Re: [PATCH 26/31] xfs: add parent pointer ioctls

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

> +	if (memcmp(&handle->ha_fsid, mp->m_fixedfsid, sizeof(struct xfs_fsid)))
> +		return -ESTALE;
> +
> +	if (handle->ha_fid.fid_len != xfs_filehandle_fid_len())
> +		return -EINVAL;

Maybe we should just stash the fid without the fsid?  The check for a
match fsid when userspace already had to resolve it to even call the
ioctl is a bit silly.