From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 2/5] block: add function to issue compare and write Date: Sat, 18 Oct 2014 08:16:39 -0700 Message-ID: <20141018151639.GF30355@infradead.org> References: <1413437835-13778-1-git-send-email-michaelc@cs.wisc.edu> <1413437835-13778-3-git-send-email-michaelc@cs.wisc.edu> <20141017095555.GA360@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from bombadil.infradead.org ([198.137.202.9]:56534 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751042AbaJRPQn (ORCPT ); Sat, 18 Oct 2014 11:16:43 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Martin K. Petersen" Cc: michaelc@cs.wisc.edu, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, ceph-devel@vger.kernel.org, axboe@kernel.dk, linux-kernel@vger.kernel.org On Fri, Oct 17, 2014 at 07:38:37PM -0400, Martin K. Petersen wrote: > The problem with this is that, as it stands, a bio has no type. And it > would suck if we couldn't keep bio rw and request flags in sync. > > I wonder if it would make more sense to move the remaining rq types to > cmd_flags after I'm done with the 64-bit conversion? I'd prefer adding a cmd_type to the bio as well and avoid the 64-bit flag conversion. While we'll probably grow more types of I/Os (e.g. copy offload) I hope we can actually reduce the number of real flags, and it's easier to read for sure if we can switch on the command type in the driver.