Re: [ext2resize] Patches for ext2resize?

[Takashi S. <sh...@tn...>]

Hi,

> 
>> I found a bug in my patch which you applied to CVS.
> 
> If I understand you correctly, you suggest this change.  How can I
> test if the change work or not?  How can I reproduce the error it is
> fixing?

This change works only when ext2prepare adds reserved group 
descriptor blocks.

This is reproduced by the following procedure.

#mke2fs /dev/XXX -j -b 16384 3294967295
#ext2prepare /dev/XXX 4294967295

In case 4KB blocksize, this problem doesn't occur because
fs->sb.s_blocks_per_group is set to 32768, which is a multiple of
1024(fs->u32perblock), and both the following two cases give
the same result.

> -               if(((block - gdb_offset)%fs->u32perblock) != i)
> +               if(((block - gdb_offset)%fs->sb.s_blocks_per_group) != i)

While in case 16KB blocksize,  fs->sb.s_blocks_per_group seems
to be set to 65528, which is not a multiple of 4096(fs->u32perblock),
so this problem occurs.

> Index: src/ext2.c
> ===================================================================
> RCS file: /cvsroot/ext2resize/ext2resize/src/ext2.c,v
> retrieving revision 1.35
> diff -u -3 -p -r1.35 ext2.c
> --- src/ext2.c  11 Jun 2006 08:30:07 -0000      1.35
> +++ src/ext2.c  21 Jun 2006 13:42:23 -0000
> @@ -382,7 +382,7 @@ int ext2_block_iterate(struct ext2_fs *f
>                        ext2_brelse(bh, 0);
>                        return 1;
>                }
> -               if(((block - gdb_offset)%fs->u32perblock) != i)
> +               if(((block - gdb_offset)%fs->sb.s_blocks_per_group) != i)
>                        continue;
> 
>                bh2 = ext2_bread(fs, udata[i]);
> 
> Friendly,
> -- 
> Petter Reinholdtsen

Cheers, sho