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Date:   Tue, 28 May 2019 02:23:23 +0800
From:   Yao Liu <yotta.liu@ucloud.cn>
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        nbd@other.debian.org, linux-kernel@vger.kernel.org
Subject: Re: Re: [PATCH 2/3] nbd: notify userland even if nbd has already
 disconnected
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On Fri, May 24, 2019 at 09:08:58AM -0400, Josef Bacik wrote:
> On Fri, May 24, 2019 at 05:43:55PM +0800, Yao Liu wrote:
> > Some nbd client implementations have a userland's daemon, so we should
> > inform client daemon to clean up and exit.
> > 
> > Signed-off-by: Yao Liu <yotta.liu@ucloud.cn>
> 
> Except the nbd_disconnected() check is for the case that the client told us
> specifically to disconnect, so we don't want to send the notification to
> re-connect because we've already been told we want to tear everything down.
> Nack to this as well.  Thanks,
> 
> Josef
> 

But in userland, client daemon process and process which send disconnect
command are not same process, so they are not clear to each other, so
client daemon expect driver inform it to exit.
In addition, client daemon will get nbd status with nbd_genl_status interface
after it get notified and it should not re-connect if status connected == 0