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Message-ID: <ef242d300710210240y5a5cc412vb1a8606d02bd5108@mail.gmail.com>
Date: Sun, 21 Oct 2007 17:40:55 +0800
From: "Nai XIA" <nelson.xia@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: Re: The meaning of first_logical_block in do_mpage_readpage
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sorry, I think I've found the point.
first_logical_block is passed out in a "for" loop in "mpage_readpages"
and passed again to the next "do_mpage_readpage".

Sorry for the haste asking.


On 10/21/07, Nai XIA <nelson.xia@gmail.com> wrote:
> hi, it may be a stupid question, but I am not quite clear about what
> "first_logical_block" is used for as one of parameters of
> "do_mpage_readpage".
>
> I searched all the source code and I found that "first_logical_block"
> always equals zero when passed to "do_mpage_readpage" and is  used
> only in scope of "do_mpage_readpage".
>
> This makes me wonder about:
> 1. when should "first_logical_block" passed as non-zero values ?
> 2. why "first_logical_block" is one of args of "do_mpage_readpage"
> instead of being a local variable of it ? ( it seems that no one uses
> "first_logical_block" outside  "do_mpage_readpage")
>
> Anyone can help me out .
> Thanks in advance!
>