Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030233Ab2HXC0P (ORCPT ); Thu, 23 Aug 2012 22:26:15 -0400 Received: from acsinet15.oracle.com ([141.146.126.227]:25677 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932135Ab2HXC0M (ORCPT ); Thu, 23 Aug 2012 22:26:12 -0400 To: Tejun Heo Cc: Kent Overstreet , linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com, vgoyal@redhat.com, mpatocka@redhat.com, bharrosh@panasas.com, Jens Axboe , NeilBrown , Lars Ellenberg , Peter Osterlund , Sage Weil , "Martin K. Petersen" Subject: Re: [PATCH v6 11/13] block: Rework bio_pair_split() From: "Martin K. Petersen" Organization: Oracle References: <1345655050-28199-1-git-send-email-koverstreet@google.com> <1345655050-28199-12-git-send-email-koverstreet@google.com> <20120822210410.GL19212@google.com> Date: Thu, 23 Aug 2012 22:25:47 -0400 In-Reply-To: <20120822210410.GL19212@google.com> (Tejun Heo's message of "Wed, 22 Aug 2012 14:04:10 -0700") Message-ID: User-Agent: Gnus/5.130005 (Ma Gnus v0.5) Emacs/24.0.97 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1253 Lines: 26 >>>>> "Tejun" == Tejun Heo writes: Tejun> I complained about this in the last posting and in the previous Tejun> patch. Please respond. Martin, are you okay with these Tejun> integrity changes? I missed the first several iterations of all this while I was out on vacation. I'll have to try to wrap my head around the new approach. However, I'm not sure I like the overall approach of the new splitting. Instead of all this cloning, slicing and dicing of bio_vecs I'd rather we bit the bullet and had an offset + length for the vector inside each bio. That way we could keep the bio_vec immutable and make clones more lightweight since their vecs would always point to the parent. This also makes it trivial to split I/Os in the stacking drivers and removes evils in the partial completion code path. It would also allow to sever the ties between "size of block range operated on" vs. bi_size which we need for copy offload, discard, etc. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/