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From:   Daeho Jeong <daeho43@gmail.com>
Date:   Wed, 1 Jul 2020 21:12:49 +0900
Message-ID: <CACOAw_zFLgeoomdHhRmzYMtCocTugW5AVxb2wZnoRAC9+hR9Gw@mail.gmail.com>
Subject: Re: [f2fs-dev] [PATCH] f2fs: add symbolic link to kobject in sysfs
To:     Chao Yu <yuchao0@huawei.com>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>
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> On 2020/7/1 15:04, Daeho Jeong wrote:
> > Actually, I want to keep the mount number remaining to the same
> > number, even if it's re-mounted.
>
> Then once there is f2fs umounter, the order will be incorrect...

Actually, we prepared this patch for a strictly controlled system like
Android to easily access the sysfs node for a specific partition like
userdata partition using a specific number.
In this system, we don't worry about another unexpected f2fs umounter
interfering in between unmounting and mounting a partition.

When we are under the condition that we can keep track of how many
times the userdata partition has been re-mounted, we might as well use
the original partition name like "/sys/fs/f2fs/dm-9".
This is for when we couldn't do that.