From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756641Ab2IUAfa (ORCPT ); Thu, 20 Sep 2012 20:35:30 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:60470 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755058Ab2IUAf2 (ORCPT ); Thu, 20 Sep 2012 20:35:28 -0400 Date: Thu, 20 Sep 2012 17:35:23 -0700 From: Tejun Heo To: Kent Overstreet Cc: linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com, axboe@kernel.dk, neilb@suse.de Subject: Re: [PATCH v2 20/26] block: Add bio_for_each_segment_all() Message-ID: <20120921003523.GX7264@google.com> References: <1347322957-25260-1-git-send-email-koverstreet@google.com> <1347322957-25260-21-git-send-email-koverstreet@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1347322957-25260-21-git-send-email-koverstreet@google.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, Sep 10, 2012 at 05:22:31PM -0700, Kent Overstreet wrote: > This is part of the immutable bvec prep work; bio_for_each_segment() is > going to have a different implementation so these need to be split > apart. > > This change is also to better document the intent of code that's using > it - bio_for_each_segment_all() is only legal to use for code that owns > the bio. How about something like following? __bio_for_each_segment() iterates bvecs from the specified index instead of bio->bv_idx. Currently, the only usage is to walk all the bvecs after the bio has been advanced by specifying 0 index. To help immutable bvec implementation, replace it with bio_for_each_segment_all() which also better documents the intent of code that's using it. Note that bio_for_each_segment_all() should only be used by the code which owns the bio. -- tejun