From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F537216605; Thu, 16 Oct 2025 04:57:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760590682; cv=none; b=aWsB1st6SiqnqV/+P7LhQ0wZPtXyWVj/UGcTZvCCOP15ngFuX34mKQqJI2JA9G/0R0Kz+3QPzcSNZBq0LUftDA04RbVvo0hqDqKdj0N+Qax49jKnnvqo6T5XOobfsMg3pdWjvoVYpw0JW4Ch25fnZrR7tUatGxEk2RIftamYGV4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760590682; c=relaxed/simple; bh=ECCnn3TI8/y8/y8DCci41y7eCrVjsNbpjUUR2M/wb1c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aJIuzobg+knn0kw+7EYS0Lr5vDZEfrXqkH1t4+94MMyYV6qLiVoDN1vnVXbogJ2fSZuQevIx+tCGoyOvyyazu5Sd855kljrlin7LEImGYb89sSZYqq/9PBrUqvWwJpnBRz9H7xOKjhYAVJqgilurcVcHF2xjMdxMWXFhJWBf0vQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=kX+ecOXG; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="kX+ecOXG" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=83RRaMW02lAZZkMy97sWQR+uVw4y0FfJh7nVF0t04Bk=; b=kX+ecOXGUo23ibqL6z9XtV+dMr FZAO8B5A2cssmhP13D4IOuXU+ZdP2yDszBs4KHZxyMs1JnTIVjRhOw2WuxmGu6OfRh759Kye69cr0 PlO8Wo38DXVb3L0Na3KqkMGBt4SPshYCeoql4xQiYQ3wY7gzC0oUZJUoRii/XwmIzMu1/RyKZKqHV Ktkj0d89CONRXmDjdBXeNCkD9KxgMbGmpjjrgm0u5tixryiv4NPLgIn5jR5D0sYROhptcCWbl6Yc3 HOfblqXCWwbqPTx5pd9PUiQVoA5reALlusiMcPs+xiIUuFtNqsqe18iBlPQrwgtwqbGhdqjclQ9HR v+YieS/Q==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1v9G3o-00000003SW2-2m3r; Thu, 16 Oct 2025 04:57:56 +0000 Date: Wed, 15 Oct 2025 21:57:56 -0700 From: Christoph Hellwig To: Amir Goldstein Cc: =?iso-8859-1?Q?Andr=E9?= Almeida , linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, kernel-dev@igalia.com, Miklos Szeredi , Chris Mason , David Sterba , Anand Jain , "Guilherme G . Piccoli" Subject: Re: [RFC PATCH 0/1] ovl: brtfs' temp_fsid doesn't work with ovl index=on Message-ID: References: <20251014015707.129013-1-andrealmeid@igalia.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Oct 15, 2025 at 01:09:26PM +0200, Amir Goldstein wrote: > FWIW this operation already exists in export_operations. > It is currently only used by pnfs and only implemented by xfs. > I would nor object for overlayfs to use this method if implemented > and fall back to copying uuid directly from s_uuid The get_uuid export operation is specifically about an on-disk superblock that the pnfs client can match. Overloading it for in-core information would be very confusing and also problematic if it doesn't exist on-disk in this format. In retrospective it should be called get_disk_uuid or something similar.