From: Andreas Dilger <adilger@sun.com>
Subject: Re: xt4 - True Readonly mount [WAS - Re: [Bug 14354] Bad corruption
 with 2.6.32-rc1 and upwards]
Date: Wed, 04 Nov 2009 01:05:28 -0700
Message-ID: <9EA6C408-DC45-457F-B7FA-93F08A769E78@sun.com>
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 <20091101054542.GP18464@mit.edu>
 <87f94c370911021359x19f57427o19e6f7bfcfadae21@mail.gmail.com>
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Cc: Greg Freemyer <greg.freemyer@gmail.com>,
	Theodore Tso <tytso@mit.edu>,
	Ted Augustine <taugustine@techpathways.com>,
	Alexey Fisher <bug-track@fisher-privat.net>,
	linux-ext4@vger.kernel.org
To: Eric Sandeen <sandeen@redhat.com>
In-reply-to: <4AEF64ED.1040703@redhat.com>
Sender: linux-ext4-owner@vger.kernel.org

On 2009-11-02, at 16:02, Eric Sandeen wrote:
> Andreas Dilger wrote:
>> I thought Takashi Sato was working on allowing a filesystem freeze
>> ioctl from userspace?  This would hook into the filesystem-specific
>> freeze code so that when the ioctl() returns the on-disk filesystem
>> is fully consistent and does not even require journal replay.
>
> That's in and done; most recent xfsprogs' xfs_freeze utility will  
> even freeze non-xfs filesystems now :)  Otherwise a wrapper utility  
> around the ioctl would be trivial to write.


It probably makes sense to add a tune2fs option to freeze and unfreeze  
the
filesystem?  That would allow ext* users to have an available/documented
command even if they don't have xfsprogs installed.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.