverage of the interface in the dmapi part of the xfstests
suite, but perhaps it's only tested by SGI's internal hsm test
suite...

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com