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From: Felipe Monteiro de Carvalho <felipemonteiro.carvalho@gmail.com>
To: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-ext4@vger.kernel.org
Subject: Re: Beginner questions about ext4
Date: Mon, 15 Jul 2013 18:09:03 +0200	[thread overview]
Message-ID: <CACyNnZPnzEbcFj69+fGjm1rkLay51WTXFMqr25AOzY3vtvegpw@mail.gmail.com> (raw)
In-Reply-To: <20130715134357.GA26359@thunk.org>

Hello,

Thanks. Now I think that I am getting closer to something more concrete.

My superblock says:

superblock^.s_blocks_per_group = 32768
superblock^.s_inodes_per_group = 8080
superblock^.s_log_block_size = 2 -> so each block has 4k bytes

And when reading the root "/"  I obtain the following information for
the directory /bin/ : inode=8081

So I calculate that it should have:
groupnr=1 (because it is above 8080 inodes per group)
offset for groupnr 1 --> 4k * 32768 = 0x8000000

But I have utilized a hex editor (oh boy, it was hard to find one that
would read files over 4GB....) And the directory listing of /bin/ is
located in aprox. near 0x21B0000

As if each block group would have a size of 0x2000000 .... but this
size would be valid I would expect if
superblock^.s_blocks_per_group=8192 ...

Any idea what I missed here that the calculations went wrong?

thanks,
-- 
Felipe Monteiro de Carvalho

  reply	other threads:[~2013-07-15 16:09 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-12 12:20 Beginner questions about ext4 Felipe Monteiro de Carvalho
2013-06-23  6:29 ` Felipe Monteiro de Carvalho
2013-06-23 11:59   ` Theodore Ts'o
2013-07-01 15:23     ` Felipe Monteiro de Carvalho
2013-07-01 16:55       ` Theodore Ts'o
2013-07-10 16:13         ` Felipe Monteiro de Carvalho
2013-07-10 17:24           ` Theodore Ts'o
2013-07-11  7:37             ` Felipe Monteiro de Carvalho
2013-07-11 15:23               ` Theodore Ts'o
2013-07-15 10:20     ` Felipe Monteiro de Carvalho
2013-07-15 13:43       ` Theodore Ts'o
2013-07-15 16:09         ` Felipe Monteiro de Carvalho [this message]
2013-07-15 16:37           ` Theodore Ts'o
2013-07-15 17:55             ` Felipe Monteiro de Carvalho
2013-07-15 18:10               ` Theodore Ts'o
2013-07-15 18:18                 ` Felipe Monteiro de Carvalho
2013-07-15 18:59                   ` Theodore Ts'o
2013-07-16  6:14                     ` Felipe Monteiro de Carvalho

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