Re: [PATCH 4/7] xfs: zap broken inode forks

[Christoph Hellwig <hch@infradead.org>]

On Mon, Dec 04, 2023 at 12:43:51PM -0800, Darrick J. Wong wrote:
> Moving things around in the directory tree might be worse, since we'd
> now have to read the parent pointer(s) from the file to remove those
> directory connections and add the new ones to lost+found.

True.

> I /think/ scouring around in a zapped data fork for a directory access
> will return EFSCORRUPTED anyway, though that might occur at a late
> enough stage in the process that the fs goes down, which isn't
> desirable.
> 
> However, once xrep_inode massages the ondisk inode into good enough
> shape that iget starts working again, I could set XFS_SICK_INO_BMBTD (and
> XFS_SICK_INO_DIR as appropriate) after zapping the data fork so that the
> directory accesses would return EFSCORRUPTED instead of scouring around
> in the zapped fork.
> 
> Once we start persisting the sick flags, the prevention will last until
> scrub or someone came along to fix the inode, instead of being a purely
> incore flag.  But, babysteps for now.  I'll fix this patch to set the
> XFS_SICK_INO_* flags after zapping things, and the predicates to pick
> them up.

Sounds good.