Re: [RFC][PATCH] Set JBD2_FEATURE_INCOMPAT_64BIT on filesystems larger than 32-bit blocks (take 2).

[Dave Kleikamp <shaggy@linux.vnet.ibm.com>]

On Tue, 2007-06-05 at 06:41 -0500, Jose R. Santos wrote:
> On Mon, 04 Jun 2007 16:01:45 -0700
> Mingming Cao <cmm@us.ibm.com> wrote:
> 
> > On Mon, 2007-06-04 at 11:57 -0600, Andreas Dilger wrote:
> > > On Jun 04, 2007  11:32 -0500, Jose R. Santos wrote:
> > > > Set the journals JBD2_FEATURE_INCOMPAT_64BIT on devices with more
> > > > than 32bit block sizes during mount time.  This ensure proper record
> > > > lenth when writing to the journal.
> > > > 
> > > > Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
> > > > ---
> > > >  fs/ext4/super.c |   11 +++++++++++
> > > >  1 file changed, 11 insertions(+)
> > > > 
> > > > Index: linux-2.6.22-rc3/fs/ext4/super.c
> > > > ===================================================================
> > > > --- linux-2.6.22-rc3.orig/fs/ext4/super.c	2007-06-04 11:01:20.028360650 -0500
> > > > +++ linux-2.6.22-rc3/fs/ext4/super.c	2007-06-04 11:05:11.389126418 -0500
> > > > @@ -1824,6 +1824,17 @@ static int ext4_fill_super (struct super
> > > >  		goto failed_mount3;
> > > >  	}
> > > >  
> > > > +        /*
> > > > +	 * Make sure to set JBD2_FEATURE_INCOMPAT_64BIT on filesystems
> > > > +	 * with more that 32-bit block counts
> > > > +	 */
> > > > +	if(es->s_blocks_count_hi &&
> > 
> > This need to be le32_to_cpu(es->s_blocks_count_hi)
> 
> I'm curious,
> 
> Why do we need to do an endian conversion to check for a non-zero value
> in s_blocks_count_hi?  Seems unnecessary here.

Jose is right.  The endian conversion is unnecessary.

Shaggy
-- 
David Kleikamp
IBM Linux Technology Center