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Date: Fri, 10 Apr 2015 17:14:34 +0200
From: Greg Kurz <gkurz@linux.vnet.ibm.com>
Message-ID: <20150410171434.20f0b91f@bahia.local>
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Subject: Re: [Qemu-devel] [vhost-net] handle_tx: extract data from vq when
 !zcopy_used
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To: Catalin Vasile <catalinvasile92@gmail.com>
Cc: qemu-devel@nongnu.org

On Fri, 10 Apr 2015 15:58:33 +0300
Catalin Vasile <catalinvasile92@gmail.com> wrote:

> I'm really confused.
> Where does vhost-net (handle_tx) actually extract data from vq when zero
> copy is not used?
> I just see it popping a vq element, but not actually copying anything from
> there.

vhost-net just passes the pointers to the socket, whether zero copy is used
or not:

err = sock->ops->sendmsg(NULL, sock, &msg, len);

BTW, I think virtualization@lists.linux-foundation.org would have been more
appropriate since this isn't a about QEMU.

Cheers.

--
Greg