From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Subject: Re: [PATCHSET v3.1 0/7] data integrity: Stabilize pages during writeback for various fses
Date: Wed, 11 May 2011 01:29:28 +0900
Message-ID: <87r586plhz.fsf@devron.myhome.or.jp>
References: <20110509230318.19566.66202.stgit@elm3c44.beaverton.ibm.com>
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	<20110510133603.GA5823@infradead.org>
	<874o524q9h.fsf@devron.myhome.or.jp>
	<20110510144939.GI4402@quack.suse.cz>
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	<20110510161836.GL4402@quack.suse.cz>
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Cc: Christoph Hellwig <hch@infradead.org>,
	"Darrick J. Wong" <djwong@us.ibm.com>,
	Theodore Tso <tytso@mit.edu>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Jens Axboe <axboe@kernel.dk>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	Jeff Layton <jlayton@redhat.com>,
	Dave Chinner <david@fromorbit.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	Dave Hansen <dave@linux.vnet.ibm.com>, linux-mm@kvack.org,
	Chris Mason <chris.mason@oracle.com>,
	Joel Becker <jlbec@evilplan.org>,
	linux-scsi <linux-scsi@vger.kernel.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-ext4@vger.kernel.org, Mingming Cao <mcao@us.ibm.com>
To: Jan Kara <jack@suse.cz>
In-Reply-To: <20110510161836.GL4402@quack.suse.cz> (Jan Kara's message of
	"Tue, 10 May 2011 18:18:36 +0200")
Sender: linux-ext4-owner@vger.kernel.org

Jan Kara <jack@suse.cz> writes:

> On Wed 11-05-11 00:24:58, OGAWA Hirofumi wrote:
>> Jan Kara <jack@suse.cz> writes:
>> 
>> >> Isn't it reallocated blocks too, and metadata too?
>> >   Reallocated blocks - not really. For a block to be freed it cannot be
>> > under writeback and when it's freed no writeback is started.
>> 
>> Sure for data -> data reallocated case. metadata -> data/metadata is
>> still there.
>   Unless you properly use bforget() (which you should I think). But I have
> not really checked this in detail for a while.

bforget() doesn't wait IO, right?
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>