On 09/21/2018 04:33 AM, Jason Wang wrote:
On 2018年09月21日 04:39, Maxime Coquelin wrote:
Hi Wei, Jason,
On 06/19/2018 09:53 AM, Wei Xu wrote:
On Wed, Jun 06, 2018 at 11:48:19AM +0800, Jason Wang wrote:
On 2018年06月06日 03:08, w...@redhat.com wrote:
From: Wei Xu <w...@redhat.com>
last_avail, avail_wrap_count, used_idx and used_wrap_count are
needed to support vhost-net backend, all these are either 16 or
bool variables, since state.num is 64bit wide, so here it is
possible to put them to the 'num' without introducing a new case
while handling ioctl.
Unload/Reload test has been done successfully with a patch in vhost
kernel.
You need a patch to enable vhost.
And I think you can only do it for vhost-kenrel now since vhost-user
protocol needs some extension I believe.
OK.
Signed-off-by: Wei Xu <w...@redhat.com>
---
hw/virtio/virtio.c | 42 ++++++++++++++++++++++++++++++++++--------
1 file changed, 34 insertions(+), 8 deletions(-)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 4543974..153f6d7 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -2862,33 +2862,59 @@ hwaddr
virtio_queue_get_used_size(VirtIODevice *vdev, int n)
}
}
-uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n)
+uint64_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n)
{
- return vdev->vq[n].last_avail_idx;
+ uint64_t num;
+
+ num = vdev->vq[n].last_avail_idx;
+ if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) {
+ num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 16;
+ num |= ((uint64_t)vdev->vq[n].used_idx) << 32;
+ num |= ((uint64_t)vdev->vq[n].used_wrap_counter) << 48;
So s.num is 32bit, I don't think this can even work.
I mistakenly checked out s.num is 64bit, will add a new case in next
version.
Wouldn't be enough to just get/set avail_wrap_counter?
Something like this so that it fits into 32 bits:
if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) {
num |= ((uint64_t)vdev->vq[n].avail_wrap_counter) << 31;
}
Regards,
Maxime
Yes, actually, that's what I did for vhost kernel
(https://github.com/jasowang/net/blob/packed-host/drivers/vhost/vhost.c#L1418)
Oh yes, I forgot on what I based my implementation on.
Wei, Michael, do you agree with this? I will need to merge the Vhost
patch in DPDK in the coming two weeks.
Regards,
Maxime
Thanks
