From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-block-owner@vger.kernel.org>
Received: from bombadil.infradead.org ([65.50.211.133]:49971 "EHLO
        bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1751630AbdHaKX0 (ORCPT
        <rfc822;linux-block@vger.kernel.org>);
        Thu, 31 Aug 2017 06:23:26 -0400
Date: Thu, 31 Aug 2017 03:23:24 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>,
        linux-block@vger.kernel.org, Ulf Hansson <ulf.hansson@linaro.org>,
        linux-mmc <linux-mmc@vger.kernel.org>,
        Bough Chen <haibo.chen@nxp.com>,
        Alex Lemberg <alex.lemberg@sandisk.com>,
        Mateusz Nowak <mateusz.nowak@intel.com>,
        Yuliy Izrailov <Yuliy.Izrailov@sandisk.com>,
        Jaehoon Chung <jh80.chung@samsung.com>,
        Dong Aisheng <dongas86@gmail.com>,
        Das Asutosh <asutoshd@codeaurora.org>,
        Zhangfei Gao <zhangfei.gao@gmail.com>,
        Sahitya Tummala <stummala@codeaurora.org>,
        Harjani Ritesh <riteshh@codeaurora.org>,
        Venu Byravarasu <vbyravarasu@nvidia.com>,
        Shawn Lin <shawn.lin@rock-chips.com>
Subject: Re: [PATCH V5 11/13] mmc: block: Add CQE support
Message-ID: <20170831102324.GA6757@infradead.org>
References: <1502366898-23691-1-git-send-email-adrian.hunter@intel.com>
 <1502366898-23691-12-git-send-email-adrian.hunter@intel.com>
 <CACRpkdZ2=D2tLD0L0M1T_z0_5gMhiPKqUHuOcMgdA72PHLHG8A@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
In-Reply-To: <CACRpkdZ2=D2tLD0L0M1T_z0_5gMhiPKqUHuOcMgdA72PHLHG8A@mail.gmail.com>
Sender: linux-block-owner@vger.kernel.org
List-Id: linux-block@vger.kernel.org

On Sun, Aug 20, 2017 at 02:13:03PM +0200, Linus Walleij wrote:
> So adding a new (in effect) invasive block driver needs to at least
> be CC:ed to the block maintainers so we don't sneak anything like
> that in under the radar.

Yes.

> And this semaphoring and threading is just as confusing as ever and now
> we have two of them. (Sorry, I'm grumpy.)

But your are grumpy for a good reason.  The MMC driver is a pain
to understand for even a seasons block layer developer.

> What we need is an MMC stack where it is clear where blocks come in
> and out and how they are processed by the block layer, but now we
> already have a scary Rube Goldberg-machine and it is not getting better.
> If people have different feelings they can tell me off right now.

Agreed.

> 
> I have my hopes up that we can get the code lesser and more readable
> with MQ, as I tried to illustrate in my attempts, which are indeed lame
> because they don't work because of misc and SDIO use cases, but
> I'm honestly doing my best. Currently with other clean-ups to get a
> clean surface to do that.
> 
> As it stands, the MQ migration work size is in some spots doubled or
> more than doubled after this commit :(

I don't think we should merge this.