linux-kernel - Re: [PATCH 2/4] f2fs: do not skip writing file meta during fsync

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Date:	Wed, 27 Mar 2013 10:18:48 +0900
From:	Jaegeuk Kim <jaegeuk.kim@...sung.com>
To:	Namjae Jeon <linkinjeon@...il.com>
Cc:	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net
Subject: Re: [PATCH 2/4] f2fs: do not skip writing file meta during fsync

2013-03-27 (수), 09:57 +0900, Namjae Jeon:
> 2013/3/27, Jaegeuk Kim <jaegeuk.kim@...sung.com>:
> > 2013-03-26 (화), 09:48 +0900, Namjae Jeon:
> >> 2013/3/25, Jaegeuk Kim <jaegeuk.kim@...sung.com>:
> >> > This patch removes data_version check flow during the fsync call.
> >> > The original purpose for the use of data_version was to avoid writng
> >> > inode
> >> > pages redundantly by the fsync calls repeatedly.
> >> Hi Jaegeuk.
> >> > However, when user can modify file meta and then call fsync, we should
> >> > not
> >> > skip fsync procedure.
> >> I have a question.
> >> Which case does user can directly modify meta ? Recovery tool ?
> >
> > The meta means the inode information like atime, mtime, size, and so on,
> > which can be modified by setattr() or something other vfs apis.
> > Thanks,
> I understood. Thanks for your explanation :)
> One more,,
> When inode state is  !(inode->i_state & I_DIRTY)), We don't need to skip ?

Even though fsync writes no data and the inode is clean, we should mark
the inode to recover after power-off-recovery.
Any data and its inode can be written to the disk clearly before fsync
was called.
Thanks,

> 
> Thanks.
> >
> >>
> >> Thanks.
> >>
> >> > So, let's remove this condition check and hope that user triggers in
> >> > right
> >> > manner.
> >> >
> >> > Signed-off-by: Jaegeuk Kim <jaegeuk.kim@...sung.com>
> >> --
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> >
> > --
> > Jaegeuk Kim
> > Samsung
> >
> --
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-- 
Jaegeuk Kim
Samsung

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