Subject: Re: vnd, VOP_ and encrypted fs.
To: Artur Grabowski <art@blahonga.org>
From: Jason R Thorpe <thorpej@wasabisystems.com>
List: tech-kern
Date: 10/31/2001 07:58:40
On Wed, Oct 31, 2001 at 11:08:33AM +0100, Artur Grabowski wrote:
> Jorgen Lundman <lundman@lundman.net> writes:
>
> > To which they have an "if vndsimple(bp->b_dec)) { " to test whether or
> > not it should use the new method. (Which appears to be an &0x80 test).
>
> The man-page usually helps.
>
> "There are two variants, the traditional vnd that
> bypasses the buffercache and thus is suitable for swap on files, but not
> for building disk-images, and the svnd ("safe" vnd ) variant that goes
> through the buffercache, thereby maintaining cache-coherency after the
> block-device is closed which makes it suitable for creating disk images.
> The latter is not good for swapping on, though."
There is no need for this change in NetBSD, of course. NetBSD's vnd fixed
the two-layer coherency problem a different way quite some time ago.
--
-- Jason R. Thorpe <thorpej@wasabisystems.com>