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;
Date:   Thu, 29 Aug 2019 16:24:09 +0800
From:   Gao Xiang <gaoxiang25@huawei.com>
To:     Christoph Hellwig <hch@infradead.org>
CC:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        <devel@driverdev.osuosl.org>, <linux-fsdevel@vger.kernel.org>,
        Sasha Levin <alexander.levin@microsoft.com>,
        Valdis =?gbk?Q?Kl=A8=A5tnieks?= <valdis.kletnieks@vt.edu>,
        <linux-kernel@vger.kernel.org>, <yuchao0@huawei.com>,
        <miaoxie@huawei.com>, "Theodore Y. Ts'o" <tytso@mit.edu>,
        Eric Biggers <ebiggers@kernel.org>,
        Zefan Li <lizefan@huawei.com>
Subject: Re: [PATCH] staging: exfat: add exfat filesystem code to staging
Message-ID: <20190829082409.GA83154@architecture4>
References: <20190828160817.6250-1-gregkh@linuxfoundation.org>
 <20190828170022.GA7873@kroah.com>
 <20190829062340.GB3047@infradead.org>
 <20190829070149.GA155353@architecture4>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <20190829070149.GA155353@architecture4>
User-Agent: Mutt/1.9.4 (2018-02-28)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Christoph,

On Thu, Aug 29, 2019 at 03:01:49PM +0800, Gao Xiang wrote:
> Hi Christoph,
> 
> On Wed, Aug 28, 2019 at 11:23:40PM -0700, Christoph Hellwig wrote:
> > Can we please just review the damn thing and get it into the proper
> > tree?  That whole concept of staging file systems just has been one
> > fricking disaster, including Greg just moving not fully reviewed ones
> > over like erofs just because he feels like it.  I'm getting sick and
> > tired of this scheme.
> 
> I just want to a word on EROFS stuff (I'm not suitable to comment
> on the current exfat implementation). Since EROFS stuff has been
> in staging tree for more than a year, anyone who wants to review
> it can review this filesystem at any time.
> 
> EROFS is not just a homebrew or experimental fs for now, it has been
> widely used for many commerical smartphones, and we will upstream it
> to AOSP for more Android smartphones after it gets merged to upstream.
> I personally cc-ed you for a month, and I didn't get any objection
> from others (including Linus) for about 2 months. That isn't because
> of someone likes it, rather we cannot make no progress compared with
> some exist fs community because this is our love work.
> 
> And it's self-contained driver at least, and it's disabled by default,
> It cannot be stayed in staging tree to do a lot of EROFS feature
> improvements itself forever (since it is cleaned enough).
> It has proven its validity as well.

It seems I misunderstood your idea, sorry about that... EROFS
properly uses vfs interfaces (e.g. we also considered RCU symlink
lookup path at the very beginning of our design as Al said [1],
except for mount interface as Al mentioned [2] (thanks him for
taking some time on it), it was used for our debugging use),
and it didn't cause any extra burden to vfs or other subsystems.

[1] https://lore.kernel.org/r/20190325045744.GK2217@ZenIV.linux.org.uk/
[2] https://lore.kernel.org/r/20190720224955.GD17978@ZenIV.linux.org.uk/

Thanks,
Gao Xiang

> 
> Thanks,
> Gao Xiang
>