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[209.132.180.67]) by mx.google.com with ESMTP id v14-v6si3947262pfe.149.2018.06.13.19.02.21; Wed, 13 Jun 2018 19:02:35 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935846AbeFNCB6 (ORCPT + 99 others); Wed, 13 Jun 2018 22:01:58 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:38196 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S935583AbeFNCB5 (ORCPT ); Wed, 13 Jun 2018 22:01:57 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A5A688A9FF; Thu, 14 Jun 2018 02:01:56 +0000 (UTC) Received: from ming.t460p (ovpn-12-71.pek2.redhat.com [10.72.12.71]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0573B2023487; Thu, 14 Jun 2018 02:01:42 +0000 (UTC) Date: Thu, 14 Jun 2018 10:01:38 +0800 From: Ming Lei To: Christoph Hellwig Cc: Jens Axboe , Alexander Viro , Kent Overstreet , David Sterba , Huang Ying , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o , "Darrick J . Wong" , Coly Li , Filipe Manana , Randy Dunlap Subject: Re: [PATCH V6 15/30] block: introduce bio_clone_chunk_bioset() Message-ID: <20180614020137.GF19828@ming.t460p> References: <20180609123014.8861-1-ming.lei@redhat.com> <20180609123014.8861-16-ming.lei@redhat.com> <20180613145654.GE4693@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180613145654.GE4693@infradead.org> User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Thu, 14 Jun 2018 02:01:56 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Thu, 14 Jun 2018 02:01:56 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'ming.lei@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 13, 2018 at 07:56:54AM -0700, Christoph Hellwig wrote: > On Sat, Jun 09, 2018 at 08:29:59PM +0800, Ming Lei wrote: > > There is one use case(DM) which requires to clone bio chunk by > > chunk, so introduce this API. > > I don't think DM is the special case here. The special case is the > bounce code that only wants single page bios. Between that, and the > fact that we only have two callers and one of them is inside the > block layer I would suggest to fold in the following patch to make > bio_clone_bioset clone in multi-page bvecs and make the bounce code > use the low-level interface directly: Bounce limits the max pages as 256 will do bio splitting, so won't need this change. Thanks, Ming