From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Sat, 3 Oct 2015 23:32:35 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Cc: viro@ZenIV.linux.org.uk, jack@suse.cz, dedekind1@gmail.com,
 richard.weinberger@gmail.com, linux-mtd@lists.infradead.org,
 linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v3 05/39] fs: super: introduce a get_super_cdev to get
 super by a cdev reference
Message-ID: <20151004063235.GG28519@infradead.org>
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As mentioned before I don't think the cdev has any business in core VFS
code.  You must alredy have an anonymous block device for the st_dev
value, please use that.