From: Girish Shilamkar <girish@clusterfs.com>
Subject: Re: [Patch 0/2] Journal Checksums
Date: Wed, 30 May 2007 16:06:40 +0530
Message-ID: <1180521400.13497.1.camel@alpha.linsyssoft.com>
References: <1180520892.3787.43.camel@alpha.linsyssoft.com>
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Cc: Andreas Dilger <adilger@clusterfs.com>
To: linux-ext4@vger.kernel.org
In-Reply-To: <1180520892.3787.43.camel@alpha.linsyssoft.com>
Sender: linux-ext4-owner@vger.kernel.org

Hi,
	I forgot mention, this patch is spinoff of patch originally written by
Vijayan Prabhakaran.

Thanks & Regards.
Girish

On Wed, 2007-05-30 at 16:01 +0530, Girish Shilamkar wrote:
> Hi,
>  	The following patch set adds journal checksumming support for linux
> kernel and e2fsprogs. 
> 
> Two new flags have been added i.e 
> JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT and JBD2_FEATURE_COMPAT_CHECKSUM.
> 
> _CHECKSUM flag indicates that the commit block contains the checksum for
> the blocks described the the descriptor blocks.
> Due to checksums, writing of the commit record no longer needs to be
> synchronous, this behavior is controlled using _ASYNC_COMMIT flag. Older
> kernels/e2fsck should not be able to recover the journal with
> _ASYNC_COMMIT hence it is made incompat. 
> The commit header has been extended to hold the checksum along with the
> type of the checksum.
> 
> For recovery in pass scan checksums are verified to ensure the sanity
> and completeness(in case of _ASYNC_COMMIT) of every transaction.
> 
> Any suggestions/comments are welcome.
> 
> Thanks & Regards,
> Girish.
> 
> 
>