vhost-net: tell tap backend about the vnet endianness

The default behaviour for TAP/MACVTAP is to consider vnet as native endian.

This patch handles the cases when this is not true:
- virtio 1.0: always little-endian
- legacy cross-endian

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Greg Kurz 2015-06-17 15:23:49 +02:00 committed by Michael S. Tsirkin
parent 4ee9b43be9
commit 5be7d9f1b1

View File

@ -38,6 +38,7 @@
#include "standard-headers/linux/virtio_ring.h"
#include "hw/virtio/vhost.h"
#include "hw/virtio/virtio-bus.h"
#include "hw/virtio/virtio-access.h"
struct vhost_net {
struct vhost_dev dev;
@ -197,6 +198,27 @@ static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index)
net->dev.vq_index = vq_index;
}
static int vhost_net_set_vnet_endian(VirtIODevice *dev, NetClientState *peer,
bool set)
{
int r = 0;
if (virtio_has_feature(dev, VIRTIO_F_VERSION_1) ||
(virtio_legacy_is_cross_endian(dev) && !virtio_is_big_endian(dev))) {
r = qemu_set_vnet_le(peer, set);
if (r) {
error_report("backend does not support LE vnet headers");
}
} else if (virtio_legacy_is_cross_endian(dev)) {
r = qemu_set_vnet_be(peer, set);
if (r) {
error_report("backend does not support BE vnet headers");
}
}
return r;
}
static int vhost_net_start_one(struct vhost_net *net,
VirtIODevice *dev)
{
@ -314,6 +336,11 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
goto err;
}
r = vhost_net_set_vnet_endian(dev, ncs[0].peer, true);
if (r < 0) {
goto err;
}
for (i = 0; i < total_queues; i++) {
vhost_net_set_vq_index(get_vhost_net(ncs[i].peer), i * 2);
}
@ -321,7 +348,7 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true);
if (r < 0) {
error_report("Error binding guest notifier: %d", -r);
goto err;
goto err_endian;
}
for (i = 0; i < total_queues; i++) {
@ -343,6 +370,8 @@ err_start:
fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e);
fflush(stderr);
}
err_endian:
vhost_net_set_vnet_endian(dev, ncs[0].peer, false);
err:
return r;
}
@ -365,6 +394,8 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
fflush(stderr);
}
assert(r >= 0);
assert(vhost_net_set_vnet_endian(dev, ncs[0].peer, false) >= 0);
}
void vhost_net_cleanup(struct vhost_net *net)