From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44094) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UwHLt-0000GY-Nr for qemu-devel@nongnu.org; Mon, 08 Jul 2013 15:44:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UwHLs-0007c5-Kd for qemu-devel@nongnu.org; Mon, 08 Jul 2013 15:44:01 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:36365) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UwHLs-0007c1-E8 for qemu-devel@nongnu.org; Mon, 08 Jul 2013 15:44:00 -0400 Received: from /spool/local by e33.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 8 Jul 2013 19:43:52 -0000 Received: from d01relay01.pok.ibm.com (d01relay01.pok.ibm.com [9.56.227.233]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 5F3F41FF0024 for ; Mon, 8 Jul 2013 13:38:32 -0600 (MDT) Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay01.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r68JdVKv244112 for ; Mon, 8 Jul 2013 15:39:32 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r68JdVtL001035 for ; Mon, 8 Jul 2013 16:39:31 -0300 From: Anthony Liguori In-Reply-To: <1372338255-3934-4-git-send-email-peter.maydell@linaro.org> References: <1372338255-3934-1-git-send-email-peter.maydell@linaro.org> <1372338255-3934-4-git-send-email-peter.maydell@linaro.org> Date: Mon, 08 Jul 2013 14:39:27 -0500 Message-ID: <87txk4c040.fsf@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Subject: Re: [Qemu-devel] [PATCH 3/8] virtio: Add support for guest setting of queue size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell , qemu-devel@nongnu.org Cc: KONRAD Frederic , David Gibson , kvmarm@lists.cs.columbia.edu, Alexander Graf , patches@linaro.org Peter Maydell writes: > The MMIO virtio transport spec allows the guest to tell the host how > large the queue size is. Add virtio_queue_set_num() function which > implements this in the QEMU common virtio support code. > > Signed-off-by: Peter Maydell > --- > hw/virtio/virtio.c | 6 ++++++ > include/hw/virtio/virtio.h | 1 + > 2 files changed, 7 insertions(+) > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 8176c14..8805b8a 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -667,6 +667,12 @@ hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n) > return vdev->vq[n].pa; > } > > +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num) > +{ > + vdev->vq[n].vring.num = num; > + virtqueue_init(&vdev->vq[n]); I think some level of checking is probably needed on num since we do a tremendous amount of math on it. I doubt it's exploitable since it's always treated as a PA, but better to be safe than sorry. Regards, Anthony Liguori > +} > + > int virtio_queue_get_num(VirtIODevice *vdev, int n) > { > return vdev->vq[n].vring.num; > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index a6c5c53..95c4772 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -198,6 +198,7 @@ void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data); > void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data); > void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr); > hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n); > +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num); > int virtio_queue_get_num(VirtIODevice *vdev, int n); > void virtio_queue_notify(VirtIODevice *vdev, int n); > uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); > -- > 1.7.9.5