Subject: Re: Disk IO / UVM and Crypt FS..
To: enami tsugutomo <>
From: Jorgen Lundman <>
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,


Jorgen "Lord" Lundman <>
Technology Manager, Unix Administrator
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