From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH] block new writers on frozen filesystems
Date: Sun, 13 Feb 2005 16:24:21 +0100
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Cc: Christoph Hellwig <hch@lst.de>, Andrew Morton <akpm@osdl.org>,
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To: Anton Altaparmakov <aia21@cam.ac.uk>
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On Sun, Feb 13, 2005 at 03:05:22PM +0000, Anton Altaparmakov wrote:
> > This should block new data writers.  New metadata writes need to be
> > blocked in the individual filesystem, and only when the state is set
> > to SB_FREEZE_TRANS (a few steps later in freeze_bdev).
> 
> Why this distinction?  At least on NTFS metadata is stored in normal files 
> (everything is a file in NTFS) and the same readpage/writepage address 
> space operations are used to access both...

Because flushing the data after you block new writes usually involved
writing out metadata aswell, so you can't block them at the same time
without deadlocking.