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Date: Tue, 24 Jul 2007 02:50:56 -0600
From: Andreas Dilger <adilger@clusterfs.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Fengguang Wu <fengguang.wu@gmail.com>,
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Subject: Re: [PATCH 0/3] readahead drop behind and size adjustment
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On Jul 23, 2007  18:17 -0700, Andrew Morton wrote:
> hm, yes, there is a risk that the code was accidentally correct.  Or the
> code has only ever dealt with power-of-2 inputs, in which case it happens
> to work either way.
> 
> David(s) and ext4-people: could we please have a close review of these
> changes?
> > @@ -1706,8 +1704,8 @@ static int ext4_fill_super (struct super
> > -	sbi->s_addr_per_block_bits = log2(EXT4_ADDR_PER_BLOCK(sb));
> > -	sbi->s_desc_per_block_bits = log2(EXT4_DESC_PER_BLOCK(sb));
> > +	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
> > +	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));

For the ext[234] code there has only ever been power-of-two values for
ADDR_PER_BLOCK() and DESC_PER_BLOCK().

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.