Re: [PATCH 4.19 070/243] xfs: extent shifting doesnt fully invalidate page cache

Greg Kroah-Hartman
2019-12-12T09:37:37Z

On Thu, Dec 12, 2019 at 08:26:13AM +0900, Nobuhiro Iwamatsu wrote:
> On Wed, Dec 11, 2019 at 04:03:52PM +0100, Greg Kroah-Hartman wrote:
> > From: Dave Chinner <dchinner@redhat.com>
> >
> > [ Upstream commit 7f9f71be84bcab368e58020a42f6d0dd97adf0ce ]
> >
> > The extent shifting code uses a flush and invalidate mechainsm prior
> > to shifting extents around. This is similar to what
> > xfs_free_file_space() does, but it doesn't take into account things
> > like page cache vs block size differences, and it will fail if there
> > is a page that it currently busy.
> >
> > xfs_flush_unmap_range() handles all of these cases, so just convert
> > xfs_prepare_shift() to us that mechanism rather than having it's own
> > special sauce.
> >
> > Signed-off-by: Dave Chinner <dchinner@redhat.com>
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > Signed-off-by: Sasha Levin <sashal@kernel.org>
>
>
> This commit also required following commit:
>
> commit 1749d1ea89bdf3181328b7d846e609d5a0e53e50
> Author: Brian Foster <bfoster@redhat.com>
> Date: Fri Apr 26 07:30:24 2019 -0700
>
> xfs: add missing error check in xfs_prepare_shift()
>
> xfs_prepare_shift() fails to check the error return from
> xfs_flush_unmap_range(). If the latter fails, that could lead to an
> insert/collapse range operation over a delalloc range, which is not
> supported.
>
> Add an error check and return appropriately. This is reproduced
> rarely by generic/475.
>
> Fixes: 7f9f71be84bc ("xfs: extent shifting doesn't fully invalidate page cache")
> Signed-off-by: Brian Foster <bfoster@redhat.com>
> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> Reviewed-by: Allison Collins <allison.henderson@oracle.com>
> Reviewed-by: Dave Chinner <dchinner@redhat.com>

Now added, thanks!

greg k-h