From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: RAID4 and RAID5 Code
Date: Fri, 15 May 2009 09:08:36 -0700
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To: SandeepKsinha <sandeepksinha@gmail.com>
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SandeepKsinha wrote:
> Hi all,
> 
> Looks like we have the same code for RAID 4 and RAID 5, I could see
> the same make_request for both.
> 
> Can someone point me in the code, where exactly we differentiate
> between these two. i.e updating checksum block, etc.
> 

RAID 4 is really nothing but a block layout algorithm for RAID 5 (which
has four more block layout algorithms.)  RAID 6 contains all five under
one "level".

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.