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 X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69652C18E5B for ; Tue, 10 Mar 2020 16:42:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 36A59222C3 for ; Tue, 10 Mar 2020 16:42:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="r/icAaHd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726497AbgCJQmc (ORCPT ); Tue, 10 Mar 2020 12:42:32 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:53386 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726395AbgCJQmc (ORCPT ); Tue, 10 Mar 2020 12:42:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; 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=OD+nprfZaFcbxeG2a36sbeRwNh3eux46qu3CwbbPO8U=; b=r/icAaHdh7hJTNlYV4K6ua85UV zKOM+Hg/UnCozR3fliYS+ntqvzcA72vxzsYG1kRT9eIdtpVMqvZrCeZAW7sRsOOagdJhe8beI95S9 voGuiWK3X8nDO9xvmL5hcsE/LG2WaLT9/aqHP17BK32nqU4uXbAMX1yW1kHaqR3PclFjRyKCB/fzo 99xcCk477K0YNml20BgXo38WTe1tsJ6Cs06j0AMPnXeSucf9Su/UA4GTXZ+TPiYRBrPtI/36lQ0b7 pjnZj/swKU+2gc/ivOHkSfBmnGfvSUGNO6QzGxHPWtPu/8x5FZ4Tn4Xzwec1227b33A2W49Bv473y JTBALVIQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jBhxd-0004Em-KL; Tue, 10 Mar 2020 16:42:29 +0000 Date: Tue, 10 Mar 2020 09:42:29 -0700 From: Christoph Hellwig To: Johannes Thumshirn Cc: Jens Axboe , Christoph Hellwig , linux-block , Damien Le Moal , Keith Busch , "linux-scsi @ vger . kernel . org" , "Martin K . Petersen" Subject: Re: [PATCH 00/11] Introduce Zone Append for writing to zoned block devices Message-ID: <20200310164229.GA15878@infradead.org> References: <20200310094653.33257-1-johannes.thumshirn@wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200310094653.33257-1-johannes.thumshirn@wdc.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Mar 10, 2020 at 06:46:42PM +0900, Johannes Thumshirn wrote: > For null_blk the emulation is way simpler, as null_blk's zoned block > device emulation support already caches the write pointer position, so we > only need to report the position back to the upper layers. Additional > caching is not needed here. > > Testing has been conducted by translating RWF_APPEND DIOs into > REQ_OP_ZONE_APPEND commands in the block device's direct I/O function and > injecting errors by bypassing the block layer interface and directly > writing to the disc via the SCSI generic interface. We really need a user of this to be useful upstream. Didn't you plan to look into converting zonefs/iomap to use it? Without that it is at best a RFC. Even better would be converting zonefs and the f2fs zoned code so that can get rid of the old per-zone serialization in the I/O scheduler entirely.