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Subject: A question on block_prepare_write()
From: Namhyung Kim <namhyung@gmail.com>
To: linux-fsdevel <linux-fsdevel@vger.kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>
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Date: Sat, 23 Oct 2010 22:44:42 +0900
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Hello,

I see block_prepare_write() has local variable wait[2] to keep track of
buffer_heads which are not up-to-date. But I'm wondering how it could be
guaranteed there will be no more than 2 such buffer_heads? Is there any
restriction on the usage of the function? Using MAX_BUF_PER_PAGE instead
of the magic number 2 is just useless? I couldn't find any comments or
documentation on this.

Any of your comments would be greatly appreciated. TIA. :-)

-- 
Regards,
Namhyung Kim