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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 1431BC10F00 for ; Thu, 21 Mar 2019 15:54:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E3FAA218A5 for ; Thu, 21 Mar 2019 15:54:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728353AbfCUPyg (ORCPT ); Thu, 21 Mar 2019 11:54:36 -0400 Received: from mx2.suse.de ([195.135.220.15]:36062 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727823AbfCUPyf (ORCPT ); Thu, 21 Mar 2019 11:54:35 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 6830FAB6D; Thu, 21 Mar 2019 15:54:34 +0000 (UTC) Subject: Re: [PATCH 1/2] block: bio: ensure newly added bio flags don't override BVEC_POOL_IDX To: Jens Axboe , Johannes Thumshirn Cc: Bart Van Assche , Christoph Hellwig , Jan Kara , Linux Block Layer Mailinglist , Linux FSDEVEL Mailinglist References: <20190321123045.32396-1-jthumshirn@suse.de> <20190321123045.32396-2-jthumshirn@suse.de> <78cf685f-2bb4-c494-4677-afa513b47339@fb.com> <17f1ef65-5fcf-0cba-4d37-a43d5e5038b0@kernel.dk> <64dce739-128b-1770-4062-9ba566ceda63@suse.de> From: Hannes Reinecke Message-ID: <40029cb8-f5bd-51e4-2019-797f443e3c03@suse.de> Date: Thu, 21 Mar 2019 16:54:33 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 3/21/19 3:25 PM, Jens Axboe wrote: > On 3/21/19 8:23 AM, Johannes Thumshirn wrote: >> On 21/03/2019 15:21, Jens Axboe wrote: >>> On 3/21/19 8:15 AM, Jens Axboe wrote: >>>> You also haven't solved the issue of now having an extra bit, 2/2 uses >>>> the last bit which the other patch already took... >>> >>> Here's one way - kill BIO_SEG_VALID. We should just use >>> ->bi_phys_segments to tell if it's valid or not. This patch uses -1 to >>> signify it's not. >>> >>> Totally untested... >> >> >> That sounds like an idea, I'll trow some testing at it and report back. > > That'd be great, thanks. If we can do that as a prep patch for you, then > you can just use an enum and not worry about initializing since I'll just > shove BIO_PAGE_NO_REF at the end. > > And this is simpler than having to shift the masks around. > And it would also remove the possiblity that SEG_VALID and nr_phys_segments get out of sync. We still have some unresolved issues revolving around this problem... So yeah, I do like it, too. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 21284 (AG Nürnberg)