Subject: Re: Disk IO / UVM and Crypt FS..
To: enami tsugutomo <enami@but-b.or.jp>
From: Jorgen Lundman <lundman@lundman.net>
List: tech-kern
Date: 05/08/2002 15:46:32
enami tsugutomo wrote:
>>Is there a solution for me? Would I have to produce a new "actual"
>>buffer, which will be encrypted and put to disk and then dropped.
>
>
> I guess so, since page cache may be shared among others. You need to
> allocate new buffer, but you don't need to decrypt it.
That does feel like the "proper way". Not too sure how to make a copy of
the buffer, but that's good excertise. Would be tempting to only do it
if I can detect a page is read-only, but I suppose it wouldn't be any
more efficient not to copy, since I still would need to decrypt, and
that generally is much heavier, computationally. (Ignoring the
concurrancy issue as well!)
Cheers for the insight,
Lundy
--
Jorgen "Lord" Lundman <lundman@lundman.net>
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