From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17C9AC433EF for ; Thu, 3 Feb 2022 19:34:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351574AbiBCTen (ORCPT ); Thu, 3 Feb 2022 14:34:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234820AbiBCTek (ORCPT ); Thu, 3 Feb 2022 14:34:40 -0500 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 014FDC06173D; Thu, 3 Feb 2022 11:34:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=YFLdf+yXWDyqnOqAs6w9z7uJ08NBv+2fURUugK0F1GY=; b=QQoe4UndTJBd/gJfKiwRzpeeet 4JmUN6YpnNX9DYIvdhEW4gGAmzAY4iJcrT9+yl+7RzK9VJRfM6X00mNxkFqcYaMpmB9Au9hsgWlZD ngUcGTa0+FogmMxQCXHNIL1F42PEbXs8Dq3IqSgYJKGdCSESKgpRydfKBWHGQQgemhvrjmcYCl0cx swBpj2g5oWkXqtlDRS1EyJVf3Cqs+N53XPhC8TLYUZk1qdQbnnwAN8ZRRpI3s8GI9soK4wlp0kc6Z eTKXzrjjQbuiQC+xv1PdI0pTr+z6M50XJHX3xneAkraCF4vlAV9pBIkIU8SJGKKLMQF2JJikhHnss OQit0XrQ==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nFhsB-002b1R-NQ; Thu, 03 Feb 2022 19:34:27 +0000 Date: Thu, 3 Feb 2022 11:34:27 -0800 From: Luis Chamberlain To: Christoph Hellwig , Keith Busch Cc: Adam Manzanares , Vincent Fu , Mikulas Patocka , Javier =?iso-8859-1?Q?Gonz=E1lez?= , Chaitanya Kulkarni , "linux-block@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "dm-devel@redhat.com" , "linux-nvme@lists.infradead.org" , linux-fsdevel , Jens Axboe , "msnitzer@redhat.com >> msnitzer@redhat.com" , Bart Van Assche , "martin.petersen@oracle.com >> Martin K. Petersen" , "roland@purestorage.com" , Hannes Reinecke , "kbus @imap.gmail.com>> Keith Busch" , "Frederick.Knight@netapp.com" , "zach.brown@ni.com" , "osandov@fb.com" , "lsf-pc@lists.linux-foundation.org" , "djwong@kernel.org" , "josef@toxicpanda.com" , "clm@fb.com" , "dsterba@suse.com" , "tytso@mit.edu" , "jack@suse.com" , Kanchan Joshi Subject: Re: [RFC PATCH 3/3] nvme: add the "debug" host driver Message-ID: References: <20220201102122.4okwj2gipjbvuyux@mpHalley-2> <20220202060154.GA120951@bgt-140510-bm01> <20220203160633.rdwovqoxlbr3nu5u@garbanzo> <20220203161534.GA15366@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220203161534.GA15366@lst.de> Sender: Luis Chamberlain Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Feb 03, 2022 at 05:15:34PM +0100, Christoph Hellwig wrote: > On Thu, Feb 03, 2022 at 08:06:33AM -0800, Luis Chamberlain wrote: > > On Wed, Feb 02, 2022 at 06:01:13AM +0000, Adam Manzanares wrote: > > > BTW I think having the target code be able to implement simple copy without > > > moving data over the fabric would be a great way of showing off the command. > > > > Do you mean this should be implemented instead as a fabrics backend > > instead because fabrics already instantiates and creates a virtual > > nvme device? And so this would mean less code? > > It would be a lot less code. In fact I don't think we need any new code > at all. Just using nvme-loop on top of null_blk or brd should be all > that is needed. Mikulas, That begs the question why add this instead of using null_blk with nvme-loop? Luis