Re: [PATCH 1/2] xfs_repair: validate alignment of inherited rt extent hints

[Christoph Hellwig <hch@infradead.org>]

On Fri, Jul 02, 2021 at 07:57:50PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> If we encounter a directory that has been configured to pass on an
> extent size hint to a new realtime file and the hint isn't an integer
> multiple of the rt extent size, we should turn off the hint because that
> is a misconfiguration.
> 
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---
>  repair/dinode.c |   28 +++++++++++++++++++++++++++-
>  1 file changed, 27 insertions(+), 1 deletion(-)
> 
> 
> diff --git a/repair/dinode.c b/repair/dinode.c
> index 291c5807..1275c90b 100644
> --- a/repair/dinode.c
> +++ b/repair/dinode.c
> @@ -2178,6 +2178,31 @@ _("Bad %s nsec %u on inode %" PRIu64 ", "), name, be32_to_cpu(t->t_nsec), lino);
>  		*dirty = 1;
>  	}
>  }
> +/*
> + * Inode verifiers on older kernels don't check that the extent size hint is an
> + * integer multiple of the rt extent size on a directory with both rtinherit
> + * and extszinherit flags set.  If we encounter a directory that is
> + * misconfigured in this way, or a regular file that inherited a bad hint from
> + * a directory, clear the hint.
> + */
> +static bool
> +zap_bad_rt_extsize_hint(

The name suggests this function does the zapping itself, while it
actually leaves that to the caller.

Oterwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>