From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: More virtio users
Date: Tue, 12 Jun 2007 17:52:27 +1000
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Cc: kvm-devel <kvm-devel@lists.sourceforge.net>, Tejun Heo <htejun@gmail.com>,
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To: Jens Axboe <jens.axboe@oracle.com>
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On Tue, 2007-06-12 at 08:24 +0200, Jens Axboe wrote:
> On Tue, Jun 12 2007, Rusty Russell wrote:
> > On Mon, 2007-06-11 at 09:33 +0200, Jens Axboe wrote:
> > > The other main request type is blk_pc_request(). In the data setup it's
> > > indentical to blk_fs_request(), there's a bio chain off ->bio. It's a
> > > byte granularity entity though, so you should check ->data_len for the
> > > size of it. ->cmd[] holds a SCSI cdb, which is the command you are
> > > supposed to handle.
> > 
> > SCSI?  I'm even more lost now.
> > 
> > Q: So what *are* the commands?
> 
> They are SCSI commands!
> 
> > Q: Who puts them in my queue?
> 
> If you want to support SG_IO for instance, you'd have to deal with SCSI
> commands.

I do not.  If someone wants to implement a SCSI layer over virtio, I
think that's wonderful.  Fortunately, that's not the problem I'm trying
to solve.

> -o barrier=1 for ext3, it doesn't use barriers by default.

That's, um, a little disturbing.

But, it works.  Thanks!
Rusty.